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1

A Test House Study of Pesticides and PesticideDegradation Products Following an Indoor Application  

EPA Science Inventory

Preexisting pesticide degradates are a concern for pesticide biomonitoring studies as exposure to them may result in overestimation of pesticide exposure. The purpose of this research was to determine whether there was significant formation and movement, of pesticide degradates o...

2

MECHANISMS OF PESTICIDE DEGRADATION  

EPA Science Inventory

This research project was initiated with the overall objective of determining (1) the chemical structures of toxic components of toxaphene, (2) to study anaerobic metabolism to degrade toxaphene and other pesticides, and (3) to understand toxic action mechanism of chlordimeform. ...

3

Occurrence of pesticides and some of their degradation products in waters in a Spanish wine region  

NASA Astrophysics Data System (ADS)

SummaryA multi-residual analytical method based on solid phase extraction (SPE) followed by liquid chromatography-electrospray ionisation-mass spectrometry (LC-MS) was developed to monitor pesticides in natural waters. Fifty-eight compounds, including herbicides, fungicides, insecticides and some of their degradation products, were surveyed to evaluate the quality of natural waters throughout the wine-growing region of La Rioja (Rioja DOCa). Ninety-two sampling points were selected, including surface and ground waters that could be affected by agricultural activities covering the region's three sub-areas. Different parameters that may affect the efficiency of the SPE procedure were optimised (sorbent type, elution solvent and sample volume), and matrix-matched standards were used to eliminate the variable matrix effect and ensure good quantification. The developed method allows the determination of target compounds below the level established by the European Union for waters for human use with suitable precision (relative standard deviations lower than 18%) and accuracy (with recoveries over 61%). Forty compounds included in this study (six insecticides, 12 herbicides, 16 fungicides and six degradation products) were detected in one or more samples. The herbicides terbuthylazine, its metabolite desethyl terbuthylazine, fluometuron and ethofumesate and the fungicides pyrimethanil and tebuconazole were the compounds most frequently detected in water samples (present in more than 60% of the samples). Concentrations above 0.1 ?g L-1 were detected for 37 of the compounds studied, and in several cases recorded values of over 18 ?g L-1. The results reveal the presence of pesticides in most of the samples investigated. In 64% of groundwaters and 62% of surface waters, the sum of compounds detected was higher than 0.5 ?g L-1 (the limit established by EU legislation for the sum of all pesticides detected in waters for human use).

Herrero-Hernández, E.; Andrades, M. S.; Álvarez-Martín, A.; Pose-Juan, E.; Rodríguez-Cruz, M. S.; Sánchez-Martín, M. J.

2013-04-01

4

Determination of atrazine and degradation products in Luxembourgish drinking water: origin and fate of potential endocrine-disrupting pesticides  

Microsoft Academic Search

Several pesticides have been hypothesized to act as endocrine-disrupting compounds, exhibiting hormonal activity and perturbing normal physiological functions. Among these, especially s-triazine herbicides have received increased attention. Despite being banned in many countries, including the European Union, atrazine is still the world's most widely used herbicide. Despite its discontinued use, considerable concentrations of atrazine and its degradation products, mainly desethylatrazine

T. Bohn; E. Cocco; L. Gourdol; C. Guignard; L. Hoffmann

2011-01-01

5

Enzyme stabilization for pesticide degradation  

Microsoft Academic Search

Enzymes offer inherent advantages and limitations as active components of formulations used to decontaminate soil and equipment contaminated with toxic materials such as pesticides. Because of the catalytic nature of enzymes, each molecule of enzyme has the potential to destroy countless molecules of a contaminating toxic compound. This degradation takes place under mild environmental conditions of pH, temperature, pressure, and

D. B. Rivers; F FRAZERIII; D. W. Mason; T. R. Tice

1988-01-01

6

Determination of the pesticide naptalam and its degradation products by positive and negative ion mass spectrometry  

Microsoft Academic Search

N-1-Naphthylphtalamic acid (naptalam) and its degradation products, 1-naphthylamine and N-(1-naphthyl) phthalimide were simultaneously determined in river water by two independent mass spectrometric (MS) methods.\\u000a These were negative ion MS (NIMS) and programmable temperature vaporizer gas chromatography mass spectrometry (PTV-GC MS)\\u000a with electron impact ionization (positive ions). Prior to the NIMS analysis, the samples were preconcentrated by solid phase\\u000a extraction (SPE)

Alireza Ghassempour; Mohammad Reza Arshadi; Feridoun Salek Asghari

2001-01-01

7

Illegal Pesticide Products  

MedlinePLUS

Illegal Pesticide Products Esta página Web está disponible en espańol Quick Resources Protect your Business Counterfeit Flea and Tick Products for ... clear directions and safety warnings. Common Illegal Pest Products mothballs | pet products | insecticidal chalk | " Tres Pasitos " | antibacterial ...

8

Enzyme stabilization for pesticide degradation  

SciTech Connect

Enzymes offer inherent advantages and limitations as active components of formulations used to decontaminate soil and equipment contaminated with toxic materials such as pesticides. Because of the catalytic nature of enzymes, each molecule of enzyme has the potential to destroy countless molecules of a contaminating toxic compound. This degradation takes place under mild environmental conditions of pH, temperature, pressure, and solvent. The basic limitation of enzymes is their degree of stability during storage and application conditions. Stabilizing methods such as the use of additives, covalent crosslinking, covalent attachment, gel entrapment, and microencapsulation have been directed developing an enzyme preparation that is stable under extremes of pH, temperature, and exposure to organic solvents. Initial studies were conducted using the model enzymes subtilisin and horseradish peroxidase.

Rivers, D.B.; Frazer, F.R. III; Mason, D.W.; Tice, T.R.

1988-01-01

9

MICROBIAL DEGRADATION OF PESTICIDES IN FRESHWATER STREAMS  

EPA Science Inventory

An overview is provided of studies of the microbial degradation of pesticides in streams, including research to understand the kinetics governing the rates of degradation. Most of these projects have related to the development of mathematical models that predict degradation of a ...

10

Determination of atrazine and degradation products in Luxembourgish drinking water: origin and fate of potential endocrine-disrupting pesticides.  

PubMed

Several pesticides have been hypothesized to act as endocrine-disrupting compounds, exhibiting hormonal activity and perturbing normal physiological functions. Among these, especially s-triazine herbicides have received increased attention. Despite being banned in many countries, including the European Union, atrazine is still the world's most widely used herbicide. Despite its discontinued use, considerable concentrations of atrazine and its degradation products, mainly desethylatrazine (DEA) and deisopropylatrazine (DIA), are still found in the environment, including drinking water sources. The aim of this investigation was to study concentrations of especially s-triazine herbicides and major degradation products in drinking water, including spring water, tap water and bottled water in Luxembourg. Spring water (2007/2008/2009, n?=?69/69/69), tap water (2008/2009, n?=?19/26), and bottled water (2007/2008/2009, n?=?5/13/7) were sampled at locations in Luxembourg and investigated for pesticides by LC-ESI-MS/MS. Atrazine was the predominant triazine, detectable in many spring water locations, tap and bottled water, ranging (mean) from 0-57 (9), 0-44 (4), and 0-4 (1) ng?l(-1), respectively. DEA and DIA in spring water ranged (mean) from 0-120 (19) and 0-27 (3) ng?l(-1), with higher concentrations from agricultural areas and low molar ratios of DEA:atrazine <0.5 and high ratios of atrazine:nitrate suggesting point-source contamination. Levels (mean) of DEA and DIA in tap water were 0-62 (14) and 0-6 (<1) ng?l(-1) and in bottled water 0-11 (2) and 0-7 (2) ng?l(-1). Simazine and other triazines were detected in traces (<5?ng?l(-1)). Thus, the conducted monitoring suggested the presence of low concentrations of s-triazines in raw and finished water, presumably partly due to non-agricultural contamination, with concentrations being below thresholds advocated by the European Union Directive 98/83/EC. PMID:21707270

Bohn, T; Cocco, E; Gourdol, L; Guignard, C; Hoffmann, L

2011-08-01

11

Assessment of priority pesticides, degradation products, and pesticide adjuvants in groundwaters and top soils from agricultural areas of the Ebro river basin.  

