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Sample records for ddt metabolite 3-methylsulfonyl-dde

  1. Biphasic hormonal responses to the adrenocorticolytic DDT metabolite 3-methylsulfonyl-DDE in human cells

    SciTech Connect

    Asp, Vendela; Ulleras, Erik; Lindstroem, Veronica; Bergstroem, Ulrika; Oskarsson, Agneta; Brandt, Ingvar

    2010-02-01

    The DDT metabolite 3-methylsulfonyl-DDE (3-MeSO{sub 2}-DDE) has been proposed as a lead compound for an improved adrenocortical carcinoma (ACC) treatment. ACC is a rare malignant disorder with poor prognosis, and the current pharmacological therapy o,p'-DDD (mitotane) has limited efficacy and causes severe adverse effects. 3-MeSO{sub 2}-DDE is bioactivated by cytochrome P450 (CYP) 11B1 in mice and causes formation of irreversibly bound protein adducts, reduced glucocorticoid secretion, and cell death in the adrenal cortex of several animal species. The present study was carried out to assess similarities and differences between mice and humans concerning the adrenocorticolytic effects of 3-MeSO{sub 2}-DDE. The results support previous indications that humans are sensitive to the adrenocorticolytic actions of 3-MeSO{sub 2}-DDE by demonstrating protein adduct formation and cytotoxicity in the human adrenocortical cell line H295R. However, neither the irreversible binding nor the cytotoxicity of 3-MeSO{sub 2}-DDE in H295R cells was inhibited by the CYP11B1 inhibitor etomidate. We also report biphasic responses to 3-MeSO{sub 2}-DDE in cortisol and aldosterone secretion as well as in mRNA levels of the steroidogenic genes StAR, CYP11B1 and CYP11B2. Hormone levels and mRNA levels were increased at lower concentrations of 3-MeSO{sub 2}-DDE, while higher concentrations decreased hormone levels. These biphasic responses were not observed with o,p'-DDD or with the precursor DDT metabolite p,p'-DDE. Based on these results, 3-MeSO{sub 2}-DDE remains a viable lead compound for drug design, although the adrenocorticolytic effects of 3-MeSO{sub 2}-DDE in human cells seem more complex than in murine cells.

  2. Adrenocortical toxicity of 3-methylsulfonyl-DDE in mice. II. Mitochondrial changes following ecologically relevant doses

    SciTech Connect

    Joensson, C.J.R.; Rodriguez-Martinez, H.; Lund, B.O.; Bergman, A.; Brandt, I. )

    1991-02-01

    Transmission electron microscopy was used to characterize early ultrastructural lesions in the adrenal zona fasciculata of female C57BL mice given a single ip injection of the adrenocorticolytic DDT-metabolite 3-methylsulfonyl-DDE (MeSO2-DDE). Following 3 mg/kg, mitochondrial changes were observed 6 hr after dosing. At 12 and 24 hr the mitochondrial changes were conspicuous, with disorganization and disappearance of central cristae. At doses of 6, 12, and 25 mg/kg body wt initial (6 hr) mitochondrial vacuolization was observed, followed by disappearance of mitochondria (6-12 mg/kg) or cellular necrosis (25 mg/kg). The metabolic activation and binding of MeSO2-(14C)DDE in adrenal homogenates were determined in vitro. The irreversible binding of MeSO2-(14C)DDE to the mitochondria-containing adrenal S-9 pellet fraction was 50 times higher than that to the postmitochondrial S-12 supernatant fraction. The apparent Km was 2.1 microM and the apparent Vmax was 104 pmol/mg protein/30 min for the binding of MeSO2-(14C)DDE to S-0.3 supernatants. The irreversible protein binding was inhibited by metyrapone (Ki = 1 microM) and 11-deoxycorticosterone (Ki = 3 microM). In conclusion, the adrenal metabolic activation of MeSO2-DDE is suggested to be mediated by a mitochondrial cytochrome P450 form, presumably P450 (11 beta). A primary mitochondrial lesion develops and subsequently leads to degeneration and necrosis of the zona fasciculata.

  3. Label-free based quantitative proteomics analysis of primary neonatal porcine Leydig cells exposed to the persistent contaminant 3-methylsulfonyl-DDE.

    PubMed

    Kalayou, Shewit; Granum, Cesilie; Berntsen, Hanne Friis; Groseth, Per Kristian; Verhaegen, Steven; Connolly, Lisa; Brandt, Ingvar; de Souza, Gustavo Antonio; Ropstad, Erik

    2016-03-30

    Evidence that persistent environmental pollutants may target the male reproductive system is increasing. The male reproductive system is regulated by secretion of testosterone by testicular Leydig cells, and perturbation of Leydig cell function may have ultimate consequences. 3-Methylsulfonyl-DDE (3-MeSO2-DDE) is a potent adrenal toxicants formed from the persistent insecticide DDT. Although studies have revealed the endocrine disruptive effect of 3-MeSO2-DDE, the underlying mechanisms at cellular level in steroidogenic Leydig cells remains to be established. The current study addresses the effect of 3-MeSO2-DDE on viability, hormone production and proteome response of primary neonatal porcine Leydig cells. The AlamarBlue™ assay was used to evaluate cell viability. Solid phase radioimmunoassay was used to measure concentration of hormones produced by both unstimulated and Luteinizing hormone (LH)-stimulated Leydig cells following 48h exposure. Protein samples from Leydig cells exposed to a non-cytotoxic concentration of 3-MeSO2-DDE (10μM) were subjected to nano-LC-MS/MS and analyzed on a Q Exactive mass spectrometer and quantified using label-free quantitative algorithm. Gene Ontology (GO) and Ingenuity Pathway Analysis (IPA) were carried out for functional annotation and identification of protein interaction networks. 3-MeSO2-DDE regulated Leydig cell steroidogenesis differentially depending on cell culture condition. Whereas its effect on testosterone secretion at basal condition was stimulatory, the effect on LH-stimulated cells was inhibitory. From triplicate experiments, a total of 6804 proteins were identified in which the abundance of 86 proteins in unstimulated Leydig cells and 145 proteins in LH-stimulated Leydig cells was found to be significantly regulated in response to 3-MeSO2-DDE exposure. These proteins not only are the first reported in relation to 3-MeSO2-DDE exposure, but also display small number of proteins shared between culture conditions

  4. Persistence of DDT and its metabolites in a farm pond

    USGS Publications Warehouse

    Bridges, W.R.; Kallman, B.J.; Andrews, A.K.

    1963-01-01

    A farm pond near Morrison, Colorado, was treated with 0.02 p.p.m. of DDT in June 1961. The persistence and distribution of the insecticide in materials sampled from the aquatic environment were studied until November 1962. Detectable amounts of DDT were not found in the water after 3 weeks. Residues in the mud had declined within 8 weeks after the treatment to levels not significantly higher than pre-treatment levels, but a sample of vegetation still contained relatively high levels of residues. From this time until the second summer, sufficient vegetation was not present to provide a sample for chemical analysis. A new crop of vegetation sampled 1 year after the treatment contained residues approximating pre-treatment levels. Fish accumulated 3 to 4 p.p.m. of DDT and its metabolites within 1 month after the treatment. The residue levels slowly declined after this, but when the study was terminated, 2 to 3 p.p.m. of the metabolites DDD and DDE still remained in the fish. The highest residue levels measured in crayfish were about one-half of those found in fish. Some mortality of the more susceptible fish and invertebrates occurred as a result of the DDT treatment; however, severe adverse effects were not demonstrated.

  5. Persistence of DDT and metabolites in wildlife from Washington State orchards

    USGS Publications Warehouse

    Blus, L.J.; Henny, C.J.; Stafford, C.J.; Grove, R.A.

    1987-01-01

    Residues of the DDT group, particularly p,p'-DDT (DDT) were detected in high or unusual amounts in some wildlife samples collected in fruit orchards near Wenatchee, Washington from 1979 to 1983. Samples of birds contained p,p'-DDE (DDE) and DDT in ratios (DDE:DDT) as low as 2.6:1 in eggs and 1.9:1 in brains. An unexpectedly high number (about 50%) of some samples, such as fat of adult waterfowl, contained unusually low DDE:DDT ratios (1000 kg/ha over this period. Considerable wildlife mortality from DDT was documented during the period of intensive use, but only one DDT-related mortality was recorded during this study. The possible origin of the residues is discussed. Occurrence of DDT and its metabolites in resident wildlife and its food indicates continuing contamination that probably originates largely from past legal applications in the orchard system.

  6. DDT AND ITS METABOLITES IN BREAST MILK FROM THE MADEIRA RIVER BASIN IN THE AMAZON, BRAZIL

    PubMed Central

    Azeredo, Antonio; Torres, João P. M.; de Freitas Fonseca, Márlon; Britto, José Lailson; Bastos, Wanderley Rodrigues; Azevedo e Silva, Cláudio E.; Cavalcanti, Giselle; Meire, Rodrigo Ornellas; Sarcinelli, Paula N.; Claudio, Luz; Markowitz, Steven; Malm, Olaf

    2008-01-01

    Until the 1990’s the 1,1,1-trichloro-bis-2,2′-(4chlorophenyl) ethane (DDT) was sprayed in the walls of the house in the along the Madeira River basin, Brazilian Amazon, a region well known by its large number of malaria cases. In the 1910, the relate of Oswaldo Cruz about health conditions in Madeira River region describes the presence of malaria in rates ranging until 100% of infected people in some localities. Data available in the literature points to the DDT contamination in fishes captured in Madeira River region. Fish is the major source of dietary protein to this people. DDT tends to accumulate in lipid rich tissues being eliminated by different events, including lactation. Considering the importance of the breast milk to the children feeding, the associated risks of DDT exposure via breast milk intake to children must be assessed. This is the main objective of this work: to analyse the presence of the p,p′-DDT and its metabolites p,p′-DDE and p,p′-DDD in 69 human milk samples and to estimate the intake of DDT and its metabolite in terms of total DDT (total DDT = p,p′-DDE+ p,p′-DDD+ p,p′-DDT). All sample showed contamination with DDT and its metabolites ranging from 25.4 to 9361.9 ng of total DDT / g of lipid (median=369.6 ng of total DDT / g of lipid) and 8.7 % of the Estimated Daily Intake (EDI), in terms of total DDT, was higher than the Acceptable Daily Intake proposed by the WHO. Key words: DDT, breast milk, children, organochlorine pesticide, fish. PMID:18495200

  7. Comparison of DDT and its metabolites concentrations in cow milk from agricultural and industrial areas.

    PubMed

    Kuba, Jarosław; Tomza-Marciniak, Agnieszka; Pilarczyk, Bogumiła; Tarasewicz, Natalia; Pilarczyk, Renata; Ligocki, Marek

    2015-01-01

    The risk of pesticidal intoxication in humans is severe, especially because of the strongly negative impact on human health. The consequences of the exposure to these substances may include cancerogenesis or endocrine abnormalities resulting for example in decreased fertility. Therefore, the aim of our study was to evaluate the content of dichlorodiphenyltrichloroethane (DDT) and its metabolites in cow milk from two regions of Poland, varying by level of industrialization. Samples were collected from agricultural (n = 25) and industrial (n = 25) areas, and the concentrations of DDT and its metabolites were evaluated by gas chromatography. Residues of DDT were detected in all the milk samples tested, mostly in the samples from the agricultural area, where a total DDT median concentration reached 0.336 μg L(-1). In the milk samples from the industrial area, the median concentration was lower, at 0.131 μg L(-1). 4,4'-DDT was the main metabolite, constituting 83% of total DDT metabolites. Although none of the samples exceeded the level above which they should be considered dangerous, the results showed that the problem of DDT had not diminished and so should be constantly monitored. PMID:25421622

  8. Exposure of mother-child and postpartum woman-infant pairs to DDT and its metabolites in Tianjin, China.

    PubMed

    Wang, Yan-Rang; Zhang, Ming; Wang, Qian; Yang, De-Yi; Li, Chao-Lin; Liu, Jing; Li, Jian-Guo; Li, Hao; Yang, Xue-Ying

    2008-06-15

    1,1,1-trichloro-2,2'-bis(4-chlorophenyl)ethane (DDT) exhibits its long persistence in the environment, unusual bioaccumulation, effects on wildlife, and the possibility of long-term adverse effects on human health, especially reproductive toxicity. Despite the prohibition of most persistent organochlorine pesticides in China, the presence of organochlorine residue, including DDT, has been widely indicated in environmental substance. However, scarce information is available about accumulative levels of DDT in human tissues in China. To evaluate levels of DDT and its potential effects on women and children's health in a Chinese pesticide-exposed area, we recruited 50 pairs of mother-child and 50 postpartum women, and determined the levels of total DDT and its four main metabolites (p,p'-DDE, p,p'-DDT, p,p'-DDD, o,p'-DDT) in venous blood, breast milk and umbilical blood cord by gas chromatography. Accordingly, data on reproductive outcomes of mothers and postpartum women and healthy status of children and infants were gathered through a questionnaire and medical examinations. Furthermore, we also assayed the DDT levels of some environmental samples (soil, food, milk, et al.). The levels of DDT in children's blood were higher than that in the women's. As compared to breast milk, the umbilical blood cord and the ventral fat individually demonstrated a significantly lower and higher level of DDT in the postpartum women. DDT was lower in milk and crucian carp than in the soil near the chemical plant. p,p'-DDT and p,p'-DDE were the main metabolites of DDT. Our findings suggested the cumulative effect of DDT in human body in Tianjin, China. PMID:18387653

  9. Occurrences and fate of DDT principal isomers/metabolites, DDA, and o,p'-DDD enantiomers in fish, sediment and water at a DDT-impacted Superfund site.

    PubMed

    Garrison, A W; Cyterski, M; Roberts, K D; Burdette, D; Williamson, J; Avants, J K

    2014-11-01

    In the 1950s and 60s, discharges from a DDT manufacturing plant contaminated a tributary system of the Tennessee River near Huntsville, Alabama, USA. Regulatory action resulted in declaring the area a Superfund site which required remediation and extensive monitoring. Monitoring data collected from 1988, after remediation, through 2011 showed annual decreases approximating first-order decay in concentrations of total DDT and its six principal congeners (p,p'-DDT, o,p'-DDT, p,p'-DDD, o,p'-DDD, p,p'-DDE and o,p'-DDE) in filets from three species of fish. As of 2013, these concentrations met the regulatory requirements of 5 mg/kg or less total DDT for each fish tested. The enantiomer fractions (EF) of chiral o,p'-DDD in smallmouth buffalo and channel catfish were always below 0.5, indicating preferential decay of the (+)-enantiomer of this congener; this EF did not change significantly over 15 years. The often-neglected DDT metabolite p,p'-DDA was found at a concentration of about 20 μg/l in the ecosystem water. PMID:25150505

  10. DDT and its metabolites alter gene expression in human uterine cell lines through estrogen receptor-independent mechanisms.

    PubMed Central

    Frigo, Daniel E; Burow, Matthew E; Mitchell, Kamron A; Chiang, Tung-Chin; McLachlan, John A

    2002-01-01

    Endocrine-disrupting organochlorines, such as the pesticide dichlorodiphenyltrichloroethane (DDT), bind to and activate estrogen receptors (ERs), thereby eliciting estrogen-like effects. Although ERs function predominantly through activation of transcription via estrogen-responsive elements, both ERs, alpha and ss, can interact with various transcription factors such as activator protein-1 (AP-1). Additionally, estrogens may regulate early signaling events, suggesting that the biological effects of environmental estrogens may not be mediated through classic ER (alpha and ss) activity alone. We hypothesized that known environmental estrogens, such as DDT and its metabolites, activate AP-1-mediated gene transactivation through both ER-dependent and ER-independent means. Using two Ishikawa human endometrial adenocarcinoma cell line variants that we confirmed to be estrogen responsive [Ishikawa(+)] and estrogen unresponsive [Ishikawa(-)], we generated stably transfected AP-1 luciferase cell lines to identify the role of an estrogen-responsive mechanism in AP-1-mediated gene expression by various stimuli. Our results demonstrate that DDT and dichlorodiphenyldichloroethane (DDD) were the most potent activators of AP-1 activity; 2,2-bis(p-chlorophenyl) acetic acid failed to activate. Although stimulated in both Ishikawa(+) and Ishikawa(-) cells by DDT and its congeners, AP-1 activation was more pronounced in the estrogen-unresponsive Ishikawa(-) cells. In addition, DDT, DDD, and dichlorodiphenyldichloroethylene (DDE) could also stimulate AP-1 activity in the estrogen-unresponsive human embryonic kidney 293 cells using a different promoter context. Thus, our data demonstrate that DDT and its metabolites activate the AP-1 transcription factor independent of ER (alpha or ss) status. PMID:12460804

  11. Stimulation of anaerobic biodegradation of DDT and its metabolites in a muck soil: laboratory microcosm and mesocosm studies.

    PubMed

    Gohil, Hiral; Ogram, Andrew; Thomas, John

    2014-09-01

    The aim of this study was to evaluate the impact of selected electron donors and electron acceptors on the anaerobic biodegradation of DDT and its major metabolites in a muck soil with a long history of exposure to the pesticide. Loss of DDT was measured in anaerobic microcosms supplemented with H2, lactate, and acetate. The greatest loss of DDT (approximately 87 %) was observed in microcosms amended with lactate and no additional electron acceptor compared to the no additional electron donor or acceptor sets. An increase in measureable concentrations of DDx was observed in un-amended microcosms. In larger scale mesocosms, significant increases in dissolved organic carbon (DOC) corresponded with low redox potentials. Increases in DOC corresponded with sharp increases in measured concentrations of DDx, followed by a decrease in measured DDT concentrations in lactate-amended mesocosms. Our studies indicate that sorbed DDx is released upon anaerobic incubation, and that indigenous microorganisms capable of DDx degradation respond to lactate additions. Both the potential for release of sorbed DDx and the potential for biodegradation of DDx should be considered during remediation of DDx-contaminated organic soils at low redox potentials. PMID:24584703

  12. Presence of DDT metabolites in water, sediment and fish muscle tissue from Lake Prespa, Republic of Macedonia.

    PubMed

    Veljanoska-Sarafiloska, Elizabeta M; Jordanoski, Momčula; Stafilov, Trajče

    2013-01-01

    Organochlorine pesticides were determined in water and sediment samples collected from the littoral zone of Lake Prespa, as well as from its three main tributaries (the rivers Golema, Brajcinska and Kranska), during the period 2004 to 2006. In addition, muscle tissue samples of barbus fish (Barbus prespensis Karaman, 1928) collected from the littoral zone of Lake Prespa were also analysed. The obtained results give an overview of the contamination levels of these problematic compounds at their potential sources in the river mouths, in the potentially affected, species-rich littoral section of the lake and in the muscle tissue of one selected fish species, collected near the rivers' deltas. Special attention was paid to the presence of some DDT metabolites (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE); (1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (p,p'-DDD) and 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p'-DDT). The extraction of pesticides from water samples was done by liquid-liquid partition in dichloromethane. For the sediment and fish tissue we used solid-liquid extraction. The extracted residues were analyzed on a gas chromatograph equipped with an electron capture detector (GC-ECD). The results of the respective studies indicated the presence of DDT metabolic forms in the samples of the three analysed matrixes. The highest levels of presence for these pollutants were found in the muscle tissue of the fish samples. The total DDTs content in the analysed muscle tissue samples range from 11.67 to 13.58 μg kg⁻¹ of fresh tissue. The average total DDTs content for the sediment samples were within the range of 2.32 to 4.17 μg kg⁻¹ of dry sediment. Higher DDT metabolites content were found in the sediments collected from the rivers than in the samples from the littoral zone. The lowest average total concentrations of DDTs, on the other hand, were recorded in the water samples and ranged between 0.036 and 0.057 μg L⁻¹. The obtained results

  13. Differential effects of the organochlorine pesticide DDT and its metabolite p,p'-DDE on p-glycoprotein activity and expression

    SciTech Connect

    Shabbir, Arsalan; DiStasio, Susan; Zhao, Jingbo; Cardozo, Christopher P.; Wolff, Mary S.; Caplan, Avrom J. . E-mail: avrom.caplan@mssm.edu

    2005-03-01

    1,1-Bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT) is an organochlorine pesticide. Its metabolite, 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethene (p,p'-DDE) is a persistent environmental contaminant and both compounds accumulate in animals. Because multidrug resistance transporters, such as p-glycoprotein, function as a defense against xenobiotic exposure, we analyzed the ability of DDT and p,p'-DDE to act as efflux modulators. Using a competitive intact cell assay based on the efflux of the fluorescent dye rhodamine 123, we found that DDT, but not p,p'-DDE, stimulated dye retention. Subsequent studies using verapamil as competitor suggested that DDT is a weak p-glycoprotein inhibitor. Further studies addressed the ability of DDT and p,p'-DDE to induce MDR1, the gene encoding p-glycoprotein. In HepG2 cells, we found that both compounds induced MDR1 by twofold to threefold. Similar results were observed in mouse liver after a single dose of p,p'-DDE, although some gender-specific induction differences were noted. By contrast, p,p'-DDE failed to induce MDR1 in HeLa cells, indicating some cell-specific effects for induction. Further expression studies demonstrated increased levels of the endoplasmic reticulum molecular chaperone, Bip, in response to DDT, but not p,p'-DDE. These results suggest that DDT, but not p,p'-DDE, induces an endoplasmic reticulum stress response.

  14. The effect of DDT and its metabolite (DDE) on prostaglandin secretion from epithelial cells and on contractions of the smooth muscle of the bovine oviduct in vitro

    SciTech Connect

    Wrobel, Michal H.; Mlynarczuk, Jaroslaw; Kotwica, Jan

    2012-03-01

    The insecticide DDT and its metabolite (DDE), due to their lipolytic nature and resistance to biodegradation, are accumulated in the living tissues. In cows, DDT and DDE were found to affect prostaglandin (PG) secretion from the endometrium and contractions of the myometrium. In this study, the impact of both xenobiotics (0.1, 1, 10 or 100 ng/ml) on the function of epithelial cells and muscle strips of bovine oviducts from 1 to 5 day of the oestrous cycle was examined. Therefore the concentration of PGE2 and PGFM (a metabolite of PGF2α) in culture media, mRNA expression of genes involved in PGs synthesis in epithelial cells and the force and amplitude of strips contractions were measured after 2 and 24 or 48 h of incubation. Neither DDT nor DDE affected the viability of cells after 48 h (P > 0.05). Both DDT and DDE increased the concentrations of PGFM in culture medium and secretion of PGE2 after only 2 h of cell culture (P < 0.05). Similar effects were seen for the influence of DDE on amount of PGFM after 48 h, while DDT decreased secretion of PGE2 (P < 0.05). DDT after 2 h increased (P < 0.05) mRNA expression of PGF2α synthase (PGFS), while both xenobiotics decreased (P < 0.05) mRNA expression of cyclooxygenase-2 (COX-2) after 24 h. DTT also increased the force of isthmus contractions after 2 h, as did both xenobiotics after 48 h (P < 0.05). Moreover, after 2 and 48 h, DDE stimulated the amplitude of contractions of the isthmus as well as the ampulla, (P < 0.05). The effect of both compounds on oviduct contractions was diminished by indomethacin, which blocks PG synthesis. We conclude that oviductal secretion of prostaglandins is affected, by DDT and DDE. The influence of these xenobiotics on PGF2α and PGE2 secretion and ratio may be part of the mechanism by which both DDT and its metabolite disturb the contractions of oviductal muscle. -- Highlights: ► DDT and its metabolite – DDE are accumulated in the living tissues. ► The insecticides affected PGF2

  15. Assessing Bioavailability of DDT and Metabolites in Marine Sediments using Solid-Phase Microextraction with Performance Reference Compounds

    PubMed Central

    Bao, Lian-Jun; Jia, Fang; Crago, J.; Zeng, Eddy Y.; Schlenk, D.; Gan, Jay

    2014-01-01

    Solid-phase microextraction (SPME) has often been used to estimate the freely dissolved concentration (Cfree) of organic contaminants in sediments. A significant limitation in the application of SPME for Cfree measurement is the requirement for attaining equilibrium partition, which is often difficult for strongly hydrophobic compounds such as DDT. A method was developed using SPME with stable isotope-labeled analogues as performance reference compounds (PRCs) to measure Cfree of DDT and metabolites (DDTs) in marine sediments. Six 13C-labeled or deuterated PRCs were impregnated into polydimethylsiloxane (PDMS) fiber before use. Desorption of PRCs from PDMS fibers and absorption of DDTs from sediment were isotropic in a range of sediments evaluated ex situ under well-mixed conditions. When applied to a historically contaminated marine sediment from a Superfund site, the PRC-SPME method yielded Cfree values identical to those found by using a conventional equilibrium SPME approach (Eq-SPME), wherease the time for mixing was reduced from 9 d to only 9 h. The PRC-SPME method was further evaluated against bioaccumulation of DDTs by Neanthes arenaceodentata in the contaminated sediment with or without amendment of activated carbon or sand. Strong correlations were consistently found between the derived equilibrium concentrations on the fiber and lipid-normalized tissue residues for DDTs in the worms. Results from the present study clearly demonstrated the feasibility of coupling PRCs with SPME sampling to greatly shorten sampling time, thus affording much improved flexibility in the use of SPME for bioavailability evaluation. Environ Toxicol Chem 2013;32:1946–1953. PMID:23661411

  16. Occurences and Fate of DDT Principal Isomers/Metabolites, DDA, and o,p'-DDD Enantiomers in Fish, Sediment and Water at a DDT-Impacted Superfund Site

    EPA Science Inventory

    In the 1950s and 60s, discharges from a DDT manufacturing plant contaminated a tributary system of the Tennessee River near Huntsville, Alabama, USA. Regulatory action resulted in declaring the area a Superfund site which required remediation and extensive monitoring. Monitoring ...

  17. In vitro adrenal bioactivation and effects on steroid metabolism of DDT, PCBs and their metabolites in the gray seal (Halichoerus grypus)

    SciTech Connect

    Lund, B.O. . Dept. of Pharmacology and Toxicology)

    1994-06-01

    The irreversible binding of the DDT metabolites o,p[prime]-DDD [2-(2-chlorophenyl)-2(4-chlorophenyl)-1,1-dichloroethane] and MeSO[sub 2]-DDE [3-methylsulfonyl-2,2-bis(4-chlorophenyl)-1,1-dichloroethene], as well as their potential to inhibit mitochondrial steroid 11[beta]-hydroxylation in the gray seal adrenal gland, was studied. The adrenal bioactivated both o,p[prime]-DDD and MeSO[sub 2[minus

  18. DDT residues in starlings, 1974.

    PubMed

    Nickerson, P R; Barbehenn, K R

    1975-06-01

    In the preceding issue of this journal, the authors suggested that the mean level of DDT plus metabolites in starlings should drop below 0.1 ppm for the 1974 collection. They based their prediction on an analysis of the relationship between mean levels of DDT and its metabolites in starlings and estimates of domestic disappearance of DDT. The present brief summarizes initial findings from the 1974 starling collection. Authors indicate that their eariler estimates for disappearance of total DDT were optimistic: the geometric mean for 1974 was 0.282, a 36 percent reduction from the 1972 mean of 0.442. PMID:1181546

  19. Distribution and fate of HCH isomers and DDT metabolites in a tropical environment–case study Cameron Highlands–Malaysia

    PubMed Central

    2012-01-01

    Background The serious impact effects of persistent organic pollutants such as organochlorine pesticides, especially dichlorodiphenyltrichloroethane family (DDTs) and hexachlorocyclohexane isomers (HCHs) have been causing widespread concern, despite effective control on their manufacturing, agricultural and vector practices. In that, in addition to the previous global limitations on DDTs usage, α-HCH, β-HCH and lindane have also became an on-going topic of global relevance based on the latest Stockholm Convention list on 10th of May 2009. Concentrations of dichlorodiphenyltrichloroethane family (DDTs) and hexachlorocyclohexane isomers (HCHs) were determined by GC-ECD in Cameron Highlands, the main vegetables and flowers farming area in Malaysia as an agricultural tropical environment. A total of 112 surface water and sediment samples at eight points were collected along the main rivers in the area namely Telom and Bertam in the dry and wet seasons of 2011. Results Total concentration of HCH isomers ranged from not detected to 25.03 ng/L in the water (mean of 5.55 ±6.0 ng/L), while, it ranged from 0.002 to 59.17 ng/g (mean of 8.06±9.39 ng/g) in the sediment. Total concentration of DDT and its metabolites in the water samples varied from not detected to 8.0 ng/L (mean of 0.90±1.66 ng/g), whereas, it was in the range of 0.025 to 23.24 ng/g (mean of 2.55±4.0 ng/g) in the surface sediment samples. The ratio of HCHs and DDTs composition indicated an obvious historical usage and new inputs of these pesticides. Among alpha, beta, gamma and delta isomers of HCH, gamma was the most dominant component in the sediment and water as well. Some seasonal variations in the level of selected pesticides were noted. Conclusions The results illustrate distribution, behaviour and fate of HCHs, and DDTs have closely connected with topological and meteorological properties of the area beyond their chemical characterizations. The features of environmental circumstances exceed one or

  20. DDT contamination at Wheeler National Wildlife Refuge

    USGS Publications Warehouse

    O'Shea, T.J.; Fleming, W.J., III; Cromartie, E.

    1980-01-01

    Disposal of industrial waste resulted in massive DDT contamination atWheeler National Wildlife Refuge, Alabama. Nearly a decade after the cessation of DDT manufacturing at the facility responsible, concentrations of DDT residues in the local fauna are still high enough to suggest avian reproductive impairment and mortality. Populations of fish-eating birds are low, endangered species are being exposed, and muscle lipids of game birds contain up to 6900 parts of DDT (isomers and metabolites) per million.

  1. Analysis of DDT and its metabolites in soil and water samples obtained in the vicinity of a closed-down factory in Bangladesh using various extraction methods.

    PubMed

    Al Mahmud, M N U; Khalil, Farzana; Rahman, Md Musfiqur; Mamun, M I R; Shoeb, Mohammad; Abd El-Aty, A M; Park, Jong-Hyouk; Shin, Ho-Chul; Nahar, Nilufar; Shim, Jae-Han

    2015-12-01

    This study was conducted to monitor the spread of dichlorodiphenyltrichloroethane (DDT) and its metabolites (dichlorodiphenyldichloroethylene (DDE), dichlorodiphenyldichloroethane (DDD)) in soil and water to regions surrounding a closed DDT factory in Bangladesh. This fulfillment was accomplished using inter-method and inter-laboratory validation studies. DDTs (DDT and its metabolites) from soil samples were extracted using microwave-assisted extraction (MAE), supercritical fluid extraction (SFE), and solvent extraction (SE). Inter-laboratory calibration was assessed by SE, and all methods were validated by intra- and inter-day accuracy (expressed as recovery %) and precision (expressed as relative standard deviation (RSD)) in the same laboratory, at three fortified concentrations (n = 4). DDTs extracted from water samples by liquid-liquid partitioning and all samples were analyzed by gas chromatography (GC)-electron capture detector (ECD) and confirmed by GC/mass spectrometry (GC/MS). Linearities expressed as determination coefficients (R (2)) were ≥0.995 for matrix-matched calibrations. The recovery rate was in the range of 72-120 and 83-110%, with <15% RSD in soil and water, respectively. The limit of quantification (LOQ) was 0.0165 mg kg(-1) in soil and 0.132 μg L(-1) in water. Greater quantities of DDTs were extracted from soil using the MAE and SE techniques than with the SFE method. Higher amounts of DDTs were discovered in the southern (2.2-936 × 10(2) mg kg(-1)) or southwestern (86.3-2067 × 10(2) mg kg(-1)) direction from the factory than in the eastern direction (1.0-48.6 × 10(2) mg kg(-1)). An exception was the soil sample collected 50 ft (15.24 m) east (2904 × 10(2) mg kg(-1)) of the factory. The spread of DDTs in the water bodies (0.59-3.01 μg L(-1)) was approximately equal in all directions. We concluded that DDTs might have been dumped randomly around the warehouse after the closing of the factory. PMID:26559557

  2. Relevance of the bioavailable fraction of DDT and its metabolites in freshwater sediment toxicity: New insight into the mode of action of these chemicals on Dictyostelium discoideum.

    PubMed

    Sforzini, Susanna; Governa, Daniela; Boeri, Marta; Oliveri, Laura; Oldani, Alessandro; Vago, Fabio; Viarengo, Aldo; Borrelli, Raffaella

    2016-10-01

    In this work, the toxicity of lake sediments contaminated with DDT and its metabolites DDD and DDE (collectively, DDX) was evaluated with widely used toxicity tests (i.e., Vibrio fischeri, Daphnia magna, Pseudokirchneriella subcapitata, and Lumbriculus variegatus) and with the social amoeba Dictyostelium discoideum, a model organism that is also suitable for studying pollutant-induced alterations at the molecular and cellular levels. Although the DDX concentration in the sediments was high (732.5 ppb), the results suggested a minimal environmental risk; in fact, no evidence of harmful effects was found using the different bioassays or when we considered the results of more sensitive sublethal biomarkers in D. discoideum amoebae. In line with the biological results, the chemical data showed that the concentration of DDX in the pore water (in general a highly bioavailable phase) showed a minimal value (0.0071ppb). To confirm the importance of the bioavailability of the toxic chemicals in determining their biological effects and to investigate the mechanisms of DDX toxicity, we exposed D. discoideum amoebae to 732.5ppb DDX in water solution. DDX had no effect on cell viability; however, a strong reduction in amoebae replication rate was observed, which depended mainly on a reduction in endocytosis rate and on lysosomal and mitochondrial alterations. In the presence of a moderate and transient increase in reactive oxygen species, the glutathione level in DDX-exposed amoebae drastically decreased. These results highlight that studies of the bioavailability of pollutants in environmental matrices and their biological effects are essential for site-specific ecological risk assessment. Moreover, glutathione depletion in DDX-exposed organisms is a new finding that could open the possibility of developing new pesticide mixtures that are more effective against DDT-resistant malaria vectors. PMID:27340883

  3. DDT LEVELS IN MILK OF RURAL INDIGENT BLACKS

    EPA Science Inventory

    Human milk samples from low-income blacks residing in rural Mississippi and Arkansas and middle-class whites residing in metropolitan Nashville, Tennessee, were analyzed for DDT and its metabolites. The mean total DDT (DDE + DDT) whole milk concentration of 38 samples from indige...

  4. Toxicity and Carcinogenicity of Dichlorodiphenyltrichloroethane (DDT)

    PubMed Central

    Harada, Takanori; Takeda, Makio; Kojima, Sayuri; Tomiyama, Naruto

    2016-01-01

    Dichlorodiphenyltrichloroethane (DDT) is still used in certain areas of tropics and subtropics to control malaria and other insect-transmitted diseases. DDT and its metabolites have been extensively studied for their toxicity and carcinogenicity in animals and humans and shown to have an endocrine disrupting potential affecting reproductive system although the effects may vary among animal species in correlation with exposure levels. Epidemiologic studies revealed either positive or negative associations between exposure to DDT and tumor development, but there has been no clear evidence that DDT causes cancer in humans. In experimental animals, tumor induction by DDT has been shown in the liver, lung, and adrenals. The mechanisms of hepatic tumor development by DDT have been studied in rats and mice. DDT is known as a non-genotoxic hepatocarcinogen and has been shown to induce microsomal enzymes through activation of constitutive androstane receptor (CAR) and to inhibit gap junctional intercellular communication (GJIC) in the rodent liver. The results from our previously conducted 4-week and 2-year feeding studies of p,p′-DDT in F344 rats indicate that DDT may induce hepatocellular eosinophilic foci as a result of oxidative DNA damage and leads them to hepatic neoplasia in combination with its mitogenic activity and inhibitory effect on GJIC. Oxidative stress could be a key factor in hepatocarcinogenesis by DDT. PMID:26977256

  5. Dichlorodiphenyltrichloroethane (DDT): ubiquity, persistence, and risks.

    PubMed Central

    Turusov, Vladimir; Rakitsky, Valery; Tomatis, Lorenzo

    2002-01-01

    Due to uncontrolled use for several decades, dichlorodiphenyltrichloroethane (DDT), probably the best known and most useful insecticide in the world, has damaged wildlife and might have negative effects on human health. This review gives a brief history of the use of DDT in various countries and presents the results of epidemiologic and experimental studies of carcinogenesis. Even though its use has been prohibited in most countries for ecologic considerations, mainly because of its negative impact on wildlife, it is still used in some developing countries for essential public health purposes, and it is still produced for export in at least three countries. Due to its stability and its capacity to accumulate in adipose tissue, it is found in human tissues, and there is now not a single living organism on the planet that does not contain DDT. The possible contribution of DDT to increasing the risks for cancers at various sites and its possible role as an endocrine disruptor deserve further investigation. Although there is convincing experimental evidence for the carcinogenicity of DDT and of its main metabolites DDE and DDD, epidemiologic studies have provided contrasting or inconclusive, although prevailingly negative, results. The presence and persistence of DDT and its metabolites worldwide are still problems of great relevance to public health. Efficient pesticides that do not have the negative properties of DDT, together with the development of alternative methods to fight malaria, should be sought with the goal of completely banning DDT. PMID:11836138

  6. Perinatal exposure to the pesticide DDT impairs energy expenditure and metabolism in adult female mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dichlorodiphenyltrichloroethane (DDT) has been used extensively to control malaria, typhus, body lice and bubonic plague worldwide, until countries began restricting its use in the 1970s. Individuals exposed to elevated levels of DDT and its metabolite dichlorodiphenyldichloroethylene have an increa...

  7. Current internal exposure to pesticides in children and adolescents in Germany: blood plasma levels of pentachlorophenol (PCP), lindane (gamma-HCH), and dichloro(diphenyl)ethylene (DDE), a biostable metabolite of dichloro(diphenyl)trichloroethane (DDT).

    PubMed

    Heudorf, U; Angerer, J; Drexler, H

    2003-10-01

    Pesticides are widely used throughout the world in agriculture to protect crops, and in public health to control diseases transmitted by animal vectors or intermediate hosts. After the prohibition of organochlorines such as DDT internal exposure of the general population to the organochlorines has been reduced markedly. Herein, current internal exposure of children and adolescents in an urban area in Germany to PCP, lindane, and DDT/E is reported. One hundred and thirty children and adolescents took part in this voluntary investigation. All of them stated they had never used pesticides in their homes or for medical reasons. Blood plasma was analysed for pentachlorophenol (PCP), lindane (gamma-HCH), and dichloro(diphenyl)ethylene (DDE), a biostable metabolite of dichloro(diphenyl)trichloroethane (DDT), using gas chromatography/electron capture detection according to well established methods approved by the Deutsche Forschungsgemeinschaft. Median (and 95th percentiles) in the age groups < 6, 6- < 12, and 12- < 18 years of age were (microgram/l): DDE: 0.75 (4.45), 0.95 (5.04), 0.89 (8.77); DDT: < 0.1 (0.22), < 0.1 (0.25), < 0.1 (0.30); PCP: 2.48 (17.32), 2.69 (5.85), 2.08 (8.04); lindane: < 0.1 (0.12, < 0.1 (0.08), < 0.1 (0.09). High levels of internal exposure to DDT in two girls were probably obtained during a holiday stay in India; high PCP-levels in two other girls were caused by a leather jacket impregnated with PCP, and a holiday abroad, respectively. Current background levels of internal exposure to organochlorine insecticides in children and adolescents in Germany are quantified. Exposure to these substances in the general population is thought to occur mainly via residues in food, which are low in general, today. In special cases, however, individual exposures may be dominated by other sources, i.e. impregnated leather clothes. PMID:14626896

  8. Biodegradation of DDT by Stenotrophomonas sp. DDT-1: Characterization and genome functional analysis

    NASA Astrophysics Data System (ADS)

    Pan, Xiong; Lin, Dunli; Zheng, Yuan; Zhang, Qian; Yin, Yuanming; Cai, Lin; Fang, Hua; Yu, Yunlong

    2016-02-01

    A novel bacterium capable of utilizing 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) as the sole carbon and energy source was isolated from a contaminated soil which was identified as Stenotrophomonas sp. DDT-1 based on morphological characteristics, BIOLOG GN2 microplate profile, and 16S rDNA phylogeny. Genome sequencing and functional annotation of the isolate DDT-1 showed a 4,514,569 bp genome size, 66.92% GC content, 4,033 protein-coding genes, and 76 RNA genes including 8 rRNA genes. Totally, 2,807 protein-coding genes were assigned to Clusters of Orthologous Groups (COGs), and 1,601 protein-coding genes were mapped to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. The degradation half-lives of DDT increased with substrate concentration from 0.1 to 10.0 mg/l, whereas decreased with temperature from 15 °C to 35 °C. Neutral condition was the most favorable for DDT biodegradation. Based on genome annotation of DDT degradation genes and the metabolites detected by GC-MS, a mineralization pathway was proposed for DDT biodegradation in which it was orderly converted into DDE/DDD, DDMU, DDOH, and DDA via dechlorination, hydroxylation, and carboxylation, and ultimately mineralized to carbon dioxide. The results indicate that the isolate DDT-1 is a promising bacterial resource for the removal or detoxification of DDT residues in the environment.

  9. Effects of DDT, DDE, and PCBs on mitochondrial respiration. [Cockroaches

    SciTech Connect

    Khan, H.M.; Cutkomp, L.K.

    1982-11-01

    Data dealing with the action of DDT, its metabolite DDE and other related chlorinated compounds such as polychlorinated biphenyls (PCBs) are presented in this study. Results show that both DDT and DDE effectively reduce oxidative phosphorylation as determined from cockroach muscle mitochondria. DDT is more effective as was also determined for inhibition of oligomycin-sensitive Mg/sup 2 +/ATPase. The PCBs tested were uncouplers of oxidative phosphorylation. (JMT)

  10. Metabolite

    MedlinePlus

    A metabolite is any substance produced during metabolism (digestion or other bodily chemical processes). The term metabolite may also refer to the product that remains after a drug is broken down (metabolized) by the body.

  11. Steroid secretion following exposure of ovarian follicular cells to single congeners and defined mixture of polybrominateddibenzoethers (PBDEs), p,p'-DDT and its metabolite p,p'-DDE.

    PubMed

    Gregoraszczuk, Ewa Ł; Rak, Agnieszka; Kawalec, K; Ropstad, Erik

    2008-05-01

    The main objective of the present study was to describe in vitro effects of individual congeners of polybrominateddibenzoethers (PBDEs) (PBDE-47, 99, 100, 209), p,p'-dichlorodiphenyltrichloroethane (DDT) and p,p'-dichlorodiphenyldichloroethylene (DDE) present at the highest amount in real-life mixtures of POPs extracted from liver oil of burbot from Lake Mjøsa in Norway, and defined combinations of these compounds on steroidogenesis in porcine ovarian follicular cells. Co-culture of theca and granulosa cells (Gc) was exposed by individual congeners of PBDEs or mixture. Media samples were collected and used for cell viability and steroid determination, while cells were used for the measurement of caspase-3 activity. All investigated PBDEs congeners increased both testosterone (T) and estradiol (E2) secretion. We noted additive stimulatory action of BDE-47 and BDE-100 on both T and E2 secretion, and then inhibitory action on both of these hormones production when additionally BDE-99 and then BDE-209 were included in this mixture. The situation was different when DDT and DDE were added to the defined mixture. Stimulatory action on E2 secretion with parallel decrease of T secretion was noted. In conclusion, the data indicated: (1) stimulatory action of individual congeners of PBDEs on both E2 and T secretion by ovarian follicular cells points to stimulatory action on enzymes responsible for testosterone secretion; (2) the overall effect of a real-life mixture on the steroidogenic response in ovarian follicular cells could be dependent on the concentration of DDTs in the mixture; (3) the predicted effect of mixture, calculated based on a sum of independent action of individual congeners, was higher than that noted under the influence of defined mixture. PMID:18406082

  12. DDT remediation in contaminated soils: a review of recent studies.

    PubMed

    Sudharshan, Simi; Naidu, Ravi; Mallavarapu, Megharaj; Bolan, Nanthi

    2012-11-01

    Over the past few decades significant progress has been made in research on DDT degradation in the environment. This review is an update of some of the recent studies on the degradation and biodegradation pathways of DDT and its metabolites, particularly in soils. The latest reports on human toxicity shows that DDT intake is still occurring even in countries that banned its use decades ago. Ageing, sequestration and formation of toxic metabolites during the degradation processes pose environmental challenges and result in difficulties in bioremediation of DDT contaminated soils. Degradation enhancement strategies such as the addition of chelators, low molecular organic acids, co-solvent washing and the use of sodium and seaweeds as ameliorant have been studied to accelerate degradation. This review describes and discusses the recent challenges and degradation enhancement strategies for DDT degradation by potentially cost effective procedures based on bioremediation. PMID:22907383

  13. DDT: A Renaissance?

    ERIC Educational Resources Information Center

    Devlin, Robert M.

    1974-01-01

    A critical review is made of the literature linking DDT to harmful effects on animal life. Implications of a ban on the use of DDT are discussed and studies which have found relatively no harmful effect on non-insect life are cited. (JP)

  14. Biodegradation of DDT by Stenotrophomonas sp. DDT-1: Characterization and genome functional analysis

    PubMed Central

    Pan, Xiong; Lin, Dunli; Zheng, Yuan; Zhang, Qian; Yin, Yuanming; Cai, Lin; Fang, Hua; Yu, Yunlong

    2016-01-01

    A novel bacterium capable of utilizing 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) as the sole carbon and energy source was isolated from a contaminated soil which was identified as Stenotrophomonas sp. DDT-1 based on morphological characteristics, BIOLOG GN2 microplate profile, and 16S rDNA phylogeny. Genome sequencing and functional annotation of the isolate DDT-1 showed a 4,514,569 bp genome size, 66.92% GC content, 4,033 protein-coding genes, and 76 RNA genes including 8 rRNA genes. Totally, 2,807 protein-coding genes were assigned to Clusters of Orthologous Groups (COGs), and 1,601 protein-coding genes were mapped to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. The degradation half-lives of DDT increased with substrate concentration from 0.1 to 10.0 mg/l, whereas decreased with temperature from 15 °C to 35 °C. Neutral condition was the most favorable for DDT biodegradation. Based on genome annotation of DDT degradation genes and the metabolites detected by GC-MS, a mineralization pathway was proposed for DDT biodegradation in which it was orderly converted into DDE/DDD, DDMU, DDOH, and DDA via dechlorination, hydroxylation, and carboxylation, and ultimately mineralized to carbon dioxide. The results indicate that the isolate DDT-1 is a promising bacterial resource for the removal or detoxification of DDT residues in the environment. PMID:26888254

  15. Former DDT factory in Pakistan revisited for remediation: severe DDT concentrations in soils and plants from within the area.

    PubMed

    Younas, Asma; Hilber, Isabel; ur Rehman, Shafique; Khwaja, Mahmood; Bucheli, Thomas D

    2013-04-01

    A factory in Amman Garh near Nowshera, Khyber Pakhtunkhwa, Pakistan, produced dichlorodiphenyltrichloroethane (DDT) from 1963-1994. Consequently, earlier papers reported a soil contamination in the per mille range inside the former factory wall (88 m × 106 m) and up to 10 mg/kg of DDT in the surroundings in 2005-2007. The site within the factory wall was remonitored systematically in 2011 to complement the earlier data as a prerequisite for remediation, to put them in exposure context in a population developing area, and to suggest and evaluate the optimal remediation technique for the site. The contamination was drastically higher than the earlier published data, and the sum of DDT and its metabolitesDDT) was up to 65% in the soil. Grasses, shrubs, and trees growing in this severely contaminated site had 50-450 mg/kgdw of ΣDDT. Thus, people living nearby and husbandry as well as wild animals are heavily exposed to DDT. The semiarid climate favors wind drift and deposition of the pollutant. Additionally, DDT from products of herbivore animals feeding on the contaminated plants will enter the food web. To overcome the exposure and distribution of the DDT, the site within the factory wall was capped with 1.5 m of soil. This remediation technique represents the easiest and least expensive solution. Nevertheless, DDT can still evaporate or leach, and groundwater can rise in this flood-prone area and thereby become contaminated, especially because a binding layer is missing. PMID:23179221

  16. Genotoxic effects of p,p'-DDT (1,1,1-trichloro-2,2-bis-(chlorophenyl)ethane) and its metabolites in Zebra mussel (D. polymorpha) by SCGE assay and micronucleus test.

    PubMed

    Binelli, Andrea; Riva, Consuelo; Cogni, Daniele; Provini, Alfredo

    2008-06-01

    This is the first study to evaluate the potential genotoxicity of p,p'-DDT (1,1,1-trichloro-2,2-bis-(chlorophenyl)ethane) and its metabolites (p,p'-DDD and p,p'-DDE) in the sentinel mollusc Zebra mussel (Dreissena polymorpha). DNA damage was measured using the single cell gel electrophoresis (SCGE) assay and the micronucleus test (MN test), which represent two of the more sensitive biomarkers for genotoxicity evaluation. Three different concentrations (0.1, 2, and 10 mug/L) of each compound were administered in water for 168 hr, maintaining mussels at constant laboratory conditions and collecting several specimens every 48 hr for biochemical analyses. At the same time, the bioaccumulation process and the concentration/effect relationship were checked by GC-MS/MS analyses of mussel soft tissues. The SCGE assay results showed a clear and significant (P < 0.05) relationship between DNA injuries and tested doses for all the homologues throughout the 7-day exposure period. The final DNA damage due to p,p'-DDE was almost double that of the other two homologues that showed the same toxicity pattern. The micronucleus frequency analysis confirmed the genotoxicity potential of the three homologues and p,p'-DDE showed the highest irreversible DNA damage. The capability of Zebra mussels to biotransform the administered compound in the other homologues was demonstrated by multiple regression analyses carried out between the MN frequencies and the concentrations of the different homologues in the mussel soft tissues. A greater genotoxic potential of the p,p'-DDE with respect to the other two chemicals was revealed. PMID:18418866

  17. DDT concentration in fish from the Tapajós River in the Amazon region, Brazil.

    PubMed

    Mendes, Rosivaldo de Alcântara; Lopes, Anna Sylmara da Costa; de Souza, Larissa Costa; Lima, Marcelo de Oliveira; Santos, Lourivaldo da Silva

    2016-06-01

    DDT and metabolites were measured in six species of fish collected from the Tapajós River in the village of Barreiras, near the town of Itaituba in the Brazilian Amazon region. The selected fish were the most consumed and economically important to the local people. DDT was used frequently in this region for malaria control. Fish samples were analyzed after extraction by microwave-assisted extraction in hexane/acetone (8:2, v/v) by gas chromatography with electron capture detector. Residues of op'-DDT and pp'-DDT and metabolites were detected, including pp'-DDE, pp'-DDD, op'-DDT, and op'-DDE, in 98% of the samples, with a greater abundance of pp'-DDT. Total DDT levels were 7.1-249.5 ng g(-1) wet weight (w.w). The DDE/DDT ratio was low, indicating recent exposure to DDT. The study area that may be related to generated waste used in public health campaigns to combat mosquitos (Anopheles spp.), still present in the Amazon environment, that transmit malaria. DDT levels and metabolites found in fish species do not present risks to human health because they are below acceptable limits for consumption. PMID:27027561

  18. Nanoscale zerovalent iron-mediated degradation of DDT in soil.

    PubMed

    Han, Yuling; Shi, Nan; Wang, Huifang; Pan, Xiong; Fang, Hua; Yu, Yunlong

    2016-04-01

    Nanoscale zerovalent iron (nZVI)-mediated degradation of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) was investigated in a spiked soil under different conditions (iron sources, iron dosage, soil moisture, temperature, and soil types) and DDT-contaminated field. The degradation efficiency of p,p'-DDT by nZVI and nZVI coated with sodium oleate (SO-nZVI) was much higher than that by nZVI coated with polyimide (PI-nZVI). The rapid degradation of p,p'-DDT by nZVI only occurred in flooded soil. The degradation half-life of p,p'-DDT decreased significantly from 58.3 to 27.6 h with nZVI dosage from 0.5 to 2.0% and from 46.5 to 32.0 h with temperature from 15 to 35 °C. The degradation efficiency of p,p'-DDT by nZVI differed in Jinhua (JH), Jiaxing (JX), Xiaoshan (XS), Huajiachi (HJC), and Heilongjiang (HLJ) soils. A good correlation was found between the degradation half-life of p,p'-DDT and multiple soil properties. The probable nZVI-mediated degradation pathway of p,p'-DDT in soil was proposed as DDT → DDD/DDE → DDNS → DDOH based on the metabolites identified by GC-MS. The in situ degradation efficiency of residual DDTs in a contaminated field was profoundly enhanced by the addition of nZVI as compared to the control. It is concluded that nZVI might be an efficient agent for the remediation of DDT-contaminated soil under anaerobic environment. PMID:26611630

  19. Metabolic and mutagenicity studies on DDT and 15 derivatives. Detection of 1,1-bis(p-chlorophenyl)-2,2-dichloroethane and 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethyl acetate (kelthane acetate) as mutagens in Salmonella typhimurium and of 1,1-bis(p-chlorophenyl) ethylene oxide, a likely metabolite, as an alkylating agent.

    PubMed

    Planche, G; Croisy, A; Malaveille, C; Tomatis, L; Bartsch, H

    1979-05-01

    Using a novel in vitro technique, whereby microsomal enzymes were embedded in an agar layer to prolong their viability, 1,1-bis(p-chlorophenyl) ethylene(DDNU), a mammalian metabolite of 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (DDT), was converted by microsomal mono-oxygenases of mouse liver into 1,1-bis(p-chlorophenyl)-1,2-ethanediol (DDNU-diol). The putative epoxide intermediate, 1,1-bis(p-chlorophenyl)ethylene oxide (DDNU-oxide), a new compound, was synthesized; it showed weak alkylating activity with 4-(4-nitrobenzyl)pyridine but was not mutagenic in Salmonella typhimurium strains TA100 and TA98. DDT and 13 of its metabolites or putative synthetic derivatives, including 1,1-bis(p-chlorophenyl)-2,2-dichloroethylene (DDE), 1 1,1-bis(p-chlorophenyl)-2-chloroethylene (DDMU), 1,1-bis(p-chlorophenyl)-2-chloroethane (DDMS)-DDNU, 2,2-bis(p-chlorophenyl)ethanol (DDOH), bis(p-chlorophenyl)acetic acid (DDA) and 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethanol (Kethane), caused no mutagenic effects in S. typhimurium strains TA100 or TA98, either in the presence or absence of a mouse-liver microsomal fraction. 1,1-Bis(p-chlorophenyl)-2,2,2-trichloroethyl acetate (Kelthane acetate) was a direct-acting mutagen in strain TA100, whereas 1,1-bis(p-chlorophenyl)-2,2-dichloroethane (DDD) was mutagenic in TA98, only in the presence of a mouse-liver microsomal system. The results are discussed in relation to possible pathways whereby DDT is activated to mutagenic and/or carcinogenic metabolites. PMID:380827

  20. GONADAL DEVELOPMENT AND ENDOCRINE RESPONSES IN JAPANESE MEDAKA (ORYZIAS LATIPES) EXPOSED TO O,P'-DDT IN WATER OR THROUGH MATERNAL TRANSFER

    EPA Science Inventory

    Various isomers and metabolites of DDT disrupt endocrine systems and gonadal development in fish andxwildlife and o,p'-DDT has been shown to be a relatively potent estrogen agonist. In this study, we exposed Japanese medaka (Oryzias latipes) to o,p'-DDT using two exposure protoco...

  1. Influence of PCBs in water on uptake and elimination of DDT and DDE by lake trout

    USGS Publications Warehouse

    Hesselberg, Robert J.; Nicholson, Lawrence W.

    1981-01-01

    Researchers predicted that several hundred years would be required before DDT (1,1,1 trichloro-2,2-bis [P-chlorophyl] ethane) and its metabolites were likely to decrease to nondetectable levels in Lake Michigan. But following the ban on DDT in 1970, residues of total DDT in Lake Michigan lake trout (Salvelinus namaycush) declined rapidly from 10.5µg/g in 1970 to 5.7 µg/g in 1976. During this period, polychlorinated biphenyls (PCBs) were being detected in lake trout tissues at about 20 µg/g. It was hypothesized that the high level of PCBs being accumulated by fish may have influenced uptake and elimination of DDT and DDE (1,1-dichloro-2,2-bis [p-chlorophenyl] ethylene) by fish. To test this hyphophesis, fingeriing lake trout were exposed to various combinations of DDT, DDE (100 ng/liter), and PCBs (100 and 500 ng/liter) in water for 12 weeks. After DDT and DDe exposures were completed, exposure to PCBs was continued for an additional 16 weeks to measure any effect PCBs may have on the elimination of DDT and DDE by fish. Accumulation and elimination rates of DDT and DDE were compared. It was found that PCBs did not influence the accumulation or elimination rates of DDT or DDE in lake trout and therefore should not have had a major influence on the decline of DDT in lake trout.

  2. Short-tailed shrews: Toxicity and residue relationships of DDT, dieldrin, and endrin

    USGS Publications Warehouse

    Blus, L.J.

    1978-01-01

    Experiments involving dietary toxicity and residue relationships of DDT, dieldrin, and endrin were conducted with short-tailed shrews. Dietary concentrations of DDT dissolved in vegetable oils were usually more toxic than diets containing comparable amounts of powdered DDT. Younger shrews, particularly females, were more tolerant of powdered DDT than older animals; yet, there were no conspicuous age differences in toxicity of DDT dissolved in oils. In comparison to other mammals, short-tailed shrews are not unusually sensitive to DDT, dieldrin, or endrin on the basis of two-week feeding tests. The influence of age and sex on toxicity of DDT, endrin, and dieldrin was sometimes more important than body weight. Of those shrews of the same age and sex that were fed the same dietary dosage, heavier shrews were more tolerant than lighter individuals; and, heavier shrews tended to lose a greater percentage of body weight before death. There was a range of 15 to 105 DDT equivalents in brains of shrews dying on dietary dosages of DDT. Six shrews fed a high level of DDT seemed to have unusual metabolite capabilities and died with apparent lethal levels of DDD in their brains. Levels of dieldrin in brains of shrews that died on a dietary dosage of dieldrin ranged from 3.7 to 12.6 ppm. In the rates of gain and loss experiments where shrews were given diets containing 400 ppm DDT or 50 ppm dieldrin up to 17 days, high residues were noted in tissues of shrews after two weeks on a contaminated diet and a few died at that time. After shrews were placed on clean food, it was determined that >50% of the dieldrin residues in carcass and brain were lost in 50% of residues of DDT and metabolites in brains after 2 weeks on clean food; males lost nearly 50% of residues in carcasses after two weeks on clean food compared with a loss of only 11% in females.

  3. Systems Studies of DDT Transport

    ERIC Educational Resources Information Center

    Harrison, H. L.; And Others

    1970-01-01

    Major consequences of present and additional environmental quantities of DDT pesticide are predictable by mathematical models of transport, accumulation and concentration mechanisms in the Wisconsin regional ecosystem. High solubility and stability produce increased DDT concentrations at high organism trophic levels within world biosphere…

  4. Progress in Global Multicompartmental Modelling of DDT

    NASA Astrophysics Data System (ADS)

    Stemmler, I.; Lammel, G.

    2009-04-01

    Dichlorophenyltrichloroethane, DDT, and its major metabolite dichlorophenyldichloroethylene, DDE, are long-lived in the environment (persistent) and circulate since the 1950s. They accumulate along food chains, cause detrimental effects in marine and terrestrial wild life, and pose a hazard for human health. DDT was widely used as an insecticide in the past and is still in use in a number of tropical countries to combat vector borne diseases like malaria and typhus. It is a multicompartmental substance with only a small mass fraction residing in air. A global multicompartment chemistry transport model (MPI-MCTM; Semeena et al., 2006) is used to study the environmental distribution and fate of dichlorodiphenyltrichloroethane (DDT). For the first time a horizontally and vertically resolved global model was used to perform a long-term simulation of DDT and DDE. The model is based on general circulation models for the ocean (MPIOM; Marsland et al., 2003) and atmosphere (ECHAM5). In addition, an oceanic biogeochemistry model (HAMOCC5.1; Maier-Reimer et al., 2005 ) and a microphysical aerosol model (HAM; Stier et al., 2005 ) are included. Multicompartmental substances are cycling in atmosphere (3 phases), ocean (3 phases), top soil (3 phases), and vegetation surfaces. The model was run for 40 years forced with historical agricultural application data of 1950-1990. The model results show that the global environmental contamination started to decrease in air, soil and vegetation after the applications peaked in 1965-70. In some regions, however, the DDT mass had not yet reached a maximum in 1990 and was still accumulating mass until the end of the simulation. Modelled DDT and DDE concentrations in atmosphere, ocean and soil are evaluated by comparison with observational data. The evaluation of the model results indicate that degradation of DDE in air was underestimated. Also for DDT, the discrepancies between model results and observations are related to uncertainties of

  5. Cross-sectional study of a community with exceptional exposure to DDT

    SciTech Connect

    Kreiss, K.; Zack, M.M.; Kimbrough, R.D.; Needham, L.L.; Smrek, A.L.; Jones, B.T.

    1981-05-15

    The geometric mean level of total DDT in serum samples (76.2 ng/mL) from 499 persons living downstream from a defunct DDT-manufacturing plant was several times the national geometric mean (15.0 ng/mL). DDE isomers, metabolites of DDT, accounted for an average of 86.7% of total DDT. Total DDT levels increased with age, even when controlled for other independent variables also significantly associated with DDT: race, sex, fish consumption, years of residence, socioeconomic status, alcohol consumption, and serum triglyceride levels. Fish consumption, the second strongest determinant of DDT level, had one third the predictive power of age. Total DDT levels were not associated with specific illness or ill health. However, total DDT levels were positively associated with levels of serum cholesterol, triglyceride, and gamma-glutamyl transpeptidase. The finding that serum DDE levels increase with age suggests that no equilibrium in body burden has been reached or that pharmacokinetics or serum/adipose partition may vary with age.

  6. [Distribution and risk assessment of HCH and DDT in an abandoned pesticide factory site].

    PubMed

    Yu, Shi-Qing; Tang, Wei; Lu, Bin

    2011-09-01

    The distribution of HCH (alpha, beta, gamma, delta-HCH) and DDT (p,p'-DDT, o,p'-DDT, p,p'-DDD, p,p'-DDE) in an abandoned pesticide factory site was studied, and its risk assessment was carried out. 232 soil samples were collected from the field 72 points of 0-400 cm depth. Analysis showed that the residual content of HCH and DDT in soil were 2.6-80 130 microg/kg and non-detected-54 350 microg/kg respectively, and showed the characteristics of vertical migration. Both HCH and DDT degraded significantly in this site. The percentages of HCH isomers were alpha-HCH (56.9%) > beta-HCH (23. 3% ) > gamma-HCH (14.0%) > delta-HCH (5.8%), and the percentages of DDT and its metabolites were p,p'-DDT (42.1%) > p,p'-DDD (27.0%) > o,p'-DDT (18.0%) > p,p'-DDE (12.9%). There is no new input source of HCH and DDT at the site soil. The site as a residential land development will not be adverse on residents of non-cancer risk, but non-carcinogenic risk to children is significantly higher than that of adults. At this site, there exists the possibility of cancer risk, and the cancer risk to adults is higher than that to children. Remediation and treatment was necessary for the soil of the site. PMID:22165234

  7. SELECTIVE IN VITRO HORMONE ACTIVITY OF O,P'-DDT AND O,P'-METHOXYCHLOR OPTICAL ISOMERS

    EPA Science Inventory

    Components and metabolites of the pesticides DDT and Methoxychlor have been described as endocrine disrupting chemicals with estrogen and/or antiandrogen activity. We account the estrogen and antiandrogen activity of the individual enantiomers of o,p'-DDT and o,p'-Methoxychlor. O...

  8. The interactive biotic and abiotic processes of DDT transformation under dissimilatory iron-reducing conditions.

    PubMed

    Jin, Xin; Wang, Fang; Gu, Chenggang; Yang, Xinglun; Kengara, Fredrick O; Bian, Yongrong; Song, Yang; Jiang, Xin

    2015-11-01

    The objective of the study was to elucidate the biotic and abiotic processes under dissimilatory iron reducing conditions involved in reductive dechlorination and iron reduction. DDT transformation was investigated in cultures of Shewanella putrefaciens 200 with/without α-FeOOH. A modified first-order kinetics model was developed and described DDT transformation well. Both the α-FeOOH reduction rate and the dechlorination rate of DDT were positively correlated to the biomass. Addition of α-FeOOH enhanced reductive dechlorination of DDT by favoring the cell survival and generating Fe(II) which was absorbed on the surface of bacteria and iron oxide. 92% of the absorbed Fe(II) was Na-acetate (1M) extractable. However, α-FeOOH also played a negative role of competing for electrons as reflected by the dechlorination rate of DDT was inhibited when increasing the α-FeOOH from 1 g L(-1) to 5 g L(-1). DDT was measured to be toxic to S. putrefaciens 200. The metabolites DDD, DDE and DDMU were recalcitrant to S. putrefaciens 200. The results suggested that iron oxide was not the key factor to promote the dissipation of DDX (DDT and the metabolites), whereas the one-electron reduction potential (E1) of certain organochlorines is the main factor and that the E1 higher than the threshold of the reductive driving forces of DIRB probably ensures the occur of reductive dechlorination. PMID:26025430

  9. Action of defined mixtures of PCBs, p,p'-DDT and its metabolite p,p'-DDE, on co-culture of porcine theca and granulosa cells: steroid secretion, cell proliferation and apoptosis.

    PubMed

    Gregoraszczuk, Ewa L; Ptak, Anna; Karniewska, Magdalena; Ropstad, Erik

    2008-10-01

    We recently reported on a stimulatory effect of a mixture of persistent organic pollutants (POPs) extracted from the liver oil of Atlantic cod (Gadus morhua) on estradiol (E2) secretion by porcine ovarian follicular cells [Gregoraszczuk EL, Milczarek K, Wójtowicz A, Berg V, Skaare JU, Ropstad E. Steroid secretion following exposure of ovarian follicular cells to three different natural mixtures of persistent organic pollutants (POPs). Reproductive Toxicol 2007;25:58-66]. The objective of the present study was to identify what compound or compounds within this natural mixture could be responsible for the stimulatory action on E2 secretion. Co-cultures of porcine ovarian theca and granulosa cells were exposed for 48h to individual congeners of polychlorinated biphenyls (PCBs) alone or in combination, at environmentally relevant concentrations (PCB153 at 8microg/ml; PCB118 at 3microg/ml; PCB138 at 8microg/ml; PCB180 at 3microg/ml; PCB126 at 8ng/ml; DDT at 5microg/ml; p,p'-DDE at 10microg/ml). At the end of culture media samples were collected and used for cell viability and steroid determination, and cells were used for the measurement of caspase-3 activity. A threefold decrease in E2 secretion was noted when PCB126 was added in combination with PCB153. Only DDT and DDE could reverse the action of PCB126. Stimulatory secretion of E2 occurred in parallel with a decrease in testosterone (T) secretion. Among the single congeners used in the present study, DDE had the strongest stimulatory action on E2 secretion. In conclusion, the present findings indicate that the overall effect on steroid secretion by ovarian follicular cells could be dependent on the concentration of DDE in environmental POPs and that the predicted effect of a mixture based on a sum of independent effects of individual congeners is higher than that noted under the influence of defined mixture. PMID:18692563

  10. Exposure assessment for workers applying DDT to control malaria in Veracruz, Mexico.

    PubMed Central

    Rivero-Rodriguez, L; Borja-Aburto, V H; Santos-Burgoa, C; Waliszewskiy, S; Rios, C; Cruz, V

    1997-01-01

    DDT has systematically been used in sanitation campaigns against malaria in Mexico. To assess chronic occupational exposure, we studied a group of workers dedicated to spraying houses to control malaria vectors in the state of Veracruz. Exposure was directly estimated for a subgroup of 40 workers by measuring DDT metabolites in adipose tissue samples and indirectly estimated for 331 workers by using a questionnaire to determine their occupational history. Participants ranged in age from 20 to 70 years, and 80% of the workers had been employed in the sanitation campaign for at least 20 years. The mean concentrations of extractable lipids found in adipose tissue samples were as follows: total DDT, 104.48 micrograms/g; p,p'-DDE, 60.98 micrograms/g; p,p'-DDT, 31.0 micrograms/g; o,p'-DDT, 2.10 micrograms/g; and p,p'-DDD, 0.95 microgram/g. The DDT metabolite p,p'-DDE was selected as the indicator of chronic exposure. An index of chronic occupational exposure was constructed according to worker position and based on the historical duration and intensity of DDT application. A linear model including this index, the use of protective gear, and recent weight loss explained 55% of the variation of p,p'-DDE concentrations in adipose tissue. By this model, the predicted values of p,p'-DDE concentration in adipose tissue for the 331 workers are between 9.56 micrograms/g and 298.4 micrograms/g of fat, with a geometric mean of 67.41 micrograms/g. These high levels of DDT in adipose tissue call for exposure prevention programs and the promotion of more secure application measures and hygiene. We also discuss the use of indirect measures of DDT exposure in epidemiological studies of health effects. PMID:9074888

  11. Organochlorine residues in bats after a forest spraying with DDT

    USGS Publications Warehouse

    Henny, C.J.; Maser, C.; Whitaker, J.O., Jr.; Kaiser, T.E.

    1982-01-01

    Background levels of DDT and its metabolites (ZDDT) were extremely low or not detected in five species of forest-dwelling bats in northeastern Oregon, i.e., areas not sprayed with DDT in 1974. Other organochlorine pesticides were rarely found and no polychlotinated biphenyls (PCBs) were detected at any time during the study. Four of five species of bats showed significant changes in Z:DDT residues in, their carcasses following the single DDT spray application. Myotis californicus and M. volans showed the highest postspray carcass residues, 6.90 and 6.21 ppm (wet weight). respectively. Lasionycteris noctivagans and Eptesicus fuscus also showed an increase; however, M. evotis exhibited no significant postspray change. By 1977 (3 years postspray), residues declined and only M. californicus and M. volans contained levels that were significantly above those in the nonspray (control) area. We are uncertain if the elevated residue levels resulting from the DDTspray project adversely affected any of the bats. An attempt to relate bat catcass ZDDT residues to food habits, through analysis of stomach contents, yielded no clear relationships.

  12. 40 CFR 721.2287 - DDT (Dichlorodiphenyltrichloroethane).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false DDT (Dichlorodiphenyltrichloroethane... Substances § 721.2287 DDT (Dichlorodiphenyltrichloroethane). (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance DDT (dichlorodiphenyltrichloroethane) (CAS No....

  13. 40 CFR 721.2287 - DDT (Dichlorodiphenyltrichloroethane).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false DDT (Dichlorodiphenyltrichloroethane... Substances § 721.2287 DDT (Dichlorodiphenyltrichloroethane). (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance DDT (dichlorodiphenyltrichloroethane) (CAS No....

  14. 40 CFR 721.2287 - DDT (Dichlorodiphenyltrichloroethane).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false DDT (Dichlorodiphenyltrichloroethane... Substances § 721.2287 DDT (Dichlorodiphenyltrichloroethane). (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance DDT (dichlorodiphenyltrichloroethane) (CAS No....

  15. Dechlorination of DDT by Aerobacter aerogenes

    USGS Publications Warehouse

    1966-01-01

    Dechlorination of DDT to DDD in higher animals requires the presence of molecular oxygen, but in microorganisms the presence of oxygen hinders dechlorination. In cell-free preparations of Aerobacter aerogenes, the use of selected metabolic inhibitors indicated that reduced Fe(II) cytochrome oxidase was responsible for DDT dechlorination. This finding may possibly explain. the persistence of DDT residues in soils and sediments.

  16. 40 CFR 721.2287 - DDT (Dichlorodiphenyltrichloroethane).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false DDT (Dichlorodiphenyltrichloroethane... Substances § 721.2287 DDT (Dichlorodiphenyltrichloroethane). (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance DDT (dichlorodiphenyltrichloroethane) (CAS No....

  17. 40 CFR 721.2287 - DDT (Dichlorodiphenyltrichloroethane).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false DDT (Dichlorodiphenyltrichloroethane... Substances § 721.2287 DDT (Dichlorodiphenyltrichloroethane). (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance DDT (dichlorodiphenyltrichloroethane) (CAS No....

  18. p,p\\'-Dichlorodiphenyltrichloroethane (DDT)

    Integrated Risk Information System (IRIS)

    p , p ' - Dichlorodiphenyltrichloroethane ( DDT ) ; CASRN 50 - 29 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard

  19. Bioremediation of Cd-DDT co-contaminated soil using the Cd-hyperaccumulator Sedum alfredii and DDT-degrading microbes.

    PubMed

    Zhu, Zhi-qiang; Yang, Xiao-e; Wang, Kai; Huang, Hua-gang; Zhang, Xincheng; Fang, Hua; Li, Ting-qiang; Alva, A K; He, Zhen-li

    2012-10-15

    The development of an integrated strategy for the remediation of soil co-contaminated by heavy metals and persistent organic pollutants is a major research priority for the decontamination of soil slated for use in agricultural production. The objective of this study was to develop a bioremediation strategy for fields co-contaminated with cadmium (Cd), dichlorodiphenyltrichloroethane (DDT), and its metabolites 1, 1-dichloro-2, 2-bis (4-chlorophenyl) ethylene (DDE) and 1, 1-dichloro-2, 2-bis (4-chlorophenyl) ethane (DDD) (DDT, DDE, and DDD are collectively called DDs) using an identified Cd-hyperaccumulator plant Sedum alfredii (SA) and DDT-degrading microbes (DDT-1). Initially, inoculation with DDT-1 was shown to increase SA root biomass in a pot experiment. When SA was applied together with DDT-1, the levels of Cd and DDs in the co-contaminated soil decreased by 32.1-40.3% and 33.9-37.6%, respectively, in a pot experiment over 18 months compared to 3.25% and 3.76% decreases in soil Cd and DDs, respectively, in unplanted, untreated controls. A subsequent field study (18-month duration) in which the levels of Cd and DDs decreased by 31.1% and 53.6%, respectively, confirmed the beneficial results of this approach. This study demonstrates that the integrated bioremediation strategy is effective for the remediation of Cd-DDs co-contaminated soils. PMID:22868749

  20. Risk assessment for children exposed to DDT residues in various milk types from the Greek market.

    PubMed

    Tsakiris, Ioannis N; Goumenou, Marina; Tzatzarakis, Manolis N; Alegakis, Athanasios K; Tsitsimpikou, Christina; Ozcagli, Eren; Vynias, Dionysios; Tsatsakis, Aristidis M

    2015-01-01

    The occurrence of residues of DDT and its metabolites was monitored in 196 cow milk samples of various pasteurized commercial types collected from the Greek market. Residue levels were determined by GC-MS analysis. In 97.4% of the samples at least one DDT isomer or one of the DDT metabolites was detected, in levels not exceeding the maximum permitted residue level by the EU. Hazard Index for both carcinogenic and non-carcinogenic effects was estimated under two assumptions: a) using DDT concentrations from positive samples and b) imputing LOD/2 as an arbitrary concentration for negative samples. No statistically significant differences in detected or summed residue (p > 0.05) concentrations between different milk types were observed, with the exception of specific metabolites of DDT in some milk types. Exposure assessment scenarios were developed for children aged 1, 3, 5, 7 and 12 years old based on estimated body weights and daily milk consumption. Hazard Indices for non-carcinogenic effects were below 0.109 covering also carcinogenic effects according to WHO approach. The cancer risk values for carcinogenic effects according to the US EPA Cancer Benchmark Concentration approach, ranged from 0.4 to 18. For both effects the highest values were calculated for the 1- to 3-year-old age groups. PMID:25449197

  1. EFFECTS OF DDT SEDIMENT-CONTAMINATION ON MACROFAUNAL COMMUNITY STRUCTURE AND COMPOSITION IN SAN FRANCISCO BAY

    EPA Science Inventory

    The objectives of this study were to determine the effects of sediment contamination on the benthic macrofauna and to predict macrofaunal changes following remediation at a Superfund (uncontrolled hazardous waste) site in San Francisco Bay, CA, USA. DDT and its metabolites (sumDD...

  2. Perinatal Exposure of Mice to the Pesticide DDT Impairs Energy Expenditure and Metabolism in Adult Female Offspring

    PubMed Central

    La Merrill, Michele; Karey, Emma; Moshier, Erin; Lindtner, Claudia; La Frano, Michael R.; Newman, John W.; Buettner, Christoph

    2014-01-01

    Dichlorodiphenyltrichloroethane (DDT) has been used extensively to control malaria, typhus, body lice and bubonic plague worldwide, until countries began restricting its use in the 1970s. Its use in malaria control continues in some countries according to recommendation by the World Health Organization. Individuals exposed to elevated levels of DDT and its metabolite dichlorodiphenyldichloroethylene (DDE) have an increased prevalence of diabetes and insulin resistance. Here we hypothesize that perinatal exposure to DDT disrupts metabolic programming leading to impaired metabolism in adult offspring. To test this, we administered DDT to C57BL/6J mice from gestational day 11.5 to postnatal day 5 and studied their metabolic phenotype at several ages up to nine months. Perinatal DDT exposure reduced core body temperature, impaired cold tolerance, decreased energy expenditure, and produced a transient early-life increase in body fat in female offspring. When challenged with a high fat diet for 12 weeks in adulthood, female offspring perinatally exposed to DDT developed glucose intolerance, hyperinsulinemia, dyslipidemia, and altered bile acid metabolism. Perinatal DDT exposure combined with high fat feeding in adulthood further impaired thermogenesis as evidenced by reductions in core temperature and in the expression of numerous RNA that promote thermogenesis and substrate utilization in the brown adipose tissue of adult female mice. These observations suggest that perinatal DDT exposure impairs thermogenesis and the metabolism of carbohydrates and lipids which may increase susceptibility to the metabolic syndrome in adult female offspring. PMID:25076055

  3. DDT contamination in selected estuarine and coastal marine finfish and shellfish of New Jersey.

    PubMed

    Kennish, M J; Ruppel, B E

    1996-08-01

    Analysis of DDT contamination in selected finfish and shellfish species from estuarine and coastal marine waters of New Jersey (USA) reveals consistently highest organochlorine pesticide levels in samples from the north and northeast regions of the state. The mean concentrations of DDT and its metabolites, DDE and DDD, in bluefish, striped bass, weakfish, and blue crabs collected at 27 stations throughout the state between 1988 and 1991 ranged from <25 to >300 microg/kg wet weight (wet wt). Gas chromatographic analysis of 175 tissue samples from these four species showed that the highest levels of DDTs (DDT plus DDE and DDD), exceeding 300 microg/kg wet wt, occurred in blue crabs (hepatopancreas) from the Hudson-Newark-Raritan Bay complex in the northeast region. Lower mean concentrations of DDTs (<200 microg/kg wet wt) were recorded in tissue samples of these species from all other regions of the state. The lowest levels of DDT contamination (mean <110 microg/kg wet wt) were found in samples from the south coast region. The greatest impact of DDT contamination is nearby metropolitan areas of the state, although the total concentrations of DDT in tissue samples from these areas are far less than the U.S. Food and Drug Administration action level of 5,000 microg/kg wet wt for this contaminant. PMID:8781078

  4. 4,4'-Dichlorodiphenyltrichloroethane (DDT) and 4,4'-dichlorodiphenyldichloroethylene (DDE) promote adipogenesis in 3T3-L1 adipocyte cell culture.