PubMed

Gas chromatography-mass spectrometry (GC/MS) was employed for the determination of 30 widely used pesticides including various transformation products and alkylphenols in water and agricultural soils with the aim of assessing the impact of these compounds in agricultural soils and the underlying aquifer. The extraction, clean-up, and analytical procedures were optimized for both water and soil samples to provide a highly robust method capable of determining target analytes at the ppb-ppt level with high precision. For water samples, different solid-phase extraction cartridges and conditions were optimized; similarly, pressurized liquid extraction conditions were tested to provide interference-free extracts and high sensitivity. Instrumental LODs of 3-4 pg were obtained. The multi-residue extraction procedures were applied to the analysis of groundwaters and agricultural soils from the Ebro river basin (NE Spain). Most ubiquitous herbicides detected were triazines but some acetanilides and organophosphorus pesticides were also found; the pesticide additive tributylphosphate was found in all water samples. Levels varied between 0.57 and 5.37 microg/L in groundwater, whereas nonylphenol was the sole compound detected in soil. Alkylphenols are used as adjuvants in pesticide formulations and are present in sludges employed as soil fertilizers. Occurrence was found to be similar to other environmental studies. PMID:17211597

Hildebrandt, Alain; Lacorte, Sílvia; Barceló, Damiŕ

2007-02-01

12

Assessment of priority pesticides, degradation products, and pesticide adjuvants in groundwaters and top soils from agricultural areas of the Ebro river basin  

Microsoft Academic Search

Gas chromatography-mass spectrometry (GC\\/MS) was employed for the determination of 30 widely used pesticides including various\\u000a transformation products and alkylphenols in water and agricultural soils with the aim of assessing the impact of these compounds\\u000a in agricultural soils and the underlying aquifer. The extraction, clean-up, and analytical procedures were optimized for both\\u000a water and soil samples to provide a highly

Alain Hildebrandt; Sílvia Lacorte; Damiŕ Barceló

2007-01-01

13

Organochlorinated pesticide degrading microorganisms isolated from contaminated soil.  

PubMed

Degradation of selected organochlorinated pesticides (?-hexachlorocyclohexane - ?-HCH, dichlorodiphenyltrichloroethane - DDT, hexachlorobenzene - HCB) by soil microorganisms was studied. Bacterial strains isolated from contaminated soil from Klatovy-Luby, Hajek and Neratovice, Czech Republic, capable of growth on the selected pesticides were isolated and characterised. These isolates were subjected to characterisation and identification by MS MALDI-TOF of whole cells and sequence analysis of 16S rRNA genes. The isolates were screened by gas chromatography for their ability to degrade the selected pesticides. Some isolates were able to degrade pesticides, and the formation of degradation products (?-pentachlorocyclohexane (?-PCCH), dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD)) observed in liquid culture confirmed their degradation capability. The isolates and DNA samples isolated from the contaminated soil were also screened for the bphA1 gene (encoding biphenyl-2,3-dioxygenase, the first enzyme in the PCB degradation pathway) and its occurrence was demonstrated. The isolates were also screened for the presence of linA, encoding dehydrochlorinase, the first enzyme of the HCH degradation pathway. The linA gene could not be found in any of the tested isolates, possibly due to the high specificity of the primers used. The isolates with the most effective degradation abilities could be used for further in situ bioremediation experiments with contaminated soil. PMID:25094051

Lovecka, Petra; Pacovska, Iva; Stursa, Petr; Vrchotova, Blanka; Kochankova, Lucie; Demnerova, Katerina

2015-01-25

14

Determination of antifouling pesticides and their degradation products in marine sediments by means of ultrasonic extraction and HPLC–APCI–MS  

Microsoft Academic Search

A method has been developed for the simultaneous determination of antifouling pesticides and some of their degradation products,\\u000a e.g. dichlofluanid, diuron, demethyldiuron, 1-(3,4-dichlorophenyl)urea, sea-nine, Irgarol 1051 and one of its metabolites\\u000a (2-methylthio-4-tert-butylamino-s-triazine) in marine sediments. The determination of these compounds in sediment samples was performed by means of methanolic\\u000a ultrasonic extraction then clean-up on an Isolute ENV+ solid phase extraction

K. Martínez; D. Barceló

2001-01-01

15

75 FR 34448 - Pesticides; Draft Guidance for Pesticide Registrants on False or Misleading Pesticide Product...  

Federal Register 2010, 2011, 2012, 2013

...on False or Misleading Pesticide Product Brand Names; Extension of Comment Period AGENCY...False or Misleading Pesticide Product Brand Names.'' This document extends the comment...False or Misleading Pesticide Product Brand Names.'' EPA is hereby extending...

2010-06-17

16

Microbial degradation of an organophosphate pesticide, malathion.  

PubMed

Organophosphorus pesticide, malathion, is used in public health, residential, and agricultural settings worldwide to control the pest population. It is proven that exposure to malathion produce toxic effects in humans and other mammals. Due to high toxicity, studies are going on to design effective methods for removal of malathion and its associated compounds from the environment. Among various techniques available, degradation of malathion by microbes proves to be an effective and environment friendly method. Recently, research activities in this area have shown that a diverse range of microorganisms are capable of degrading malathion. Therefore, we aimed at providing an overview of research accomplishments on this subject and discussed the toxicity of malathion and its metabolites, various microorganisms involved in its biodegradation and effect of various environmental parameters on its degradation. PMID:23442144

Singh, Baljinder; Kaur, Jagdeep; Singh, Kashmir

2014-05-01

17

ORGANOPHOSPHATE PESTICIDE DEGRADATION UNDER DRINKING WATER TREATMENT CONDITIONS: MODELING PERSPECTIVES  

EPA Science Inventory

The objectives of this work were to develop experimental approaches and a modeling philosophy to study degradation of organophosphate pesticides as a class under drinking water treatment conditions....

18

75 FR 28012 - Pesticides; Draft Guidance for Pesticide Registrants on False or Misleading Pesticide Product...  

Federal Register 2010, 2011, 2012, 2013

...ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2010-0282; FRL-8824-8] Pesticides; Draft Guidance for Pesticide Registrants on False or Misleading Pesticide Product Brand Names AGENCY: Environmental Protection Agency (EPA)....

2010-05-19

19

The effects of pesticide mixtures on degradation of pendimethalin in soils.  

PubMed

Most agronomic situations involve a sequence of herbicide, fungicide, and insecticide application. On the other hand, use of pesticidal combinations has become a standard practice in the production of many agricultural crops. One of the most important processes influencing the behavior of a pesticide in the environment is its degradation in soil. It is known that due to several pesticide applications in one vegetation season, the pesticide may be present in mixtures with other pesticides or xenobiotics in soil. This study examines the role which a mixture of chemicals plays in pesticide degradation. The influence of other pesticides on the rate of pendimethalin (PDM) degradation in soil was measured in controlled conditions. Mixtures of PDM with mancozeb or mancozeb and thiamethoxam significantly influenced the degradation of pendimethalin under controlled conditions. The second type of mixtures, with metribuzin or thiamethoxam, did not affect the behavior of pendimethalin in soil. Also, we determined the influence of water content on the rate of pendimethalin degradation alone in two soils and compared it to the rate in three pesticide mixtures. We compared two equations to evaluate the predictors of the rate of herbicide dissipation in soil: the first-order kinetic and the non-linear empirical models. We used the non-linear empirical model assuming that the degradation rate of a herbicide in soil is proportional to the difference of the observed concentration of herbicide in soil at time and concentration of herbicide in the last day of measurement. PMID:21713483

Swarcewicz, Maria K; Gregorczyk, Andrzej

2012-05-01

20

Effect of household and industrial processing on the levels of pesticide residues and degradation products in melons  

Microsoft Academic Search

Two varieties of melons (Cucumis melo) were treated with two fungicides (carbendazim and maneb) and four insecticides (acetamiprid, cyromazin, imazalil and thiamethoxam) to quantify the effect of household processing on the pesticide residues. To ensure sufficiently high levels of residues in flesh and peel, the most concentrated formulations were applied observing good agricultural practice. The peeling step decreased the concentration

A. Bonnechčre; V. Hanot; C. Bragard; T. Bedoret; J. van Loco

2012-01-01

21

Biotic and abiotic degradation of pesticide Dufulin in soils.  

PubMed

Dufulin is a newly developed antiviral agent (or pesticide) that activates systemic acquired resistance of plants. This pesticide is widely used in China to prevent abroad viral diseases in rice, tobacco and vegetables. In this study, the potential impacts such as soil type, moisture, temperature, and other factors on Dufulin degradation in soil were investigated. Degradation of Dufulin followed the first-order kinetics. The half-life values varied from 2.27 to 150.68 days. The dissipation of Dufulin was greatly affected by soil types, with DT50 (Degradation half time) varying between 17.59, 31.36, and 43.32 days for Eutric Gleysols, Cumulic Anthrosols, and Dystric Regosols, respectively. The elevated moisture accelerated the decay of Dufulin in soil. Degradation of Dufulin increased with temperature and its half-life values ranged from 16.66 to 42.79 days. Sterilization of soils and treatment with H2O2 resulted in a 6- and 8-fold decrease in degradation rates compared to the control, suggesting that Dufulin degradation was largely governed by microbial processes. Under different light spectra, the most effective degradation occurred with 100-W UV light (DT50=2.27 days), followed by 15-W UV light (DT50=8.32 days) and xenon light (DT50=14.26 days). Analysis by liquid chromatography-mass spectroscopy (LC-MS) revealed that 2-amino-4-methylbenzothiazole was one of the major decayed products of Dufulin in soils, suggesting that elimination of diethyl phosphate and 2-fluorobenzaldehyde was most like the degradation pathway of Dufulin in Eutric Gleysols. PMID:24323324

Wang, Hua Zi; Zuo, Hai Gen; Ding, Ya Juan; Miao, Shan Shan; Jiang, Chen; Yang, Hong

2014-03-01

22

Antimicrobial Pesticide Products  

MedlinePLUS

... growth of microorganisms. Because these products are used in or on living humans or animals, they are considered drugs and are thus approved and regulated by the Food and Drug Administration (FDA).

23

Simultaneous Degradation of Organophosphorus Pesticides and  

E-print Network

) pesticides and p-nitrophenol (PNP). The truncated ice nucleation protein (INPNC) anchor was used to target was 0.6 lmol/h/mg dry weight, 1.5 lmol/h/mg dry weight, and 9.0 lmol/h/mg dry weight for methyl

Chen, Wilfred

24

Application of microbial hot spots enhances pesticide degradation in soils  

Microsoft Academic Search

Through transfer of an active, isoproturon degrading microbial community, pesticide mineralization could be successfully enhanced in various soils under laboratory and outdoor conditions. The microbes, extracted from a soil having high native ability to mineralize this chemical, were established on expanded clay particles and distributed to various soils in the form of microbial “hot spots”. Both, diffusion controlled isoproturon mass

Sabine Grundmann; Roland Fuß; Michael Schmid; Manuela Laschinger; Bernhard Ruth; Rainer Schulin; Jean Charles Munch; Reiner Schroll

2007-01-01

25

75 FR 44954 - Product Cancellation Order for Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...FIFRA provides that a registrant of a pesticide product may at any time request that any of its pesticide registrations be canceled or amended to...stocks are those stocks of registered pesticide products which are currently in the...

2010-07-30

26

Avoid Counterfeit Pesticide Products for Dogs and Cats  

MedlinePLUS

Avoid Counterfeit Pesticide Products for Dogs and Cats EPA is aware of counterfeit pet pesticides designed to look like legitimately registered pesticide products. The information on this page is intended to ...

27

Ozone\\/Ultrasound Degradation Effect on Residual Pesticides in Commercially Available Apples  

Microsoft Academic Search

Ozone\\/ultrasound process is a promising method for treating refractory organics. Nevertheless, little is known about the ozone\\/ultrasound degradation effect on residual pesticides in fruits and vegetables. In this work, the presence of residual pesticides and the ozone\\/ultrasound degradation effect on pesticides in commercially available apples were investigated. Four pesticides, i.e. malathion, diphenylamine, carbendazim, and chlorothalonil were found in the assayed

Jijun Gong; Zhonghai Li; Haiyan Zhong; Jing Tang; Yinghong Li

2011-01-01

28

40 CFR 165.23 - Scope of pesticide products included.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Scope of pesticide products included. 165.23 Section 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Nonrefillable...

2011-07-01

29

40 CFR 165.23 - Scope of pesticide products included.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Scope of pesticide products included. 165.23 Section 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Nonrefillable...

2010-07-01

30

40 CFR 165.63 - Scope of pesticide products included.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Scope of pesticide products included. 165.63 Section 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2010-07-01

31

40 CFR 165.43 - Scope of pesticide products included.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Scope of pesticide products included. 165.43 Section 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Refillable...

2011-07-01

32

40 CFR 165.63 - Scope of pesticide products included.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Scope of pesticide products included. 165.63 Section 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2011-07-01

33

40 CFR 165.43 - Scope of pesticide products included.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Scope of pesticide products included. 165.43 Section 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Refillable...

2010-07-01

34

40 CFR 158.2070 - Biochemical pesticides product performance data requirements.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Biochemical pesticides product performance data requirements...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides §...

2010-07-01

35

40 CFR 158.2081 - Experimental use permit biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2011 CFR

...false Experimental use permit biochemical pesticides product chemistry data requirements table...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides §...

2011-07-01

36

40 CFR 158.2081 - Experimental use permit biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2010 CFR

...false Experimental use permit biochemical pesticides product chemistry data requirements table...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides §...

2010-07-01

37

40 CFR 158.2171 - Experimental use permit microbial pesticides product analysis data requirements table.  

Code of Federal Regulations, 2011 CFR

...false Experimental use permit microbial pesticides product analysis data requirements table...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2171...

2011-07-01

38

40 CFR 158.2171 - Experimental use permit microbial pesticides product analysis data requirements table.  

Code of Federal Regulations, 2010 CFR

...false Experimental use permit microbial pesticides product analysis data requirements table...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2171...

2010-07-01

39

40 CFR 158.2070 - Biochemical pesticides product performance data requirements.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Biochemical pesticides product performance data requirements...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides §...

2011-07-01

40

40 CFR 152.10 - Products that are not pesticides because they are not intended for a pesticidal purpose.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Products that are not pesticides because they are not intended for a pesticidal...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES...

2011-07-01

41

40 CFR 152.10 - Products that are not pesticides because they are not intended for a pesticidal purpose.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Products that are not pesticides because they are not intended for a pesticidal...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES...

2010-07-01

42

Natural products as sources for new pesticides.  

PubMed

Natural products as pesticides have been reviewed from several perspectives in the past, but no prior treatment has examined the impact of natural product and natural product-based pesticides on the U.S. market, as a function of new active ingredient registrations with the Environmental Protection Agency (EPA). Thus, EPA registration details of new active ingredients for all conventional pesticide registrations and biopesticide registrations were compiled from the years 1997-2010. Conventional pesticide registrations and biopesticide registrations were examined both collectively and independently for all 277 new active ingredients (NAI) and subsequently categorized and sorted into four types: biological (B), natural product (NP), synthetic (S), and synthetic natural derived (SND). When examining conventional pesticides alone, the S category accounted for the majority of NAI registrations, with 78.0%, followed by SND with 14.7%, NP with 6.4%, and B with 0.9%. Biopesticides alone were dominated by NPs with 54.8%, followed by B with 44.6%, SND with 0.6%, and 0% for S. When examining conventional pesticides and biopesticides combined, NPs accounted for the majority of NAI registrations, with 35.7%, followed by S with 30.7%, B with 27.4%, and SND with 6.1%. Despite the common perception that natural products may not be the best sources for NAI as pesticides, when both conventional and biopesticides are examined collectively, and considering that NP, SND, and B all have origins from natural product research, it can be argued that their combined impact with the EPA from 1997 to 2010 accounted for 69.3% of all NAI registrations. PMID:22616957

Cantrell, Charles L; Dayan, Franck E; Duke, Stephen O

2012-06-22

43

Microbiological degradation of pesticides in yard waste composting.  