    PubMed

    Kim, Jonggun; Sun, Quancai; Yue, Yiren; Yoon, Kyong Sup; Whang, Kwang-Youn; Marshall Clark, J; Park, Yeonhwa

    2016-07-01

    4,4'-Dichlorodiphenyltrichloroethane (DDT), a chlorinated hydrocarbon insecticide, was extensively used in the 1940s and 1950s. DDT is mainly metabolically converted into 4,4'-dichlorodiphenyldichloroethylene (DDE). Even though most countries banned DDT in the 1970s, due to the highly lipophilic nature and very stable characteristics, DDT and its metabolites are present ubiquitously in the environment, including food. Recently, there are publications on relationships between exposure to insecticides, including DDT and DDE, and weight gain and altered glucose homeostasis. However, there are limited reports regarding DDT or DDE and adipogenesis, thus we investigated effects of DDT and DDE on adipogenesis using 3T3-L1 adipocytes. Treatment of DDT or DDE resulted in increased lipid accumulation accompanied by increased expression of CCAAT/enhancer-binding protein α (C/EBPα), peroxisome-proliferator activated receptor-γ (PPARγ), fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), adipose triglyceride lipase, and leptin. Moreover, treatment of DDT or DDE increased protein levels of C/EBPα, PPARγ, AMP-activated protein kinase-α (AMPKα), and ACC, while significant decrease of phosphorylated forms of AMPKα and ACC were observed. These finding suggest that increased lipid accumulation caused by DDT and DDE may mediate AMPKα pathway in 3T3-L1 adipocytes. PMID:27265825

  5. Lethal mobilization of DDT by cowbirds

    USGS Publications Warehouse

    Van Velzen, A.C.; Stiles, W.B.; Stickel, L.F.

    1972-01-01

    This study is an experimental demonstration of lethal mobilization of DDT by brown-headed cowbirds (Molothrus ater) and the effects of food deprivation on the distribution and loss of DDT, DDD, and DDE. The principal experimental group consisted of 20 birds fed a dietary dosage of 100 ppm of DDT for 13 days. After 2 days of full rations of untreated food, they were subjected to food restriction. Food was reduced to 43 percent of normal. Seven of the 20 birds died within 4 days. No birds died in the three control groups, treated as follows: ( 1 ) 20 birds fed 100 ppm DDT for 13 days and full rations of untreated food thereafter, (2) 20 birds fed only untreated food but subjected to food restriction, and (3) 20 birds fed full rations of untreated food throughout. In a pilot study, birds were fed 100, 200, or 300 ppm of DDT and subjected to two periods of food restriction, the first of these immediately after dosage ceased and the second 4 months later. DDT-dosed birds from all dosage levels died in each period of food restriction. Before the weight loss that accompanied food restriction, the brains of DDT-dosed birds had concentrations of DDT and DDD that were far below the lethal range. Concentrations increased rapidly to lethal levels. In these birds, DDT in carcasses decreased while DDD increased. DDT-dosed birds that died during food restriction lost 16 percent of their total body burden of DDT + DDD + DDE, 21 percent of their weight, and 81 percent of their fat. The DDT-dosed birds that were subjected to food restriction but survived lost a significantly greater proportion of their body burden of residues than similarly dosed birds not subjected to weight loss. Brain levels of DDT and DDD in birds that died during food restriction soon after dosage did not differ significantly from brain levels of birds that died in a period of food restriction 4 months after dosage. Concentrations of DDE were significantly higher in the latter group, although they were lower

  6. Low DDT residues in plasma of bald eagles (Haliaeetus leucocephalus) wintering in Colorado and Missouri

    USGS Publications Warehouse

    Henny, C.J.; Griffin, C.R.; Stahlecker, D.W.; Harmata, A.R.; Cromartie, E.

    1981-01-01

    Residues of DDT and its metabolites (Z:DDT) in blood plasma from Bald Eagles (Haliaeetus leucocephalus) wintering in Colorado and Missouri were low (0.06-0.14 ?g/g) in 1977 and 1978. Most of the adult wintering birds probably nest in Canada, although a few in Missouri may be from Minnesota or the Great Lakes region. DDE residues in eggs, estimated from those in plasma, were lower than those reported from Saskatchewan in 1969-1972 (4.5 ?g/g vs. 0.67 ?g//g); this suggests reduced environmental contamination.

  7. Electron Donor Substances and Iron Oxides Stimulate Anaerobic Dechlorination of DDT in a Slurry System with Hydragric Acrisols.

    PubMed

    Liu, Cui-Ying; Cade-Menun, Barbara J; Xu, Xiang-Hua; Fan, Jian-Ling

    2016-01-01

    The interactive effects between electron donor substances and iron (Fe) oxides have significant influence on electron transfer and the growth of Fe-reducing bacteria, which may affect the reductive dechlorination of 1,1,1-trichoro-2,2-bis(p-chlorophenyl)ethane (DDT) in soils. To evaluate the roles of volatile fatty acids and Fe(III) oxide in accelerating the reductive dechlorination of DDT in Hydragric Acrisols, a batch anaerobic incubation experiment was conducted in a slurry system with the following seven treatments: sterile soil, control (DDT-contaminated soil), lactic acid, propionic acid, goethite, lactic acid + goethite, and propionic acid + goethite. Results showed that after 20 d of incubation, DDT residues for these treatments decreased by 34, 65, 77, 81, 77, 90, and 92% of the initial quantities, respectively, with 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethane as the dominant metabolite. The application of lactic acid had no significant effect on DDT dechlorination in the first 8 d while the methanogenesis rate increased quickly but accelerated DDT dechlorination after Day 8 while the methanogenesis rate decreased and Fe(II) contents increased. The application of propionic acid enhanced DDT dechlorination rates throughout the incubation. The amendment by goethite stimulated microbial reduction of Fe(III) oxides to generate Fe(II), which was an efficient electron donor, thus accelerating DDT dechlorination significantly in the early incubation period. A synergetic interaction that accelerated DDT dechlorination, either between lactic acid and goethite or between propionic acid and goethite, was obtained. The results will be of great significance to develop efficient in situ remediation technology of DDT-contaminated soil. PMID:26828189

  8. Comparing water, bovine milk, and indoor residual spraying as possible sources of DDT and pyrethroid residues in breast milk.

    PubMed

    Sereda, Barbara; Bouwman, Henk; Kylin, Henrik

    2009-01-01

    The presence of pollutants in human breast milk is of major concern, especially in malaria control areas where 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) is currently used as indoor residual spray (IRS). The levels of DDT and pyrethroids (PYR) were determined in breast milk, bovine milk, and drinking water from northern KwaZulu-Natal, South Africa. Both reference and exposed mothers used the same market food, but the DDT levels in the exposed mothers (mean SigmaDDT 10 microg/g milk fat [mf]) were much higher than for the reference mothers (mean SigmaDDT 1.3 microg/g milk fat). This difference in residue levels indicates uptake from IRS-applied DDT, most likely via air and skin contact, and excludes food as the main source of pollutants. DDT levels in bovine milk (mean SigmaDDT 0.15 microg/g mf) from the exposed area were less than levels in breast milk from the reference area, and lower than the 20 microg/L maximum residue limit (MRL) set by the Food and Agriculture Organization (FAO). Mean SigmaDDT in water was 0.0065 microg/L, much lower then the WHO limit of the sum of all metabolites in drinking water of 1 microg/L, and therefore highly unlikely to have contributed to any extent toward levels in breast milk. Permethrin in breast milk (mean 1.1-1.6 microg/g milk fat) was probably derived from home garden and indoor use, while the other PYR (cypermethrin and cyfluthrin) at lower concentrations were probably derived from food and agricultural exposure. It is postulated that a better understanding of the indoor dynamics of DDT and other insecticides, through a concept of Total Homestead Environment Approach (THEA), is crucial for investigating options of reducing human exposure and uptake under malaria control conditions. PMID:19557612

  9. Features and News. DDT Stands Trial Again

    ERIC Educational Resources Information Center

    Jukes, Thomas H.

    1972-01-01

    Presents an informative account for the layman of the use of DDT as viewed by the government, scientists and courtroom. Considering the allegations and counter-allegations for its use, the article suggests that DDT is not as harmful as projected by agencies. The outcome of the hearings are not included. (PS)

  10. DDT, epigenetic harm, and transgenerational environmental justice

    PubMed Central

    2014-01-01

    Although the environmentally harmful effects of widespread dichlorodiphenyltrichloroethane (DDT) use became well-known following Rachel Carson’s Silent Spring (1962), its human health effects have more recently become clearer. A ban on the use of DDT has been in place for over 30 years, but recently DDT has been used for malaria control in areas such as Africa. Recent work shows that DDT has transgenerational effects in progeny and generations never directly exposed to DDT. These effects have health implications for individuals who are not able to have any voice in the decision to use the pesticide. The transgenerational effects of DDT are considered in light of some widely accepted ethical principles. We argue that this reframes the decision to use DDT, requiring us to incorporate new considerations, and new kinds of decision making, into the deliberative process that determines its ongoing use. Ethical considerations for intergenerational environmental justice are presented that include concern and respect for autonomy, nonmaleficence, and justice. Here, we offer a characterization of the kinds of ethical considerations that must be taken into account in any satisfactory decisions to use DDT. PMID:25086599

  11. Dechlorination of DDT mediated by bimetallic systems.

    PubMed

    Gautam, S K; Sumathi, S

    2006-04-01

    DDT dechlorination efficiencies of bimetallic systems, namely, Mg0-Zn, Mg0-Ni, and Mg0-Co were compared. All the systems transformed DDT with efficiencies exceeding 98% within 24 h. Based on GC-ECD and GC-MS analyses a step-wise and sequential dechlorination of DDT by Mg0-Zn system in 1:1 water acetone phase via 1,1 dichloro, 2,2- bis (p-chlorophenyl) ethane (DDD), 1, chloro, 2,2 bis (p-chlorophenyl) ethane (DDMS) to 2,2 bis (p-chlorophenyl) ethane (DDNS) was noted. Accumulation of DDNS as the end product indicates that all three alkyl chlorine atoms of DDT were removed by Mg0-Zn system. Mg0-Co also showed almost complete removal of DDT in water-acetone phase that was accompanied by the accumulation of DDD followed by a decline in its concentration as a function of time. On the other hand, Mg0-Ni system exhibited inefficient removal of DDT in water-acetone phase. In pure acetone phase, Mg0-Co system and Mg0-Ni dechlorinated DDT with the accumulation of DDE and DDMU as end products following 24 h of reaction. The presence of surfactants or organic solvents is required to ensure solubilization of DDT. Also addition of acid is essential to provide sufficient protons for efficient reductive dechlorination via hydrogenation. Advantage of Mg0 based dehalogenation reactions is that they occur at high rates under ambient temperatures, and pressure and oxygen need not be excluded in the reaction phase. Our studies revealed that Mg0-Zn is the best option among all tested systems due to its high reactivity and low cost, and may be used to treat DDT contaminated water. PMID:16583823

  12. Blood levels of DDT and breast cancer risk among women living in the north of Vietnam.

    PubMed

    Schecter, A; Toniolo, P; Dai, L C; Thuy, L T; Wolff, M S

    1997-11-01

    A positive association has been reported between elevated tissue organochlorines (p,p'-DDT/p,p'-DDE, PCBs, dioxins) and breast cancer in some case-control studies and occupational cohort studies. We previously reported high serum levels of p,p'-DDT and its metabolite p,p'-DDE in women living throughout Vietnam. We report here the results of a small hospital-based case-control study examining the association between blood levels of p,p'-DDT/p,p'-DDE and the risk of invasive breast cancer among residents of the north of Vietnam-an area where insecticides such as p,p'-DDT have been heavily used in the recent past. The study was conducted among patients admitted to a single hospital in the capital city of Hanoi in 1994. Study subjects were 21 women newly diagnosed with invasive adenocarcinoma of the breast, who served as cases, and 21 women of similar age with fibrocystic breast disease, who served as controls. No increase was evident in the relative risk of breast cancer with increasing tertiles of serum concentration of the compounds of interest, even after adjustment for major potential confounders, such as age at menarche, parity, history of lactation, and body weight. These results suggest that recent and past exposure to p,p'-DDT does not play an important role in the etiology of breast cancer among women living in a country with a tropical climate where insecticide use for mosquito control is common. PMID:9419265

  13. DDT Exposure in Utero and Breast Cancer

    PubMed Central

    La Merrill, Michele; Krigbaum, Nickilou Y.; Yeh, Gregory; Park, June-Soo; Zimmermann, Lauren; Cirillo, Piera M.

    2015-01-01

    Context: Currently no direct evidence links in utero dichlorodiphenyltrichloroethane (DDT) exposure to human breast cancer. However, in utero exposure to another xenoestrogen, diethylstilbestrol, predicts an increased breast cancer risk. If this finding extends to DDT, it could have far-reaching consequences. Many women were heavily exposed in utero during widespread DDT use in the 1960s. They are now reaching the age of heightened breast cancer risk. DDT exposure persists and use continues in Africa and Asia without clear knowledge of the consequences for the next generation. Hypothesis: In utero exposure to DDT is associated with an increased risk of breast cancer. Design: This was a case-control study nested in a prospective 54-year follow-up of 9300 daughters in the Child Health and Development Studies pregnancy cohort (n = 118 breast cancer cases, diagnosed by age 52 y and 354 controls matched on birth year). Setting and Participants: Kaiser Foundation Health Plan members who received obstetric care in Alameda County, California, from 1959 to 1967, and their adult daughters participated in the study. Main Outcome Measure: Daughters' breast cancer diagnosed by age 52 years as of 2012 was measured. Results: Maternal o,p′-DDT predicted daughters' breast cancer (odds ratio fourth quartile vs first = 3.7, 95% confidence interval 1.5–9.0). Mothers' lipids, weight, race, age, and breast cancer history did not explain the findings. Conclusions: This prospective human study links measured DDT exposure in utero to risk of breast cancer. Experimental studies are essential to confirm results and discover causal mechanisms. Findings support classification of DDT as an endocrine disruptor, a predictor of breast cancer, and a marker of high risk. PMID:26079774

  14. Long-term persistence of dieldrin, DDT, and heptachlor epoxide in earthworms

    USGS Publications Warehouse

    Beyer, W.N.; Krynitsky, A.J.

    1989-01-01

    Earthworms can accumulate persistent soilborne insecticides and are an important source of contamination of terrestrail wildlife. We treated experimental plots once with dieldrin, DDT, or heptachlor, and measured changes in insecticide concentrations in earthworms over a 20-year period. We estimated 'half-times,' defined as the time for a concentration in earthworms to be reduced by half. Deldrin had a half-time of 5.4 years. DDE, the metabolite of DDT most important to wildlife, increased until the third year and then decreased with a half-time of 5.7 years. Heptachlor epoxide, the metabolite of hepatachlor most important to wildlife, increased until the second year and then decreased with a half-time of 4.3 years. The declining parts of the curves of all three compounds fit exponential decay equations reasonably well. The estimates persistence are relevant to insecticides at low or moderate concentrations in relatively undistrubed soils in temperate climates.

  15. Concentration of PCBs,HCB,DDT, and HCH isomers in the ovaries, mammary gland, and liver of cows

    SciTech Connect

    Sitarska, E.; Klucinski, W.; Faundez, R. |

    1995-12-01

    Persistent organic chlorine compounds such as DDT and its metabolites, hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs) play an important role in chronic poisoning and take part in a number of pathological processes. This study estimates the degree of accumulation of organic Chlorine compounds and polychlorinated biphynyls in the liver, ovaries, and mammary gland tissues of cows.12 refs., 1 fig., 1 tab.

  16. Toxic effects of male Perna viridis gonad exposed to BaP, DDT and their mixture: A metabolomic and proteomic study of the underlying mechanism.

    PubMed

    Song, Qinqin; Zheng, Pengfei; Qiu, Liguo; Jiang, Xiu; Zhao, Hongwei; Zhou, Hailong; Han, Qian; Diao, Xiaoping

    2016-01-01

    Benzo(a)pyrene and dichlorodiphenyltrichloroethane are typical persistent organic pollutants, and also the widespread environmental estrogens with known toxicity towards green mussels Perna viridis. In this study, the toxicological effects of BaP and DDT and their mixture were assessed in green mussel gonads using proteomic and metabolomic approaches. Metabolomics by NMR spectroscopy revealed that BaP did not show obvious metabolite changes in the gonad of male green mussel. DDT mainly caused some disturbance of osmotic regulation and energy metabolism by changing BCAAs, alanine, threonine, arginine, etc., unknown metabolite (3.53 ppm), glycine, homarine and ATP at different levels. However, the mixture of BaP and DDT mainly caused some disturbance in osmotic regulation and energy metabolism by differentially altering branched chain amino acids, glutamate, alanine, arginine, unknown metabolite (3.53 ppm), glycine, 4-aminobutyrate, dimethylglycine, homarine and ATP. The results suggest that DDT alone may cause most of metabolites changes in the mixture exposed male mussel gonad, and the results also show that the male P. viridis gonad was more sensitive to DDT than BaP exposures. Proteomic study showed that BaP, DDT and their mixture may have different modes of action. Proteomic responses revealed that BaP induced signal transduction, oxidative stress, spermatogenesis, etc. in the male green mussel gonad; whereas DDT exposure altered proteins that were associated with signal transduction, oxidative stress, cytoskeleton and cell structure, cellular organization, energy metabolism, etc. However, the mixture of BaP and DDT affected proteins related to cytoskeleton and cell structure, oxidative stress, cellular organization, etc. This research demonstrated that metabolomic and proteomic approaches could better elucidate the underlying mechanism of environmental pollutants gonad toxicity. PMID:26546779

  17. Food consumption and adipose tissue DDT levels in Mexican women.

    PubMed

    Galván-Portillo, Marcia; Jiménez-Gutiérrez, Carlos; Torres-Sánchez, Luisa; López-Carrillo, Lizbeth

    2002-01-01

    This article analyzes food consumption in relation to levels of DDE (the principal metabolite of DDT) in the adipose tissue of 207 Mexican women residing in States with high and low exposure to DDT. Data on the women's dietary habits and childbearing history were obtained from a personal interview. Adipose tissue DDE levels were measured by gas-liquid chromatography and compared by analysis of variance (ANOVA) and multiple linear regression. Adipose tissue DDE levels increased significantly with age (p = 0.005) and residence in coastal areas (p = 0.002) and non-significantly with the consumption of onion, cauliflower, prickly pear, squash blossoms, sweet corn, broad beans, chili pepper sauce, ham, and fish. Even so, during breastfeeding there was a non-significant reduction in these levels. The findings suggest that certain foods serve as vehicles for DDE residues and confirm that breastfeeding is a mechanism for the elimination of this insecticide, which accumulates over the years in the human body. PMID:11923886

  18. Modeling the dynamics of DDT in a remote tropical floodplain: indications of post-ban use?

    PubMed

    Mendez, Annelle; Ng, Carla A; Torres, João Paulo Machado; Bastos, Wanderley; Bogdal, Christian; Dos Reis, George Alexandre; Hungerbuehler, Konrad

    2016-06-01

    Significant knowledge gaps exist regarding the fate and transport of persistent organic pollutants like dichlorodiphenyltrichloroethane (DDT) in tropical environments. In Brazil, indoor residual spraying with DDT to combat malaria and leishmaniasis began in the 1950s and was banned in 1998. Nonetheless, high concentrations of DDT and its metabolites were recently detected in human breast milk in the community of Lake Puruzinho in the Brazilian Amazon. In this work, we couple analysis of soils and sediments from 2005 to 2014 at Puruzinho with a novel dynamic floodplain model to investigate the movement and distribution of DDT and its transformation products (dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD)) and implications for human exposure. The model results are in good agreement with the accumulation pattern observed in the measurements, in which DDT, DDE, and DDD (collectively, DDX) accumulate primarily in upland soils and sediments. However, a significant increase was observed in DDX concentrations in soil samples from 2005 to 2014, coupled with a decrease of DDT/DDE ratios, which do not agree with model results assuming a post-ban regime. These observations strongly suggest recent use. We used the model to investigate possible re-emissions after the ban through two scenarios: one assuming DDT use for IRS and the other assuming use against termites and leishmaniasis. Median DDX concentrations and p,p'-DDT/p,p'-DDE ratios from both of these scenarios agreed with measurements in soils, suggesting that the soil parameterization in our model was appropriate. Measured DDX concentrations in sediments were between the two re-emission scenarios. Therefore, both soil and sediment comparisons suggest re-emissions indeed occurred between 2005 and 2014, but additional measurements would be needed to better understand the actual re-emission patterns. Monte Carlo analysis revealed model predictions for sediments were very sensitive to highly

  19. Biodegradation of ddt (1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane) by the white rot fungus phanerochaete chrysosporium

    SciTech Connect

    Bumpus, J.A.; Aust, S.D.

    1987-01-01

    Extensive biodegradation of 1,1,1-trichloro-2,2bis(4-chlorophenyl)ethane (DDT) by the white rot fungus Phanerochaete chrysosporium was demonstrated by disappearance and mineralization of (14C) DDT in nutrient nitrogen-deficient cultures. Mass balance studies demonstrated the formation of polar and water-soluble metabolites during degradation. Hexane-extractable metabolites identified by gas chromatography-mass spectrometry included 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane(DDD), 2,2,2-trichloro-1,1-bis(4-chlorophenyl)ethanol (dicofol), 2,2-dichloro-1,1-bis(4-chlorophenyl) ethanol (FW-152), and 4,4'-dichlorobenzophenone (DBP). DDD was the first metabolite observed; it appeared after 3 days of incubation and disappeared from culture upon continued incubation. This, as well as the fact that ((14)C) dicofol was mineralized, demonstrates that intermediates formed during DDT degradation are also metabolized. These results demonstrate that the pathway for DDT degradation in P. chrysosporium is clearly different from the major pathway proposed for microbial or environmental degradation of DDT. Like P. chrysosporium ME-446 and BKM-F-1767, the white rot fungi Pleurotus ostreatus, Phellinus weirii, and Polyporus versicolor also mineralized DDT.

  20. Accumulation, distribution and transformation of DDT and PCBs by Phragmites australis and Oryza sativa L.: I. Whole plant study.

    PubMed

    Chu, W K; Wong, M H; Zhang, J

    2006-01-01

    Glasshouse experiments were conducted to determine the accumulation, distribution and transformation of o,p'-DDT, p,p'-DDT and PCBs by common reed (Phragmites australis) and rice (Oryza sativa L.) under hydroponic conditions. The culture solution was spiked with the organic pollutants and samples were collected daily. Analysis of the plants at harvest showed that both species had removed DDT and PCBs from the solution. DDT appeared to have accumulated within P. australis by both passive adsorption and active absorption. Both o,p'-DDT and p,p'-DDT were transformed within P. australis. DDD was the major metabolite and the transformation was mediated by reductive dehalogenation. Plant long-distance transportation systems may be involved in the translocation of PCBs within P. australis and the affinity of the PCBs for lipids is one of the major factors affecting their uptake and translocation within the plants. Similar but less pronounced results were found in O. sativa and suggest that these wetland plants may be used for the plant-mediated remediation of persistent organic pollutants. PMID:16547765

  1. Inactivation of DDT deposits on mud surfaces*†

    PubMed Central

    Bordas, E.; Downs, W. G.; Navarro, L.

    1953-01-01

    The problem of the inactivation of DDT deposits on dry mud surfaces is presented and its causes outlined. The phenomenon is found to be due to adsorption of the DDT crystals present on the surface; this adsorption appears to be the initial step in the catalytic decomposition of DDT by the iron oxides present in soils, since there is a direct relation between the amount of oxides present and their capacity to inactivate DDT deposits. The DDT-inactivating capacity of soils can be determined by testing them for catalytic activity in the thermal decomposition of DDT. The adsorption of DDT by soil is influenced by environmental relative humidity. Inactivated deposits may be reactivated by increase of the atmospheric humidity. Several substances proposed for the protection of the DDT deposit from inactivation were tested without success. Reference is made, however, to the encouraging findings of some other workers. Limewashing is recommended for the protection of DDT deposits. PMID:13082389

  2. Accelerated anaerobic dechlorination of DDT in slurry with Hydragric Acrisols using citric acid and anthraquinone-2,6-disulfonate (AQDS).

    PubMed

    Liu, Cuiying; Xu, Xianghua; Fan, Jianling

    2015-12-01

    The application of electron donor and electron shuttle substances has a vital influence on electron transfer, thus may affect the reductive dechlorination of 1,1,1-trichoro-2,2-bis(p-chlorophenyl)ethane (DDT) in anaerobic reaction systems. To evaluate the roles of citric acid and anthraquinone-2,6-disulfonate (AQDS) in accelerating the reductive dechlorination of DDT in Hydragric Acrisols that contain abundant iron oxide, a batch anaerobic incubation experiment was conducted in a slurry system with four treatments of (1) control, (2) citric acid, (3) AQDS, and (4) citric acid+AQDS. Results showed that DDT residues decreased by 78.93%-92.11% of the initial quantities after 20days of incubation, and 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethane (DDD) was the dominant metabolite. The application of citric acid accelerated DDT dechlorination slightly in the first 8days, while the methanogenesis rate increased quickly, and then the acceleration effect improved after the 8th day while the methanogenesis rate decreased. The amendment by AQDS decreased the Eh value of the reaction system and accelerated microbial reduction of Fe(III) oxides to generate Fe(II), which was an efficient electron donor, thus enhancing the reductive dechlorination rate of DDT. The addition of citric acid+AQDS was most efficient in stimulating DDT dechlorination, but no significant interaction between citric acid and AQDS on DDT dechlorination was observed. The results will be of great significance for developing an efficient in situ remediation strategy for DDT-contaminated sites. PMID:26702971

  3. DDT-resistance in Anopheles stephensi.

    PubMed

    DAVIDSON, G; JACKSON, C E

    1961-01-01

    In view of the increasing number of reports from different parts of the world indicating resistance to DDT in both adults and larvae of Anopheles stephensi, an important malaria vector, a series of laboratory studies has been carried out on the degree, the pattern and the mode of inheritance of resistance in this species. A DDT-resistant strain from Iraq and a susceptible strain from India were used.In four sets of observations made in the course of tests on both adults and larvae a monofactorial type of inheritance was indicated, and the factor involved was shown to be dependent for its expression on the genetic background.DDT-resistance in A. stephensi appears to be similar in most respects to that in A. sundaicus. PMID:13883789

  4. Enhancement effect of two ecological earthworm species (Eisenia foetida and Amynthas robustus E. Perrier) on removal and degradation processes of soil DDT.

    PubMed

    Lin, Zhong; Li, Xiao-min; Li, Yong-tao; Huang, De-yin; Dong, Jun; Li, Fang-bai

    2012-05-01

    Effects of two ecological earthworm species (epigeic Eisenia foetida and endogeic Amynthas robustus E. Perrier) with different densities (15 and 30 individuals per kg of soil) on the removal of soil 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) with two pollution levels (2 and 4 mg kg(-1)) were investigated. Concentrations of DDT and its metabolites, including 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (DDD), 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (DDE), and 1-chloro-2,2-bis(4-chlorophenyl)ethylene (DDMU), were monitored after 60, 180, and 360 days of incubation. The results obtained showed that both earthworm species can significantly enhance degradation of soil DDT to its metabolites. For E. foetida, the higher earthworm density showed significantly higher rate of DDT degradation than the lower one. Anaerobic reductive dechlorination was the main degradation pathway over 180 days of incubation, while the aerobic dechlorination process was promoted between 180 and 360 days of incubation. Some earthworm amended treatments showed significantly higher microbial biomass carbon and nitrogen than the control, which suggested that earthworms might enhance the microbial degradation of DDT. Both earthworm species would have the potential to be applied to enhance the remediation of agricultural lands polluted by DDT. PMID:22584803

  5. Bird mortality after spraying for Dutch elm disease with DDT

    USGS Publications Warehouse

    Wurster, C.F.; Wurster, D.H.; Strickland, W.N.

    1965-01-01

    In Hanover, New Hampshire, where elms were sprayed with DDT, 151 dead birds were found; 10 dead birds were found in Norwich, Vermont, where no DDT was used. Chemical analyses of dead birds, observation of symptoms of DDT poisoning, and a population decline after spraying all indicate severe mortality among certain species in Hanover.

  6. Optical device for continuous monitoring of DDT residues

    NASA Astrophysics Data System (ADS)

    Sharma, Ashutosh; Sheikh, Sohail H.

    1997-05-01

    A two step filtration based fluorometric device for continuous measurement of DDT residues is developed. The device which exploits the native fluorescence of DDT can be easily adopted to a commercial spectrofluorometer. The device was tested for its use in measuring DDT contamination in soil, potato peel and orange juice extracts and provides a detection limit approximately 1 (mu) M.

  7. The GraVent DDT database

    NASA Astrophysics Data System (ADS)

    Boeck, Lorenz R.; Katzy, Peter; Hasslberger, Josef; Kink, Andreas; Sattelmayer, Thomas

    2016-03-01

    An open-access online platform containing data from experiments on deflagration-to-detonation transition conducted at the Institute of Thermodynamics, Technical University of Munich, has been developed and is accessible at http://www.td.mw.tum.de/ddt. The database provides researchers working on explosion dynamics with data for theoretical analyses and for the validation of numerical simulations.

  8. UPTAKE AND PHYTOTRANSFORMATION OF O,P'-DDT AND P,P'-DDT BY AXENICALLY CULTIVATED AQUATIC PLANTS

    EPA Science Inventory

    The uptake and phytotransformation of o,p'-DDT and p,p'-DDT were investigated in vitro using three axenically cultivated aquatic plants: parrot feather (Mariophyllum aquaticum), duckweed (Spirodela oligorrhiza), and elodea (Elodea canadensis). The decay profile of DDT from the aq...

  9. Influence of a local source of DDT pollution on statewide DDT residues in waterfowl wings, northern Alabama, 1978-79

    USGS Publications Warehouse

    Fleming, W.J.; O'Shea, T.J.

    1980-01-01

    Heavy DDT contamination resulting from a former DDT manufacturing plant in northern Alabama has influenced statewide averages of DDT, DDE, and TDE residues in duck wings tested in the National Pesticide Monitoring Program. In states where contaminant levels in duck wings are high, residue analyses of wings categorized by finer geographic subdivision may be useful in defining the areas of heaviest contamination.

  10. Reconstruction of historical atmospheric deposition of DDT in the Zempoala Lagoon, in the center of Mexico

    USGS Publications Warehouse

    van, Afferden M.; Hansen, A.M.; Fuller, C.C.

    2005-01-01

    Historical trend in deposition of DDT and its metabolites has been reconstructed by analyzing sediment cores of the Zempoala Lagoon, in the center of Mexico. The small watershed of this mountain lagoon is closed, and it is located between 2.800 and 3.700 masl. It ls neither affected by agriculture nor by permanent populations. The Zempoala Lagoon has an average depth of 3.9 mand a maximum depth of 8.8 m. Sediments were extracted with a eore sampler and analyzed by isotope methods (137CS and 2'OPb) for dating. Average sedimentation rate was determined in 0.129 9 cm" yr', corresponding to a maximum age of the 44 cm eore of approximately 60 years. The first presence of total-DDT oecurs in a depth between 28 and 32 cm of the sediment profile, corresponding to the 1960's, with a concentration of 5.3 I1g kg-'. The maximum eoncentration of total-DDT (13.0I1g kg-') occurs in sediment layers representing the late 1970's and beginning 1980's. More recently the concentration decreases towards the present concentration of 1.6 I1g kg-'. This concentration is below most DDT levels reported in recent sediment studies in the USA. The results indicate that the Zempoala Lagoon represents a natural reeipient for studies of the reconstruction of historical trends of atmospheric contaminant deposition in this region. The limitations of the methodology applied, due to the influenee of biodegradation on the definition of correct historical coneentrations of DDT depositions, are demonstrated.

  11. Reproductive effects of occupational DDT exposure among male malaria control workers.

    PubMed Central

    Salazar-García, Félix; Gallardo-Díaz, Esperanza; Cerón-Mireles, Prudencia; Loomis, Dana; Borja-Aburto, Victor H

    2004-01-01

    To assess potential effects of human DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane] exposure, we evaluated the reproductive history of 2,033 workers in the antimalaria campaign of Mexico. Data on occupational exposure to DDT and reproductive outcomes were gathered through a questionnaire, and workers provided information about 9,187 pregnancies. We estimated paternal exposure to DDT before each pregnancy using three approaches: a) a dichotomous indicator for pregnancies before and after exposure began, b) a qualitative index of four exposure categories, and c) an estimation of the DDT metabolite DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene] accumulated in fat. To assess associations, we used logistic regression models that accounted for correlated observations and adjusted for parents' age at each child's birth, exposure to other pesticides, exposure to chemical substances in other employment, smoking, and alcohol consumption. The odds ratio for birth defects comparing pregnancies after and before the first exposure was 3.77 [95% confidence interval (95% CI), 1.19-9.52]. Compared with the lowest quartile of estimated DDE in fat, the ORs were 2.48 (95% CI, 0.75-8.11), 4.15 (95% CI, 1.38-12.46), and 3.76 (95% CI, 1.23-11.44) for quartiles 2, 3, and 4, equivalent to p,p -DDE in fat of 50, 82, and 298 microg/g fat, respectively. No significant association was found for spontaneous abortion or sex ratio. We found an increased risk of birth defects associated with high occupational exposure to DDT in this group of workers. The significance of this association at lower exposure levels found in the general population remains uncertain. PMID:15064158

  12. Insecticides: effects on cutthroat trout of repeated exposure to DDT

    USGS Publications Warehouse

    Allison, Don; Kallman, Burton J.; Cope, Oliver B.; Van Valin, Charles C.

    1963-01-01

    Cutthroat trout were periodically exposed to p, pp-DDT, in acetone solution or in the food. Excessive mortality occurred only in lots treated with high concentrations of DDT, probably as a result of decreased resistance to nonspecific stressors. Surviving fish in these lots were significantly larger than those in the control lot, or in the lots treated with low concentrations of DDT. The number and volume of eggs produced was not reduced by DDT, but mortality among sac fry appeared to be highest in the lots treated with high concentrations. The data suggest that the sublethal concentrations of DDT ordinarily encountered in the environment are unlikely to damage a fishery.

  13. Impact of addition of amendments on the degradation of DDT and its residues partitioned on soil.

    PubMed

    Singh, Swatantra P; Bose, Purnendu; Guha, Saumyen; Gurjar, Suresh K; Bhalekar, Santosh

    2013-08-01

    Market-grade DDT used for mosquito control and other purposes is a mixture of 4,4-DDT, 2,4-DDT and smaller amounts of 4,4-DDD, 2,4-DDD, 4,4-DDE and 4,4-DDMU. All above components (together known as DDTr) are strongly hydrophobic and hence are present in the environment predominantly in the soil/sediment phases. The persistence of DDTr and the feasibility of attenuation of DDTr concentration in soil matrix through addition of amendments is a subject of ongoing interest. The objective of this study was to compare the decline of soil-partitioned DDTr concentration through, (1) the natural attenuation process, (2) enhanced aerobic and anaerobic biodegradation processes involving addition of acclimatized seed and co-metabolites and (3) Nanoscale Zero Valent Iron (NZVI) addition. The extent of decline in soil DDTr concentration in control experiments, where biodegradation and photolysis were excluded, was around 10-15% in ∼100d. Extent of DDTr decline in natural attenuation experiments was 25-30% and 15-20% under aerobic and anaerobic conditions respectively. In enhanced biodegradation experiments, addition of acclimatized seed and/or co-metabolites did not enhance the extent of DDTr attenuation over and above the natural attenuation rates both in aerobic and anaerobic conditions. It thus appeared that biodegradation of DDTr adsorbed on soil was severely limited and controlled by desorption and consequent bioavailability of DDTr in the aqueous phase. In case of NZVI addition, the rate of DDTr degradation was much faster, with 40% decrease in DDTr concentration within 28h of NZVI addition. Here, the faster DDTr degradation may be through direct electron transfer between NZVI particles and DDTr molecules adsorbed on soil. Increase in the concentration of 4,4-DDD and 2,4-DDD during NZVI addition suggest that these compounds are either intermediate or end products of DDT degradation process. PMID:23706893

  14. textbf{Historical Usage Inventories of DDT in China}

    NASA Astrophysics Data System (ADS)

    Qiang, Wang; Lijuan, Zhao; Jianxin, Hu

    2010-05-01

    Dichlorodiphenyltrichloroethane (DDT) is one of organochlorine pesticides and listed as one of the persistent organic pollutants to be reduced and finally eliminated in the Stockholm Convention on Persistent Organic Pollutants, because of its great persistence, toxics, bio-accumulation and potential for long-range transport. It is critical to create national DDT usage/emission inventories for China to carry out source-receptor relation analysis, risk assessment, and other research related to DDT in this country. Chinese inventories of DDT to the year1983 have been published; however, DDT is still being used indirectly in the dicifol producing and being applied for malaria control in case. Therefore it is needed to supplement and update the inventories. DDT production in China can be divided into three phases. Prior to 1965 is the first stage with an annual output of no more than 10,000 tons; 1966-1983 is the second phase. At this stage DDT was produced with an average annual production of 15,500 tons. After 1984 is the third production phase, of which the average annual DDT production was 6,465 tons. Before 1983, DDT was mainly used for agriculture, forestry and pesticides.China used a total of 270,000 tons of DDT during 1951 - 1983. According to China's cropland area, Li Yi-fan create China's DDT usage inventory of 1951-1983. In 1983 the State Council decided to ban DDT producing and DDT is no longer used in agriculture any more, but it is still being used in the producing of dicofol, malaria prevention and treatment anda small amount for export. To this end, this paper calculated theusage inventory of China's DDT from 1984 to 2003. Using sown areas of cotton, apple, citrus, tea and vegetable as surrogate data, usage of dicifolwas calculated, then the usage inventory of DDT resulting from dicofol use and DDT applied for malaria control with prefecture resolution was created. From 1984 to 2003, China used 15,312 tons of DDT, including 12,912 tons of DDT resulting

  15. DDT residues in human milk samples from Delhi, India

    SciTech Connect

    Zaidi, S.S.A.; Bhatnagar, V.K.; Banerjee, B.D.; Balakrishnan, G.; Shah, M.P.

    1989-03-01

    The widespread use of DDT in India has resulted in increased levels of the insecticide in the ecosystem and, therefore, the potential possible health hazards has been voiced. DDT-residues excreted in milk have been reported from different parts of the world; however, very few reports did appear from India. In fact, there is no report on DDT-content in human milk from Delhi area where higher levels of DDT and BHC in human adipose tissues and blood have already been reported. Higher bioaccumulation of DDT might reflect the higher excretion of residues in milk. The authors have, therefore, attempted a systematic study to monitor DDT-residues in human milk samples collected from various hospitals of Delhi (India).

  16. Pesticides and breast cancer risk: a review of DDT, DDE, and dieldrin.

    PubMed Central

    Snedeker, S M

    2001-01-01

    Established risk factors for breast cancer explain breast cancer risk only partially. Hence, there has been interest in evaluating what role environmental chemicals, especially those with evidence of being hormonally active agents, play in breast cancer risk. Organochlorine pesticides have received the most attention because of their persistence in the environment, ability to concentrate up the food chain, continued detection in the food supply and breast milk, and ability to be stored in the adipose tissue of animals and humans. Although several early descriptive studies and a cohort study identified a strong positive association with breast cancer risk and adipose or blood levels of the organochlorine pesticide dichlorodiphenyltrichloroethane (DDT) and/or its metabolite dichlorodiphenyldichloroethylene (DDE), most of the more recent case--control and nested case--control studies have not supported this association. In this review I discuss these findings and explore how exposure to different forms of DDT with varying estrogenicities may have affected the results of these studies. I also address how other factors influence the interpretation of the studies on DDT, DDE, and breast cancer risk. These include the effect of analytic methods, dietary factors, menopausal status, use of different types of control populations, lactation history, estrogen receptor status, ethnic/racial subgroups, breast tumor characteristics, and polymorphisms. I also discuss the emerging research on whether serum levels of the persistent organochlorine insecticide dieldrin are related to breast cancer risk in Danish and American women. Further research needs are also identified. PMID:11250804

  17. Joint toxicity of sediment-associated DDT and copper to a polychaete, Nereis succinea.

    PubMed

    Wang, Fei; Qi, Hong-Xue; You, Jing

    2015-03-01

    As major components in antifouling paints, both dichlorodiphenyltrichloroethane (DDT) and copper are ubiquitous in estuarine sediment and have been detected at high concentrations in the harbors in South China. In the present study joint toxicity between DDT and copper to an estuarine polychaete, Nereis succinea, was examined using bioaccumulation potential, growth impairment and change in lipid peroxidation contents as sub-lethal endpoints. In general, the toxicity of DDXs (DDT and its metabolites) and copper acted independently and copper was more toxic to the lugworms at environmentally relevant concentrations. Nevertheless, co-exposure to copper led to a significant reduction in the bioaccumulation of DDXs when the concentrations of DDXs in sediment were high. The inhibition of DDX bioaccumulation by copper may be partially explained by the decrease in the bioavailability of sediment-associated DDXs which were estimated by biomimetic gut fluid extraction. The saturation of the solubilization agents or the inhibition of protease activity in gut fluid of N. succinea by copper limited the DDX bioavailability and the subsequent bioaccumulation. PMID:25424350

  18. Extinction risk to bird populations caused by DDT exposure.

    PubMed

    Nakamaru, Mayuko; Iwasa, Yoh; Nakanishi, Junko

    2003-10-01

    The impact of toxic chemicals on wild animals and plants can be quantified in terms of the enhanced risk of population extinction. To illustrate a method for doing this, we estimated such impact for two bird species: herring gull (Larus argentatus) in Long Island, NY, and sparrowhawk (Accipiter nisus) in eastern England, when they were exposed to DDT (p,p(')-dichlorodiphenyltrichloroethane) and its metabolites (called DDTs). The method we used is based on a formula of the mean time to population extinction derived for a stochastic differential equation (the canonical model). The intrinsic rate of natural population growth was estimated from an exponentially growing population, and the intensity of the environmental fluctuation was estimated from the magnitude of population size fluctuation. The effect of exposure to DDTs in reducing the population growth rate was evaluated based on an age-structured population model, by assuming that age-specific fertility is density-dependent and sensitive to DDTs exposure, but age-specific survivorship is not. The results are expressed in terms of the risk equivalent--the decrease in carrying capacity K that causes the same enhancement of extinction risk as chemical exposure at a given level. The risk equivalent can be used in mitigation banking. PMID:12946395

  19. Extinction risk to herring gull populations from DDT exposure.

    PubMed

    Nakamaru, Mayuko; Iwasa, Yoh; Nakanishi, Junko

    2002-01-01

    The impact of toxic chemicals on wild animals and plants can be quantified in terms of the enhanced risk of population extinction. To illustrate the method, we estimated it for herring gull (Larus argentatus) populations in Long Island (NY, USA) exposed to DDT (p,p'-dichlorodiphenyltrichloroethane) and its metabolites (abbreviated as DDTs) with a strong biomagnification effect. The method is based on a formula of the mean time to population extinction derived for a stochastic differential equation (the canonical model). The intrinsic rate of natural population growth was estimated from the doubling time of an exponentially growing population and the intensity of the environmental fluctuation from the magnitude of population size fluctuation. The effect of exposure to DDTs in reducing the population growth rate was evaluated based on an age-structured population model by assuming that age-specific fertilities (including chick survivorship) are density dependent and sensitive to DDTs exposure but age-specific survivorships are not. The results are expressed in terms of the risk equivalent-the decrease in the carrying capacity K that causes the same enhancement of extinction risk as chemical exposure at a given level. The high concentration reported in Long Island in the 1960s corresponds to the equivalent loss of carrying capacity by 42.5% when K is 100 (the number of breeding females), and coefficient of variation (CV) = 0.2 (sigma2 = 0.0298) [corrected]. Risk equivalent allows us to compare different risk factors and is useful in mitigation banking. PMID:11804054

  20. An evaluation of the success of dredging as remediation at a DDT-contaminated site in San Francisco Bay, California, USA.

    PubMed

    Weston, Donald P; Jarman, Walter M; Cabana, Gilbert; Bacon, Corinne E; Jacobson, Lisa A

    2002-10-01

    Lauritzen Canal, a portion of San Francisco Bay near Richmond, California, USA, was heavily contaminated with dichlorodiphenyltrichloroethane (DDT) and dieldrin as a result of releases from a pesticide-formulating firm. In 1996 and 1997, 82,000 m3 of contaminated sediment was removed from the canal by dredging. This study evaluated the success of the dredging based largely on body burdens of DDT and its metabolites (sigmaDDT) in resident biota, with some data on sediment- and water-contaminant levels and sediment toxicity testing. Sediment disturbance during dredging introduced a pulse of sigmaDDT into the Lauritzen Canal ecosystem, and body burdens of fish and invertebrates increased 2- to 76-fold, depending on the species. Approximately 1 1/2 years after remediation, 11 of 14 indicators showed contamination comparable with or worse than the contamination that existed prior to dredging. Monitoring of mussels up to four years postdredging suggests some modest improvement, although the sigmaDDT body burden of canal mussels remained far above the norm for San Francisco Bay. The elevated sigmaDDT body burdens in biota that persisted for years after remediation reflect recent exposure and are not merely a result of slow metabolic elimination of the sigmaDDT pulse associated with dredging. Sediment sigmaDDT concentrations were low immediately after dredging, but within months, the canal bottom became covered with a veneer of fine sediment as contaminated as that that had been removed. The source of this material has not been conclusively established, but we suspect it came from slumping and erosion from the flanks of the canal beneath docks and around pilings where dredging was not done. In retrospect, either capping in place or more thorough dredging may have been more successful in reducing pesticide exposure of the biota, although there were difficulties associated with both alternatives. PMID:12371501

  1. Activated carbon amendment as a treatment for residual DDT in sediment from a superfund site in San Francisco Bay, Richmond, California, USA.

    PubMed

    Tomaszewski, Jeanne E; Werner, David; Luthy, Richard G

    2007-10-01

    Pesticide formulators formerly operating at Lauritzen Channel, a portion of San Francisco Bay near Richmond (CA, USA), caused contamination of sediment with dichlorodiphenyltrichloroethane (DDT). The present study evaluated the distribution of residual DDT in channel sediment six years following extensive remedial dredging. High DDT concentrations (up to 252 mg/ kg) were found in Young Bay Mud sampled across the channel. Particle analyses showed most of the contamination is contained in the clay/silt sediment fraction, and desorption tests showed that availability is greater for DDT metabolites than parent DDT. The present study examined the feasibility of using activated carbon amendment to sequester DDT from sediment, including an evaluation of reactivated carbon as a less costly alternative to virgin activated carbons. Treatment success of activated carbon amendment to sediment collected from Lauritzen Channel was measured by reductions in aqueous equilibrium concentrations and uptake in semipermeable membrane devices (SPMDs). Four different activated carbons were tested and, after one month of treatment with 3.2 weight % carbon, DDT aqueous equilibrium concentrations were reduced up to 83% and SPMD uptake was reduced up to 91%. Reactivated carbon was comparable with virgin carbons in all tests. Reduction in SPMD uptake of DDT by treatment with 3.2% reactivated carbon increased to 99% after 26 months of treatment. The effectiveness of activated carbon was dependent on the type, size, dose, and contact time. The results show the potential usefulness of activated carbon amendment as a follow-up remedial technology for management of residuals after dredging contaminated sediment. PMID:17867891

  2. Differential response of DDT susceptible and resistant Drosophila melanogaster strains to DDT and oxidative stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Metabolic DDT resistance in Drosophila melanogaster is associated with increased cytochrome P450 expression. Increased P450 activity is also associated with increased oxidative stress. In contrast, increased glutathione S transferase (GST) expression has been associated with a greater ability of o...

  3. Trophic transfer and effects of DDT in male hornyhead turbot (Pleuronichthys verticalis) from Palos Verdes Superfund site, CA (USA) and comparisons to field monitoring.

    PubMed

    Crago, Jordan; Xu, Elvis Genbo; Kupsco, Allison; Jia, Fang; Mehinto, Alvine C; Lao, Wenjian; Maruya, Keith A; Gan, Jay; Schlenk, Daniel

    2016-06-01

    High concentrations of DDT and metabolitesDDT) have been detected in sediment and the demersal flatfish hornyhead turbot (Pleuronichtys verticalis) collected from Palos Verdes (PV), California, USA, a site contaminated with over 100 metric tons of DDT throughout 1960s-70s. This study was conducted to assess the transfer of ΣDDT from PV-sediment into polychaetes (Neanthes arenaceodentata) and hornyhead turbot, and to investigate if the responses in turbots from two different laboratory exposures mimic those in turbots caught in PV (PV-turbot). Turbot fed PV-sediment-contaminated polychaete for 7 days had liver concentrations of ΣDDT similar to PV-turbot. After 28 days, ΣDDT also accumulated in livers of turbot gavaged with a ΣDDT mixture. In vitro cell bioassays indicated significant increases of 17β-estradiol equivalents (EEQ) in turbot bile extracts as compared to the control in the 7-day study. These responses corresponded to those measured in PV-fish. Glucocorticoid receptor (GR), anti-androgen receptor (anti-AR), estrogen receptor (ER) or aryl hydrocarbon receptor (AhR) activities were also observed in extracts of PV-sediment, and PV-sediment-exposed worm. Anti-AR, AhR and GR activities were significantly higher in PV-sediment than reference sediment (San Diego, SD). Higher transcripts of hepatic VTG, ERα and ERβ were found in PV-turbot than SD-turbot, but were unaltered in fish exposed to sediment-contaminated worms for the 7-day study. In contrast, liver extracts from the 28-day treatment of ΣDDT showed lower EEQ but similar hepatic VTG and ERβ transcripts relative to those of PV-turbot. These data indicated that trophic transfer of sediment-associated DDT in 7-day exposures corresponded to field measurements of DDT residues and in vitro ER bioactivities, but failed to mimic in vivo biological effects observed in field fish. In contrast, treatment with ΣDDT alone for 28 days mimicked in vivo biological effects of DDTs in PV fish, but did not

  4. A preliminary evaluation of the DDT contamination of sediments in lakes Natron and Bogoria (Eastern Rift Valley, Africa).

    PubMed

    Bettinetti, Roberta; Quadroni, Silvia; Crosa, Giuseppe; Harper, David; Dickie, Jennifer; Kyalo, Margaret; Mavuti, Kenneth; Galassi, Silvana

    2011-06-01

    Dichlorodiphenyltrichloroethane (DDT) is still used in Africa for the indoor control of malaria and it may represent a potential hazard for wildlife. The littoral sediments of two alkaline-saline lakes, Natron (Tanzania) and Bogoria (Kenya), in the Eastern Rift Valley, supporting large populations of lesser flamingos (Phoeniconaias minor), were analysed for DDT residues. Physical-chemical analyses (temperature, conductivity, pH and dissolved oxygen) were also performed on the water of the two lakes and in the tributaries of Lake Natron, to evaluate the influence of the environmental variables on pollutant occurrence. At Lake Natron, around 1 km from the sediment collection sites, tree leaves of Acacia tortilis were also collected. The main metabolite found in all sediment samples was pp'DDE, whilst equal concentrations of pp'DDT and pp'DDE were measured in acacia leaves. The levels of DDTs measured in the sediments were within 5.9-30.9 ng g(-1) d.w., reaching the maximum value in a tributary of Lake Natron. On the whole, the contamination of Lake Natron and Lake Bogoria basins seems to be quite moderate. Nevertheless, the pp'DDE/pp'DDT ratio equals 1 in the Acacia tortilis leaves, which makes one suppose that the input of the parent compound was rather recent and could have been from aerial transport or dust from relatively close-by old pesticides storage sites. PMID:21809777

  5. DDT, DDD, AND DDE DECHLORINATION BY ZERO-VALENT IRON

    EPA Science Inventory

    Traditionally, destruction of DDT [1,1,1-trichIoro-2,2-bis(p-chlorophenyl)ethane] for environmental remediation required high-energy processes such as incineration. Here, the capability of powdered zero-valent iron to dechlorinate DDT and related compounds at room tempera...

  6. Is DDT use a public health problem in Mexico?

    PubMed Central

    López-Carrillo, L; Torres-Arreola, L; Torres-Sánchez, L; Espinosa-Torres, F; Jiménez, C; Cebrián, M; Waliszewski, S; Saldate, O

    1996-01-01

    We review the potential impact of DDT on public health in Mexico. DDT production and consumption patterns in Mexico during the last 20 years are described and compared with those in the United States. In spite of the restrictions on DDT use in antimalaria campaigns in Mexico, use of DDT is still higher than in other Latin American countries. We analyzed information from published studies to determine accumulated levels of this insecticide in blood, adipose tissue, and breast milk samples from Mexican women. Current lipid-adjusted DDE levels from women living in Mexico City are 6.66 ppb in mammary adipose tissue and 0.594 ppm in total breast milk. Finally, the methodological limitations of existing epidemiological studies on DDT exposure and breast cancer are discussed. We conclude that DDT use in Mexico is a public health problem, and suggest two solutions: identification of alternatives for the control of malaria and educational intervention to reduce DDT exposure. We also recommend strengthening epidemiological studies to evaluate the association between accumulated DDT levels in adipose tissue and breast cancer incidence among Mexican women. Images Figure 1. Figure 2. Figure 3. PMID:8793339

  7. Reductive dechlorination of DDT to DDD by yeast

    USGS Publications Warehouse

    Kallman, Burton J.; Andrews, Austin K.

    1963-01-01

    Labeled DDD [ 1,1-dichlor-o-2,2-bis(p-chlorophenyl)-ethane] was formed from C14-labeled DDT in the presence of yeast. The formation of DDD from DDE [1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene] was not observed, indicating that a reductive dechlorination of DDT occurs.

  8. Chronic oral DDT toxicity in juvenile coho and chinook salmon

    USGS Publications Warehouse

    Buhler, Donald R.; Rasmusson, Mary E.; Shanks, W.E.

    1969-01-01

    Technical and p,p′-DDT was incorporated into test diets and fed to juvenile chinook and coho salmon for periods as long as 95 days. Pure p,p′-DDT was slightly more toxic to young salmon than was the technical DDT mixture. Chinook salmon appeared to be 2–3 times more sensitive to a given concentration of DDT in the diet than were coho salmon. The size of the fish greatly influenced toxicity, smaller younger fish being more susceptible to a given diet than larger older fish. The dose of DDT accumulated within the median survival time ranged from 27–73 mg/kg for chinook salmon and from 56–72 mg/kg for coho salmon. The extrapolated 90-dose LD50 (Hayes, 1967) for young chinook and coho salmon were 0.0275 and 0.064 mg/kg/day, respectively. Liver size decreased on prolonged feeding with DDT, and carcass lipid content was increased. A severe surface ulceration of the nose region appeared in coho salmon fed DDT over long periods. In addition, an interesting localized degeneration of the distal convoluted tubule was observed in the kidney of coho salmon receiving DDT.

  9. Risk reduction for DDT toxicity and carcinogenesis through dietary modification.

    PubMed

    Jaga, K; Duvvi, H

    2001-06-01

    Organochlorine pesticides, including dichlorodiphenyltrichloroethane (DDT), are an environmental hazard due to their persistent nature and potential health effects. DDT and 1,1,dichloro-2,2,bis(p-chlorophenyl)ethylene (DDE) are lipid-soluble pesticides which accumulate in fatty tissues and are, therefore, more present in fat-containing foods such as meat, fish, milk, cheese and oil than in fruit, vegetables and grain. Scientists have for some time been concerned about the human exposure to DDT and the potential risk of breast cancer due to its oestrogenic activity. The introduction of foods containing chemopreventive agents in the diet could inhibit the oestrogenic effects of DDT and the risk of developing cancer. Phytooestrogens are weak oestrogens found in certain plants such as soybean. They compete with DDT for oestrogen receptors and inhibit the oestrogenic effect of DDT on cultured human breast (MCF) cells. Curcumin, a spice widely used in Indian dishes, has anti-carcinogenic and anti-inflammatory properties. It also inhibits the oestrogenic effects of DDT and is synergistic with phytooestrogens. Indole-3-carbinol, a compound naturally found in cruciferous vegetables, stimulates oestrogen metabolism towards 2-hydroxyoestrone which reduces the oestrogenic response in MCF cells and the risk of breast cancer. Since DDT is lipid soluble and accumulates in adipose tissue it could have a role in lipid metabolism. Would a low fat diet reduce DDT bioaccumulation? A reduction in calories can decrease oestrogen levels and possibly reduce the risk of breast cancer. A dietary modification with the introduction of soy products, curcumin, cruciferous vegetables and low fat could be beneficial in reducing the risk of developing cancer and possibly the effects of DDT. PMID:11467202

  10. Unusual persistence of DDT in some western USA soils

    SciTech Connect

    Hitch, R.K.; Day, H.R. )

    1992-02-01

    Agricultural use of DDT (1,1,1-trichloro-2,2,2-bis (p-chlorophenyl) ethane) was canceled in 1972. By the late 1970's and early 1980's, the National Soils Monitoring Program of the US Environmental Protection Agency (EPA) was consistently finding higher soil residues of the degradate DDE (1,1-dichloro 2,2-bis (p-chlorophenyl) ethylene) than of parent DDT. Similarly, the US Fish and Wildlife Service (FWS) had been finding during the late 1970's that DDT and related compounds had been decreasing in birds throughout the US. During 1984 and 1985, the EPA and the agriculture departments of Texas and New Mexico, in response to the FWS, conducted soil sampling in 13 areas where contaminated birds had been collected. It was agreed that soil samples containing higher levels of DDT than DDE would serve as a possible indicator of illegal DDT use. This was an intensive soil sampling program; over 236 fields were sampled. A controversy developed as to whether high ratios of DDT and DDE might corroborate the accusations of recent illegal use of DDT products. Dell City area soils containing higher levels of DDT than of DDE became classified as suspicious soils. Soils bearing the expected higher level of DDE were dubbed as normal. To resolve the controversy, the authors, in 1989, conducted a DDT soil metabolism study with representative samples of the suspicious and normal soils. It was felt that a soil metabolism study could, once and for all, determine if there was, indeed, something unusual about the rate at which the suspicious soils degrade DDT.

  11. Trends, Long-range Transport and Lifetime of DDT in and over Central Europe

    NASA Astrophysics Data System (ADS)

    Lammel, G.; Dvorská, A.; Stohl, A.; Klánová, J.; Ries, L.

    2009-04-01

    Dichlorophenyltrichloroethane, DDT, and its major metabolites dichlorophenyldichloroethylene, DDE, and dichlorophenyldichloroethane, DDD, are long-lived in the environment (persistent) and circulate since the 1950s. They accumulate along food chains, cause detrimental effects in marine and terrestrial wild life, and pose a hazard for human health. DDT is a multicompartmental substance with only a small mass fraction residing in air. Decreasing concentration trends are recorded in Europe, where the substance has not been used since ?1988 (Holoubek et al., 2007). Transport in the free troposphere is expected by models (Lammel & Semeena, 2005; Semeena et al., 2006), but no observations in the free troposphere had been reported in Europe. The degradation rates of DDT, DDE and DDD are uncertain. In particular, the hydroxyl radical reaction rate coefficients in air are unknown. DDT monitoring data in air at a central European continental background station, Kosetice, Czech Republic, were used in combination with back-trajectories (HYSPLIT model, NOAA) to localize DDT sources in central, western and northern Europe. The decreasing trend continued during recent years, 2004-06. During 2 campaigns at a high mountain site in the Alps (Zugspitze, 2650 m a.s.l.) mean concentrations of 0.23, 0.63 and 0.08 pg m-3 of DDT, DDE and DDD, respectively, were measured in summer and 0.73, 2.22, and 0.52 pg m-3, respectively, in winter. The levels were not lower in free tropospheric air than in boundary layer air. Transport and residence times in air were quantified using Lagrangian particle dispersion model retroplume analyses (FLEXPART model; Stohl et al., 1998). During a stable anti-cyclonic situation photochemical lifetimes corresponded to kOH < 1.5x10-12 cm3 molec-1 s-1 are found for p,p'-DDT, kOH < 0.75x10-12 cm3 molec-1 s-1 for p,p'-DDE and kOH < 1.0x10-12 cm3 molec-1 s-1 for p,p'-DDD. The kOH values for DDE and DDD are significantly lower than estimated (QSAR). References

  12. Occupational exposure to DDT among mosquito control sprayers

    SciTech Connect

    Nhachi, C.F.B.; Kasilo, O.J. )

    1990-08-01

    DDT, a broad action insecticide whose use is restricted or banned in most industrialized countries is still often used for vector control in many tropical and developing countries. Despite the fact that DDT is accumulative and persistant in the ecosystem use of such substitutes as malathion or propoxur is not popular because these increases costs by 3.4 to 8.5 fold. As such DDT is economically attractive to poorer countries. As far as can be ascertained no systemic poisoning has resulted from occupational exposure to DDT. Due to the large particle size, the amount of DDT inhaled by workers is far less than the amount reaching exposed portions of skin. As such occupational exposure is mainly dermal or tropical. Occupational exposure to DDT studies have been done before. The present study is an analysis of some characteristics, (i.e. age, body size, relationship between plasma vitamin A and DDE levels, and smoking habits), of occupational exposure to DDT among spraymen in a Zimbabwe population.

  13. Bird mortality following DDT spray for Dutch elm disease

    USGS Publications Warehouse

    Wurster, D.H.; Wurster, C.F.; Strickland, W.N.

    1965-01-01

    Avian populations in Hanover, N. H., a town that has sprayed its elms with DDT for many years in an attempt to control Dutch elm disease, were compared with those in Norwich, Vt., a town 1 mile (1.6 km) west of Hanover that has never sprayed. Hanover applied 109 lb DDT/acre (2.1 kg/hectare) in April 1963, then used Methoxychlor in April 1964. Population surveys were taken regularly during spring and early summer of these years, dead birds were collected in both towns, and 106 birds were analyzed for DDT, DDE, and DDD. Severe mortality of both resident and migrant birds occurred in Hanover during spring 1963, and the evidence implicates DDT as its cause. Robin loss was estimated at 70% of the resident population, or 350 to 400 individuals, but mortality among other species of widely varied feeding habits was also substantial. Feeding habits suggest that some birds acquired the toxicant by eating living insects carrying DDT, presenting the paradox of survival of the intended DDT victims, and death, instead, of insectivorous birds. Organ and whole bird analyses are presented and criteria for establishing cause of death are discussed. Most of the DDT had been converted to DDE and DDD, and residues were found in all organs analyzed. Robin mortality was reduced, but not eliminated following Methoxychlor application in 1964; these losses were believed caused by residual DDT in the soil. There was no evidence DDT poisoning among other species in 1964, though the dead birds collected were not analyzed.

  14. Total DDT and dieldrin content of human adipose tissue

    SciTech Connect

    Ahmad, N.; Harsas, W.; Marolt, R.S.; Morton, M.; Pollack, J.K.

    1988-12-01

    As far as the authors could ascertain only 4 well-documented analytical studies have been carried out in Australia determining the total DDT and dieldrin content of human adipose tissue. The latest of these studies was published over 16 years ago. Therefore it is timely and important to re-examine the total DDT and dieldrin concentration within the adipose tissue of the Australian population. The present investigation has analyzed 290 samples of human adipose tissue obtained from Westmead Hospital situated in an outer suburb of Sydney, New South Wales for their content of total DDT and dieldrin.

  15. Pd-loaded magnetic mesoporous nanocomposites: A magnetically recoverable catalyst with effective enrichment and high activity for DDT and DDE removal under mild conditions.

    PubMed

    Tian, Hua; Chen, Jun; He, Junhui; Liu, Feng

    2015-11-01

    1,1,1-Trichloro-2,2-bis(4-chlorophenyl) ethane (DDT), an organochlorine pollutant, is highly persistent in environment and responsible for many ecological and health damages. Although remediation and degradation of DDT and its metabolites in soil and water by microorganisms and abiotic techniques can be accomplished, success is often accompanied by rigorous reaction conditions, such as anaerobic system, explosive gases, high pressure or temperature, and illumination. Here a triple-functional nanocomposite was prepared by integrating superparamagnetic Fe3O4 and palladium (Pd) nanoparticles onto mesoporous Fe3O4@nSiO2@mSiO2 nanospheres. These magnetic mesoporous materials display excellent capabilities of capturing and catalytically degrading DDT in water. Over these nanocomposites, DDT and its metabolite, 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (DDE) could be quickly enriched and completely degraded at as low as 150 °C. The nanocomposites can be magnetically separated from the dispersion after adsorption, and then be easily regenerated which is accompanied by catalytic reaction. The whole treatment process is convenient, energy-saving, and just requires ambient pressure and mild reaction conditions. PMID:26188725

  16. Atomic elucidation of the cyclodextrin effects on DDT solubility and biodegradation.

    PubMed

    Ren, Baiping; Zhang, Mingzhen; Gao, Huipeng; Zheng, Jie; Jia, Lingyun

    2016-07-14

    DDT (1,1,1-trichloro-2.2-bis(p-chlorophenyl)ethane), one of the most abused insecticides, is a highly hazardous component for both human health and environmental applications. The biodegradation of DDT into non-toxic, environmentally benign components is strongly limited by the poor bioavailability of DDT. In this work, we combined experiments and molecular simulations to examine the effect of three cyclodextrins (α-, β-, and γ-CD) on their structure-specific interactions with DDT, specifically in relation to DDT solubility and biodegradability. It was found that all three CDs were able to bind to DDT with their inner hydrophobic cavity and different binding affinities and orientations, demonstrating their ability to improve DDT solubility. Different from the strong binding between DDT and β-/γ-CDs via a fully DDT bury mode, α-CD had a relatively weak binding with DDT via a partial DDT bury mode, which allowed DDT to be readily disassociated from α-CD at the lipid membrane interface, followed by DDT permeation into and across the cell membrane. The different binding modes between DDT and CDs explain why only α-CD can promote the bioavailability and biodegradation of DDT by simultaneously increasing its aqueous solubility and membrane interaction. This work provides structural-based binding information for the further modification and optimization of these three CDs to enhance their solubility and biodegradability of DDT. PMID:27301608

  17. o,p'-DDT induces cyclooxygenase-2 gene expression in murine macrophages: Role of AP-1 and CRE promoter elements and PI3-kinase/Akt/MAPK signaling pathways

    SciTech Connect

    Han, Eun Hee; Kim, Ji Young; Kim, Hyung-Kyun; Hwang, Yong Pil; Jeong, Hye Gwang

    2008-12-01

    Dichlorodiphenyltrichloroethane (DDT) has been used as an insecticide to prevent the devastation of malaria in tropical zones. However, many reports suggest that DDT may act as an endocrine disruptor and may have possible carcinogenic effects. Cyclooxygenase-2 (COX-2) acts as a link between inflammation and carcinogenesis through its involvement in tumor promotion. In the present study, we examined the effect of o,p'-DDT on COX-2 gene expression and analyzed the molecular mechanism of its activity in murine RAW 264.7 macrophages. Exposure to o,p'-DDT markedly enhanced the production of prostaglandin E{sub 2} (PGE{sub 2}), a major COX-2 metabolite, in murine macrophages. Furthermore, o,p'-DDT dose-dependently increased the levels of COX-2 protein and mRNA. Transfection with human COX-2 promoter construct, electrophoretic mobility shift assays and DNA-affinity protein-binding assay experiments revealed that o,p'-DDT activated the activator protein 1 (AP-1) and cyclic AMP response element (CRE) sites, but not the NF-{kappa}B site. Phosphatidylinositol 3 (PI3)-kinase, its downstream signaling molecule, Akt, and mitogen-activated protein kinases (MAPK) were also significantly activated by the o,p'-DDT-induced AP-1 and CRE activation. These results demonstrate that o,p'-DDT induced COX-2 expression via AP-1 and CRE activation through the PI3-K/Akt/ERK, JNK, and p38 MAP kinase pathways. These findings provide further insight into the signal transduction pathways involved in the carcinogenic effects of o,p'-DDT.

  18. Current implications of past DDT indoor spraying in Oman.

    PubMed

    Booij, Petra; Holoubek, Ivan; Klánová, Jana; Kohoutek, Jiří; Dvorská, Alice; Magulová, Katarína; Al-Zadjali, Said; Čupr, Pavel

    2016-04-15

    In Oman, DDT was sprayed indoors during an intensive malaria eradication program between 1976 and 1992. DDT can remain for years after spraying and is associated with potential health risk. This raises the concern for human exposure in areas where DDT was used for indoor spraying. Twelve houses in three regions with a different history of DDT indoor spraying were chosen for a sampling campaign in 2005 to determine p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT), p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and p,p'-dichlorodiphenyldichloroethane (p,p'-DDD) levels in indoor air, dust, and outdoor soil. Although DDT was only sprayed indoor, p,p'-DDT, p,p'-DDE and p,p'-DDD were also found in outdoor soil. The results indicate that release and exposure continue for years after cessation of spraying. The predicted cancer risk based on concentrations determined in 2005, indicate that there was still a significant cancer risk up to 13 to 16years after indoor DDT spraying. A novel approach, based on region-specific half-lives, was used to predict concentrations in 2015 and showed that more than 21years after spraying, cancer risk for exposure to indoor air, dust, and outdoor soil are acceptable in Oman for adults and young children. The model can be used for other locations and countries to predict prospective exposure of contaminants based on indoor experimental measurements and knowledge about the spraying time-schedule to extrapolate region-specific half-lives and predict effects on the human population years after spraying. PMID:26820926

  19. Spermatogenesis in bald eagles experimentally fed a diet containing DDT

    USGS Publications Warehouse

    Locke, L.N.; Chura, N.J.; Stewart, P.A.

    1966-01-01

    When Bald Eagles were fed DDT in the diet at the level of 10 ppm (dry weight basis) for periods of 60 and 120 days, there was no interference with spermatogenic activity. Degenerative testicular changes were produced only by levels of DDT that produced abnormal neurological signs and usually resulted in death. Histological examination of these testes indicates that Bald Eagles have a seasonal testicular cycle similar to that reported for many other birds of the Northern Hemisphere.

  20. DDT of hot, thermally damaged PBX 9501 in heavy confinement

    SciTech Connect

    Parker, Gary R; Dickerson, Peter M; Asay, Blaine W; Mc Afee, John M

    2010-01-01

    The research presented examines DDT of cylinders of PBX 9501 damaged above 180 C in heavy confinement for 0-3 hours and end-ignited or ramped until self-ignition (cookoff) occurred. Progression of luminous reaction was observed by streak photography through a glass-filled slit running the length of the cylinder. Post-mortem analysis of the steel DDT tubes was also done for correlation with the optical records. Results indicate that repeatable, Type I DDT was observed to occur in hot, thermally damaged PBX 9501 with low levels of porosity. It was demonstrated that multiple parameters affect DDT behavior, most likely in a coupled fashion. These parameters are porosity, ignition temperature and thermal soak duration. Conditions leading up to cookoff were shown to sensitize the HE to DDT by increasing likelihood and decreasing run length. Over the range of porosities (0-37%) and ignition temperatures (180-235 C), run lengths and detonation velocities varied, respectively, from approximately 22-109 mm and 6.0-8.3 mm {micro}s{sup -1}. This work fills a valuable and realistic space in the understanding of high explosive violent reaction, including DDT, in abnormal thermal environments.

  1. Excretion of radioactivity following the intraperitoneal administration of /sup 14/C-DDT, /sup 14/C-DDD, /sup 14/C-DDE and /sup 14/C-DDMU to the rat and Japanese Quail

    SciTech Connect

    Fawcett, S.C.; Bunyan, P.J.; Huson, L.W.; King, L.J.; Stanley, P.I.

    1981-09-01

    A study in progress to examine the metabolic fate of DDT in birds and mammals is discussed. The first phase of the study, which is reported in this article, has been to establish the rate of excretion of ratioactivity following the intraperitoneal administrations of /sup 14/C-DDT, /sup 14/C-DDE, /sup 14/C-DDD, and /sup 14/C-DDMU to male rats and male Japanese quail. The mean values from the three animals in each experimental group for the amount of radioactivity excreted daily are given, and it was found that the rats excreted the radioactivity administered as DDT, DDD, and DDE substantially faster than did the quail. DDMU was excreted relatively rapidly and at similar rates. This finding suggests that apparent differences in the rates of excretion of DDT by birds and mammals probably arise from differences in the conversion of DDT to DDD or DDE or in the degradation of these metabolites to DDMU. The Japanese quail differ from the rats in excreting substantial amounts of unchanged DDT, DDE, and DDD, which probably reflects the inability of the Japanese quail to readily metabolise these compounds.

  2. Characterization of a bacterial strain capable of degrading DDT congeners and its use in bioremediation of contaminated soil.

    PubMed

    Fang, Hua; Dong, Bin; Yan, Hu; Tang, Feifan; Yu, Yunlong

    2010-12-15

    A bacterial strain DDT-6 (D6) capable of utilizing dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethane (DDD), and dichlorodiphenyldichloroethylene (DDE) (DDTs) as its sole carbon and energy source was isolated and identified as Sphingobacterium sp. The degradation of DDTs by strain D6 in mineral salt medium and in field soil was investigated. The half-lives of the degradation of DDTs increased with increasing concentration ranging from 1 to 50 mg L(-1). Favorable degradation conditions for DDTs by strain D6 were found to be pH 7.0 and 30°C. The degradation of DDTs by strain D6 was found to be statistically significantly enhanced (p ≤ 0.05) by the addition of glucose. Based on the metabolites detected, a pathway was proposed for DDT degradation in which it undergoes dechlorination, hydrogenation, dioxygenation, decarboxylation, hydroxylation, and phenyl ring-cleavage reactions to complete the mineralization process. The addition of strain D6 into the contaminated soils was found to statistically significantly enhance (p ≤ 0.05) the degradation of DDTs. The results indicate that the isolate D6 can be used successfully for the removal or detoxification of residues of DDTs in contaminated soil. PMID:20828928

  3. Metabolism of carbaryl, chloropyrifos, DDT, and parathion in the European corn borer: effects of microsporidiosis on toxicity and detoxication

    SciTech Connect

    Tetreault, G.E.

    1985-01-01

    An investigation was conducted to examine the effects of microsporidiosis on an insect's response to insecticide intoxication. Healthy European corn borer, Ostrinia nubilalis, larvae and those heavily infected with the microsporidian pathogen, Nosema pyrausta, were bioassayed with ten insecticides. The compounds used were carbaryl, carbofuran, chlorophrifos, DDT, diazinon, fonofos, methomyl, parathion, permethrin, and terbufos. Third instar larvae were used for topical bioassays. The compounds carbaryl, carbofuran, chlorophrifos, methomyl and terbufos were found to be significantly more toxic to diseased insects than healthy insects at the 0.05 probability level. To examine the effect of Nosema pyrausta infection on the European corn borer's ability to detoxify insecticides, /sup 14/C ring-labeled carbaryl, chlorophrifos, DDT, and parathion were topically applied to fourth instar larvae. Qualitative differences between healthy and diseased insects were found in the metabolic pathways of carbaryl, DDT, and parathion. The degradative fate of chlorophrifos was the same in both groups. Quantitatively, each insecticide penetrated diseased larvae faster. This resulted in larger amounts of the applied dose of parent compound and metabolites being found in the feces from diseased insects. Conversely, healthy insects had more of these materials present in the body and associated with the cuticle.

  4. Distributions, sources, and ecological risks of DDT-related contaminants in water, suspended particulate matter, and sediments from Haihe Plain, Northern China.

    PubMed

    Wang, Yan; He, Wei; Qin, Ning; He, Qi-Shuang; Kong, Xiang-Zhen; Tao, Shu; Xu, Fu-Liu

    2013-02-01

    The residual levels of dichlorodiphenyltrichloroethane (DDT) and its metabolites (DDXs, including p,p'-DDT, DDD, and DDE) in water, suspended particulate matter (SPM), and sediments from major rivers, lakes, and reservoirs in Haihe Plain were measured with a gas chromatograph equipped with a (63)Ni microelectron capture detector. In the fall of 2004, the contents of the total DDXs in the water and SPM were 0.29 ± 0.69 ng L(-1) and 423.13 ± 577.85 ng g(-1) dry wt., respectively. In the spring of 2005, the total DDXs were 0.36 ± 0.91 ng L(-1) for water and 35.93 ± 62.65 ng g(-1) dry wt. for SPM. The average concentration of DDXs for sediments was 7.10 ± 7.57 ng g(-1) dry wt. during the two seasons. The Eastern-Hebei-Province Coastland River System was the most polluted, which was mainly attributable to the extensive use of DDT pesticide and dicofol in that system. Recent DDT inputs still occur in some regions, as indicated by DDT/(DDD + DDE) > 1 at 29-36 % of the sites for water and 55-61 % of the sites for SPM. The potential ecological risks of DDT in the water were assessed using a species sensitivity distribution model. Only shrimp and crabs were found to have potentially affected fraction values of 1.63 × 10(-3) to 2.27 × 10(-4), with probabilities beyond the hazardous concentration for 5 % of species (HC5) values of 1.90-2.56 %, suggesting only slight risks. DDXs in the sediments of some sites were also of potential risk to benthic organism based on consensus-based sediment quality guidelines. PMID:22580748

  5. Situation report: Heavy DDT contamination at Wheeler National Wildlife Refuge

    USGS Publications Warehouse

    Fleming, W.J.; Atkeson, T.Z.