PubMed Central

Changes in public opinion and legislation have led to the general recognition that solid waste treatment practices must be changed. Solid-waste disposal by landfill is becoming increasingly expensive and regulated and no longer represents a long-term option in view of limited land space and environmental problems. Yard waste, a significant component of municipal solid waste, has previously not been separated from the municipal solid-waste stream. The treatment of municipal solid waste including yard waste must urgently be addressed because disposal via landfill will be prohibited by legislation. Separation of yard waste from municipal solid waste will be mandated in many localities, thus stressing the importance of scrutinizing current composting practices in treating grass clippings, leaves, and other yard residues. Yard waste poses a potential environmental health problem as a result of the widespread use of pesticides in lawn and tree care and the persistence of the residues of these chemicals in plant tissue. Yard waste containing pesticides may present a problem due to the recalcitrant and toxic nature of the pesticide molecules. Current composting processes are based on various modifications of either window systems or in-vessel systems. Both types of processes are ultimately dependent on microbial bioconversions of organic material to innocuous end products. The critical stage of the composting process is the thermophilic phase. The fate and mechanism of removal of pesticides in composting processes is largely unknown and in need of comprehensive analysis. PMID:1886519

Fogarty, A M; Tuovinen, O H

1991-01-01

44

Pesticides  

MedlinePLUS

... are not just insect killers. They also include chemicals to control weeds, rodents, mildew, germs, and more. Many household products contain pesticides. Pesticides can protect your health by killing germs, animals, or plants that could hurt you. However, they can also ...

45

Recording and reporting experimental uses of pesticide products  

E-print Network

Recording and reporting experimental uses of pesticide products Prepared 6/25/04 CALS Occupational & Environmental Health New York State Pesticide Product Registration Procedures (August, 1996) require that. These regulations put a difficult burden on Cornell applicators of experimental use pesticides*, who often make

Pawlowski, Wojtek

46

Pesticide Labeling: Unique Product Labeling1 Frederick M. Fishel2  

E-print Network

PI-110 Pesticide Labeling: Unique Product Labeling1 Frederick M. Fishel2 1. This document is PI-110, professor, Agronomy Department, and Director, Pesticide Information Office; Florida Cooperative Extension not signify our approval to the exclusion of other products of suitable composition. Use pesticides safely

Watson, Craig A.

47

A Study on the Environmental Degradation of Pesticides Azinphos Methyl and Parathion Methyl  

Microsoft Academic Search

The effect of environmental parameters (temperature and relative humidity) on the degradation rate of azinphos methyl and parathion methyl was studied. Proprietary emulsifiable concentrates were diluted and added to each of 90 glass Petri dishes for each pesticide and were left overnight to dry. Petri dishes were placed in 18 air-tight containers (9 for each pesticide) in which were created

Panagiotis E. Athanasopoulos; Nikolaos V. Kyriakidis; Panagiotis Stavropoulos

2004-01-01

48

ADSORPTION, MOVEMENT, AND BIOLOGICAL DEGRADATION OF LARGE CONCENTRATIONS OF SELECTED PESTICIDES IN SOILS  

EPA Science Inventory

Because of the importance of soil in biologically reducing the quantity and retarding the rate of pollutant movement into groundwater, this laboratory study was initiated to evaluate the adsorption, mobility, and degradation of large concentrations of the pesticide atrazine, meth...

49

Dependence of pesticide degradation on sorption: nonequilibrium model and application to soil reactors  

Microsoft Academic Search

The effect of sorption on degradation of the pesticide 2,4-dichlorophenoxyacetic acid (2,4-D) was studied in a soil amended with various amounts of activated carbon (AC). The relationship between sorption and decay of 2,4-D was analyzed using analytical solutions for equilibrium sorption and to a two-site nonequilibrium adsorption model coupled with two first-order degradation terms for the dissolved and sorbed pesticide,

Lei Guo; William A. Jury; Robert J. Wagenet; Markus Flury

2000-01-01

50

Application of zerovalent iron (Fe(0)) to enhance degradation of HCHs and DDX in soil from a former organochlorine pesticides manufacturing plant.  

PubMed

Remediation of pesticide-polluted soil is particularly challenging when pesticides in soil are aged and a mixture of pesticides is present. Application of zerovalent iron (Fe(0)) was investigated to accelerate the degradation of HCHs (alpha-, beta-, gamma- and delta-hexachlorocyclohexane) and DDX (DDT, DDE and DDD) in the soil from a former organochlorine pesticide manufacturing plant. Ultrasonic extraction was used extract the organochlorine pesticides from soil. The identification and quantification of organochlorine pesticides in the extracts were accomplished by gas chromatograph. The addition of Fe(0) facilitated the degradation of the beta-HCH isomer, but had little effect on the degradation of alpha-HCH, gamma-HCH and delta-HCH. Zerovalent iron significantly increased the degradation of p,p'-DDT and o,p'-DDT in soil, and the percentage degradation of p,p'-DDT and o,p'-DDT increased with increased Fe(0) concentration during the first period of incubation. However, the amount of p,p'-DDD, the main dechlorinated product of p,p'-DDT, basically kept increased except in the unamended soil. The addition of Fe(0) therefore did not increased the percent degradation of summation SigmaDDT (p,p'-DDT+p,p'-DDD+p,p'-DDE) markedly. PMID:20303568

Yang, Su-Cai; Lei, Mei; Chen, Tong-Bin; Li, Xiao-Yan; Liang, Qi; Ma, Chuang

2010-04-01

51

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...

52

Original article Pesticide residues in bee products collected from  

E-print Network

Original article Pesticide residues in bee products collected from cherry trees protected during by the method used. During fer- mentation of bee bread the conjugates are hydrolysed and free pesticides (Received 23 November 1998; revised 27 April 1999; accepted 7 June 1999) Abstract - Pesticide (vinclozolin

Paris-Sud XI, Université de

53

40 CFR 158.2160 - Microbial pesticides product performance data requirements.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Microbial pesticides product performance data requirements...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2160...

2011-07-01

54

40 CFR 158.2030 - Biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Biochemical pesticides product chemistry data requirements table...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides §...

2010-07-01

55

40 CFR 158.2030 - Biochemical pesticides product chemistry data requirements table.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Biochemical pesticides product chemistry data requirements table...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides §...

2011-07-01

56

40 CFR 158.2160 - Microbial pesticides product performance data requirements.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Microbial pesticides product performance data requirements...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2160...

2010-07-01

57

40 CFR 158.2120 - Microbial pesticides product analysis data requirements table.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Microbial pesticides product analysis data requirements table...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2120...

2010-07-01

58

40 CFR 158.2120 - Microbial pesticides product analysis data requirements table.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Microbial pesticides product analysis data requirements table...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2120...

2011-07-01

59

Calculation of pesticide degradation in decaying cotton gin trash.  

PubMed

Pesticide residues were measured in stockpiled cotton gin trash (CGT) over a 2-year period. Samples were analysed by GC/MS/MS and interpretation of the results was aided by the presence of DDE residues, remnant from prior DDT use. Fourteen pesticide residues from current agricultural practice were detected in CGT. Several of these, including indoxacarb, profenofos, chlorpyrifos, propargite, bifenthrin, ethion and cyhalothrin, were more persistent than expected on the basis of published data for soil dissipation. The results showed a complex pattern of pesticide residue decay over time because of the simultaneous decomposition of the CGT matrix. PMID:18651089

Crossan, Angus N; Kennedy, Ivan R

2008-10-01

60

In-package nonthermal plasma degradation of pesticides on fresh produce.  