    1980-01-01

    A DDT manufacturing plant that operated on the Redstone Arsenal near Huntsville, Alabama discharged DDT-Iaden effluent from 1947 to 1970 into a creek on Wheeler National Wildlife Refuge. Seven to 9 years after the plant closed, high DDT, DDE, and DDD levels were reported in soils, river sediments, and fish in the area. Eleven of 27 mallards (Anas platyrhynchos) collected on the Refuge during February 1979 had carcass DDE residues that exceeded levels associated with eggshell thinning. DDE residues in a smaller number of mallards exceeded levels associated with egg breakage, poor hatchability, and abnormal hehavior and poor survival of offspring. Several avian species have disappeared from the Refuge since 1950, probably due to both industrial discharges of DDT from the plant and insecticidal use of DDT in the area. The contamination still presents a threat to herons, waterfowl, and raptors including occasional wintering or migrant eagles (Haliaeetus leucocephalus), and probably many other avian species. A maternity colony of endangered gray bats (Myotis grisescens) is also threatened by this contamination.

  6. Adsorption of DDT and PCB by Nanomaterials from Residual Soil

    PubMed Central

    Taha, Mohd Raihan; Mobasser, Shariat

    2015-01-01

    This paper presents the findings of a study on adsorption of dichlorodiphenythreechloroethen (DDT) and polychlorinated biphenyls (PCBs) on three nanomaterials including Multi walled Carbon Nanotube (MWNT), nano-clay and nano-alumina. DDT and PCBs are of significant concern due their high toxicity and long environmental half-lives. Experiments were conducted using batch adsorption procedures at different DDT and PCBs concentrations, from 10 to 60 mg/L. The amounts of MWNT, nano-clay and Nano-alumina used were 0.25%, 0.50%, 0.75%, 1%, 2% and 10%. The adsorption of PCBs solution onto the MWNT, nano-clay and nano-alumina was characterized by an initial rapid adsorption which eventually became constant within 22, 20, and 17 hours, respectively. The adsorption of DDT solution onto the MWNT, nano-clay and nano-alumina was also characterized by an initial rapid adsorption which gradually became constant within 22, 22 and 16 hours, respectively. Results of this study indicated that MWNT was a better adsorbent material compared to nano-clay and nano-alumina for both contaminants in this study. While at 10% of MWNT 88.9% and 77% of DDT and PCB were removed by MWNT, respectively. The effect of pH and temperature were also investigated. PMID:26659225

  7. The effects of material properties and confinement on DDT

    SciTech Connect

    Lee, E.L.; Weston, A.M.; Aldis, D.F.

    1990-03-13

    We have used a DDT numerical code, RDUCT, to evaluate the effect of material properties and confinement on DDT in porous beds. RDUCT is a 1-D solid and gas two phase hydrodynamic program that computes deflagration to detonation transition in porous beds, using and ignition and growth'' type reaction model in a solid phase Lagrange coordinate system. The calculation model contains tamper masses at both ends of the reacting bed and is ignited by a squib at one end. Here RDUCT is used to compute the growth of reaction in porous bed inside a rigid tube. The input parameters are varied to produce changes in ignition, burn rate, and confinement. The results of this study illustrate the great sensitivity of the DDT phenomenon to these basic parameters. Implications to modelling and to practical problems of hazard are discussed. 15 refs., 19 figs., 2 tabs.

  8. Effects of DDT spray on eggs and nestlings of birds

    USGS Publications Warehouse

    Mitchell, R.T.

    1946-01-01

    Thirty-four nests of 11 species of birds containing eggs, and 38 nests of 12 species containing young of various ages, were used to determine the effect of applying DDT spray. Seventeen of the nests containing eggs and 19 of those containing young were left unsprayed as checks. The spray consisted of 1 pound of DDT to 2 pints of xylene diluted in fuel oil to make 1gallon, and was applied by a hand atomizer over an area of 1square foot surrounding and including each nest, at a dosage equivalent to 5 pounds of DDT per acre. This treatment evidently had no detrimental effect upon the hatching of eggs or development of young; it was not ohserved to cause abandonment of nests even when located in confined quarters.

  9. Surfactant enhanced electrokinetic remediation of DDT from soils.

    PubMed

    Karagunduz, Ahmet; Gezer, Aras; Karasuloglu, Gulden

    2007-10-15

    Electrokinetic remediation has been investigated extensively as one of the noble technologies in remediation of metal contaminated soils. However, its applications in remediation of organic contaminants have been limited due to low solubilities of organics in water. In addition, most organic contaminants are non-ionic and therefore, they are not mobile under electrical field. The use of surfactants may increase the remediation efficiency by increasing the solubility of organics. Significant fraction of organics associated with soil, can be transferred to micellar phase, which then can be transported toward either cathode or anode, depending on the ionic group of surfactants. In this study, the removal of hydrophobic organic contaminants from a soil using electrokinetic method was investigated in the presence of surfactants. A nonionic surfactant, Tween 80, and an anionic surfactant, SDBS, were used in the experiments. DDT was chosen as the model organic contaminant. Phase distribution studies and column experiments were conducted. It was found that both Tween 80 and SDBS had similar solubilization potentials for DDT. It was also shown that the aqueous DDT mass could reach from 0.01 to 13% of the total mass in the presence of 7500 mg/L of SDBS. No significant movement of DDT was observed when Tween 80 was used in the column experiments. This was attributed to low rates of electroosmotic flows and strong interaction of Tween 80 with the soil. The amount of surfactant was not enough to mobilize DDT significantly in the column studies. On the other hand, electrokinetic transport with SDBS yielded much better results. DDT transport toward the anode within the negatively charged micelles overcame the opposite electrosmotic flow. This was attributed to the lower degree of interaction between the soil and SDBS, and the electrokinetic transport of negatively charged micelles. PMID:17706747

  10. Effects of DDT on bobwhite quail adrenal gland

    USGS Publications Warehouse

    Lehman, J.W.; Peterle, T.J.; Mulls, C.M.

    1974-01-01

    A wide range of responses to sublethal levels of DDT exist, many of which are species specific and vary within each species depending upon age, sex, and physiological state. Sublethal levels of DDT do cause an increase in the adrenal cortical tissue of bobwhite quail, which may cause increased secretion of corticosteroids, and in turn affect reproduction. A delicate homeostatic balance exists within the avian endocrine system which may be disturbed by feeding sublethal levels of chlorinated hydrocarbon pesticides. This adverse effect on the endocrine system may cause subtle reproductive failures which go unnoticed until the population is greatly reduced.

  11. MASS BALANCE MODELING OF DDT DYNAMICS IN LAKES MICHIGAN AND SUPERIOR

    EPA Science Inventory

    A retrospective analysis of DDT dynamics subsequent to the imposition of a ban on DDT use in 1969 was conducted for Lakes Michigan and Superior. Trends in the available data indicate that DDT levels in both lakes declined at greater rates than were expected on the basis of hydrau...

  12. DDT and detonation waves in dust-air mixtures

    NASA Astrophysics Data System (ADS)

    Zhang, F.; Grönig, H.; van de Ven, A.

    This paper summarizes the studies of DDT and stable detonation waves in dust-air mixtures at the Stosswellenlabor of RWTH Aachen. The DDT process and propagation mechanism for stable heterogeneous dust detonations in air are essentially the same as in the oxygen environment studied previously. The dust DDT process in tubes is composed of a reaction compression stage followed by a reaction shock stage as the pre-detonation process. The transverse waves that couple the shock wave and the chemical energy release are responsible for the propagation of a stable dust-air detonation. However, the transverse wave spacing of dust-air mixtures is much larger. Therefore, DDT and propagation of a stable detonation in most industrial and agricultural, combustible dust-air mixtures require a tube that has a large diameter between 0.1 m and 1 m and a sufficient length-diameter ratio beyond 100, when an appropriately strong initiation energy is used. Two dust detonation tubes, 0.14 m and 0.3 m in diameter, were used for observation of the above-mentioned results in cornstarch, anthraquinone and aluminum dust suspended in air. Smoked-foil technique was also used to measure the cellular structure of dust detonations in the 0.3 m detonation tube.

  13. TOXICITY OF DDT FOOD AND WATER EXPOSURE TO FATHEAD MINNOWS

    EPA Science Inventory

    Fathead minnows (Pimephales promelas) were exposed during a partial chronic toxicity test to two DDT concentrations in the water, one in the diet, and combinations of water and diet for 266 days through a reproductive period of their life cycle. Tissue-residue analyses were perfo...

  14. 40 CFR 129.101 - DDT, DDD and DDE.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) Analytical method acceptable. Environmental Protection Agency method specified in 40 CFR part 136, except... acceptable. Environmental Protection Agency method specified in 40 CFR part 136, except that a 1-liter sample... 40 Protection of Environment 23 2012-07-01 2012-07-01 false DDT, DDD and DDE. 129.101 Section...

  15. 40 CFR 129.101 - DDT, DDD and DDE.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Analytical method acceptable. Environmental Protection Agency method specified in 40 CFR part 136, except... acceptable. Environmental Protection Agency method specified in 40 CFR part 136, except that a 1-liter sample... 40 Protection of Environment 21 2010-07-01 2010-07-01 false DDT, DDD and DDE. 129.101 Section...

  16. 40 CFR 129.101 - DDT, DDD and DDE.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) Analytical method acceptable. Environmental Protection Agency method specified in 40 CFR part 136, except... acceptable. Environmental Protection Agency method specified in 40 CFR part 136, except that a 1-liter sample... 40 Protection of Environment 22 2011-07-01 2011-07-01 false DDT, DDD and DDE. 129.101 Section...

  17. 40 CFR 129.101 - DDT, DDD and DDE.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) Analytical method acceptable. Environmental Protection Agency method specified in 40 CFR part 136, except... acceptable. Environmental Protection Agency method specified in 40 CFR part 136, except that a 1-liter sample... 40 Protection of Environment 23 2013-07-01 2013-07-01 false DDT, DDD and DDE. 129.101 Section...

  18. Inert plug formation in the DDT of granular energetic materials

    SciTech Connect

    Son, S.F.; Asay, B.W.; Bdzil, J.B.

    1996-05-01

    A mechanism is proposed to explain the {open_quotes}plugs{close_quotes} that have been observed in deflagration-to-detonation transition (DDT) of granular explosives. Numerical simulations are performed that demonstrate the proposed mechanism. Observed trends are reproduced. {copyright} {ital 1996 American Institute of Physics.}

  19. 40 CFR 129.101 - DDT, DDD and DDE.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) Analytical method acceptable. Environmental Protection Agency method specified in 40 CFR part 136, except... acceptable. Environmental Protection Agency method specified in 40 CFR part 136, except that a 1-liter sample... 40 Protection of Environment 22 2014-07-01 2013-07-01 true DDT, DDD and DDE. 129.101 Section...

  20. To Spray or Not To Spray? A Debate Over DDT.

    ERIC Educational Resources Information Center

    Dinan, Frank J.; Bieron, Joseph F.

    2001-01-01

    Presents an activity in which students grapple with the complex issues surrounding the use of DDT to control malaria which affects millions of people in developing nations. Considers risk/benefit analysis and the pre-cautionary principle, two techniques used when making policy decisions involving the impact of science and technology on society.…

  1. DDT and pyrethroid resistance in Anopheles arabiensis from South Africa

    PubMed Central

    2013-01-01

    Background Pyrethroid resistance has been well documented in Anopheles arabiensis, one of the major African malaria vectors, and the predominant malaria vector in South Africa. Methods In this study, the genetic basis of pyrethroid resistance in a selected laboratory strain of An. arabiensis from South Africa was investigated using a custom-made microarray, known as the An. gambiae detoxification chip. Results A large number of P450 genes were over-transcribed, as well as a suite of redox genes and glutathione S-transferases. The five genes that showed the highest level of gene transcription when compared with an insecticide susceptible strain were: CYP6AG2, CYPZ1, TPX2, CYPZ2 and CYP6P1. Conclusions Permethrin resistance in South African An. arabiensis is associated with increased transcription of multiple genes, and a large proportion of these genes were also previously recorded as over-transcribed in another An. arabiensis strain selected for resistance to DDT with cross-resistance to deltamethrin. The deltamethrin resistance developed de novo in the DDT-selected strain and is most likely due to increased transcription of those genes associated with DDT resistance. However, of particular interest was the fact that the strain selected for resistance to pyrethroids did not develop de novo resistance to DDT. These differences are compared and discussed. PMID:23924547

  2. Endocrine disruption mechanism of o,p'-DDT in mature male tilapia (Oreochromis niloticus)

    SciTech Connect

    Leanos-Castaneda, Olga . E-mail: olgalidia09@yahoo.com; Kraak, Glen van der; Rodriguez-Canul, Rossanna; Gold, G.

    2007-06-01

    The aim of the present study was to evaluate, in vivo, the potential of o,p'-DDT to disrupt the endocrine system of mature male tilapia. In particular, the possibility that o,p'-DDT effects were mediated directly via the estrogen receptor (ER). Compounds with known ability to bind to the ER were employed: estradiol to induce and tamoxifen to inhibit the estrogenic effects result of the activation of the ER. In addition, an aromatase inhibitor, 4-hydrxyandrostenedione (4-OHA), was used to assess the ability of o,p'-DDT to induce estrogenic effects in a surrounding of low estradiol concentration. The effects of estradiol and o,p'-DDT were studied alone or in the presence of tamoxifen or 4-OHA at the end of a 12-day period of exposure. The main endpoints measured were plasma alkaline-labile phosphorous (ALP; an indirect indicator of vitellogenin), estradiol, testosterone and o,p'-DDT. It was found that o,p'-DDT was able to induce the vitellogenesis (measured as plasma ALP increase) and decrease the circulating levels of estradiol and testosterone. Interestingly, o,p'-DDT kept this ability in whole fish with low concentrations of estradiol which would exclude endogenous estradiol as indirect mediator of the estrogenic effects induced by o,p'-DDT. In addition, the plasma concentration of o,p'-DDT, instead of that of estradiol, was closely related to the plasma ALP increase induced by o,p'-DDT. This indicates that o,p'-DDT could have directly activated the vitellogenesis. The antiestrogenic action of tamoxifen to inhibit the vitellogenesis and the decrease on plasma estradiol induced by o,p'-DDT indicates that o,p'-DDT can bind directly to the ER. In conclusion, this in vivo study shows that o,p'-DDT has the potential to disrupt the endocrine system and strongly supports that the estrogenic actions of o,p'-DDT involve binding to the ER.

  3. A study of the cardiac effects of DDT in laboratory animals*

    PubMed Central

    Jeyaratnam, J.; Forshaw, P. J.

    1974-01-01

    The claim that the hearts of animals chronically exposed to DDT are unduly sensitive to the cardiotoxic effects of vasopressin was reexamined. Rats and rabbits were fed a diet containing DDT for 8 months and were given weekly doses of vasopressin, which causes a temporary myocardial ischaemia. Electrocardiograms, recorded at 2-week intervals, showed no significant increase in the incidence of cardiac arrhythmias in the DDT-fed animals. Intravenous noradrenaline given at the end of the 8-month period did not produce a greater incidence of arrhythmias in the DDT-fed animals than in the controls. Isolated heart muscle preparations from the DDT-fed and control rats did not differ in their peak developed tensions and maximum rates of tension development. DDT, TDE, and DDE levels in heart muscle and fat were below detectable levels in the control rats, whereas in the DDT-fed rats they were at least 100 times those normally found in human tissues. PMID:4549502

  4. Wood mouse and box turtle populations in an area treated annually with DDT for five years

    USGS Publications Warehouse

    Stickel, L.F.

    1951-01-01

    A 117-acre area of dense woodland on the Patuxent Research Refuge received an aerial application of DDT in oil at the rate of 2 pounds per acre gnnually for five years. DDT reached ground level in a much smaller amount (thousandths to hundredths of a pound per acre). Treatment was made during the first week of June of each year from 1945 through 1949. Field studies of the wood mouse population in DDT and check areas showed no significant differences in the two areas before and after the 1949 DDT treatment. There was no significant difference between trapping samples taken in DDT and check areas in 1945 and those taken in 1949. Field studies of the box turtles in DDT and check areas in 1945 and 1949 showed no significant difference in population size. Growth of the four young turtles taken in the DDT area in both 1945 and 1949 appeared to be normal in comparison with growth of check area turtles.

  5. Dechlorination of DDT, DDD and DDE in soil (slurry) phase using magnesium/palladium system.

    PubMed

    Gautam, Sumit Kumar; Suresh, Sumathi

    2006-12-01

    Mg0/Pd4+ was able to dechlorinate >99% of extractable DDT (initial concentration of 10 mg DDT kg(-1) of soil) and >90% of extractable DDT (initial concentration of 50 mg DDT kg(-1) of soil) in soil slurry. Mg0/Pd4+ was also found to be effective in dechlorinating of 50 mg kg(-1) DDD and DDE, in soil aged for varying time periods. GC-MS analyses revealed the formation of 1,1-diphenylethane as an end product from DDT, DDE and DDD. To the best of our knowledge this is the first report describing the application Mg0/Pd4+ system for remediation of DDT, DDD and DDE contaminated soil. We conclude that reductive dechlorination reaction catalyzed by Mg0/Pd4+ may be a promising system to remediate soil contaminated with DDT and its dechlorinated products such as DDD and DDE. PMID:16996073

  6. Novel Chryseobacterium sp. PYR2 degrades various organochlorine pesticides (OCPs) and achieves enhancing removal and complete degradation of DDT in highly contaminated soil.

    PubMed

    Qu, Jie; Xu, Yang; Ai, Guo-Min; Liu, Ying; Liu, Zhi-Pei

    2015-09-15

    Long term residues of organochlorine pesticides (OCPs) in soils are of great concerning because they seriously threaten food security and human health. This article focuses on isolation of OCP-degrading strains and their performance in bioremediation of contaminated soil under ex situ conditions. A bacterium, Chryseobacterium sp. PYR2, capable of degrading various OCPs and utilizing them as a sole carbon and energy source for growth, was isolated from OCP-contaminated soil. In culture experiments, PYR2 degraded 80-98% of hexachlorocyclohexane (HCH) or 1,1,1-trichloro-2,2-bis (4-chlorophenyl) ethane (DDT) isomers (50 mg L(-1)) in 30 days. A pilot-scale ex situ bioremediation study of highly OCP-contaminated soil augmented with PYR2 was performed. During the 45-day experimental period, DDT concentration was reduced by 80.3% in PYR2-augmented soils (35.37 mg kg(-1) to 6.97 mg kg(-1)) but by only 57.6% in control soils. Seven DDT degradation intermediates (metabolites) were detected and identified in PYR2-augmented soils: five by GC/MS: 1,1-dichloro-2,2-bis (4-chlorophenyl) ethane (DDD), 1,1-dichloro-2,2-bis (4-chlorophenyl) ethylene (DDE), 1-chloro-2,2-bis (4-chlorophenyl) ethylene (DDMU), 1-chloro-2,2-bis (4-chlorophenyl) ethane (DDMS), and dichlorobenzophenone (DBP); and two by LC/MS: 4-chlorobenzoic acid (PCBA) and 4-chlorophenylacetic acid (PCPA). Levels of metabolites were fairly stable in control soils but varied greatly with time in PYR2-augmented soils. Levels of DDD, DDMU, and DDE in PYR2-augmented soils increased from day 0 to day 30 and then decreased by day 45. A DDT biodegradation pathway is proposed based on our identification of DDT metabolites in PYR2-augmented systems. PYR2 will be useful in future studies of OCP biodegradation and in bioremediation of OCP-contaminated soils. PMID:26203874

  7. Allinea DDT as a Parallel Debugging Alternative to Totalview

    SciTech Connect

    Antypas, K.B.

    2007-03-05

    Totalview, from the Etnus Corporation, is a sophisticated and feature rich software debugger for parallel applications. As Totalview has gained in popularity and market share its pricing model has increased to the point where it is often prohibitively expensive for massively parallel supercomputers. Additionally, many of Totalview's advanced features are not used by members of the scientific computing community. For these reasons, supercomputing centers have begun to search for a basic parallel debugging tool which can be used as an alternative to Totalview. As the cost and complexity of Totalview has increased over the years, scientific computing centers have started searching for a viable parallel debugging alternative. DDT (Distributed Debugging Tool) from Allinea Software is a relatively new parallel debugging tool which aims to provide much of the same functionality as Totalview. This review outlines the basic features and limitations of DDT to determine if it can be a reasonable substitute for Totalview. DDT was tested on the NERSC platforms Bassi, Seaborg, Jacquard and Davinci with Fortran90, C, and C++ codes using MPI and OpenMP for parallelism.

  8. High levels of DDT in breast milk: intake, risk, lactation duration, and involvement of gender.

    PubMed

    Bouwman, Hindrik; Kylin, Henrik; Sereda, Barbara; Bornman, Riana

    2012-11-01

    We investigated presence and levels of DDT in 163 breast milk samples from four South African villages where, in three of them, malaria is controlled with DDT-sprayed indoors. Mean ΣDDT levels in breast milk were 18, 11, and 9.5 mg/kg mf (milk fat) from the three DDT-sprayed villages, respectively, including the highest ΣDDT level ever reported for breast milk from South Africa (140 mg/kg mf). Understanding the causes for these differences would be informative for exposure reduction intervention. The Provisional Tolerable Daily Intake (PTDI) for DDT by infants, and the Maximum Residue Limit (MRL) were significantly exceeded. DDT had no effect on duration of lactation. There were indications (not significant) from DDT-sprayed villages that first-born female infants drink milk with more ΣDDT than first-born male infants, and vice versa for multipara male and female infants, suggesting gender involvement on levels of DDT in breast milk - requiring further investigation. PMID:22766005

  9. Enantiomeric fraction and isomeric composition to assess sources of DDT residues in soils.

    PubMed

    Bosch, Carme; Grimalt, Joan O; Fernández, Pilar

    2015-11-01

    Chiral pesticides such as o,p'-DDT can undergo enantioselective microbial degradation in soil. Hence, the enantiomeric fraction (EF) of o,p'-DDT was used as an approach to assess potential recent inputs of DDT in the lower part of the Ebro River basin (NE Spain), a region heavily impacted by agricultural and industrial activities, including a dicofol production and a chloro-alkali plants. The EFs of five out of nineteen soils were not different from the racemic value (0.505±0.010), confirming that the Ebro River and some of its tributaries, Segre and Cinca rivers, transported fresh DDT residues despite its ban in Spain during the 90 s. o,p'-DDT/p,p'-DDT ratios in soils suggest that recent use of technical DDT and/or DDT-contaminated dicofol may be responsible for the fresh DDT inputs in the Segre River, while in the Ebro River, they indicate a dominant contribution of technical DDT, likely related to the residues accumulated by the chloro-alkali plant discharges. PMID:26026902

  10. Matrix-enhanced degradation of p,p'-DDT during gas chromatographic analysis: A consideration

    USGS Publications Warehouse

    Foreman, W.T.; Gates, Paul M.

    1997-01-01

    Analysis of p,p‘-DDT in environmental samples requires monitoring the GC-derived breakdown of this insecticide, which produces p,p‘-DDD and/or p,p‘-DDE, both also primary environmental degradation products. A performance evaluation standard (PES) containing p,p‘-DDT but notp,p‘-DDD or p,p‘-DDE can be injected at regular intervals throughout an analytical sequence to monitor GC degradation. Some U.S. EPA methods limit GC breakdown of DDT in the PES to ≤20%. GC/MS analysis of large-volume natural water samples fortified with deuterium- and 13C-labeled p,p‘-DDT exhibited up to 65% DDT breakdown by the GC inlet. These matrix-enhanced GC degradation amounts substantially exceeded the <20% breakdown levels indicated by bracketing injections of the PES containing unlabeled and labeled DDT. Substantial matrix-enhanced GC degradation was not observed during analysis of a limited number of fractionated bed-sediment extracts containing labeled DDT. Use of isotopically labeled DDT seems to provide an effective tool for monitoring sample-specific DDT breakdown during GC/MS analysis. However, analyte co-elutions render impractical their use in GC/ECD analysis. The oc currence of matrix-enhanced GC degradation might have important implications on data quality and the resultant interpretations of the environmental degradation of DDT and other thermolabile contaminants.

  11. Melting glaciers: a probable source of DDT to the Antarctic marine ecosystem.

    PubMed

    Geisz, Heidi N; Dickhut, Rebecca M; Cochran, Michele A; Fraser, William R; Ducklow, Hugh W

    2008-06-01

    Persistent organic pollutants reach polar regions by long-range atmospheric transport and biomagnify through the food web accumulating in higher trophic level predators. We analyzed Adélie penguin (Pygoscelis adeliae) samples collected from 2004 to 2006 to evaluate current levels of sigmaDDT (p,p'-DDT + p,p'-DDE) in these birds, which are confined to Antarctica. Ratios of p,p'-DDT to p,p'-DDE in Adélie penguins have declined significantly since 1964 indicating current exposure to old rather than new sources of sigmaDDT. However, sigmaDDT has not declined in Adélie penguins from the Western Antarctic Peninsula for more than 30 years and the presence of p,p'-DDT in these birds indicates that there is a current source of DDT to the Antarctic marine food web. DDT has been banned or severely restricted since peak use in the 1970s, implicating glacier meltwater as a likely source for DDT contamination in coastal Antarctic seas. Our estimates indicate that 1-4 kg x y(-1) sigmaDDT are currently being released into coastal waters along the Western Antarctic Ice Sheet due to glacier ablation. PMID:18589951

  12. Persistent organic pollutants (PCB, DDT, HCH, HCB & BDE) in eels (Anguilla anguilla) in Scotland: current levels and temporal trends.

    PubMed

    Macgregor, Kenneth; Oliver, Ian W; Harris, Lynsay; Ridgway, Ian M

    2010-07-01

    Eels are an ideal biomonitor for persistent organic pollutants (POPs) because of their high lipid content, longevity and tendency to remain within a defined range during their freshwater life phase. This study investigated concentrations of POPs in eels (Anguilla anguilla) from 30 sites across Scotland, including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (BDEs), DDT (and metabolites), hexachlorocyclohexanes (alpha, beta, gamma-HCH), hexachlorobenzene (HCB), hexachlorobutadiene (HCBD) and pentachlorobenzene. Despite its EU-wide ban approximately 30 years ago, DDT and its derivatives were detected in almost all samples. PCB 153 and 138 were the most widely detected PCB congeners, while BDE 47 was the dominant BDE. Pentachlorobenzene was not detected, while HCBD was detected once only. alpha-HCH, beta-HCH and HCB concentrations were very low (generally <3 microg/kg or below detection). When compared with 1986 and 1995 data, the results revealed considerable decreases in p,p'-DDE concentrations. More drastic reductions were evident for gamma-HCH, reflecting the tightening restrictions on pesticide use imposed over the previous decades. PMID:20471146

  13. Selection of surfactant in remediation of DDT-contaminated soil by comparison of surfactant effectiveness.

    PubMed

    Guo, Ping; Chen, Weiwei; Li, Yueming; Chen, Tao; Li, Linhui; Wang, Guanzhu

    2014-01-01

    With an aim to select the most appropriate surfactant for remediation of DDT-contaminated soil, the performance of nonionic surfactants Tween80, TX-100, and Brij35 and one anionic surfactant sodium dodecyl benzene sulfonate (SDBS) in enhancement of DDT water solubility and desorption of DDT from contaminated soil and their adsorption onto soil and ecotoxicities were investigated in this study. Tween80 had the highest solubilizing and soil-washing ability for DDT among the four experimental surfactants. The adsorption loss of surfactants onto soil followed the order of TX-100 > Tween80 > Brij35 > SDBS. The ecotoxicity of Tween80 to ryegrass (Lolium perenne L.) was lowest. The overall performance considering about the above four aspects suggested that Tween80 should be selected for the remediation of DDT-contaminated soil, because Tween80 had the greatest solubilizing and soil-washing ability for DDT, less adsorption loss onto soil, and the lowest ecotoxicity in this experiment. PMID:23900948

  14. 2,2-bis(4-Chlorophenyl)acetic acid (DDA), a water-soluble urine biomarker of DDT metabolism in humans.

    PubMed

    Chen, Zhenshan; Maartens, Francois; Vega, Helen; Kunene, Simon; Gumede, Jonathan; Krieger, Robert I

    2009-01-01

    DDT metabolism in humans yields DDA as the principal urinary metabolite and potential exposure biomarker. A method for DDA analysis in human urine was developed using pentafluorobenzyl bromide and diisopropylethyl amine. Dried hexane extracts were reacted for 1 hour at room temperature. The stable DDA-pentafluorobenzyl-ester derivative was analyzed by gas chromatography-electron capture detector (GC-ECD) and confirmed by gas chromatography-mass spectrometry (GC-MS) in selective ion monitoring mode. The limit of detection for DDA was 0.1 microg/L urine by GC-ECD and 2 microg/L urine by GC-MS, with a relative standard deviation of 12%. Urine specimens from DDT applicators in Swaziland and South Africa were analyzed to evaluate the method. The mean DDA levels during the spray season and post season were 59 and 11 microg/L, respectively. These results must be interpreted cautiously because different groups of workers provided urine specimens in each case. The DDA urinalysis may be a feasible monitoring strategy for low-level occupational and residential DDT exposure assessment in antimalaria campaigns. PMID:19966144

  15. Volatile Metabolites

    PubMed Central

    Rowan, Daryl D.

    2011-01-01

    Volatile organic compounds (volatiles) comprise a chemically diverse class of low molecular weight organic compounds having an appreciable vapor pressure under ambient conditions. Volatiles produced by plants attract pollinators and seed dispersers, and provide defense against pests and pathogens. For insects, volatiles may act as pheromones directing social behavior or as cues for finding hosts or prey. For humans, volatiles are important as flavorants and as possible disease biomarkers. The marine environment is also a major source of halogenated and sulfur-containing volatiles which participate in the global cycling of these elements. While volatile analysis commonly measures a rather restricted set of analytes, the diverse and extreme physical properties of volatiles provide unique analytical challenges. Volatiles constitute only a small proportion of the total number of metabolites produced by living organisms, however, because of their roles as signaling molecules (semiochemicals) both within and between organisms, accurately measuring and determining the roles of these compounds is crucial to an integrated understanding of living systems. This review summarizes recent developments in volatile research from a metabolomics perspective with a focus on the role of recent technical innovation in developing new areas of volatile research and expanding the range of ecological interactions which may be mediated by volatile organic metabolites. PMID:24957243

  16. Global Status of DDT and Its Alternatives for Use in Vector Control to Prevent Disease

    PubMed Central

    van den Berg, Henk

    2009-01-01

    Objective I review the status of dichlorodiphenyltrichloroethane (DDT), used for disease vector control, along with current evidence on its benefits and risks in relation to the available alternatives. Data sources and extraction Contemporary data on DDT use were largely obtained from questionnaires and reports. I also conducted a Scopus search to retrieve published articles. Data synthesis DDT has been recommended as part of the arsenal of insecticides available for indoor residual spraying until suitable alternatives are available. Approximately 14 countries use DDT for disease control, and several countries are preparing to reintroduce DDT. The effectiveness of DDT depends on local settings and merits close consideration in relation to the alternatives. Concerns about the continued use of DDT are fueled by recent reports of high levels of human exposure associated with indoor spraying amid accumulating evidence on chronic health effects. There are signs that more malaria vectors are becoming resistant to the toxic action of DDT, and that resistance is spreading to new countries. A comprehensive cost assessment of DDT versus its alternatives that takes side effects into account is missing. Effective chemical methods are available as immediate alternatives to DDT, but the choice of insecticide class is limited, and in certain areas the development of resistance is undermining the efficacy of insecticidal tools. New insecticides are not expected in the short term. Nonchemical methods are potentially important, but their effectiveness at program level needs urgent study. Conclusions To reduce reliance on DDT, support is needed for integrated and multipartner strategies of vector control and for the continued development of new technologies. Integrated vector management provides a framework for developing and implementing effective technologies and strategies as sustainable alternatives to reliance on DDT. PMID:20049114

  17. Development of a Simple Dipstick Assay for Operational Monitoring of DDT

    PubMed Central

    Ismail, Hanafy M.; Kumar, Vijay; Singh, Rudra P.; Williams, Christopher; Shivam, Pushkar; Ghosh, Ayan; Deb, Rinki; Foster, Geraldine M.; Hemingway, Janet; Coleman, Michael; Coleman, Marlize; Das, Pradeep; Paine, Mark J. I.

    2016-01-01

    Background Indoor residual spraying (IRS) of DDT is used to control visceral leishmaniasis (VL) in India. However, the quality of spraying is severely compromised by a lack of affordable field assays to monitor target doses of insecticide. Our aim was to develop a simple DDT insecticide quantification kit (IQK) for monitoring DDT levels in an operational setting. Methodology/ principle findings DDT quantification was based on the stoichiometric release of chloride from DDT by alkaline hydrolysis and detection of the released ion using Quantab chloride detection strips. The assay was specific for insecticidal p,p`-DDT (LoQ = 0.082 g/m2). Bostik discs were effective in post spray wall sampling, extracting 25–70% of active ingredient depending on surface. Residual DDT was sampled from walls in Bihar state in India using Bostik adhesive discs and DDT concentrations (g p,p`-DDT/m2) were determined using IQK and HPLC (n = 1964 field samples). Analysis of 161 Bostik samples (pooled sample pairs) by IQK and HPLC produced excellent correlation (R2 = 0.96; Bland-Altman bias = −0.0038). IQK analysis of the remaining field samples matched HPLC data in identifying households that had been under sprayed, in range or over sprayed. Interpretation A simple dipstick assay has been developed for monitoring DDT spraying that gives comparable results to HPLC. By making laboratory-based analysis of DDT dosing accessible to field operatives, routine monitoring of DDT levels can be promoted in low- and middle- income countries to maximise the effectiveness of IRS. PMID:26760773

  18. Role of intestinal microflora in the degradation of DDT by rainbow trout (Salmo gairdneri)

    USGS Publications Warehouse

    Wedemeyer, Gary

    1968-01-01

    Though liver homogenates show apparent microsomal enzyme DDT-dehydrochlorinase activity, in the intact fish the intestinal microflora play a major role in DDT detoxication. Since the presence of this microflora in fish depends on the recent intake of food (12), the rate of detoxication and hence the toxicity of ingested DDT to the rainbow trout will probably depend somewhat on the available food supply.

  19. DDT (dicophane) and postmenopausal breast cancer in Europe: case-control study.

    PubMed Central

    van't Veer, P.; Lobbezoo, I. E.; Martín-Moreno, J. M.; Guallar, E.; Gómez-Aracena, J.; Kardinaal, A. F.; Kohlmeier, L.; Martin, B. C.; Strain, J. J.; Thamm, M.; van Zoonen, P.; Baumann, B. A.; Huttunen, J. K.; Kok, F. J.

    1997-01-01

    OBJECTIVE: To examine any possible links between exposure to DDE (1,1-dichloro-2,2-bis (p-chlorophenyl)ethylene), the persistent metabolite of the pesticide dicophane (DDT), and breast cancer. DESIGN: Multicentre study of exposure to DDE by measurement of adipose tissue aspirated from the buttocks. Laboratory measurements were conducted in a single laboratory. Additional data on risk factors for breast cancer were obtained by standard questionnaires. SETTING: Centres in Germany, the Netherlands, Northern Ireland, Switzerland, and Spain. SUBJECTS: 265 postmenopausal women with breast cancer and 341 controls matched for age and centre. MAIN OUTCOME MEASURE: Adipose DDE concentrations. RESULTS: Women with breast cancer had adipose DDE concentrations 9.2% lower than control women. No increased risk of breast cancer was found at higher concentrations. The odds ratio of breast cancer, adjusted for age and centre, for the highest versus the lowest fourth of DDE distribution was 0.73 (95% confidence interval 0.44 to 1.21) and decreased to 0.48 (0.25 to 0.95; P for trend = 0.02) after adjustment for body mass index, age at first birth, and current alcohol drinking. Adjustment for other risk factors did not materially affect these estimates. CONCLUSIONS: The lower DDE concentrations observed among the women with breast cancer may be secondary to disease inception. This study does not support the hypothesis that DDE increases risk of breast cancer in postmenopausal women in Europe. PMID:9240045

  20. Recent DDT and PCB contamination in the sediment and biota of the Como Bay (Lake Como, Italy).

    PubMed

    Bettinetti, R; Quadroni, S; Boggio, E; Galassi, S

    2016-01-15

    Due to its peculiar geographical and morphological characteristics, Lake Como (Northern Italy) represents an interesting study-case for investigating the sub-basin scale circulation of persistent organic pollutants (POPs) that, despite being banned since the 1970s, have reached surprisingly high concentrations in some southern alpine lakes as a consequence of their release from melting glaciers in recent years. In particular, the Como Bay, which is located in the city of Como, seems noteworthy because its waters have a longer residence time than the other areas of the lake. The analyses of the historical concentration of PCBs, pp′DDT and its metabolites in a sediment core sampled from the Como Bay covering a time-period from their ban to recent times, showed that the DDTs have never experienced a significant (p < 0.05) decrease over time, with concentrations of the most abundant homologue, pp′DDE, ranging from 27 to 75 ng g(-1) d.w. Conversely PCBs significantly (p < 0.05) decreased towards recent times, reaching concentrations around 80 ng g(-1) d.w. The contribution of high altitude and local sources was recorded also in the food web: both zooplankton and the zooplanktivorous fish agone were mainly contaminated by pp′DDE (81.4 ng g(-1) w.w. and 534.6 ng g(-1) w.w. respectively) and by the PCB metabolite hexa-CB (449.7 ng g(-1) w.w. and 1672.1 ng g(-1) w.w. respectively). The DDT concentrations in the agone (sampled during the years 2006–2009) never exceeded the limits for human consumption in Italy, while concentrations of six selected PCBs exceeded human health advisory recommendations in one of the fish samples analysed, when it was approximately two times higher than the recommended value of 125 ng g(-1) w.w. PMID:26520265

  1. Evaluation of biostimulation and Tween 80 addition for the bioremediation of long-term DDT-contaminated soil.

    PubMed

    Betancur-Corredor, Bibiana; Pino, Nancy J; Cardona, Santiago; Peñuela, Gustavo A

    2015-02-01

    The bioremediation of a long-term contaminated soil through biostimulation and surfactant addition was evaluated. The concentrations of 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) and its metabolites 1,1-dichloro-2,2-bis(4-chlorophenyl) ethane (DDD) and 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (DDE) were monitored during an 8-week remediation process. Physicochemical characterization of the treated soil was performed before and after the bioremediation process. The isolation and identification of predominant microorganisms during the remediation process were also carried out. The efficiency of detoxification was evaluated after each bioremediation protocol. Humidity and pH and the heterotrophic microorganism count were monitored weekly. The DDT concentration was reduced by 79% after 8 weeks via biostimulation with surfactant addition (B+S) and 94.3% via biostimulation alone (B). Likewise, the concentrations of the metabolites DDE and DDD were reduced to levels below the quantification limits. The microorganisms isolated during bioremediation were identified as Bacillus thuringiensis, Flavobacterium sp., Cuprivadius sp., Variovorax soli, Phenylobacterium sp. and Lysobacter sp., among others. Analysis with scanning electron microscopy (SEM) allowed visualization of the colonization patterns of soil particles. The toxicity of the soil before and after bioremediation was evaluated using Vibrio fischeri as a bioluminescent sensor. A decrease in the toxic potential of the soil was verified by the increase of the concentration/effect relationship EC50 to 26.9% and 27.2% for B+S and B, respectively, compared to 0.4% obtained for the soil before treatment and 2.5% by natural attenuation after 8 weeks of treatment. PMID:25662244

  2. Inheritance of DDT-resistance in a European strain of Blattella germanica (L.).

    PubMed

    COCHRAN, D G; ROSS, M H

    1962-01-01

    A strain of Blattella germanica has recently been obtained from Europe which has proved to be highly resistant to DDT. This paper reports on genetical studies designed to show the mechanism of inheritance of the trait. Various crosses involving this strain and strains susceptible to DDT or possessing genetic markers were made. Progeny were tested for resistance to DDT and were examined for markers. The results show that DDT resistance is inherited as a simple Mendelian trait, with the hybrid being incompletely susceptible. Resistance appears to be on the same linkage group as "balloon-wing", but is independent of "orange-body". PMID:14021877

  3. In Vitro Effects of the Endocrine Disruptor p,p’-DDT on Human Follitropin Receptor

    PubMed Central

    Munier, Mathilde; Grouleff, Julie; Gourdin, Louis; Fauchard, Mathilde; Chantreau, Vanessa; Henrion, Daniel; Coutant, Régis; Schiøtt, Birgit; Chabbert, Marie; Rodien, Patrice

    2016-01-01

    Background: 1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene (p,p′-DDT) is a persistent environmental endocrine disruptor (ED). Several studies have shown an association between p,p′-DDT exposure and reproductive abnormalities. Objectives: To investigate the putative effects of p,p′-DDT on the human follitropin receptor (FSHR) function. Methods and Results: We used Chinese hamster ovary (CHO) cells stably expressing human FSHR to investigate the impact of p,p′-DDT on FSHR activity and its interaction with the receptor. At a concentration of 5 μM p,p′-DDT increased the maximum response of the FSHR to follitropin by 32 ± 7.45%. However, 5 μM p,p′-DDT decreased the basal activity and did not influence the maximal response of the closely related LH/hCG receptor to human chorionic gonadotropin (hCG). The potentiating effect of p,p′-DDT was specific for the FSHR. Moreover, in cells that did not express FSHR, p,p′-DDT had no effect on cAMP response. Thus, the potentiating effect of p,p′-DDT was dependent on the FSHR. In addition, p,p′-DDT increased the sensitivity of FSHR to hCG and to a low molecular weight agonist of the FSHR, 3-((5methyl)-2-(4-benzyloxy-phenyl)-5-{[2-[3-ethoxy-4-methoxy-phenyl)-ethylcarbamoyl]-methyl}-4-oxo-thiazolidin-3-yl)-benzamide (16a). Basal activity in response to p,p′-DDT and potentiation of the FSHR response to FSH by p,p′-DDT varied among FSHR mutants with altered transmembrane domains (TMDs), consistent with an effect of p,p′-DDT via TMD binding. This finding was corroborated by the results of simultaneously docking p,p′-DDT and 16a into the FSHR transmembrane bundle. Conclusion: p,p′-DDT acted as a positive allosteric modulator of the FSHR in our experimental model. These findings suggest that G protein–coupled receptors are additional targets of endocrine disruptors. Citation: Munier M, Grouleff J, Gourdin L, Fauchard M, Chantreau V, Henrion D, Coutant R, Schiøtt B, Chabbert M, Rodien P. 2016

  4. DDT exposure of frogs: A case study from Limpopo Province, South Africa.

    PubMed

    Viljoen, Ignatius M; Bornman, Riana; Bouwman, Hindrik

    2016-09-01

    Amphibians are globally under pressure with environmental contaminants contributing to this. Despite caution aired more than 80 years ago of threats posed to amphibians by DDT spraying for disease vector control, no data have been published on concentrations or effects of DDT contamination in frogs from areas where DDT is actively sprayed to control the insect vectors of malaria. In this study, we sampled fat bodies of Xenopus laevis and Xenopus muelleri naturally occurring in an area where indoor residual spraying of DDT is employed and from adjacent, non-sprayed, areas. ΣDDT concentrations ranged between DDT in the eggs of the Grey Heron Ardea cinerea. This suggests that the DDT we found in frogs may have contributed to DDT loadings higher in the food web. These findings, combined with other studies from this area, support the need to reduce and eventually move away from DDT in malaria control safely and sustainably. PMID:27317939

  5. Glutathion S-transferase activity and DDT-susceptibility of Malaysian mosquitos.

    PubMed

    Lee, H L; Chong, W L

    1995-03-01

    Comparative DDT-susceptibility status and glutathion s-transferase (GST) activity of Malaysian Anopheles maculatus, Culex quinquefasciatus and Aedes aegypti was investigated to ascertain the role of this enzyme in DDT resistance. The standardised WHO dose-mortality bioassay tests were used to determine DDT susceptibility in these mosquitos, whilst GST microassay (Brogdon and Barber, 1990) was conducted to measure the activity of this enzyme in mosquito homogenate. It appeared that DDT susceptibility status of Malaysian mosquitos was not correlated with GST activity. PMID:8525405

  6. Wildlife effects of DDT dust used for tick control on a Texas prairie

    USGS Publications Warehouse

    George, J.L.; Stickel, W.H.

    1949-01-01

    SUMMARY The effect of DDT dust on wildlife was studied at Camp Bullis, Bexar County, Texas, in the summer of 1947. Studies were made on a 206.6 acre plot that was treated with DDT for experimental control of the Lone Star tick (Amblyomrna americanum). A dust consisting of one part of DDT to nine parts of pyrophyllite was applied at an average rate of 4.4 pounds of DDT per acre. The limits of DDT concentration that affected wildlife cannot be stated exactly because of a heavy rain that fell near the end of the dusting, and because of irregularity in DDT deposition. Since absolute uniformity of dusting could not be expected in any large scale DDT application, the effects observed in these trials were probably fairly representative. However, continued dry weather would have permitted longer exposure to DDT, possibly with more severe effects than those found in this study. The vegetation of the experimental area was roughly 70 percent ungrazed tall-grass prairie and 30 percent trees and shrubs. Ground and bush feeding birds were severely affected. Cardinals, lark sparrows, field sparrows, Bewick's wrens, Carolina wrens, Kentucky warblers, yellow-breasted chats, blue grosbeaks, and painted buntings were nearly or entirely eliminated from the treated area. Birds affected, but less drastically reduced in numbers, were yellow-billed cuckoo, black and white warbler, yellow-throated vireo, and white-eyed vireo. Birds found dead in the DDT area were 9 cardinals, 2 painted buntings, 2 lark sparrows, 1 yellow-breasted chat, and 1 white-eyed vireo. Bird mortality had begun by the day after dusting and was largely over by the end of the fifth day. Census of deer in DDT and check areas before and after treatment showed no reduction in deer numbers and no diminution in use of the DDT area. No deer or fawns were found dead or affected. Box-trapping of raccoons in DDT and check areas before and after treatment showed no effects that could be attributed to DDT. Limited observations on

  7. ATP-binding cassette transporter enhances tolerance to DDT in Tetrahymena.

    PubMed

    Ning, YingZhi; Dang, Huai; Liu, GuangLong; Xiong, Jie; Yuan, DongXia; Feng, LiFang; Miao, Wei

    2015-03-01

    The reuse of dichlorodiphenyltrichloroethane (DDT) as an indoor residual spray was permitted by the World Health Organization in 2007, and approximately 14 countries still use DDT to control disease vectors. The extensive exposure of insects to DDT has resulted in the emergence of DDT resistance, especially in mosquitoes, and the mechanism for this resistance in mosquitoes has been widely reported. Spraying can also introduce DDT directly into surface water, and DDT can subsequently accumulate in microorganisms, but the mechanism for the resistance to DDT degradation in microorganisms is unclear. Using whole-genome microarray analysis, we detected an abcb15 gene that was up-regulated in a specific manner by DDT treatment in T. thermophile. The deduced ABCB15 peptide sequence had two transmembrane domains (TMDs) and two nucleotide-binding domains (NBDs) to form the structure TMD-NBD-TMD-NBD, and each NBD contained three conserved motifs: Walker-A, C-loop, and Walker-B, which indicated the T. thermophila abcb15 was a typical ABC transporter gene. The expression of ABCB15 fused with a C-terminal green fluorescent protein was found to be on the periphery of the cell, suggesting that ABCB15 was a membrane pump protein. In addition, cells with abcb15 partially knocked down (abcb15-KD) grew slower than wild-type cells in the presence of 256 mg L(-1) DDT, indicating the tolerance of abcb15-KD strain to DDT exposure was decreased. Thus, we suggest that in Tetrahymena, the membrane pump protein encoded by ABCT gene abcb15 can enhance the tolerance to DDT and protect cells from this exogenous toxin by efficiently pumping it to the extracellular space. PMID:25260902

  8. Metabolic and Target-Site Mechanisms Combine to Confer Strong DDT Resistance in Anopheles gambiae

    PubMed Central

    Mitchell, Sara N.; Rigden, Daniel J.; Dowd, Andrew J.; Lu, Fang; Wilding, Craig S.; Weetman, David; Dadzie, Samuel; Jenkins, Adam M.; Regna, Kimberly; Boko, Pelagie; Djogbenou, Luc; Muskavitch, Marc A. T.; Ranson, Hilary; Paine, Mark J. I.; Mayans, Olga; Donnelly, Martin J.

    2014-01-01

    The development of resistance to insecticides has become a classic exemplar of evolution occurring within human time scales. In this study we demonstrate how resistance to DDT in the major African malaria vector Anopheles gambiae is a result of both target-site resistance mechanisms that have introgressed between incipient species (the M- and S-molecular forms) and allelic variants in a DDT-detoxifying enzyme. Sequencing of the detoxification enzyme, Gste2, from DDT resistant and susceptible strains of An. gambiae, revealed a non-synonymous polymorphism (I114T), proximal to the DDT binding domain, which segregated with strain phenotype. Recombinant protein expression and DDT metabolism analysis revealed that the proteins from the susceptible strain lost activity at higher DDT concentrations, characteristic of substrate inhibition. The effect of I114T on GSTE2 protein structure was explored through X-ray crystallography. The amino acid exchange in the DDT-resistant strain introduced a hydroxyl group nearby the hydrophobic DDT-binding region. The exchange does not result in structural alterations but is predicted to facilitate local dynamics and enzyme activity. Expression of both wild-type and 114T alleles the allele in Drosophila conferred an increase in DDT tolerance. The 114T mutation was significantly associated with DDT resistance in wild caught M-form populations and acts in concert with target-site mutations in the voltage gated sodium channel (Vgsc-1575Y and Vgsc-1014F) to confer extreme levels of DDT resistance in wild caught An. gambiae. PMID:24675797

  9. Assessment of DDT levels in selected environmental media and biological samples from Mexico and Central America.

    PubMed

    Pérez-Maldonado, Iván N; Trejo, Antonio; Ruepert, Clemens; Jovel, Reyna del Carmen; Méndez, Mónica Patricia; Ferrari, Mirtha; Saballos-Sobalvarro, Emilio; Alexander, Carlos; Yáñez-Estrada, Leticia; Lopez, Dania; Henao, Samuel; Pinto, Emilio R; Díaz-Barriga, Fernando

    2010-03-01

    Taking into account the environmental persistence and the toxicity of DDT, the Pan American Health Organization (PAHO) organized a surveillance program in Mesoamerica which included the detection of residual DDT in environmental (soil) and biological samples (fish tissue and children's blood). This program was carried out in communities from Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama. This paper presents the first report of that program. As expected, the results show that the levels for [summation operator] DDT in soil (outdoor or indoor) and fish samples in the majority of the locations studied are below guidelines. However, in some locations, we found children with high concentrations of DDT as in Mexico (mean level 50.2 ng/mL). Furthermore, in some communities and for some matrices, the DDT/DDE quotient is higher than one and this may reflect a recent DDT exposure. Therefore, more efforts are needed to avoid exposure and to prevent the reintroduction of DDT into the region. In this regard it is important to know that under the surveillance of PAHO and with the support of UNEP, a regional program in Mesoamerica for the collection and disposal of DDT and other POPs stockpiles is in progress. PMID:20092871

  10. ANAEROBIC DDT BIOTRANSFORMATION: ENHANCEMENT BY APPLICATION OF SURFACTANTS AND LOW OXIDATION REDUCTION POTENTIAL

    EPA Science Inventory

    Enhancement of anaerobic DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane) biotransformation by mixed cultures was studied with application of surfactants and oxidation reduction potential reducing agents. Without amendments, DDT transformation resulted mainly in the pr...

  11. Enantioselective Cytotoxicity Profile of o,p’-DDT in PC 12 Cells

    PubMed Central

    Zhang, Chunlong; Wen, Yuezhong; Liu, Weiping

    2012-01-01

    Background The continued uses of dichlordiphenyltrichloroethane (DDT) for indoor vector control in some developing countries have recently fueled intensive debates toward the global ban of this persistent legacy contaminant. Current approaches for ecological and health risk assessment has ignored the chiral nature of DDT. In this study by employing an array of cytotoxicity related endpoints, we investigated the enantioselective cytotoxicity of o,p’-DDT. Principal Findings we demonstrated for the first time that R-(−)-o,p’-DDT caused more neuron cell death by inducing more severe oxidative stress, which selectively imbalanced the transcription of stress-related genes (SOD1, SOD2, HSP70) and enzyme (superoxide dismutase and lactate dehydrogenase) activities, and greater cellular apoptosis compared to its enantiomer S-(+)-o,p’-DDT at the level comparable to malaria area exposure (parts per million). We further elucidated enantioselective modes of action using microarray combined with enzyme-linked immunosorbent assay. The enantioselective apoptosis might involve three signaling pathways via caspase 3, tumor protein 53 (p53) and NFkB. Conclusions Based on DDT stereochemistry and results reported for other chiral pesticides, our results pointed to the same directional enantioselectivity of chiral DDT toward mammalian cells. We proposed that risk assessment on DDT should consider the enantiomer ratio and enantioselectivities. PMID:22937105

  12. [Effect of Cd on remediation of DDT contaminated soil using different laccase forms].

    PubMed

    Zhao, Yue-chun; Fu, Rong; Mo, Ce-huiz; Yi, Xiao-yun

    2008-08-01

    This study investigated the effect of Cd on remediation of DDT contaminated soil using free laccase and immobilized reversed micelles laccase. The results show: degradation rates of ingredients of DDT and total DDT reduced with increasing of Cd concentration, the higher percentage of components in total DDT, the greater impact of Cd on them. Degradation rates of different components were p, p'-DDT > p, p'-DDD > o,p'-DDT > p, p'-DDE. When Cd concentration was 0, 0.5, 1 and 2 mg x kg(-1), the responding degradation rates of DDTs were measured at 50.68%, 32.50%, 14.92% and 13.40%, respectively. Compared with free laccase, degradation rate of total DDT by immobilized reversed micelles laccase nearly increased by 20% in soil without Cd and 30% in soil with 0.5 mg x kg(-1) Cd, implying that immobilized reversed micelles laccase is more effective for DDT degradation than free laccase. PMID:18839595

  13. Bioaugmentation of DDT-contaminated soil by dissemination of the catabolic plasmid pDOD.

    PubMed

    Gao, Chunming; Jin, Xiangxiang; Ren, Jingbei; Fang, Hua; Yu, Yunlong

    2015-01-01

    A plasmid transfer-mediated bioaugmentation method for the enhancement of dichlorodiphenyltrichloroethane (DDT) degradation in soil was developed using the catabolic plasmid pDOD from Sphingobacterium sp. D-6. The pDOD plasmid could be transferred to soil bacteria, such as members of Cellulomonas, to form DDT degraders and thus accelerate DDT degradation. The transfer efficiency of pDOD was affected by the donor, temperature, moisture, and soil type. Approximately 50.7% of the DDT in the contaminated field was removed 210 days after the application of Escherichia coli TG I (pDOD-gfp). The results suggested that seeding pDOD into soil is an effective bioaugmentation method for enhancing the degradation of DDT. PMID:25597661

  14. Dieldrin and DDT: accumulation from water and food by lake trout (Salvelinus namaycush) in the laboratory

    USGS Publications Warehouse

    Reinert, Robert E.; Stone, Linda J.; Bergman, Harold L.

    1974-01-01

    In the laboratory we measured the amounts of dieldrin and p,p'DDT accumulated by fish from contaminated water and food to determine how fish from Lake Michigan accumulate high concentrations of these insecticides from an environment where the concentrations in water are generally less than 0.01 ppb. Eight groups of yearling lake trout (Salvelinus namaycush) were exposed to different combinations of dieldrin and p,p'DDT in water and food. Concentrations of dieldrin and p,p'DDT ranged from 0.006 to 0.010 ppb in water and from 1,700 to 2,300 ppb in food (Oregon moist pellets). After 152 days of exposure to insecticides in water, fish had accumulated an average of 478 ppb dieldrin or 352 ppb p,p'DDT. Fish exposed to dieldrin and p,p'DDT in food accumulated 470 and 648 ppb, respectively. However, it was difficult to determine exactly how much of either insecticide was accumulated from the food because trace amounts (0.003-0.004 ppb) had leached from food or feces. After exposure to the insecticide was terminated, fish eliminated dieldrin at a much faster rate than p,p'DDT. In fish exposed to a combination of dieldrin and p,p'DDT in water and then held for 125 days in uncontaminated water, the total amount of dieldrin (I?g) declined 89%, but the total amount of p,p'DDT remained unchanged. We used data from this study to estimate how much p,p'DDT adult Lake Michigan coho salmon (Oncorhynchus kisutch) accumulated from water and from food during a 104-day period (May-August 1968). The estimates suggest that during these months coho salmon accumulated most of the body burden of p,p'DDT from food.

  15. Co-metabolism of DDT by the newly isolated bacterium, Pseudoxanthomonas sp. wax

    PubMed Central

    Wang, Guangli; Zhang, Ji; Wang, Li; Liang, Bin; Chen, Kai; Li, Shunpeng; Jiang, Jiandong

    2010-01-01

    Microbial degradation of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) is the most promising way to clean up DDT residues found in the environment. In this paper, a bacterium designated as wax, which was capable of co-metabolizing DDT with other carbon sources, was isolated from a long-term DDT-contaminated soil sample by an enrichment culture technique. The new isolate was identified as a member of the Pseudoxanthomonas sp., based on its morphological, physiological and biochemical properties, as well as by 16S rRNA gene analysis. In the presence of 100 mg l-1 glucose, the wax strain could degrade over 95% of the total DDT, at a concentration of 20 mg l-1, in 72 hours, and could degrade over 60% of the total DDT, at a concentration of 100 mg l-1, in 144 hours. The wax strain had the highest degradation efficiency among all of the documented DDT-degrading bacteria. The wax strain could efficiently degrade DDT at temperatures ranging from 20 to 37°C, and with initial pH values ranging from 7 to 9. The bacterium could also simultaneously co-metabolize 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), 2,2-bis(p-chlorophenyl)-1,1-dichlorethylene (DDE), and other organochlorine compounds. The wax strain could also completely remove 20 mg kg-1 of DDT from both sterile and non-sterile soils in 20 days. This study demonstrates the significant potential use of Pseudoxanthomonas sp. wax for the bioremediation of DDT in the environment. PMID:24031514

  16. Effects of DDT on bird population of scrub forest

    USGS Publications Warehouse

    Robbins, C.S.; Stewart, R.E.

    1949-01-01

    An oil spray of DDT was applied at the rate of five pounds per acre to a 90-acre tract of 5-year-old scrub and sapling growth at Beltsville, Maryland. Bird population studies were carried on in a 30-acre plot at the center of the sprayed area, and in a 30-acre check area of the same habitat one-half mile away. Of the five commonest species in the sprayed area, the Maryland yellowthroat, prairie warbler, and house wren were reduced 80 per cent, and the red-eyed towhee was apparently reduced 35 per cent; while no appreciable change in the numbers of yellow-breasted chats was noted. The total decrease for the five commonest species, which represented 77 per cent of the original population, was 65 per cent.

  17. Splice form variant and amino acid changes in MDR49 confers DDT resistance in transgenic Drosophila.

    PubMed

    Seong, Keon Mook; Sun, Weilin; Clark, John M; Pittendrigh, Barry R

    2016-01-01

    The ATP-binding cassette (ABC) transporters represent a superfamily of proteins that have important physiological roles in both prokaryotes and eukaryotes. In insects, ABC transporters have previously been implicated in insecticide resistance. The 91-R strain of Drosophila melanogaster has been intensely selected with DDT over six decades. A recent selective sweeps analysis of 91-R implicated the potential role of MDR49, an ABC transporter, in DDT resistance, however, to date the details of how MDR49 may play a role in resistance have not been elucidated. In this study, we investigated the impact of structural changes and an alternative splicing event in MDR49 on DDT-resistance in 91-R, as compared to the DDT susceptible strain 91-C. We observed three amino acid differences in MDR49 when 91-R was compared with 91-C, and only one isoform (MDR49B) was implicated in DDT resistance. A transgenic Drosophila strain containing the 91-R-MDR49B isoform had a significantly higher LD50 value as compared to the 91-C-MDR49B isoform at the early time points (6 h to 12 h) during DDT exposure. Our data support the hypothesis that the MDR49B isoform, with three amino acid mutations, plays a role in the early aspects of DDT resistance in 91-R. PMID:27003579

  18. Enhanced degradation performances of plate-like micro/nanostructured zero valent iron to DDT.

    PubMed

    Kang, Shenghong; Liu, Shengwen; Wang, Huimin; Cai, Weiping

    2016-04-15

    Micro/nanostructured zero valent iron (MNZVI) is successfully mass-synthesized by ball-milling the industrially-reduced iron powders. The as-prepared MNZVI is plate-like in morphology with about 2-5μm in planar size and 35-55nm in thickness, and ∼16m(2)/g in specific surface area. Such plate-like MNZVI has demonstrated much higher degradation performances to DDT [or 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane] in the aqueous solution than the commercial ZVI powders under acidic conditions. The MNZVI-induced DDT degradation is also much faster than the previously reported results. The time-dependent DDT removal amount can be described by the pseudo first-order kinetic model. Further experiments have shown that more than 50% of DDT can be mineralized in 20min and the rest is dechlorinated to DDX (the products with less chlorine). It has been revealed that the DDT degradation could be attributed to the acid assisted ZVI-induced mineralization and dechlorination. The mineralization process is dominant during the initial stage within 20min, and the dechlorination is the main reaction in the anaphase of the degradation. This work not only deepens understanding of DDT degradation but also could provide a highly efficient material for the practical treatment of the DDT in a real environment. PMID:26780701

  19. Comparison study of the sensitivities of some indices of DDT exposure in human blood and urine

    SciTech Connect

    Nhachi, C.F.B.; Loewenson, R. )

    1989-10-01

    Although exposure to DDT (2,2-bis(p-chlorophenyl1)1,1,1,-trichloroethane) is not normally associated with fatality or chronic adverse effects to human life, it is a known hazard to the ecosystem. Blood levels of DDT and some of its derivatives have been used to assess extent of exposure or the body load of DDT in humans. In experimental studies, ingestion of DDT has been associated with reduced liver stores of vitamin A, and increased serum levels of vitamin A. The same study also revealed a significant correlation of vitamin A and DDE serum levels. Generally an increase in excreted 17-B-hydroxycortisone has been associated with DDT exposure. Increased excretion of 6-B-hydroxycortisol has been noted in workers who were involved in the formulation of DDT. The objective of this study was to compare the sensitivities of some indices of DDT exposure in humans. The indices which were compared are serum vitamin A and DDE levels and urinary 17-B-hydroxycortisol.

  20. Using Information on Uncertainty to Improve Environmental Fate Modeling: A Case Study on DDT

    SciTech Connect

    Schenker, Urs; Scheringer, Martin; Sohn, Michael D.; Maddalena, Randy L.; McKone, Thomas E.; Hungerbuhler, Konrad

    2008-10-01

    Present and future concentrations of DDT in the environment are calculated with the global multi-media model CliMoChem. Monte Carlo simulations are used to assess the importance of uncertainties in substance property data, emission rates, and environmental parameters for model results. Uncertainties in the model results, expressed as 95percent confidence intervals of DDT concentrations in various environmental media, in different geographical locations, and at different points in time are typically between one and two orders of magnitude. An analysis of rank correlations between model inputs and predicted DDT concentrations indicates that emission estimates and degradation rate constants, in particular in the atmosphere, are the most influential model inputs. For DDT levels in the Arctic, temperature dependencies of substance properties are also influential parameters. A Bayesian Monte Carlo approach is used to update uncertain model inputs based on measurements of DDT in the field. The updating procedure suggests a lower value for half-life in air and a reduced range of uncertainty for KOW of DDT. As could be expected, the Bayesian updating yields model results that are closer to observations, and model uncertainties have decreased. The combined sensitivity analysis and Bayesian Monte Carlo approach provide new insight into important processes that govern the global fate and persistence of DDT in the environment.

  1. Selective and conventional house-spraying of DDT and bendiocarb against Anopheles pseudopunctipennis in southern Mexico.

    PubMed

    Casas, M; Torres, J L; Bown, D N; Rodríguez, M H; Arredondo-Jiménez, J I

    1998-12-01

    Indoor feeding behaviors and mortalities of Anopheles pseudopunctipennis females were evaluated following contact with selective (bands covering mosquitoes' preferred resting areas) and full applications of DDT and bendiocarb on indoor sprayable surfaces. The DDT residues provoked strong avoidance behavior. To a lesser degree, mosquitoes were also repelled by bendiocarb-sprayed surfaces. Because of strong irritancy/repellency, unfed mosquitoes were driven outdoors in proportionally higher numbers. The resting time on selectively or fully DDT-sprayed huts was greatly reduced in comparison to bendiocarb-sprayed huts. Although unfed mosquitoes tended to rest on non-DDT-sprayed surfaces in the selectively treated hut, the man-biting rate was similar with both types of treatments. Unfed mosquitoes were repelled less from selectively bendiocarb-treated surfaces. Similar reductions in postfed resting times were observed on all surfaces suggesting that once fed, mosquitoes rested on sprayed surfaces for shorter intervals of time. Engorged mosquitoes had normal resting behavior (pre- and postspray) within the range of preferred resting heights in both DDT- and bendiocarb-sprayed huts, but the proportion of mosquitoes fed in the DDT-treated huts was lower. Selective spraying of walls was as effective as spraying the complete walls with both insecticides, but DDT was more effective in reducing mosquito-human contact. These studies show that by more effectively targeting vector behavior, a cost-effective alternative to traditional control techniques can be achieved. PMID:10084135

  2. Splice form variant and amino acid changes in MDR49 confers DDT resistance in transgenic Drosophila

    PubMed Central

    Seong, Keon Mook; Sun, Weilin; Clark, John M.; Pittendrigh, Barry R.

    2016-01-01

    The ATP-binding cassette (ABC) transporters represent a superfamily of proteins that have important physiological roles in both prokaryotes and eukaryotes. In insects, ABC transporters have previously been implicated in insecticide resistance. The 91-R strain of Drosophila melanogaster has been intensely selected with DDT over six decades. A recent selective sweeps analysis of 91-R implicated the potential role of MDR49, an ABC transporter, in DDT resistance, however, to date the details of how MDR49 may play a role in resistance have not been elucidated. In this study, we investigated the impact of structural changes and an alternative splicing event in MDR49 on DDT-resistance in 91-R, as compared to the DDT susceptible strain 91-C. We observed three amino acid differences in MDR49 when 91-R was compared with 91-C, and only one isoform (MDR49B) was implicated in DDT resistance. A transgenic Drosophila strain containing the 91-R-MDR49B isoform had a significantly higher LD50 value as compared to the 91-C-MDR49B isoform at the early time points (6 h to 12 h) during DDT exposure. Our data support the hypothesis that the MDR49B isoform, with three amino acid mutations, plays a role in the early aspects of DDT resistance in 91-R. PMID:27003579

  3. Cyclodiene insecticide, DDE, DDT, arsenic, and mercury contamination of big brown bats (Eptesicus fuscus) foraging at a Colorado Superfund site

    USGS Publications Warehouse

    O'Shea, T.J.; Everette, A.L.; Ellison, L.E.

    2001-01-01

    Rocky Mountain Arsenal (RMA) National Wildlife Area, near Denver, Colorado, is a Superfund site contaminated by past military and industrial uses, including pesticide manufacturing. From an ecosystem standpoint, the most critical contaminants at RMA are certain cyclodiene insecticides and metabolites, p,p???-DDE, p,p???-DDT, arsenic, and mercury. Bats are important ecosystem components that can be impacted by persistent contaminants because of their position in the food chain and their potential longevity and thus duration of exposure. Big brown bats (Eptesicus fuscus) were captured (n = 51) while foraging at RMA in the summers of 1997 and 1998 for determination of concentrations of contaminants of concern in carcasses, brains, and stomach contents. Adult females (n = 15) were also tracked by radiotelemetry to determine locations of nearest maternity roosts for sampling of guano for contaminant analysis and inspection for potential contaminant-induced mortality. Bats captured while foraging at RMA had measurable quantities of dieldrin and DDE in masticated insect samples from stomach contents and significantly higher concentrations of dieldrin, DDE, DDT, and mercury (juveniles) in carcasses than big brown bats (n = 26) sampled at a reference area 80 km to the north. Concentrations of dieldrin and DDE in brains of bats captured while foraging at RMA were also greater than in bats from the reference area, but not high enough to suggest mortality. Maximum concentrations of DDE, DDT, and cyclodienes in brains of big brown bats were found in adult males from RMA. Guano from the two closest known roosts had significantly higher concentrations of dieldrin, DDE, and mercury than guano from two roosts at the reference area. Dieldrin concentrations in carcasses of bats from RMA were highest in juveniles, followed by adult males and adult females. DDE concentrations in carcasses were lowest in adult females at both sites and highest in adult males at RMA. No contaminant

  4. Sediment analysis to support the recent glacial origin of DDT pollution in Lake Iseo (Northern Italy).

    PubMed

    Bettinetti, Roberta; Galassi, Silvana; Guilizzoni, Piero; Quadroni, Silvia

    2011-09-01

    In the present study, a depth-related distribution of Persistent Organic Pollutants (POPs) in sediments of Lake Iseo, one of the major southern Alpine Italian lakes, is reported in order to further test the hypothesis of melting Alpine glaciers as a secondary source of contamination. In a previous paper, a "glacier contamination hypothesis" was suggested to explain the unexpected contamination of the biota of Lake Iseo, mainly fed by the Alpine melting ice. The sediment core analyses covered around the last 50 years. The organic matter profile evaluated as a Loss-On-Ignition percentage indicated transition of the basin from an oligotrophic to a mesotrophic status at around the early 1970s, but there was no evidence of the shift to eutrophy in the 1980s. Among DDTs, pp'DDE was the predominant metabolite, accounting on average for 79.4% of the total DDT concentrations and ranging from 6.4 to 447.5 ng g(-1)d.w. PCBs ranged from 5.0 to 163.7 ng g(-1)d.w. The maximum PCB concentrations were found in sediment layers corresponding to the 1970s when the highest production and use of these compounds occurred in Italy. In contrast, concentrations of DDTs showed a sharp increase from the early 1990s, long after their agricultural use was banned in Italy. This delayed pollution provides support for the hypothesis that the recent retreat of glaciers represents a secondary pollution source for old pesticides that were stored in the ice at the time of their use in agriculture. PMID:21724223

  5. DDT-based indoor residual spraying suboptimal for visceral leishmaniasis elimination in India

    PubMed Central

    Coleman, Michael; Foster, Geraldine M.; Deb, Rinki; Pratap Singh, Rudra; Ismail, Hanafy M.; Shivam, Pushkar; Ghosh, Ayan Kumar; Dunkley, Sophie; Kumar, Vijay; Coleman, Marlize; Hemingway, Janet; Paine, Mark J. I.; Das, Pradeep

    2015-01-01

    Indoor residual spraying (IRS) is used to control visceral leishmaniasis (VL) in India, but it is poorly quality assured. Quality assurance was performed in eight VL endemic districts in Bihar State, India, in 2014. Residual dichlorodiphenyltrichloroethane (DDT) was sampled from walls using Bostik tape discs, and DDT concentrations [grams of active ingredient per square meter (g ai/m2)] were determined using HPLC. Pre-IRS surveys were performed in three districts, and post-IRS surveys were performed in eight districts. A 20% threshold above and below the target spray of 1.0 g ai/m2 was defined as “in range.” The entomological assessments were made in four districts in IRS and non-IRS villages. Vector densities were measured: pre-IRS and 1 and 3 mo post-IRS. Insecticide susceptibility to 4% DDT and 0.05% deltamethrin WHO-impregnated papers was determined with wild-caught sand flies. The majority (329 of 360, 91.3%) of pre-IRS samples had residual DDT concentrations of <0.1 g ai/m2. The mean residual concentration of DDT post-IRS was 0.37 g ai/m2; 84.9% of walls were undersprayed, 7.4% were sprayed in range, and 7.6% were oversprayed. The abundance of sand flies in IRS and non-IRS villages was significantly different at 1 mo post-IRS only. Sand flies were highly resistant to DDT but susceptible to deltamethrin. The Stockholm Convention, ratified by India in 2006, calls for the complete phasing out of DDT as soon as practical, with limited use in the interim where no viable IRS alternatives exist. Given the poor quality of the DDT-based IRS, ready availability of pyrethroids, and susceptibility profile of Indian sand flies, the continued use of DDT in this IRS program is questionable. PMID:26124110

  6. Prenatal DDT and DDE exposure and child IQ in the CHAMACOS cohort.

    PubMed

    Gaspar, Fraser W; Harley, Kim G; Kogut, Katherine; Chevrier, Jonathan; Mora, Ana Maria; Sjödin, Andreas; Eskenazi, Brenda

    2015-12-01

    Although banned in most countries, dichlorodiphenyl-trichloroethane (DDT) continues to be used for vector control in some malaria endemic areas. Previous findings from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) cohort study found increased prenatal levels of DDT and its breakdown product dichlorodiphenyl-dichloroethylene (DDE) to be associated with altered neurodevelopment in children at 1 and 2years of age. In this study, we combined the measured maternal DDT/E concentrations during pregnancy obtained for the prospective birth cohort with predicted prenatal DDT and DDE levels estimated for a retrospective birth cohort. Using generalized estimating equation (GEE) and linear regression models, we evaluated the relationship of prenatal maternal DDT and DDE serum concentrations with children's cognition at ages 7 and 10.5years as assessed using the Full Scale Intelligence Quotient (IQ) and 4 subtest scores (Working Memory, Perceptual Reasoning, Verbal Comprehension, and Processing Speed) of the Wechsler Intelligence Scale for Children (WISC). In GEE analyses incorporating both age 7 and 10.5 scores (n=619), we found prenatal DDT and DDE levels were not associated with Full Scale IQ or any of the WISC subscales (p-value>0.05). In linear regression analyses assessing each time point separately, prenatal DDT levels were inversely associated with Processing Speed at age 7years (n=316), but prenatal DDT and DDE levels were not associated with Full Scale IQ or any of the WISC subscales at age 10.5years (n=595). We found evidence for effect modification by sex. In girls, but not boys, prenatal DDE levels were inversely associated with Full Scale IQ and Processing Speed at age 7years. We conclude that prenatal DDT levels may be associated with delayed Processing Speed in children at age 7years and the relationship between prenatal DDE levels and children's cognitive development may be modified by sex, with girls being more adversely

  7. Prenatal and Postnatal Exposure to DDT by Breast Milk Analysis in Canary Islands

    PubMed Central

    Vall, Oriol; Gomez-Culebras, Mario; Puig, Carme; Rodriguez-Carrasco, Ernesto; Gomez Baltazar, Arelis; Canchucaja, Lizzeth; Joya, Xavier; Garcia-Algar, Oscar

    2014-01-01

    Introduction The use of p,p′-dichlorodiphenyltrichloroethane (DDT) has been banned since the late 1970s due to its toxicity. However, its long half-life makes it persistent in the environment and, consequently, almost everyone has DDT residues in the body. Human milk constitutes an ideal non-conventional matrix to investigate environmental chronic exposure to organochlorine compounds (OCs) residues. The study aimed to identify potential population risk factors of exposure to DDT due to the proximity to countries where it is still used. Methods Seventy-two consecutive lactating women were prospectively included in Tenerife, Canary Islands (Spain). A validated questionnaire was used to obtain socioeconomic, demographics data, and daily habits during pregnancy. DDT levels in breast milk were measured by gas chromatography with-electron capture detector (GC-ECD). Anthropometrics measurements in newborns were obtained. Results Thirty-four out of 72 (47.2%) of the analysed milk samples presented detectable levels of DDT (mean: 0.92 ng/g), ranging between 0.08 to 16.96 ng/g. The socio-demographic variables did not significantly differ between detectable DDT and non-detectable DDT groups. We found positive association between DDT levels and vegetables (OR (95%CI): 1.23 (1.01–1.50)) and poultry meat (OR (95%CI): 2.05 (1.16–3.60)) consumption, and also between the presence of DDT in breast milk and gestational age (OR (95%CI): 0.59 (0.40–0.90)). Conclusions DDT is present in breast milk of women at the time of delivery. Residual levels and the spread from countries still using DDT explain DDT detection from vegetables and from animal origin food. The presence of this compound in breast milk represents a pre- and postnatal exposure hazard for foetuses and infants due to chronic bioaccumulation and poor elimination, with possible deleterious effects on health. This data should be used to raise awareness of the risks of OCs exposure and to help establish health policies

  8. Inadvertent exposure to organochlorine pesticides DDT and derivatives in people from the Canary Islands (Spain).

    PubMed

    Zumbado, Manuel; Goethals, Muriel; Alvarez-León, Eva E; Luzardo, Octavio P; Cabrera, Félix; Serra-Majem, Lluis; Domínguez-Boada, Luis

    2005-03-01

    In 1998, one of the largest determinations of organochlorine pesticides in a representative sample of a Spanish population (682 serum samples from the Canary Islands) was made in the context of the "Canary Islands Nutrition Survey" (ENCA). In the Canary Islands, extensive farming areas have been developed in these last decades, with greenhouses dedicated to intensive cultivation using DDT in huge amounts. In Spain, similarly to other European countries, DDT was banned in the late 1970s. The pesticide residues in human serum are indicative of past and present exposure to them. Our objective is to point out the differences of pesticide contamination between islands; and together with this, if a connection could be established with gender, age, or habitat of subjects. Concentration of selected persistent organochlorine pollutants (p,p'-DDT, o,p'-DDT, p,p'-DDE, o,p'-DDE, p,p'-DDD, and o,p'-DDD) was measured with gas chromatography-electron capture detector. Almost all of the samples (99.3%) presented detectable levels of some DDT-derivatives, being p,p'-DDE the most frequently detected organochlorine. The median concentration of total DDT body burden, expressed in ng/g fat, present in the Canary Islands (370 ng/g fat) was similar to that found in other European countries, although it was noteworthy that a fourth of the population showed a total DDT body burden higher than 715 ng/g. Interestingly, statistical significant differences were found in serum levels of organochlorine pesticides between islands, being these levels higher in people from Tenerife and Gran Canaria (415 and 612 ng/g fat, respectively), the islands that present both highest population and highest surface devoted to intensive agriculture. As expected, serum levels of both total DDT body burden and p,p'-DDE increased with age. Statistically significant differences were also found in relation to gender, women showing higher levels of these organochlorine pesticides than men. One of the most relevant

  9. Evaluation of the potential carcinogenicity of DDT (50-29-3). Final report

    SciTech Connect

    Not Available

    1988-06-01

    DDT is a probable human carcinogen, classified as weight-of-evidence Group B2 under the EPA Guidelines for Carcinogen Risk Assessment. Evidence on potential carcinogenicity from animal studies is Sufficient. and the evidence from human studies is Inadequate. The potency factor (F) for DDT is estimated to be 5.58 (mg/kg/day)(-1), placing it in potency group 2 according to the CAG's methodology for evaluating potential carcinogens. Combining the weight-of-evidence group and the potency group, DDT is assigned a MEDIUM hazard ranking.

  10. FISH TISSUE RESIDUE-BASED WILDLIFE VALUES FOR PISCIVOUOUS WILDLIFE: CHLORDANE, DDT, DIELDRIN, HEXACHLOROBENZENE

    EPA Science Inventory

    Fish tissue residue-based wildlife values were derived for chlordane, DDT, dieldrin, endrin, hexachlorobenzene, mercury and PCBs. Piscivorous wildlife for which these benchmarks were derived include belted kingfisher, river otter and mink. Toxic endpoint selection, criteria for t...

  11. PHOTOCHEMICAL TRANSFORMATION OF THE DDT AND METHOXYCHLOR DEGRADATION PRODUCTS, DDE AND DMDE, BY SUNLIGHT

    EPA Science Inventory

    DDE and DMDE, degradation products of the pesticides DDT and methoxychlor, rapidly undergo an unusual photoisomerization in solution when exposed to sunlight. The isomerization involves the exchange of a vinyl chlorine and an ortho aromatic hydrogen. Other photoproducts identifie...

  12. Increased contraction frequency in rat uterine strips treated in vitro with o,p prime -DDT

    SciTech Connect

    Juberg, D.R.; Loch-Caruso, R. )

    1991-05-01

    Elevated levels of DDT and other organochlorine pesticides have been associated with spontaneous abortion and preterm birth in several species, including humans. Despite the prevalence of organochlorine pesticides in the environment, a mechanistic basis for this association has not been explored. Furthermore, while DDT has been associated with inhibition of calcium ATPases, altered gap junctional communication and electrophysiological changes, all of which could affect the excitation-contraction process characteristic of smooth muscle, direct effects of DDT on uterine smooth muscle have not been reported. This study was initiated to assess the direct effects of o,p{prime}-DDT (an estrogenic isomer present in the technical grade preparation) on pregnant rat uterine tissue.

  13. DDT vs. wildlife: Relationships between quantities ingested, toxic effects and tissue storage

    USGS Publications Warehouse

    DeWitt, J.B.; Derby, J.V., Jr.; Mangan, G.F., Jr.

    1955-01-01

    Symptoms appeared when quail and pheasants were fed diets containing 0.025-0.050% DDT. Symptoms appeared sooner as percentages increased. Young birds seemed more resistant than adults. Median lethal quantity for adult quail was about 1,200 mg./Kg. Young quail showed no ill-effects after ingesting 3,000 mg./Kg. during 10-week period. Adult pheasants died after ingesting 200-300 mg./Kg. Approximately 600 mg./Kg. were required to kill young pheasants. Quantities of DDT stored in tissues were not proportional to amounts administered or to duration of exposure, but were related to severity of symptoms. Concentration of DDT in breast muscles of birds killed by DDT was about 34 micrograms/Gm. in adult quail and 22 micrograms/Gm. in adult pheasants.

  14. Residues of DDT in brains and bodies of birds that died on dosage and in survivors

    USGS Publications Warehouse

    Stickel, L.F.; Stickel, W.H.; Christensen, R.

    1966-01-01

    Residues of 1,1 ,l-trichloro-2,2-bis(p-chlorophenyl)-ethane (DDT) and 1,1 -dichloro-2.2-bis(p-chlorophenyl)-ethane (DDD) in brains of cowbirds (Molothrus ater) killed hy dietary dosage of DDT were similar in birds that died after various lengths of time on dosage and in birds that died of delayed effects after as much as 40 days on clean food, Residues of DDT and DDD, but not of 1,1 -dichloro-2.2-bis-(p-chlorophenyl)-ethylene (DDE), were much lower in survivors 112 days after dosage. The relative importance of DDT and DDD in brains could nlot he determined, but DDE appeared not to be critical. Residues in brains of cowbirds were similar to those reported for robins, sparrows, eagles, and white rats. Residues in livers and carcass remainders (with the possible exception of DDD in the liver) appeared unsuitable for diagnosing the cause of death.

  15. Indirect determination of dichlorodiphenyltrichloroethane (DDT) after dechlorination with magnesium/palladium bimetallic particles and potentiometric measurements.

    PubMed

    Estrela, Maria Amélia A; SouzaDe, Jurandir R; Dias, Sílvia C L; Dórea, José G

    2010-05-01

    Determination of chlorine ions of pesticides was performed after dechlorination reaction using a palladium/magnesium system. Chlorine ions were quantified by potentiometry with ion-specific electrode. Rates of dechlorination of 100 microg of DDT as a function of reaction time and percent (wt/wt) of palladium deposited on the magnesium particles were determined. The best reaction conditions to DDT dechlorination were achieved with an acetone/water (1:1) solution and DDT reaction with a 0.27% (wt/wt) palladium/magnesium bimetallic system at room temperature for 10 min. The detection limit was of 0.24 microg/mL. This low cost method showed an efficiency of 92% in determining chlorine ions derived from DDT, it is fast, requiring no specialized laboratory equipment. PMID:20419289

  16. Persistence and transfer of /sup 36/Cl-DDT in the soil and biota of an old-field ecosystem: a six-year balance study

    SciTech Connect

    Forsyth, D.J.; Peterle, T.J.; Bandy, L.W.

    1983-12-01

    The fate of a 1 kg/ha application of granular chlorine-36-labeled DDT made by helicopter on 10 June 1969 to a 4-ha old-field study area near Urbana, Ohio was traced and quantified in soil and biota through November 1974. Between 1970 and 1974, residues of DDT (DDTR, includes DDT plus metabolites) declined from 22.0 to 3.8 mg/kg tissue in earthworms (Lumbricus terrestris) and from 9.3 to 2.1 mg/kg in slugs (Deroceras laeve). Levels of DDTR in foliage of grasses and forbs increased from 2-3 mg/kg in 1970 to 7.6 mg/kg in 1974, but remained relatively constant at 1.6 mg/kg in roots. Amounts of residues in samples of air collected at the surface of the soil were positively correlated with amounts in soil and with air temperature. The total quantity of DDTR in the top 12 cm of soil was estimated to be 1779 g in October 1974, or 38% of the amount applied in 1969. Earthworms, which comprised the largest component of animal biomass, contained 5% of the total DDTR in the ecosystem in 1969, compared to 3% in the plants and other biota. As residues declined in earthworms and increased in plants over time, the total DDTR bound in the biota increased until it accounted for 22% of the total DDTR in the ecosystem in 1974. Losses of DDTR from the ecosystem each year were attributed primarily to volatilization from soil, because losses in runoff and emigrating insects and small mammals were negligible. 12 references, 7 figures, 6 tables.

  17. An assessment of DDT and other chlorinated compounds and the reproductive success of American robins (Turdus migratonrius) breeding in fruit orchards.

    PubMed

    Gill, Harpreet; Wilson, Laurie K; Cheng, Kimberly M; Elliott, John E

    2003-01-01

    Although DDT was banned in the 1970s, American robins (Turdus migratorius) breeding in fruit orchards of the Okanagan Valley, British Columbia, continue to be contaminated with DDT and its metabolites. The objectives of our study were (1) to assess organochlorine (OC) contamination in robins breeding in Okanagan orchards (1993-1995, 1997-1998) and (2) to determine if exposure affected reproductive success when compared to robins from non-orchard habitat (lower mainland, British Columbia). Robins in orchards had total DDT egg residues of 48.64 mg/kg (geometric mean; n = 92) while those in non-orchard habitat had 1.10 mg/kg (geometric mean; n = 26), wet weight. The probability of nest survival during the incubation period was 96.7% (confidence interval: 95.7-97.5%; n = 165) in orchard habitat and 96.7% (confidence interval: 94.6-98.1%; n = 28) in non-orchard habitat. During the nestling period the probability of nest survival was 98.2% (confidence interval: 97.2-98.9%; n = 123) in orchard habitat and 96.2% (confidence interval: 92.8-98.0%; n = 34) in non-orchard habitat. Clutch (p < 0.0001) and brood size (p = 0.0133) were larger in orchards (n = 150 and n = 93, respectively) compared to non-orchard nests (n = 42 and n = 23, respectively) with no difference in fledge rate. DDE (r2 = 0.11, p = 0.0030, n = 68) and dieldrin (r2 = 0.29, p < 0.0001, n = 68) were negatively correlated with fledge rate in robin eggs collected from orchard habitat, however, low r2 values signify minimal biological significance. Although American robins nesting in Okanagan orchards are exposed to high OC levels, reproductive success does not appear to be negatively impacted. PMID:12739861

  18. Elucidating Turnover Pathways of Bioactive Small Molecules by Isotopomer Analysis: The Persistent Organic Pollutant DDT

    PubMed Central

    Ehlers, Ina; Betson, Tatiana R.; Vetter, Walter; Schleucher, Jürgen

    2014-01-01

    The persistent organic pollutant DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane) is still indispensable in the fight against malaria, although DDT and related compounds pose toxicological hazards. Technical DDT contains the dichloro congener DDD (1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethyl]benzene) as by-product, but DDD is also formed by reductive degradation of DDT in the environment. To differentiate between DDD formation pathways, we applied deuterium NMR spectroscopy to measure intramolecular deuterium distributions (2H isotopomer abundances) of DDT and DDD. DDD formed in the technical DDT synthesis was strongly deuterium-enriched at one intramolecular position, which we traced back to 2H/1H fractionation of a chlorination step in the technical synthesis. In contrast, DDD formed by reductive degradation was strongly depleted at the same position, which was due to the incorporation of 2H-depleted hydride equivalents during reductive degradation. Thus, intramolecular isotope distributions give mechanistic information on reaction pathways, and explain a puzzling difference in the whole-molecule 2H/1H ratio between DDT and DDD. In general, our results highlight that intramolecular isotope distributions are essential to interpret whole-molecule isotope ratios. Intramolecular isotope information allows distinguishing pathways of DDD formation, which is important to identify polluters or to assess DDT turnover in the environment. Because intramolecular isotope data directly reflect isotope fractionation of individual chemical reactions, they are broadly applicable to elucidate transformation pathways of small bioactive molecules in chemistry, physiology and environmental science. PMID:25350380

  19. Development and characterization of molecularly imprinted sol-gel materials for the selective detection of DDT.

    PubMed

    Graham, Amy L; Carlson, Catherine A; Edmiston, Paul L

    2002-01-15

    Molecularly imprinting sol-gel materials for DDT using both a noncovalent and a covalent approach was examined. A nonpolar porous sol-gel network was created through the use of the bridged polysilsesquioxane, bis-(trimethoxysilylethyl)benzene (BTEB), as the principal sol-gel component. Noncovalent molecular imprinting was deemed unsuccessful, presumably because of the lack of strong intermolecular interactions that can be established between the DDT and the sol-gel precursor. A covalent imprinting strategy was employed by generating a sacrificial spacer through the reaction of two 3-isocyanatopropyltriethoxysilanes with one of two different template molecules: 4,4'-ethylenedianiline (EDA) or 4,4'-ethylidenebisphenol (EBP). After formation of the sol-gel, the bonds linking the spacer template to the matrix were cleaved in a manner that generated a pocket of the appropriate size bordered by amine groups that could aid in the binding of DDT through weak hydrogen bonding interactions. Experiments indicated that DDT could be bound selectively by such an approch. To generate a sensor, an environmentally sensitive fluorescent probe, 7-nitrobenz-2-oxa-1,3-diazole, (NBD) located adjacent to the DDT binding site was used to transduce the binding of analyte. EDA-imprinted sol-gels, deposited as films on glass microscope slides, were shown to quantitatively detect DDT in water to a limit-of-detection of 50 ppt with a response time of <60 s. Repeat measurements could be made with the same sensing films after rinsing with acetone between each measurement. The EDA sensing material was selective for DDT and other structurally similar molecules. However, the sensing film design was limited by the relatively minor changes in fluorescence intensity upon binding DDT. This situation may be remedied by an alternative methodology that can facilitate attachment of the NBD fluorophore in an optimal position proximal to the binding pocket. PMID:11811423

  20. Bioavailability assessments following biochar and activated carbon amendment in DDT-contaminated soil.

    PubMed

    Denyes, Mackenzie J; Rutter, Allison; Zeeb, Barbara A

    2016-02-01

    The effects of 2.8% w/w granulated activated carbon (GAC) and two types of biochar (Burt's and BlueLeaf) on DDT bioavailability in soil (39 μg/g) were investigated using invertebrates (Eisenia fetida), plants (Cucurbita pepo spp. pepo) and a polyoxymethylene (POM) passive sampler method. Biochar significantly reduced DDT accumulation in E. fetida (49%) and showed no detrimental effects to invertebrate health. In contrast, addition of GAC caused significant toxic effects (invertebrate avoidance and decreased weight) and did not significantly reduce the accumulation of DDT into invertebrate tissue. None of the carbon amendments reduced plant uptake of DDT. Bioaccumulation of 4,4'DDT and 4,4'-DDE in plants (C. pepo spp. pepo) and invertebrates (E. fetida) was assessed using bioaccumulation factors (BAFs) and compared to predicted bioavailability using the freely-dissolved porewater obtained from a polyoxymethylene (POM) equilibrium biomimetic method. The bioavailable fraction predicted by the POM samplers correlated well with measured invertebrate uptake (<50% variability), but was different from plant root uptake by 134%. A literature review of C. pepo BAFs across DDT soil contamination levels and the inclusion of field data from a 2.5 μg/g DDT-contaminated site found that these plants exhibit a concentration threshold effect at [DDT](soil) > 10 μg/g. The results of these studies illustrate the importance of including plants in bioavailability studies as the use of carbon materials for in situ contaminant sorption moves from predominantly sediment to soil remediation technologies. PMID:26495827

  1. Application of high frequency ultrasound in the destruction of DDT in contaminated sand and water.

    PubMed

    Thangavadivel, Kandasamy; Megharaj, Mallavarapu; Smart, Roger St C; Lesniewski, Peter J; Naidu, Ravi

    2009-09-15

    High frequency ultrasound, as an alternative to high cost incineration, has been investigated to remediate DDT from sand and soil slurries. In this study, low power high frequency ultrasound (1.6 MHz; 150 W/L), with operating costs much lower than low frequency ultrasound, has been used to remediate DDT in liquid solution and in sand slurries. At 1.6 MHz, the wavelength, cycle time, bubble size and bubble life time are much smaller and the number of bubbles per litre is much larger than at frequencies below 50 kHz. These large differences affect the effective mass transfer to the bubbles and subsequent energy release, hydrolysis of water and degradation mechanism. Based on DDT measurement, using high frequency ultrasound, 90% of 8 mg/L of DDT from liquid solution was destroyed in 90 min. Removal efficiency from 32.6 mg/L of DDT in a 40 wt.% sand slurry was 22% in 90 min. Other slurry and DDT combinations are reported. Incremental chloride measurements indicated that combination of ultrasound and iron powder helps to increase the remediation rate of DDT from sand slurry, e.g. 46% cf. 32% for a 20 wt.% slurry. The results show that high frequency ultrasound is effective in degrading the non-polar pollutant DDT dispersed in water and in sand slurry. In practice, due to intensity limitations in currently available equipment and higher attenuation of energy, high frequency ultrasound has a low volume coverage and would require circulation of the slurry past the sonotrode, multiple sonotrodes, larger sonotrode area and lower slurry densities may still be required. PMID:19346068

  2. Residues of DDT, dieldrin, and heptachlor in earthworms during two years following application

    USGS Publications Warehouse

    Gish, C.D.; Hughes, D.L.

    1982-01-01

    Study was conducted at the Patuxent Wildlife Research Center in December 1963. Plots were treated with DDT, dieldrin, or heptachlor. Earthworms and soils were sampled from each plot when treated and 0.5, 1.2, 4, 6, 8, 10, 12, 16, 20 and 24 months thereafter. Samples were analyzed by gas chromatography for residues of aldrin, dieldrin, endrin, heptachlor, heptachlor epoxide, chlordane, BHC, DDT and DDE.

  3. DDT, global strategies, and a malaria control crisis in South America.

    PubMed Central

    Roberts, D. R.; Laughlin, L. L.; Hsheih, P.; Legters, L. J.

    1997-01-01

    Malaria is reemerging in endemic-disease countries of South America. We examined the rate of real growth in annual parasite indexes (API) by adjusting APIs for all years to the annual blood examination rate of 1965 for each country. The standardized APIs calculated for Brazil, Peru, Guyana, and for 18 other malaria-endemic countries of the Americas presented a consistent pattern of low rates up through the late 1970s, followed by geometric growth in malaria incidence in subsequent years. True growth in malaria incidence corresponds temporally with changes in global strategies for malaria control. Underlying the concordance of these events is a causal link between decreased spraying of homes with DDT and increased malaria; two regression models defining this link showed statistically significant negative relationships between APIs and house-spray rates. Separate analyses of data from 1993 to 1995 showed that countries that have recently discontinued their spray programs are reporting large increases in malaria incidence. Ecuador, which has increased use of DDT since 1993, is the only country reporting a large reduction (61%) in malaria rates since 1993. DDT use for malaria control and application of the Global Malaria Control Strategy to the Americas should be subjects of urgent national and international debate. We discuss the recent actions to ban DDT, the health costs of such a ban, perspectives on DDT use in agriculture versus malaria control, and costs versus benefits of DDT and alternative insecticides. PMID:9284373

  4. Model ecosystem determination of the metabolic and environmental fate of tetrachloro-DDT

    SciTech Connect

    Cole, R.B.; Metcalf, R.L.

    1987-01-01

    A potential hazardous waste site investigation was conducted by the Environmental Protection Agency to determine whether ground water, surface water, or area soils and sediments were contaminated as a result of waster water discharges or improper solid waste disposal practices of a pesticide manufacturer. One of the compounds discharged into the environment was 1,1,1,2-tetrachloro-2,2-bis(p-chlorophenyl)ethane, commonly referred to as tetrachloro-DDT. Unlike a great many of the DDT analogs, tetrachloro-DDT has come under only limited scrutiny, mainly because it was dismissed as having poor insecticidal properties relative to DDT and other analogs. Its metabolism in ingesting organisms, and degradative pathways in the environment have consequently been left uncertain. This model ecosystem study was undertaken to examine the unanswered questions concerning the metabolic and environmental fate of tetrachloro-DDT. The relevance of this study pertains to disposal practices of pesticide manufacturers who use tetrachloro-DDT as a product precursor.

  5. Recognition and Detoxification of the Insecticide DDT by Drosophila melanogaster Glutathione S-Transferase D1

    SciTech Connect

    Low, Wai Yee; Feil, Susanne C.; Ng, Hooi Ling; Gorman, Michael A.; Morton, Craig J.; Pyke, James; McConville, Malcolm J.; Bieri, Michael; Mok, Yee-Foong; Robin, Charles; Gooley, Paul R.; Parker, Michael W.; Batterham, Philip

    2010-06-14

    GSTD1 is one of several insect glutathione S-transferases capable of metabolizing the insecticide DDT. Here we use crystallography and NMR to elucidate the binding of DDT and glutathione to GSTD1. The crystal structure of Drosophila melanogaster GSTD1 has been determined to 1.1 {angstrom} resolution, which reveals that the enzyme adopts the canonical GST fold but with a partially occluded active site caused by the packing of a C-terminal helix against one wall of the binding site for substrates. This helix would need to unwind or be displaced to enable catalysis. When the C-terminal helix is removed from the model of the crystal structure, DDT can be computationally docked into the active site in an orientation favoring catalysis. Two-dimensional {sup 1}H,{sup 15}N heteronuclear single-quantum coherence NMR experiments of GSTD1 indicate that conformational changes occur upon glutathione and DDT binding and the residues that broaden upon DDT binding support the predicted binding site. We also show that the ancestral GSTD1 is likely to have possessed DDT dehydrochlorinase activity because both GSTD1 from D. melanogaster and its sibling species, Drosophila simulans, have this activity.

  6. Development of a laser ignited all secondary explosive DDT detonator

    SciTech Connect

    Woods, C.M.; Spangler, E.M.; Beckman, T.M.; Kramer, D.P.

    1992-09-01

    A hermetic, stand alone, laser-ignited deflagration-to-detonation transition (DDT) detonator has been developed. The detonator uses the secondary explosive HMX (cyclotetramethylenetetranitramine) and was originally developed for use with the US Navy`s Laser Initiated Transfer Energy subsystem (LITES). The design of the new detonator allows for its use with a variety of laser fire sets. A high density blend 6f 830 cm2/g HMX with 3% carbon black by weight was used for the ignition charge. Deflagration-to-detonation transition was achieved with a transition charge of undoped 830 cm2/g HMX. Using a 12-ms ND-YAG laser pulse coupled to the detonator via a 1-mm diameter optical fiber, the ignition threshold was determined to be approximately 30 mJ. Full detonating outputs were demonstrated by function testing in Navy detonation sensitivity fittings. Finally, the detonator was tested in several configurations with shielded mild detonating chord (SNMC) endrips to determine its capability for lighting transfer lines.

  7. Differential transcription of cytochrome P450s and glutathione S transferases in DDT-susceptible and resistant Drosophila melanogaster strains in response to DDT and oxidative stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Metabolic DDT resistance in Drosophila melanogaster has previously been associated with constitutive over-transcription of cytochrome P450s. Increased P450 activity has also been associated with increased oxidative stress. In contrast, over-transcription of glutathione S transferases (GSTs) has been...

  8. The search for reliable aqueous solubility (Sw) and octanol-water partition coefficient (Kow) data for hydrophobic organic compounds; DDT and DDE as a case study

    USGS Publications Warehouse

    Pontolillo, James; Eganhouse, R.P.

    2001-01-01

    The accurate determination of an organic contaminant?s physico-chemical properties is essential for predicting its environmental impact and fate. Approximately 700 publications (1944?2001) were reviewed and all known aqueous solubilities (Sw) and octanol-water partition coefficients (Kow) for the organochlorine pesticide, DDT, and its persistent metabolite, DDE were compiled and examined. Two problems are evident with the available database: 1) egregious errors in reporting data and references, and 2) poor data quality and/or inadequate documentation of procedures. The published literature (particularly the collative literature such as compilation articles and handbooks) is characterized by a preponderance of unnecessary data duplication. Numerous data and citation errors are also present in the literature. The percentage of original Sw and Kow data in compilations has decreased with time, and in the most recent publications (1994?97) it composes only 6?26 percent of the reported data. The variability of original DDT/DDE Sw and Kow data spans 2?4 orders of magnitude, and there is little indication that the uncertainty in these properties has declined over the last 5 decades. A criteria-based evaluation of DDT/DDE Sw and Kow data sources shows that 95?100 percent of the database literature is of poor or unevaluatable quality. The accuracy and reliability of the vast majority of the data are unknown due to inadequate documentation of the methods of determination used by the authors. [For example, estimates of precision have been reported for only 20 percent of experimental Sw data and 10 percent of experimental Kow data.] Computational methods for estimating these parameters have been increasingly substituted for direct or indirect experimental determination despite the fact that the data used for model development and validation may be of unknown reliability. Because of the prevalence of errors, the lack of methodological documentation, and unsatisfactory data

  9. Cycling of DDT in the global environment 1950-2002: World ocean returns the pollutant

    NASA Astrophysics Data System (ADS)

    Stemmler, Irene; Lammel, Gerhard

    2009-12-01

    The global distribution and fate of the insecticide DDT was modeled for the first time using a spatially resolved global multicompartment chemistry-transport model comprising a 3D coupled atmosphere and ocean GCM, coupled to 2D vegetation surfaces and top soils. DDT enters the model environment as a pesticide in agriculture only. Final sinks of DDT in the total environment are degradation in air (hydroxyl radical reaction), on vegetation surfaces, in ocean sediments and soils. The process resolution of the ocean compartment, i.e., either a fixed or variable size and sinking velocity of suspended particles, has almost no effect on the large-scale cycling and fate of DDT. The residence times in various ocean basins were declining but varied regionally. The global ocean absorbed until 1977 and since then has been losing DDT, while large sea areas are still accumulating the pollutant. The main sink is volatilization to the atmosphere. In 1990, the year when emissions ceased, 292 kt of DDT were deposited to the global ocean, 301 kt were volatilized, and 41 kt were exported from the surface layer to the deeper levels. The sea region that has been representing the most significant (secondary) DDT source is the western N Atlantic (Gulf stream and N Atlantic Drift regions). It has been a source since approximately 1970. Also large parts of the tropical ocean and the southern mid-latitude ocean have turned net volatilizational (i.e., volatilization flux > deposition flux) during the 1980s. Despite the emissions migrating southward as a consequence of substance ban in mid latitudes, the geographic distribution of the contaminant (and, hence, environmental exposure) has been migrating steadily northward since the 1960s.

  10. Comparative use of bendiocarb and DDT to control Anopheles pseudopunctipennis in a malarious area of Mexico.

    PubMed

    Loyola, E G; Vaca, M A; Bown, D N; Pérez, E; Rodriguez, M H

    1991-04-01

    The state of Sinaloa has one of the highest and most persistent malaria transmission levels in Mexico. Due to this situation, with resistance of the vector Anopheles pseudopunctipennis Theobald to DDT, the carbamate insecticide bendiocarb was evaluated as an alternative to DDT for residual house-spraying in village-scale trials during 1985-87. Application rates of the active ingredient per square metre of sprayable surface (ai/m2) were 0.4 g bendiocarb 80% wettable powder (80WP) and 2 g DDT 75% WP. Both insecticides failed to control mosquito populations. Human-bait mosquito densities were not altered as a result of insecticide spraying and human-bait collected mosquito mortality rates were low, suggesting little pre-biting insecticide contact due to avoidance or insufficient resting time indoors. Lower densities of indoor-resting mosquitoes were observed with DDT as opposed to bendiocarb treated houses. Anopheline mortality was higher (98-100%) when exposed for 1 h to 1% bendiocarb in standard WHO susceptibility tests and wall bioassays. Mortality-rates of 15-48% due to 1 h exposure to 4% DDT indicated that this insecticide may continue to be partially effective. House curtain and mark-recapture mosquito studies indicated that DDT produced higher excito-repellency than bendiocarb, as reflected by more mosquito landings but lower feeding rates, shorter resting period and earlier exit time from DDT sprayed houses. In the absence of insecticide, more than 50% of blood-fed An.pseudopunctipennis females exited from houses within 2-4 h of release, showing exophilic behaviour. The outdoor/indoor density ratio indicated that the majority were exophagic. These behavioural characteristics limit the usefulness of any residual insecticide against An.pseudopunctipennis. PMID:1768914

  11. The primary evaluation and characterization of obsolete DDT pesticide from a precalciner of a cement kiln.

    PubMed

    Li, Yang; Wang, Qi; Huang, Qifei; He, Jie

    2014-01-01

    1,1,1-Trichloro-2,2-bi(4-chlorophenyl)ethane (DDT) pesticide that has been extensively used in agriculture in China in the last century, and even now, has been banned from all purposes. The disposal of obsolete DDT pesticide has been an urgent task for the Chinese government. In order to evaluate the feasibility of co-processing DDT in the current new style dry-process rotary kiln with a precalciner as the feeding point, the destruction efficiency (DE) of DDTs (including p,p(')-DDT, o,p(')-DDT, p,p(')-DDE and p,p(')-DDD), proportion of DDTs in the combustion residue and exhaust gas, and the release of chlorine were studied under different operating conditions of temperature, oxygen content and gas retention time in the laboratory. The DE of DDTs exceeded 99% when the temperature was over 800 °C with enough oxygen. As the temperature increased from 600 °C to 1200 °C, the proportion of p,p(')-DDD increased and p,p(')-DDT decreased but still the main effective component remained in the combustion residue. In the exhaust gas, the most dominant phenomenon was the rapid increase in p,p(')-DDE concentration as the temperature increased. The release of chlorine reached a peak between 800 °C and 900 °C. It was found that the oxygen content had a positive correlation with the process of dechlorination. The proportion of p,p(')-DDE increased as the oxygen content was increased in the exhaust gas. The gas retention time had almost no influenced on the DE of DDTs, but affected the degradation extent of DDTs in the gas phase. These experiments showed that co-processing of obsolete DDT pesticide in cement kiln precalciners is feasible. PMID:25176484

  12. First report of the concentrations and implications of DDT residues in chicken eggs from a malaria-controlled area.

    PubMed

    Bouwman, Hindrik; Bornman, Riana; van Dyk, Cobus; Barnhoorn, Irene

    2015-10-01

    In malaria-endemic areas, where DDT is still used for vector control by indoor residual spraying (IRS), the concentrations of DDT in human blood and breast milk are high, and there are indications of human health impacts. To identify the possible avenues of exposure reduction, we created the concept of a Total Homestead Environment Approach (THEA). THEA characterizes the interactions between DDT, humans, and the biota within and around homesteads. One dietary route of human exposure and uptake of DDT, namely, chicken egg consumption, has to our knowledge never been studied. The ΣDDT in eggs from a DDT-sprayed village ranged between 5200 and 48,000 ng/g wm (wet mass), with a median of 11,000 ng/g wm. On a lipid mass-basis (lm), the mean ΣDDT for eggs from the sprayed village was 100,000 ng/g lm. The maximum egg concentration observed was three orders of magnitude higher than the median. The acceptable daily intake (ADI) was not exceeded based on the consumption of three eggs per week for a 60 kg person. This equates to an intake of 0.089 g DDT per person per year. Chicken egg consumption is therefore a possible target for exposure reduction, probably best achieved by reducing the DDT concentrations in soils. PMID:26197434

  13. Effect of organic matter additions on uptake of weathered DDT by Cucurbita pepo ssp. pepo cv. Howden.

    PubMed

    Lunney, Alissa I; Rutter, Allison; Zeeb, Barbara A

    2010-01-01

    Greenhouse studies were conducted to assess the impact of organic matter additions on plant uptake of DDT [2,2-bis(chlorophenyl)-1,1,1-trichloroethane] from weathered soil. Cucurbita pepo ssp. pepo cv. Howden pumpkins were grown in 100 g of DDT contaminated soil ([DDT] - 1100 ng/g) mixed with equal volumes of either clean soil, perlite, vermiculite, peat, potting soil, or granular activated carbon (GAC) to give total organic carbon contents of 2.4%, 2.5%, 2.6%, 11.5%, 12.2%, and 27.3%, respectively. As in other studies, root DDT concentrations were significantly lower in soils with high organic matter. Root bioaccumulation factors (BAF = [DDT]root/[DDT]soil) approximated this trend. Root concentrations correlated with organic matter concentrations and not with soil DDT concentrations. Conversely, shoot DDT concentrations, shoot BAFs and translocation factors (TLF = BAF(shoot)/BAF(root)) were not significantly different between treatment groups, except for plants grown in GAC/DDT soil. This suggests that amendments with a range of organic matter contents may be added to improve soil conditions at industrial sites without significant adverse effects on phytoextraction potential of C. pepo ssp. pepo. PMID:20734916

  14. Survival, growth, detoxifying and antioxidative responses of earthworms (Eisenia fetida) exposed to soils with industrial DDT contamination.

    PubMed

    Shi, Yajuan; Zhang, Qiangbin; Huang, Dunqi; Zheng, Xiaoqi; Shi, Yajing

    2016-03-01

    The survival, growth, activity of the biotransformation system phase II enzyme glutathione-S-transferase (GST) and the oxidative defense enzyme catalase (CAT) of earthworms exposed to the contaminated soils from a former DDT plant and reference soils were investigated, and compared with the corresponding indicators in simulated soil-earthworm system, unpolluted natural soils with spiked-in DDT series, to identify the toxic effects of DDT on earthworms and their cellular defense system in complex soil system. The results indicated that DDT level in the contaminated soils was significantly higher than that in the reference soils with similar level of other pollutants and soil characters. The mortality, growth inhibition rates, GST and CST activities of earthworms exposed to the contaminated soils were significantly higher than that in reference soils. The contribution of historical DDT in contaminated soils to earthworms was confirmed by the DDT spiked tests. DDT spiked in soils at rates of higher than 200 mg·kg(-1) was significantly toxic to both the survival and the growth of earthworms. DDT significantly stimulated GST and CAT activity in earthworms after 14 days. The CAT and GST activities were also stimulated by DDT exposure at rates of 100 mg·kg(-1) after chronic exposure (42 days). The results provide implications for validating the extrapolation from laboratory simulated soils criteria to contaminated soils and for making site risk assessments. PMID:26969436

  15. Influence of Cougar Reservoir Drawdown on Sediment and DDT Transport and Deposition in the McKenzie River Basin, Oregon, Water Years 2002-04

    USGS Publications Warehouse

    Anderson, Chauncey W.

    2007-01-01

    bags, was greatest downstream of Cougar and Blue River Reservoirs (1.0 and 1.2 percent of total sediments, respectively). Deposition was least in the high-energy, unregulated environments (about 0.25 percent) of the South Fork McKenzie River above Cougar Reservoir and in the mainstem above the South Fork, and intermediate near Vida, the most downstream site on the mainstem. DDT, applied throughout much of the upper McKenzie River drainage basin to control spruce budworm during the 1950s, was detected in the South Fork near Rainbow in the form of its metabolites DDD and DDE in fine sediment captured in the infiltration bags. DDE also was detected in infiltration bags deployed in the McKenzie River near Vida, downstream of the South Fork. All concentrations of DDD and DDE were less than the aquatic-life criterion for bed sediment. DDT species were not detected in water samples, including samples collected during large storms. The reservoir apparently acted as a trap for sediment and DDT throughout the course of its existence, facilitating degradation of the trapped DDT, and may have been a source for both during the construction period in 2002-05, but the lack of detections during storms indicates that DDT transport was small. Transport of detectable amounts of DDT likely was limited to periods of high suspended-sediment concentrations (greater than 75-100 milligrams per liter). Infiltration bags were deployed during August 2003-July 2004 and were a useful device for measuring fine-sediment deposition and for chemical analysis of the deposited material. Deposition of fine-grained sediment downstream of the flood-control dams may be reduced if bed-moving events can be periodically reintroduced to those reaches.

  16. DDT (2,2,bis(p-chlorophenyl) 1,1,1-trichloroethane) induced structural changes in adrenal glands of rats

    SciTech Connect

    Chowdhury, A.R.; Gautam, A.K.; Venkatakrishna-Bhatt, H. )

    1990-08-01

    Oldest chlorinated hydrocarbon insecticide, DDT was used widely to control pest and vector borne diseases in developing countries. Malaria and vector borne diseases can be econometrically controlled by DDT. Chronic and acute exposures to DDT result in systemic disorders in human as well as this confirmed in animals. Experimental study revealed that DDT caused the structural and functional changes in thyroid and reproductive system. The effects of DDT on adrenal glands are not well documented. Therefore this experimental investigation was undertaken to evaluate the histomorphological changes of adrenal gland after the treatment with DDT in rats.

  17. Flame acceleration and DDT in channels with obstacles: Effect of obstacle spacing

    SciTech Connect

    Gamezo, Vadim N.; Oran, Elaine S.; Ogawa, Takanobu

    2008-10-15

    We study flame acceleration and deflagration-to-detonation transition (DDT) in obstructed channels using 2D reactive Navier-Stokes numerical simulations. The energy release rate for the stoichiometric hydrogen-air mixture is modeled by one-step Arrhenius kinetics. Computations performed for channels with symmetrical and staggered obstacle configurations show two main effects of obstacle spacing S. First, more obstacles per unit length create more perturbations that increase the flame surface area more quickly, and therefore the flame speed grows faster. Second, DDT occurs more easily when the obstacle spacing is large enough for Mach stems to form between obstacles. These two effects are responsible for three different regimes of flame acceleration and DDT observed in simulations: (1) Detonation is ignited when a Mach stem formed by the diffracting shock reflecting from the side wall collides with an obstacle, (2) Mach stems do not form, and the detonation is not ignited, and (3) Mach stems do not form, but the leading shock becomes strong enough to ignite a detonation by direct collision with the top of an obstacle. Regime 3 is observed for small S and involves multiple isolated detonations that appear between obstacles and play a key role in final stages of flame and shock acceleration. For Regime 1 and staggered obstacle configurations, we observe resonance phenomena that significantly reduce the DDT time when S/2 is comparable to the channel width. Effects of imposed symmetry and stochasticity on DDT phenomena are also considered. (author)

  18. Investigations on the mechanism of DDT resistance in certain anopheline mosquitos*

    PubMed Central

    Perry, Albert S.

    1960-01-01

    DDT resistance, first observed some thirteen years ago in houseflies, is rapidly spreading in an alarming number of other insects of public health importance, particularly mosquitos. But while much has been learned of the mechanism of this resistance in houseflies, little is known as yet of the corresponding mechanism in mosquitos. A WHO-sponsored study was designed to find out primarily whether, as in houseflies, the breakdown of DDT to DDE—a non-toxic metabolite—in vivo is the predominant factor responsible for the development of resistance in anopheline mosquitos. No definite correlation could be established between the detoxication of DDT and resistance in the anophelines tested, but the interesting fact emerged that the detoxication potential was a measure of the ratio of DDE to absorbed DDT rather than of the ratio of DDT recovered. A multiplicity of factors governs the development of resistance in mosquitos, each species possessing a ”combination of attributes for resistance” that may differ from that of other species; some of these are discussed. PMID:14432018

  19. Distribution of DDT residues in fish from the Songkhla Lake, Thailand.

    PubMed

    Kumblad, L; Olsson, A; Koutny, V; Berg, H

    2001-01-01

    Since the early 1950s DDT has been extensively used in Thailand as a malaria repellent and as an agricultural pesticide, but was finally banned in 1994. In this study concentrations of p,p'-DDT, p,p'-DDE, and p,p'-DDD in 113 fish of four species (Scatophagus argus, Protosus canius, Channa striata and Zonichthys nigrofasciata) are reported from the large, brackish Songkhla Lake and the Gulf of Thailand. The mean sigma DDT concentrations at different locations in the analysed fish species ranged from 33 to 170 ng/g lipid wt. (0.086-7.7 ng/g fresh wt.). This is well below the recommended maximum residue levels in aquatic animals used for human consumption (5000 ng/g fresh wt.) in Thailand. The comparatively low residue levels could be due to the high temperature and solar radiation in the region, which may result in a high volatilising and degradation rate of DDT. Also, the high productivity of the lake could result in a dilution effect, when DDT is distributed in a large amount of organic matter, followed by a high biological degradation of the substance. PMID:11234535

  20. Photosensitized reduction of DDT using visible light: the intermediates and pathways of dechlorination.

    PubMed

    Lin, Chitsan; Chang, Tien-Chin

    2007-01-01

    A reaction mixture containing DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane), methylene green (as the photosensitizer), and triethylamine (as the electron donor) in acetonitrile:water (1:1) was irradiated by an ordinary 150-W GE-Miser spotlight to facilitate visible-light photosensitized DDT dehalogenation. The intermediates and reaction products were identified by GC/MS (gas chromatography/mass spectrometer) and NMR (nuclear magnetic resonance). The photosensitized dehalogenation method partially degraded DDT via an electron transfer relay mechanism. Results indicate that DDT lost about three chlorines after a total of 19 days of irradiation. Aliphatic chlorines were found to be removed easier than aromatic chlorines. Various types of reductants were compared for electron donation efficiency, and photosensitizer concentration was optimized for our reaction system. In most cases, clean and simple dechlorinated products were observed. The proposed photosensitized reduction was coexisted with a thermal elimination effect for the first chlorine removal of DDT, and the photosensitized electron transfer reduction was shown to be the dominating mechanism responsible for further dechlorination after the initial stage. A sequential dechlorination pathway was proposed, with each successive dehalogenation, the reaction proceeds more slowly. The results have shown the feasibility of utilizing visible light, nontoxic dyes and electron donors to render a toxic compound less toxic and to enhance the natural carbon regeneration rates. PMID:16949127

  1. Persistence in earthworms and potential hazards to birds of soil applied DDT, dieldrin, and heptachlor

    USGS Publications Warehouse

    Beyer, W.N.; Gish, C.D.

    1980-01-01

    (1) DDT, dieldrin, and heptachlor were each applied to separate replicate plots in a hay field at 0.6, 2.2, or 9.0 kg/ha. For 11 yr thereafter, soil and earthworms were analysed for residues. (2) The average ratios of residues in earthworms (dry weight) to residues in soil (dry weight) were: total DDT, 5; dieldrin, 8; and heptachlor epoxide, 10. The average time for the initial residues in soil to be reduced by 50% were: total DDT, 3.2 yr; dieldrin, 5.1 yr; and heptachlor epoxide, 3.2 yr. The corresponding times for residues in earthworms were: total DDT, 3.2 yr; dieldrin, 2.6 yr; and heptachlor epoxide, 3.0 yr. (3) DDE was most persistent, and in plots treated at 9.0 kg/ha its concentration remained constant at about 0.4 ppm in soil and about 7 ppm in earthworms. (4) When applied at 9.0 kg/ha, DDT accumulated in earthworms to concentrations (32 ppm) which laboratory studies have shown to be hazardous to some sensitive bird species. When heptachlor was applied at 2.2 or 9.0 kg/ha, heptachlor epoxide in earthworms reached concentrations (8 ppm) potentially hazardous to woodcock. Dieldrin remained at potentially hazardous concentrations (8 ppm) for 3 yr in plots treated with 2.2 kg/ha and for 11 yr in plots treated with 9.0 kg/ha.

  2. Effect of wall conditions on DDT in hydrogen-oxygen mixtures

    NASA Astrophysics Data System (ADS)

    Fukuda, Motoki; Dzieminska, Edyta; Hayashi, A. Koichi; Yamada, Eisuke; Tsuboi, Nobuyuki

    2013-05-01

    Detonation in ducts is usually studied assuming adiabatic walls because of the high kinetic energy due to the incoming flow being supersonic. In the present work, numerical simulations of deflagration-to-detonation transition (DDT) using a detailed chemical reaction model are performed under adiabatic and isothermal boundary conditions in a tube with no-slip walls. The results show a local explosion driving DDT, which occurs near the tube wall in the case of an adiabatic wall, but close to the flame front in the case of an isothermal wall. Furthermore, to examine the effects of a turbulent boundary layer, a simulation using the Baldwin-Lomax turbulence model is carried out. In the case of the isothermal wall, there is again a local explosion near the tube wall, which leads to detonation. In summary, the present study confirms that the boundary conditions affect the transition to detonation and that the boundary layer is a key component of DDT.

  3. Transient power supply voltage (v{sub DDT}) analysis for detecting IC defects

    SciTech Connect

    Cole, E.I. Jr.; Soden, J.M.; Beegle, R.W.

    1997-04-01

    Transient power supply voltage (V{sub DDT}) analysis is a new testing technique demonstrated as a powerful alternative and complement to I{sub DDQ} testing. V{sub DDT} takes advantage of the limited response time of a voltage supply to the changing power demands of an IC during operation. Changes in the V{sub DD} response time are used to detect increases in power demand with resolutions of 100 nA at 100 kHz, 1 {mu}A at 1 MHz, and 2.5 {mu}A at 1.5 MHz. These current sensitivities have been shown for ICs with quiescent currents < 0.1 {mu}A and > 300 {mu}A. The V{sub DDT} signal acquisition protocols, frequency versus sensitivity tradeoffs, hardware considerations and limitations, data examples, and areas for future research are described.

  4. Effects of DDT on birds at the Patuxent Wildlife Research Refuge

    USGS Publications Warehouse

    Stewart, R.E.; Cope, J.B.; Robbins, C.S.; Brainerd, J.W.

    1946-01-01

    The spraying of DDT at the rate of 2 pounds per acre on a tract of land within the well-drained bottomland forest at the Patuxent Research Refuge on June 5, 1945, had little or no effect on the bird population of the area, with the possible exception of the redstart (Setophaga ruticilla). Considerable evidence was accumulated showing that this species was probably somewhat reduced. The effective dose for the treated area as a whole was decidedly less than 2 pounds of DDT per acre. Some spray was blown away to be deposited on nearby areas, and much of it was screened out by the dense forest canopy. The redstarts, being tree top feeders, were exposed to more DDT than most of the local birds.

  5. Reactive metabolites and agranulocytosis.

    PubMed

    Uetrecht, J P

    1996-01-01

    Central to most hypotheses of the mechanism of idiosyncratic drug-induced blood dyscrasias is the involvement of reactive metabolites. In view of the reactive nature of the majority of such metabolites, it is likely that they are formed by, or in close proximity to the blood cells affected. The major oxidative system of neutrophils generates hypochlorous acid. We have demonstrated that the drugs associated with the highest incidence of agranulocytosis are oxidized to reactive metabolites by hypochlorous acid and/or activated neutrophils. There are many mechanisms by which such reactive metabolites could induce agranulocytosis. In the case of aminopyrine-induced agranulocytosis, most cases appear to involve drug-dependent anti-neutrophil antibodies, and these are likely to be induced by cell membrane antigens modified by the reactive metabolite of aminopyrine. The target of agranulocytosis associated with many other drugs is usually neutrophil precursors and may involve cytotoxicity or a cell-mediated immune reaction induced by a reactive metabolite. In the case of aplastic anaemia, there is evidence in some cases for involvement of cytotoxic T cells, which could either be induced by metabolites generated by neutrophils, or more likely, by reactive metabolites generated by stem cells. PMID:8987247

  6. Advances in metabolite identification.

    PubMed

    Wishart, David S

    2011-08-01

    One of the central challenges to metabolomics is metabolite identification. Regardless of whether one uses so-called 'targeted' or 'untargeted' metabolomics, eventually all paths lead to the requirement of identifying (and quantifying) certain key metabolites. Indeed, without metabolite identification, the results of any metabolomic analysis are biologically and chemically uninterpretable. Given the chemical diversity of most metabolomes and the character of most metabolomic data, metabolite identification is intrinsically difficult. Consequently a great deal of effort in metabolomics over the past decade has been focused on making metabolite identification better, faster and cheaper. This review describes some of the newly emerging techniques or technologies in metabolomics that are making metabolite identification easier and more robust. In particular, it focuses on advances in metabolite identification that have occurred over the past 2 to 3 years concerning the technologies, methodologies and software as applied to NMR, MS and separation science. The strengths and limitations of some of these approaches are discussed along with some of the important trends in metabolite identification. PMID:21827274

  7. Analysis of DDT residues in soil by ELISA: an international interlaboratory study.

    PubMed

    Maestroni, B M; Skerritt, J H; Ferris, I G; Ambrus, A

    2001-01-01

    An international interlaboratory study was conducted to determine the performance of a group of laboratories from developing and developed countries. The study used a commercial microwell ELISA on unknown samples spiked with different levels of DDT. The study design was based on Youden pairs and balanced replicates. Two soils, differing in particle size distributions, organic matter content, and cation-exchange capacities and thought to be DDT-free, were spiked at 5 DDT levels between 0.025 and 2 mg/kg. Nineteen laboratories in 17 countries took part in the collaborative trial; of these, the majority were modestly equipped laboratories in developing countries. Samples were analyzed without filtration or cleanup and using standards of pure DDT in methanol. Data were analyzed for repeatability and reproducibility, and average recoveries at the spike levels were calculated. Mean real recoveries for both soils were similar (103% for soil A and 100% for soil B), with values between 0.1 and 2 mg/kg DDT. Precision estimates were best in the linear working range of the assay (0.1-0.5 mg/kg DDT), with reproducibility relative standard deviations (RSDR) typically averaging about 38 and 46% near the upper and lower detection limits, respectively. Corresponding repeatability relative standard deviation (RSDr) values were 20-36% and 36-57%. Thus, even though much of the trial was performed under developing country conditions, performance statistics were similar to other reported results obtained with ELISAs on small molecules of agricultural importance, such as mycotoxins and pesticide and antibiotic residues. PMID:11234800

  8. Effects on forest birds of DDT used for gypsy moth control in Pennsylvania

    USGS Publications Warehouse

    Hotchkiss, N.; Pough, R.H.

    1946-01-01

    1. Systematic censuses of the birds on three 40-acre tracts of forest near Scranton, Lackawanna County, Pennsylvania, were made between May 1 and June 27, 1945, to determine the breeding populations....2. Between May 24 and June 1 a 600-acre area enclosing the first (Mile Square) was sprayed by airplane with DDT in oil solution at 5 pounds per acre. On June 9 a 350-acre area enclosing the second tract (Maple Lake) was sprayed with 1pound of DDT per acre. The third tract (Check) was not treated....3. Within 48 hours after treatment of the Mile Square tract, five sick birds were found with symptoms of DDT poisoning, and all died. Two other dead birds were found, and two nests apparently were abandoned. Species involved were red-eyed vireo (3), black-and-white warbler, black-throated blue warbler (nest abandoned), ovenbird (bird died, nest abandoned), redstart, and scarlet tanager....Within 48 hours after application of DDT to the final portion of the tract (on June 1) the population of living birds appeared to have been much reduced, and this condition continued. Before spraying the population total for all species was 1.6 pairs (3.2 birds) per acre. Three days after spraying had been completed there were only two singing males in the entire area; but on June 13 the estimated population was 0.5 bird per acre.....4. After DDT was applied to the Maple Lake tract, careful watch was kept for changes in the bird population and as to nest conditions there and on the Check tract. The apparent total reduction for all species in the Maple Lake tract was from 2.7 pairs to 2.6 pairs per acre; and in the Check tract from 2.7 pairs to 2.4 pairs per acre. Neither these changes nor the observed abandonment of nests and nestling mortality could be attributed to use of DDT.

  9. Destruction of DDT wastes in two preheater/precalciner cement kilns in China.

    PubMed

    Yan, Dahai; Peng, Zheng; Karstensen, Kåre Helge; Ding, Qiong; Wang, Kaixiang; Wang, Zuguang

    2014-04-01

    The destruction of DDT formulations and DDT contaminated soil was conducted by feeding wastes into the flue gas chamber at the kiln inlet of two different preheater/precalciner cement kilns in China. The concentration of DDT, PCDD/PCDFs and HCB were measured in the flue gas of the main stack, in the solid material under baseline conditions and when feeding DDT-wastes. The destruction efficiency and the destruction and removal efficiency for DDT were in the range of 99.9335%-99.9998% and 99.9984%-99.9999%, respectively. The emissions of PCDD/PCDFs and HCB in the flue gas varied in the range of 0.0019-0.0171 ng I-TEQ/Nm(3) and 0.0064-0.0404 μg/Nm(3), respectively. The emission factor for PCDD/PCDF and HCB varied from 0.0137 to 0.0281 μg/ton and from 17.32 to 109.34 μg/ton of clinker, respectively. The concentration of PCDD/PCDFs and HCB in solid samples decreased as follows: cement kiln dust, 4.1-5 ng I-TEQ/kg and 0.70-0.71 μg/kg, respectively; >raw meal, 0.82-0.97 ng I-TEQ/kg and 0.18 μg/kg, respectively; >cement clinker, 0.09-0.22 ng I-TEQ/kg and 0.14-0.18 μg/kg, respectively. This study indicates that the feeding of DDT and POPs-wastes to the lower temperature part of a cement kiln system possibly to create a buildup of trace not-destroyed compounds in the system and might cause emissions; the technical feasibility and the environmental acceptability of this practice need to be investigated thoroughly. PMID:24468499

  10. DDE, DDT + dieldrin: Residues in American kestrels and relations to reproduction

    USGS Publications Warehouse

    Wiemeyer, Stanley N.; Porter, Ron; Hensler, G.L.; Maestrelli, J.R.

    1986-01-01

    Captive American kestrels (Falco sparverius) given long-term dietary dosages of DDT and dieldrin in combination, at low and high rates, were compared with controls to determine the effects of the toxicants on reproductive success and eggshell thickness. Additional kestrels were dosed with DDE to determine its effect on shell thickness. Tissues of birds that died or were sacrificed, and eggs, were analyzed for DDE, DDD, DDT, and dieldrin. Eight paired birds, mostly males, given a high dosage of DDT + dieldrin died of dieldrin poisoning. Three periods of heavy mortality involving only dosed birds, which occurred in summer 1966, fall 1967, and spring 1968, followed temperature declines and other stress factors. Organochlorine concentrations in tissues of sacrificed birds and eggs in all units of the DDT + dieldrin study were significantly different among treatments. Residue concentrations in tissues of birds on high dosage of DDT + dieldrin were about 3 times higher than those on low dosage, a difference similar to the relative magnitude of the dose rates. Concentrations of some toxicants, especially DDE, were significantly higher in tissues of males than females, although these differences were difficult to interpret because males generally were sacrificed later than females. Concentrations in tissues and eggs of dosed yearlings, placed on clean food 7 to 9 weeks before pairing, were often significantly lower than in those yearlings that remained on dosage. Concentrations of each toxicant were usually highly correlated (r > 0.85) among tissues, especially for DDE and dieldrin. Organochlorine concentrations in brains and eggs could be predicted from concentrations in carcasses. DDE and dieldrin concentrations in eggs were about one-half those in carcasses, DDD about one-seventh, and DDT 1.5 to 2 times higher in eggs than carcasses. Eggshells of DDT + dieldrin-dosed kestrels were 6-23% thinner than eggshells of corresponding controls in different groups and years

  11. Rapid separation of polychlorinated biphenyls from DDT and its analogues on silica gel

    USGS Publications Warehouse

    Snyder, Diane; Reinert, Robert E.

    1971-01-01

    Polychlorinated biphenyls (PCB's), which are used in industry worldwide (i), have been found as residues in numerous wildlife species (2-7). Because of the similarity in chemical characteristics, PCB compounds interfere with gas liquid chromatographic (GLC) analysis of certain chlorinated hydrocarbon insecticides (8). In the present study, we sought a rapid microanalytical procedure for separation of PCB's from DDT and its analogues before analysis with GLC. A small silica gel column was found to be suitable for removing two of the Aroclor series of PCB's (1254 and 1260) from DDT and its analogues.

  12. Fluid dynamics of the unsteady two phase processes leading to DDT in granular solid propellants

    NASA Technical Reports Server (NTRS)

    Krier, H.; Butler, P. B.; Lembeck, M. F.

    1980-01-01

    Deflagration to Detonation (DDT) was predicted to occur in porous beds of high-energy solid propellants by solving the unsteady fluid mechanical convective heat transfer from hot gas products, obtained from the rapid burning at high pressures, provides the impetus to develop a narrow combustion zone and a resulting strong shock. A parametric study clearly indicates that DDT occurs only when a combination of the solids loading fraction, the burning rate constants, the propellant chemical energy, and the particle size provide for critical energy and gas release to support a detonation wave. Predictions for the run-up length to detonation as a function of these parameters are presented.

  13. RNAi validation of resistance genes and their interactions in the highly DDT-resistant 91-R strain of Drosophila melanogaster.

    PubMed

    Gellatly, Kyle J; Yoon, Kyong Sup; Doherty, Jeffery J; Sun, Weilin; Pittendrigh, Barry R; Clark, J Marshall

    2015-06-01

    4,4'-dichlorodiphenyltrichloroethane (DDT) has been re-recommended by the World Health Organization for malaria mosquito control. Previous DDT use has resulted in resistance, and with continued use resistance will increase in terms of level and extent. Drosophila melanogaster is a model dipteran that has many available genetic tools, numerous studies done on insecticide resistance mechanisms, and is related to malaria mosquitoes allowing for extrapolation. The 91-R strain of D. melanogaster is highly resistant to DDT (>1500-fold), however, there is no mechanistic scheme that accounts for this level of resistance. Recently, reduced penetration, increased detoxification, and direct excretion have been identified as resistance mechanisms in the 91-R strain. Their interactions, however, remain unclear. Use of UAS-RNAi transgenic lines of D. melanogaster allowed for the targeted knockdown of genes putatively involved in DDT resistance and has validated the role of several cuticular proteins (Cyp4g1 and Lcp1), cytochrome P450 monooxygenases (Cyp6g1 and Cyp12d1), and ATP binding cassette transporters (Mdr50, Mdr65, and Mrp1) involved in DDT resistance. Further, increased sensitivity to DDT in the 91-R strain after intra-abdominal dsRNA injection for Mdr50, Mdr65, and Mrp1 was determined by a DDT contact bioassay, directly implicating these genes in DDT efflux and resistance. PMID:26047118

  14. Organochlorine pesticides and metabolites in young leaves of Mangifera indica from sites near a point source in Coast region, Tanzania.

    PubMed

    Marco, John A Mahugija; Kishimba, Michael A

    2007-06-01

    Young leaves of Mangifera indica (mango tree) from nine sites were used as bioindicators of local atmospheric contamination by organochlorine pesticides and metabolites from a point source, an old storage site at Vikuge farm in Tanzania. Sample extracts were analysed by GC-ECD and GC-MS. The concentrations ranged 2.7-649 ng g(-1)p,p'-DDT, below detection limit (bdl)-290 ng g(-1) o,p'-DDT, 0.4-13 ng g(-1) p,p'-DDE, bdl to 4 ng g(-1) o,p'-DDE, 1-231 ng g(-1) p,p'-DDD and 0.5-55 ng g(-1) o,p'-DDD. The concentrations of other compounds were up to 3.9 ng g(-1) pentachloroanisole, 1.3 ng g(-1) alpha-HCH, 12 ng g(-1) beta-HCH and 2 ng g(-1) gamma-HCH, on fresh weight basis. The compounds p,p'-DDT, p,p'-DDE, p,p'DDD and o,p'-DDD were found in 100% of the samples, while pentachloroanisole, o,p'-DDT and o,p'-DDE were detected in 78%, 56% and 67% of the samples, respectively. The low DDE/DDT ratios (0.01-0.20) in all samples indicate recent input of significantly non-degraded DDT from the point source. The low alpha-/gamma-HCH ratios (<0.3-0.7) in most samples indicate recent input of lindane (99% gamma-HCH). The slightly high alpha-/gamma-HCH ratios in some samples might be due to photochemical or bacterial transformation of gamma-HCH to alpha-HCH, or could reflect input of technical HCH. The very strong positive correlations in the concentrations of p,p'-DDT, p,p'-DDE, p,p'-DDD, o,p'-DDT, o,p'-DDE and o,p'-DDD (r=0.91-0.98, n=18, p<0.01) indicate that they have a common source. The results suggest that young mango leaves are suitable bioindicators of recent inputs of organochlorine contaminants from a point source. PMID:17395245

  15. PCBs have declined more than DDT-group residues in Arctic ringed seals (Phoca hispida) between 1972 and 1981

    SciTech Connect

    Addison, R.F.; Zinck, M.E.; Smith, T.G.

    1986-03-01

    Mean DDT-group concentrations in the blubber of western Arctic ringed seals (Phoca hispida) sampled in 1981 were less than 1..mu..g.g/sup -1/ wet weight. Male seals had higher concentrations than did females. PCB concentrations were about half of those in a sample of the same population taken in 1972, when allowance was made for the variation of residue concentrations with age, sex, and condition. This decline probably results from the ban on PCB manufacture and use imposed in the early 1970s. Concentrations of DDT-group residues did not show any clear decline over the same interval, and the relative proportions of p,p'-DDT and p,p'-DDE suggested that there is a continuing supply of DDT to the western Arctic. The most probable source of this is by atmospheric or water transport from the Far East, where DDT was used until at least the late 1970s.

  16. Impact of climate fluctuations on deposition of DDT and hexachlorocyclohexane in mountain glaciers: evidence from ice core records.

    PubMed

    Wang, Xiaoping; Gong, Ping; Zhang, Qianggong; Yao, Tandong

    2010-02-01

    How do climate fluctuations affect DDT and hexachlorocyclohexane (HCH) distribution in the global scale? In this study, the interactions between climate variations and depositions of DDT and HCH in ice cores from Mt. Everest (the Tibetan Plateau), Mt. Muztagata (the eastern Pamirs) and the Rocky Mountains were investigated. All data regarding DDT/HCH deposition were obtained from the published results. Concentrations of DDT and HCH in an ice core from Mt. Everest were associated with the El Nino-Southern Oscillation. Concentrations of DDT in an ice core from Mt. Muztagata were significantly correlated with the Siberia High pattern. Concentrations of HCH in an ice core from Snow Dome of the Rocky Mountains responded to the North Atlantic Oscillation. These associations suggested that there are some linkages between climate variations and the global distribution of persistent organic pollutants. PMID:19775787

  17. Efficient transformation of DDT by peroxymonosulfate activated with cobalt in aqueous systems: Kinetics, products, and reactive species identification.

    PubMed

    Qin, Wenxiu; Fang, Guodong; Wang, Yujun; Wu, Tongliang; Zhu, Changyin; Zhou, Dongmei

    2016-04-01

    Recently, sulfate radical ( [Formula: see text] ) based-advanced oxidation technologies (AOTs) have been attracted great attention in the remediation of contaminated soil and groundwater. In the present study, Co(2+) ions activated peroxymonosulfate (PMS) system was used to degrade 1, 1, 1-trichloro-2, 2'bis(p-chlorophenyl) ethane (DDT) in aqueous solutions. It was found that DDT was efficiently degraded in the PMS/Co(II) solutions within several hours, and the degradation efficiency of DDT was dependent on the concentrations of PMS and Co(II), and the optimum molar ratio of PMS and Co(II) was 50:1. The degradation kinetics of DDT were well described with pseudo-first-order equations over a range of temperature (10-40 °C), and the activation energy that was calculated with Arrhenius equation was 72.3 ± 2.6 kJ/mol. Electron paramagnetic resonance (EPR) and GC-MS techniques were applied to identify the intermediates and reactive species for DDT degradation. The results indicated that [Formula: see text] and OH were the main reactive species accounting for DDT degradation. Dichlorobenzophenone, 4-chlorobenzoic acid and benzylalcohol were the dominant intermediates for DDT degradation, and the likely degradation pathway of DDT was proposed on the basis of these identified products. Increasing pH inhibited the formation of [Formula: see text] and OH, and thus decreased the catalytic degradation of DDT. Cl(-) ion was found to significantly inhibit, while [Formula: see text] and dissolved oxygen had limited effects on DDT degradation. PMID:26802265

  18. Rapid determination of dichlorodiphenyltrichloroethane and its main metabolites in aqueous samples by one-step microwave-assisted headspace controlled-temperature liquid-phase microextraction and gas chromatography with electron capture detection.

    PubMed

    Vinoth Kumar, Ponnusamy; Jen, Jen-Fon

    2011-03-01

    A rapid and sensitive analytical method for the determination of dichlorodiphenyltrichloroethane (DDT) and its main metabolites in environmental aqueous samples has been developed using one-step microwave-assisted headspace controlled-temperature liquid-phase micro-extraction (MA-HS-CT-LPME) technique coupled with gas chromatography-electron-capture detection (GC-ECD). In this study, the one-step extraction of DDT and its main metabolites was achieved by using microwave heating to accelerate the evaporation of analytes into the controlled-temperature headspace to form a cloudy mist vapor zone for LPME sampling. Parameters influencing extraction efficiency were thoroughly optimized, and the best extraction for DDT and its main metabolites from 10-mL aqueous sample at pH 6.0 was achieved by using 1-octanol (4-μL) as the LPME solvent, sampling at 34°C for 6.5 min under 249W of microwave irradiation. Under optimum conditions, excellent linear relationship was obtained in the range of 0.05-1.0 μg/L for 1-dichloro-2,2-bis-(p'-chlorophenyl)ethylene (p,p'-DDE), 0.1-2.0 μg/L for o,p'-DDT, 0.15-3.0 μg/L for 1,1-dichloro-2,2-bis-(p'-chlorophenyl)ethane (p,p'-DDD) and p,p'-DDT, with detection limits of 20 ng/L for p,p'-DDE, and 30 ng/L for o,p'-DDT, p,p'-DDD and p,p'-DDT. Precision was in the range of 3.2-11.3% RSD. The proposed method was validated with environmental water samples. The spiked recovery was between 95.5% and 101.3% for agricultural-field water, between 94% and 99.7% for sea water and between 93.5% and 98% for river water. Thus the established method has been proved to be a simple, rapid, sensitive, inexpensive and eco-friendly procedure for the determination of DDT and its main metabolites in environmental water samples. PMID:21251695

  19. Concentrations of DDT, PVBs, HCB, and HCH isomers in the liver and adipose tissue of newborn mice receiving an extract of human milk

    SciTech Connect

    Sitarska, E.; Gorski, T.; Ludwick, J.K.

    1987-11-01

    Persistent organic chlorine compounds, such as DDT and its metabolites, hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs) circulate in the food chain of the ecosystem. Most data on the toxicity and accumulation of organic chlorine compounds have been obtained from animal experiments after chronic or acute poisoning with marketed preparations or standards of the used components of these preparations. In food products of animal origin and in human milk these compounds and their metabolites are present after multiple metabolic steps in varying proportions and concentrations. Their variable amounts are passed to newborns with mother's milk. The purpose of the present study was to investigate in an experimental model of newborn mice the degree of accumulation of these compounds in the liver and adipose tissue after long-standing feeding them with an extract of human milk with added organic chlorine compounds in doses received by human newborns with milk. In the assessment of the relationship between the degree of accumulation of various compounds in the tissues of newborn mice and the daily dose concentrations were used similar to those found in human milk.

  20. OPTICAL IMMUNOSENCOR AND CONVENTIONAL ELISA FOR THE ANALYSIS OF PYRETHROIDS AND DDT IN ENVIRONMENTAL SAMPLES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An optical immunosensor (AQUA-OPTOSENSOR) and conventional ELISA (enzyme-linked immunosorbent assay)for the analysis of pyrethroids and DDT in environmental samples, namely river water and/or sediment, are described. The optical immunosensor consists of a bench-top optical read-out-device and dispos...

  1. Studies of DDT enhancement approaches for kerosene-fueled small-scale pulse detonation engines applications

    NASA Astrophysics Data System (ADS)

    Huang, Y.; Tang, H.; Li, J.; Zhang, C.

    2012-11-01

    Two-phase small-scale pulse detonation engine (SPDE) offers a competitive alternative for small-scale propulsion systems from a high cycle efficiency and structural simplicity standpoint. SPDE models are designed with the aero-valve, and three different cases of obstacle combinations are used as deflagration-to-detonation transition (DDT) devices. The inner diameters of detonation tubes are 29 mm, and the lengths of three SPDEs are 995, 1,100, and 1,175 mm. Using kerosene-air as the fuel-oxidizer, a series of high-frequency detonation tests is conducted to seek efficient DDT enhancement approaches that reduce DDT distance and time and increase the frequency of kerosene-fueled SPDE. The results show that the fully developed detonation wave can be achieved at a distance of 3.4 times the minimum characteristic distance for gaseous detonation formation from the igniter and that the SPDE can steadily operate at a maximal frequency of 62.5 Hz. By adopting these DDT enhancement approaches, the detonability of kerosene is significantly improved. In addition, experiments are performed to study the effects of firing frequencies on detonation transitions. The results clearly indicate that the values of detonation wave pressures and velocities, the degree of overdriven wave, the ignition delay times, and detonation initiation times vary with frequencies. In terms of the performance, the optimal frequencies of three SPDE models are 20, 42.5, and 50 Hz, respectively.

  2. [Using instantaneous spectra to determine dominant species in the DDT process of epoxypropane].

    PubMed

    Li, Ping; Hu, Dong; Yuan, Chang-Ying; Dai, Song-Hui; Xiao, Hai-Bo

    2006-09-01

    After solving problems of weak light detection, the calibration of the spectral sensitivity of the measuring system, and the synchronization of the measuring system, instantaneous emission spectra of epoxypropane in the process of deflagration to detonation transition (DDT) with the exposure time of 2-8 micros and the resolution of 0. 2 nm were acquired from six different side windows of an explosion shock tube. Using the corrected spectral data, curves of the optical radiant intensity of main reaction products versus the DDT distance from the ignition point were obtained. These curves provided information about the evolution of the reaction and the products during the DDT process. Results indicate that the chemical reaction rate of the gaseous fuel and the corresponding concentrations of intermediate products increased gradually at the deflagration stage, but at the moment of deflagration to detonation transition, the reaction rate increased rapidly and the concentrations! of products increased sharply. Among these main products, concentration increments of molecule CO, and radicals CHO and OH were greater than other products, which means that CO, CHO and OH are the dominant species that affect the DDT process greatly. PMID:17112018

  3. Effects of dressing and cooking on DDT concentrations in certain fish from Lake Michigan

    USGS Publications Warehouse

    Reinert, Robert E.; Stewart, Donald; Seagran, Harry L.

    1972-01-01

    Concentrations of DDT residues were highest in parts of the body with the highest oil content in four species of fish from Lake Michigan: yellow perch (Perca flavescens), bloater (Coregonus hoyi), lake trout (Salvelinus namaycush), and coho salmon (Oncorhynchus kisutch). Dressing reduced the DDT residues and oil content by more than 90% in yellow perch but had little effect in the other three species. The concentration of DDT residues in bloaters was changed little by smoking but was reduced 64–72% by other methods of cooking: from 8.0 ppm (raw) to 2.2 ppm after frying in corn oil; from 10.7 to 3.9 ppm after frying in lard; and from 9.1 to 3.2 ppm after broiling. The concentration of DDT residues in fillets of yellow perch changed only from 0.3 ppm (raw) to 0.4 or 0.5 ppm after baking, frying, or broiling.

  4. [Indoor and outdoor nebulization of DDT in the campaign against cutaneous zoonotic leishmaniasis in Algeria].

    PubMed

    Benzerroug, E H; Benhabylles, N; Izri, M A; Belahcene, E K

    1992-03-01

    Zoonotic cutaneous leishmaniasis is expanding in certain regions of Algeria. Since 1981, when the disease was confined to the foci of Biskra and Abadla, it spread to the neighbouring departments (wilayas) and especially to the wilaya of M'sila. The authors report the results of a large campaign against the disease, using DDT house spraying, in this wilaya. The annual incidence, which was 426 cases per 100,000 inhabitants in January 1983, dropped to 17.9 in January 1984. In addition, the efficacy of DDT in the reduction of the sandfly population was tested in two localities. One was sprayed with DDT and the other was not. In the sprayed locality the sandfly population decreased markedly as compared to the control locality. From these observations the authors believe that DDT plays a major role in the interruption of transmission, a hypothesis which needs to be confirmed by case-control studies. They further recommend that an interdisciplinary approach should be developed for the control of cutaneous leishmaniasis. PMID:1567269

  5. ASSESSING POTENTIAL UPTAKE OF DDT, DDE, AND DDD ISOMERS FROM SOIL BY A ROOT CROP

    EPA Science Inventory

    Radishes were grown from seed in DDT contaminated soils and a potting mix control at the Soil Physics and Pesticide Research Unit of the USDA Agriculture Research Service Laboratory in Riverside, CA. Plants were irrigated daily allowing little leaching, fertilized as needed, and...

  6. Assessing bioavailability and toxicity of permethrin and DDT in sediment using matrix solid phase microextraction.

    PubMed

    Ding, Yuping; Landrum, Peter F; You, Jing; Lydy, Michael J

    2013-01-01

    Matrix solid phase microextraction (matrix-SPME) was evaluated as a surrogate for the absorbed dose in organisms to estimate bioavailability and toxicity of permethrin and dichlorodiphenyltrichloroethane (DDT) in laboratory-spiked sediment. Sediments were incubated for 7, 28, and 90 days at room temperature to characterize the effect of aging on bioavailability and toxicity. Sediment toxicity was assessed using two freshwater invertebrates, the midge Chironomus dilutus and amphipod Hyalella azteca. Disposable polydimethylsiloxane fibers were used to estimate the absorbed dose in organisms and to examine bioavailability and toxicity. The equilibrium fiber concentrations substantially decreased with an increase in sediment aging time, indicating a reduction in bioavailability. Based on median lethal fiber concentrations (fiber LC50), toxicity of permethrin was not significantly different among the different aging times. Due to the substantial degradation of DDT to dichlorodiphenyldichloroethane (DDD) in sediment, sediment toxicity to C. dilutus increased, while it decreased for H. azteca with extended aging times. A toxic unit-based fiber LC50 value represented the DDT mixture (DDT and DDD) toxicity for both species. Significant linear relationships were found between organism body residues and the equilibrium fiber concentrations for each compound, across aging times. The study suggested that the matrix-SPME fibers mimicked bioaccumulation in the organisms, and enabled estimation of body residues, and could potentially be used in environmental risk assessment across matrices (e.g. sediment and water) to measure bioavailability and toxicity of hydrophobic pesticides. PMID:23086182

  7. Pyrethroid and DDT Resistance and Organophosphate Susceptibility among Anopheles spp. Mosquitoes, Western Kenya

    PubMed Central

    Wanjala, Christine L.; Mbugi, Jernard P.; Ototo, Edna; Gesuge, Maxwell; Afrane, Yaw A.; Atieli, Harrysone E.; Zhou, Guofa; Githeko, Andrew K.

    2015-01-01

    We conducted standard insecticide susceptibility testing across western Kenya and found that the Anopheles gambiae mosquito has acquired high resistance to pyrethroids and DDT, patchy resistance to carbamates, but no resistance to organophosphates. Use of non–pyrethroid-based vector control tools may be preferable for malaria prevention in this region. PMID:26583525

  8. Pyrethroid and DDT Resistance and Organophosphate Susceptibility among Anopheles spp. Mosquitoes, Western Kenya.

    PubMed

    Wanjala, Christine L; Mbugi, Jernard P; Ototo, Edna; Gesuge, Maxwell; Afrane, Yaw A; Atieli, Harrysone E; Zhou, Guofa; Githeko, Andrew K; Yan, Guiyun

    2015-12-01

    We conducted standard insecticide susceptibility testing across western Kenya and found that the Anopheles gambiae mosquito has acquired high resistance to pyrethroids and DDT, patchy resistance to carbamates, but no resistance to organophosphates. Use of non-pyrethroid-based vector control tools may be preferable for malaria prevention in this region. PMID:26583525

  9. Characterisation of DDT and pyrethroid resistance in Trinidad and Tobago populations of Aedes aegypti.

    PubMed

    Polson, K A; Rawlins, S C; Brogdon, W G; Chadee, D D

    2011-08-01

    Insecticide resistance is an important factor in the effectiveness of Aedes aegypti control and the related spread of dengue. The objectives of this study were to investigate the status of the organochlorine dichlorodiphenyltrichloroethane (DDT) and pyrethroid (permethrin and deltamethrin) resistance in Trinidad and Tobago populations of Ae. aegypti and the underlying biochemical mechanisms. Nine populations of Ae. aegypti larvae from Trinidad and Tobago were assayed to DDT and PYs using the Centers for Disease Control and Prevention (CDC) time-mortality-based bioassay method. A diagnostic dosage (DD) was established for each insecticide using the CAREC reference susceptible Ae. aegypti strain and a resistance threshold (RT), time in which 98-100% mortality was observed in the CAREC strain, was calculated for each insecticide. Mosquitoes which survived the DD and RT were considered as resistant, and the resistance status of each population was categorised based on the WHO criteria with mortality <80% indicative of resistance. Biochemical assays were conducted to determine the activities of α and β esterases, mixed function oxidases (MFO) and glutathione-S-transferases (GST) enzymes which are involved in resistance of mosquitoes to DDT and PYs. Enzymatic activity levels in each population were compared with those obtained for the CAREC susceptible strain, and significant differences were determined by Kruskal-Wallis and Tukey's non-parametric tests (P<0.05). The established DDs were 0.01 mg l(-1), 0.2 mg l(-1) and 1.0 mg l(-1) for deltamethrin, permethrin and DDT, respectively; and the RTs for deltamethrin, permethrin and DDT were 30, 75 and 120 min, respectively. All Ae. aegypti populations were resistant to DDT (<80% mortality); two strains were incipiently resistant to deltamethrin and three to permethrin (80-98% mortality). Biochemical assays revealed elevated levels of α-esterase and MFO enzymes in all Ae. aegypti populations. All, except three populations

  10. Enhanced metabolite generation

    DOEpatents

    Chidambaram, Devicharan

    2012-03-27

    The present invention relates to the enhanced production of metabolites by a process whereby a carbon source is oxidized with a fermentative microbe in a compartment having a portal. An electron acceptor is added to the compartment to assist the microbe in the removal of excess electrons. The electron acceptor accepts electrons from the microbe after oxidation of the carbon source. Other transfers of electrons can take place to enhance the production of the metabolite, such as acids, biofuels or brewed beverages.