PubMed

In-package nonthermal plasma (NTP) technology is a novel technology for the decontamination of foods and biological materials. This study presents the first report on the potential of the technology for the degradation of pesticide residues on fresh produce. A cocktail of pesticides, namely azoxystrobin, cyprodinil, fludioxonil and pyriproxyfen was tested on strawberries. The concentrations of these pesticides were monitored in priori and post-plasma treatment using GC-MS/MS. An applied voltage and time dependent degradation of the pesticides was observed for treatment voltages of 60, 70 and 80 kV and treatment durations ranging from 1 to 5 min, followed by 24h in-pack storage. The electrical characterisation revealed the operation of the discharge in a stable filamentary regime. The discharge was found to generate reactive oxygen and excited nitrogen species as observed by optical emission spectroscopy. PMID:24598029

Misra, N N; Pankaj, S K; Walsh, Tony; O'Regan, Finbarr; Bourke, Paula; Cullen, P J

2014-04-30

61

78 FR 75343 - Pesticide Products; Registration Applications for New Active Ingredients  

Federal Register 2010, 2011, 2012, 2013

...www.epa.gov/pesticides/regulating/registration-public-involvement...applications to register pesticide products containing...SB3872. Product type: Microbial insecticide. Proposed...ANT-03. Product type: Microbial insecticide. Proposed...Environmental protection, Pesticides and pest....

2013-12-11

62

9 CFR 318.16 - Pesticide chemicals and other residues in products.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Pesticide chemicals and other residues in products...OF PRODUCTS General § 318.16 Pesticide chemicals and other residues in products...Nonmeat ingredients. Residues of pesticide chemicals, food additives...

2011-01-01

63

9 CFR 318.16 - Pesticide chemicals and other residues in products.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Pesticide chemicals and other residues in products...OF PRODUCTS General § 318.16 Pesticide chemicals and other residues in products...Nonmeat ingredients. Residues of pesticide chemicals, food additives...

2010-01-01

64

Assessment of the PD-TOFMS Technique for Pesticide Adsorption and Degradation on `as-received' Treated Soil  

E-print Network

1 Assessment of the PD-TOFMS Technique for Pesticide Adsorption and Degradation on `as The assessment of the PD-TOFMS technique as a tool for direct characterization of pesticides adsorbed pesticides, namely norflurazon, malathion and oxyfluorfen, as well as deposits of these solutions onto

Paris-Sud XI, Université de

65

Degradation of pesticide mixture on modified matrix of a biopurification system with alternatives lignocellulosic wastes.  

PubMed

The biobed systems were designed to retain and to degrade pesticides through the properties of a biomixture composed of straw (ST), topsoil and peat (PT) 2:1:1 v/v. The ST is the main substrate in the biomixture, as it allows the proliferation of fungi that promotes pesticide degradation. The use of readily available components in the biomixture is an important aspect to build a biobed. Therefore, potential use of readily available wastes as barley husk (BH), sawdust (SW) and oat husk (OH), as total or partial substitutes of ST were tested in pesticide degradation studies. Metabolite formation and the biological activities were also evaluated. Biomixture composed of OH was highly efficient in pesticide degradation, with t˝ values of 28.6, 58.9 and 26.8 d for atrazine (ATZ), chlorpyrifos (CHL) and isoproturon (ISP). On the other hand, comparable for degrading capacities with the ST based biomixture were obtained with SW and BH, but only as partial replacement. Contrarily, high t˝ values (more than 100 d) were obtained in biomixtures with total substitution of ST by SW or BH. Metabolite formation was observed in all biomixtures tested, but without clear formation patterns. Moreover, high and stable biological activity was observed in the biomixtures composed of OH. Therefore, our results demonstrated that ST can be partial or totally replaced by OH in the biomixture allowing an efficient degradation of pesticide mixture. However, it is recommended that ST can be only partially replaced by BH and SW in the biomixture to allow efficient pesticide degradation. PMID:23746365

Urrutia, C; Rubilar, O; Tortella, G R; Diez, M C

2013-08-01

66

Pesticide Analysis of Bee and Bee Product Samples  

Microsoft Academic Search

Bee products possess therapeutic properties and are the source of many essential trace elements, which is why they are regarded as valuable food products. Honey bees may bring to the hive numerous contaminants deposited on the plants they visit, including pesticide without xenobiotics. The large-scale application of pesticides in agriculture and horticulture can lead to mass mortality among bees, and

?aneta Barga?ska; Jacek Namie?nik

2010-01-01

67

Integration of Solar Photocatalysis and Membrane Bioreactor for Pesticides Degradation  

Microsoft Academic Search

Wastewater containing recalcitrant contaminants as pesticides can be treated by a coupled system which consists of a solar photo-Fenton pretreatment followed by a biological oxidation process. Membrane bioreactor technology (MBR) is particularly suitable for advanced biological treatment of wastewater containing biorecalcitrant compounds and shows a variety of advantages that make it a good alternative to be coupled with photo-Fenton, especially

J. L. Casas López; A. Cabrera Reina; E. Ortega Gómez; M. M. Ballesteros Martín; S. Malato Rodríguez; J. A. Sánchez Pérez

2010-01-01

68

Photoelectrocatalytic degradation of high COD dipterex pesticide by using TiO2/Ni photo electrode.  

PubMed

A TiO2 thin film electrode deposited on porous nickel net (TiO2/Ni) was prepared by the sol-gel method, and the surface morphology, crystal structure features and the grain size were characterized by Field emission scan electron microscopy (FESEM) and X-ray diffraction (XRD). The photoelectrocatalytic system was set up using a UV high-pressure mercury lamp as the light source, TiO2 coated on foamed nickel as photo anode, Pt sheet as counter electrode and the pesticide dipterex in synthetic wastewater. Various factors that influence the photoelectrocatalytic decomposition of dipterex pesticide have been studied, such as degradation time, the type of electrolyte, current density, original pH value and different degradation methods. The prepared catalysts were employed to photoelectrocatalytically degrade the pesticide dipterex under UV irradiation, comparing the results with photocatalytic degradation and electrochemical oxidation. The results indicated that under the optimal conditions of 0.02 mol/L NaCl as the supporting electrolyte, current density = 2.5 mA/cm2, pH 6.0 and dipterex pesticide 40 mg/L, and reaction time 2 hr, dipterex chemical oxygen demand (COD) removal rate and organophosphorous conversion of up to 82.6% and 83.5% were achieved, respectively. The method of photoelectrocatalytic degradation is more efficient than photocatalysis and electrochemical oxidation. The possible roles of the electrolytes on the reactions and probable mechanisms were also discussed. PMID:23505884

Fang, Tao; Yang, Chao; Liao, Lixia

2012-01-01

69

78 FR 57388 - Product Cancellation Order for Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...registrants, of certain manufacturing use and end use pesticide...unit. Table 1--Manufacturing Use Product Cancellations...Ultimate Bug Candle. 83467-1...Kerslig Candle Light, 5807 Church...cancellation for the manufacturing products, listed...

2013-09-18

70

Estimating Pesticide Marginal Productivity of Apples Using Damage Control Econometrics  

Microsoft Academic Search

Summary Emp ?ic aJ studies of pesticide productivity have not been undertaken in )apan. This is mainly due to the difficulty of handling pesticides as a standard economic inpu t. Damage control agent such as pesti- cides increase the share of potential output that producers realize by reducing damage ?om natural causes. It di ?ers fundamentally ?om standard inputs. This

Naoki KON-YA

71

Pesticides.  

ERIC Educational Resources Information Center

This review is devoted to methods for the determination of residues of pesticides and some related industrial chemicals. Topics include: residue methods, sampling, chromatography, organochlorine pesticides, organophosphorus pesticides, carbamate insecticides, herbicides, fungicides, pyrethrins, fumigants, and related chemicals. (MVL)

Sherma, Joseph

1989-01-01

72

Effect of different soil textures on leaching potential and degradation of pesticides in biobeds.  