  11. Occurrence and distribution of organochlorine pesticides (HCH and DDT) in sediments collected from East China Sea.

    PubMed

    Yang, Rui-qiang; Jiang, Gui-bin; Zhou, Qun-fang; Yuan, Chun-gang; Shi, Jian-bo

    2005-08-01

    Sediments used in this study were collected from different depths of eight sites in East China Sea in November 2002. The levels and distribution patterns of the selected organochlorine pesticides (OCPs=p,p'-DDT, o,p'-DDT, p,p'-DDE, p,p'-DDD, alpha-, beta-, gamma- and delta-HCH) in samples were investigated by the technique of sonication extraction followed by the analysis of gas chromatography (GC) coupled with a micro-electron capture detector (muECD). The concentrations of SigmaHCH and SigmaDDT in the surface sediments were in the range of <0.05-1.45 ng/g (mean 0.76 ng/g), <0.06-6.04 ng/g (mean 3.05 ng/g) based on dry weight (dw), respectively. In the vertical distributions, the SigmaHCH and SigmaDDT were in the range of <0.05-2.52 ng/g, <0.06-10.94 ng/g dw, respectively. Residues of OCPs varied significantly with different sampling sites. SigmaDDT in the surface sediments was correlated well with total organic carbon (TOC) content (r2=0.71), while SigmaHCH showed no obvious correlation. The distribution showed that the sediments from the vicinity estuary or near shore had higher TOC contents, and higher OCPs concentrations. The contamination record indicated an extensive use of OCPs in the catchments from Yangtze River in the past might greatly affect the OCP residues. PMID:16024080

  12. [Effect of surfactant on sorption behaviors of DDT on Jiaozhou Bay sediment].

    PubMed

    Cao, Xiao-Yan; Jing, Jian-Ning; Yang, Gui-Peng; Gong, Xiao-Fei

    2011-11-01

    A batch sorption study was carried out to investigate the sorption behaviors of DDT onto JiaoZhou Bay sediment in the presence of an anionic surfactant sodium dodecylbenzene sulfonate (SDBS), and a cationic surfactant, cetyltrimethylammonium bromide (CTAB) with low concentrations. The results indicated that the sorption process followed the pseudo-second-order model and the sorption systems could be well described by the Freundlich type. Within the investigated concentrations of CTAB and SDBS, both SDBS and CTAB increased the sorption of DDT to sediment. The sorption rate and capacity increased with increasing SDBS and CTAB concentrations, and CTAB showed a significant impact. Take p ,p'-DDT as an example, the sorption rate constant increased from 1.232 x 10(-2) g x (microg x min)(-1) to 4.193 x 10(-2) g x (microg x min)(-1) and the Freundlich coefficient increased from 2.866 (microg x g(-1)) (L x microg(-1))(1/n) to 7.932 (microg x g(-1)) (L x microg(-1))(1/n) when the SDBS concentration was 10 mg x L(-1). The influence of temperature on sorption of DDT in the presence of SDBS was also studied. Within the temperature range of 283-308 K, lower temperature had a positive effect on the sorption. The thermodynamic parameters showed that the sorption was spontaneous and exothermic, and the randomness was increased during the process. Furthermore, the presence of SDBS caused lower deltaG0, deltaH0 and deltaS0 values. This study provided theoretical foundation for migration, transformation and fate of DDT in Jiaozhou Bay sediment. PMID:22295631

  13. Targeting distinct tautomerase sites of D-DT and MIF with a single molecule for inhibition of neutrophil lung recruitment

    PubMed Central

    Rajasekaran, Deepa; Zierow, Swen; Syed, Mansoor; Bucala, Richard; Bhandari, Vineet; Lolis, Elias J.

    2014-01-01

    We report a new inflammatory activity for extracellular d-dopachrome tautomerase (D-DT), the recruitment of neutrophils to the lung on D-DT intratracheal installation of C57BL/6J mice with an EC50 of 5.6 μg. We also find that D-DT and macrophage migration inhibitory factor (MIF) have additive effects in neutrophil recruitment. Although the tautomerase site of D-DT and its homologue MIF are biophysically very different, 4-iodo-6-phenylpyrimidine (4-IPP) forms a covalent bond with Pro-1 of both proteins, resulting in a 6-phenylpyrimidine (6-PP) adduct. Recruitment of neutrophils to the lung for the 6-PP adducts of D-DT and MIF are reduced by ∼50% relative to the apo proteins, demonstrating that an unmodified Pro-1 is important for this activity, but there is no cooperativity in inhibition of the proteins together. The differences in the binding mode of the 6-PP adduct for D-DT was determined by crystallographic studies at 1.13 Å resolution and compared to the structure of the MIF–6-PP complex. There are major differences in the location of the 6-PP adduct to the D-DT and MIF active sites that provide insight into the lack of cooperativity by 4-IPP and into tuning the properties of the covalent inhibitors of D-DT and MIF that are necessary for the development of therapeutic small molecules against neutrophil damage from lung infections such as Pseudomonas aeruginosa in cystic fibrosis and immunocompromised patients.—Rajasekaran, D., Zierow, S., Syed, M., Bucala, R., Bhandari, V., Lolis, E. J. Targeting distinct tautomerase sites of D-DT and MIF with a single molecule for inhibition of neutrophil lung recruitment. PMID:25016026

  14. Magnetic nanoparticles of nitrogen enriched carbon (mnNEC) for analysis of pesticides and metabolites in zebrafish by gas chromatography-mass spectrometry.

    PubMed

    Zhou, Youe; Xia, Qian; Ding, Mengjie; Kageruka, Hubert; Jiang, Haiying; Jiang, Yan; Jing, Huifen; Xiao, Xiao; Zhong, Hongying

    2013-02-01

    Nanosized carbon based sorbents have been widely used for separation, enrichment and desalting of biological samples because of their distinguished characteristics. In this work, magnetic nanoparticles of nitrogen enriched carbon (mnNEC) have been developed for enrichment of organochlorine pesticide DDT and metabolite DDE that have been accumulated in zebrafish during the course of environmental exposure. Polymerization of pyrrole was performed in the aqueous suspension of Fe(3)O(4) nanoparticles. Resultant core-shell nanoparticules coated with polypyrrole were then subjected to a process of carbonization under high temperature and nitrogen atmospheric condition. The presence of nitrogen atoms in carbon nanoparticles increases the hydrophilicity and dispersability in aqueous samples. It has been experimentally demonstrated that mnNEC can be effectively dispersed in aqueous samples and rapidly isolated by the application of an external magnetic field. Recoveries of DDT and DDE from water range from 90% to 102% and 85-97% respectively. In combination with Selected Ion Monitoring (SIM) experiments of gas chromatography-mass spectrometry, the detection limit can be down to low ng/mL level. By using mnNEC approach, two interesting results have been found for zebrafish with 60 days exposure to DDT (1 μg/l). (1) There is higher concentration of DDT (37-143 ng/g) and DDE (173-1108 ng/g) in male zebrafish body tissues than that of female (7-52 ng/g and 146-362 ng/g for DDT and DDE respectively). (2) There is high ratio of DDE/DDT for both female and male zebrafish, implying high environmental persistence and ongoing bioaccumulation. PMID:23328251

  15. [Alteration of thyroid hormone secretion after long-term exposure to low doses of endocrine disruptor DDT].

    PubMed

    Iaglova, N V; Iaglov, V V

    2014-01-01

    Endocrine disruptors are exogenous substances that exhibit hormone-like action and consequently disrupt homeostatic action of endogenous hormones. DDT is the most common disruptor. The objective was to evaluate changes in thyroid hormone secretion after long-term exposure to low doses of DDT. The experiment was performed on male Wistar rats. The rats were given DDT at doses of 1.89±0.86 мg/kg/day and 7.77±0.17 мg/kg/day for 6 and 10 weeks. Dose dependent increase of serum total thyroxine, total triiodthyronine, and thyroid peroxidase was revealed after 6 weeks exposure. After 10 weeks free thyroxine secretion was reduced. Such alterations of the thyroid status are typical for iodine deficient goiter. The data obtained indicate that the main mechanism of DDT action includes disruption of thyroxine secretion by thyrocytes, but not inhibition of deiodinase activity and decrease of blood thyroid binding proteins. PMID:25552505

  16. Enantioselective induction of cytotoxicity by o,p'-DDD in PC12 cells: implications of chirality in risk assessment of POPs metabolites.

    PubMed

    Wang, Cui; Li, Zhuoyu; Zhang, Quan; Zhao, Meirong; Liu, Weiping

    2013-04-16

    The increased release of chiral persistent organic pollutants (POPs) into the environment has resulted in more attention to the role of enantioselectivity in the fate and ecotoxicological effects of these compounds. Although the enantioselectivity of chiral POPs has been considered in previous studies, little effort has been expended to discern the enantiospecific effects of chiral POPs metabolites, which may impede comprehensive risk assessments of these chemicals. In the present study, o,p'-DDD, the chiral metabolite of o,p'-DDT, was used as a model chiral metabolite. First, a preferential chiral separation at 100% ethanol was employed to obtain a pure enantiomer. The enantioselective cytotoxicity of o,p'-DDD in rat cells (PC12) was evaluated by detecting activation of the cellular apoptosis and oxidative stress systems and microarray analysis. We have documented for the first time that R-(+)-o,p'-DDD increases apoptosis by selectively disturbing the oxidative system (enzymes and molecules) and regulating the transcription of Aven, Bid, Cideb and Tp53. By comparing the data from the present study to data derived from the parent compound, we concluded that the R-enantiomer is the more detrimental stereostructure for both o,p'-DDT and o,p'-DDD. This observed stereostructural effect is in line with the structure-activity relationship formulated at other structural levels. Biological activities of the chiral metabolites are likely to occur in the same absolute configuration between chiral POPs and their metabolites provided that they have the similar stereostructures. PMID:23485034

  17. DDT and HCH isomer levels in soils, carrot root and carrot leaf samples.

    PubMed

    Waliszewski, S M; Carvajal, O; Gómez-Arroyo, S; Amador-Muñoz, O; Villalobos-Pietrini, R; Hayward-Jones, P M; Valencia-Quintana, R

    2008-10-01

    Agricultural cultivation assists organochlorine pesticide migration from contaminated soils to growing plants. This phenomenon is caused by retention processes that modify volatile pesticide exchange between soil, air and plants. The aim of the study was to monitor organochlorine pesticide (HCB, alpha- and gamma-HCH, pp'DDE, op'DDT, pp'DDT) levels and compare these concentrations in soil, carrot roots and carrot leaves. Fifty soil samples, 50 carrot root and 50 carrot leaf samples were taken from the same fields and analyzed by GLC-ECD. The results reveal organochlorine pesticide diffusion from agricultural soils to growing carrot plants and their vapors adsorption by leaves. Within the carrot plant, organochlorine pesticides accumulate especially in carrot root peel, 3-7 times more than in root flesh. PMID:18626561

  18. Dissipation of DDT in a heavily contaminated soil in Mato Grosso, Brazil.

    PubMed

    Dalla Villa, Ricardo; de Carvalho Dores, Eliana Freire Gaspar; Carbo, Leandro; Cunha, Marcelo Luiz Ferreira

    2006-07-01

    After the prohibition of organochlorine-pesticide use in Brazil for controlling insect vector diseases, Mato Grosso State gathered the exceeding DDT and stored it irregularly in an open air area that belongs to the National Health Foundation, causing soil contamination. This study aimed to evaluate the contamination level and dissipation of p,p'-DDT and p,p'-DDE in this area. For that, surface soil samples were collected on 19 September 2000, 15 December 2000, 4 April 2001 and soil samples 30-40 cm; 60-70 cm and 90-100 cm deep were taken from five points in the studied area on 17 July 2001. The contaminants were determined by a small scale method which consists on extraction and clean-up steps combined into one step by transferring soil samples mixed with neutral alumina to a chromatographic column prepacked with neutral alumina and elution with hexane:dichloromethane (7:3 v:v). The eluate was concentrated and the analytes were quantified by gas chromatography with an electron-capture detector. p,p'-DDT at surface soil ranged from 3,800 to 7,300 mg kg(-1). 30-40 cm deep soil sample concentrations varied from 0.036 to 440 mg kg(-1) while 90-100 cm deep samples varied from 0.069 to 180 mg kg(-1). Volatilization is probably the main dissipation process. The p,p'-DDT is moving slowly downward in the soil profile, however, the levels of this contaminant are high enough to present risk to underground waters. PMID:16442143

  19. DDE residues in young wood ducks (Aix sponsa) near a former DDT manufacturing plant

    USGS Publications Warehouse

    Fleming, W.J.; Cromartie, E.

    1981-01-01

    Breast muscle DDE residues were as high as 5.8 ppm wet-weight basis and 280 ppm lipid-weight basis in young wood ducks (Aix Sponsa) collected on Wheeler National Wildlife Refuge near a former DDT manufacturing plant in northern Alabama. The average DDE residue in wood ducks collected nearest the plant was 46 times background levels 74 km from the plant.

  20. A report on the deflagration-to-detonation transition (DDT) in the high explosive LX-04

    SciTech Connect

    Hare, D E; Forbes, J W; Garcia, F; Granholm, R H; Tarver, C M; Vandersall, K S; Sandusky, H W

    2004-06-30

    The deflagration-to-detonation transition (DDT) was investigated for 1.874 g/cc (98.8 % of theoretical maximum density) LX-04 in moderate confinement (4340 steel tube at R{sub C} 32 with 1.020 inch inside diameter and 0.235 inch thick wall) at both ambient initial temperature (roughly 20 C) and at an initial temperature of 186 C. No transition to detonation was observed in a 295 mm column length for either case.

  1. Violent Reactions and DDT in Hot, Thermally Damaged HMX-Based PBXs

    SciTech Connect

    Parker, Gary R. Jr.; Holmes, Matthew D.; Dickson, Peter; Asay, Blaine W.; McAfee, John M.

    2012-07-03

    Conventional high explosives (e.g. PBX 9501, LX-07) have been observed to react violently following thermal insult: (1) Fast convective and compressive burns (HEVR); (2) Thermal explosions (HEVR); and (3) Deflagration-to-detonation transition (DDT). No models exist that sufficiently capture/predict these complex multiphase and multiscale behaviors. For now, research is focused on identifying vulnerabilities and factors that control this behavior.

  2. Residues in common flicker and mountain bluebird eggs one year after a DDT application

    USGS Publications Warehouse

    Henny, C.J.; Olson, R.A.; Meeker, D.L.

    1977-01-01

    Common flicker (Colaptes auratus) and mountain bluebird (Sialia currucoides) eggs were examined 1 year after DDT application and showed a marked difference. Residue levels in mountain bluebird eggs were approximately 10 times higher than in common flicker eggs (5.29 to 0.58 ppm wet weight). These differences can be explained by disparate dietary habits. The mean level in American kestrel (Falco sparverius) eggs collected in the spray area at the same time was 6.42 ppm wet weight.

  3. Differential resistance of insect sodium channels with kdr mutations to deltamethrin, permethrin and DDT.

    PubMed

    Burton, Mark J; Mellor, Ian R; Duce, Ian R; Davies, T G Emyr; Field, Linda M; Williamson, Martin S

    2011-09-01

    Knockdown resistance (kdr) in insects, caused by inherited nucleotide polymorphisms in the voltage-gated sodium channel (VGSC) gene, is a major threat to the efficacy of pyrethroid insecticides. Classic kdr, resulting from an L1014F substitution in the VGSC is now present in numerous pest species. Two other substitutions at the L1014 locus have also been reported, L1014S and L1014H. Here we have used expression of L1014 modified Drosophila para VGSCs in Xenopus oocytes with two-electrode voltage clamp to characterise all three mutations. The mutations L1014F and L1014H caused significant depolarizing shifts in the half activation voltage (V(50,act)) from -17.3 mV (wild-type) to -13.1 and -13.5 mV respectively, whereas L1014S caused no shift in V(50,act) but its currents decayed significantly faster than wild-type channels. Treatment of the wild-type channel with deltamethrin (≥ 1 nM), permethrin (≥ 30 nM) or DDT (≥ 1 μM) resulted in hyperpolarizing shifts in V(50,act). Deltamethrin, permethrin and DDT also produced "tail currents" with EC₅₀s of 0.043, 0.40 and 65 μM and maximum modifications of 837, 325 and 7% respectively. L1014F provided a high level of resistance against all insecticides for both measured parameters. L1014H most effectively combated deltamethrin induced tail currents while L1014S strongly resisted the large DDT induced shifts in V(50,act). We conclude that L1014H and L1014S may have arisen through heavy exposure to specific pyrethroids and DDT respectively. PMID:21640822

  4. Toxicity of DDT to Japanese quail as influenced by body weight, breeding condition, and sex

    USGS Publications Warehouse

    Gish, C.D.; Chura, N.J.

    1970-01-01

    Controlled experiments were utilized to simulate the stresses on wild birds of breeding condition and of weight loss due to migration. Light conditions in the laboratory were manipulated to produce Japanese quail (Coturnix coturnix japonica) in breeding condition and not in breeding condition. Within each of these groups, some birds were partially starved before dosage and some were fully fed. Birds were then fed dietary levels of 0, 700, 922, 1214, or 1600 ppm dry weight of p,p?-DDT for a period of 20 days or until death. Birds partially starved before dosage were more susceptible to DDT intoxication than nonstarved ones, and birds not in breeding condition were slightly more so than birds in breeding condition. Similarly, males died earlier than females, and the birds of the lighter weight strain used in the second half of the study died earlier than the birds of the heavier strain used in the first half. The heavier birds of each sex not only survived longer than lighter individuals receiving the same treatments, but they also lost a greater proportion of their weight before death. During the early portion of the dosage period, females in breeding condition were less sensitive to DDT than were females not in breeding condition and males. After 10 days on dosage, however, the cumulative mortality of females in breeding condition rapidly approached that of males and of females not in breeding condition. Food restriction prior to dosage, strains of quail, breeding conditions, and sexes resulted in weight differences and a corresponding accentuation or delay of the effects of the different levels of DDT.

  5. Studies on Dechlorination of DDT with Alkaline 2-propanol and Iron-Nickel (Fe-Ni) Catalyst.

    NASA Astrophysics Data System (ADS)

    Shareef, A.; Zaman, S. U.

    2009-05-01

    The Persistent Organic Pollutants (POPs) pesticides were previously extensively used in the cotton production and other agricultural activities in Pakistan and at least three thousand metric tons of obsolete pesticides have been stored under extreme hazardous conditions in more than thousand sites. Locally banned or severely restricted pesticides are easily available and DDT is continuously illegally imported and use in our country. Elimination of organochlorine pesticides (OCPs) waste has received considerable attention over the past two decades. Existing catalytic hydrodechlorinated techniques for disposing of OCPs are very costly due to the use of noble metals as catalysts. The aim of our study is to develop the cost effective and efficient method for the safe disposal of OCPs. This study is in continuation work on dechlorination of organochlorine pesticides with Fe-Ni catalyst in alkaline 2-propanol media. We turned our attention to the development of DDT disposal method for the third world countries. Herein, we report our first finding that in alkaline 2-propanol with Fe-Ni catalyst is an effective method for dechlorination of DDT. Catalytic dechlorination of DDT was carried out in an alkaline solution of NaOH and 2-propanol in the presence of catalyst at the temperature below 82 oC and end products were analyzed by using Gas Chromatography (GC-ECD) and Ion Chromatography (IC) techniques. Results obtained with initial concentration of DDT ranging between 10-100 μg/ml showed conversion of DDT to chlorine free product within 4 hrs.

  6. Simultaneous presence of DDT and pyrethroid residues in human breast milk from a malaria endemic area in South Africa.

    PubMed

    Bouwman, H; Sereda, B; Meinhardt, H M

    2006-12-01

    DDT and pyrethroids were determined in 152 breast-milk samples from three towns in KwaZulu-Natal, South Africa, one of which had no need for DDT for malaria control. All compounds were found present in breast milk. Primiparae from one town had the highest mean SigmaDDT whole milk levels (238.23 microg/l), and multiparae from the same town had the highest means for permethrin (14.51 microg/l), cyfluthrin (41.74 microg/l), cypermethrin (4.24 microg/l), deltamethrin (8.39 microg/l), and Sigmapyrethroid (31.5 microg/l), most likely derived from agriculture. The ADI for DDT was only exceeded by infants from one town, but the ADI for pyrethroids was not exceeded. Since the ADI for DDT was recently reduced from 20 to 10 microg/kg/bw, we suggest that this aspect be treated with concern. We therefore raise a concern based on toxicant interactions, due to the presence of four different pyrethroids and DDT. Breastfeeding however, remains safe under prevailing conditions. PMID:16564119

  7. Long-term trends in DDT, PCBs, and chlordane in mussels from California

    SciTech Connect

    Stephenson, M.D.; Tjeerdema, R.S.

    1994-12-31

    Many contaminant programs have been established to study the geographical distributions and long-term trends of potential pollutants, but unfortunately, many have been short-lived because of economic cutbacks, providing limited information on long-term trends. The California State Mussel Watch program, however, has been continuously funded for the past 15 years. Several sites have been evaluated and were sampled often enough to obtain statistical resolution. Chlordane was evaluated at 29 stations, with 48% showing significant decreases over time; DDT was evaluated at 35 sites, with 43% showing significant declines; and PCBs were evaluated at 47 sites, with 21% showing significant drops over time. Both DDT and PCBs showed declines, corresponding to decreases in their concentrations in the effluent, at sites located in the vicinity of the Los Angeles County municipal sewage outfall. This long-term investigation indicates that, contrary to public opinion, the banning of DDT, chlordane, and PCBs by the USEPA has led to overall improvement in water quality.

  8. Analysis of Compaction Shock Interactions During DDT of Low Density HMX

    NASA Astrophysics Data System (ADS)

    Rao, Pratap; Gonthier, Keith

    2015-06-01

    Deflagration-to-Detonation Transition (DDT) within low density HMX often occurs by a complex mechanism that involves compaction shock interactions. Piston driven DDT experiments indicate that detonation can be abruptly triggered by the interaction of a strong combustion driven shock and a lead piston supported shock, where the nature of the interaction depends on initial density and lead shock strength. These shocks induce dissipation and thermomechanical fluctuations at the meso-scale due to pore collapse resulting in hot-spots. Inert meso-scale simulations of successive shock loading of low density HMX are performed to examine how dissipation and hot-spot formation are affected by initial density, and lead and trailing shock strength. Emphasis is placed on interpreting solutions in a phase space expressed in terms of effective pressure and dissipative work because of their relevance to hot-spot formation. Meso-scale predictions are shown to compare favorably to those given by a macro-scale theory. This information is being used to formulate a dissipation-dependent reactive burn model to describe shock desensitization and DDT. Preliminary redictions will be presented that illustrate how initial density and input shock strength can affect the transition mechanism. This research is supported by the Defense Threat Reduction Agency (DTRA) under sponsor Award Number HDTRA1-10-1-0018, and the Air Force Research Laboratory (AFRL-RWME) under sponsor Award Number FA8651-09-0021.

  9. DDT in Mytilus edulis: Spatio-temporal variations in the Punta Banda estuary, Baja California, Mexico

    SciTech Connect

    Galindo-Bect, M.S.; Flores-Baez, B.P. )

    1991-02-01

    The mussel Mytilus sp. has been widely used as a sentinel organism or biological indicator of organic pollutants in the marine environment. In studies recently carried out in Baja California, Mexico, it was found that the spatial and temporal variations of DDT in samples of the mussel Mytilus californianus collected from the area exposed to the ocean do not follow a defined pattern and that the highest values of DDT are found at the border with the US. The Maneadero Valley in Baja California, Mexico, is an agricultural area where important volumes of pesticides are applied, part of which are transported to the Punta Banda Estuary where they remain for an undetermined period of time during which they are consumed and bioaccumulated by organisms. The main objective of the present work is to determine the levels and temporal variation of DDT in the mussel Mytilus edulis in the Punta Banda Estuary, Baja California. With the results, the authors will define the dynamics of this pollutant in the estuary.

  10. The effects of DDT upon the survival and growth of nestling songbirds

    USGS Publications Warehouse

    Mitchell, R.T.; Blagbrough, H.P.; VanEtten, R.C.

    1953-01-01

    In an experiment conducted during the summers of 1949 and 1950 at the Patuxent Research Refuge, Laurel, Maryland, two aerial applications of DDT were made at the rate of 3 pounds per acre. Sprayings were made over an experimental area of about 20 acres of abandoned fields bordered by woods and hedgerows. T\\vo hundred and ninetythree bird boxes, with three different sizes of openings to accommodate various species of hole-nesting birds, were distributed throughout this area and in a similar check area of the same size. House wrens were the most numerous and most productive of the species restricting their activities to the areas under study, and therefore they provided the most reliable information on survival and growth-rate after spraying. A total of 149 nestling wrens were under observation in 1949 and 154 in 1950. .....There were only slight decreases in the total adult bird populations, no increase in the number of cases of desertion, no significant differences in feeding ranges through the reduction of insect food, nor any apparent avoidance of the sprayed area by nesting birds. DDT at the 3 pounds-per-acre dosage caused considerable mortality to young nestlings. The fledging success in six active first-brood wren nests in 1949 was 28 percent compared to 86 percent in the unsprayed check. In 1950, when the area was sprayed at an earlier date in respect to both the calendar and the nesting progress of the first-brood wrens, fledging success in the sprayed area was 70 percent compared to 73 percent in the check. Average weights of first-brood wren nestlings in the sprayed area in both 1949 and 1950 were significantly lower than those in the check area. The weights of second-brood nestlings in 1949 were lover than those of the checks but the differences were not significant statistically. In 1950 the weights of second-brood house wrens in the sprayed area closely approximated those of the check.....Insect-sampling showed that shortly after spraying, the check

  11. Magnitude and origin of polychlorinated biphenyl (PCB) and dichlorodiphenyltrichloroethane (DDT) compounds resuspended in southern Lake Michigan

    NASA Astrophysics Data System (ADS)

    Hornbuckle, Keri C.; Smith, Gretchen L.; Miller, Sondra M.; Eadie, Brian J.; Lansing, Margaret B.

    2004-05-01

    Polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT) compounds are introduced into the water as a result of large-scale storms and sediment resuspension in the southern basin of Lake Michigan. Settling and suspended sediments, as well as air and water samples, were collected in southern Lake Michigan over a 12 month period. Analysis of contaminant fluxes on settling particles shows that approximately 370 kg of PCBs and 110 kg of DDT compounds are resuspended in southern Lake Michigan during a single basin-wide event (January 1999). Examination of contaminant signals indicates strong regional and temporal source-receptor relationships between settling, suspended, and surficial sediments. The settling, suspended, and bottom surficial sediments in the shallow waters of the southern coastal region are enriched in lower molecular weight PCBs. The sediments in the water column and on the lake bottom in the deeper regions are enriched in higher molecular weight PCBs. Furthermore, falling sediments collected in the deeper regions of the lake are enriched in 4,4'-DDT. The unique contaminant signal in deep water regions is surprising and suggests a source/receptor relationship among the bottom sediments and the sediments suspended and settling above them.

  12. Secondary metabolites from Ganoderma.

    PubMed

    Baby, Sabulal; Johnson, Anil John; Govindan, Balaji

    2015-06-01

    Ganoderma is a genus of medicinal mushrooms. This review deals with secondary metabolites isolated from Ganoderma and their biological significance. Phytochemical studies over the last 40years led to the isolation of 431 secondary metabolites from various Ganoderma species. The major secondary compounds isolated are (a) C30 lanostanes (ganoderic acids), (b) C30 lanostanes (aldehydes, alcohols, esters, glycosides, lactones, ketones), (c) C27 lanostanes (lucidenic acids), (d) C27 lanostanes (alcohols, lactones, esters), (e) C24, C25 lanostanes (f) C30 pentacyclic triterpenes, (g) meroterpenoids, (h) farnesyl hydroquinones (meroterpenoids), (i) C15 sesquiterpenoids, (j) steroids, (k) alkaloids, (l) prenyl hydroquinone (m) benzofurans, (n) benzopyran-4-one derivatives and (o) benzenoid derivatives. Ganoderma lucidum is the species extensively studied for its secondary metabolites and biological activities. Ganoderma applanatum, Ganoderma colossum, Ganoderma sinense, Ganoderma cochlear, Ganoderma tsugae, Ganoderma amboinense, Ganoderma orbiforme, Ganoderma resinaceum, Ganoderma hainanense, Ganoderma concinna, Ganoderma pfeifferi, Ganoderma neo-japonicum, Ganoderma tropicum, Ganoderma australe, Ganoderma carnosum, Ganoderma fornicatum, Ganoderma lipsiense (synonym G. applanatum), Ganoderma mastoporum, Ganoderma theaecolum, Ganoderma boninense, Ganoderma capense and Ganoderma annulare are the other Ganoderma species subjected to phytochemical studies. Further phytochemical studies on Ganoderma could lead to the discovery of hitherto unknown biologically active secondary metabolites. PMID:25975187

  13. Understanding and Classifying Metabolite Space and Metabolite-Likeness

    PubMed Central

    Peironcely, Julio E.; Reijmers, Theo; Coulier, Leon; Bender, Andreas; Hankemeier, Thomas

    2011-01-01

    While the entirety of ‘Chemical Space’ is huge (and assumed to contain between 1063 and 10200 ‘small molecules’), distinct subsets of this space can nonetheless be defined according to certain structural parameters. An example of such a subspace is the chemical space spanned by endogenous metabolites, defined as ‘naturally occurring’ products of an organisms' metabolism. In order to understand this part of chemical space in more detail, we analyzed the chemical space populated by human metabolites in two ways. Firstly, in order to understand metabolite space better, we performed Principal Component Analysis (PCA), hierarchical clustering and scaffold analysis of metabolites and non-metabolites in order to analyze which chemical features are characteristic for both classes of compounds. Here we found that heteroatom (both oxygen and nitrogen) content, as well as the presence of particular ring systems was able to distinguish both groups of compounds. Secondly, we established which molecular descriptors and classifiers are capable of distinguishing metabolites from non-metabolites, by assigning a ‘metabolite-likeness’ score. It was found that the combination of MDL Public Keys and Random Forest exhibited best overall classification performance with an AUC value of 99.13%, a specificity of 99.84% and a selectivity of 88.79%. This performance is slightly better than previous classifiers; and interestingly we found that drugs occupy two distinct areas of metabolite-likeness, the one being more ‘synthetic’ and the other being more ‘metabolite-like’. Also, on a truly prospective dataset of 457 compounds, 95.84% correct classification was achieved. Overall, we are confident that we contributed to the tasks of classifying metabolites, as well as to understanding metabolite chemical space better. This knowledge can now be used in the development of new drugs that need to resemble metabolites, and in our work particularly for assessing the metabolite

  14. Microalgal metabolites: a new perspective.

    PubMed

    Shimizu, Y

    1996-01-01

    Occurrence of secondary metabolites in microalgae (protoctista) is discussed with respect to the phylogenic or taxonomic relationships of organisms. Biosynthetic mechanisms of certain metabolites such as paralytic shellfish poisoning toxins and polyether toxins are also discussed, and genetic aspects of the secondary metabolite production as well. PMID:8905087

  15. Association between Lung Function in Adults and Plasma DDT and DDE Levels: Results from the Canadian Health Measures Survey

    PubMed Central

    Ye, Ming; Beach, Jeremy; Martin, Jonathan W.

    2014-01-01

    Background Although DDT [1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane] has been banned in many countries since the 1970s, it may still pose a risk to human respiratory health. In agriculture, DDT exposures have been associated with asthma and chronic bronchitis. However, little is known about the effect of DDT on lung function. Methods We used data on 1,696 participants 20–79 years of age from the Canadian Health Measures Survey (CHMS) and conducted multiple regression analysis to estimate associations between plasma p,p´-DDT/DDE and lung function. Results Almost all participants (> 99.0%) had detectable concentrations of plasma p,p´-DDE, but only 10.0% had detectable p,p´-DDT. Participants with detectable p,p´-DDT had significantly lower mean FVC (difference = 311 mL; 95% CI: –492, –130; p = 0.003) and FEV1 (difference = 232 mL; 95% CI: –408, –55; p = 0.015) than those without. A 100-ng/g lipid increase in plasma p,p´-DDE was associated with an 18.8-mL decrease in mean FVC (95% CI: –29, –9) and an 11.8-mL decrease in mean FEV1 (95% CI: –21, –3). Neither exposure was associated with FEV1/FVC ratio or FEF25%–75%. Conclusions DDT exposures, which may have occurred decades ago, were still detectable among Canadians. Plasma DDT and DDE were negatively associated with lung function parameters. Additional research on the potential effects of DDT use on lung function is warranted. Citation Ye M, Beach J, Martin JW, Senthilselvan A. 2015. Association between lung function in adults and plasma DDT and DDE levels: results from the Canadian Health Measures Survey. Environ Health Perspect 123:422–427; http://dx.doi.org/10.1289/ehp.1408217 PMID:25536373

  16. Metabolite Damage and Metabolite Damage Control in Plants.

    PubMed

    Hanson, Andrew D; Henry, Christopher S; Fiehn, Oliver; de Crécy-Lagard, Valérie

    2016-04-29

    It is increasingly clear that (a) many metabolites undergo spontaneous or enzyme-catalyzed side reactions in vivo, (b) the damaged metabolites formed by these reactions can be harmful, and (c) organisms have biochemical systems that limit the buildup of damaged metabolites. These damage-control systems either return a damaged molecule to its pristine state (metabolite repair) or convert harmful molecules to harmless ones (damage preemption). Because all organisms share a core set of metabolites that suffer the same chemical and enzymatic damage reactions, certain damage-control systems are widely conserved across the kingdoms of life. Relatively few damage reactions and damage-control systems are well known. Uncovering new damage reactions and identifying the corresponding damaged metabolites, damage-control genes, and enzymes demands a coordinated mix of chemistry, metabolomics, cheminformatics, biochemistry, and comparative genomics. This review illustrates the above points using examples from plants, which are at least as prone to metabolite damage as other organisms. PMID:26667673

  17. Polychlorinated biphenyls, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p{prime}-DDT) and 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p{prime}-DDE) in human plasma related to fish consumption

    SciTech Connect

    Asplund, L.; Eriksson, U.; Jansson, B.; Wideqvist, U.; Svensson, B.G.; Nilsson, A.; Skerfving, S.; Jensen, S.

    1994-11-01

    Fatty fish species, e.g., salmon and herring, in the Baltic Sea have high levels of polychlorinated biphenyls (PCBs) and 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p{prime}-DDT), and its main metabolite: 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p{prime}-DDE). We determined levels of 10 different PCB congeners, including non- and mono-ortho-PCBs, as well as DDT and DDE, in human blood plasma from 37 subjects with varying intake of fish (0-1 750 g/wk) from the Baltic Sea. With respect to all of the PCB congeners we investigated, as well as for DDT and DDE, there were statistically significant associations with fish intake. Thus, fish from the Baltic Sea is a major source of exposure to these compounds in Swedes. Polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) had been determined earlier in 29 of the subjects. The PCB contribution to {open_quotes}dioxin-like{close_quotes} effects among high consumers of fish (calculated as Nordic TCDD equivalents) was almost 80%, whereas that from PCDD and PCDF was only 20%. 32 refs., 3 figs., 9 tabs.

  18. The influence of non-toxic concentrations of DDT and DDE on the old world vulture estrogen receptor alpha.

    PubMed

    Naidoo, Vinny; Katsu, Yoshinao; Iguchi, Taisen

    2008-01-01

    Seven of the nine vulture species in South Africa are listed as endangered on the International Union for the Conservation of Nature (IUCN) red list. From these, the Cape Griffon vulture (Gyps corprotheres) is the most endangered species in the region. Although inadequate nutritional support has been blamed on the constant decline in populations, the process of vulture restaurants has failed to improve the population status over the last twenty years. One possible reason for the decline may be an underlying reproductive disorder as described in endocrine disruptive syndromes. Both DDT and p,p'-DDE have been detected previously at very high concentrations in the mid 1980s, with lower concentrations still being detectable as late as 2001. To establish the effect of DDT and DDE, the vulture estrogen receptor alpha (ERalpha) was sequenced from two species using 5' and 3' rapid amplification cDNA ends (RACE). Using transient transfected mammalian cell assays, vulture ERalpha estrogen-dependent transcription activity was validated using various estrogens and DDT derivatives. The receptor assay was sensitive to p,p'-DDT, o,p'-DDT and p,p'-DDE with EC(50) of 2.41x10(-6), 3.47x10(-7) and 3.81x10(-5)M. When compared to results obtained from human, zebrafish, chicken, salamander and turtle, the vulture ERalpha showed high sensitivity to o,p'-DDT and intermediately responsive to p,p'-DDE. Vulture ERalpha is, however, not responsive to the DDT and DDE levels reported in the plasma of vultures from the last population survey, indicating that the Southern African vulture are not currently exposed to disruptive levels of these contaminants. PMID:18801367

  19. Assessing the underlying breast cancer risk of Chinese females contributed by dietary intake of residual DDT from agricultural soils.

    PubMed

    Tang, Mengling; Zhao, Meirong; Zhou, Shanshan; Chen, Kun; Zhang, Chunlong; Liu, Weiping

    2014-12-01

    The greatest concern over DDT exposure in China arose since the early 1990s for the rising breast cancer incidence, and the cause still remains to be elucidated. An extensive survey of DDT background in agricultural soils, covered the entire region of China, was conducted. DDT at concentrations greater than 100 ng/g (the China's Farmland Environmental Quality Evaluation Standards for Edible Agricultural Products) was found to impact 42.3 million Chinese population. Considering the geographical differences with diverse DDT contributions and different diet products and habits, the average daily dietary intake was modeled and estimated to be 0.34 μg/kg p,p'-DDE (the main bioactive constituent in DDT). Population attributable fraction derived from a case-control study from 78 women with breast cancer and 72 controls was used to assess the DDT exposure risk to breast cancer. Based on the estimated population attributable fraction with a median value of 0.6% (IQR 0.23-2.11%), the excess annual breast cancer incidence rate attributable to p,p'-DDE exposure averaged 0.06×10(-5) with significant spatial variations varying from 0.00021×10(-5) to 11.05×10(-5) in Chinese females. Exposure to DDT is a contributor to breast cancer, but the overall limited relative risk and population attributable fraction imply confounding factors for breast cancer in Chinese females. Exposure risk in a regional scale helps understand the cause and prevention of breast cancer. Our mapping and modeling method could be used to assess other environmental carcinogens and related cancer diseases. PMID:25160079

  20. An experimental hut study to quantify the effect of DDT and airborne pyrethroids on entomological parameters of malaria transmission

    PubMed Central

    2014-01-01

    Background Current malaria vector control programmes rely on insecticides with rapid contact toxicity. However, spatial repellents can also be applied to reduce man-vector contact, which might ultimately impact malaria transmission. The aim of this study was to quantify effects of airborne pyrethroids from coils and DDT used an indoor residual spray (IRS) on entomological parameters that influence malaria transmission. Methods The effect of Transfluthrin and Metofluthrin coils compared to DDT on house entry, exit and indoor feeding behaviour of Anopheles gambiae sensu lato were measured in experimental huts in the field and in the semi-field. Outcomes were deterrence - reduction in house entry of mosquitoes; irritancy or excito-repellency – induced premature exit of mosquitoes; blood feeding inhibition and effect on mosquito fecundity. Results Transfluthrin coils, Metofluthrin coils and DDT reduced human vector contact through deterrence by 38%, 30% and 8%, respectively and induced half of the mosquitoes to leave huts before feeding (56%, 55% and 48%, respectively). Almost all mosquitoes inside huts with Metofluthrin and Transfluthrin coils and more than three quarters of mosquitoes in the DDT hut did not feed, almost none laid eggs and 67%, 72% and 70% of all mosquitoes collected from Transfluthrin, Metofluthrin and DDT huts, respectively had died after 24 hours. Conclusion This study highlights that airborne pyrethroids and DDT affect a range of anopheline mosquito behaviours that are important parameters in malaria transmission, namely deterrence, irritancy/excito-repellency and blood-feeding inhibition. These effects are in addition to significant toxicity and reduced mosquito fecundity that affect mosquito densities and, therefore, provide community protection against diseases for both users and non-users. Airborne insecticides and freshly applied DDT had similar effects on deterrence, irritancy and feeding inhibition. Therefore, it is suggested that

  1. Evidence for Dual Binding Sites for 1,1,1-Trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) in Insect Sodium Channels.

    PubMed

    Du, Yuzhe; Nomura, Yoshiko; Zhorov, Boris S; Dong, Ke

    2016-02-26

    1,1,1-Trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), the first organochlorine insecticide, and pyrethroid insecticides are sodium channel agonists. Although the use of DDT is banned in most of the world due to its detrimental impact on the ecosystem, indoor residual spraying of DDT is still recommended for malaria control in Africa. Development of resistance to DDT and pyrethroids is a serious global obstacle for managing disease vectors. Mapping DDT binding sites is necessary for understanding mechanisms of resistance and modulation of sodium channels by structurally different ligands. The pioneering model of the housefly sodium channel visualized the first receptor for pyrethroids, PyR1, in the II/III domain interface and suggested that DDT binds within PyR1. Previously, we proposed the second pyrethroid receptor, PyR2, at the I/II domain interface. However, whether DDT binds to both pyrethroid receptor sites remains unknown. Here, using computational docking of DDT into the Kv1.2-based mosquito sodium channel model, we predict that two DDT molecules can bind simultaneously within PyR1 and PyR2. The bulky trichloromethyl group of each DDT molecule fits snugly between four helices in the bent domain interface, whereas two p-chlorophenyl rings extend into two wings of the interface. Model-driven mutagenesis and electrophysiological analysis confirmed these propositions and revealed 10 previously unknown DDT-sensing residues within PyR1 and PyR2. Our study proposes a dual DDT-receptor model and provides a structural background for rational development of new insecticides. PMID:26637352

  2. Accumulation, distribution and transformation of DDT and PCBs by Phragmites australis and Oryza sativa L.: II. Enzyme study.

    PubMed

    Chu, W K; Wong, M H; Zhang, J

    2006-01-01

    Two wetland plant species, Phragmites australis and Oryza sativa, were grown in a glasshouse under hydroponics conditions. Enzyme extracts from different parts of the plants were used to determine the transformation rate of o,p'-DDT, p,p'-DDT and PCBs. The organic pollutants were directly spiked into the enzyme extracts, and samples were collected every 30 min and analyzed with a GC-ECD. Root extracts of P. australis readily degraded and transformed DDT and some PCB congeners with a low degree of chlorination. In contrast, crude extracts of O. sativa showed no appreciable degradation or transformation of DDT or PCBs. Inhibition studies indicated that the degradation and transformation of both DDT and PCBs by P. australis enzymes were partly mediated by peroxidase and the plant P-450 system. PCBs with a high degree of chlorination were highly resistant to transformation or degradation by plant enzymes. Both wetland plant species accumulated substantial quantities of the persistent organic chemicals but had different degradation capacities. The enzyme systems in P. australis were much more effective that those in rice in the degradation and transformation of the organic pollutants. PMID:16547764

  3. Residues of polychlorinated biphenyls and DDT in water and sediment of the Indian River Lagoon, Florida - 1977 to 1978

    SciTech Connect

    Wang, T.C.; Johnson, R.S.; Bricker, J.L.

    1980-01-01

    Water and sediment samples collected during 1977 to 1978 from the Indian River lagoon between Vero Beach, Indian River County, and Fort Pierce, Saint Lucie County, Florida were analyzed for PCBs and DDT. Sample locations were chosen on the basis of proximity to major tributaries, sewage outfalls, or municipal area. Concentrations in water samples were below 0.01 ppB sigma DDT and 0.5 ppB PCBs. Small amounts of PCBs and DDT were found in most sediment samples, ranging from less than 1.0 ppB to 0.63 ppM Aroclor 1254 and from less than 0.1 ppB to 0.081 ppM sigma DDT. Samples from the Taylor Creek tributary and from the Fort Pierce power plant and municipal docking area contained higher PCB concentrations than did samples from other locations. DDT and PCB levels in most samples indicate little contamination by these compounds of the Indian River Waterway between Vero Beach and Fort Pierce.

  4. Design and optimization of a deflagration to detonation transition (ddt) section

    NASA Astrophysics Data System (ADS)

    Romo, Francisco X.

    Throughout the previous century, hydrocarbon-fueled engines have used and optimized the `traditional' combustion process called deflagration (subsonic combustion). An alternative form of combustion, detonation (supersonic combustion), can increase the thermal efficiency of the process by anywhere from 20 - 50%. Even though several authors have studied detonation waves since the 1890's and a plethora of papers and books have been published, it was not until 2008 that the first detonation-powered flight took place. It lasted for 10 seconds at 100 ft. altitude. Achieving detonation presents its own challenges: some fuels are not prone to detonate, severe vibrations caused by the cyclic nature of the engine and its intense noise are some of the key areas that need further research. Also, to directly achieve detonation either a high-energy, bulky, ignition system is required, or the combustion chamber must be fairly long (5 ft. or more in some cases). In the latter method, a subsonic flame front accelerates within the combustion chamber until it reaches supersonic speeds, thus detonation is attained. This is called deflagration-todetonation transition (DDT). Previous papers and experiments have shown that obstacles, such as discs with an orifice, located inside the combustion chamber can shorten the distance required to achieve detonation. This paper describes a hands-on implementation of a DDT device. Different disc geometries inside the chamber alter the wave characteristics at the exit of the tube. Although detonation was reached only when using pure oxygen, testing identified an obstacle configuration for LPG and air mixtures that increased pressure and wave speed significantly when compared to baseline or other obstacle configurations. Mixtures of LPG and air were accelerated to Mach 0.96 in the downstream frame of reference, which would indicate a transition to detonation was close. Reasons for not achieving detonation may include poor fuel and oxidizer mixing

  5. Ban of DDT and subsequent recovery of Reproduction in bald eagles

    SciTech Connect

    Grier, J.W.

    1982-12-17

    Reproduction of bald eagles in northwestern Ontario declined from 1.26 young per breeding area in 1966 to a low of 0.46 in 1974 and then increased to 1.12 in 1981. Residues of DDE in addled eggs showed a significant inverse relation, confirming the effects of this toxicant on bald eagle reproduction at the population level and the effectiveness of the ban on DDT. The recovery from DDE contamination in bald eagles appears to be occurring much more rapidly than predicted.

  6. Linkage studies on DDT and dieldrin resistance in species A and species B of the Anopheles gambiae complex

    PubMed Central

    Haridi, A. M.

    1974-01-01

    Linkage studies in A. gambiae species A showed that the two autosomal markers diamond (Di) and collarless (c) belonged to different linkage groups: Di on linkage group 2 and c on linkage group 3. With the aid of the two markers it was possible to establish the linkage relationship between the genes for DDT resistance and for the two types of dieldrin resistance. The DDT resistance gene in species A assorted independently of c and was found to be linked with Di at a map distance of 26.3 units. The genes for the two types of dieldrin resistance, dominant and incompletely dominant, were found to be allelic. The major gene for dieldrin resistance was shown to be linked with the gene for DDT resistance in linkage group 2 at a map distance of 35.3 units. This suggested that Di and the dieldrin resistance gene were some 61.6 units apart. PMID:4616778

  7. [Antiviral properties of basidiomycetes metabolites].

    PubMed

    Avtonomova, A V; Krasnopolskaya, L M

    2014-01-01

    The data on the antiviral action of the Ganoderma lucidum, Lentinus edodes, Grifola frondosa, Agaricus brasiliensis and other basidiomycetes metabolites are summurized. The metabolites of these species of basidiomycetes exhibit a direct antiviral effect on herpes simplex virus types I and II, human immunodeficiency virus (HIV), hepatitis B virus, vesicular stomatitis virus, influenza virus, Epstein-Barr virus, and others. Moreover, metabolites of basidiomycetes increased antiviral immunity. PMID:25975107

  8. Physiological effects of polychlorinated biphenyls or a combination of DDT, DDD, and DDE in penned white pelicans.

    PubMed

    Greichus, Y A; Call, D J; Ammann, B M

    1975-01-01

    The effects of PCBs (polychlorinated biphenyls) or a combination of DDT (1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane), DDD (1,1-dichloro-2,2-bis (p-chlorophenyl) ethane) and DDE (1,1-dichloro-2,2,-bis (p-chlorophenyl ethylene) on organ weights, liver storage of vitamin A and carotene, selected blood chemistry parameters, and serum protein fractions were determined in penned white pelicans (Pelecanus erythrorhynchos) receiving a daily dosage of these compounds. Birds received 100 mg of PCBs or a combination of DDT (20 mg), DDD (15 mg), and DDE (15 mg) injected into the first fish fed each day for ten weeks. A greater percentage of PCB treatment was retained in brain, liver, carcass and feathers than the percentage of DDT + DDD + DDE treatment. Liver weight as percent of body weight decreased (p less than 0.01) in DDT + DDD + DDE-treated birds and increased (p less than 0.01) as a total weight in PCB-treated birds. Spleen weight as percent of body weight was greater (p less than 0.05) in PCB-treated birds. Neither treatment had a significant effect on the weight of the brain, heart, or kidney. Liver vitamin A levels were greater (p less than 0.01) on a mug/g of liver basis in the DDT-treated birds than in controls. Significant lowering of serum potassium and protein values was noted in both the PCB- and the combination of DDT, DDD, DDE-treated birds, while serum calcium values were lowered (p less than 0.01) only in PCB-treated birds. Vaues of serum inorganic phosphorus, uric acid and magnesium were not significantly changed by either treatment. Globulin fractions were unaltered by either treatment, but albumin fractions were lowered (p less than 0.01) in the PCB-treated pelicans. PMID:811179

  9. Permethrin-impregnated bednets are more effective than DDT house-spraying to control malaria in Solomon Islands.

    PubMed

    Kere, N K; Arabola, A; Bakote'e, B; Qalo, O; Burkot, T R; Webber, R H; Southgate, B A

    1996-04-01

    A field trial compared DDT house-spraying with permethrin-impregnated bednets for malaria control in Solomon Islands from 1987 to 1991. Mortality-rates of malaria vector Anopheles farauti in exit window traps were 11.6% from an untreated hut, 10.1% from a hut sprayed with DDT 2 g/m2, and 98% of those from a hut in which the occupants used bednets treated with permethrin 0.5 g/m2. Since bioassays of the DDT-sprayed walls (15 min exposure in W.H.O. standard test cones) gave 77% mortality of An.farauti, it was concluded that the insignificant impact of DDT could be explained by the exophilic behaviour of endophagic vectors, whereas the greater impact of permethrin was attributed to the more effective exposure of An.farauti females to the impregnated bednets-attracted by the occupants. The parous rate was higher indoors, except in the area with permethrin-impregnated bednets. It was therefore concluded that permethrin-impregnated bednets reduced the mean longevity of An.farauti and hence its vectorial capacity. The circumsporozoite (CS) antigen positivity rate of An.farauti in the DDT area was 0.18% outdoors, significantly less than 1.42% indoors. In the comparison area CS rates were 0.65% outdoors and 0.75% indoors. CS antigen was not detected in An.farauti from the bednet area, indicating the apparent prevention of malaria transmission. As DDT spraying was so much less effective, it was discontinued in 1993 and permethrin-impregnated bednets are now the principal malaria control method in Solomon Islands. PMID:8744706

  10. Percutaneous absorption of ( sup 14 C)DDT and ( sup 14 C)benzo(a)pyrene from soil

    SciTech Connect

    Wester, R.C.; Maibach, H.I.; Bucks, D.A.; Sedik, L.; Melendres, J.; Liao, C.; DiZio, S. )

    1990-10-01

    The objective was to determine percutaneous absorption of DDT and benzo(a)pyrene in vitro and in vivo from soil into and through skin. Soil (Yolo County 65-California-57-8; 26% sand, 26% clay, 48% silt) was passed through 10-, 20-, and 48-mesh sieves. Soil then retained by 80-mesh was mixed with (14C)-labeled chemical at 10 ppm. Acetone solutions at 10 ppm were prepared for comparative analysis. Human cadaver skin was dermatomed to 500 microns and used in glass diffusion cells with human plasma as the receptor fluid (3 ml/hr flow rate) for a 24-hr skin application time. With acetone vehicle, DDT (18.1 +/- 13.4%) readily penetrated into human skin. Significantly less DDT (1.0 +/- 0.7%) penetrated into human skin from soil. DDT would not partition from human skin into human plasma in the receptor phase (less than 0.1%). With acetone vehicle, benzo(a)pyrene (23.7 +/- 9.7%) readily penetrated into human skin. Significantly less benzo(a)pyrene (1.4 +/- 0.9%) penetrated into human skin from soil. Benzo(a)pyrene would not partition from human skin into human plasma in the receptor phase (less than 0.1%). Substantivity (skin retention) was investigated by applying 14C-labeled chemical to human skin in vitro for only 25 min. After soap and water wash, 16.7 +/- 13.2% of DDT applied in acetone remained absorbed to skin. With soil only 0.25 +/- 0.11% of DDT remained absorbed to skin. After soap and water wash 5.1 +/- 2.1% of benzo(a)pyrene applied in acetone remained absorbed to skin. With soil only 0.14 +/- 0.13% of benzo(a)pyrene remained absorbed to skin.

  11. Distinct roles of the DmNav and DSC1 channels in the action of DDT and pyrethroids.

    PubMed

    Rinkevich, Frank D; Du, Yuzhe; Tolinski, Josh; Ueda, Atsushi; Wu, Chun-Fang; Zhorov, Boris S; Dong, Ke

    2015-03-01

    Voltage-gated sodium channels (Nav channels) are critical for electrical signaling in the nervous system and are the primary targets of the insecticides DDT and pyrethroids. In Drosophila melanogaster, besides the canonical Nav channel, Para (also called DmNav), there is a sodium channel-like cation channel called DSC1 (Drosophila sodium channel 1). Temperature-sensitive paralytic mutations in DmNav (para(ts)) confer resistance to DDT and pyrethroids, whereas DSC1 knockout flies exhibit enhanced sensitivity to pyrethroids. To further define the roles and interaction of DmNav and DSC1 channels in DDT and pyrethroid neurotoxicology, we generated a DmNav/DSC1 double mutant line by introducing a para(ts1) allele (carrying the I265N mutation) into a DSC1 knockout line. We confirmed that the I265N mutation reduced the sensitivity to two pyrethroids, permethrin and deltamethrin of a DmNav variant expressed in Xenopus oocytes. Computer modeling predicts that the I265N mutation confers pyrethroid resistance by allosterically altering the second pyrethroid receptor site on the DmNav channel. Furthermore, we found that I265N-mediated pyrethroid resistance in para(ts1) mutant flies was almost completely abolished in para(ts1);DSC1(-/-) double mutant flies. Unexpectedly, however, the DSC1 knockout flies were less sensitive to DDT, compared to the control flies (w(1118A)), and the para(ts1);DSC1(-/-) double mutant flies were even more resistant to DDT compared to the DSC1 knockout or para(ts1) mutant. Our findings revealed distinct roles of the DmNav and DSC1 channels in the neurotoxicology of DDT vs. pyrethroids and implicate the exciting possibility of using DSC1 channel blockers or modifiers in the management of pyrethroid resistance. PMID:25687544

  12. The development of laser ignited deflagration-to-detonation transition (DDT) detonators and pyrotechnic actuators

    SciTech Connect

    Merson, J.A.; Salas, F.J.; Harlan, J.G.

    1993-11-01

    The use of laser ignited explosive components has been recognized as a safety enhancement over existing electrical explosive devices (EEDs). Sandia has been pursuing the development of optical ordnance for many years with recent emphasis on developing optical deflagration-to-detonation (DDT) detonators and pyrotechnic actuators. These low energy optical ordnance devices can be ignited with either a semiconductor diode laser, laser diode arrays or a solid state rod laser. By using a semiconductor laser diode, the safety improvement can be made without sacrificing performance since the input energy required for the laser diode and the explosive output are similar to existing electrical systems. The use of higher powered laser diode arrays or rod lasers may have advantages in fast DDT applications or lossy optical environments such as long fiber applications and applications with numerous optical connectors. Recent results from our continued study of optical ignition of explosive and pyrotechnic materials are presented. These areas of investigation can be separated into three different margin categories: (1) the margin relative to intended inputs (i.e. powder performance as a function of laser input variation), (2) the margin relative to anticipated environments (i.e. powder performance as a function of thermal environment variation), and (3) the margin relative to unintended environments (i.e. responses to abnormal environments or safety).

  13. Promoting and anticarcinogenic effects of phenobarbital and DDT in the rat hepatocarcinogenesis.

    PubMed

    Kitagawa, T

    1986-01-01

    The possible discrepancy between the dose level required for promoting action (when given after the initiation process, and that needed to exert an anticarcinogenic effect when given simultaneously with a carcinogen) of hepatic promoters were investigated in an attempt to obtain a "practical" threshold dose of promoters. Phenobarbital (PB) and dichlorophenyltrichlorethane (DDT) were used as promoters and 3'-methyl-4-(dimethylamino)-azobenzene (3'-Me-DAB) was used as the carcinogen. Male weanling rats were treated with either 600 ppm 3'-Me-DAB for 3 weeks followed by a diet containing a promoter at various dose levels (5-500 ppm), or the animals were treated with a low dose (100 ppm) of 3'-Me-DAB plus a promoter at various dose levels (20-500 ppm). The effects of promoters were measured by scoring size and number of enzyme-altered islands (EAIs) at 12 and 24 weeks of age. The promoting effect of PB and DDT was demonstrated in dose-dependent fashion, in the dose range of 10-500 ppm and 20-500 ppm, respectively. On the other hand, promoters given simultaneously with a low dose of carcinogen enhanced carcinogenesis at all the dose levels tested, in contrast with the inhibitory effect on carcinogenesis when given together with relatively high doses of carcinogens. PMID:3787112

  14. Experimental Study on DDT Characteristics in Spiral Configuration Pulse Detonation Engines

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Qiu, Hua; Fan, Wei; Xiong, Cha

    2013-09-01

    This work investigated features of the deflagration to detonation transition in a curved tube. A number of experiments were performed to acquire the transition rule of DDT, which would provide the design data and theoretical basis for the curved detonation chamber. The content of research is as follows: (1) Flow resistance experiments of nine detonation chambers have been explored. The results show that the spiral configuration can reduce the axial length of DC, and the total pressure recovery coefficient increases with the spiral pitch. (2) Single-cycle detonation experiments have been conducted using the 9 tubes in the resistance experiments. Liquid-gasoline/air is used as the detonative mixture in all the experiments. The detonation experimental results indicate that there is no detonation wave formed in the straight tube, but in all the selected spiral tubes fully-developed detonation waves have been obtained; compared to the straight tube case, the DDT time decrease with the decreasing of the radius of curvature (RC) by 6.2%˜19.8% in the spiral detonation tubes.

  15. Development and qualification testing of a laser-ignited, all-secondary (DDT) detonator

    NASA Technical Reports Server (NTRS)

    Blachowski, Thomas J.; Krivitsky, Darrin Z.; Tipton, Stephen

    1994-01-01

    The Indian Head Division, Naval Surface Warfare Center (IHDIV, NSWC) is conducting a qualification program for a laser-ignited, all-secondary (DDT) explosive detonator. This detonator was developed jointly by IHDIV, NSWC and the Department of Energy's EG&G Mound Applied Technologies facility in Miamisburg, Ohio to accept a laser initiation signal and produce a fully developed shock wave output. The detonator performance requirements were established by the on-going IHDIV, NSWC Laser Initiated Transfer Energy Subsystem (LITES) advanced development program. Qualification of the detonator as a component utilizing existing military specifications is the selected approach for this program. The detonator is a deflagration-to-detonator transfer (DDT) device using a secondary explosive, HMX, to generate the required shock wave output. The prototype development and initial system integration tests for the LITES and for the detonator were reported at the 1992 International Pyrotechnics Society Symposium and at the 1992 Survival and Flight Equipment National Symposium. Recent results are presented for the all-fire sensitivity and qualification tests conducted at two different laser initiation pulses.

  16. Estrogenic Activity of Coumestrol, DDT, and TCDD in Human Cervical Cancer Cells

    PubMed Central

    Ndebele, Kenneth; Graham, Barbara; Tchounwou, Paul B.

    2010-01-01

    Endogenous estrogens have dramatic and differential effects on classical endocrine organ and proliferation. Xenoestrogens are environmental estrogens that have endocrine impact, acting as both estrogen agonists and antagonists, but whose effects are not well characterized. In this investigation we sought to delineate effects of xenoestrogens. Using human cervical cancer cells (HeLa cells) as a model, the effects of representative xenoestrogens (Coumestrol-a phytoestrogen, tetrachlorodioxin (TCDD)-a herbicide and DDT-a pesticide) on proliferation, cell cycle, and apoptosis were examined. These xenoestrogens and estrogen inhibited the proliferation of Hela cells in a dose dependent manner from 20 to 120 nM suggesting, that 17-β-estrtadiol and xenoestrogens induced cytotoxic effects. Coumestrol produced accumulation of HeLa cells in G2/M phase, and subsequently induced apoptosis. Similar effects were observed in estrogen treated cells. These changes were associated with suppressed bcl-2 protein and augmented Cyclins A and D proteins. DDT and TCDD exposure did not induce apoptosis. These preliminary data taken together, suggest that xenoestrogens have direct, compound-specific effects on HeLa cells. This study further enhances our understanding of environmental modulation of cervical cancer. PMID:20623010

  17. Effects of DDT on the calcium transport and thymidine uptake of bovine lymphocytes

    SciTech Connect

    McCabe, M.; Yin-Foo, D.

    1986-10-01

    It is known that organochlorine compounds in the environment present risks which may be related to an interference with calcium metabolism. The evidence in favor of a role for intracellular calcium levels as signals for the initiation of cell division is summarized by Metcalfe et al., and forms the basis for a calcium hypothesis for the control of cell growth. Lymphocytes undergoing transformation provide evidence for an involvement of calcium in the steps preceding mitogenic activation which occur within 20 hours of exposure to a mitogen. It has been suspected for some time that the incidence of lymphomas and leukemias may be higher in farming populations with significant past exposure to several organochlorine insecticides. It is also known that immune suppression can provoke an increase in the incidence of certain cancers, although whether this is an example of (lack of) immune surveillance for potential cancer cells or of some less direct mechanism such as a reduced resistance to a viral infection, is still unclear. For these reasons it is important to know whether DDT and other chemically related organochlorine compounds modulate calcium levels within lymphocytes, and if so whether this modulation relates to the observed effects of these compounds on lymphocyte mitogenesis. Such studies may also be of some value in providing a clue as to the relationship between chemically induced leukemias and DDT exposure.

  18. The development of laser ignited deflagration-to-detonation transition (DDT) detonators and pyrotechnic actuators

    SciTech Connect

    Merson, J.A.; Salas, F.J.

    1994-05-01

    The use of laser ignited explosive components has been recognized as a safety enhancement over existing electrical explosive devices (EEDs). Sandia has been pursuing the development of optical ordnance for many years with recent emphasis on developing optical deflagration-to-detonation (DDT) detonators and pyrotechnic actuators. These low energy optical ordnance devices can be ignited with either a semiconductor diode laser, laser diode arrays or a solid state rod laser. By using a semiconductor laser diode, the safety improvement can be made without sacrificing performance since the input energy required for the laser diode and the explosive output are similar to existing electrical systems. The use of higher powered laser diode arrays or rod lasers may have advantages in fast DDT applications or lossy optical environments such as long fiber applications and applications with numerous optical connectors. Recent results from our continued study of optical ignition of explosive and pyrotechnic materials are presented. These areas of investigation can be separated into three different margin categories: (1) the margin relative to intended inputs ( i.e. powder performance as a function of laser input variation), (2) the margin relative to anticipated environments (i.e. powder performance as a function of thermal environment variation), and (3) the margin relative to unintended environments (i.e. responses to abnormal environments or safety).

  19. Utilizing thin-film solid-phase extraction to assess the effect of organic carbon amendments on the bioavailability of DDT and dieldrin to earthworms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While DDT and dieldrin have been banned in most countries, contaminated agricultural sites exist in many areas and wildlife exposure is still of concern. Soil was obtained from a historical orchard that received routine pesticide applications more than 40 years ago. Bioavailability of DDT and diel...

  20. BIODEGRADATION OF DDT [1,1,1-TRICHLORO-2,2-BIS(4- CHLOROPHENYL) ETHANE] BY THE WHITE ROT FUNGUS PHANEROCHAETE CHRYSOSPORIUM

    EPA Science Inventory

    Extensive biodegradation of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) by the white rot fungus Phanerochaete chrysosporium was demonstrated by disappearance and mineralization of [14C]DDT in nutrient nitrogen-deficient cultures. Mass balance studies demonstrated the form...

  1. BIODEGRADATION OF DDT [1,1,1-TRICHLORO-2,2-BIS)4-CHLOROPHENYL) ETHANE] BY THE WHITE ROT FUNGUS PHANEROCHAETE CHRYSOSPORIUM

    EPA Science Inventory

    Extensive biodegradation of 1,1,1-trichloro-2,2bis(4-chlorophenyl) ethane (DDT) by the white rot fungus Phanerochaete chrysosporium was demonstrated by disappearance and mineralization of [14C]DDT in nutrient nitrogen-deficient cultures. ass balance studies demonstrated the forma...

  2. Evaluation of foam surfactant for foam-flushing technique in remediation of DDT-contaminated soil using data envelopment analysis method.

    PubMed

    Wang, Xingwei; Chen, Jiajun; Lv, Ce

    2015-02-01

    With an aim to select the most appropriate foaming surfactant for remediation of DDT-contaminated soil by foam-flushing technique, the performances of nonionic and anionic surfactant in several aspects were observed in this study. SDS had the best foam static characteristic among the four experimental surfactants. The solubilizing ability for DDT followed the order of Tween80 > TX100 > SDS > Brij35. The adsorption loss of SDS onto soil was the lowest. The order of desorption efficiency for DDT followed as TX-100 > Tween80 > Brij35 > SDS. Based on these experimental investigations, the overall performances of foaming surfactants were evaluated by data envelopment analysis method. The results indicated that SDS was the optimal alternative for remediation of DDT-contaminated soil by foam-flushing technique. This conclusion was reached with the consideration of the cost, foam static characteristic, surfactant adsorption loss, solubilizing ability, and desorption efficiency of surfactant for DDT. PMID:25226831

  3. Sun, shade, and secondary metabolites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    My research program focuses on understanding plant primary and secondary metabolites. Grape secondary metabolites, such as phenolics, have long been valuable for the organoleptic properties they impart to fruit and wine, and, more recently, for their possible health benefits. These compounds develop...

  4. Modeling the fate of p,p'-DDT in water and sediment of two typical estuarine bays in South China: Importance of fishing vessels' inputs.

    PubMed

    Fang, Shu-Ming; Zhang, Xianming; Bao, Lian-Jun; Zeng, Eddy Y

    2016-05-01

    Antifouling paint applied to fishing vessels is the primary source of dichloro-diphenyl-trichloroethane (DDT) to the coastal marine environments of China. With the aim to provide science-based support of potential regulations on DDT use in antifouling paint, we utilized a fugacity-based model to evaluate the fate and impact of p,p'-DDT, the dominant component of DDT mixture, in Daya Bay and Hailing Bay, two typical estuarine bays in South China. The emissions of p,p'-DDT from fishing vessels to the aquatic environments of Hailing Bay and Daya Bay were estimated as 9.3 and 7.7 kg yr(-1), respectively. Uncertainty analysis indicated that the temporal variability of p,p'-DDT was well described by the model if fishing vessels were considered as the only direct source, i.e., fishing vessels should be the dominant source of p,p'-DDT in coastal bay areas of China. Estimated hazard quotients indicated that sediment in Hailing Bay posed high risk to the aquatic system, and it would take at least 21 years to reduce the hazards to a safe level. Moreover, p,p'-DDT tends to migrate from water to sediment in the entire Hailing Bay and Daya Bay. On the other hand, our previous research indicated that p,p'-DDT was more likely to migrate from sediment to water in the maricultured zones located in shallow waters of these two bays, where fishing vessels frequently remain. These findings suggest that relocating mariculture zones to deeper waters would reduce the likelihood of farmed fish contamination by p,p'-DDT. PMID:27016888

  5. Passive air sampling of DDT, chlordane and HCB in the Pearl River Delta, South China: implications to regional sources.

    PubMed

    Wang, Jun; Guo, Lingli; Li, Jun; Zhang, Gan; Lee, Celine S L; Li, Xiangdong; Jones, Kevin C; Xiang, Yunrong; Zhong, Liuju

    2007-06-01

    The Pearl River Delta (PRD) is one of the largest fast-developing economic zones in China. Hong Kong and the mainland part of the PRD differed in socio-economic development history and chemical management policies. Polyurethane foam (PUF)-passive air sampling (PAS) was deployed at 21 regional air quality monitoring stations across the PRD in summer and winter, respectively. Dichloro-diphenyl-trichloroethane (DDT), chlordane and hexachlorobenzene (HCB) were analyzed with GC-MS. High total DDT (240-3700 pg m(-3)) and chlordane (100-2600 pg m(-3)) concentrations were observed. Concentrations of DDTs and chlordane were higher in summer than winter; HCB vice versa. Spatially, the mainland part of the PRD generally displayed higher DDT concentrations than Hong Kong. Antifouling paint for fishing ships in coastal China was suggested to be an important current DDT source in the coast. The reason is unknown for the very low trans-/cis-chlordane (TC/CC) ratios (0.27) found in the mainland in winter. HCB concentrations were relatively uniform across the PRD, and long range transport of HCB from inland/North China to the PRD in winter was suggested. PMID:17554430

  6. Effect of temperature on accumulation of methylmercuric chloride and p,p'DDT by rainbow trout (Salmo gairdneri)

    USGS Publications Warehouse

    Reinert, Robert E.; Stone, Linda J.; Willford, Wayne A.

    1974-01-01

    Amounts of mercury and DDT residues accumulated from water by yearling rainbow trout (Salmo gairdneri) in the laboratory increased as water temperature increased. Fish exposed to methylmercuric chloride at concentrations of 234–263 parts per trillion for 12 wk at 5, 10, and 15 C accumulated 1.19, 1.71, and 1.96 ppm; fish exposed to p,p′DDT at concentrations of 133–176 parts per trillion accumulated 3.76, 5.93, and 6.82 ppm. Concentrations of mercury accumulated by the fish were significantly different (P < 0.01) at each of the three temperatures, and the concentrations of DDT were significantly different at 5 and 10 and 5 and 15 C. Throughout the period of exposure, the concentration factors (concentration of contaminant in the fish/concentration in water) at each of the three temperatures were far higher for p,p′DDT than for methylmercuric chloride.

  7. DDT, PCB AND BENZO(A)PYRENE LEVELS IN WHITE CROAKER 'GENYONEMUS LINEATUS' FROM SOUTHERN CALIFORNIA (JOURNAL VERSION)

    EPA Science Inventory

    This paper presents the results of PCB, DDT and benzo(a)pyrene (BaP) determination in white croaker (Genyonemus lineatus) sampled from the coastal waters of metropolitan Los Angeles. The purpose of this research was to assess the potential health hazard caused by the consumption ...

  8. Water solubility enhancements of DDT and trichlorobenzene by some surfactants below and above the critical micelle concentration

    USGS Publications Warehouse

    Kile, D.E.; Chiou, C.T.

    1989-01-01

    Water solubility enhancements of 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (DDT) and 1,2,3-trichlorobenzene (TCB) by aqueous surfactants below and above their critical micelle concentrations (CMCs) have been studied at room temperature with the following surfactants: Triton X-100, Triton X-114, Triton X-405, Brij 35, sodium dodecyl sulfate, and cetyltrimethylammonium bromide. While the solubilities of DDT and TCB are greatly enhanced by all surfactants above the measured CMC, DDT also exhibits significant solubility enhancements below the CMC of the molecularly nonhomogeneous surfactants (the Triton series and Brij 35). The plot of the apparent DDT solubility against the concentration of Triton and Brij surfactants shows an uprising curve below the nominal CMC, which is attributed to the successive micellization of the heterogeneous monomer species. Above the CMC, the enhancement effect with the nonionic surfactants is closely proportional to the nonpolar chain content of the surfactant, whereas the effect with the ionic surfactants is less accountable in terms of their nonpolar chain contents. The solubilization power of a micelle relative to a bulk solvent is evaluated by a comparison of the observed micelle-water and solvent-water partition coefficients.

  9. Effects of DDT and BHC on amino acid content and its varieties in Chlorella vulgaris Beij. and Cladophora sp.

    NASA Astrophysics Data System (ADS)

    Lin, Yixiong

    1991-03-01

    In Chlorella vulgaris Beij. and Cladophora sp. treated with different concentrations of r-BHC and p, p-DDT, the protein and free amino acid content in both were higher than those in the controls, and the free amino acid content was even higher than the protein amino acid content.

  10. Effects on wildlife of aerial applications of strobane, DDT, and BHC to tidal marshes in Delaware

    USGS Publications Warehouse

    George, J.L.; Darsie, R.F.; Springer, P.F.

    1957-01-01

    The principal purpose of this study was to ascertain what effect on wildlife, if any, would result from the use of the new insecticide, Strobane, for mosquito control on tideland areas. Comparisons were made with DDT and BHC (43 per cent gamma isomer) commonly used in control operations. The investigation was carried out on the tidal marshes of Bombay Hook National Wildlife Refuge near Smyrna, Delaware. Four areas, all similar in habitat, were chosen-three as test plots for Strobane, BHC, and DDT, respectively, and the fourth as an untreated check. The insecticides in oil solution were applied by airplane at the rates of 0.1, 0.2, and 0.3 pound per acre for gamma isomer of BHC, DDT, and Strobane, respectively. The first application was made on the morning of July 27; and the second, on the evening of August 23, 1955. To assay the results of spraying, 14 testing devices were set up in each area. They consisted of cages, traps, and microscope slides placed in the streams and ponds. The estuarine fishes, Fundulus heteroclitus, Cyprinodon variegatus, Leiostornus xanthurus, and Ailugil curemu; blue crabs, Callinectes sapidus; fiddler crabs, Uca pugnux, Uca minux, and Sesarma reticulaturn; and certain sessile organisms were included in the tests. Analyses of variance on fish and blue crabs showed no significant difference between deaths occurring in treated and control plots, nor among the three treatments. Differential mortalities were suffered by fish caged in streams and ponds. Greater numbers died in the BHC-treated streams and in the DDT-treated ponds. Local concentrations of insecticide appeared to be the cause, although the magnitude of kill was not significantly greater than in control areas. Field observations and crab-pot counts showed that both the fish and blue crabs avoided the sites of high insecticide concentration. Certainly the majority of the free-living individuals in the treated areas were able to survive the sprays, and at the level tested showed no

  11. Effects of five-year DDT application on breeding bird population

    USGS Publications Warehouse

    Robbins, C.S.; Springer, P.F.; Webster, C.G.

    1951-01-01

    Aerial applications of DDT in oil at the rate of 2 pounds per acre applied over a four-year interval on bottomland forest resulted in a 26 percent decrease in the breeding bird population by the fifth spring. The American redstart, parula warbler, and red-eyed vireo suffered decreases of 44 percent, 40. percent, and 28 percent, respectively, over the four-year period. Only the redstart decreased significantly immediately following application of the spray; a few days after the first, second, and fifth annual sprayings an average of 23 percent of redstart territories were deserted. No significant decrease was observed for other species, either immediately following spraying, or over the four-year period.

  12. Effects of phorbol esters on adrenergic receptors of DDT MF-2 smooth muscle cells

    SciTech Connect

    Cowlen, M.; Toews, M.

    1986-03-05

    Phorbol esters have been reported to induce redistribution or internalization of several types of cell surface receptors, including beta-adrenergic receptors (BAR) in some cells. They investigated the effects of phorbol esters on adrenergic receptor distribution in DDT/sub 1/ MF-2 smooth muscle cells in suspension culture. Exposure of cells to epinephrine, an agonist for both BAR and alpha-1 adrenergic receptors (AAR), led to a shift of about half of BAR from plasma membrane to light vesicle fractions on sucrose density gradient centrifugation. This change correlates with other evidence for internalization or sequestration of BAR away from the cell surface. AAR distribution remained unaltered following agonist treatment. Pretreatment of cells with phorbol 12-myristate 13-acetate, which caused about 80% inhibition of epinephrine-stimulated turnover of inositol phospholipids, did not lead to redistribution of either BAR or AAR.

  13. Care, food consumption, and behavior of bald eagles used in DDT tests

    USGS Publications Warehouse

    Chura, N.J.; Stewart, P.A.

    1967-01-01

    Twenty-seven Bald Eagles captured in southeastern Alaska were used in feeding tests to determine the effects of DDT in the diet.....Trapping and housing of eagles are discussed. Various aspects of eagle behavior and handling techniques are also presented. Recommendations are made for preventing injuries and increasing the comfort of captive birds.....The 1962 test birds consumed an average of 274 grams per bird day with a range of 109 to 401 grams per day between birds. Average food intake was 254 grams per bird day for the 1963 test birds with a range of 194 to 324 grams per day between birds.....Weight losses varied from 23 to 49 per cent of normal body weight for the 7 birds which died in the 1962 tests. Tremors and death occurred first for birds on the highest dosage and progressively later for birds on the lower dosages.

  14. Dietary Exposure of Fathead Minnows to the Explosives TNT and RDX and to the Pesticide DDT using Contaminated Invertebrates

    PubMed Central

    Houston, Jerre G.; Lotufo, Guilherme R.

    2005-01-01

    Explosive compounds have been released into the environment during manufacturing, handling, and usage procedures. These compounds have been found to persist in the environment and potentially promote detrimental biological effects. The lack of research on bioaccumulation and bioconcentration and especially dietary transfer on aquatic life has resulted in challenges in assessing ecological risks. The objective of this study was to investigate the potential trophic transfer of the explosive compounds 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) using a realistic freshwater prey/predator model and using dichlorodiphenyltrichloroethane (DDT), a highly bioaccumulative compound, to establish relative dietary uptake potential. The oligochaete worm Lumbriculus variegatus was exposed to 14C-labeled TNT, RDX or DDT for 5 hours in water, frozen in meal-size packages and subsequently fed to individual juvenile fathead minnows (Pimephales promelas). Fish were sampled for body residue determination on days 1, 2, 3, 4, 7, and 14 following an 8-hour gut purging period. Extensive metabolism of the parent compound in worms occurred for TNT but not for RDX and DDT. Fish body residue remained relatively unchanged over time for TNT and RDX, but did not approach steady-state concentration for DDT during the exposure period. The bioaccumulation factor (concentration in fish relative to concentration in worms) was 0.018, 0.010, and 0.422 g/g for TNT, RDX and DDT, respectively, confirming the expected relatively low bioaccumulative potential for TNT and RDX through the dietary route. The experimental design was deemed successful in determining the potential for trophic transfer of organic contaminants via a realistic predator/prey exposure scenario. PMID:16705829

  15. Dietary exposure of fathead minnows to the explosives TNT and RDX and to the pesticide DDT using contaminated invertebrates.

    PubMed

    Houston, Jerre G; Lotufo, Guilherme R

    2005-08-01

    Explosive compounds have been released into the environment during manufacturing, handling, and usage procedures. These compounds have been found to persist in the environment and potentially promote detrimental biological effects. The lack of research on bioaccumulation and bioconcentration and especially dietary transfer on aquatic life has resulted in challenges in assessing ecological risks. The objective of this study was to investigate the potential trophic transfer of the explosive compounds 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) using a realistic freshwater prey/predator model and using dichlorodiphenyltrichloroethane (DDT), a highly bioaccumulative compound, to establish relative dietary uptake potential. The oligochaete worm Lumbriculus variegatus was exposed to 14C-labeled TNT, RDX or DDT for 5 hours in water, frozen in meal-size packages and subsequently fed to individual juvenile fathead minnows (Pimephales promelas). Fish were sampled for body residue determination on days 1, 2, 3, 4, 7, and 14 following an 8-hour gut purging period. Extensive metabolism of the parent compound in worms occurred for TNT but not for RDX and DDT. Fish body residue remained relatively unchanged over time for TNT and RDX, but did not approach steady-state concentration for DDT during the exposure period. The bioaccumulation factor (concentration in fish relative to concentration in worms) was 0.018, 0.010, and 0.422 g/g for TNT, RDX and DDT, respectively, confirming the expected relatively low bioaccumulative potential for TNT and RDX through the dietary route. The experimental design was deemed successful in determining the potential for trophic transfer of organic contaminants via a realistic predator/prey exposure scenario. PMID:16705829

  16. Immunosuppressive Effects of Triclosan, Nonylphenol, and DDT on Human Natural Killer Cells In Vitro

    PubMed Central

    Udoji, Felicia; Martin, Tamara; Etherton, Rachel; Whalen, Margaret M.

    2010-01-01

    Human natural killer (NK) cells are a first line immune defense against tumor cells and virally infected cells. If their function is impaired, it leaves an individual more susceptible to cancer development or viral infection. The ability of compounds that contaminate the environment to suppress the function of NK cells could contribute to increased risk of cancer development. There are a wide spectrum of compounds that significantly contaminate water and food that is consumed by humans leading to accumulation of some of these compounds in human tissues. In the current study, we examined the ability of three such compounds to diminish the function of human NK cells. Triclosan (TC) is an antimicrobial agent used in a large number of antibacterial soaps. Nonylphenol (NP) is a degradation product of compounds used as surfactants and as stabilizers in plastics. 4, 4′-dichlorodiphenyltrichloroethane (DDT) is a pesticide that is mainly used to control mosquitoes. The compounds were examined for their ability to suppress NK function following exposures of 1 hr, 24 hr, 48 hr, and 6 d. Each agent was able to substantially decrease NK lytic function within 24 hr. At a concentration of 5 μM, both TC and NP inhibited NK lytic function by 87 and 30%, respectively; DDT decreased function by 55% at 2.5 μM. The negative effects of each of these compounds persisted and/or intensified following a brief (1 hr) exposure to the compounds, indicating that the impairment of function cannot be eliminated by removal of the compound under in vitro conditions. PMID:20297919

  17. Immunosuppressive effects of triclosan, nonylphenol, and DDT on human natural killer cells in vitro.

    PubMed

    Udoji, Felicia; Martin, Tamara; Etherton, Rachel; Whalen, Margaret M

    2010-01-01

    Human natural killer (NK) cells are a first-line immune defense against tumor cells and virally-infected cells. If their function is impaired, it leaves an individual more susceptible to cancer development or viral infection. The ability of compounds that contaminate the environment to suppress the function of NK cells could contribute to the increased risk of cancer development. There are a wide spectrum of compounds that significantly contaminate water and food that are consumed by humans, leading to accumulation of some of these compounds in human tissues. In the current study, we examined the ability of three such compounds to diminish the function of human NK cells. Triclosan (TC) is an antimicrobial agent used in a large number of antibacterial soaps. Nonylphenol (NP) is a degradation product of compounds used as surfactants and as stabilizers in plastics. 4,4'-Dichlorodiphenyltrichloroethane (DDT) is a pesticide that is mainly used to control mosquitoes. The compounds were examined for their ability to suppress NK function following exposures of 1 h, 24 h, 48 h, and 6 days. Each agent was able to substantially decrease NK lytic function within 24 h. At a concentration of 5 microM, both TC and NP inhibited NK lytic function by 87 and 30%, respectively; DDT decreased function by 55% at 2.5 microM. The negative effects of each of these compounds persisted and/or intensified following a brief (1 h) exposure to the compounds, indicating that the impairment of function cannot be eliminated by removal of the compound under in vitro conditions. PMID:20297919

  18. Synthesis Of Labeled Metabolites

    DOEpatents

    Martinez, Rodolfo A.; Silks, III, Louis A.; Unkefer, Clifford J.; Atcher, Robert

    2004-03-23

    The present invention is directed to labeled compounds, for example, isotopically enriched mustard gas metabolites including: [1,1',2,2'-.sup.13 C.sub.4 ]ethane, 1,1'-sulfonylbis[2-(methylthio); [1,1',2,2'-.sup.13 C.sub.4 ]ethane, 1-[[2-(methylsulfinyl)ethyl]sulfonyl]-2-(methylthio); [1,1',2,2'-.sup.13 C.sub.4 ]ethane, 1,1'-sulfonylbis[2-(methylsulfinyl)]; and, 2,2'-sulfinylbis([1,2-.sup.13 C.sub.2 ]ethanol of the general formula ##STR1## where Q.sup.1 is selected from the group consisting of sulfide (--S--), sulfone (--S(O)--), sulfoxide (--S(O.sub.2)--) and oxide (--O--), at least one C* is .sup.13 C, X is selected from the group consisting of hydrogen and deuterium, and Z is selected from the group consisting of hydroxide (--OH), and --Q.sup.2 --R where Q.sup.2 is selected from the group consisting of sulfide (--S--), sulfone(--S(O)--), sulfoxide (--S(O.sub.2)--) and oxide (--O--), and R is selected from the group consisting of hydrogen, a C.sub.1 to C.sub.4 lower alkyl, and amino acid moieties, with the proviso that when Z is a hydroxide and Q.sup.1 is a sulfide, then at least one X is deuterium.

  19. Persistence of organochlorine chemical residues in fish from the Tombigbee River (Alabama, USA): Continuing risk to wildlife from a former DDT manufacturing facility.

    PubMed

    Hinck, Jo Ellen; Norstrom, Ross J; Orazio, Carl E; Schmitt, Christopher J; Tillitt, Donald E

    2009-02-01

    Organochlorine pesticide and total polychlorinated biphenyl (PCB) concentrations were measured in largemouth bass from the Tombigbee River near a former DDT manufacturing facility at McIntosh, Alabama. Evaluation of mean p,p'- and o,p'-DDT isomer concentrations and o,p'- versus p,p'-isomer proportions in McIntosh bass indicated that DDT is moving off site from the facility and into the Tombigbee River. Concentrations of p,p'-DDT isomers in McIntosh bass remained unchanged from 1974 to 2004 and were four times greater than contemporary concentrations from a national program. Total DDT in McIntosh bass exceeded dietary effect concentrations developed for bald eagle and osprey. Hexachlorobenzene, PCBs, and toxaphene concentrations in bass from McIntosh also exceeded thresholds to protect fish and piscivorous wildlife. Whereas concentrations of DDT and most other organochlorine chemicals in fish have generally declined in the U.S. since their ban, concentrations of DDT in fish from McIntosh remain elevated and represent a threat to wildlife. PMID:18851891

  20. Persistence of organochlorine chemical residues in fish from the Tombigbee River (Alabama, USA): Continuing risk to wildlife from a former DDT manufacturing facility

    USGS Publications Warehouse

    Hinck, J.E.; Norstrom, R.J.; Orazio, C.E.; Schmitt, C.J.; Tillitt, D.E.

    2009-01-01

    Organochlorine pesticide and total polychlorinated biphenyl (PCB) concentrations were measured in largemouth bass from the Tombigbee River near a former DDT manufacturing facility at McIntosh, Alabama. Evaluation of mean p,p???- and o,p???-DDT isomer concentrations and o,p???- versus p,p???-isomer proportions in McIntosh bass indicated that DDT is moving off site from the facility and into the Tombigbee River. Concentrations of p,p???-DDT isomers in McIntosh bass remained unchanged from 1974 to 2004 and were four times greater than contemporary concentrations from a national program. Total DDT in McIntosh bass exceeded dietary effect concentrations developed for bald eagle and osprey. Hexachlorobenzene, PCBs, and toxaphene concentrations in bass from McIntosh also exceeded thresholds to protect fish and piscivorous wildlife. Whereas concentrations of DDT and most other organochlorine chemicals in fish have generally declined in the U.S. since their ban, concentrations of DDT in fish from McIntosh remain elevated and represent a threat to wildlife.

  1. Macrophage migration inhibitory factor (MIF) family in arthropods: Cloning and expression analysis of two MIF and one D-dopachrome tautomerase (DDT) homologues in mud crabs, Scylla paramamosain.

    PubMed

    Huang, Wen-Shu; Duan, Li-Peng; Huang, Bei; Wang, Ke-Jian; Zhang, Cai-Liang; Jia, Qin-Qin; Nie, Pin; Wang, Tiehui

    2016-03-01

    The macrophage migration inhibitory factor (MIF) family, consisting of MIF and D-dopachrome tautomerase (DDT) in vertebrates, is evolutionarily ancient and has been found across Kingdoms including vertebrates, invertebrates, plants and bacteria. The mammalian MIF family are chemokines at the top of the inflammatory cascade in combating infections. They also possess enzymatic activities, e.g. DDT catalysis results in the production of 5,6-dihydroxyindole (DHI), a precursor of eumelanin. MIF-like genes are widely distributed, but DDT-like genes have only been described in vertebrates and a nematode. In this report, we cloned a DDT-like gene, for the first time in arthropods, and a second MIF in mud crab. The mud crab MIF family have a three exon/two intron structure as seen in vertebrates. The identification of a DDT-like gene in mud crab and other arthropods suggests that the separation of MIF and DDT preceded the divergence of protostomes and deuterostomes. The MIF family is differentially expressed in tissues of adults and during embryonic development and early life. The high level expression of the MIF family in immune tissues, such as intestine and hepatopancreas, suggests an important role in mud crab innate immunity. Mud crab DDT is highly expressed in early embryos, in megalops and crablets and this coincides with the requirement for melanisation in egg chorion tanning and cuticular hardening in arthropods, suggesting a potential novel role of DDT in melanogenesis via its tautomerase activity to produce DHI in mud crab. The clarification of the presence of both MIF and DDT in this report paves the way for further investigation of their functional roles in immunity and in melanogenesis in mud crab and other arthropods. PMID:26826424

  2. Low Concentrations of o,p’-DDT Inhibit Gene Expression and Prostaglandin Synthesis by Estrogen Receptor-Independent Mechanism in Rat Ovarian Cells

    PubMed Central

    Liu, Jing; Zhao, Meirong; Zhuang, Shulin; Yang, Yan; Yang, Ye; Liu, Weiping

    2012-01-01

    o,p’-DDT is an infamous xenoestrogen as well as a ubiquitous and persistent pollutant. Biomonitoring studies show that women have been internally exposed to o,p’-DDT at range of 0.3–500 ng/g (8.46×10−10 M−1.41×10−6 M) in blood and other tissues. However, very limited studies have investigated the biological effects and mechanism(s) of o,p’-DDT at levels equal to or lower than current exposure levels in human. In this study, using primary cultures of rat ovarian granulosa cells, we determined that very low doses of o,p’-DDT (10−12−10−8 M) suppressed the expression of ovarian genes and production of prostaglandin E2 (PGE2). In vivo experiments consistently demonstrated that o,p’-DDT at 0.5–1 mg/kg inhibited the gene expression and PGE2 levels in rat ovary. The surprising results from the receptor inhibitors studies showed that these inhibitory effects were exerted independently of either classical estrogen receptors (ERs) or G protein-coupled receptor 30 (GPR30). Instead, o,p’-DDT altered gene expression or hormone action via inhibiting the activation of protein kinase A (PKA), rather than protein kinase C (PKC). We further revealed that o,p’-DDT directly interfered with the PKA catalytic subunit. Our novel findings support the hypothesis that exposure to low concentrations of o,p’-DDT alters gene expression and hormone synthesis through signaling mediators beyond receptor binding, and imply that the current exposure levels of o,p’-DDT observed in the population likely poses a health risk to female reproduction. PMID:23209616

  3. Low concentrations of o,p'-DDT inhibit gene expression and prostaglandin synthesis by estrogen receptor-independent mechanism in rat ovarian cells.

    PubMed

    Liu, Jing; Zhao, Meirong; Zhuang, Shulin; Yang, Yan; Yang, Ye; Liu, Weiping

    2012-01-01

    o,p'-DDT is an infamous xenoestrogen as well as a ubiquitous and persistent pollutant. Biomonitoring studies show that women have been internally exposed to o,p'-DDT at range of 0.3-500 ng/g (8.46×10(-10) M-1.41×10(-6) M) in blood and other tissues. However, very limited studies have investigated the biological effects and mechanism(s) of o,p'-DDT at levels equal to or lower than current exposure levels in human. In this study, using primary cultures of rat ovarian granulosa cells, we determined that very low doses of o,p'-DDT (10(-12)-10(-8) M) suppressed the expression of ovarian genes and production of prostaglandin E2 (PGE2). In vivo experiments consistently demonstrated that o,p'-DDT at 0.5-1 mg/kg inhibited the gene expression and PGE2 levels in rat ovary. The surprising results from the receptor inhibitors studies showed that these inhibitory effects were exerted independently of either classical estrogen receptors (ERs) or G protein-coupled receptor 30 (GPR30). Instead, o,p'-DDT altered gene expression or hormone action via inhibiting the activation of protein kinase A (PKA), rather than protein kinase C (PKC). We further revealed that o,p'-DDT directly interfered with the PKA catalytic subunit. Our novel findings support the hypothesis that exposure to low concentrations of o,p'-DDT alters gene expression and hormone synthesis through signaling mediators beyond receptor binding, and imply that the current exposure levels of o,p'-DDT observed in the population likely poses a health risk to female reproduction. PMID:23209616

  4. Effects of nano-sized zero-valent iron (nZVI) on DDT degradation in soil and its toxicity to collembola and ostracods.

    PubMed

    El-Temsah, Yehia S; Joner, Erik J

    2013-06-01

    Nano-sized zero valent iron (nZVI) has been studied for in situ remediation of contaminated soil and ground water. However, little is known about its effects on organisms in soil and aquatic ecosystems. In this study, the effect of nZVI on degradation of DDT and its ecotoxicological effects on collembola (Folsomia candida) and ostracods (Heterocypris incongruens) were investigated. Two soils were used in suspension incubation experiments lasting for 7 and 30 d; a spiked (20 mg DDT kg(-1)) sandy soil and an aged (>50 years) DDT-polluted soil (24 mg DDT kg(-1)). These were incubated with 1 or 10 g nZVI kg(-1), and residual toxicity in soil and the aqueous phase tested using ecotoxicological tests with collembola or ostracods. Generally, addition of either concentration of nZVI to soil led to about 50% degradation of DDT in spiked soil at the end of 7 and 30 d incubation, while the degradation of DDT was less in aged DDT-polluted soil (24%). Severe negative effects of nZVI were observed on both test organisms after 7 d incubation, but prolonged incubation led to oxidation of nZVI which reduced its toxic effects on the tested organisms. On the other hand, DDT had significant negative effects on collembolan reproduction and ostracod development. We conclude that 1 g nZVI kg(-1) was efficient for significant DDT degradation in spiked soil, while a higher concentration was necessary for treating aged pollutants in soil. The adverse effects of nZVI on tested organisms seem temporary and reduced after oxidation. PMID:23522781

  5. [Influence of the interaction between iron oxide and electron donor substances on 1,1,1-trichloro- 2, 2-bis (p-chlorophenyl) ethane ( DDT) reductive dechlorination in hydragric acrisols].

    PubMed

    Liu, Cui-Ying; Xu, Xiang-Hua; Wang, Zhuang; Yao, Tong-Yan

    2014-11-01

    The interaction between iron oxide and electron donor substance have significant influences on electron transfer and the growth of iron-reducing bacteria, which may affect the reductive dechlorination of polychlorinated organic compounds in soil. Anaerobic soil incubation experiment was conducted to study the effect and its mechanism of iron oxide (goethite), electron donor substances (butyrate and ethanol), and their interaction on DDT reductive dechlorination in Hydragric Acrisols. Results showed that after 6 weeks of anaerobic incubation, the extractable residues of DDT were between 1.29% and 2.01% of initial DDT amounts in soils, which was attributed to the dechlorinated degradation of DDT and formation of bound residues of DDT and its dechlorinated products. The main product of DDT anaerobic dechlorination was 1,1-dichloro-2,2-bis (p-chloro-phenyl) ethane (DDD). During the prophase of incubation, the application of butyrate or ethanol led to the decreased pH and increased Eh for reaction system, thus inhibited DDT dechlorination. The applications of only goethite or goethite and electron donor substances resulted in the increased soil pH, decreased soil Eh and increased Fe( II ) contents, thus accelerated DDT dechlorination. There was no significant interaction between butyrate and iron oxide on DDT dechlorination, whereas there was antagonistic action between ethanol and iron oxide on DDT dechlorination. The results will be of great significance for developing efficient and in-situ remediation technology of DDT contaminated soil. PMID:25639109

  6. [The effect of long-term exposure to low doses of endocrine disruptor ddt on serum levels of thyroid protein autoantigenes and antithyroid autoantibodies].

    PubMed

    Yaglova, N V; Yaglov, V V

    2016-01-01

    Changes in secretion of thyroid autoantigenes and production of antithyroid autoantibodies after long-term exposure to low doses of DDT were studied. Changes in serum levels of antithyroid peroxidase antibodies and thyroid peroxidase, attributed to disruption of thyroxine production by DDT were found. Long-term exposure of rats to low doses of DDT revealed no specific impact on serum autoantibodies to all thyroid autoantigenes studied. The increase of the ratio of autoantibody/autoantigen for thyroid peroxidase and thyroglobulin was rather small and thus could not be considered as a significant symptom of thyroid autoimmunity. PMID:26973191

  7. A histology-based fish health assessment of the tigerfish, Hydrocynus vittatus from a DDT-affected area

    NASA Astrophysics Data System (ADS)

    McHugh, K. J.; Smit, N. J.; Van Vuren, J. H. J.; Van Dyk, J. C.; Bervoets, L.; Covaci, A.; Wepener, V.

    The Pongolapoort Dam (PPD) in the Phongola River, Kwa-Zulu Natal, South Africa and the surrounding area are classified as intermediate to low risk malaria areas and are continually being treated with DDT for malaria vector control. DDT is known as an endocrine disrupting chemical posing estrogenic and anti-androgenic properties and therefore might impact on the health of the 18 freshwater fish species found within this system. Of these species the tigerfish, Hydrocynus vittatus, is targeted by both recreational and local subsistence fishermen and was recently included in the South African threatened or protected species list. Their protected status and importance as a food source therefore emphasises the need for their health status elucidation. Previous research on H. vittatus in the Phongola floodplain highlighted DDT biomagnification in this species. Recent data show that the sum of the DDT levels in February 2009 (5403.9 ng/g lipid) and July 2009 (5537.4 ng/g lipid) is still comparable to the high levels found 30 years earlier. The aim of the current study was thus to determine the health status of H. vittatus in relation to DDT exposure by means of a histology-based fish health assessment protocol. Tigerfish were collected in February 2009 ( n = 30) and July 2009 ( n = 15) and gill, kidney and liver tissue were subjected to histological analyses. Mean Index values showed that the Kidney Index ( IK), Gill Index ( IG) and Fish Index ( IFISH) were higher in fish from the February survey while the Liver Index was higher in those collected during July. Liver alterations identified included intercellular oedema, granular degeneration, vacuolation, nuclear pleomorphism and lymphocyte infiltration. Kidney alterations included dilation of the glomerulus capillaries, vacuolation and hyaline droplet degeneration. Gill alterations identified included telangiectasia and hyperplasia of the secondary lamella, congestion, and rupture of pillar cells. Although histological

  8. Entomological and parasitological impacts of indoor residual spraying with DDT, alphacypermethrin and deltamethrin in the western foothill area of Madagascar

    PubMed Central

    2014-01-01

    Background In Madagascar, indoor residual spraying (IRS) with insecticide was part of the national malaria control programme since the middle of the twentieth century. It was mainly employed in the highlands and the foothill areas, which are prone to malaria epidemics. Prior to a policy change foreseeing a shift from DDT to pyrethroids, a study was carried out to assess the entomological and parasitological impacts of IRS in areas with DDT or pyrethroids and in areas without IRS. Methods The study was carried out from October 2002 to February 2005 in three communes of the western foothill area of Madagascar. Two communes received IRS with DDT in February 2003, then IRS with pyrethroids (alphacypermethrin or deltamethrin) in February 2004. The third commune remained untreated. Mosquitoes were collected at night using human landing catches and early in the morning in resting places. Blood smears were obtained from schoolchildren and microscopically examined for Plasmodium presence. Results In total, 18,168 human landing mosquitoes and 12,932 resting anophelines were collected. The Anopheles species caught comprised 10 species. The main and most abundant malaria vector was Anopheles funestus (72.3% of human-seeking malaria vectors caught indoors). After IRS had taken place, this species exhibited a lower human biting rate and a lower sporozoite index. Overall, 5,174 blood smears were examined with a mean plasmodic index of 19.9%. A total of four Plasmodium species were detected. Amongst tested school children the highest plasmodial index was 54.6% in the untreated commune, compared to 19.9% in the commune sprayed with DDT and 11.9% in the commune sprayed with pyrethroid. The highest prevalence of clinical malaria attacks in children present at school the day of the survey was 33% in the untreated commune compared to 8% in the areas which received IRS. Conclusion In terms of public health, the present study shows (1) a high efficacy of IRS with insecticide, (2) a

  9. Mutations in DIIS5 and the DIIS4-S5 linker of Drosophila melanogaster sodium channel define binding domains for pyrethroids and DDT.

    PubMed

    Usherwood, P N R; Davies, T G E; Mellor, I R; O'Reilly, A O; Peng, F; Vais, H; Khambay, B P S; Field, L M; Williamson, M S

    2007-11-27

    Mutations in the DIIS4-S5 linker and DIIS5 have identified hotspots of pyrethroid and DDT interaction with the Drosophila para sodium channel. Wild-type and mutant channels were expressed in Xenopus oocytes and subjected to voltage-clamp analysis. Substitutions L914I, M918T, L925I, T929I and C933A decreased deltamethrin potency, M918T, L925I and T929I decreased permethrin potency and T929I, L925I and I936V decreased fenfluthrin potency. DDT potency was unaffected by M918T, but abolished by T929I and reduced by L925I, L932F and I936V, suggesting that DIIS5 contains at least part of the DDT binding domain. The data support a computer model of pyrethroid and DDT binding. PMID:17991435

  10. EVALUATION OF A FIRST-ORDER MODEL FOR THE PREDICTION OF THE BIOACCUMULATION OF PCBS AND DDT FROM SEDIMENT INTO THE MARINE DEPOSIT-FEEDING CLAM MACOMA NASUTA

    EPA Science Inventory

    A first-order model for predicting contaminant bioaccumulation from sediments into benthic invertebrates was validated using a marine deposit-feeding clam, Macoma nasuta, exposed to polychlorobiphenyl (PCB)-spiked and dichlorodiphenyltrichloroethane (DDT)-contaminated sediments. ...

  11. Environmental exposure and lifestyle predictors of lead, cadmium, PCB, and DDT levels in Great Lakes fish eaters

    SciTech Connect

    Hovinga, M.E.; Sowers, M.; Humphrey, H.E. )

    1993-03-01

    A previously characterized cohort of 115 Great Lakes fish eaters and 95 non-fish-eating regional controls was reexamined in 1989. Levels of blood lead and cadmium and serum PCB and DDT were measured. Lifestyle characteristics, including recent and historic fish consumption, were evaluated as predictors of contaminant levels using multivariate regression analysis. Significantly elevated serum PCB and DDT levels were observed in fish eaters, compared with controls. Historic fish consumption, rather than recent consumption, was identified as the primary predictor of current serum levels. Mean blood lead and cadmium were also significantly higher in fish eaters than in controls. However, the primary predictors of lead and cadmium were behavioral exposures--specifically smoking and self-reported occupational and recreational exposure-rather than fish consumption. These findings illustrate the importance of evaluating a variety of possible sources when investigating human exposure to environmental contaminants.

  12. Spatio-Temporal Patterns in kdr Frequency in Permethrin and DDT Resistant Anopheles gambiae s.s. from Uganda

    PubMed Central

    Verhaeghen, Katrijn; Bortel, Wim Van; Roelants, Patricia; Okello, Paul Edward; Talisuna, Ambrose; Coosemans, Marc

    2010-01-01

    The planned upscaling of vector control strategies requires insight into the epidemiological consequences of vector resistance. Therefore, the pyrethroid and DDT resistance status of Anopheles gambiae s.l. was assessed in Uganda from 2004 to 2006, and spatial and seasonal variations in knockdown resistance (kdr) frequencies were analyzed in terms of epidemiological significance. Anopheles gambiae s.l. was DDT and pyrethroid resistant in central and eastern Uganda. The L1014S kdr allele frequencies varied from 3% to 48% in An. gambiae s.s. Although the homozygous resistant genotype was the most prevalent genotype among survivors, the genotypes could not entirely explain the bioassay results. In the dry season, the kdr frequency was significantly higher in Plasmodium falciparum-infected mosquitoes, indicating that mosquitoes bearing a kdr mutation have a better adult survival, hence a higher likelihood of becoming infectious. This study showed that kdr might have an epidemiological impact that could jeopardize the vector control strategies. PMID:20348500

  13. Acute toxicity of chromate, DDT, PCP, TPBS, and zinc to Daphnia magna cultured in hard and soft water

    SciTech Connect

    Berglind, R.; Dave, G.

    1984-07-01

    The aim of this study was to compare the toxicity of five chemicals to water fleas (Daphnia magna) cultured in either hard to soft water. The toxicity tests were made in reconstituted waters and the five chemicals to be tested were, p,p'-DDT, pentachlorophenol (PCP), tetrapropylenbenzyl sulfonate (TPBS), potassium bichromate (K/sub 2/Cr/sub 2/O/sub 7/) and zincsulfate (ZnSO/sub 4/ x 7H/sub 2/O).

  14. Effects of selected food phytochemicals in reducing the toxic actions of TCDD and p,p′-DDT in U937 macrophages

    PubMed Central

    Sciullo, Eric M.; Vogel, Christoph F.; Wu, Dalei; Murakami, Akira; Ohigashi, Hajime

    2010-01-01

    To assess the effectiveness of selected food phytochemicals in reducing the toxic effects of the environmental toxicants, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and p,p′-DDT (DDT), we tested the potencies of auraptene, nobiletin, zerumbone, and (±)-13-hydroxy-10-oxo-trans-11-octadecenoic acid (13-HOA) in reversing the inflammatory action of these toxicants in U937 human macrophages. Using quantitative RT–PCR as the initial screening assay, we identified antagonistic actions of zerumbone and auraptene against the action of TCDD and DDT in up-regulating the mRNA expressions of COX-2 and VEGF. The functional significance of the inhibitory action of zerumbone on COX-2 expression was confirmed by demonstrating its suppression of TCDD-induced activation of COX-2 gene expression in mouse MMDD1 cells. We tested auraptene on DDT-induced reactive oxygen species (ROS) formation in U937 macrophages and found that auraptene is a powerful agent antagonizing this action of DDT. To confirm the significance of these actions of zerumbone and auraptene at the cellular level, we assessed their influence on TCDD-induced apoptosis resistance in intact U937 macrophages and found that they are capable of reversing this action of TCDD. In conclusion, zerumbone and auraptene were identified to be the most effective agents in protecting U937 macrophages from developing these cell toxic effects of TCDD and DDT. PMID:20865247

  15. Effects of soil oxygen conditions and soil pH on remediation of DDT-contaminated soil by laccase from white rot fungi.

    PubMed

    Zhao, Yuechun; Yi, Xiaoyun

    2010-04-01

    High residues of DDT in agricultural soils are of concern because they present serious threats to food security and human health. This article focuses on remediation of DDT-contaminated soil using laccase under different soil oxygen and soil pH conditions. The laboratory experiment results showed significant effects of soil oxygen conditions and soil pH on remediation of DDT-contaminated soil by laccase at the end of a 25-d incubation period. This study found the positive correlation between the concentration of oxygen in soil and the degradation of DDT by laccase. The residue of DDTs in soil under the atmosphere of oxygen decreased by 28.1% compared with the atmosphere of nitrogen at the end of the incubation with laccase. A similar pattern was observed in the remediation of DDT-contaminated soil by laccase under different flooding conditions, the higher the concentrations of oxygen in soil, the lower the residues of four DDT components and DDTs in soils. The residue of DDTs in the nonflooding soil declined by 16.7% compared to the flooded soil at the end of the incubation. The residues of DDTs in soils treated with laccase were lower in the pH range 2.5-4.5. PMID:20617049

  16. Violent cookoff reactions in HMX-based explosives in DDT tubes: Tracking luminous waves with streak imaging

    NASA Astrophysics Data System (ADS)

    Parker, Gary; Dickson, Peter; Asay, Blaine W.; Smilowitz, Laura; Henson, Bryan; McAfee, John

    2012-03-01

    Recent implementation of modern high-speed video cameras has permitted the experimental flexibility needed to revisit classic deflagration-to-detonation (DDT) tube experiments and capture novel and valuable results displaying the progression of luminous reaction from a cookoff event. The authors present select data from a series of experiments where the HMX-based high explosives PBX 9501 and LX-07 were heated above 180°C for various durations to impose damage (i.e. phase transitions and void generation) before being driven to cook off. These two explosives have different polymeric binders, HMX mass fractions and cook off responses and a comparison between the two offers mechanistic insights on how thermal explosions evolve. From this series, results will be displayed indicating a wide range of violence from somewhat mild pressure bursts, to intermediate power compressive burns, to high-violence DDT. Image data from high temperature DDT tube experiments, where the explosive was ignited on one end, were also collected and will be included for comparison.

  17. Comparison of dieldrin, lindane, and DDT extractions from serum, and gas-liquid chromatography using glass capillary columns.

    PubMed

    Franken, J J; Luyten, B J

    1976-11-01

    Rats were given an oral dose of 14C-labeled chlorinated pesticides to obtain serum containing p,p'-DDT, dieldrin, or lindane. Simple hexane and formic acid-hexane extraction methods, involving pretreatment of the serum with formic acid, were compared by radiometric and by paper chromatographic and gas chromatographic analysis. In vivo binding of chlorinated pesticides to constituents of the serum does not necessarily prohibit their isolation by simple hexane extractions, provided that the extraction is very vigorous and at least 5 min long. Stable emulsions were broken by cooling in liquid nitrogen or Dry Ice-acetone. The hexane extraction method described yields quantitative recovery of the pesticides studied, whereas the formic acid-hexane method is quantitative for p,p'-DDT, 93% for dieldrin, and 89% for lindane. Gas chromatographic comparison of both methods, using human serum, shows that the hexane method extracts 16% more beta-BHC, 7% more dieldrin and HCB, and 4% more p,p'-DDE from serum than does the formic acid-hexane method. The difference for p,p'-DDT is not significant. Gas chromatography with glass capillary columns and an all-glass solids injection system yielded detection limits as low as 15 fg. Data show that the use of an internal standard considerably improves the precision of quantitation. PMID:62748

  18. The insecticide 1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane (DDT) alters the membrane raft location of the TSH receptor stably expressed in Chinese hamster ovary cells

    SciTech Connect

    De Gregorio, Francesca; Pellegrino, Mario; Picchietti, Simona; Belardinelli, Maria C.; Taddei, Anna Rita; Fausto, Anna Maria; Rossi, Mario; Maggio, Roberto; Giorgi, Franco

    2011-06-01

    DDT is a highly lipophilic molecule known to deplete membrane rafts of their phosphoglycolipid and cholesterol contents. However, we have recently shown that DDT can also alter the thyroid homeostasis by inhibiting TSH receptor (TSHr) internalization. The present study was undertaken to verify whether DDT goitrogenic effects are due to the insecticide acting directly on TSHr or via alteration of the membrane rafts hosting the receptor itself. Our results demonstrate that, in CHO-TSHr transfected cells, TSHr is activated in the presence of TSH, while it is inhibited following DDT exposure. DDT can also reduce the endocytic vesicular traffic, alter the extension of multi-branched microvilli along their plasma membranes and induce TSHr shedding in vesicular forms. To verify whether TSHr displacement might depend on DDT altering the raft constitution of CHO-TSHr cell membranes the extent of TSHr and lipid raft co-localization was examined by confocal microscopy. Evidence shows that receptor/raft co-localization increased significantly upon exposure to TSH, while receptors and lipid rafts become dislodged on opposite cell poles in DDT-exposed CHO-TSHr cells. As a control, under similar culturing conditions, diphenylethylene, which is known to be a lipophilic substance that is structurally related to DDT, did not affect the extent of TSHr and lipid raft co-localization in CHO-TSHr cells treated with TSH. These findings corroborate and extend our view that, in CHO cells, the DDT disrupting action on TSHr is primarily due to the insecticide acting on membranes to deplete their raft cholesterol content, and that the resulting inhibition on TSHr internalization is due to receptor dislodgement from altered raft microdomains of the plasma membrane. - Highlights: >DDT is a pesticide with a severe environmental impact >Epidemiologic correlation exists between exposition to DDT and thyroid dysfunction >DDT is a lipophilic molecule that has been shown to inhibit TSH receptor

  19. Toxicological significance of dihydrodiol metabolites

    SciTech Connect

    Hsia, M.T.

    1982-01-01

    Dihydrodiols are often found as the major organic-extractable metabolites of various olefinic or aromatic xenobiotics in many biological samples. Studies on the chemistry of dihydrodiol metabolites have provided insight into the pharmacokinetic behavior and the mode of action of the parent compound. The toxicology of dihydrodiol is more complex than what can be deduced solely on the basis of diminished bioavailability of the epoxide precursor, and the increased hydrophilicity associated with the dihydrodiol moiety. Dihydrodiols can be intrinsically toxic and may even represent metabolically activated species. Some of the dihydrodiol metabolites may still retain sufficient lipophilic character to serve again as substrates for microsomal oxygenases. Because of the tremendous chemical and biological diversity that existed among the various dihydrodiols, more mechanistic studies are needed to examine the toxicological properties of these compounds. It may be premature to conclude dihydrodiol formation as purely a detoxification route for xenobioties.

  20. Deleterious effects of reactive metabolites

    PubMed Central

    2010-01-01

    A number of drugs have been withdrawn from the market or severely restricted in their use because of unexpected toxicities that become apparent only after the launch of new drug entities. Circumstantial evidence suggests that, in most cases, reactive metabolites are responsible for these unexpected toxicities. In this review, a general overview of the types of reactive metabolites and the consequences of their formation are presented. The current approaches to evaluate bioactivation potential of new compounds with particular emphasis on the advantages and limitation of these procedures will be discussed. Reasonable reasons for the excellent safety record of certain drugs susceptible to bioactivation will also be explored and should provide valuable guidance in the use of reactive-metabolite assessments when nominating drug candidates for development. This will, in turn, help us to design and bring safer drugs to the market. PMID:20972370

  1. Breast milk excretion Kinetic of b-HCH, pp'DDE and pp'DDT.

    PubMed

    Waliszewski, S M; Melo-Santiesteban, G; Villalobos-Pietrini, R; Gómez-Arroyo, S; Amador-Muñoz, O; Herrero-Mercado, M; Carvajal, O

    2009-12-01

    Breast milk is considered the most important route in the elimination of deposited organochlorine pesticides in a mother’s body. The equilibrium of organochlorine pesticides in the human body considers the elements of internal transport processes, the equilibrium pattern between pesticides and tissue fat contents, and the mobilization of lipids and lipoproteins among body parts. The aim of this study was to determine organochlorine pesticide levels in breast milk samples from the 4th to the 30th day of lactation and the trend in their concentration time so as to forecast the time tendency of residue levels and the pesticide excretion pattern. Milk samples were taken from forty participants and analyzed by GLC-ECD. The organochlorine pesticide residues determined in the breast milk samples during lactation decreased: β-HCH from 0.095 to 0.066 mg/kg, pp′DDE from 1.807 to 1.423 mg/kg and pp′DDT from 0.528 to 0.405 mg/kg, at the characteristic rate for each compound. The obtained results compared with the calculated fits of forecasts were parallel and did not exhibit significant differences. The newborn baby exposed during lactation had organochlorine pesticide residues whose levels decreased permanently. The levels depended not only on the breast milk nutrition, but also on the total environmental exposures which included air pollution as a significant contamination source. PMID:19551328

  2. Allantoinase in lake trout (Salvelinus namaycush): in vitro effects of PCBs, DDT and metals

    USGS Publications Warehouse

    Passino, Dora R. May; Cotant, Carol A.

    1979-01-01

    1. Allantoinase, an enzyme in the purine-urea cycle, was found in livers of Salvelinus namaycush (Osteichthyes: Salmoniformes). 2. The enzyme was active from pH 6.6 to 8.2 at 37°C and from pH 7.4 to 9.0 at 10°C and had an Arrhenius energy of activation of 11.0 kcal/mol and a temperature quotient of 2.0. The Km of the enzyme homogenate was 8.4 mM allantoin. 3. The concentration of inorganic metals at which 50% inhibition occurred during in vitro exposure were 6.0 mg/l Cu2+, 6.7 mg/l Cd2+, 34 mg/l Hg2+ and 52 mg/l Pb2+. The in vitro sensitivity to PCBs, DDT and DDE and kinetics in the presence of metals were determined. 4. Allantoinase activity was negatively correlated with body length for fish from Lake Michigan but not from Lake Superior or the laboratory.

  3. Study of the dehydrochlorination of DDT in basic media in sulfobetaine aqueous micellar solutions

    SciTech Connect

    Rodriguez, A.; Mar Graciani, M. del; Guinda, A.; Munoz, M.; Moya, M.L.

    2000-04-04

    The reaction of dehydrochlorination of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, DDT, with hydroxide ions has been studied in aqueous micellar solutions of N-tetradecyl-N,N-dimethyl-3-ammino-1-propane-sulfonate, SB3-14, and N-hexadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate, SB3-16. A simple expression for the observed rate constant, k{sub obs}, based on the pseudophase model, could explain the influence of changes in the surfactant concentration on k{sub obs}. The kinetic effects of added electrolytes (NaF, NaCl, NaBr, and NaNO{sub 3}) on the reaction rate in SB3-14 micellar media have also been studied. They were rationalized by considering the binding of the anions, which come from the added salt, to the sulfobetaine micelles and their competition with the reactive hydroxide ions for the micellar surface. Conductivity measurements have been a helpful tool in the discussion of the kinetic effects of added salts and permitted the estimation of equilibrium constants for the distribution of the anions between the zwitterionic micelles and the aqueous phase.

  4. Observation and modeling of deflagration-to-detonation (DDT) transition in low-density HMX

    NASA Astrophysics Data System (ADS)

    Tringe, Joseph; Vandersall, Kevin; Reaugh, Jack; Levie, Harold; Henson, Bryan; Smilowitz, Laura; Parker, Gary

    2015-06-01

    We employ simultaneous flash x-ray radiography and streak imaging, together with a multi-phase finite element model, to understand deflagration-to-detonation transition (DDT) phenomena in low-density (~ 1.2 gm/cm3) powder of the explosive cyclotetramethylene-tetranitramine (HMX). HMX powder was lightly hand-tamped in a 12.7 mm diameter column, relatively lightly-confined in an optically-transparent polycarbonate cylinder with wall thickness 25.4 mm. We observe apparent compaction of the powder in advance of the detonation transition, both by x-ray contrast and by the motion of small steel spheres pre-emplaced throughout the length of explosive. High-speed imaging along the explosive cylinder length provides a temporally continuous record of the transition that is correlated with the high-resolution x-ray image record. Preliminary simulation of these experiments with the HERMES model implemented in the ALE3D code enables improved understanding of the explosive particle burning, compaction and detonation phenomena which are implied by the observed reaction rate and transition location within the cylinder. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  5. Shock induced ignition and DDT in the presence of mechanically driven fluctuations

    NASA Astrophysics Data System (ADS)

    Wang, Wentian; McDonald, James G.; Radulescu, Matei I.

    2015-11-01

    The present study addresses the problem of shock induced ignition and transition to detonation in the presence of mechanical and thermal fluctuations. These departures from a homogeneous medium are of significant importance in practical situations, where such fluctuations may promote hot-spot ignition and favor the flame transition to detonation. The problem is studied in 1D, where a piston-induced shock ignites the gas. The fluctuations in the shock-compressed medium are controlled by allowing the piston's speed to oscillate around a mean, with controllable frequency and amplitude. A Lagrangian numerical formulation is used, which allows to treat exactly the transient boundary condition at the piston head. The hydrodynamic solver is coupled with the reactive dynamics of the gas using Cantera. The code was verified by comparison with steady state ZND solutions and previous shock induced ignition results in homogeneous media. Results obtained for different fuels illustrate the strong relation of the DDT amplification length to mechanical fluctuations in systems with a high effective activation energy and fast rate of energy deposition, consistent with experiments performed on fast flame acceleration in the presence of strong mechanical perturbations. Financial support from NSERC and Shell, with A. Pekalski and M. Levin as technical monitors, are greatly acknowledged.

  6. Effects on wildlife of DDT used for control of Dutch elm disease

    USGS Publications Warehouse

    Benton, A.H.

    1951-01-01

    During the summer of 1949 studies were conducted at Princeton, New Jersey, to determine the effects on wildlife of DDT used in the control of Dutch elm disease. Direct mortality was determined by intensive search for dead birds after spraying. Twenty-six songbirds, one bat, and one gray squirrel were found. Of 11 dead birds from a study area of approximately 20 acres only one was an adult. Songbird populations were determined by censuses before and after spraying on a study area and on a similar unsprayed check area. The number of all breeding birds showed a 19.6 percent decrease on both the study and check areas during the week immediately following spraying. About two weeks after spraying the population in the treated area began to increase and within another week was back to prespray level. When only those species common to both sprayed and unsprayed areas are considered a population decline of 22 percent was measured in the sprayed area while the check area showed a 6 percent increase in numbers over the same period. Nestling mortality was studied in both areas. Among 18 young found on the study area during and following spraying 8 (44%) survived. Death of two broods of catbirds occurred four days after spraying. Of 21 young found on the check area 15 (71%) survived.

  7. Microbial production of primary metabolites

    NASA Astrophysics Data System (ADS)

    Demain, Arnold L.

    1980-12-01

    Microbial production of primary metabolites contributes significantly to the quality of life. Through fermentation, microorganisms growing on inexpensive carbon sources can produce valuable products such as amino acids, nucleotides, organic acids, and vitamins which can be added to food to enhance its flavor or increase its nutritive value. The contribution of microorganisms will go well beyond the food industry with the renewed interest in solvent fermentations. Microorganisms have the potential to provide many petroleum-derived products as well as the ethanol necessary for liquid fuel. The role of primary metabolites and the microbes which produce them will certainly increase in importance.

  8. Sphingolipid metabolites in inflammatory disease

    PubMed Central

    Maceyka, Michael; Spiegel, Sarah

    2015-01-01

    Sphingolipids are ubiquitous building blocks of eukaryotic cell membranes. Progress in our understanding of sphingolipid metabolism, state-of-the-art sphingolipidomic approaches and animal models have generated a large body of evidence demonstrating that sphingolipid metabolites, particularly ceramide and sphingosine-1-phosphate, are signalling molecules that regulate a diverse range of cellular processes that are important in immunity, inflammation and inflammatory disorders. Recent insights into the molecular mechanisms of action of sphingolipid metabolites and new perspectives on their roles in regulating chronic inflammation have been reported. The knowledge gained in this emerging field will aid in the development of new therapeutic options for inflammatory disorders. PMID:24899305

  9. Risk assessment of great horned owls (Bubo virginianus) exposed to polychlorinated biphenyls and DDT along the Kalamazoo River, Michigan, USA.

    PubMed

    Strause, Karl D; Zwiernik, Matthew J; Im, Sook Hyeon; Bradley, Patrick W; Moseley, Pamela P; Kay, Denise P; Park, Cyrus S; Jones, Paul D; Blankenship, Alan L; Newsted, John L; Giesy, John P

    2007-07-01

    The great horned owl (GHO; Bubo virginianus) was used in a multiple lines of evidence study of polychlorinated biphenyls (PCBs) and p,p'-dichlorodiphenyltrichloroethane (DDT) exposures at the Kalamazoo River Superfund Site (KRSS), Kalamazoo, Michigan, USA. The study examined risks from total PCBs, including 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQWorld Health Organization [WHO]-Avian Toxicity Equivalency Factor [TEF]), and total DDTs (sum of DDT, dichlorodiphenyldichloroethylene [DDE], and dichlorodiphenyldichloroethane [DDD]; sigmaDDT) by measuring concentrations in eggs and nestling blood plasma in two regions of the KRSS (upper, lower) and an upstream reference area (RA). An ecological risk assessment compared concentrations of the contaminants of concern (COCs) in eggs or plasma to toxicity reference values. Productivity and relative abundance measures for KRSS GHOs were compared with other GHO populations. Egg shell thickness was measured to assess effects of p,p'-DDE. The concentrations of PCBs in eggs were as great as 4.7 x 10(2) and 4.0 x 10(4) ng PCB/g, wet weight at the RA and combined KRSS sites, respectively. Egg TEQ(WHO-Avian) calculated from aryl hydrocarbon receptor-active PCB congeners and WHO TEFs ranged to 8.0 and 1.9 x 10(2) pg TEQ(WHO-Avian)/g, (wet wt) at the RA and combined KRSS, respectively. Egg sigmaDDT concentrations were as great as 4.2 x 10(2) and 5.0 x 10(3) ng sigmaDDT/g (wet wt) at the RA and combined KRSS, respectively. Hazard quotients (HQs) for the upper 95% confidence interval (UCI) (geometric mean) and least observable adverse effect concentration (LOAEC) for COCs in eggs were < or = 1.0 for all sites. Hazard quotient values based on the no observable adverse effect concentration (NOAEC) 95% UCI in eggs were < or = 1.0, except at the LKRSS (PCB HQ = 3.1; TEQ(WHO-Avian) HQ = 1.3). Productivity and relative abundance measures indicated no population level effects in the UKRSS. PMID:17665678

  10. Residues of DDT in lake trout (Salvelinus namaycush) and coho salmon (Oncorhynchus kisutch) from the Great Lakes

    USGS Publications Warehouse

    Reinert, Robert E.; Bergman, Harold L.

    1974-01-01

    Concentrations of DDT residues were higher in lake trout (Salvelinus namaycush) from southern Lake Michigan in 1966–70 (average 18.1 ppm in fish 558–684 mm long) than in lake trout of the same size-class from Lake Superior in 1968–69 (4.4 ppm), and higher in adult coho salmon (Oncorhynchus kisutch) from Lake Michigan in 1968–71 (averages for different year-classes, 9.9–14.0 ppm) than in those from Lake Erie in 1969 (2.2 ppm). Residues were significantly higher in lake trout from southern Lake Michigan than in those from the northern part of the lake. In lakes Michigan and Superior, the levels increased with length of fish and percentage oil. In Lake Michigan coho salmon, the residues remained nearly stable (2–4 ppm) from September of the 1st yr of lake residence through May or early June of the 2nd yr, but increased three to four times in the next 3 mo. Residues in Lake Erie coho salmon did not increase during this period, which preceded the spawning season. Although the concentrations of total residues in whole, maturing Lake Michigan coho salmon remained unchanged from August 1968 until near the end of the spawning season in January 1969, the residues were redistributed in the tissues of the spawning-run fish; concentrations in the loin and brain were markedly higher in January than in August. This relocation of DDT residues accompanied a marked decrease in the percentage of oil in the fish, from 13.2 in August to 2.8 in January. Concentrations of residues were relatively high in eggs of both lake trout (4.6 ppm) and coho salmon (7.4–10.2 ppm) from Lake Michigan. The percentage composition of the residues (p,p′DDE, o,p′/DDT, p,p′DDT, and p,p′DDT) did not differ significantly with life stage, size, age, or locality, or date of collection of lake trout or coho salmon.

  11. Primary expectations of secondary metabolites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant secondary metabolites (e.g., phenolics) are important for human health, in addition to the organoleptic properties they impart to fresh and processed foods. Consumer expectations such as appearance, taste, or texture influence their purchasing decisions. Thorough identification of phenolic com...

  12. Natural products: Hunting microbial metabolites

    NASA Astrophysics Data System (ADS)

    Schmidt, Eric W.

    2015-05-01

    Symbiotic bacteria synthesize many specialized small molecules; however, establishing the role these chemicals play in human health and disease has been difficult. Now, the chemical structure and mechanism of the Escherichia coli product colibactin provides insight into the link between this secondary metabolite and colorectal cancer.

  13. Automated analysis of oxidative metabolites

    NASA Technical Reports Server (NTRS)

    Furner, R. L. (Inventor)

    1974-01-01

    An automated system for the study of drug metabolism is described. The system monitors the oxidative metabolites of aromatic amines and of compounds which produce formaldehyde on oxidative dealkylation. It includes color developing compositions suitable for detecting hyroxylated aromatic amines and formaldehyde.

  14. METABOLITE PROFILING OF ECHINACEA GENOTYPES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Echinacea extracts have historically been used as herbal remedies to treat colds, coughs and snake bites. Echinacea products are currently sold as a popular herbal-remedy used for general enhancement of the immune system. However, the genetic variation in metabolites has not been systematically ch...

  15. Bisphenol A, Dichlorodiphenyltrichloroethane (DDT) and Vinclozolin Affect ex-vivo Uterine Contraction in Rats via Uterotonin (Prostaglandin F2α, Acetylcholine and Oxytocin) Related Pathways

    PubMed Central

    Salleh, Naguib; Giribabu, Nelli; Feng, Angeline Oh Mei; Myint, Kyaimon

    2015-01-01

    Bisphenol-A (BPA), dichrolodiphenyltrichloroethane (DDT) and vinclozolin were found able to induce abnormal uterine contraction. The mechanisms involved remains unclear. We hypothesized that the effect of these compounds were mediated via the uterotonin pathways. Therefore, in this study, effects of BPA, vinclozolin and DDT-only and in combination with uterotonins (PGF-2α, acetylcholine and oxytocin) on the force and pattern of uterine contraction were observed. Methods: Uteri were harvested from intact adult female rats 24 hours after a single injection (1 mg/kg/b.w) of estrogen to synchronize their oestrous cycle. The uterine horns were subjected for ex-vivo contraction studies in an organ bath connected to Powerlab data acquisition system. Different doses of BPA, vinclozolin and DDT were added into the bathing solution and changes in the pattern and strength of uterine contraction were recorded. Further, increasing doses of uterotonins were concomitantly administered with these compounds and changes in the force and pattern of contraction were observed. Results: In the absence of uterotonins, uterine contractile force decreased with increasing doses of BPA and DDT. However, vinclozolin induced sharp increase in the contractile forces which then gradually decrease. Administration of BPA, DDT and vinclozolin alone reduced the force of uterine contraction following stimulation of contraction by uterotonins. However, BPA, vinclozolin or DDT effects were relieved upon co-administration with uterotonins at increasing doses. Conclusions: The antagonizing effect of uterotonins on BPA, vinclozolin and DDT actions could explain the mechanism underlying the adverse effect of these compounds on uterine contraction. PMID:26640411

  16. o-p′-DDT-mediated uterotrophy and gene expression in immature C57BL/6 mice and Sprague–Dawley rats

    SciTech Connect

    Kwekel, Joshua C.; Forgacs, Agnes L.; Williams, Kurt J.; Zacharewski, Timothy R.

    2013-12-15

    1,1,1-Trichloro-2,2-bis(2-chlorophenyl-4-chlorophenyl)ethane (o,p′-DDT) is an organochlorine pesticide and endocrine disruptor known to activate the estrogen receptor. Comprehensive ligand- and species-comparative dose- and time-dependent studies were conducted to systematically assess the uterine physiological, morphological and gene expression responses elicited by o,p′-DDT and ethynyl estradiol (EE) in immature ovariectomized C57BL/6 mice and Sprague–Dawley rats. Custom cDNA microarrays were used to identify conserved and divergent differential gene expression responses. A total of 1256 genes were differentially expressed by both ligands in both species, 559 of which exhibited similar temporal expression profiles suggesting that o,p′-DDT elicits estrogenic effects at high doses when compared to EE. However, 51 genes exhibited species-specific uterine expression elicited by o,p′-DDT. For example, carbonic anhydrase 2 exhibited species- and ligand-divergent expression as confirmed by quantitative real-time PCR. The identification of comparable temporal phenotypic responses linked to gene expression demonstrates that systematic comparative gene expression assessments are valuable for elucidating conserved and divergent estrogen signaling mechanisms in rodent uterotrophy. - Highlights: • o,p′-DDT and enthynyl estradiol (EE) both elicit uterotrophy in mice and rats. • o,p′-DDT and EE have different kinetics in uterine wet weight induction. • o,p′-DDT elicited stromal hypertrophy in rats but myometrial hypertrophy in mice. • 1256 genes were differentially expressed by both ligands in both species. • Only 51 genes had species-specific uterine expression.

  17. Selective Sweep Analysis in the Genomes of the 91-R and 91-C Drosophila melanogaster Strains Reveals Few of the ‘Usual Suspects’ in Dichlorodiphenyltrichloroethane (DDT) Resistance

    PubMed Central

    Steele, Laura D.; Coates, Brad; Valero, M. Carmen; Sun, Weilin; Seong, Keon Mook; Muir, William M.; Clark, John M.; Pittendrigh, Barry R.

    2015-01-01

    Adaptation of insect phenotypes for survival after exposure to xenobiotics can result from selection at multiple loci with additive genetic effects. To the authors’ knowledge, no selective sweep analysis has been performed to identify such loci in highly dichlorodiphenyltrichloroethane (DDT) resistant insects. Here we compared a highly DDT resistant phenotype in the Drosophila melanogaster (Drosophila) 91-R strain to the DDT susceptible 91-C strain, both of common origin. Whole genome re-sequencing data from pools of individuals was generated separately for 91-R and 91-C, and mapped to the reference Drosophila genome assembly (v. 5.72). Thirteen major and three minor effect chromosome intervals with reduced nucleotide diversity (π) were identified only in the 91-R population. Estimates of Tajima's D (D) showed corresponding evidence of directional selection in these same genome regions of 91-R, however, no similar reductions in π or D estimates were detected in 91-C. An overabundance of non-synonymous proteins coding to synonymous changes were identified in putative open reading frames associated with 91-R. Except for NinaC and Cyp4g1, none of the identified genes were the ‘usual suspects’ previously observed to be associated with DDT resistance. Additionally, up-regulated ATP-binding cassette transporters have been previously associated with DDT resistance; however, here we identified a structurally altered MDR49 candidate resistance gene. The remaining fourteen genes have not previously been shown to be associated with DDT resistance. These results suggest hitherto unknown mechanisms of DDT resistance, most of which have been overlooked in previous transcriptional studies, with some genes having orthologs in mammals. PMID:25826265

  18. Effects of different treatments on soil-borne DDT and HCH dynamics and plant uptake.

    PubMed

    Li, Huashou; Ling, Weifeng; Lin, Chuxia

    2011-01-01

    Pot experiments were conducted to examine the effects of various fertilizers, as well as soil dilution treatments on the dynamics of soil-borne DDTs [sum of dichlorodiphenyltrichloroethane (DDT), chlorodiphenyldichloroethylene (DDE) and di- chlorodiphenyldichloroethane (DDD)] and hexachlorocyclohexanes (HCHs, sum of α-HCH, β-HCH, γ-HCH and δ-HCH) and their subsequent impacts on the uptake of DDTs and HCHs by a test plant. The results show that the soil residual DDTs and HCHs concentrations in the iron-rich fertilizer-treated soil were significantly lower than those in other fertilizer-treated soils. There was a close relationship between the soil residual DDTs and the plant tissue DDTs. This suggests that the uptake rate of DDTs by the plant was dependent on the concentration of soil-borne DDTs. A less close relationship between soil residual HCHs and plant tissue HCHs was also observed. Dilution of pesticide-contaminated soil with the non-contaminated soil not only physically reduced the concentration of pesticides in the soil but also enhanced the loss of soil-borne pesticides, possibly through the improvement of soil conditions for microbial degradation. Soil dilution had a better effect on promoting the loss of soil-borne HCHs, relative to soil-borne-DDTs. The research findings obtained from this study have implications for management of heavily contaminated soils with DDTs and HCHs. Remediation of DDTs and HCHs-contaminated soils in a cost-effective way can be achieved by incorporating treatment techniques into conventional agricultural practices. Applications of iron-rich fertilizer and soil dilution treatments could cost-effectively reduce soil-borne DDTs and HCHs, and subsequently the uptake of these organochlorine pesticides by vegetables. PMID:21790304

  19. Identification of Epoxide-Derived Metabolite(s) of Benzbromarone.

    PubMed

    Wang, Kai; Wang, Hui; Peng, Ying; Zheng, Jiang

    2016-04-01

    Benzbromarone (BBR) is a benzofuran derivative that has been quite useful for the treatment of gout; however, it was withdrawn from European markets in 2003 because of reported serious incidents of drug-induced liver injury. BBR-induced hepatotoxicity has been suggested to be associated with the formation of a quinone intermediate. The present study reported epoxide-derived intermediate(s) of BBR. An N-acetylcysteine (NAC) conjugate derived from epoxide metabolite(s) was detected in both microsomal incubations of BBR and urine samples of mice treated with BBR. The NAC conjugate was identified as 6-NAC BBR. Ketoconazole suppressed the bioactivation of BBR to the epoxide intermediate(s), and the CYP3A subfamily was the primary enzyme responsible for the formation of the epoxide(s). The present study provided new information on metabolic activation of BBR. PMID:26792818

  20. Global Perspectives of Fungal Secondary Metabolite Research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungi produce a wide range of unusual metabolites, termed secondary metabolites because they play no role in the normal, basic metabolic pathways used for growth and energy production, etc. Some of these secondary metabolites have antibiotic properties; others are potent toxins that are dangerous w...

  1. Using multi-walled carbon nanotubes as solid phase extraction adsorbents to determine dichlorodiphenyltrichloroethane and its metabolites at trace level in water samples by high performance liquid chromatography with UV detection.

    PubMed

    Zhou, Qingxiang; Xiao, Junping; Wang, Weidong

    2006-09-01

    Carbon nanotubes (CNTs) are a kind of new carbon-based nano-materials which have drawn great attention in many application fields. The potential of multi-walled carbon nanotubes (MWNTs) as solid-phase extraction (SPE) adsorbents for the preconcentration of environmental pollutants has been investigated in recent years. The goal of this work was to investigate the feasibility of MWNTs used as SPE adsorbents to enrich dichlorodiphenyltrichloroethane (DDT) and its metabolites including 1,1-dichloro-2,2-bis-(4'-chlorophenyl)ethane (DDD) and 1,1-dichloro-2,2-bis-(4'-chlorophenyl)ethane (DDE) at trace level which are typical persistent organic pollutants in environment. Parameters that maybe influence the extraction efficiency such as the eluent volume, sample flow rate, sample pH and the sample volume were optimized in detail. The experimental results showed the excellent linear relationship between peak area and the concentration of DDT and its metabolites over the range of 0.2-60 microg L(-1), and the precisions (RSD) were 2.3-2.5% under the optimal conditions. The detection limits of proposed method could reach 4-13 ng L(-1) based on the ratio of chromatographic signal to base line noise (S/N = 3). Satisfied results were achieved when the proposed method was applied to determine the four target compounds in realworld water samples with spiked recoveries over the range of 89.7-115.5%. All these facts indicated that MWCNTs as SPE packing materials coupled to HPLC was an excellent alternative for the routine analysis of DDT and its metabolites at trace level in environment. PMID:16797570

  2. Antileishmanial Metabolites from Geosmithia langdonii

    PubMed Central

    2015-01-01

    Antileishmanial bioassay guided fractionation of Geosmithia langdonii has resulted in the isolation and identification of two new compounds (1 and 2) together with 10 known compounds (3–12). The structures of the isolated metabolites were elucidated based on comprehensive 1D and 2D NMR spectroscopic data as well as mass spectrometry. The absolute configuration at C4, C5, and C6 of 2 was determined as R using a modified Mosher esterification method and NOESY correlations. The extracts and the isolated metabolites were evaluated for their antileishmanial activities. Compounds 3, 9, 11, and 12 were found to be active against Leishmania donovani with IC50 values of 6.9, 3.3, 8.5, and 9.2 μM, respectively, while compounds 1, 5, and 10 showed lower activities against L. donovani with IC50 values of 13.0, 47.3, and 34.0 μM, respectively. PMID:25084548

  3. Tissue distribution of HCH and DDT congeners and human health risk associated with consumption of fish collected from Kabul River, Pakistan.

    PubMed

    Aamir, Muhammad; Khan, Sardar; Nawab, Javed; Qamar, Zahir; Khan, Anwarzeb

    2016-03-01

    Distribution of hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) congeners in tissues of four different fish species and their associated potential health risks to local consumers are presented in this paper. The average ∑(HCHs+DDTs) concentration in Glyptothorax punjabensis (214ngg(-1) wet weight (ww)) (carnivores) was found higher than Tor putitora (155ngg(-1) ww) (herbivores). The distribution of ∑(HCHs+DDTs) in all fish tissues was found in order of liver>muscle>stomach>gills. The profile of congeners (β-HCH/∑HCH from 0.29-0.47) indicated that all selected fish species were contaminated with HCH because of its recent usage in the study area. Furthermore, DDT profile ((DDE+DDD)/∑DDT from 0.61-0.78) showed that fish contamination with DDT originated from past usage and long-time degradation mechanism. The average estimated daily dietary intake of ∑HCHs (15.0ngkg(-1) day(-1)) was higher than ∑DDTs (12.5ngkg(-1) day(-1)) by the local consumers via fish consumption. On the basis of both 50th and 95th percentile exposure levels, the carcinogenic hazard ratios for DDT and its congeners were exceeded one (safe limit) for all fish species, indicating a great potential cancer risk for local consumers with life time consumption of contaminated fish collected from Kabul River. PMID:26685785

  4. QSAR analyses of DDT analogues and their in silico validation using molecular docking study against voltage-gated sodium channel of Anopheles funestus.

    PubMed

    Saini, V; Kumar, A

    2014-01-01

    DDT has enjoyed the reputation of a successful pesticide in disease control programme and agricultural practices along with the serious opposition and ban later on due to its biomagnification and toxic action against non-target organisms. The present work was carried out to develop QSAR models for analysing DDT analogues for their pesticidal activity and in silico validation of these models. A 2D-QSAR model was generated using stepwise with multiple regression, and the model with a value of r(2) = 0.7324; q(2) = 0.6215; pred r(2) = 0.7038, containing five descriptors, was selected for further study. The 3D QSAR with CoMFA analysis showed that steric contribution of 21% and electrostatic contribution of about 79% were required for larvicidal activity of DDT analogues. A set of 3430 molecules was generated using the basic DDT skeleton as template, and these were evaluated for their mosquito larvicidal activity using the generated QSAR models and DDT as standard. Eleven molecules were selected for in silico validation of these models. For this, a docking study of the selected molecules against the homology-modelled voltage-gated sodium channel of Anopheles funestus was conducted. The study showed that the activities of these analogues as predicted by 2D-QSAR, 3D-QSAR with CoMFA and dock score were observed to be well correlated. PMID:25271473

  5. DDT degradation efficiency and ecotoxicological effects of two types of nano-sized zero-valent iron (nZVI) in water and soil.

    PubMed

    El-Temsah, Yehia S; Sevcu, Alena; Bobcikova, Katerina; Cernik, Miroslav; Joner, Erik J

    2016-02-01

    Nano-scale zero-valent iron (nZVI) has been conceived for cost-efficient degradation of chlorinated pollutants in soil as an alternative to e.g permeable reactive barriers or excavation. Little is however known about its efficiency in degradation of the ubiquitous environmental pollutant DDT and its secondary effects on organisms. Here, two types of nZVI (type B made using precipitation with borohydride, and type T produced by gas phase reduction of iron oxides under H2) were compared for efficiency in degradation of DDT in water and in a historically (>45 years) contaminated soil (24 mg kg(-1) DDT). Further, the ecotoxicity of soil and water was tested on plants (barley and flax), earthworms (Eisenia fetida), ostracods (Heterocypris incongruens), and bacteria (Escherichia coli). Both types of nZVI effectively degraded DDT in water, but showed lower degradation of aged DDT in soil. Both types of nZVI had negative impact on the tested organisms, with nZVI-T giving least adverse effects. Negative effects were mostly due to oxidation of nZVI, resulting in O2 consumption and excess Fe(II) in water and soil. PMID:26598990

  6. Theoretical study on the OH-initiated atmospheric reaction of 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT)

    NASA Astrophysics Data System (ADS)

    Bai, Jing; Yang, Wenbo; Zhang, Chenxi; Zhao, Yuyang; Gong, Chen; Sun, Xiaomin; Zhang, Qingzhu; Wang, Wenxing

    2013-03-01

    p,p'-DDT is a member of the widely used organochlorine pesticides. In this paper, the mechanism for the OH-initiated reaction of p,p'-DDT is studied at the MPWB1K/6-311 + G(3df,2p)//MPWB1K/6-31 + G(d,p) level. The OH addition reaction to the C2 atom and H abstraction reaction from alkyl are energetically favorable pathways in OH-initiated reactions of DDT. On the basis of the quantum chemical information, the Rice-Ramsperger-Kassel-Marcus (RRKM) theory is used to calculate the rate constants over the temperature range of 200-800 K. The OH addition reaction is dominant according to the branching ratio, and the atmospheric lifetime of p,p'-DDT is 7.9 days. This work provides a comprehensive understanding of the OH-initiated atmospheric degradation of p,p'-DDT which is helpful for experiments and risk assessment.

  7. Post World War II orcharding creates present day DDT-problems in The Sørfjord (Western Norway)--a case study.

    PubMed

    Ruus, Anders; Green, Norman W; Maage, Amund; Amundsen, Carl Einar; Schøyen, Merete; Skei, Jens

    2010-10-01

    The Sørfjord has a long history of agriculture and industry, and environmental monitoring has been conducted for decades, comprising analyses of contaminants in mussel, fish and sediments. DDT was used as an insecticide in orchards surrounding the fjord between World War II and 1970. Since the early 1990 s, elevated concentrations of DDT were found in mussels and fish. Unexpectedly, DDT-concentrations increased towards present day, despite the discontinuation of use. The highest concentrations in mussels (in 2006) corresponded to about two orders of magnitude higher than background. Analyses of sediment core sections also indicated increased input towards present day. Shifts in climatic parameters, as well as increased amounts of soil dissolved organic carbon following a decline in atmospheric sulphate deposition may have contributed to this phenomenon. We warrant the need for increased knowledge of the effects of alterations in variables acting regionally and globally on the disposition of contaminants in ecosystems. PMID:20719343

  8. Global environmental cycling of gamma-HCH and DDT in the 1980s--a study using a coupled atmosphere and ocean general circulation model.

    PubMed

    Guglielmo, Francesca; Lammel, Gerhard; Maier-Reimer, Ernst

    2009-09-01

    A coupled atmosphere-ocean general circulation model, ECHAM5-MPIOM, was used to study the multicompartmental cycling and long-range transport of persistent and semivolatile organics. Multiphase systems in air and ocean are covered by submodels for atmospheric aerosols, HAM, and marine biogeochemistry, HAMOCC5, respectively. The model, furthermore, encompasses 2D surface compartments, i.e. top soil, vegetation surfaces and sea-ice. The total environmental fate of gamma-hexachlorocyclohexane (gamma-HCH, lindane) and dichlorophenyltrichloroethane (DDT) in agriculture were studied. DDT is mostly present in the soils, the water-soluble gamma-HCH in soils and ocean. DDT has the longest residence time in almost all compartments. Quasi-steady state with regard to substance accumulation is reached within a few years in air and vegetation surfaces. In seawater the partitioning to suspended and sinking particles contributes to the vertical transport of substances. On the global scale deep water formation is, however, found to be more efficient. Up to 30% of DDT but only less than 0.2% of gamma-HCH in seawater are stored in particulate matter. On the time scale studied (1 decade) and on global scale substance transport in the environment is determined by the fast atmospheric circulation. The meridional transport mechanism, for both compounds, is significantly enhanced by multi-hopping. Net meridional transport in the ocean is effective only regionally, mostly by currents along the western boundaries of Africa and the Americas. The total environmental burdens of the substances experience a net northward migration from their source regions, which is more pronounced for DDT than for gamma-HCH. Due to the application distribution, however, after 10 years of simulation 21% of the global environmental burden of gamma-HCH and 12% of DDT have accumulated in the Arctic. PMID:19576616

  9. [Xenopsylla cheopis (Siphonaptera: Xenopsyllinae), fleas in rural plague areas of high altitude Madagascar: level of sensitivity to DDT, pyrethroids and carbamates after 50 years of chemical vector control].

    PubMed

    Ratovonjato, J; Duchemin, J B; Duplantier, J M; Chanteau, S

    2000-01-01

    The resistance of Xenopsylla cheopis from urban area to pyrethroids, to DDT, and their susceptibility to carbamate are known. We have evaluated the susceptibility of X. cheopis collected from three rural localities: Ambodisiarivo (district of Antananarivo Avaradrano), Mandoto (district of Betafo), Analaroa (district of Anjozorobe) in the province of Antananarivo and in Besoa (district of Ambalavao) in the province of Fianarantsoa. The standard WHO protocol was used and four insecticides were tested: deltamethrin 0.025%, cyfluthrin 0.15% (pyrethroids), DDT 4% (organochlorine), propoxur 1% and bendiocarb 0.1% (carbamate). X. cheopis has been shown resistance to DDT 4%, to deltamethrin 0.025% but was susceptible in the rural area around Antananarivo City. They were tolerant to deltamethrin 0.025% and cyfluthrin 0.15% but susceptible to propoxur 0.1% and bendiocarbe 1% in the districts of Betafo and Anjozorobe. In Besoa, X. cheopis was resistant to DDT 4%, tolerant to deltamethrin 0.025% and cyfluthrin 0.15% but susceptible to propoxur 0.1% and bendiocarbe 1%. These results indicate that DDT and pyrethroids can not be recommended any more for the vector control in the rural area around the capital. The use of pyrethroids in the other districts of the central highland must be joined with a X. cheopis susceptibility control. In case of resistance to pyrethroids, carbamates would be proposed to control plague vector in the rural area. The high level of resistance to DDT and pyrethroid in the rural area around the capital confirms the importance of studying the flea population in different area of Madagascar and the possibility of the gene resistance propagation. PMID:12463026

  10. Computer Simulations to Study the Effects of Explosive and Confinement Properties on the Deflagration to Detonation Transition (DDT)

    NASA Astrophysics Data System (ADS)

    Reaugh, John; Curtis, John; Maheswaran, Mary-Ann

    2013-06-01

    We have augmented the HERMES model (High Explosive Response to MEchanical Stimulus) by adding a modification to the CREST (Computational Reaction Evolution dependent on Entropy (S) and Time) detonation model. We have applied the combined model in ALE 3D to simulate DDT in an experimental configuration comprising an explosive confined in a tube and ignited at one end. We assess the quantitative effects of explosive properties and of tube geometry and material properties on the location of the detonation transition. For a fixed porosity, we find that the specific surface area of the explosive particles, in combination with the explosive's pressure-dependent burn rate, have strong influence on the transition to detonation. The run-to-detonation properties of the explosive powder (given by the Pop-plot) also have strong effect. In our simulations, the speed of the ignition front has less effect on the transition. The ignition front is caused by hot product gas moving through the permeable bed of explosive particles. In our single-velocity, multi-species approximation, we specify the ignition front speed as an input parameter. The results of our simulations help us identify the independent experiments that must be performed and analysed before a model for DDT can be validated. JER's activity was performed under the auspices of the US DOE by LLNL under Contract DE-AC52-07NA27344, and partially funded by the Joint US DoD/DOE Munitions Technology Development Program.

  11. Dose-response studies on promoting and anticarcinogenic effects of phenobarbital and DDT in the rat hepatocarcinogenesis.

    PubMed

    Kitagawa, T; Hino, O; Nomura, K; Sugano, H

    1984-12-01

    Possible discrepancy between the dose level required for promoting action, when given after initiation process, and that needed to exert an anticarcinogenic effect when given simultaneously with a carcinogen, of hepatic promoters were investigated in an attempt to obtain a 'practical' threshold dose of promoters. Phenobarbital (PB) and dichlorophenyltrichloroethane (DDT) were used as promoters and 3'-methyl-4-(dimethylamino)-azobenzene (3'-Me-DAB) was used as the carcinogen. Male weanling rats were treated with 600 p.p.m. 3'-Me-DAB for 3 weeks followed by a diet containing a promoter at various dose levels (5-500 p.p.m.), or the animals were treated with a low dose (100 p.p.m.) of 3'-Me-DAB plus a promoter at various dose levels (20-500 p.p.m.). The effects of promoters were measured by scoring size and number of enzyme-altered islands at weeks 12 and 24 of rat age. The promoting effect of PB and DDT was demonstrated in dose-dependent fashion, in the dose range of 10-500 p.p.m. and 20-500 p.p.m., respectively. On the other hand, promoters given simultaneously with a low dose of carcinogen enhanced the carcinogenesis at all the dose levels tested, quite in contrast with their inhibitory effect on carcinogenesis when given together with relatively high doses of carcinogens. PMID:6499117

  12. Additional Selection for Insecticide Resistance in Urban Malaria Vectors: DDT Resistance in Anopheles arabiensis from Bobo-Dioulasso, Burkina Faso

    PubMed Central

    Jones, Christopher M.; Toé, Hyacinthe K.; Sanou, Antoine; Namountougou, Moussa; Hughes, Angela; Diabaté, Abdoulaye; Dabiré, Roch; Simard, Frederic; Ranson, Hilary

    2012-01-01

    In the city of Bobo-Dioulasso in Burkina Faso, Anopheles arabiensis has superseded Anopheles gambiae s.s. as the major malaria vector and the larvae are found in highly polluted habitats normally considered unsuitable for Anopheles mosquitoes. Here we show that An. gambiae s.l. adults emerging from a highly polluted site in the city centre (Dioulassoba) have a high prevalence of DDT resistance (percentage mortality after exposure to diagnostic dose = 65.8% in the dry season and 70.4% in the rainy season, respectively). An investigation into the mechanisms responsible found an unexpectedly high frequency of the 1014S kdr mutation (allele frequency = 0.4), which is found at very low frequencies in An. arabiensis in the surrounding rural areas, and an increase in transcript levels of several detoxification genes, notably from the glutathione transferase and cytochrome P450 gene families. A number of ABC transporter genes were also expressed at elevated levels in the DDT resistant An. arabiensis. Unplanned urbanisation provides numerous breeding grounds for mosquitoes. The finding that Anopheles mosquitoes adapted to these urban breeding sites have a high prevalence of insecticide resistance has important implications for our understanding of the selective forces responsible for the rapid spread of insecticide resistant populations of malaria vectors in Africa. PMID:23049917

  13. The long shadow of our chemical past - High DDT concentrations in fish near a former agrochemicals factory in England.

    PubMed

    Jürgens, Monika D; Crosse, John; Hamilton, Patrick B; Johnson, Andrew C; Jones, Kevin C

    2016-11-01

    A total of 81 roach (Rutilus rutilus) collected from 13 southern English river sites between 2007 and 2012, were analysed for organochlorine pesticides, PCBs, PBDEs and some metals. Unexpectedly high concentrations of the banned insecticide DDT and its degradation products DDE and DDD (∑DDTs) were found in the 10 fish from the river Lee (or Lea) which averaged 88 ± 70 (standard deviation) μg/kg ww, almost 20 times higher than the average for the remaining sites (4.8 ± 3.1 μg/kg). All fish from that site exceeded the Canadian Tissue Residue Guideline (environmental quality standard) of 14 μg/kg ∑DDTs. Concentrations of the insecticides chlordane and lindane as well as copper, which is often used as a fungicide, were also elevated in fish from the Lee, though not as much as those of DDTs. A likely explanation for these observations was found in a nearby former pesticide factory, which had stopped production about three decades earlier. An extensive review of recent literature data on DDT in wild European fish found that, while levels are now generally low, there were several other hotspots with ∑DDTs levels that may still be of concern. PMID:27518925

  14. Effect of feeding and of DDT on the activity of hepatic glucose 6- phosphate dehydrogenase in two salmonids

    USGS Publications Warehouse

    Buhler, Donald R.; Benville, P.