PubMed

Biobeds can be used to intercept pesticide-contaminated runoff from the mixing/washdown area, creating optimum conditions for sorption and biodegradation such that the amount of pesticide reaching adjacent water bodies is significantly reduced. The biobed is built on the farm using locally available materials, which include, straw, compost, and topsoil. The topsoil acts as the inoculum for the system and is likely to vary in terms of its physical, chemical, and microbiological characteristics from one farm to another. This study therefore investigated the effects of using different soil types on the degradation and leaching potential from biobeds. Three contrasting topsoils were investigated. Leaching studies were performed using isoproturon, dimethoate, and mecoprop-P, which were applied at simulated disposal rates to 1.5 m deep biobeds. Annual average concentrations were similar for each soil type with leaching losses of even the most mobile (Koc = 12-25) pesticide <1.64% of the applied dose. Greater than 98% of the retained pesticides were degraded in all matrices. Degradation studies investigated the persistence of individual pesticides and pesticide mixtures in the different matrices. DT50 values for isoproturon, chlorothalonil, mecoprop-P, and metsulfuron-methyl applied at 4 times the maximum approved rate were similar across the biomix types and were all less than or equal to reported DT50 values for soil treated at approved rates. When applied as a mixture, DT50 values in each biomix increased, indicating that interactions between pesticides are possible. However, DT90 values of <167 days were obtained in all circumstances, indicating a negligible risk of accumulation. Studies therefore indicate that substrate will have little impact on biobed performance so it should be possible to use local soils in the construction process. PMID:15373405

Fogg, Paul; Boxall, Alistair B A; Walker, Allan; Jukes, Andrew

2004-09-01

73

Degradation of pesticides chlorpyrifos, cypermethrin and chlorothalonil in aqueous solution by TiO2 photocatalysis.  

PubMed

Degradation of pesticides chlorpyrifos, cypermethrin and chlorothalonil in aqueous solution by TiO2 photocatalysis under UVA (365 nm) irradiation was examined. Enhancement of degradation and improvement in biodegradability index (BOD5/COD ratio) by H2O2 addition were also evaluated. UVA irradiation per se produced insignificant degradation of the pesticides. In UV/TiO2 photocatalysis (TiO2 1.5 g L(-1), pH 6 and 300 min irradiation), COD and TOC removal were 25.95 and 8.45%, respectively. In UV/TiO2/H2O2 photocatalysis (TiO2 1.5 g L(-1), H2O2 100 mg L(-1), pH 6 and 300 min irradiation), COD and TOC removal were 53.62 and 21.54%, respectively and biodegradability index improved to 0.26. Ammonia-nitrogen (NH3-N) decreased from 22 to 7.8 mg L(-1) and nitrate-nitrogen (NO3(-)-N) increased from 0.7 to 13.8 mg L(-1) in 300 min, indicating mineralization. Photocatalytic degradation followed pseudo-first order kinetics with rate constant (k) of 0.0025 and 0.0008 min(-1) for COD and TOC removal, respectively. FTIR spectra indicated degradation of the organic bonds of the pesticides. UV/TiO2/H2O2 photocatalysis is effective in degradation of pesticides chlorpyrifos, cypermethrin and chlorothalonil in aqueous solution. UV/TiO2/H2O2 photocatalysis may be applied as pretreatment of a chlorpyrifos, cypermethrin and chlorothalonil pesticide wastewater at pH 6, for biological treatment. PMID:24076516

Affam, Augustine Chioma; Chaudhuri, Malay

2013-11-30

74

40 CFR 152.15 - Pesticide products required to be registered.  

Code of Federal Regulations, 2010 CFR

... 23 2010-07-01 2010-07-01 false Pesticide products required to be registered. 152.15...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES...

2010-07-01

75

40 CFR 165.67 - Registrants who distribute or sell pesticide products to refillers for repackaging.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Registrants who distribute or sell pesticide products to refillers for repackaging. 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2011-07-01

76

40 CFR 165.65 - Registrants who distribute or sell pesticide products in refillable containers.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Registrants who distribute or sell pesticide products in refillable containers. 165.65...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2011-07-01

77

40 CFR 165.65 - Registrants who distribute or sell pesticide products in refillable containers.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Registrants who distribute or sell pesticide products in refillable containers. 165.65...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2010-07-01

78

40 CFR 152.15 - Pesticide products required to be registered.  

Code of Federal Regulations, 2011 CFR

... 24 2011-07-01 2011-07-01 false Pesticide products required to be registered. 152.15...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES...

2011-07-01

79

40 CFR 165.67 - Registrants who distribute or sell pesticide products to refillers for repackaging.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Registrants who distribute or sell pesticide products to refillers for repackaging. 165...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE MANAGEMENT AND DISPOSAL Standards for...

2010-07-01

80

75 FR 74713 - Product Cancellation Order for Certain Pesticide Registrations; Correction  

Federal Register 2010, 2011, 2012, 2013

...document is being issued to rescind the cancellation of Sergeant's Pet Care Products' pesticide product, EPA Reg. No. 2517-79...notice do? This notice rescinds the cancellation of Sergeant's Pet Care Products' pesticide product, EPA Reg. No....

2010-12-01

81

Page 1 of 4 Training and Exam Options for Pesticide Applicators of Soil Fumigant Products  

E-print Network

Page 1 of 4 Training and Exam Options for Pesticide Applicators of Soil Fumigant Products Information for Pesticide State Lead Agencies (SLAs) September 2011 It is the year 2012 and a pesticide. The pesticide applicator is already certified and has met all other requirements to use restricteduse soil

82

Solar photocatalytic degradation of some hazardous water-soluble pesticides at pilot-plant scale.  

PubMed

The technical feasibility and performance of photocatalytic degradation of six water-soluble pesticides (cymoxanil, methomyl, oxamyl, dimethoate, pyrimethanil and telone) have been studied at pilot-plant scale in two well-defined systems which are of special interest because natural solar UV light can be used: heterogeneous photocatalysis with titanium dioxide and homogeneous photocatalysis by photo-Fenton. TiO(2) photocatalysis tests were performed in a 35L solar pilot plant with three Compound Parabolic Collectors (CPCs) under natural illumination and a 75L solar pilot plant with four CPC units was used for homogeneous photocatalysis tests. The initial pesticide concentration studied was 50 mg L(-1) and the catalyst concentrations employed were 200 mg L(-1) of TiO(2) and 20 mg L(-1) of iron. Both toxicity (Vibrio fischeri, Biofix) and biodegradability (Zahn-Wellens test) of the initial pesticide solutions were also measured. Total disappearance of the parent compounds and nearly complete mineralization were attained with all pesticides tested. Treatment time, hydrogen peroxide consumption and release of heteroatoms are discussed. PMID:16839679

Oller, I; Gernjak, W; Maldonado, M I; Pérez-Estrada, L A; Sánchez-Pérez, J A; Malato, S

2006-12-01

83

Catalytic strategy for efficient degradation of nitroaromatic pesticides by using gold nanoflower.  

PubMed

In this contribution, we report a new type of Au nanoflower-based nitroaromatic pesticide degradation platform that is fast, efficient, and simple. We found a straightforward, economically viable, and "green" approach for the synthesis and stabilization of relatively monodisperse Au nanoflowers by using nontoxic chemical of hydroxylamine (NH2OH) without stabilizer and the adjustment of the pH environment. This experiment shows that these Au nanoflowers function as effective catalyst for the reduction of pendimethalin in the presence of NaBH4 (otherwise unfeasible if NaBH4 is the only agent employed), which was reflected by the UV/vis spectra of the catalytic reaction kinetics. Importantly, the novel degradation platform could be put in use in two different practical soil samples with satisfactory results under laboratory conditions. To demonstrate the feasibility and universality of our design, two other nitroaromatic pesticides, trifluralin, and p-nitrophenol, were selected and were successfully degraded using this degradation platform. PMID:25329810

Mao, Kang; Chen, Yinran; Wu, Zitong; Zhou, Xiaodong; Shen, Aiguo; Hu, Jiming

2014-11-01

84

Pesticide nonextractable residue formation in soil: insights from inverse modeling of degradation time series.  