    1969-01-01

    The specific activity of liver glucose 6-phosphate dehydrogenase in yearling rainbow trout remained unchanged when the fish were starved for periods as long as 8 weeks and when starved animals were fed diets of various compositions. Injection of insulin concurrently with refeeding also failed to alter the specific activity of the enzyme in trout. The absence of a dietary or insulin influence on the teleost enzyme system is to be contrasted with studies in mammals in which the activity of hepatic glucose 6-P dehydrogenase was markedly stimulated after refeeding starved animals or injection of insulin.Ingestion of the pesticide DDT by juvenile coho salmon or adult rainbow trout also had no effect on the specific activity of liver glucose 6-P dehydrogenase and DDT failed to inhibit the rainbow trout enzyme in vitro. These results also differ considerably from those found in higher animals.These results suggest that the glucose 6-P dehydrogenase enzyme in teleosts may be under a different type of regulatory control from that found in mammals.

  15. The effect of larval nutritional deprivation on the life history and DDT resistance phenotype in laboratory strains of the malaria vector Anopheles arabiensis

    PubMed Central

    2013-01-01

    Background Anopheles arabiensis is a major malaria vector in Africa. It thrives in agricultural areas and has been associated with increased malaria incidence in areas under rice and maize cultivation. This effect may be due to increased adult size and abundance as a consequence of optimal larval nutrition. The aim of this study was to examine the effect of larval nutrition on the life history and expression of insecticide resistance in adults of laboratory reared An. arabiensis. Methods Larvae drawn from an insecticide susceptible An. arabiensis strain (SENN) as well as a DDT-resistant strain (SENN-DDT) were subjected to three fasting regimes: 1 mg of food per larva offered once per day, once every second day and once every third day. Control cohorts included larvae offered 1 mg food thrice per day. The rate of larval development was compared between matched cohorts from each strain as well as between fasted larvae and their respective controls. The expression of DDT resistance/tolerance in adults was compared between the starved cohorts and their controls by strain. Factors potentially affecting variation in DDT resistance/tolerance were examined including: adult body size (wing length), knock-down resistance (kdr) status and levels of detoxification enzyme activity. Results and conclusion Anopheles arabiensis larval development is prolonged by nutrient deprivation and adults that eclose from starved larvae are smaller and less tolerant to DDT intoxication. This effect on DDT tolerance in adults is also associated with reduced detoxification enzyme activity. Conversely, well fed larvae develop comparatively quickly into large, more DDT tolerant (SENN) or resistant (SENN-DDT) adults. This is important in those instances where cereal farming is associated with increased An. arabiensis transmitted malaria incidence, because large adult females with high teneral reserves and decreased susceptibility to insecticide intoxication may also prove to be more

  16. Formed and preformed metabolites: facts and comparisons.

    PubMed

    Pang, K Sandy; Morris, Marilyn E; Sun, Huadong

    2008-10-01

    The administration of metabolites arising from new drug entities is often employed in drug discovery to investigate their associated toxicity. It is expected that administration of metabolites can predict the exposure of metabolites originating from the administration of precursor drug. Whether exact and meaningful information can be obtained from this has been a topic of debate. This communication summarizes observations and theoretical relationships based on physiological modelling for the liver, kidney and intestine, three major eliminating organs/tissues. Theoretical solutions based on physiological modelling of organs were solved, and the results suggest that deviations are expected. Here, examples of metabolite kinetics observed mostly in perfused organs that did not match predictions are provided. For the liver, discrepancies in fate between formed and preformed metabolites may be explained by the heterogeneity of enzymes, the presence of membrane barriers and whether transporters are involved. For the kidney, differences have been attributed to glomerular filtration of the preformed but not the formed metabolite. For the intestine, the complexity of segregated flows to the enterocyte and serosal layers and differences in metabolism due to the route of administration are addressed. Administration of the metabolite may or may not directly reflect the toxicity associated with drug use. However, kinetic data on the preformed metabolite will be extremely useful to develop a sound model for modelling and simulations; in-vitro evidence on metabolite handling at the target organ is also paramount. Subsequent modelling and simulation of metabolite data arising from a combined model based on both drug and preformed metabolite data are needed to improve predictions on the behaviours of formed metabolites. PMID:18812018

  17. Aspirin metabolites are GPR35 agonists.

    PubMed

    Deng, Huayun; Fang, Ye

    2012-07-01

    Aspirin is widely used as an anti-inflammatory, anti-platelet, anti-pyretic, and cancer-preventive agent; however, the molecular mode of action is unlikely due entirely to the inhibition of cyclooxygenases. Here, we report the agonist activity of several aspirin metabolites at GPR35, a poorly characterized orphan G protein-coupled receptor. 2,3,5-Trihydroxybenzoic acid, an aspirin catabolite, was found to be the most potent GPR35 agonist among aspirin metabolites. Salicyluric acid, the main metabolite of aspirin, was also active. These results suggest that the GPR35 agonist activity of certain aspirin metabolites may contribute to the clinical features of aspirin. PMID:22526472

  18. Genome-wide sequencing and an open reading frame analysis of dichlorodiphenyltrichloroethane (DDT) susceptible (91-C) and resistant (91-R) Drosophila melanogaster laboratory populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Drosophila melanogaster 91-R and 91-C strains are of common origin, however, 91-R has been intensely selected for dichlorodiphenyltrichloroethane (DDT) resistance over six decades while 91-C has been maintained as the non-selected control strain. These fly strains represent a unique genetic res...

  19. Selective sweep analysis in the genomes of the 91-R and 91-C Drosophila melanogaster strains reveals few of the ‘usual suspects’ in Dichlorodiphenyltrichloroethane (DDT) resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adaptation of insect phenotypes for survival after exposure to xenobiotics can result from selection at multiple loci with additive genetic effects. A high level dichlorodiphenyltrichloroethane (DDT) resistance phenotype in the Drosophila melanogaster strain 91-R has resulted due to continuous labo...

  20. Effect of DDT and MCPA (4-chloro-2-methylphenoxyacetic acid) on reproduction of the pond snail, Lymnaea stagnalis L

    SciTech Connect

    Woin, P.; Broenmark, C. )

    1992-01-01

    Reproduction is the single most important function in the life cycle of an organism. Successful reproduction determines fitness of organisms. The inability of an organism to complete any one stage of the reproductive process severely reduces its lifetime reproductive success. Disruptions in the reproduction will ultimately affect the abundance and distribution of the species. Therefore, laboratory tests of long-term impact of sublethal pollutant concentrations on organisms preferably is done on the reproductive success. Pollutants of diverse structure may affect the reproductive system which is sensitive to toxic agents. Certain pollutants, notably the organochlorine compounds, have been shown to affect the male and female reproductive systems. The authors have studied the effect of sublethal concentrations of DDT and the herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA) on the reproductive output of the pulmonate snail Lymnaea stagnalis under a 2-mon exposure period.

  1. Chlordane, DDT, PCB's, and other selected organic compounds in Asiatic clams and yellow bullhead in the Potomac River Basin, 1992

    USGS Publications Warehouse

    Zappia, Humbert

    1996-01-01

    Chlordane, DDT (dichlor-diphenyl-trichloroethane), and PCB's (polychlorinated biphenyls) were the most widespread organic contaminants detected during a 1992 survey of aquatic biological tissues in the Potomac River Basin. On the basis of existing U.S. Food and Drug Administration criteria, no new threats to human health were discovered, although chlordane concentrations may pose a threat to fish-eating wildlife. Chlordane exceeded the National Academy of Science and National Academy of Engineering recommended maximum concentration for the protection of fish-eating wildlife at two sites. The survey, conducted by the U.S. Geological Survey's National Water-Quality Assessment Program, sampled Asiatic clams (Corbicula fluminea) and yellow bullhead (Ameiurus natalis) at 16 sites to determine the occurrence and distribution of 29 hydrophobic organic compounds. Thirteen of these organic compounds were detected in the survey. Sites with the greatest number of compounds detected include the Potomac River near Alexandria, Va., with 6 compounds detected in Asiatic clam tissue, and Accotink Creek near Annandale, Va., with 11 compounds in yellow bullhead tissue. Chlordane was detected at six sites, with maximum concentrations of 31.1 ?g/kg (micrograms per kilograms) in Asiatic clam tissue and 127 ?g/kg in yellow bullhead whole-fish tissue. DDT was detected at five sites, with maximum concentrations of 12.9 ?g/kg in Asiatic clam tissue and 7.6 ?g/kg in yellow bullhead whole-fish tissue. PCB's were detected at nine sites, with maximum concentrations of 162 ?g/kg in Asiatic clam tissue and 146 mg/ kg in yellow bullhead whole-fish tissue.

  2. Complicating factors in safety testing of drug metabolites: Kinetic differences between generated and preformed metabolites

    SciTech Connect

    Prueksaritanont, Thomayant . E-mail: thomayant_prueksaritanont@merck.com; Lin, Jiunn H.; Baillie, Thomas A.

    2006-12-01

    This paper aims to provide a scientifically based perspective on issues surrounding the proposed toxicology testing of synthetic drug metabolites as a means of ensuring adequate nonclinical safety evaluation of drug candidates that generate metabolites considered either to be unique to humans or are present at much higher levels in humans than in preclinical species. We put forward a number of theoretical considerations and present several specific examples where the kinetic behavior of a preformed metabolite given to animals or humans differs from that of the corresponding metabolite generated endogenously from its parent. The potential ramifications of this phenomenon are that the results of toxicity testing of the preformed metabolite may be misleading and fail to characterize the true toxicological contribution of the metabolite when formed from the parent. It is anticipated that such complications would be evident in situations where (a) differences exist in the accumulation of the preformed versus generated metabolites in specific tissues, and (b) the metabolite undergoes sequential metabolism to a downstream product that is toxic, leading to differences in tissue-specific toxicity. Owing to the complex nature of this subject, there is a need to treat drug metabolite issues in safety assessment on a case-by-case basis, in which a knowledge of metabolite kinetics is employed to validate experimental paradigms that entail administration of preformed metabolites to animal models.

  3. A New Paradigm for Known Metabolite Identification in Metabonomics/Metabolomics: Metabolite Identification Efficiency

    PubMed Central

    Everett, Jeremy R.

    2015-01-01

    A new paradigm is proposed for assessing confidence in the identification of known metabolites in metabonomics studies using NMR spectroscopy approaches. This new paradigm is based upon the analysis of the amount of metabolite identification information retrieved from NMR spectra relative to the molecular size of the metabolite. Several new indices are proposed including: metabolite identification efficiency (MIE) and metabolite identification carbon efficiency (MICE), both of which can be easily calculated. These indices, together with some guidelines, can be used to provide a better indication of known metabolite identification confidence in metabonomics studies than existing methods. Since known metabolite identification in untargeted metabonomics studies is one of the key bottlenecks facing the science currently, it is hoped that these concepts based on molecular spectroscopic informatics, will find utility in the field. PMID:25750701

  4. Protective Efficacy of Vitamins C and E on p,p′-DDT-Induced Cytotoxicity via the ROS-Mediated Mitochondrial Pathway and NF-κB/FasL Pathway

    PubMed Central

    Jin, Xiaoting; Song, Li; Liu, Xiangyuan; Chen, Meilan; Li, Zhuoyu; Cheng, Long; Ren, Hua

    2014-01-01

    Dichlorodiphenoxytrichloroethane (DDT) is a known persistent organic pollutant and liver damage toxicant. However, there has been little emphasis on the mechanism underlying liver damage toxicity of DDT and the relevant effective inhibitors. Hence, the present study was conducted to explore the protective effects of vitamin C (VC) and vitamin E (VE) on the cytotoxicity of DDT in HL-7702 cells and elaborate the specific molecular mechanisms. The results demonstrated that p,p′-DDT exposure at over 10 µM depleted cell viability of HL-7702 cells and led to cell apoptotic. p,p′-DDT treatment elevated the level of reactive oxygen species (ROS) generation, induced mitochondrial membrane potential, and released cytochrome c into the cytosol, with subsequent elevations of Bax and p53, along with suppression of Bcl-2. In addition, the activations of caspase-3 and -8 were triggered. Furthermore, p,p′-DDT promoted the expressions of NF-κB and FasL. When the cells were exposed to the NF-κB inhibitor (PDTC), the up-regulated expression of FasL was attenuated. Strikingly, these alterations caused by DDT treatment were prevented or reversed by the addition of VC or VE, and the protective effects of co-treatment with VC and VE were higher than the single supplement with p,p′-DDT. Taken together, these findings provide novel experimental evidences supporting that VC or/and VE could reduce p,p′-DDT-induced cytotoxicity of HL-7702 cells via the ROS-mediated mitochondrial pathway and NF-κB/FasL pathway. PMID:25464339

  5. Urinary metabolites of diisodecyl phthalate in rats.

    PubMed

    Kato, Kayoko; Silva, Manori J; Wolf, Cynthia; Gray, L Earl; Needham, Larry L; Calafat, Antonia M

    2007-07-01

    Diisodecyl phthalate (DiDP) is an isomeric mixture of phthalates with predominantly 10-carbon branched-dialkyl chains, widely used as a plasticizer for polyvinyl chloride. The extent of human exposure to DiDP is unknown in part because adequate biomarkers of exposure to DiDP are not available. We identified several major metabolites of DiDP in urine of adult female Sprague-Dawley rats after a single oral administration of DiDP (300 mg/kg). These metabolites can potentially be used as biomarkers of exposure to DiDP. The metabolites extracted from urine were chromatographically resolved and identified by their chromatographic behavior and full scan negative ion electrospray ionization mass spectrum. The identity of metabolites with similar molecular weights was further examined in accurate mass mode. For some metabolites, unequivocal identification was done using authentic standards. Among these were the hydrolytic monoester of DiDP, monoisodecyl phthalate (MiDP), detected as a minor metabolite, and one omega oxidation product of MiDP, mono(carboxy-isononyl) phthalate (MCiNP), which was the most abundant urinary metabolite. We also tentatively identified other secondary metabolites of MiDP, mono(hydroxy-isodecyl) phthalate, mono(oxo-isodecyl) phthalate, mono(carboxy-isoheptyl) phthalate, mono(carboxy-isohexyl) phthalate, mono(carboxy-isopentyl) phthalate, mono(carboxy-isobutyl) phthalate, and mono(carboxy-ethyl) phthalate. Oxidative metabolites of diisoundecyl phthalate (DiUdP) and diisononyl phthalate (DiNP) were also detected suggesting the presence of DiUdP and DiNP in the DiDP formulation. The urinary concentrations of all these metabolites gradually decreased in the 4 days following the administration of DiDP. MCiNP and other DiDP secondary metabolites are more abundant in urine than MiDP, suggesting that these oxidative products are better biomarkers for DiDP exposure assessment than MiDP. Additional research on the toxicokinetics of these metabolites is needed

  6. 40 CFR 159.179 - Metabolites, degradates, contaminants, and impurities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... chemical properties of the metabolite or degradate. (B) Data regarding structurally analogous chemicals. (C) Data regarding chemical reactivity of the metabolite or degradate and structurally analogous...

  7. 40 CFR 159.179 - Metabolites, degradates, contaminants, and impurities.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... chemical properties of the metabolite or degradate. (B) Data regarding structurally analogous chemicals. (C) Data regarding chemical reactivity of the metabolite or degradate and structurally analogous...

  8. 40 CFR 159.179 - Metabolites, degradates, contaminants, and impurities.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... chemical properties of the metabolite or degradate. (B) Data regarding structurally analogous chemicals. (C) Data regarding chemical reactivity of the metabolite or degradate and structurally analogous...

  9. Application of mass spectrometry for metabolite identification.

    PubMed

    Ma, Shuguang; Chowdhury, Swapan K; Alton, Kevin B

    2006-06-01

    Metabolism studies play a pivotal role in drug discovery and development. Characterization of metabolic "hot-spots" as well as reactive and pharmacologically active metabolites is critical to designing new drug candidates with improved metabolic stability, toxicological profile and efficacy. Metabolite identification in the preclinical species used for safety evaluation is required in order to determine whether human metabolites have been adequately tested during non-clinical safety assessment. From an instrumental standpoint, high performance liquid chromatography (HPLC) coupled with mass spectrometry (MS) dominates all analytical tools used for metabolite identification. The general strategies employed for metabolite identification in both drug discovery and drug development settings together with sample preparation techniques are reviewed herein. These include a discussion of the various ionization methods, mass analyzers, and tandem mass spectrometry (MS/MS) techniques that are used for structural characterization in a modern drug metabolism laboratory. Mass spectrometry-based techniques, such as stable isotope labeling, on-line H/D exchange, accurate mass measurement to enhance metabolite identification and recent improvements in data acquisition and processing for accelerating metabolite identification are also described. Rounding out this review, we offer additional thoughts about the potential of alternative and less frequently used techniques such as LC-NMR/MS, CRIMS and ICPMS. PMID:16787159

  10. Familial resemblance for serum metabolite concentrations.

    PubMed

    Draisma, Harmen H M; Beekman, Marian; Pool, René; van Ommen, Gert-Jan B; Adamski, Jerzy; Prehn, Cornelia; Vaarhorst, Anika A M; de Craen, Anton J M; Willemsen, Gonneke; Slagboom, P Eline; Boomsma, Dorret I

    2013-10-01

    Metabolomics is the comprehensive study of metabolites, which are the substrates, intermediate, and end products of cellular metabolism. The heritability of the concentrations of circulating metabolites bears relevance for evaluating their suitability as biomarkers for disease. We report aspects of familial resemblance for the concentrations in human serum of more than 100 metabolites, measured using a targeted metabolomics platform. Age- and sex-corrected monozygotic twin correlations, midparent-offspring regression coefficients, and spouse correlations in subjects from two independent cohorts (Netherlands Twin Register and Leiden Longevity Study) were estimated for each metabolite. In the Netherlands Twin Register subjects, who were largely fasting, we found significant monozygotic twin correlations for 121 out of 123 metabolites. Heritability was confirmed by midparent-offspring regression. For most detected metabolites, the correlations between spouses were considerably lower than those between twins, indicating a contribution of genetic effects to familial resemblance. Remarkably high heritability was observed for free carnitine (monozygotic twin correlation 0.66), for the amino acids serine (monozygotic twin correlation 0.77) and threonine (monozygotic twin correlation 0.64), and for phosphatidylcholine acyl-alkyl C40:3 (monozygotic twin correlation 0.77). For octenoylcarnitine, a consistent point estimate of approximately 0.50 was found for the spouse correlations in the two cohorts as well as for the monozygotic twin correlation, suggesting that familiality for this metabolite is explained by shared environment. We conclude that for the majority of metabolites targeted by the used metabolomics platform, the familial resemblance of serum concentrations is largely genetic. Our results contribute to the knowledge of the heritability of fasting serum metabolite concentrations, which is relevant for biomarker research. PMID:23985338

  11. Metabolism and metabolites of polychlorinated biphenyls (PCBs)

    PubMed Central

    Grimm, FA; Hu, D; Kania-Korwel, I; Lehmler, HJ; Ludewig, G; Hornbuckle, KC; Duffel, MW; Bergman, A; Robertson, LW

    2015-01-01

    The metabolism of polychlorinated biphenyls (PCBs) is complex and has an impact on toxicity and thereby assessment of PCB risks. A large number of reactive and stable metabolites are formed in the processes of biotransformation in biota in general and in humans in particular. The aim of this document is to provide an overview of PCB metabolism and to identify metabolites of concern and their occurrence. Emphasis is given to mammalian metabolism of PCBs and their hydroxyl, methylsulfonyl, and sulfated metabolites, especially those that persist in human blood. Potential intracellular targets and health risks are also discussed. PMID:25629923

  12. A wood preservative metabolite in river water.

    PubMed

    Khoroshko, Larisa O; Petrova, Varvara N; Viktorovskii, Igor V; Lahtiperä, Mirja; Sinkkonen, Seija; Paasivirta, Jaakko

    2005-01-01

    A previously unknown pollutant in river water was identified to be 2-mercaptobenzothiazole (2-MBT) by interpretation and simulation of its GC/LRMS spectrum. Further GC/HRMS measurement of the isotope composition of the molecular ion verified this structure. 2-MBT is a well-known agent for corrosion inhibition and a stable metabolite of several other benzothiazoles. The present 2-MBT trace was most probably a metabolite of the wood preservative TCMTB which leaked from an upstream sawmill. The metabolite had been detected earlier in urine of the sawmill workers, but now was identified in the recipient water environment for the first time. PMID:15768735

  13. Secondary metabolites from Rubiaceae species.

    PubMed

    Martins, Daiane; Nunez, Cecilia Veronica

    2015-01-01

    This study describes some characteristics of the Rubiaceae family pertaining to the occurrence and distribution of secondary metabolites in the main genera of this family. It reports the review of phytochemical studies addressing all species of Rubiaceae, published between 1990 and 2014. Iridoids, anthraquinones, triterpenes, indole alkaloids as well as other varying alkaloid subclasses, have shown to be the most common. These compounds have been mostly isolated from the genera Uncaria, Psychotria, Hedyotis, Ophiorrhiza and Morinda. The occurrence and distribution of iridoids, alkaloids and anthraquinones point out their chemotaxonomic correlation among tribes and subfamilies. From an evolutionary point of view, Rubioideae is the most ancient subfamily, followed by Ixoroideae and finally Cinchonoideae. The chemical biosynthetic pathway, which is not so specific in Rubioideae, can explain this and large amounts of both iridoids and indole alkaloids are produced. In Ixoroideae, the most active biosysthetic pathway is the one that produces iridoids; while in Cinchonoideae, it produces indole alkaloids together with other alkaloids. The chemical biosynthetic pathway now supports this botanical conclusion. PMID:26205062

  14. In situ bioavailability of DDT and Hg in sediments of the Toce River (Lake Maggiore basin, Northern Italy): accumulation in benthic invertebrates and passive samplers.

    PubMed

    Pisanello, Francesca; Marziali, Laura; Rosignoli, Federica; Poma, Giulia; Roscioli, Claudio; Pozzoni, Fiorenzo; Guzzella, Licia

    2016-06-01

    DDT and mercury (Hg) contamination in the Toce River (Northern Italy) was caused by a factory producing technical DDT and using a mercury-cell chlor-alkali plant. In this study, DDT and Hg contamination and bioavailability were assessed by using different approaches: (1) direct evaluation of sediment contamination, (2) assessment of bioaccumulation in native benthic invertebrates belonging to different taxonomic/functional groups, and (3) evaluation of the in situ bioavailability of DDT and Hg using passive samplers. Sampling sites were selected upstream and downstream the industrial plant along the river axis. Benthic invertebrates (Gammaridae, Heptageniidae, and Diptera) and sediments were collected in three seasons and analyzed for DDT and Hg content and the results were used to calculate the biota sediment accumulation factor (BSAF). Polyethylene passive samplers (PEs) for DDT and diffusive gradients in thin films (DGTs) for Hg were deployed in sediments to estimate the concentration of the toxicants in pore water. Analysis for (DDx) were performed using GC-MS. Accuracy was within ±30 % of the certified values and precision was >20 % relative standard deviation (RSD). Total mercury concentrations were determined using an automated Hg mercury analyzer. Precision was >5 % and accuracy was within ±10 % of certified values. The results of all the approaches (analysis of sediment, biota, and passive samplers) showed an increasing contamination from upstream to downstream sites. BSAF values revealed the bioavailability of both contaminants in the study sites, with values up to 49 for DDx and up to 3.1 for Hg. No correlation was found between values in sediments and the organisms. Concentrations calculated using passive samplers were correlated with values in benthic invertebrates, while no correlation was found with concentrations in sediments. Thus, direct analysis of toxicant in sediments does not provide a measurement of bioavailability. On the contrary

  15. Coping with shrub secondary metabolites by ruminants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangelands throughout the world contain varying but often substantial proportions of shrubs. Shrubs are generally heavily chemically defended, and herbivores must either contend with their plant secondary metabolites (PSM) or avoid a significant component of the available forage. Browsing ruminants ...

  16. The Significance of Lichens and Their Metabolites

    NASA Astrophysics Data System (ADS)

    Huneck, S.

    Lichens, symbiontic organisms of fungi and algae, synthesize numerous metabolites, the "lichen substances," which comprise aliphatic, cycloaliphatic, aromatic, and terpenic compounds. Lichens and their metabolites have a manifold biological activity: antiviral, antibiotic, antitumor, allergenic, plant growth inhibitory, antiherbivore, and enzyme inhibitory. Usnic acid, a very active lichen substance is used in pharmaceutical preparations. Large amounts of Pseudevernia furfuracea and Evernia prunastri are processed in the perfume industry, and some lichens are sensitive reagents for the evaluation of air pollution.

  17. Cellular toxicity of nicotinamide metabolites.

    PubMed

    Rutkowski, Bolesław; Rutkowski, Przemysław; Słomińska, Ewa; Smolenski, Ryszard T; Swierczyński, Julian

    2012-01-01

    There are almost 100 different substances called uremic toxins. Nicotinamide derivatives are known as new family of uremic toxins. These uremic compounds play a role in an increased oxidative stress and disturbances in cellular repair processes by inhibiting poly (ADP-ribose) polymerase activity. New members of this family were discovered and described. Their toxic properties were a subject of recent studies. This study evaluated the concentration of 4-pyridone-3-carboxamid-1-β-ribonucleoside-triphosphate (4PYTP) and 4-pyridone-3-carboxamid-1-β-ribonucleoside-monophosphate (4PYMP) in erythrocytes of patients with chronic renal failure. Serum and red blood cells were collected from chronic renal failure patients on conservative treatment, those treated with hemodialysis, and at different times from those who underwent kidney transplantation. Healthy volunteers served as a control group. Nicotinamide metabolites were determined using liquid chromatography with mass spectrometry based on originally discovered and described method. Three novel compounds were described: 4-pyridone-3-carboxamid-1-β-ribonucleoside (4PYR), 4PYMP, and 4PYTP. 4PYR concentration was elevated in the serum, whereas 4PYMP and 4PYTP concentrations were augmented in erythrocytes of dialysis patients. Interestingly, concentrations of these compounds were less elevated during the treatment with erythropoietin-stimulating agents (ESAs). After successful kidney transplantation, concentrations of 4PYR and 4PYMP normalized according to the graft function, whereas that of 4PYTP was still elevated. During the incubation of erythrocytes in the presence of 4PYR, concentration of 4PYMP rose very rapidly while that of 4PYTP increased slowly. Therefore, we hypothesized that 4PYR, as a toxic compound, was actively absorbed by erythrocytes and metabolized to the 4PYMP and 4PYTP, which may interfere with function and life span of these cells. PMID:22200423

  18. Transplacental transport of netobimin metabolites in ewes.

    PubMed

    Cristofol, C; Carretero, A; Fernandez, M; Navarro, M; Sautet, J; Ruberte, J; Arboix, M

    1995-01-01

    Neither netobimin (NTB) nor its metabolite albendazole (ABZ) were found in plasma after an oral administration of 20 mg/kg of NTB to pregnant ewes during the last third of gestation. ABZ metabolites, albendazole sulphoxide (ABZSO) and albendazole sulphone (ABZSO2) were found in plasma 30 min and 2 h, respectively, after administration. The maximal plasma concentration (Cmax) of ABZSO was detected at 11.6 +/- 1.0 h and for ABZSO2 at 16.5 +/- 2.3 h. The plasma levels of the latter remained constant for 36 h, and decreased as ABZSO was removed from the blood. Jugular plasma levels of both metabolites did not differ significantly from those observed in the ovarian vein, suggesting that there were no exchanges between foetal and placental tissues. Both metabolite concentrations were similar in the umbilical vein and artery and in the amniotic and allantoic fluids, their values were half the maternal plasma concentration, leading to the conclusion that there was transplacental movement of metabolites. Both metabolites reached the foetus and could be responsible for the teratogenicity of NTB in sheep. PMID:8751036

  19. Metabolites of cannabidiol identified in human urine.

    PubMed

    Harvey, D J; Mechoulam, R

    1990-03-01

    1. Urine from a dystonic patient treated with cannabidiol (CBD) was examined by g.l.c.-mass spectrometry for CBD metabolites. Metabolites were identified as their trimethylsilyl (TMS), [2H9]TMS, and methyl ester/TMS derivatives and as the TMS derivatives of the product of lithium aluminium deuteride reduction. 2. Thirty-three metabolites were identified in addition to unmetabolized CBD, and a further four metabolites were partially characterized. 3. The major metabolic route was hydroxylation and oxidation at C-7 followed by further hydroxylation in the pentyl and propenyl groups to give 1"-, 2"-, 3"-, 4"- and 10-hydroxy derivatives of CBD-7-oic acid. Other metabolites, mainly acids, were formed by beta-oxidation and related biotransformations from the pentyl side-chain and these were also hydroxylated at C-6 or C-7. The major oxidized metabolite was CBD-7-oic acid containing a hydroxyethyl side-chain. 4. Two 8,9-dihydroxy compounds, presumably derived from the corresponding epoxide were identified. 5. Also present were several cyclized cannabinoids including delta-6- and delta-1-tetrahydrocannabinol and cannabinol. 6. This is the first metabolic study of CBD in humans; most observed metabolic routes were typical of those found for CBD and related cannabinoids in other species. PMID:2336840

  20. Utilizing thin-film solid-phase extraction to assess the effect of organic carbon amendments on the bioavailability of DDT and dieldrin to earthworms

    USGS Publications Warehouse

    Andrade, Natasha A.; Centofanti, Tiziana; McConnell, Laura L.; Hapeman, Cathleen J.; Torrents, Alba; Anh, Nguyen; Beyer, W. Nelson; Chaney, Rufus L.; Novak, Jeffrey M.; Anderson, Marya O.; Cantrell, Keri B.

    2014-01-01

    Improved approaches are needed to assess bioavailability of hydrophobic organic compounds in contaminated soils. Performance of thin-film solid-phase extraction (TF-SPE) using vials coated with ethylene vinyl acetate was compared to earthworm bioassay (Lumbricus terrestris). A DDT and dieldrin contaminated soil was amended with four organic carbon materials to assess the change in bioavailability. Addition of organic carbon significantly lowered bioavailability for all compounds except for 4,4′-DDT. Equilibrium concentrations of compounds in the polymer were correlated with uptake by earthworms after 48d exposure (R2 = 0.97; p 40yr of aging. Results show that TF-SPE can be useful in examining potential risks associated with contaminated soils and to test effectiveness of remediation efforts.

  1. Undisturbed dust as a metric of long-term indoor insecticide exposure: Residential DDT contamination from indoor residual spraying and its association with serum levels in the VHEMBE cohort.

    PubMed

    Gaspar, Fraser W; Chevrier, Jonathan; Bornman, Riana; Crause, Madelein; Obida, Muvhulawa; Barr, Dana Boyd; Bradman, Asa; Bouwman, Henk; Eskenazi, Brenda

    2015-12-01

    Although approximately 123 million people may be exposed to high levels of insecticides through the use of indoor residual spraying (IRS) for malaria control, few studies exist on indoor insecticide contamination due to IRS and its relationship with human exposure. In the present study, we developed a sampling method to collect undisturbed dust from 50 homes in Limpopo, South Africa, a region where dichlorodiphenyltrichloroethane (DDT) has been used in IRS programs to prevent malaria for ~70years. We quantified DDT and its degradation products, dichlorodiphenyldichloroethylene (DDE), and dichlorodiphenyldichloroethane (DDD) in dust samples to determine dust loading levels and compared these levels to paired serum concentrations of p,p'-DDT and p,p'-DDE in women residents. p,p'-DDT and p,p'-DDE had the highest detection frequencies in both dust (58% and 34% detection, respectively) and serum samples (98% and 100% detection, respectively). Significantly higher detection frequencies for o,p'-DDT, p,p'-DDE, and p,p'-DDD were observed in dust samples collected in buildings that had been previously sprayed for malaria control. We also observed a significant, positive association between dust loading and serum concentrations of p,p'-DDT and p,p'-DDE (Spearman's rho=0.68 and 0.54, respectively). Despite the low detection frequency in dust, our results indicate that undisturbed dust may be a good metric to quantify long-term home exposure to DDT-related compounds and that contamination of the home environment may be an important determinant/source of DDT and DDE exposure. PMID:26398044

  2. Effects of o,p'-DDT on the 2,3,7,8-tetrachlorodibenzo-p-dioxin-inducible CYP1A1 expression in murine Hepa-1c1c7 cells.

    PubMed

    Jeong, Hye Gwang; Kim, Ji Young

    2002-11-01

    Cultured mouse hepatoma Hepa-1c1c7 cells were treated with o,p'-DDT and/or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to assess the role of o,p'-DDT on CYP1A1 expression. o,p'-DDT alone did not affect CYP1A1-specific 7-ethoxyresorufin O-deethylase (EROD) activity. In contrast, TCDD-inducible EROD activities were markedly reduced on concomitant treatment with TCDD and o,p'-DDT in a dose-dependent manner. Treatment with ICI 182.780, an estrogen-receptor antagonist, did not affect the suppressive effects of o,p'-DDT on TCDD-inducible EROD activity. TCDD-inducible CYP1A1 mRNA levels were markedly suppressed on treatment with TCDD and o,p'-DDT, and this was consistent with their effects on EROD activity. A transient transfection assay using dioxin-response element (DRE)-linked luciferase and an electrophoretic mobility shift assay revealed that o,p'-DDT reduced the transformation of the aryl hydrocarbons (Ah) receptor to a form capable of specifically binding to the DRE sequence in the promoter region of the CYP1A1 gene. These results suggest that the downregulation of CYP1A1 gene expression by o,p'-DDT in Hepa-1c1c7 cells might be an antagonism of the DRE binding potential of the nuclear Ah receptor but is not mediated through the estradiol receptor. PMID:12176094

  3. Impact of permethrin-impregnated mosquito nets compared with DDT house-spraying against malaria transmission by Anopheles farauti and An.punctulatus in the Solomon Islands.

    PubMed

    Hii, J L; Kanai, L; Foligela, A; Kan, S K; Burkot, T R; Wirtz, R A

    1993-10-01

    In villages of northern Guadalcanal in the Solomon Islands, where the predominant malaria vector is An.farauti No. 1 and An.puctulatus is also involved, malaria transmission rates were compared for three zones: (1) non-intervention: 438 people in seventeen villages; (2) residual DDT house-spraying two cycles per year: 644 people in thirty villages; (3) bednets impregnated with permethrin 0.5 g/m2 twice per year, used by 580 people in sixteen villages. Regular DDT spraying in zones 1 and 3 had been withdrawn 18 months previously. Malariological blood smear surveys of children aged 1-9 years in August 1986 to January 1987 showed a mean baseline malaria parasite rate of 38% (32/84). By February 1988, 18 months after introduction of impregnated bednets, the Plasmodium falciparum infection rate in children was lowest in the zone using impregnated bednets (21% of 29), intermediate in the untreated zone (29% of 34) and highest in the DDT zone (46% of 53), but these differences were not statistically significant. P. vivax infection rates were 9-14%. Using ELISA tests for malaria circumsporozoite antigen in the vectors, overall positivity rates were 0.7% of 49,902 An.farauti and 2.54% of 118 An.punctulatus, comprising 228 P.falciparum and 124 P.vivax infections. In the study zones, vector positivity rates were 0.93% of 31,615 An.farauti in the untreated zone; 0.32% of 16,883 An.farauti in the DDT zone; 0.07% of 1404 An.farauti and 2.54% of 118 An.puctulatus in the impregnated bednet zone. here was no significant correlation between malaria parasite rates in the vectors and the children.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8268487

  4. Distribution, sources and potential risk of HCH and DDT in soils from a typical alluvial plain of the Yangtze River Delta region, China.

    PubMed

    Hu, Wenyou; Huang, Biao; Zhao, Yongcun; Sun, Weixia; Gu, Zhiquan

    2014-06-01

    Spatial distribution, sources and potential health risks of organochlorine pesticides (OCPs), including hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT), in surface soils (n = 544) collected from a typical alluvial plain of the Yangtze River Delta region, China, were elucidated. Concentrations of ΣHCH and ΣDDT in soils ranged from less than the limit of detection (DDT were the major sources of the residue in soils. HCH was mainly distributed in Anthrosols in the southern part of the watershed, while DDT was mainly distributed in Cambosols in the northern part. The 95 % cumulative probability incremental lifetime cancer risks (ILCRs) of different age groups such as children, youths, and adults all exceeded the acceptable risk level of 10(-6) recommended by USEPA for carcinogenic chemicals. The spatial distributions of ∑ILCRs were consistent with concentrations of OCPs in soils, while they were slight different for the different age groups. Adult females had the greatest risk of OCPs in soils, followed by children, while youths had the least risk. The ingestion of OCPs in soils was the more important route of exposure compared with dermal and inhalation exposures. The concentration of OCPs in soils, the particulate emission factor, the fraction of dermal exposure ratio, and the soil ingestion rate were the major contributing variables to total ILCRs according to sensitivity analyses. PMID:23880843

  5. Temporal trends and spatial distribution of DDT in bivalves from the coastal marine environments of the continental United States, 1986-2009.

    PubMed

    Sericano, José L; Wade, Terry L; Sweet, Stephen T; Ramirez, Juan; Lauenstein, Gunnar G

    2014-04-30

    Analysis of DDT isomers and breakdown products, DDD and DDE, in over 3500 bivalve samples collected from more than 300 locations along the continental United States indicates that concentrations are decreasing. Overall average concentrations for the East (45.8±24.6 ng/gdw), Gulf (42.4±21.1 ng/gdw), and West (90.9±43.3ng/gdw) coasts are declining with an environmental half-life between 10 and 14 ears and are predicted to decrease below 10% of today's concentrations by 2050. Geographically, areas with high and low levels are well identified. Bivalves yielding the highest concentrations were collected in areas linked to areas of DDT production or heavy usage. These areas are clustered in the southern California and San Francisco area, on the West coast; Delaware and Hudson/Raritan Estuary, on the East coast; and in Alabama and northwestern Florida, on the Gulf of Mexico. Statistically significant decreasing trends in ΣDDT concentrations are apparent at most of these locations. PMID:24655944

  6. Evaluation of a first-order model for the prediction of the bioaccumulation of PCBs and DDT from sediment into the marine deposit-feeding clam Macoma nasuta

    SciTech Connect

    Boese, B.L.; Lee, H. II; Echols, S.

    1997-07-01

    A first-order model for predicting contaminant bioaccumulation from sediments into benthic invertebrates was validated using a marine deposit-feeding clam, Macoma nasuta, exposed to polychlorobiphenyl (PCB)-spiked and dichlorodiphenyltrichloroethane (DDT)-contaminated sediments. Contaminant uptake and depuration were analyzed following short-term and long-term sediment exposures. Uptake and depuration rates were used to predict steady-state bioaccumulation factors (BAFs) and exposure times needed to attain steady state. These predictions were compared to observed steady-state BAFs. Estimating elimination and uptake rates from depuration and short-term uptake experiments was an accurate means of predicting BAFs for some PCBs but was not as accurate for predicting DDT BAFs. The exposure time need to attain steady state was poorly predicted by the model. The results demonstrated that a standard 28-d bioaccumulation test estimated steady-state tissue residues within two-fold and was a better predictor than the model for the BAFs of superlipophilic PCBs (log K{sub ow} > 7). Differences in contaminant bioavailability were noted between field-contaminated (DDT) and laboratory-spiked (PCB) sediments.

  7. Adsorptive performance and catalytic activity of superparamagnetic Fe3O4@nSiO2@mSiO2 core-shell microspheres towards DDT.

    PubMed

    Liu, Feng; Tian, Hua; He, Junhui

    2014-04-01

    Due to specific properties, core-shell Fe3O4@SiO2 and core-shell-shell Fe3O4@nSiO2@mSiO2 nanostructures have been extensively investigated for the contamination treatment of wastewater. However, these reported materials were usually used as advanced adsorbents or catalyst-supports. In this study, we demonstrate that magnetic mesoporous silica Fe3O4@nSiO2@mSiO2 microspheres can not only exhibit excellent adsorptive performance for removal of DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane) from aqueous media, but also display high catalytic activity. Over 97% of DDT could be quickly removed from aqueous media in 60 min. At 60°C the DDE (1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene) content increases greatly as DDT disappears completely, and is decomposed completely after thermal treatment at a relatively low temperature of 450°C. The obtained magnetic mesoporous silica nanoparticles were characterized by X-ray diffraction, transmission electron microscopy, nitrogen adsorption-desorption measurements and vibrating sample magnetometer. The results indicate that Fe3O4@nSiO2@mSiO2 microspheres show strong superparamagnetism and have high specific surface area (577 m(2) g(-1)). PMID:24491332

  8. Exposure pathways to HCH and DDT in Cidade dos Meninos and its surrounding districts of Amapa, Figueiras and Pilar, metropolitan regions of Rio de Janeiro, Brazil.

    PubMed

    Brilhante, Ogenis M; Franco, Robson

    2006-06-01

    In 1989, the Rio de Janeiro State environmental agency (FEEMA) after a preliminary survey of the site known as Cidade dos Meninos, collected and disposed in a safe area tons of a pesticide that was spread in and around the ruins of an old hexachlorocyclohexane (HCH) factory. The aim of this article is three-fold: (i) To investigate the existing HCH and DDT contamination levels in soil, water, air, vegetables and grasses at the Cidade dos Meninos site and the surrounding districts of Amapa, Figueiras and Pilar; (ii) To identify the main environmental exposure pathways present in the study area, and (iii) To propose a health hazard classification for this area. The results showed the presence of high levels of total HCH and DDT in the environmental media samples, especially in those collected in the district Cidade dos Meninos. This district is also the one that produces more food (vegetables, milk and meat) for local and outside population. The environmental data correlated to the socio-economic, food diet and local health conditions led to the identification of four complete exposure pathways to HCH and DDT (surface soil, access road, food chain and ambient air). Using the ATSDR (1996) and Magalhães (2000) criteria the site was classified in two public health hazard categories: Category II - hazard for public health, and category III - indeterminate hazard for public health. PMID:16611565

  9. Ecological bioavailability of permethrin and p,p'-DDT: toxicity depends on type of organic matter resource.

    PubMed

    de Perre, Chloé; Trimble, Andrew J; Maul, Jonathan D; Lydy, Michael J

    2014-02-01

    Hydrophobic organic contaminants readily partition from aqueous to organic phases in aquatic systems with past research largely focusing on sediment. However, within many aquatic systems, matrices such as leaf material and detritus are abundant and ecologically important, as they may represent a primary exposure route for aquatic invertebrates. The objectives of the present study were to examine partitioning and toxicity to Hyalella azteca among permethrin and p,p'-DDT contaminated sediment, leaf, and a sediment-leaf mixture. Log organic carbon-water partitioning coefficients ranged from 4.21 to 5.82 for both insecticides, and were greatest within sediment and lowest in coarse leaf material. H. azteca lethal concentrations for 50% of the population (LC50s) ranged from 0.5 to 111μgg(-1) organic carbon, and were dependent on the matrix composition. The variation in sorption and toxicity among matrices common within stream ecosystems suggests that the ecological niche of aquatic organisms may be important for estimating risk of hydrophobic pesticides. PMID:23948608

  10. Oral relative bioavailability of Dichlorodiphenyltrichloroethane (DDT) in contaminated soil and its prediction using in vitro strategies for exposure refinement.

    PubMed

    Juhasz, Albert L; Herde, Paul; Smith, Euan

    2016-10-01

    In this study, the bioavailability of DDTr (sum of DDT, DDD and DDE isomers) in pesticide-contaminated soil was assessed using an in vivo mouse model. DDTr relative bioavailability (RBA) ranged from 18.7±0.9 (As35) to 60.8±7.8% (As36) indicating that a significant portion of soil-bound DDTr was not available for absorption following ingestion. When DDTr bioaccessibility was assessed using the organic Physiologically Based Extraction Test (org-PBET), the inclusion of a sorption sink (silicone cord) enhanced DDTr desorption by up to 20-fold (1.6-3.8% versus 18.9-56.3%) compared to DDTr partitioning into gastrointestinal fluid alone. Enhanced desorption occurred as a result of the silicone cord acting as a reservoir for solubilized DDTr to partition into, thereby creating a flux for further desorption until equilibrium was achieved. When the relationship between in vivo and in vitro data was assessed, a strong correlation was observed between the mouse bioassay and the org-PBET+silicone cord (slope=0.94, y-intercept=3.5, r(2)=0.72) suggesting that the in vitro approach may provide a robust surrogate measure for the prediction of DDTr RBA in contaminated soil. PMID:27423050

  11. A Simple Colorimetric Assay for Specific Detection of Glutathione-S Transferase Activity Associated with DDT Resistance in Mosquitoes

    PubMed Central

    Rajatileka, Shavanti; Steven, Andrew; Hemingway, Janet; Ranson, Hilary; Paine, Mark; Vontas, John

    2010-01-01

    Background Insecticide-based methods represent the most effective means of blocking the transmission of vector borne diseases. However, insecticide resistance poses a serious threat and there is a need for tools, such as diagnostic tests for resistance detection, that will improve the sustainability of control interventions. The development of such tools for metabolism-based resistance in mosquito vectors lags behind those for target site resistance mutations. Methodology/Principal Findings We have developed and validated a simple colorimetric assay for the detection of Epsilon class Glutathione transferases (GST)-based DDT resistance in mosquito species, such as Aedes aegypti, the major vector of dengue and yellow fever worldwide. The colorimetric assay is based on the specific alkyl transferase activity of Epsilon GSTs for the haloalkene substrate iodoethane, which produces a dark blue colour highly correlated with AaGSTE2-2-overexpression in individual mosquitoes. The colour can be measured visually and spectrophotometrically. Conclusions/Significance The novel assay is substantially more sensitive compared to the gold standard CDNB assay and allows the discrimination of moderate resistance phenotypes. We anticipate that it will have direct application in routine vector monitoring as a resistance indicator and possibly an important impact on disease vector control. PMID:20824165

  12. "God bless General Péron": DDT and the endgame of malaria eradication in Argentina in the 1940s.

    PubMed

    Carter, Eric D

    2009-01-01

    This article explores the politics of malaria eradication in Argentina during the first government of Juan D. Perón. The article develops the theme of historical convergence to understand the rapid mobilization and success of the climactic battle against malaria in Northwest Argentina. The nearly complete eradication of malaria in Argentina resulted from a combination of three factors. First, Carlos Alvarado, the director of Argentina's Malaria Service, had already developed a solid but flexible organizational base that allowed a dramatic change in control strategy. Second, an infusion of new technologies, especially DDT but also motor vehicles, was instrumental. Lastly, a radical reorientation of national public health policy in the 1940s, under the direction of Perón and his health minister, Ramón Carrillo, encouraged eradication. These figures embraced and refashioned long-standing organicist ideologies that hitched the strength of the nation-state to the health and vigor of its ordinary citizens. This ideological orientation was reflected in bold, populist political strategies that showcased swift, massive, and expensive public health campaigns, including malaria eradication. In the conclusion, the article explores the ambiguous connections between malaria eradication and an ecological perspective on the disease. PMID:18812412

  13. [Secondary Metabolites from Marine Microorganisms. I. Secondary Metabolites from Marine Actinomycetes].

    PubMed

    Orlova, T I; Bulgakova, V G; Polin, A N

    2015-01-01

    Review represents data on new active metabolites isolated from marine actinomycetes published in 2007 to 2014. Marine actinomycetes are an unlimited source of novel secondary metabolites with various biological activities. Among them there are antibiotics, anticancer compounds, inhibitors of biochemical processes. PMID:26863742

  14. Permanent and functional male-to-female sex reversal in d-rR strain medaka (Oryzias latipes) following egg microinjection of o,p'-DDT.

    PubMed Central

    Edmunds, J S; McCarthy, R A; Ramsdell, J S

    2000-01-01

    Complete sex reversal of fish is accomplished routinely in aquaculture practices by exposing fish to exogenous sex steroids during gonadal differentiation. A variety of environmental chemicals are also active at sex steroid receptors and theoretically possess the potential to alter normal sexual differentiation in fish. However, in controlled environmental chemical exposures to date, only partial alterations of fish sexual phenotype have been observed. Here we report complete, permanent, and functional male-to-female sex reversal in the Japanese medaka (Oryzias latipes, d-rR strain) after a onetime embryonic exposure to the xenoestrogen o, p'-DDT. d-rR strain medaka are strict gonochorists that possesses both sex-linked pigmentation, which distinguishes genotypic sex, and sexually dimorphic external secondary sexual characteristics, which distinguish phenotypic sex. We directly microinjected the xenoestrogen o, p'-DDT into the egg yolks of medaka at fertilization to parallel the maternal transfer of lipophilic contaminants to the embryo. At 10 weeks of age, microinjected medaka were examined for mortality and sex reversal. A calculated embryonic dose of 511 +/- 22 ng/egg o, p'-DDT (mean +/- standard error) resulted in 50% mortality. An embryonic exposure of 227 +/- 22 ng/egg o, p'-DDT resulted in 86% (6 of 7) sex reversal of genetic males to a female phenotype (XY females). XY females were distinguished by sex-linked male pigmentation accompanying female secondary sexual characteristics. Histologic examination of the gonads confirmed active ovaries in 100% of the XY females. In 10-day breeding trials in which XY females were paired with normal XY males, 50% of the XY females produced fertilized embryos; this represents a comparable breeding success rate to normal XX females. Fertilized eggs produced from XY females hatched to viable larvae. These results clearly indicate that a weakly estrogenic pesticide, o, p'-DDT, when presented during the critical period of

  15. Prenatal Exposure to p,p′-DDE and p,p′-DDT in Relation to Lower Respiratory Tract Infections in Boys From a Highly Exposed Area of Mexico

    PubMed Central

    Cupul-Uicab, Lea A.; Terrazas-Medina, Efraín A.; Hernández-Ávila, Mauricio; Longnecker, Matthew P.

    2014-01-01

    Background Prenatal exposure to 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p′-DDE), the major breakdown product of DDT, has been associated with recurrent lower respiratory tract infections (LRTI) in infants. However, epidemiological investigations are limited. Objective To assess the association of prenatal exposure to p,p′-DDE and p,p′-DDT with the occurrence of LRTI in boys from Chiapas, a highly exposed area of Mexico. Methods We analyzed data from 747 singleton boys whose prenatal exposure to p,p′-DDE and p,p′-DDT was determined in maternal serum drawn at delivery (2002–2003). LRTI (i.e., pneumonia, bronchiolitis, and other illness of the bronchi) experienced by the children were reported by their mothers during in-person interviews. The median age of the children when they were last seen was 21.4 months (quartiles 19.1 and 25.3 months). Results Median exposure to p,p′-DDE in this population was higher (2.7 μg/g lipid) than recent U.S. levels (0.20 μg/g). There were 0.19 episodes of LRTI per child-year. After adjusting for potential confounders, children in the highest category of p,p′-DDE (>9.00 μg/g) exposure compared to those in the lowest (≤3.00 μg/g) had an adjusted incidence rate ratio (aIRR) of LRTI of 0.77 (95% confidence interval [CI], 0.41–1.46). The corresponding aIRR for p,p′-DDT (≥2.00 μg/g compared to ≤0.25 μg/g) was 0.65 (95% CI: 0.30–1.39). Conclusion An association of prenatal exposure to p,p′-DDE and p,p′-DDT with LRTI during childhood was not supported in this population with relatively high levels of exposure. PMID:24742723

  16. Secondary metabolites in fungus-plant interactions

    PubMed Central

    Pusztahelyi, Tünde; Holb, Imre J.; Pócsi, István

    2015-01-01

    Fungi and plants are rich sources of thousands of secondary metabolites. The genetically coded possibilities for secondary metabolite production, the stimuli of the production, and the special phytotoxins basically determine the microscopic fungi-host plant interactions and the pathogenic lifestyle of fungi. The review introduces plant secondary metabolites usually with antifungal effect as well as the importance of signaling molecules in induced systemic resistance and systemic acquired resistance processes. The review also concerns the mimicking of plant effector molecules like auxins, gibberellins and abscisic acid by fungal secondary metabolites that modulate plant growth or even can subvert the plant defense responses such as programmed cell death to gain nutrients for fungal growth and colonization. It also looks through the special secondary metabolite production and host selective toxins of some significant fungal pathogens and the plant response in form of phytoalexin production. New results coming from genome and transcriptional analyses in context of selected fungal pathogens and their hosts are also discussed. PMID:26300892

  17. Metabolite profiles during oral glucose challenge.

    PubMed

    Ho, Jennifer E; Larson, Martin G; Vasan, Ramachandran S; Ghorbani, Anahita; Cheng, Susan; Rhee, Eugene P; Florez, Jose C; Clish, Clary B; Gerszten, Robert E; Wang, Thomas J

    2013-08-01

    To identify distinct biological pathways of glucose metabolism, we conducted a systematic evaluation of biochemical changes after an oral glucose tolerance test (OGTT) in a community-based population. Metabolic profiling was performed on 377 nondiabetic Framingham Offspring cohort participants (mean age 57 years, 42% women, BMI 30 kg/m(2)) before and after OGTT. Changes in metabolite levels were evaluated with paired Student t tests, cluster-based analyses, and multivariable linear regression to examine differences associated with insulin resistance. Of 110 metabolites tested, 91 significantly changed with OGTT (P ≤ 0.0005 for all). Amino acids, β-hydroxybutyrate, and tricarboxylic acid cycle intermediates decreased after OGTT, and glycolysis products increased, consistent with physiological insulin actions. Other pathways affected by OGTT included decreases in serotonin derivatives, urea cycle metabolites, and B vitamins. We also observed an increase in conjugated, and a decrease in unconjugated, bile acids. Changes in β-hydroxybutyrate, isoleucine, lactate, and pyridoxate were blunted in those with insulin resistance. Our findings demonstrate changes in 91 metabolites representing distinct biological pathways that are perturbed in response to an OGTT. We also identify metabolite responses that distinguish individuals with and without insulin resistance. These findings suggest that unique metabolic phenotypes can be unmasked by OGTT in the prediabetic state. PMID:23382451

  18. Transporter and its engineering for secondary metabolites.

    PubMed

    Lv, Huajun; Li, Jianhua; Wu, Yingying; Garyali, Sanjog; Wang, Yong

    2016-07-01

    Secondary metabolites possess a lot of biological activities, and to achieve their functions, transmembrane transportation is crucial. Elucidation of their transport mechanisms in the cell is critical for discovering ways to improve the production. Here, we have summarized the recent progresses for representative secondary metabolite transporters and also the strategies for uncovering the transporter systems in plants and microbes. We have also discussed the transporter engineering strategies being utilized for improving the heterologous natural product production, which exhibits promising future under the guide of synthetic biology. PMID:27209041

  19. [Autism and Autism-associated Metabolites].

    PubMed

    Watanabe, Kunitomo

    2016-06-01

    Gene-microbiota interactions are now proposed to be a special case of gene-environmental interaction. Preclinical and clinical data summarized in this article reveal that a specific serum metabolite, associated with alterations in gut microbiome composition, might have an emerging role in the onset and pathogenesis of autism. Altered level of this specified metabolite may induce perturbations in the epigenome and modulate the expression of key disease susceptible genes in neurons and their associated cells during critical periods of neurodevelopment. The gut microbiota itself is now regarded as a reservoir for environmental epigenetic factors. PMID:27279160

  20. Streptomyces metabolites in divergent microbial interactions.

    PubMed

    Takano, Hideaki; Nishiyama, Tatsuya; Amano, Sho-ichi; Beppu, Teruhiko; Kobayashi, Michihiko; Ueda, Kenji

    2016-03-01

    Streptomyces and related bacteria produce a wide variety of secondary metabolites. Of these, many compounds have industrial applications, but the question of why this group of microorganism produces such various kinds of biologically active substances has not yet been clearly answered. Here, we overview the results from our studies on the novel function and role of Streptomyces metabolites. The diverged action of negative and positive influences onto the physiology of various microorganisms infers the occurrence of complex microbial interactions due to the effect of small molecules produced by Streptomyces. The interactions may serve as a basis for the constitution of biological community. PMID:26408311

  1. The relationship between reproductive outcome measures in DDT exposed malaria vector control workers: a cross-sectional study

    PubMed Central

    Dalvie, Mohamed A; Myers, Jonathan E

    2006-01-01

    Background The utility of blood reproductive endocrine biomarkers for assessing or estimating semen quality was explored. Methods A cross-sectional study of 47 DDT exposed malaria vector control workers was performed. Tests included blood basal and post gonadotrophin releasing hormone (GnRH), lutenizing hormone (LH), follicle stimulating hormone (FSH), testosterone, sex hormone binding globulin (SHBG), estradiol (E2) and inhibin; a questionnaire (demographics and general medical history); a physical examination and semen analysis. Semen parameters were determined using either/or or both WHO or the strict Tygerberg criteria. Relationships between semen parameters and endocrine measures were adjusted for age, duration of abstinence before sampling, presence of physical abnormalities and fever in the last two months. All relationships between specific endocrine hormones were adjusted for age and basal SHBG. Results Multiple logistic regression showed a consistent positive relationship (prevalence odds ratio (POR) = 8.2, CI:1.4–49.2) between low basal inhibin (<100 pg/ml) and low semen count (< 40 million) and density (< 20 million/ml); consistent positive, but weaker relationships (1> POR < 2) between abnormally low semen count as well as density and baseline and post GnRH FSH; and positive relationships (POR = 37, CI:2–655) between the prevalence of high basal estradiol (> 50 pg/ml) and abnormal morphology (proportion < 5%) and low motility (proportion <50%). Most of the expected physiological relationships between specific endocrines were significant. Conclusion The study has demonstrated that low basal inhibin, elevated basal FSH and high basal E2 can serve as markers of impaired semen quality. PMID:16901337

  2. Combined remediation of DDT congeners and cadmium in soil by Sphingobacterium sp. D-6 and Sedum alfredii Hance.

    PubMed

    Fang, Hua; Zhou, Wei; Cao, Zhengya; Tang, Feifan; Wang, Dandan; Liu, Kailin; Wu, Xiangwei; Yang, Xiao'e; Sun, Yongge; Yu, Yunlong

    2012-01-01

    Combined pollution of 1,1,1-trichloro-2,2-bis (4-chlorophenyl) ethane (DDT) and cadmium (Cd) in agricultural soils is of great concern because they present serious risk to food security and human health. In order to develop a cost-effective and safe method for the removal of DDTs and Cd in soil, combined remediation of DDTs and Cd in soil by Sphingobacterium sp. D-6 and the hyperaccumulator, Sedum alfredii Hance was investigated. After treatment for 210 days, the degradation half-lives of DDTs in soils treated by strain D-6 decreased by 8.1% to 68.0% compared with those in the controls. The inoculation of strain D-6 into soil decreased the uptake of DDTs by pak choi and S. alfredii. The shoots/roots ratios of S. alfredii for the Cd accumulation ranged from 12.32 to 21.75. The Cd concentration in soil decreased to 65.8%-71.8% for S. alfredii treatment and 14.1%-58.2% for S. alfredii and strain D-6 combined treatment, respectively, compared with that in the control. The population size of the DDTs-degrading strain, Simpson index (1/D) and soil respiratory rate decreased in the early stage of treatment and then gradually increased, ultimately recovering to or exceeding the initial level. The results indicated that synchronous incorporation of strain D-6 and S. alfredii into soil was found to significantly (p < or = 0.05) enhance the degradation of DDTs in soil and the hyperaccumulation of Cd in S. alfredii. It was concluded that strain D-6 and S. alfredii could be used successfully to control DDTs and Cd in contaminated soil. PMID:23505871

  3. Organochlorine pesticides and their metabolites in human breast milk from Shanghai, China.

    PubMed

    Lu, Dasheng; Wang, Dongli; Ni, Rong; Lin, Yuanjie; Feng, Chao; Xu, Qian; Jia, Xiaodong; Wang, Guoquan; Zhou, Zhijun

    2015-06-01

    Organochlorine pesticides (OCPs) are persistent organic pollutants that could cause deleterious effects on human health. Breast milk represents a noninvasive specimen source to assess maternal and infant exposure to OCPs. This study recruited 142 pregnant mothers in 2011-2012 in Shanghai, China, and their breast milk samples were collected during lactation and analyzed for 27 OCP compounds. Detection rates were in a range of 65.5 to 100 %. In particular, metabolites of 2,2-bis(chlorophenyl)-1,1,1-trichloroethane (DDT) such as 2-chloro-1,1-bis(4-chlorophenyl)ethylene (DDMU), 2,2-bis(4-chlorophenyl)ethanol (DDOH), bis(4-chlorophenyl)ketone (DBP), and 4,4'-dichlorodiphenylmethane (DDM) were detected in most milk samples. DDTs, hexachlorobenzene (HCB), and hexachlorocyclohexane (HCH) were dominant OCPs with mean levels of 316, 49.8, and 41.5 ng/g lipid content, respectively, whereas levels of methoxychlor, ∑Drins, ∑Heptachlor, ∑Chlordane, and ∑Endosulfan were fairly low (0.87-5.6 ng/g lipid content). Milk concentrations of OCPs were weakly correlated with maternal age, body weight, and body mass indexes (BMIs). ∑OCPs in this study were much lower than those in human breast milk samples collected in 2002 and 2007. Consumption of higher amounts of fish was associated with higher milk levels of OCPs. Specific OCP patterns in breast milk samples from migrant mothers in Shanghai reflected features of OCP production, use, and exposure in their home provinces. The probabilistic exposure assessment model reveals that Shanghai infants were exposed to low levels of OCPs through breast milk consumption. However, infants as the vulnerable group might be subject to the potential additive and/or synergistic health effects from complex OCP exposure. PMID:25595932

  4. Serum albumin complexation of acetylsalicylic acid metabolites.

    PubMed

    Jurkowski, Wiktor; Porebski, Grzegorz; Obtułowicz, Krystyna; Roterman, Irena

    2009-06-01

    One possible origin of the type I hypersensitivity reaction is reaction of drugs such as acetylsalicylic acid and its metabolites being complexed with human serum albumin. Albumin, being transporting molecule abundant in blood plasma is able to bind large array of ligands varying from small single carbon particles to long hydrophobic tailed lipidic acids (e.g. myristic acid). This non specificity is possible because of multi domain scaffold and large flexibility of inter-domain loops, which results in serious reorientation of domains. Hypothesis that acetylsalicylic acid metabolites may play indirect role in activation of allergic reaction has been tested. Binding of acetylsalicylic acid metabolites in intra-domain space causes significant increase of liability of domains IIIA and IIIB. One of metabolites, salicyluric acid, once is bound causes distortion and partial unfolding of helices in domains IA, IIB and IIIB. Changed are both directions and amplitude of relative motions as well as intra-domain distances. In result albumin is able to cross-link of adjacent IgE receptors which subsequently starts allergic reaction. PMID:19689242

  5. Aspirin-triggered metabolites of EFAs.

    PubMed

    Makriyannis, Alexandros; Nikas, Spyros P

    2011-10-28

    Aspirin triggers the biosynthesis of oxygenated metabolites from arachidonic, eicosapentaenoic, and docosahexaenoic (DHA) acids. In a preceding issue, Serhan et al. (2011) describe a novel aspirin-triggered DHA pathway for the biosynthesis of a potent anti-inflammatory and proresolving molecule. PMID:22035788

  6. Microbial metabolism part 13 metabolites of hesperetin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungal culture, Mucor ramannianus (ATCC 2628) transformed hesperitin to four metabolites: 4'-methoxy -5, 7, 8, 3'-tetrahydroxyflavanone (8-hydroxyhesperetin), 5, 7, 3', 4'-tetrahydroxyflavanone (eriodictyol), 4'-methoxy-5, 3'-dihydroxyflavanone 7-sulfate (hesperetin 7-sulfate) and 5, 7, 3'-tri...

  7. Eleven microbial metabolites of 6-hydroxyflavanone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    6-Hydroxyflavanone (1) when fermented with fungal culture Cunninghamella blakesleeana (ATCC 8688a) yielded flavanone 6-O-ß-D-glucopyranoside (2), flavanone 6-sulfate (3), and 6-hydroxyflavanone 7-sulfate (4). Aspergillus alliaceus (ATCC 10060) also transformed 1 to metabolite 3 as well as 4'-hydrox...

  8. [Recent observations on the sensitivity to pyrethroids and DDT of Anopheles arabiensis and Anopheles funestus in the central Highlands of Madagascar; preliminary results on the absence of the kdr mutation in An. arabiensis].

    PubMed

    Ratovonjato, J; Le Goff, G; Rajaonarivelo, E; Rakotondraibe, E M; Robert, V

    2003-01-01

    Anopheles arabiensis and Anopheles funestus are the principal vectors of malaria on the central highlands of Madagascar. These two species of mosquito are directly or indirectly the targets of indoor insecticide spread. The survey of the susceptibility of these two vectors to insecticides is essential specifying for the anti-vectorial current directives and for the future programs. This paper describes: --the recent tests of susceptibility and the study of the knock-down effect of four pyrethroids (deltamethrin 0.50%, permethrin 0.250%, alpha-cypermethrin 0.025%, cyfluthrin 0.150%) and DDT 4% on An. arabiensis collected from December 2002 to May 2003 in three villages on the district of Tsiroanomandidy and in Alasora, a rural area near the capital, Antananarivo. --the susceptibility tests of An. funestus realised in Morafeno, against cyfluthrin 0.150%, deltaméthrin 0.050%, lambda-cyhalothrin 0.050% and DDT 4%. --the preliminary study of the kdr gene mutation, which might account for the pyrethrinoid and DDT resistance, of An. arabiensis in Alasora. The data indicate a decrease in the efficiency of alpha-cypermethrin 0.025% (Tkd99 = 21 mn) and of DDT 4% (Tkd99 = 191.5 mn) on An. arabiensis in Analamiranga. Nevertheless, the effectiveness of permethrin 0.250% has been notified. In Soanierana, alpha-cypermethrin 0.025% was effective against An. arabiensis, whilst the ineffectiveness of the DDT 4% (Tkd99 = 116 mn) in Andranonahoatra was observed. In Alasora, a fall in the effectiveness of alpha-cypermethrin 0.025% (Tkd99 = 21 mn) and the resistance to DDT 4% (Tkd99 = 6894 mn) was noted. No kdr mutation was detected on the kd gene of An. arabiensis resistant to the alpha-cypermethrin 0.025% and to DDT 4%, collected in Alasora. An. funestus collected in the district of Miandrivazo is susceptible to pyrethroids and to DDT. To conclude, in the Malagasy Central Highlands, An. arabiensis is ordinary sensitive to pyrethroid and poorly sensitive, or even resistant to DDT (as

  9. METLIN: MS/MS metabolite data from the MAGGIE Project

    DOE Data Explorer

    METLIN is a metabolite database for metabolomics containing over 50,000 structures, it also represents a data management system designed to assist in a broad array of metabolite research and metabolite identification by providing public access to its repository of current and comprehensive MS/MS metabolite data. An annotated list of known metabolites and their mass, chemical formula, and structure are available on the METLIN website. Each metabolite is conveniently linked to outside resources such as the the Kyoto Encyclopedia of Genes and Genomes (KEGG) for further reference and inquiry. MS/MS data is also available on many of the metabolites. The list is expanding continuously as more metabolite information is being deposited and discovered. [from http://metlin.scripps.edu/] Metlin is a component of the MAGGIE Project. MAGGIE is funded by the DOE Genomics: GTL and is an acronym for "Molecular Assemblies, Genes, and Genomics Integrated Efficiently."

  10. ALGAL METABOLITE INFLUENCE ON BLOOM SEQUENCE IN EUTROPHIED FRESHWATER PONDS

    EPA Science Inventory

    The extracellular metabolites of planktonic bloom dominant algae play a most significant role in the determination of bloom sequence in a eutrophied freshwater pond. Certain extracellular metabolites of planktonic blue-green algae substantially inhibit the growth of planktonic di...

  11. Discovering the secondary metabolite potential encoded within Entomopathogenic Fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article discusses the secondary metabolite potential of the insect pathogens Metarhizium and Beauveria, including a bioinformatics analysis of secondary metabolite genes for which no products are yet identified....

  12. Trends in DDT and pyrethroid resistance in Anopheles gambiae s.s. populations from urban and agro-industrial settings in southern Cameroon

    PubMed Central

    2009-01-01

    Background Pyrethroid insecticides are widely used for insect pest control in Cameroon. In certain insect species, particularly the malaria vector Anopheles gambiae, resistance to this class of insecticides is a source of great concern and needs to be monitored in order to sustain the efficacy of vector control operations in the fields. This study highlights trends in DDT and pyrethroid resistance in wild An. gambiae populations from South Cameroon. Methods Mosquitoes were collected between 2001 and 2007 in four sites in South Cameroon, where insecticides are used for agricultural or personal protection purposes. Insecticide use was documented in each site by interviewing residents. Batches of 2-4 days old adult female mosquitoes reared from larval collections were tested for susceptibility to DDT, permethrin and deltamethrin using standard WHO procedures. Control, dead and survivors mosquitoes from bioassays were identified by PCR-RFLP and characterized for the kdr mutations using either the AS-PCR or the HOLA method. Results Four chemical insecticide groups were cited in the study sites: organochlorines, organophosphates, carbamates and pyrethroids. These chemicals were used for personal, crop or wood protection. In the four An. gambiae populations tested, significant variation in resistance levels, molecular forms composition and kdr frequencies were recorded in the time span of the study. Increases in DDT and pyrethroid resistance, as observed in most areas, were generally associated with an increase in the relative frequency of the S molecular form carrying the kdr mutations at higher frequencies. In Mangoum, however, where only the S form was present, a significant increase in the frequency of kdr alleles between 2003 to 2007 diverged with a decrease of the level of resistance to DDT and pyrethroids. Analyses of the kdr frequencies in dead and surviving mosquitoes showed partial correlation between the kdr genotypes and resistance phenotypes, suggesting that

  13. DDT_dgarciah_3: Searching for complex fullerene-based molecules in the prototype fullerene Planetary Nebula IC 418

    NASA Astrophysics Data System (ADS)

    García-Hernández, D. A.

    2013-02-01

    The recent and unexpected detection of the most common fullerenes (C60 and C70) and proto-graphene in some Planetary Nebulae (PNe) raises the exciting possibility that other more complex fullerene-based molecules (e.g., carbon onions or multishell fullerenes, fullerene-adducts) might be ubiquitous in the Universe and continue to be serious candidates to explain many astrophysical phenomena. The presence of complex fullerene-based molecules such as carbon onions in the circumstellar shells of fullerene-containing PNe is strongly suggested by our recent analysis of the unusual diffuse interstellar bands detected towards two PNe where C60 had already been found. If complex fullerene-based molecules such as carbon onions are present in this peculiar class of stars, they could easily be detected in the far-IR range. Fullerene-containing PNe are usually very faint in the far-IR but our very recent detection of C60 fullerenes in PN IC 418 can now mitigate this unfortunate situation. Surprisingly, Herschel has not observed this very bright source - now considered the prototype fullerene-containing PN - as part of any approved program in previous cycles. Thus, a comprehensive far-IR study of the complex circumstellar environment where fullerenes and fullerene-based molecules may form is at present lacking. With this DDT proposal we aim at obtaining full range, high S/N, Herschel/PACS far-IR spectra of PN IC 418 to search for the spectral signatures of complex fullerene-based molecules such as multishell fullerenes (e.g., C60@C240, C240@C960), which are predicted to be detectable as relatively strong broad features in the far-IR range. If successful, these observations will constitute the first firm detection of the most complex molecules ever detected in space. In addition, we will search for the predicted hydrogenated amorphous carbon (HAC) associated feature at ~60 um to confirm/refute the HAC's processing/decomposition scenario as the preferred fullerene formation route

  14. Metabolite specific proton magnetic resonance imaging

    SciTech Connect

    Hurd, R.E.; Freeman, D.M.

    1989-06-01

    An imaging method is described that makes use of proton double quantum nuclear magnetic resonance (NMR) to construct images based on selected metabolites such as lactic acid. The optimization of the method is illustrated in vitro, followed by in vivo determination of lactic acid distribution in a solid tumor model. Water suppression and editing of lipid signals are such that two-dimensional spectra of lactic acid may be obtained from a radiation-induced fibrosarcoma (RIF-1) tumor in under 1 min and lactic acid images from the same tumor in under 1 hr at 2.0 T. This technique provides a fast and reproducible method at moderate magnetic field strength for mapping biologically relevant metabolites.

  15. Gut microbiota, metabolites and host immunity.

    PubMed

    Rooks, Michelle G; Garrett, Wendy S

    2016-05-27

    The microbiota - the collection of microorganisms that live within and on all mammals - provides crucial signals for the development and function of the immune system. Increased availability of technologies that profile microbial communities is facilitating the entry of many immunologists into the evolving field of host-microbiota studies. The microbial communities, their metabolites and components are not only necessary for immune homeostasis, they also influence the susceptibility of the host to many immune-mediated diseases and disorders. In this Review, we discuss technological and computational approaches for investigating the microbiome, as well as recent advances in our understanding of host immunity and microbial mutualism with a focus on specific microbial metabolites, bacterial components and the immune system. PMID:27231050

  16. Metabolites of a blocked chloramphenicol producer.

    PubMed

    Lewis, Elizabeth A; Adamek, Tamara L; Vining, Leo C; White, Robert L

    2003-01-01

    Addition of p-aminophenylalanine (4), an advanced biosynthetic precursor of the antibiotic chloramphenicol (5), to a Streptomyces venezuelae pabAB mutant (VS629) restored chloramphenicol production and led to formation of the non-chlorinated analogue corynecin II (6) and four acetanilide derivatives: p-(acetylamino)phenylalanine (7), p-(acetylamino)benzyl alcohol (13), p-(acetylamino)benzoic acid (14), and p-(acetylamino)phenol (acetaminophen, 16). Metabolite structures were deduced from NMR and MS-MS data and established by chromatographic and spectroscopic comparisons with authentic samples. Reference compound 13 was synthesized by reducing the acid chloride of 14. Shunt pathways are proposed to account for the formation of the metabolites from p-aminophenylalanine. PMID:12542347

  17. Emerging role of thyroid hormone metabolites.

    PubMed

    Gnocchi, D; Steffensen, K R; Bruscalupi, G; Parini, P

    2016-07-01

    Thyroid hormones (THs) are essential for the regulation of development and metabolism in key organs. THs produce biological effects both by directly affecting gene expression through the interaction with nuclear receptors (genomic effects) and by activating protein kinases and/or ion channels (short-term effects). Such activations can be either direct, in the case of ion channels, or mediated by membrane or cytoplasmic receptors. Short-term-activated signalling pathways often play a role in the regulation of genomic effects. Several TH intermediate metabolites, which were previously considered without biological activity, have now been associated with a broad range of actions, mostly attributable to short-term effects. Here, we give an overview of the physiological roles and mechanisms of action of THs, focusing on the emerging position that TH metabolites are acquiring as important regulators of physiology and metabolism. PMID:26748938

  18. Novel bioactive metabolites of dipyrone (metamizol).

    PubMed

    Rogosch, Tobias; Sinning, Christian; Podlewski, Agnes; Watzer, Bernhard; Schlosburg, Joel; Lichtman, Aron H; Cascio, Maria G; Bisogno, Tiziana; Di Marzo, Vincenzo; Nüsing, Rolf; Imming, Peter

    2012-01-01

    Dipyrone is a common antipyretic drug and the most popular non-opioid analgesic in many countries. In spite of its long and widespread use, molecular details of its fate in the body are not fully known. We administered dipyrone orally to mice. Two unknown metabolites were found, viz. the arachidonoyl amides of the known major dipyrone metabolites, 4-methylaminoantipyrine (2) and 4-aminoantipyrine (3). They were identified by ESI-LC-MS/MS after extraction from the CNS, and comparison with reference substances prepared synthetically. The arachidonoyl amides were positively tested for cannabis receptor binding (CB(1) and CB(2)) and cyclooxygenase inhibition (COX-1 and COX-2 in tissues and as isolated enzymes), suggesting that the endogenous cannabinoid system may play a role in the effects of dipyrone against pain. PMID:22172309

  19. Pryogalloloestrogens -- a new group of oestrogen metabolites.

    PubMed

    Stubenrauch, G; Gelbke, H P; Knuppen, R

    1976-01-01

    After incubation of radioactive catecholoestrogen monomethyl ethers with rat liver slices the following well known metabolic pathways were observed: 1) demethylation, 2) 16alpha-hydroxylation, 3) oxidoreduction at C-atom 17, and 4) conjugation with glutathione, sulphuric acid and glucuronic acid. In addition, for the first time a further aromatic ortho-hydroxylation, leading to pyrogalloloestrogen derivatives, was detected. Thus, the incubation of 2-methoxyoestrone yielded 2,4-dihydroxyoestrone 2-methyl ether as the main metabolite of the lipophile fraction. Under the same conditions, 4-methoxyoestrone was converted to 2,4-dihydroxyoestrone 4-methyl ether and 2,4-dihydroxyoestradiol-17beta 4-methyl ether; these compounds were the quantitatively most important metabolites not only in the lipophile but also in the sulphate and glucuronide fractions. The identity of these new metabolic products was established by chromatography, microchemical reactions and recrystallisation to constant specific radioactivity. PMID:1248801

  20. Biologically Active Metabolites Synthesized by Microalgae

    PubMed Central

    de Morais, Michele Greque; Vaz, Bruna da Silva; de Morais, Etiele Greque; Costa, Jorge Alberto Vieira

    2015-01-01

    Microalgae are microorganisms that have different morphological, physiological, and genetic traits that confer the ability to produce different biologically active metabolites. Microalgal biotechnology has become a subject of study for various fields, due to the varied bioproducts that can be obtained from these microorganisms. When microalgal cultivation processes are better understood, microalgae can become an environmentally friendly and economically viable source of compounds of interest, because production can be optimized in a controlled culture. The bioactive compounds derived from microalgae have anti-inflammatory, antimicrobial, and antioxidant activities, among others. Furthermore, these microorganisms have the ability to promote health and reduce the risk of the development of degenerative diseases. In this context, the aim of this review is to discuss bioactive metabolites produced by microalgae for possible applications in the life sciences. PMID:26339647

  1. [Basidiomycetes: A new source of secondary metabolites.].

    PubMed

    Brizuela, M A; García, L; Pérez, L; Mansur, M

    1998-06-01

    The area of natural products research is the most rapidly growing field of organic chemistry, due to the great technical developments in the isolation and identification techniques. Today, near to one million natural products -isolated from the most diverse living things- are known. Microorganisms are among the least-studied of these. Nevertheless, they offer large possibilities for the discovery of new structures and biological activities. Among the microorganisms, the Basidiomycetes present a production capacity and a range of biologically active metabolites, which have scarcely been investigated. The wide spectrum of natural products with biological activity produced by Basidiomycetes includes antimicrobial agents, antifungal, antiviral and cytotoxic activities, enzymes, plant growth regulators and flavors. These metabolites are generally grouped by their chemical origin, and the relationship between chemical structure and the different biological activities reported. The main objective of this review is to bring an updated revision of the numerous and interesting biosynthetic pathways from basidiomycetes. PMID:17655412

  2. Heterogeneous distribution of metabolites across plant species

    NASA Astrophysics Data System (ADS)

    Takemoto, Kazuhiro; Arita, Masanori

    2009-07-01

    We investigate the distribution of flavonoids, a major category of plant secondary metabolites, across species. Flavonoids are known to show high species specificity, and were once considered as chemical markers for understanding adaptive evolution and characterization of living organisms. We investigate the distribution among species using bipartite networks, and find that two heterogeneous distributions are conserved among several families: the power-law distributions of the number of flavonoids in a species and the number of shared species of a particular flavonoid. In order to explain the possible origin of the heterogeneity, we propose a simple model with, essentially, a single parameter. As a result, we show that two respective power-law statistics emerge from simple evolutionary mechanisms based on a multiplicative process. These findings provide insights into the evolution of metabolite diversity and characterization of living organisms that defy genome sequence analysis for different reasons.

  3. Preparative Microfluidic Electrosynthesis of Drug Metabolites

    PubMed Central

    2013-01-01

    In vivo, a drug molecule undergoes its first chemical transformation within the liver via CYP450-catalyzed oxidation. The chemical outcome of the first pass hepatic oxidation is key information to any drug development process. Electrochemistry can be used to simulate CYP450 oxidation, yet it is often confined to the analytical scale, hampering product isolation and full characterization. In an effort to replicate hepatic oxidations, while retaining high throughput at the preparative scale, microfluidic technology and electrochemistry are combined in this study by using a microfluidic electrochemical cell. Several commercial drugs were subjected to continuous-flow electrolysis. They were chosen for their various chemical reactivity: their metabolites in vivo are generated via aromatic hydroxylation, alkyl oxidation, glutathione conjugation, or sulfoxidation. It is demonstrated that such metabolites can be synthesized by flow electrolysis at the 10 to 100 mg scale, and the purified products are fully characterized. PMID:24900614

  4. Metabolic regulation and overproduction of primary metabolites

    PubMed Central

    Sanchez, Sergio; Demain, Arnold L.

    2008-01-01

    Summary Overproduction of microbial metabolites is related to developmental phases of microorganisms. Inducers, effectors, inhibitors and various signal molecules play a role in different types of overproduction. Biosynthesis of enzymes catalysing metabolic reactions in microbial cells is controlled by well‐known positive and negative mechanisms, e.g. induction, nutritional regulation (carbon or nitrogen source regulation), feedback regulation, etc. The microbial production of primary metabolites contributes significantly to the quality of life. Fermentative production of these compounds is still an important goal of modern biotechnology. Through fermentation, microorganisms growing on inexpensive carbon and nitrogen sources produce valuable products such as amino acids, nucleotides, organic acids and vitamins which can be added to food to enhance its flavour, or increase its nutritive values. The contribution of microorganisms goes well beyond the food and health industries with the renewed interest in solvent fermentations. Microorganisms have the potential to provide many petroleum‐derived products as well as the ethanol necessary for liquid fuel. Additional applications of primary metabolites lie in their impact as precursors of many pharmaceutical compounds. The roles of primary metabolites and the microbes which produce them will certainly increase in importance as time goes on. In the early years of fermentation processes, development of producing strains initially depended on classical strain breeding involving repeated random mutations, each followed by screening or selection. More recently, methods of molecular genetics have been used for the overproduction of primary metabolic products. The development of modern tools of molecular biology enabled more rational approaches for strain improvement. Techniques of transcriptome, proteome and metabolome analysis, as well as metabolic flux analysis. have recently been introduced in order to identify new and

  5. Three new metabolites from Botrytis cinerea.

    PubMed

    Wang, Tian-Shan; Zhou, Jin-Yan; Tan, Hong

    2008-01-01

    Three new metabolites, gamma-abscisolactone (1), botrytisic acids A (3) and B (4) were isolated from the fermentation broth of Botrytis cinerea TB-3-H8. Their structures were elucidated on the basis of MS, IR, UV, and NMR spectroscopic data. Compound 2 was isolated from natural resource for the first time. The structure of 1 was further confirmed by single-crystal X-ray diffraction (CCDC-265897). PMID:19003608

  6. Levels of DDT and PCB's in different stages of life cycle of the arctic tern Sterna paradisaea and the herring gull Larus argentatus

    SciTech Connect

    Lemmetyinen, R.; Rantamaki, P.; Karlin, A.

    1982-01-01

    ..sigma..DDT and PCB levels were analyzed in samples of arctic terns and herring gulls collected in the archipelago of southwestern Finland. Special attention was paid to the levels at various stages of the life cycle and in different sexes. The levels were nearly ten times higher in the herring gull. The highest loads were found in adult birds and in newly hatched chicks but the levels were much lower (only 7-12 % in the herring gull) in chicks just before fledgling. The levels in young gulls remained low until the end of August at least. Therefore it is plausible that the high levels found in adult gulls are a consequence of their wintering in the southern Baltic. The levels of ..sigma..DDT and PCB residues were significantly lower in female arctic terns than in male terns. Differences between the sexes were small in the herring gull. Thus it is possible that the female of the arctic tern is able to release pollutants, especially PCB residues, more effectively into eggs than the female of the herring gull. The biochemical mechanisms involved are not clear but a possible explanation may be different lipoprotein structures in the eggs of the species.

  7. Utilizing thin-film solid-phase extraction to assess the effect of organic carbon amendments on the bioavailability of DDT and dieldrin to earthworms.

    PubMed

    Andrade, Natasha A; Centofanti, Tiziana; McConnell, Laura L; Hapeman, Cathleen J; Torrents, Alba; Nguyen, Anh; Beyer, W Nelson; Chaney, Rufus L; Novak, Jeffrey M; Anderson, Marya O; Cantrell, Keri B

    2014-02-01

    Improved approaches are needed to assess bioavailability of hydrophobic organic compounds in contaminated soils. Performance of thin-film solid-phase extraction (TF-SPE) using vials coated with ethylene vinyl acetate was compared to earthworm bioassay (Lumbricus terrestris). A DDT and dieldrin contaminated soil was amended with four organic carbon materials to assess the change in bioavailability. Addition of organic carbon significantly lowered bioavailability for all compounds except for 4,4'-DDT. Equilibrium concentrations of compounds in the polymer were correlated with uptake by earthworms after 48d exposure (R(2) = 0.97; p < 0.001), indicating TF-SPE provided an accurate uptake simulation. Bioavailability of residues in soil was compared with a spiked soil aged for 90d in laboratory. Dieldrin and DDX were respectively 18% and 11% less bioavailable in contaminated soil relative to spiked soil despite >40yr of aging. Results show that TF-SPE can be useful in examining potential risks associated with contaminated soils and to test effectiveness of remediation efforts. PMID:24316068

  8. DDT and pyrethroid resistance status and laboratory evaluation of bio-efficacy of long lasting insecticide treated nets against Culex quinquefasciatus and Culex decens in Ghana.

    PubMed

    Kudom, Andreas A; Mensah, Ben A; Froeschl, Guenter; Rinder, Heinz; Boakye, Daniel

    2015-10-01

    Nuisance from Culex mosquitoes in Ghana has a serious negative impact on the standard of living in many urban communities. In addition, a perceived lack of efficacy of long lasting insecticide treated nets (LLINs) against nuisance mosquitoes contributes to their discontinued use. This again compromises malaria control, even if Anopheles species themselves would still be susceptible to the insecticides used. Control strategies involve pyrethroid insecticides but information on Culex mosquito susceptibility to these insecticides is limited. A nationwide survey was conducted to address this problem. In adults, susceptibility to permethrin, deltamethrin and DDT as well as enzyme activity and kdr mutation were determined. Cone and tunnel bioassay were also carried out to determine the efficacy of LLINs against the mosquitoes. Culex quinquefasciatus and Culex decens were identified in the study area. Higher deltamethrin and DDT resistance and relatively low permethrin resistance were observed in both species. High enzyme activities and kdr mutations were observed in C. quinquefasciatus but not in C. decens. However, reduced efficacy of LLINs was observed in both mosquito species. This adds up to the evidence of the spread of pyrethroid resistance in mosquitoes and its negative impact on control strategies. PMID:26215129

  9. Phthalate Metabolites, Consumer Habits and Health Effects.

    PubMed

    Wallner, Peter; Kundi, Michael; Hohenblum, Philipp; Scharf, Sigrid; Hutter, Hans-Peter

    2016-01-01

    Phthalates are multifunctional chemicals used in a wide variety of consumer products. The aim of this study was to investigate whether levels of urinary phthalate metabolites in urine samples of Austrian mothers and their children were associated with consumer habits and health indicators. Within an Austrian biomonitoring survey, urine samples from 50 mother-child pairs of five communities (two-stage random stratified sampling) were analysed. The concentrations of 14 phthalate metabolites were determined, and a questionnaire was administered. Monoethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), mono-isobutyl phthalate (MiBP), monobenzyl phthalate (MBzP), mono-(2-ethylhexyl) phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (5OH-MEHP), mono-(2-ethyl-5-oxohexyl) phthalate (5oxo-MEHP), mono-(5-carboxy-2-ethylpentyl) phthalate (5cx-MEPP), and 3-carboxy-mono-propyl phthalate (3cx-MPP) could be quantified in the majority of samples. Significant correlations were found between the use of hair mousse, hair dye, makeup, chewing gum, polyethylene terephthalate (PET) bottles and the diethyl phthalate (DEP) metabolite MEP. With regard to health effects, significant associations of MEP in urine with headache, repeated coughing, diarrhoea, and hormonal problems were observed. MBzP was associated with repeated coughing and MEHP was associated with itching. PMID:27428989

  10. Phthalate Metabolites, Consumer Habits and Health Effects

    PubMed Central

    Wallner, Peter; Kundi, Michael; Hohenblum, Philipp; Scharf, Sigrid; Hutter, Hans-Peter

    2016-01-01

    Phthalates are multifunctional chemicals used in a wide variety of consumer products. The aim of this study was to investigate whether levels of urinary phthalate metabolites in urine samples of Austrian mothers and their children were associated with consumer habits and health indicators. Within an Austrian biomonitoring survey, urine samples from 50 mother-child pairs of five communities (two-stage random stratified sampling) were analysed. The concentrations of 14 phthalate metabolites were determined, and a questionnaire was administered. Monoethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), mono-isobutyl phthalate (MiBP), monobenzyl phthalate (MBzP), mono-(2-ethylhexyl) phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (5OH-MEHP), mono-(2-ethyl-5-oxohexyl) phthalate (5oxo-MEHP), mono-(5-carboxy-2-ethylpentyl) phthalate (5cx-MEPP), and 3-carboxy-mono-propyl phthalate (3cx-MPP) could be quantified in the majority of samples. Significant correlations were found between the use of hair mousse, hair dye, makeup, chewing gum, polyethylene terephthalate (PET) bottles and the diethyl phthalate (DEP) metabolite MEP. With regard to health effects, significant associations of MEP in urine with headache, repeated coughing, diarrhoea, and hormonal problems were observed. MBzP was associated with repeated coughing and MEHP was associated with itching. PMID:27428989

  11. The WEIZMASS spectral library for high-confidence metabolite identification.

    PubMed

    Shahaf, Nir; Rogachev, Ilana; Heinig, Uwe; Meir, Sagit; Malitsky, Sergey; Battat, Maor; Wyner, Hilary; Zheng, Shuning; Wehrens, Ron; Aharoni, Asaph

    2016-01-01

    Annotation of metabolites is an essential, yet problematic, aspect of mass spectrometry (MS)-based metabolomics assays. The current repertoire of definitive annotations of metabolite spectra in public MS databases is limited and suffers from lack of chemical and taxonomic diversity. Furthermore, the heterogeneity of the data prevents the development of universally applicable metabolite annotation tools. Here we present a combined experimental and computational platform to advance this key issue in metabolomics. WEIZMASS is a unique reference metabolite spectral library developed from high-resolution MS data acquired from a structurally diverse set of 3,540 plant metabolites. We also present MatchWeiz, a multi-module strategy using a probabilistic approach to match library and experimental data. This strategy allows efficient and high-confidence identification of dozens of metabolites in model and exotic plants, including metabolites not previously reported in plants or found in few plant species to date. PMID:27571918

  12. Detection and characterization of clostebol sulfate metabolites in Caucasian population.

    PubMed

    Balcells, Georgina; Pozo, Oscar J; Garrostas, Lorena; Esquivel, Argitxu; Matabosch, Xavier; Kotronoulas, Aristotelis; Joglar, Jesús; Ventura, Rosa

    2016-06-01

    Anabolic androgenic steroids (AAS) are synthetic testosterone derivatives which undergo extensive metabolism in man. Differences in the excretion of phase II metabolites are strongly associated with inter-individual and inter-ethnic variations. Sulfate metabolites have been described as long-term metabolites for some AAS. Clostebol is the 4-chloro derivative of testosterone and the aim of the present study was the evaluation of clostebol sulfate metabolites in Caucasian population by LC-MS/MS technology. Clostebol was orally administered to four healthy Caucasian male volunteers, and excretion study urines were collected up to 31 days. Several analytical strategies (neutral loss scan, precursor ion scan and selected reaction monitoring acquisitions modes) were applied to detect sulfate metabolites in post-administration samples. Sixteen sulfate metabolites were detected, five of them having detectability times above 10 days (S1a, S2a, S3b, S3g and S4b). Interestingly, metabolite S1a could be detected up to the last collected sample of all excretion studies and it was characterized by LC-MS/MS and GC-MS as 4ξ-chloro-5α-androst-3β-ol-17-one 3β-sulfate. Thus, monitoring of S1a improves the detection time of clostebol misuse with respect to the commonly monitored metabolites, excreted in the glucuronide fraction. Importantly, this new metabolite can be incorporated into recently developed LC-MS/MS screening methods base on the direct detection of phase II metabolites. PMID:27085012

  13. Maternal and Infant Urinary Phthalate Metabolite Concentrations: Are They Related?

    PubMed Central

    Sathyanarayana, S; Calafat, Antonia Maria; Liu, Fan; Swan, Shanna Helen

    2008-01-01

    Background Phthalates are synthetic chemicals that are ubiquitous in our society and may have adverse health effects in humans. Detectable concentrations of phthalate metabolites have been found in adults and children, but no studies have examined the relationship between maternal and infant phthalate metabolite concentrations. Objective We investigated the relationship between maternal and infant urinary phthalate metabolite concentrations. Methods We measured nine phthalate metabolites in urine samples from 210 mother/infant pairs collected on the same study visit day (1999–2005) and obtained demographic history from questionnaires. Using multivariate linear regression analyses, we examined the degree to which maternal urine phthalate metabolite concentration predicted infant phthalate metabolite concentration. All analyses were adjusted for infant age, creatinine concentration, and race. Results Correlation coefficients between phthalate metabolite concentrations in the urine of mothers and their infants were generally low but increased with decreasing age of infant. In multivariate analyses, mother’s phthalate metabolite concentrations were significantly associated with infants’ concentrations for six phthalate metabolites: monobenzyl phthalate, monoethyl phthalate, monoisobutyl phthalate, and three metabolites of di(2-ethylhexyl) phthalate: mono(2-ethylhexyl) phthalate, mono(2-ethyl-5-hydroxy-hexyl) phthalate and mono(2-ethyl-5-oxo-hexyl) phthalate (p-values for all coefficients <0.05). Discussion Mother’s urine phthalate metabolite concentration is significantly associated with infant urine phthalate metabolite concentration for six phthalate metabolites. It is plausible that shared exposures to phthalates in the immediate surrounding environment accounted for these relationships, but other unidentified sources may also contribute to infants’ phthalate exposures. This study indicates the importance of further identifying infant phthalate exposures

  14. Endogenous cross-talk of fungal metabolites

    PubMed Central

    Sheridan, Kevin J.; Dolan, Stephen K.; Doyle, Sean

    2015-01-01

    Non-ribosomal peptide (NRP) synthesis in fungi requires a ready supply of proteogenic and non-proteogenic amino acids which are subsequently incorporated into the nascent NRP via a thiotemplate mechanism catalyzed by NRP synthetases. Substrate amino acids can be modified prior to or during incorporation into the NRP, or following incorporation into an early stage amino acid-containing biosynthetic intermediate. These post-incorporation modifications involve a range of additional enzymatic activities including but not exclusively, monooxygenases, methyltransferases, epimerases, oxidoreductases, and glutathione S-transferases which are essential to effect biosynthesis of the final NRP. Likewise, polyketide biosynthesis is directly by polyketide synthase megaenzymes and cluster-encoded ancillary decorating enzymes. Additionally, a suite of additional primary metabolites, for example: coenzyme A (CoA), acetyl CoA, S-adenosylmethionine, glutathione (GSH), NADPH, malonyl CoA, and molecular oxygen, amongst others are required for NRP and polyketide synthesis (PKS). Clearly these processes must involve exquisite orchestration to facilitate the simultaneous biosynthesis of different types of NRPs, polyketides, and related metabolites requiring identical or similar biosynthetic precursors or co-factors. Moreover, the near identical structures of many natural products within a given family (e.g., ergot alkaloids), along with localization to similar regions within fungi (e.g., conidia) suggests that cross-talk may exist, in terms of biosynthesis and functionality. Finally, we speculate if certain biosynthetic steps involved in NRP and PKS play a role in cellular protection or environmental adaptation, and wonder if these enzymatic reactions are of equivalent importance to the actual biosynthesis of the final metabolite. PMID:25601857

  15. Resistance to DDT and Pyrethroids and Increased kdr Mutation Frequency in An. gambiae after the Implementation of Permethrin-Treated Nets in Senegal

    PubMed Central

    Ndiath, Mamadou O.; Sougoufara, Seynabou; Gaye, Abdoulaye; Mazenot, Catherine; Konate, Lassana; Faye, Oumar; Sokhna, Cheikh; Trape, Jean-Francois

    2012-01-01

    Introduction The aim of this study was to evaluate the susceptibility to insecticides of An. gambiae mosquitoes sampled in Dielmo (Senegal), in 2010, 2 years after the implementation of Long Lasting Insecticide-treated Nets (LLINs) and to report the evolution of kdr mutation frequency from 2006 to 2010. Methods WHO bioassay susceptibility tests to 6 insecticides were performed on adults F0, issuing from immature stages of An. gambiae s.l., sampled in August 2010. Species and molecular forms as well as the presence of L1014F and L1014S kdr mutations were assessed by PCR. Longitudinal study of kdr mutations was performed on adult mosquitoes sampled monthly by night landing catches from 2006 to 2010. Findings No specimen studied presented the L1014S mutation. During the longitudinal study, L1014F allelic frequency rose from 2.4% in year before the implementation of LLINs to 4.6% 0–12 months after and 18.7% 13–30 months after. In 2010, An. gambiae were resistant to DDT, Lambda-cyhalothrin, Deltamethrin and Permethrin (mortality rates ranging from 46 to 63%) but highly susceptible to Fenitrothion and Bendiocarb (100% mortality). There was significantly more RR genotype among An. gambiae surviving exposure to DDT or Pyrethroids. An. arabiensis represented 3.7% of the sampled mosquitoes (11/300) with no kdr resistance allele detected. An. gambiae molecular form M represented 29.7% of the mosquitoes with, among them, kdr genotypes SR (18%) and SS (82%). An. gambiae molecular form S represented 66% of the population with, among them, kdr genotype SS (33.3%), SR (55.6%) and RR (11.1%). Only 2 MS hybrid mosquitoes were sampled and presented SS kdr genotype. Conclusion Biological evidence of resistance to DDT and pyrethroids was detected among An. gambiae mosquitoes in Dielmo (Senegal) within 24 months of community use of LLINs. Molecular identification of L1014F mutation indicated that target site resistance increased after the implementation of LLINs. PMID:22384107

  16. [Pyrethroid and DDT resistance of Anopheles gambiae s.s. (Diptera: Culicidae) in five agricultural ecosystems from Côte-d'Ivoire].

    PubMed

    Tia, E; Akogbeto, M; Koffi, A; Toure, M; Adja, A M; Moussa, K; Yao, T; Carnevale, P; Chandre, E

    2006-10-01

    The promotion of pyrethroid impregnated bednets among the populations is a major activity of the National Malaria Vector Control Programs in African tropical countries. However pyrethroid resistance in Anopheles gambiae, a major malaria vector, has been observed in several parts of Côte-d'Ivoire since 1993. As insecticides used in agriculture against pests are frequently considered as important factors responsible for resistance in malaria vectors, we have evaluated insecticide resistance of An. gambiae populations taking into account the main crops cultivated in Côte-d'Ivoire. Five areas were selected according to the use of insecticide either in agriculture or for domestic purposes: a urban area where vegetables and rice are main crops, a rural rice growing area, a rural area of coffee/cocoa production, a rural area of fruit farming and a rural area without any use of agricultural insecticide. Susceptibility tests were carried out using WHO diagnostic test kits. About 6500 females of An. gambiae were exposed to insecticide impregnated papers (permethrin 1%, deltamethrin 0.05%, DDT 4%) for one hour. Results confirmed that both mortality rates and knockdown time analysis were important to study the resistance data. By using mortality rates, populations of An. gambiae were found to be resistant to pyrethroids and DDT in four of the five areas. Resistance was the highest in urban area, lower in fruit and coffee/cocoa areas and at low level in rice growing area. An. gambiae from area without agricultural treatment was found susceptible to pyrethroids but slightly resistant to DDT A significant increase of knockdown time was observed in all areas with the 3 insecticides. These results agreed with previous studies showing that kdr mutation was the main resistance mechanism to pyrethroids in An. gambiae populations in Côte-d'Ivoire. They also agreed with knockdown time which is an early indicator of resistance development for the population in area without

  17. Cytochrome c adducts with PCB quinoid metabolites.

    PubMed

    Li, Miao; Teesch, Lynn M; Murry, Daryl J; Pope, R Marshal; Li, Yalan; Robertson, Larry W; Ludewig, Gabriele

    2016-02-01

    Polychlorinated biphenyls (PCBs) are a group of 209 individual congeners widely used as industrial chemicals. PCBs are found as by-products in dye and paint manufacture and are legacy, ubiquitous, and persistent as human and environmental contaminants. PCBs with fewer chlorine atoms may be metabolized to hydroxy- and dihydroxy-metabolites and further oxidized to quinoid metabolites both in vitro and in vivo. Specifically, quinoid metabolites may form adducts on nucleophilic sites within cells. We hypothesized that the PCB-quinones covalently bind to cytochrome c and, thereby, cause defects in the function of cytochrome c. In this study, synthetic PCB quinones, 2-(4'-chlorophenyl)-1,4-benzoquinone (PCB3-pQ), 4-4'-chlorophenyl)-1,2-benzoquinone (PCB3-oQ), 2-(3', 5'-dichlorophenyl)-1,4-benzoquinone, 2-(3',4', 5'-trichlorophenyl)-1,4-benzoquinone, and 2-(4'-chlorophenyl)-3,6-dichloro-1,4-benzoquinone, were incubated with cytochrome c, and adducts were detected by liquid chromatography-mass spectrometry (LC-MS) and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI TOF). Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was employed to separate the adducted proteins, while trypsin digestion and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were applied to identify the amino acid binding sites on cytochrome c. Conformation change of cytochrome c after binding with PCB3-pQ was investigated by SYBYL-X simulation and cytochrome c function was examined. We found that more than one molecule of PCB-quinone may bind to one molecule of cytochrome c. Lysine and glutamic acid were identified as the predominant binding sites. Software simulation showed conformation changes of adducted cytochrome c. Additionally, cross-linking of cytochrome c was observed on the SDS-PAGE gel. Cytochrome c was found to lose its function as electron acceptor after incubation with PCB quinones. These data provide evidence that the covalent

  18. Antimycobacterial activity of lichen metabolites in vitro.

    PubMed

    Ingólfsdóttir, K; Chung, G A; Skúlason, V G; Gissurarson, S R; Vilhelmsdóttir, M

    1998-04-01

    Several compounds, whose structures represent the most common chemical classes of lichen metabolites, were screened for in vitro activity against Mycobacterium aurum, a non-pathogenic organism with a similar sensitivity profile to M. tuberculosis. Of the compounds tested, usnic acid from Cladonia arbuscula exhibited the highest activity with an MIC value of 32 microg/ml. Atranorin and lobaric acid, both isolated from Stereocaulon alpinum, salazinic acid from Parmelia saxatilis and protolichesterinic acid from Cetraria islandica all showed MIC values >/=125 microg/ml. PMID:9795033

  19. MASS SPECTROMETRY IMAGING FOR DRUGS AND METABOLITES

    PubMed Central

    Greer, Tyler; Sturm, Robert; Li, Lingjun

    2011-01-01

    Mass spectrometric imaging (MSI) is a powerful analytical technique that provides two- and three-dimensional spatial maps of multiple compounds in a single experiment. This technique has been routinely applied to protein, peptide, and lipid molecules with much less research reporting small molecule distributions, especially pharmaceutical drugs. This review’s main focus is to provide readers with an up-to-date description of the substrates and compounds that have been analyzed for drug and metabolite composition using MSI technology. Additionally, ionization techniques, sample preparation, and instrumentation developments are discussed. PMID:21515430

  20. METABOLIC INTERACTIONS OF HORMONAL STEROIDS AND CHLORINATED HYDROCARBONS: EFFECTS OF NEONATAL TREATMENT WITH O,P'-DDT ON THE DEVELOPMENT OF THE STEROIDOGENIC ENDOCRINE SYSTEM OF THE MALE RAT

    EPA Science Inventory

    The study generated approaches to the measurements of the potential of xenobiotics to alter reproductive capacity and viability which may allow improvement of those currently in use. More specifically, it identified the effects of neonatal exposure to the model compound, o,p'-DDT...

  1. EFFECT OF 17B-ESTRADIOL, O,P'-DDT, OCTYLPHENOL AND P,P'-DDE ON GONADAL DEVELOPMENT AND LIVER AND KIDNEY PATHOLOGY IN JUVENILE MALE SUMMER FLOUNDER (PARALICHTYS DENTATUS)

    EPA Science Inventory

    The intent of this study was to compare histopathologically the effect of 17 -estradiol (E2), o,p' DDT, octylphenol and p,p' DDE on gonadal development and liver and kidney condition in sexually immature (juvenile) summer flounder (Paralichthys dentatus). The dorsal sinus of 2-...

  2. Effects of amendments on soil availability and phytoremediation potential of aged p,p'-DDT, p,p'-DDE and p,p'-DDD residues by willow plants (Salix sp.).

    PubMed

    Mitton, Francesca M; Gonzalez, Mariana; Peña, Aránzazu; Miglioranza, Karina S B

    2012-02-15

    Combining technologies offer a great potential to phytoremediate contaminated soils. As sequestration occurs, pollutants availability decline and organic amendments could counterbalance that situation. This work studies the potential of willow plants to phytoremediate soil containing p,p'-DDT (101.3 ng g(-1)) and p,p'-DDE (381.4 ng g(-1)) residues. The effect of root exudates, Tween 80 and citric and oxalic acids on DDTs desorption and availability from soil was tested together with the plant uptake and translocation. Treatments increased the p,p'-DDE/p,p'-DDT ratio when compared with control (water) soil. Watering with carboxylic acids led to a significant enhancement of the quantities of p,p'-DDT and p,p'-DDE desorbed from soil that was related with an increase of organic carbon in solution. Willow plants accumulated DDTs under all treatments although plants watered with carboxylic acids showed the highest leaves translocation factor for both p,p'-DDT and p,p'-DDE. Results indicate that the addition of carboxylic acids enhanced DDTs bioavailability which further increases plant uptake and translocation. The effect of surfactants on the soil-plant systems needs to be better assessed for this particular soil and plant species. The enhancement of soluble organic carbon is crucial at the moment of evaluating DDTs release from soil as well as to establish cleaning strategies. PMID:22188788

  3. Novel sulfur-containing microbial metabolite of primaquine.

    PubMed

    Hufford, C D; Baker, J K; McChesney, J D; Clark, A M

    1986-08-01

    Microbial metabolism studies of the antimalarial drug primaquine, using Streptomyces roseochromogenus (ATCC 13400) have produced an N-acetylated metabolite and a methylene-linked dimeric product, both of which have been previously reported, and a novel sulfur-containing microbial metabolite. The structure of the metabolite as a sulfur-linked dimer was proposed on the basis of spectral and chemical data. The molecular formula C34H44N6O4S was established from field-desorption mass spectroscopy and analytical data. The 1H- and 13C-nuclear magnetic resonance spectral data firmly established that the novel metabolite was a symmetrically substituted dimer of primaquine N-acetate with a sulfur atom linking the two units at C-5. The metabolite has been shown to be a mixture of stereoisomers which can equilibrate in solution. This observation was confirmed by microbial synthesis of the metabolite from optically active primaquine. PMID:3767340

  4. Herbicide Metabolites in Surface Water and Groundwater: Introduction and Overview

    USGS Publications Warehouse

    Thurman, E.M.; Meyer, M.T.

    1996-01-01

    Several future research topics for herbicide metabolites in surface and ground water are outlined in this chapter. They are herbicide usage, chemical analysis of metabolites, and fate and transport of metabolites in surface and ground water. These three ideas follow the themes in this book, which are the summary of a symposium of the American Chemical Society on herbicide metabolites in surface and ground water. First, geographic information systems allow the spatial distribution of herbicide-use data to be combined with geochemical information on fate and transport of herbicides. Next these two types of information are useful in predicting the kinds of metabolites present and their probable distribution in surface and ground water. Finally, methods development efforts may be focused on these specific target analytes. This chapter discusses these three concepts and provides an introduction to this book on the analysis, chemistry, and fate and transport of herbicide metabolites in surface and ground water.

  5. Using Hairy Roots for Production of Valuable Plant Secondary Metabolites.

    PubMed

    Tian, Li

    2015-01-01

    Plants synthesize a wide variety of natural products, which are traditionally termed secondary metabolites and, more recently, coined specialized metabolites. While these chemical compounds are employed by plants for interactions with their environment, humans have long since explored and exploited plant secondary metabolites for medicinal and practical uses. Due to the tissue-specific and low-abundance accumulation of these metabolites, alternative means of production in systems other than intact plants are sought after. To this end, hairy root culture presents an excellent platform for producing valuable secondary metabolites. This chapter will focus on several major groups of secondary metabolites that are manufactured by hairy roots established from different plant species. Additionally, the methods for preservations of hairy roots will also be reviewed. PMID:25583225

  6. Evaluation of the efficacy of DDT indoor residual spraying and long-lasting insecticidal nets against insecticide resistant populations of Anopheles arabiensis Patton (Diptera: Culicidae) from Ethiopia using experimental huts

    PubMed Central

    2014-01-01

    Background Indoor Residual Spraying (IRS) and Long-Lasting Insecticidal nets (LLINs) are major malaria vector control tools in Ethiopia. However, recent reports from different parts of the country showed that populations of Anopheles arabiensis, the principal malaria vector, have developed resistance to most families of insecticides recommended for public health use which may compromise the efficacy of both of these key vector control interventions. Thus, this study evaluated the efficacy of DDT IRS and LLINs against resistant populations of An. arabiensis using experimental huts in Asendabo area, southwestern Ethiopia. Methods The susceptibility status of populations of An. arabiensis was assessed using WHO test kits to DDT, deltamethrin, malathion, lambda-cyhalothrin, fenitrothion and bendiocarb. The efficacy of LLIN (PermaNet® 2.0), was evaluated using the WHO cone bioassay. Moreover, the effect of the observed resistance against malaria vector control interventions (DDT IRS and LLINs) were assessed using experimental huts. Results The findings of this study revealed that populations of An. arabiensis were resistant to DDT, deltamethrin, lambda-cyhalothrin and malathion with mortality rates of 1.3%, 18.8%, 36.3% and 72.5%, respectively but susceptible to fenitrothion and bendiocarb with mortality rates of 98.81% and 97.5%, respectively. The bio-efficacy test of LLIN (PermaNet® 2.0) against An. arabiensis revealed that the mosquito population showed moderate knockdown (64%) and mortality (78%). Moreover, mosquito mortalities in DDT sprayed huts and in huts with LLINs were not significantly different (p > 0.05) from their respective controls. Conclusion The evaluation of the efficacy of DDT IRS and LLINs using experimental huts showed that both vector control tools had only low to moderate efficacy against An. arabiensis populations from Ethiopia. Despite DDT being replaced by carbamates for IRS, the low efficacy of LLINs against the resistant population of An

  7. Effects of the environmental estrogens bisphenol A, o,p'-DDT, p-tert-octylphenol and coumestrol on apoptosis induction, cell proliferation and the expression of estrogen sensitive molecular parameters in the human breast cancer cell line MCF-7.

    PubMed

    Diel, Patrick; Olff, Sabine; Schmidt, Simone; Michna, Horst

    2002-01-01

    In the presented study, we have analysed effects of the environmental estrogens bisphenol A (BPA), p-tert-octylphenol (OCT), o,p'-DDT (DDT) and coumestrol (COU) on cell proliferation, apoptosis induction, progesterone receptor (PR) and androgen receptor (AR) mRNA expression and ER alpha protein expression in comparison to estradiol (E2) and the selective ER modulator (SERM) raloxifene (RAL) and the pure antiestrogen faslodex (ICI 182780) in the human breast cancer cell line MCF-7. A dose dependent analysis of the cell cycle distribution of MCF-7 cells after administration of OCT, DDT and COU revealed a significant induction of cell proliferation and reduced rate of apoptosis. Maximum induction of cell proliferation and the lowest rate of apoptosis could be observed at a dose of 10(-6)M. Interestingly, administration of BPA reduces the rate of apoptosis, but does not enhance proliferation at any dose analysed. PR mRNA expression in MCF-7 cells was up regulated after administration of COU and DDT, whereas treatment with BPA and OCT did not effect PR mRNA expression. AR mRNA expression was down regulated by COU, but not effected by BPA, DDT and OCT. The expression of ER alpha protein in the breast cancer cells was slightly down regulated by COU and DDT, but unaffected by BPA and OCT. In summary and in comparison to the effects observed after administration of E2, RAL and ICI our data indicate that none of the analysed compounds exhibit properties comparable to RAL and ICI. COU and DDT exhibit properties which are very similar to E2. Administration of BPA and OCT did not effect any of the estrogen sensitive molecular parameters analysed. Nevertheless OCT is a very potent stimulator of cell proliferation in MCF-7 cells. Surprisingly, BPA is not able to induce the proliferation of MCF-7 breast cancer cells, but turns out to be a very potent inhibitor of apoptosis. For this reason and in agreement to the effects of BPA on the molecular parameters analysed, we conclude

  8. Metabolite profiling of wheat (Triticum aestivum L.) phloem exudate

    PubMed Central

    2014-01-01

    Background Biofortification of staple crops with essential micronutrients relies on the efficient, long distance transport of nutrients to the developing seed. The main route of this transport in common wheat (Triticum aestivum) is via the phloem, but due to the reactive nature of some essential micronutrients (specifically Fe and Zn), they need to form ligands with metabolites for transport within the phloem. Current methods available in collecting phloem exudate allows for small volumes (μL or nL) to be collected which limits the breadth of metabolite analysis. We present a technical advance in the measurement of 79 metabolites in as little as 19.5 nL of phloem exudate. This was achieved by using mass spectrometry based, metabolomic techniques. Results Using gas chromatography–mass spectrometry (GC-MS), 79 metabolites were detected in wheat phloem. Of these, 53 were identified with respect to their chemistry and 26 were classified as unknowns. Using the ratio of ion area for each metabolite to the total ion area for all metabolites, 39 showed significant changes in metabolite profile with a change in wheat reproductive maturity, from 8–12 to 17–21 days after anthesis. Of these, 21 were shown to increase and 18 decreased as the plant matured. An amine group derivitisation method coupled with liquid chromatography MS (LC-MS) based metabolomics was able to quantify 26 metabolites and semi-quantitative data was available for a further 3 metabolites. Conclusions This study demonstrates that it is possible to determine metabolite profiles from extremely small volumes of phloem exudate and that this method can be used to determine variability within the metabolite profile of phloem that has occurred with changes in maturity. This is also believed to be the first report of the presence of the important metal complexing metabolite, nicotianamine in the phloem of wheat. PMID:25143779

  9. Cyanobacteria as Cell Factories to Produce Plant Secondary Metabolites

    PubMed Central

    Xue, Yong; He, Qingfang

    2015-01-01

    Cyanobacteria represent a promising platform for the production of plant secondary metabolites. Their capacity to express plant P450 proteins, which have essential functions in the biosynthesis of many plant secondary metabolites, makes cyanobacteria ideal for this purpose, and their photosynthetic capability allows cyanobacteria to grow with simple nutrient inputs. This review summarizes the advantages of using cyanobacteria to transgenically produce plant secondary metabolites. Some techniques to improve heterologous gene expression in cyanobacteria are discussed. PMID:25973419

  10. Structure elucidation of metabolites of swertiamarin produced by Aspergillus niger

    NASA Astrophysics Data System (ADS)

    Jun, Chang; Xue-Ming, Zhao; Chang-Xiao, Liu; Tie-Jun, Zhang

    2008-04-01

    The in vitro metabolism of swertiamarin was carried out in preparative scale using the fungus Aspergillus niger and the metabolites were isolated by semi-preparative HPLC combined with liquid-liquid extraction. Two metabolites, erythrocentaurin and one new compound were obtained and identified by 1H, 13C and 2D NMR and high resolution MS. The anti-inflammatory activity of the novel metabolite was tested and compared with that of swertiamarin in a mice model.

  11. Hormonal and Metabolite Regulation of Hepatic Glucokinase.

    PubMed

    Agius, Loranne

    2016-07-17

    Liver glucose metabolism is dependent on glucokinase activity. Glucokinase expression is transcriptionally regulated by hormones and metabolites of glucose, and glucokinase activity is dependent on reversible binding of glucokinase to a specific inhibitor protein, glucokinase regulatory protein (GKRP), and to other binding proteins such as 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase (PFK2/FBP2), which functions as an activator. Glucokinase is inhibited in the postabsorptive state by sequestration in the nucleus bound to GKRP, and it is activated postprandially by portal hyperglycemia and fructose through dissociation from GKRP, translocation to the cytoplasm, and binding to PFK2/FBP2. Glucagon dissociates this interaction, promoting translocation back to the nucleus. In humans, changes in glucokinase expression and activity are associated with poorly controlled type 2 diabetes and with nonalcoholic fatty liver disease, and a common variant of GKRP with altered binding affinity for glucokinase is associated with increased blood and liver lipids and other metabolic traits that implicate a role for GKRP in maintaining intrahepatic metabolite homeostasis. PMID:27146014

  12. Buckwheat phenolic metabolites in health and disease.

    PubMed

    Kreft, Marko

    2016-06-01

    Buckwheat (Fagopyrum esculentum Moench, F. tataricum Gaertner) groats and flour have been established globally as nutritional foods because of their high levels of proteins, polyphenols and minerals. In some regions, buckwheat herb is used as a functional food. In the present study, reports of in vitro studies, preclinical and clinical trials dealing with the effect of buckwheat and its metabolites were reviewed. There are numerous reports of potential health benefits of consuming buckwheat, which may be in the form of food, dietary supplements, home remedies or possibly pharmaceutical drugs; however, adverse effects, including those resulting from contamination, must be considered. There are reports of antioxidative activity of buckwheat, which contains high levels of rutin and quercetin. On the other hand, both cytotoxic and antigenotoxic effects have been shown. Reduction of hyperlipidaemia, reduction of blood pressure and improved weight regulation have been suggested. Consuming buckwheat may have a beneficial effect on diabetes, since lower postprandial blood glucose and insulin response have been reported. In addition, buckwheat metabolites, such as rutin, may have intrinsic protective effects in preserving insulin signalling. Rutin has also been suggested to have potential therapeutic applications for the treatment of Alzheimer's disease. The literature indicates that buckwheat is safe to consume and may have various beneficial effects on human health. PMID:27046048

  13. Metabolite production by different Ulocladium species.

    PubMed

    Andersen, Birgitte; Hollensted, Morten

    2008-08-15

    Ulocladium, which is phylogenetically related to Alternaria, contains species that are food spoilers and plant pathogens, but also species that have potential as enzyme producers and bio-control agents. Ulocladium spp. are often found on dead vegetation, in soil, air and dust, but also on food and feedstuffs and on water-damaged building materials. The aim was to study the morphological and chemical diversity within the genus Ulocladium. Cultures of 52 Ulocladium strains were identified morphologically, and then extracted and analyzed using automated Chemical Image Analysis. Production of individual metabolites was correlated to species identity and source of isolation (substratum). Chemical analyses corroborated the morphological identifications and showed the existence of several species species-specific metabolites, of which most were known compounds. The production of curvularins was specific to Ulocladium atrum, while most species produced infectopyrones and derivatives of altertoxin I. None of the 52 Ulocladium strains produced alternariols, tenuazonic acid, altersolanols or macrosporin, which are common in species of Alternaria. PMID:18599140

  14. Antiinflammatory and Immunomodulating Properties of Fungal Metabolites

    PubMed Central

    Lull, Cristina; Wichers, Harry J.; Savelkoul, Huub F. J.

    2005-01-01

    We discuss current information on the ability of extracts and isolated metabolites from mushrooms to modulate immune responses. This can result in a more enhanced innate and acquired disease resistance. The major immunomodulating effects of these active substances derived from mushrooms include mitogenicity and activation of immune effector cells, such as lymphocytes, macrophages, and natural killer cells, resulting in the production of cytokines, including interleukins (ILs), tumor necrosis factor alpha (TNF)-α, and interferon gamma (INF)-γ. In particular, the ability of selective mushroom extracts to modulate the differentiation capacity of CD4+ T cells to mature into TH1 and/or TH2 subsets will be discussed. As a consequence these extracts will have profound effects in particular diseases, like chronic autoimmune TH1-mediated or allergic TH2-mediated diseases. Immunosuppressive effects by mushroom components have also been observed. The therapeutic effects of mushrooms, such as anticancer activity, suppression of autoimmune diseases, and allergy have been associated with their immunomodulating effects. However, further studies are needed to determine the molecular mechanisms of the immunomodulating effects of mushrooms metabolites both individually and in complex mixtures, for example, extracts. PMID:16030389

  15. Multiple tyrosine metabolites are GPR35 agonists

    PubMed Central

    Deng, Huayun; Hu, Haibei; Fang, Ye

    2012-01-01

    Both kynurenic acid and 2-acyl lysophosphatidic acid have been postulated to be the endogenous agonists of GPR35. However, controversy remains whether alternative endogenous agonists exist. The molecular targets accounted for many nongenomic actions of thyroid hormones are mostly unknown. Here we report the agonist activity of multiple tyrosine metabolites at the GPR35. Tyrosine metabolism intermediates that contain carboxylic acid and/or catechol functional groups were first selected. Whole cell dynamic mass redistribution (DMR) assays enabled by label-free optical biosensor were then used to characterize their agonist activity in native HT-29. Molecular assays including β-arrestin translocation, ERK phosphorylation and receptor internalization confirmed that GPR35 functions as a receptor for 5,6-dihydroxyindole-2-carboxylic acid, 3,3′,5′-triiodothyronine, 3,3′,5-triiodothyronine, gentisate, rosmarinate, and 3-nitrotyrosine. These results suggest that multiple tyrosine metabolites are alternative endogenous ligands of GPR35, and GPR35 may represent a druggable target for treating certain diseases associated with abnormality of tyrosine metabolism. PMID:22523636

  16. Cholesterol metabolites exported from human brain.

    PubMed

    Iuliano, Luigi; Crick, Peter J; Zerbinati, Chiara; Tritapepe, Luigi; Abdel-Khalik, Jonas; Poirot, Marc; Wang, Yuqin; Griffiths, William J

    2015-07-01

    The human brain contains approximately 25% of the body's cholesterol. The brain is separated from the circulation by the blood brain barrier. While cholesterol will not passes this barrier, oxygenated forms of cholesterol can cross the barrier. Here by measuring the difference in the oxysterol content of blood plasma in the jugular vein and in a forearm vein by mass spectrometry (MS) we were able to determine the flux of more than 20 cholesterol metabolites between brain and the circulation. We confirm that 24S-hydroxycholesterol is exported from brain at a rate of about 2-3mg/24h. Gas chromatography (GC)-MS data shows that the cholesterol metabolites 5α-hydroxy-6-oxocholesterol (3β,5α-dihydroxycholestan-6-one), 7β-hydroxycholesterol and 7-oxocholesterol, generally considered to be formed through reactive oxygen species, are similarly exported from brain at rates of about 0.1, 2 and 2mg/24h, respectively. Although not to statistical significance both GC-MS and liquid chromatography (LC)-MS methods indicate that (25R)26-hydroxycholesterol is imported to brain, while LC-MS indicates that 7α-hydroxy-3-oxocholest-4-enoic acid is exported from brain. PMID:25668615

  17. Regulation of Vascular and Renal Function by Metabolite Receptors.

    PubMed

    Peti-Peterdi, János; Kishore, Bellamkonda K; Pluznick, Jennifer L

    2016-01-01

    To maintain metabolic homeostasis, the body must be able to monitor the concentration of a large number of substances, including metabolites, in real time and to use that information to regulate the activities of different metabolic pathways. Such regulation is achieved by the presence of sensors, termed metabolite receptors, in various tissues and cells of the body, which in turn convey the information to appropriate regulatory or positive or negative feedback systems. In this review, we cover the unique roles of metabolite receptors in renal and vascular function. These receptors play a wide variety of important roles in maintaining various aspects of homeostasis-from salt and water balance to metabolism-by sensing metabolites from a wide variety of sources. We discuss the role of metabolite sensors in sensing metabolites generated locally, metabolites generated at distant tissues or organs, or even metabolites generated by resident microbes. Metabolite receptors are also involved in various pathophysiological conditions and are being recognized as potential targets for new drugs. By highlighting three receptor families-(a) citric acid cycle intermediate receptors, (b) purinergic receptors, and PMID:26667077

  18. Reactive Metabolites: Current and Emerging Risk and Hazard Assessments.

    PubMed

    Thompson, Richard A; Isin, Emre M; Ogese, Monday O; Mettetal, Jerome T; Williams, Dominic P

    2016-04-18

    Although idiosyncratic adverse drug reactions are rare, they are still a major concern to patient safety. Reactive metabolites are widely accepted as playing a pivotal role in the pathogenesis of idiosyncratic adverse drug reactions. While there are today well established strategies for the risk assessment of stable metabolites within the pharmaceutical industry, there is still no consensus on reactive metabolite risk assessment strategies. This is due to the complexity of the mechanisms of these toxicities as well as the difficulty in identifying and quantifying short-lived reactive intermediates such as reactive metabolites. In this review, reactive metabolite risk and hazard assessment approaches are discussed, and their pros and cons highlighted. We also discuss the nature of idiosyncratic adverse drug reactions, using acetaminophen and nefazodone to exemplify the complexity of the underlying mechanisms of reactive metabolite mediated hepatotoxicity. One of the key gaps moving forward is our understanding of and ability to predict the contribution of immune activation in idiosyncratic adverse drug reactions. Sections are included on the clinical phenotypes of immune mediated idiosyncratic adverse drug reactions and on the present understanding of immune activation by reactive metabolites. The advances being made in microphysiological systems have a great potential to transform our ability to risk assess reactive metabolites, and an overview of the key components of these systems is presented. Finally, the potential impact of systems pharmacology approaches in reactive metabolite risk assessments is highlighted. PMID:26735163

  19. Blood styrene and urinary metabolites in styrene polymerisation.

    PubMed Central

    Wolff, M S; Lorimer, W V; Lilis, R; Selikoff, I J

    1978-01-01

    The results of the analysis of blood and urine samples for styrene and its metabolites in 491 workers in a styrene polymerisation plant in the United States are reported. The levels of exposure to styrene were estimated to be less than 10 ppm, but nevertheless styrene and metabolites were detectable in more than 50% of workers in polymerisation jobs, within 4 h of exposure. Workers involved in the manufacture and purification of styrene from ethyl benzene also had detectable blood styrene and urinary metabolites in 83% of recently exposed subjects. The relationship between styrene in blood and in subcutaneous fat and urinary metabolites as pharmacokinetic variables is discussed. PMID:737139

  20. Decreased lymphocyte responses in free-ranging bottlenose dolphins (Tursiops truncatus) are associated with increased concentrations of PCBs and DDT in peripheral blood.

    PubMed Central

    Lahvis, G P; Wells, R S; Kuehl, D W; Stewart, J L; Rhinehart, H L; Via, C S

    1995-01-01

    Since 1987, large-scale mortalities of dolphins have been reported along the Atlantic coast of North America, in the Gulf of Mexico, and in the Mediterranean Sea. Autopsied bottlenose dolphins, Tursiops truncatus, which were collected from the large-scale mortality along the Atlantic coast in 1987 to 1988, exhibited opportunistic infections indicative of immune dysfunction. Further, these animals had high levels of chlorinated hydrocarbons, such as PCBs and DDT, that can suppress immune functions. The purpose of this study was to determine whether there is a relationship between chemical contaminant exposure and immune response in free-ranging dolphins. In June of 1991, peripheral blood was obtained from members of a bottlenose dolphin population that resides along the west coast of Florida. Peripheral blood lymphocyte responses to Concanavalin A (Con A) and phytohemagglutinin (PHA) were determined in vitro and compared by regression analysis with contaminant concentrations in whole blood from a small subset of these animals (n = 5). These data indicate that a reduced immune response in these bottlenose dolphins was correlated with increasing whole blood concentrations of several contaminants. Specifically, inverse correlations were found between Con A-induced lymphocyte proliferation and tetrachlorinated to octachlorinated biphenyls (r2 values ranged from 0.70 to 0.87). Con A-induced lymphocyte responses also correlated inversely with p,p'DDT (r2 values of 0.73 and 0.79); o.p'-DDE (r2 values of 0.93 and 0.96); and p,p'-DDE (r2 values of 0.73 and 0.81). PMID:7556026

  1. Genetic Influences on Metabolite Levels: A Comparison across Metabolomic Platforms.

    PubMed

    Yet, Idil; Menni, Cristina; Shin, So-Youn; Mangino, Massimo; Soranzo, Nicole; Adamski, Jerzy; Suhre, Karsten; Spector, Tim D; Kastenmüller, Gabi; Bell, Jordana T

    2016-01-01

    Metabolomic profiling is a powerful approach to characterize human metabolism and help understand common disease risk. Although multiple high-throughput technologies have been developed to assay the human metabolome, no technique is capable of capturing the entire human metabolism. Large-scale metabolomics data are being generated in multiple cohorts, but the datasets are typically profiled using different metabolomics platforms. Here, we compared analyses across two of the most frequently used metabolomic platforms, Biocrates and Metabolon, with the aim of assessing how complimentary metabolite profiles are across platforms. We profiled serum samples from 1,001 twins using both targeted (Biocrates, n = 160 metabolites) and non-targeted (Metabolon, n = 488 metabolites) mass spectrometry platforms. We compared metabolite distributions and performed genome-wide association analyses to identify shared genetic influences on metabolites across platforms. Comparison of 43 metabolites named for the same compound on both platforms indicated strong positive correlations, with few exceptions. Genome-wide association scans with high-throughput metabolic profiles were performed for each dataset and identified genetic variants at 7 loci associated with 16 unique metabolites on both platforms. The 16 metabolites showed consistent genetic associations and appear to be robustly measured across platforms. These included both metabolites named for the same compound across platforms as well as unique metabolites, of which 2 (nonanoylcarnitine (C9) [Biocrates]/Unknown metabolite X-13431 [Metabolon] and PC aa C28:1 [Biocrates]/1-stearoylglycerol [Metabolon]) are likely to represent the same or related biochemical entities. The results demonstrate the complementary nature of both platforms, and can be informative for future studies of comparative and integrative metabolomics analyses in samples profiled on different platforms. PMID:27073872

  2. Genetic Influences on Metabolite Levels: A Comparison across Metabolomic Platforms

    PubMed Central

    Yet, Idil; Menni, Cristina; Shin, So-Youn; Mangino, Massimo; Soranzo, Nicole; Adamski, Jerzy; Suhre, Karsten; Spector, Tim D.

    2016-01-01

    Metabolomic profiling is a powerful approach to characterize human metabolism and help understand common disease risk. Although multiple high-throughput technologies have been developed to assay the human metabolome, no technique is capable of capturing the entire human metabolism. Large-scale metabolomics data are being generated in multiple cohorts, but the datasets are typically profiled using different metabolomics platforms. Here, we compared analyses across two of the most frequently used metabolomic platforms, Biocrates and Metabolon, with the aim of assessing how complimentary metabolite profiles are across platforms. We profiled serum samples from 1,001 twins using both targeted (Biocrates, n = 160 metabolites) and non-targeted (Metabolon, n = 488 metabolites) mass spectrometry platforms. We compared metabolite distributions and performed genome-wide association analyses to identify shared genetic influences on metabolites across platforms. Comparison of 43 metabolites named for the same compound on both platforms indicated strong positive correlations, with few exceptions. Genome-wide association scans with high-throughput metabolic profiles were performed for each dataset and identified genetic variants at 7 loci associated with 16 unique metabolites on both platforms. The 16 metabolites showed consistent genetic associations and appear to be robustly measured across platforms. These included both metabolites named for the same compound across platforms as well as unique metabolites, of which 2 (nonanoylcarnitine (C9) [Biocrates]/Unknown metabolite X-13431 [Metabolon] and PC aa C28:1 [Biocrates]/1-stearoylglycerol [Metabolon]) are likely to represent the same or related biochemical entities. The results demonstrate the complementary nature of both platforms, and can be informative for future studies of comparative and integrative metabolomics analyses in samples profiled on different platforms. PMID:27073872

  3. Characterization of Urinary Phthalate Metabolites Among Custodians.

    PubMed

    Cavallari, Jennifer M; Simcox, Nancy J; Wakai, Sara; Lu, Chensheng; Garza, Jennifer L; Cherniack, Martin

    2015-10-01

    Phthalates, a ubiquitous class of chemicals found in consumer, personal care, and cleaning products, have been linked to adverse health effects. Our goal was to characterize urinary phthalate metabolite concentrations and to identify work and nonwork sources among custodians using traditional cleaning chemicals and 'green' or environmentally preferable products (EPP). Sixty-eight custodians provided four urine samples on a workday (first void, before shift, end of shift, and before bedtime) and trained observers recorded cleaning tasks and types of products used (traditional, EPP, or disinfectant) hourly over the work shifts. Questionnaires were used to assess personal care product use. Four different phthalate metabolites [monoethyl phthalate (MEP), monomethyl phthalate (MMP), mono (2-ethylhexyl) phthalate (MEHP), and monobenzyl phthalate (MBzP)] were quantified using liquid chromatography mass spectrometry. Geometric means (GM) and 95% confidence intervals (95% CI) were calculated for creatinine-adjusted urinary phthalate concentrations. Mixed effects univariate and multivariate modeling, using a random intercept for each individual, was performed to identify predictors of phthalate metabolites including demographics, workplace factors, and personal care product use. Creatinine-adjusted urinary concentrations [GM (95% CI)] of MEP, MMP, MEHP, and MBzP were 107 (91.0-126), 2.69 (2.18-3.30), 6.93 (6.00-7.99), 8.79 (7.84-9.86) µg g(-1), respectively. An increasing trend in phthalate concentrations from before to after shift was not observed. Creatinine-adjusted urinary MEP was significantly associated with frequency of traditional cleaning chemical intensity in the multivariate model after adjusting for potential confounding by demographics, workplace factors, and personal care product use. While numerous demographics, workplace factors, and personal care products were statistically significant univariate predictors of MMP, MEHP, and MBzP, few associations persisted

  4. From the Lab Bench: Plant secondary metabolites: The good and the bad.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A column was written to discuss the negatives and positives of plant secondary metabolites. Primary metabolites are those metabolites that are required for survival, such as protein, carbohydrates, and lipids. Plant secondary metabolites are produced from primary metabolites and are not required f...

  5. Unique metabolites protect earthworms against plant polyphenols

    PubMed Central

    Liebeke, Manuel; Strittmatter, Nicole; Fearn, Sarah; Morgan, A. John; Kille, Peter; Fuchser, Jens; Wallis, David; Palchykov, Vitalii; Robertson, Jeremy; Lahive, Elma; Spurgeon, David J.; McPhail, David; Takáts, Zoltán; Bundy, Jacob G.

    2015-01-01

    All higher plants produce polyphenols, for defence against above-ground herbivory. These polyphenols also influence the soil micro- and macro-fauna that break down plant leaf litter. Polyphenols therefore indirectly affect the fluxes of soil nutrients and, ultimately, carbon turnover and ecosystem functioning in soils. It is unknown how earthworms, the major component of animal biomass in many soils, cope with high-polyphenol diets. Here, we show that earthworms possess a class of unique surface-active metabolites in their gut, which we term ‘drilodefensins'. These compounds counteract the inhibitory effects of polyphenols on earthworm gut enzymes, and high-polyphenol diets increase drilodefensin concentrations in both laboratory and field populations. This shows that drilodefensins protect earthworms from the harmful effects of ingested polyphenols. We have identified the key mechanism for adaptation to a dietary challenge in an animal group that has a major role in organic matter recycling in soils worldwide. PMID:26241769

  6. Unique metabolites protect earthworms against plant polyphenols.

    PubMed

    Liebeke, Manuel; Strittmatter, Nicole; Fearn, Sarah; Morgan, A John; Kille, Peter; Fuchser, Jens; Wallis, David; Palchykov, Vitalii; Robertson, Jeremy; Lahive, Elma; Spurgeon, David J; McPhail, David; Takáts, Zoltán; Bundy, Jacob G

    2015-01-01

    All higher plants produce polyphenols, for defence against above-ground herbivory. These polyphenols also influence the soil micro- and macro-fauna that break down plant leaf litter. Polyphenols therefore indirectly affect the fluxes of soil nutrients and, ultimately, carbon turnover and ecosystem functioning in soils. It is unknown how earthworms, the major component of animal biomass in many soils, cope with high-polyphenol diets. Here, we show that earthworms possess a class of unique surface-active metabolites in their gut, which we term 'drilodefensins'. These compounds counteract the inhibitory effects of polyphenols on earthworm gut enzymes, and high-polyphenol diets increase drilodefensin concentrations in both laboratory and field populations. This shows that drilodefensins protect earthworms from the harmful effects of ingested polyphenols. We have identified the key mechanism for adaptation to a dietary challenge in an animal group that has a major role in organic matter recycling in soils worldwide. PMID:26241769

  7. Encapsulates for Food Bioconversions and Metabolite Production

    NASA Astrophysics Data System (ADS)

    Breguet, Véronique; Vojinovic, Vojislav; Marison, Ian W.

    The control of production costs in the food industry must be very strict as a result of the relatively low added value of food products. Since a wide variety of enzymes and/or cells are employed in the food industry for starch processing, cheese making, food preservation, lipid hydrolysis and other applications, immobilization of the cells and/or enzymes has been recognized as an attractive approach to improving food processes while minimizing costs. This is due to the fact that biocatalyst immobilization allows for easier separation/purification of the product and reutilization of the biocatalyst. The advantages of the use of immobilized systems are many, and they have a special relevance in the area of food technology, especially because industrial processes using immobilized biosystems are usually characterized by lower capital/energy costs and better logistics. The main applications of immobilization, related to the major processes of food bioconversions and metabolite production, will be described and discussed in this chapter.

  8. Determination of Tamoxifen and its Major Metabolites in Exposed Fish

    EPA Science Inventory

    Tamoxifen (TAM), (Z)-1-(p-dimethylaminoethoxyphenyl)-1, 2-diphenyl-1-butene, is a nonsteroidal agent that has been used in breast cancer treatment for decades. Its major metabolites are 4-hydroxytamoxifen (4-OHT), N-desmethyltamoxifen (DMT), and endoxifen. While TAM and metabolit...

  9. Profiling Reactive Metabolites via Chemical Trapping and Targeted Mass Spectrometry.

    PubMed

    Chang, Jae Won; Lee, Gihoon; Coukos, John S; Moellering, Raymond E

    2016-07-01

    Metabolomic profiling studies aim to provide a comprehensive, quantitative, and dynamic portrait of the endogenous metabolites in a biological system. While contemporary technologies permit routine profiling of many metabolites, intrinsically labile metabolites are often improperly measured or omitted from studies due to unwanted chemical transformations that occur during sample preparation or mass spectrometric analysis. The primary glycolytic metabolite 1,3-bisphosphoglyceric acid (1,3-BPG) typifies this class of metabolites, and, despite its central position in metabolism, has largely eluded analysis in profiling studies. Here we take advantage of the reactive acylphosphate group in 1,3-BPG to chemically trap the metabolite with hydroxylamine during metabolite isolation, enabling quantitative analysis by targeted LC-MS/MS. This approach is compatible with complex cellular metabolome, permits specific detection of the reactive (1,3-) instead of nonreactive (2,3-) BPG isomer, and has enabled direct analysis of dynamic 1,3-BPG levels resulting from perturbations to glucose processing. These studies confirmed that standard metabolomic methods misrepresent cellular 1,3-BPG levels in response to altered glucose metabolism and underscore the potential for chemical trapping to be used for other classes of reactive metabolites. PMID:27314642

  10. Synthesis of an Albendazole Metabolite: Characterization and HPLC Determination

    ERIC Educational Resources Information Center

    Mahler, Graciela; Davyt, Danilo; Gordon, Sandra; Incerti, Marcelo; Nunez, Ivana; Pezaroglo, Horacio; Scarone, Laura; Serra, Gloria; Silvera, Mauricio; Manta, Eduardo

    2008-01-01

    In this laboratory activity, students are introduced to the synthesis of an albendazole metabolite obtained by a sulfide oxidation reaction. Albendazole as well as its metabolite, albendazole sulfoxide, are used as anthelmintic drugs. The oxidation reagent is H[subscript 2]O[subscript 2] in acetic acid. The reaction is environmental friendly,…

  11. Influence of abiotic stress signals on secondary metabolites in plants

    PubMed Central

    Ramakrishna, Akula; Ravishankar, Gokare Aswathanarayana

    2011-01-01

    Plant secondary metabolites are unique sources for pharmaceuticals, food additives, flavors, and industrially important biochemicals. Accumulation of such metabolites often occurs in plants subjected to stresses including various elicitors or signal molecules. Secondary metabolites play a major role in the adaptation of plants to the environment and in overcoming stress conditions. Environmental factors viz. temperature, humidity, light intensity, the supply of water, minerals, and CO2 influence the growth of a plant and secondary metabolite production. Drought, high salinity, and freezing temperatures are environmental conditions that cause adverse effects on the growth of plants and the productivity of crops. Plant cell culture technologies have been effective tools for both studying and producing plant secondary metabolites under in vitro conditions and for plant improvement. This brief review summarizes the influence of different abiotic factors include salt, drought, light, heavy metals, frost etc. on secondary metabolites in plants. The focus of the present review is the influence of abiotic factors on secondary metabolite production and some of important plant pharmaceuticals. Also, we describe the results of in vitro cultures and production of some important secondary metabolites obtained in our laboratory. PMID:22041989

  12. Spatial distribution of metabolites in the human lens.

    PubMed

    Tamara, Semen O; Yanshole, Lyudmila V; Yanshole, Vadim V; Fursova, Anjella Zh; Stepakov, Denis A; Novoselov, Vladimir P; Tsentalovich, Yuri P

    2016-02-01

    Spatial distribution of 34 metabolites along the optical and equatorial axes of the human lens has been determined. For the majority of metabolites, the homogeneous distribution has been observed. That suggests that the rate of the metabolite transformation in the lens is low due to the general metabolic passivity of the lens fiber cells. However, the redox processes are active in the lens; as a result, some metabolites, including antioxidants, demonstrate the "nucleus-depleted" type of distribution, whereas secondary UV filters show the "nucleus-enriched" type. The metabolite concentrations at the lens poles and equator are similar for all metabolites under study. The concentric pattern of the "nucleus-depleted" and "nucleus-enriched" distributions testifies that the metabolite distribution inside the lens is mostly governed by a passive diffusion, relatively free along the fiber cells and retarded in the radial direction across the cells. No significant difference in the metabolite distribution between the normal and cataractous human lenses was found. PMID:26500196

  13. Screening botanical extracts for quinoid metabolites.

    PubMed

    Johnson, B M; Bolton, J L; van Breemen, R B

    2001-11-01

    Botanical dietary supplements represent a significant share of the growing market for alternative medicine in the USA, where current regulations do not require assessment of their safety. To help ensure the safety of such products, an in vitro assay using pulsed ultrafiltration and LC-MS-MS has been developed to screen botanical extracts for the formation of electrophilic and potentially toxic quinoid species upon bioactivation by hepatic cytochromes P450. Rat liver microsomes were trapped in a flow-through chamber by an ultrafiltration membrane, and samples containing botanical extracts, GSH and NADP(H), were flow-injected into the chamber. Botanical compounds that were metabolized to reactive intermediates formed stable GSH adducts mimicking a common in vivo detoxification pathway. If present in the ultrafiltrate, GSH conjugates were detected using LC-MS-MS with precursor ion scanning followed by additional characterization using product ion scanning and comparison to standard compounds. As expected, no GSH adducts of reactive metabolites were found in extracts of Trifolium pratense L. (red clover), which are under investigation as botanical dietary supplements for the management of menopause. However, extracts of Sassafras albidum (Nutt.) Nees (sassafras), Symphytum officinale L. (comfrey), and Rosmarinus officinalis L. (rosemary), all of which are known to contain compounds that are either carcinogenic or toxic to mammals, produced GSH adducts during this screening assay. Several compounds that formed GSH conjugates including novel metabolites of rosmarinic acid were identified using database searching and additional LC-MS-MS studies. This assay should be useful as a preliminary toxicity screen during the development of botanical dietary supplements. A positive test suggests that additional toxicological studies are warranted before human consumption of a botanical product. PMID:11712913

  14. Metabolite Proofreading in Carnosine and Homocarnosine Synthesis

    PubMed Central

    Veiga-da-Cunha, Maria; Chevalier, Nathalie; Stroobant, Vincent; Vertommen, Didier; Van Schaftingen, Emile

    2014-01-01

    Carnosine synthase is the ATP-dependent ligase responsible for carnosine (β-alanyl-histidine) and homocarnosine (γ-aminobutyryl-histidine) synthesis in skeletal muscle and brain, respectively. This enzyme uses, also at substantial rates, lysine, ornithine, and arginine instead of histidine, yet the resulting dipeptides are virtually absent from muscle or brain, suggesting that they are removed by a “metabolite repair” enzyme. Using a radiolabeled substrate, we found that rat skeletal muscle, heart, and brain contained a cytosolic β-alanyl-lysine dipeptidase activity. This enzyme, which has the characteristics of a metalloenzyme, was purified ≈200-fold from rat skeletal muscle. Mass spectrometry analysis of the fractions obtained at different purification stages indicated parallel enrichment of PM20D2, a peptidase of unknown function belonging to the metallopeptidase 20 family. Western blotting showed coelution of PM20D2 with β-alanyl-lysine dipeptidase activity. Recombinant mouse PM20D2 hydrolyzed β-alanyl-lysine, β-alanyl-ornithine, γ-aminobutyryl-lysine, and γ-aminobutyryl-ornithine as its best substrates. It also acted at lower rates on β-alanyl-arginine and γ-aminobutyryl-arginine but virtually not on carnosine or homocarnosine. Although acting preferentially on basic dipeptides derived from β-alanine or γ-aminobutyrate, PM20D2 also acted at lower rates on some “classic dipeptides” like α-alanyl-lysine and α-lysyl-lysine. The same activity profile was observed with human PM20D2, yet this enzyme was ∼100–200-fold less active on all substrates tested than the mouse enzyme. Cotransfection in HEK293T cells of mouse or human PM20D2 together with carnosine synthase prevented the accumulation of abnormal dipeptides (β-alanyl-lysine, β-alanyl-ornithine, γ-aminobutyryl-lysine), thus favoring the synthesis of carnosine and homocarnosine and confirming the metabolite repair role of PM20D2. PMID:24891507

  15. Effects of polychlorobiphenyls, polybromodiphenylethers, organochlorine pesticides and their metabolites on vitamin A status in lactating grey seals.

    PubMed

    Vanden Berghe, Marie; Weijs, Liesbeth; Habran, Sarah; Das, Krishna; Bugli, Céline; Pillet, Stéphane; Rees, Jean-François; Pomeroy, Paddy; Covaci, Adrian; Debier, Cathy

    2013-01-01

    Polychlorobiphenyls (PCBs), polybromodiphenylethers (PBDEs) and organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and hexachlorobenzene (HCB), are considered as endocrine disruptors in laboratory and wild animals. This study investigated whether these compounds and their hydroxylated metabolites (HO-PCBs and HO-PBDEs) may affect the homoeostasis of vitamin A, a dietary hormone, in the blubber and serum of twenty lactating grey seals sampled at early and late lactation on the Isle of May, Scotland. The effect of naturally produced compounds such as the methoxylated (MeO)-PBDEs was also examined. Vitamin A levels in inner blubber (37±9 μg/g wet weight (ww) and 92±32 μg/g ww at early and late lactation, respectively) and serum (408±143 and 390±98 ng/ml at early and late lactation, respectively) appeared to be positively related to ΣPCBs, ΣPBDEs and several individual PCB and PBDE congeners in inner blubber and serum. These findings may suggest enhanced mobilisation of hepatic retinoid stores and redistribution in the blubber, a storage site for vitamin A in marine mammals. We have also reported that serum concentrations of ΣHO-PCBs and 4-OH-CB107 tended to increase with circulating vitamin A levels. Although the direction of the relationships may sometimes differ from those reported in the literature, our results are in agreement with previous findings highlighting a disruption of vitamin A homoeostasis in the blubber and bloodstream following exposure to environmental pollutants. The fact that vitamin A and PCBs appeared to share common mechanisms of mobilisation and transfer during lactation in grey seals (Debier et al., 2004; Vanden Berghe et al., 2010) may also play a role in the different relationships observed between vitamin A and lipophilic pollutants. PMID:23051620

  16. Software-assisted serum metabolite quantification using NMR.

    PubMed

    Jung, Young-Sang; Hyeon, Jin-Seong; Hwang, Geum-Sook

    2016-08-31

    The goal of metabolomics is to analyze a whole metabolome under a given set of conditions, and accurate and reliable quantitation of metabolites is crucial. Absolute concentration is more valuable than relative concentration; however, the most commonly used method in NMR-based serum metabolic profiling, bin-based and full data point peak quantification, provides relative concentration levels of metabolites and are not reliable when metabolite peaks overlap in a spectrum. In this study, we present the software-assisted serum metabolite quantification (SASMeQ) method, which allows us to identify and quantify metabolites in NMR spectra using Chenomx software. This software uses the ERETIC2 utility from TopSpin to add a digitally synthesized peak to a spectrum. The SASMeQ method will advance NMR-based serum metabolic profiling by providing an accurate and reliable method for absolute quantification that is superior to bin-based quantification. PMID:27506360

  17. Urinary pesticide metabolites in school students from northern Thailand.

    PubMed

    Panuwet, Parinya; Prapamontol, Tippawan; Chantara, Somporn; Barr, Dana B

    2009-05-01

    We evaluated exposure to pesticides among secondary school students aged 12-13 years old in Chiang Mai Province, Thailand. Pesticide-specific urinary metabolites were used as biomarkers of exposure for a variety of pesticides, including organophosphorus insecticides, synthetic pyrethroid insecticides and selected herbicides. We employed a simple solid-phase extraction with analysis using isotope dilution high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). A total of 207 urine samples from Thai students were analyzed for 18 specific pesticide metabolites. We found 14 metabolites in the urine samples tested; seven of them were detected with a frequency > or=17%. The most frequently detected metabolites were 2-[(dimethoxyphosphorothioyl) sulfanyl] succinic acid (malathion dicarboxylic acid), para-nitrophenol (PNP), 3,5,6-trichloro-2-pyridinol (TPCY; metabolite of chlorpyrifos), 2,4-dichlorophenoxyacetic acid (2,4-D), cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acids (c-DCCA and t-DCCA; metabolite of permethrin) and 3-phenoxybenzoic acid (3-PBA; metabolite of pyrethroids). The students were classified into 4 groups according to their parental occupations: farmers (N=60), merchants and traders (N=39), government and company employees (N=52), and laborers (N=56). Children of farmers had significantly higher urinary concentrations of pyrethroid insecticide metabolites than did other children (p<0.05). Similarly, children of agricultural families had significantly higher pyrethroid metabolite concentrations. Males had significantly higher values of PNP (Mann-Whitney test, p=0.009); however, no other sex-related differences were observed. Because parental occupation and agricultural activities seemed to have little influence on pesticide levels, dietary sources were the likely contributors to the metabolite levels observed. PMID:18760967

  18. Steady-State Metabolite Concentrations Reflect a Balance between Maximizing Enzyme Efficiency and Minimizing Total Metabolite Load

    PubMed Central

    Amador-Noguez, Daniel; Haraldsdóttir, Hulda S.; Milo, Ron; Rabinowitz, Josh; Liebermeister, Wolfram; Shlomi, Tomer

    2013-01-01

    Steady-state metabolite concentrations in a microorganism typically span several orders of magnitude. The underlying principles governing these concentrations remain poorly understood. Here, we hypothesize that observed variation can be explained in terms of a compromise between factors that favor minimizing metabolite pool sizes (e.g. limited solvent capacity) and the need to effectively utilize existing enzymes. The latter requires adequate thermodynamic driving force in metabolic reactions so that forward flux substantially exceeds reverse flux. To test this hypothesis, we developed a method, metabolic tug-of-war (mTOW), which computes steady-state metabolite concentrations in microorganisms on a genome-scale. mTOW is shown to explain up to 55% of the observed variation in measured metabolite concentrations in E. coli and C. acetobutylicum across various growth media. Our approach, based strictly on first thermodynamic principles, is the first method that successfully predicts high-throughput metabolite concentration data in bacteria across conditions. PMID:24086517

  19. A case report of motor neuron disease in a patient showing significant level of DDTs, HCHs and organophosphate metabolites in hair as well as levels of hexane and toluene in blood.

    PubMed

    Kanavouras, Konstantinos; Tzatzarakis, Manolis N; Mastorodemos, Vasileios; Plaitakis, Andreas; Tsatsakis, Aristidis M

    2011-11-01

    Motor neuron disease is a devastating neurodegenerative condition, with the majority of sporadic, non-familial cases being of unknown etiology. Several epidemiological studies have suggested that occupational exposure to chemicals may be associated with disease pathogenesis. We report the case of a patient developing progressive motor neuron disease, who was chronically exposed to pesticides and organic solvents. The patient presented with leg spasticity and developed gradually clinical signs suggestive of amyotrophic lateral sclerosis, which was supported by the neurophysiologic and radiological findings. Our report is an evidence based case of combined exposure to organochlorine (DDTs), organophosphate pesticides (OPs) and organic solvents as confirmed by laboratory analysis in samples of blood and hair confirming systematic exposure. The concentration of non-specific dialkylphosphates metabolites (DAPs) of OPs in hair (dimethyphopshate (DMP) 1289.4 pg/mg and diethylphosphate (DEP) 709.4 pg/mg) and of DDTs (opDDE 484.0 pg/mg, ppDDE 526.6 pg/mg, opDDD 448.4 pg/mg, ppDDD+opDDT 259.9 pg/mg and ppDDT 573.7 pg/mg) were considerably significant. Toluene and n-hexane were also detected in blood on admission at hospital and quantified (1.23 and 0.87 μg/l, respectively), while 3 months after hospitalization blood testing was found negative for toluene and n-hexane and hair analysis was provided decrease levels of HCHs, DDTs and DAPs. PMID:21851830

  20. Secondary Metabolites from Higher Fungi: Discovery, Bioactivity, and Bioproduction

    NASA Astrophysics Data System (ADS)

    Zhong, Jian-Jiang; Xiao, Jian-Hui

    Medicinal higher fungi such as Cordyceps sinensis and Ganoderma lucidum have been used as an alternative medicine remedy to promote health and longevity for people in China and other regions of the world since ancient times. Nowadays there is an increasing public interest in the secondary metabolites of those higher fungi for discovering new drugs or lead compounds. Current research in drug discovery from medicinal higher fungi involves a multifaceted approach combining mycological, biochemical, pharmacological, metabolic, biosynthetic and molecular techniques. In recent years, many new secondary metabolites from higher fungi have been isolated and are more likely to provide lead compounds for new drug discovery, which may include chemopreventive agents possessing the bioactivity of immunomodulatory, anticancer, etc. However, numerous challenges of secondary metabolites from higher fungi are encountered including bioseparation, identification, biosynthetic metabolism, and screening model issues, etc. Commercial production of secondary metabolites from medicinal mushrooms is still limited mainly due to less information about secondary metabolism and its regulation. Strategies for enhancing secondary metabolite production by medicinal mushroom fermentation include two-stage cultivation combining liquid fermentation and static culture, two-stage dissolved oxygen control, etc. Purification of bioactive secondary metabolites, such as ganoderic acids from G. lucidum, is also very important to pharmacological study and future pharmaceutical application. This review outlines typical examples of the discovery, bioactivity, and bioproduction of secondary metabolites of higher fungi origin.