PubMed

Formation of soil nonextractable residues (NER) is central to the fate and persistence of pesticides. To investigate pools and extent of NER formation, an established inverse modeling approach for pesticide soil degradation time series was evaluated with a Monte Carlo Markov Chain (MCMC) sampling procedure. It was found that only half of 73 pesticide degradation time series from a homogeneous soil source allowed for well-behaved identification of kinetic parameters with a four-pool model containing a parent compound, a metabolite, a volatile, and a NER pool. A subsequent simulation indeed confirmed distinct parameter combinations of low identifiability. Taking the resulting uncertainties into account, several conclusions regarding NER formation and its impact on persistence assessment could nonetheless be drawn. First, rate constants for transformation of parent compounds to metabolites were correlated to those for transformation of parent compounds to NER, leading to degradation half-lives (DegT50) typically not being larger than disappearance half-lives (DT50) by more than a factor of 2. Second, estimated rate constants were used to evaluate NER formation over time. This showed that NER formation, particularly through the metabolite pool, may be grossly underestimated when using standard incubation periods. It further showed that amounts and uncertainties in (i) total NER, (ii) NER formed from the parent pool, and (iii) NER formed from the metabolite pool vary considerably among data sets at t??, with no clear dominance between (ii) and (iii). However, compounds containing aromatic amine moieties were found to form significantly more total NER when extrapolating to t?? than the other compounds studied. Overall, our study stresses the general need for assessing uncertainties, identifiability issues, and resulting biases when using inverse modeling of degradation time series for evaluating persistence and NER formation. PMID:22891938

Loos, Martin; Krauss, Martin; Fenner, Kathrin

2012-09-18

85

Syntheses of Potential Degradation Products of Phenylephrine in OTC Products  

Microsoft Academic Search

Compound 1 and 2 are potential major degradants in over the counter (OTC) products containing phenylephrine HCl and dexbrompheniramine maleate or chlorpheniramine maleate. Compound 2 matches the unknown peak in the solution of stressed active and excipient and thus was identified as the correct degradation product. Whether the degradation product is racemic or chiral is not known. This article describes

T.-M. Chan; Jianshe Kong; Paul McNamara; Jesse K. Wong

2008-01-01

86

Multi-residue method for the analysis of 101 pesticides and their degradates in food and water samples by liquid chromatography\\/time-of-flight mass spectrometry  

Microsoft Academic Search

A comprehensive multi-residue method for the chromatographic separation and accurate mass identification of 101 pesticides and their degradation products using liquid chromatography\\/time-of-flight mass spectrometry (LC\\/TOF-MS) is reported here. Several classes of compounds belonging to different chemical families (triazines, organophosphorous, carbamates, phenylureas, neonicotinoids, etc.) were carefully chosen to cover a wide range of applications in the environmental field. Excellent chromatographic separation

Imma Ferrer; E. Michael Thurman

2007-01-01

87

78 FR 4073 - Labeling of Pesticide Products and Devices for Export; Clarification of Requirements  

Federal Register 2010, 2011, 2012, 2013

...FRL-9360-8] RIN 2070-AJ53 Labeling of Pesticide Products and Devices for Export; Clarification...revising the regulations on the labeling of pesticide products and devices intended solely...that people who transfer unregistered pesticide products between registered...

2013-01-18

88

[Validation study on a multi-residue analysis of pesticides in agricultural products by using phosphoric acid treatment and GC-MS/MS].  

PubMed

A rapid method for multi-residue determination of pesticides in agricultural products was validated. The sample was cut into pieces and placed into a mixer cup containing half weight amount of 10% phosphoric acid in order to suppress degradation of easily degraded pesticides, represented by captan, and then homogenized. Pesticides in the phosphoric acid-treated sample were extracted with acetonitrile using a homogenizer, followed by salting out with anhydrous magnesium sulfate and sodium chloride. The extract was cleaned up on a C18 and graphite carbon black/PSA mini-cartridge column. Some pesticides gave tailing peaks, but these peaks became sharp and symmetrical when polyethylene glycol (PEG) 300 was added to the test solution. Recovery tests were performed on nine kinds of agricultural products (brown rice, soybean, spinach, cabbage, potato, orange, apple, strawberry, and Japanese pear) fortified with 170 pesticides at 0.01 and 0.1 ?g/g. Each concentration of pesticide residue was extracted from 2 samples on 5 separate days. The trueness of the method for 147-164 pesticides in each sample was 70-120% with satisfactory repeatability and within-run reproducibility. This method is expected to useful for multi-residue analysis of pesticides in agricultural products. PMID:25212821

Makabe, Yuhki; Takahashi, Hiroshi; Enomoto, Tomoko; Aikawa, Takehiko

2014-01-01

89

Pesticides  

MedlinePLUS

... of activity. This means that they can have toxic effects in humans as well as in the ... Depending on the particular pesticide, they can be toxic if swallowed, inhaled, or have direct contact with ...

90

Exposure Assessment for Pesticide Intake from Multiple Food Products : A Bayesian  

E-print Network

Exposure Assessment for Pesticide Intake from Multiple Food Products : A Bayesian Latent-Variable Approach May 1, 2008 1 #12;1 Abstract Pesticide risk assessment for food products involves combining information from consumption and concentration data sets to estimate a distribution for the pesticide intake

Theobald, Chris

91

Sorption and degradation of chlorophenols, nitrophenols and organophosphorus pesticides in the subsoil under landfills — laboratory studies  

NASA Astrophysics Data System (ADS)

Landfills and old industrial plant sites have been identified in an increasing number of cases as point sources of groundwater pollution, dissipating a wide range of industrial chemicals and pesticides. To study the fate of co-disposed chemicals in the subsoil of landfills, anaerobic soil columns loaded with anaerobic leachate from a municipal landfill were set up. The leachate was spiked with eleven compounds representing three groups of chemicals: chlorophenols, nitrophenols and organophosphates. Two subsoils were used in the study. The columns were maintained at Danish groundwater temperature (8-10°C), and were run for a period of 10 months. Analysis of the influent leachate concentrations of the spiked compounds showed that the concentrations were constant during the entire experimental period. Many of the compounds showed delayed breakthrough (compared to chloride breakthrough) in both soils, followed by a constant effluent concentration ratio of less than unity indicating that degradation was occuring. The velocities for the chloro- and nitrophenols were in the range of 10-100% of the water velocity in the two subsoils. The distribution coefficient for the specific phenol, the acidity and the pH of the soil apparently governed the retardation of the phenolic compounds. Degradation of most of the phenols was observed with half-like values of 30-150 days. The four organophosphorus pesticides, Dimethoate ®, Malathion ®, Sulfotep ® and Fenitrothion ®, showed relative velocities from < 10% to ? 100%. Malathion ® and Sulfotep ® were degraded with half-life values of 10-20 days, while Dimethoate ® was not significantly degraded in the two soil columns. Fenitrothion ® did not appear in the effluent from the columns within the experimental period of time, probably due to high retardation.

Kjeldsen, Peter; Kjřlholt, Jesper; Schultz, Birgit; Christensen, Thomas H.; Tjell, Jens Christian

1990-09-01

92

40 CFR 152.8 - Products that are not pesticides because they are not for use against pests.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Products that are not pesticides because they are not for use against pests. ...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES...

2010-07-01

93

40 CFR 152.8 - Products that are not pesticides because they are not for use against pests.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Products that are not pesticides because they are not for use against pests. ...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES...

2011-07-01

94

76 FR 63298 - Pesticide Products; Registration Applications  

Federal Register 2010, 2011, 2012, 2013

...use product. (Ann Sibold; (703) 305-6502; sibold.ann@epa.gov; EPA-HQ-2011-0769) 4. File symbol: 73049-UTI. Applicant: Valent BioSciences Corporation, 870 Technology Way, Libertyville, IL 60048. Product name: VBC-60219...

2011-10-12

95

78 FR 11879 - Product Cancellation Order for Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...advocates; the chemical industry; pesticide users; and members of the...distribution, or use of pesticides. Since others also may be...regulations.gov or at the Office of Pesticide Programs Regulatory Public...Bee, Wasp & Hornet...

2013-02-20

96

Monitoring of Pesticide Residues in Apples from Slovakia for Baby Food Production  

Microsoft Academic Search

DÖMÖTÖROVÁ M., HERCEGOVÁ A., MATISOVÁ E. (2006): Monitoring of pesticide residues in apples from Slovakia for baby food production. Czech J. Food Sci., 24: 84-92. There is a basic lack of information about the presence of pesticide residues in apples obtained from farms in Slovakia collaborating with baby food producer. Residues of several pesticides (widely used for the protection on

MILENA DÖMÖTÖROVÁ; ANDREA HERCEGOVÁ; EVA MATISOVÁ

2006-01-01

97

75 FR 24694 - Pesticide Products; Registration Applications  

Federal Register 2010, 2011, 2012, 2013

...150, Cary, NC 27513. Product name: Kasugamycin Technical. Active ingredient: Kasugamycin hydrochloride at 85.8%. Proposed classification...name: Kasumin 2L. Active ingredient: Kasugamycin hydrochloride at 2.3%. Proposed...

2010-05-05

98

Partial degradation of five pesticides and an industrial pollutant by ozonation in a pilot-plant scale reactor.  

PubMed

Aqueous solutions of a mixture of several pesticides (alachlor, atrazine, chlorfenvinphos, diuron and isoproturon), considered PS (priority substances) by the European Commission, and an intermediate product of the pharmaceutical industry (alpha-methylphenylglycine, MPG) chosen as a model industrial pollutant, have been degraded at pilot-plant scale using ozonation. This study is part of a large research project [CADOX Project, A Coupled Advanced Oxidation-Biological Process for Recycling of Industrial Wastewater Containing Persistent Organic Contaminants, Contract No.: EVK1-CT-2002-00122, European Commission, http://www.psa.es/webeng/projects/cadox/index.html] founded by the European Union that inquires into the potential coupling between chemical and biological oxidations for the removal of toxic or non-biodegradable contaminants from water. The evolution of pollutant concentration, TOC mineralization, generation of inorganic species and consumption of O3 have been followed in order to visualize the chemical treatment effectiveness. Although complete mineralization is hard to accomplish, and large amounts of the oxidant are required to lower the organic content of the solutions, the possibility of ozonation cannot be ruled out if partial degradation is the final goal wanted. In this sense, Zahn-Wellens biodegradability tests of the ozonated MPG solutions have been performed, and the possibility of a further coupling with a secondary biological treatment for complete organic removal is envisaged. PMID:16822610

Maldonado, M I; Malato, S; Pérez-Estrada, L A; Gernjak, W; Oller, I; Doménech, Xavier; Peral, José

2006-11-16

99

Model-based estimation of pesticides and transformation products and their export pathways in a headwater catchment  

NASA Astrophysics Data System (ADS)

Pesticides applied onto agricultural fields are frequently found in adjacent rivers. To what extent and along which pathways they are transported is influenced by intrinsic pesticide properties such as sorption and degradation. In the environment, incomplete degradation of pesticides leads to the formation of transformation products (TPs), which may differ from the parent compounds regarding their intrinsic fate characteristics. Thus, the export processes of TPs in catchments and streams may also be different. In order to test this hypothesis, we extended a distributed hydrological model by the fate and behaviour of pesticides and transformation products and applied it to a small, well-monitored headwater catchment in Switzerland. The successful model evaluation of three pesticides and their TPs at three sampling locations in the catchment enabled us to estimate the quantity of contributing processes for pollutant export. Since all TPs were more mobile than their parent compounds (PCs), they exhibited larger fractions of export via subsurface pathways. However, besides freshly applied pesticides, subsurface export was found to be influenced by residues of former applications. Export along preferential flow pathways was less dependent on substance fate characteristics than soil matrix export, but total soil water flow to tile drains increased more due to preferential flow for stronger sorbing substances. Our results indicate that runoff generation by matrix flow to tile drains gained importance towards the end of the modelling period whereas the contributions from fast surface runoff and preferential flow decreased. Accordingly, TPs were to a large extent exported under different hydrological conditions than their PCs, due to their delayed formation and longer half-lives. Thus, not only their different intrinsic characteristics but also their delayed formation could be responsible for the fact that TPs generally took different pathways than their PCs. We suggest that these results should be considered in risk assessment for the export of agricultural chemicals to adjacent rivers and that models should be extended to include both PCs and TPs.

Gassmann, M.; Stamm, C.; Olsson, O.; Lange, J.; Kümmerer, K.; Weiler, M.

2013-07-01

100

An efficient and novel porous nanosilica supported TiO2 photocatalyst for pesticide degradation using solar light.  

PubMed

A latex polymer of styrene-acrylic acid emulsion is used as a template for the synthesis of novel porous nanosilica (PNS) material. TiO(2) is dispersed over PNS by solid state dispersion and the composite materials are characterized by XRD, nitrogen adsorption-desorption isotherms, SEM and TEM measurements. The photocatalytic activities of the composite TiO(2)/PNS catalysts are evaluated for degradation of isoproturon pesticide in water with different parameters under solar light. Furthermore, commercial pesticide solutions containing imidacloprid and phosphamidon were also degraded successfully with the composite system using the same developed conditions for isoproturon degradation. The 5 wt% TiO(2)/PNS is found to be active in the present investigation. PMID:19596511

Phanikrishna Sharma, Mangalampalli V; Sadanandam, Gullapelli; Ratnamala, Ajjarapu; Durga Kumari, Valluri; Subrahmanyam, Machiraju

2009-11-15

101

Identification and ecotoxicity of degradation products of chloroacetamide herbicides from UV-treatment of water.  

PubMed

The widespread occurrence of chlorinated herbicides and their degradation products in the aquatic environment raises health and environmental concerns. As a consequence pesticides, and to a lesser degree their degradation products, are monitored by authorities both in surface waters and drinking waters. In this study the formation of degradation products from ultraviolet (UV) treatment of the three chloroacetamide herbicides acetochlor, alachlor and metolachlor and their biological effects were investigated. UV treatment is mainly used for disinfection in water and wastewater treatments. First, the chemical structures of the main UV-degradation products were identified using gas chromatography coupled with mass spectrometry and liquid chromatography-mass spectrometry. The main transformation reactions were dechlorination, mono- and multi-hydroxylation and cyclizations. The ecotoxicity of the mixed photoproducts formed by UV-treatment until 90% of the original pesticide was converted was compared to the toxicity of chloroacetamides using the green alga Pseudokirchneriella subcapitata, the crustacean Daphnia magna and the marine bacteria Vibrio fischeri as test organisms. UV-treatment of alachlor and metolachlor increased the toxicity compared to the parent compounds while an equal toxicity was found for photolysis products of acetochlor. This suggests that toxic photodegradation products are generated from chloroacetamides under UV-treatment. An important perspective of this finding is that the photolysis products are at least as toxic as the parent compounds. PMID:23707723

Souissi, Yasmine; Bouchonnet, Stéphane; Bourcier, Sophie; Kusk, Kresten Ole; Sablier, Michel; Andersen, Henrik Rasmus

2013-08-01

102

Canadian Consumer's Willingness-To-Pay For Pesticide Free Food Products: An Ordered Probit Analysist1  

Microsoft Academic Search

A new crop production system has emerged in western Canada. Pesticide Free ProductionTM (PFPTM) emphasizes reduced pesticide use in conjunction with increased reliance on producer knowledge of agronomic practices that mitigate weed, insect and disease pressure. A contingent valuation survey was undertaken to determine if Canadian consumers would pay a premium for PFPTM food products. Over 65 percent of respondents

J. A. L. Cranfield; Erik Magnusson

103

Diluent Degradation Products in the Purex Solvent  

Microsoft Academic Search

A number of laboratory tests were conducted in which various impurities, known to be present in degraded Purex solvent, were injected into fresh solvent samples and the effects of these impurities tested in an operating miniature pulse column and in batch contactors. Common fission product elements which interfere in the Purex process were spiked with radiotracers and added to the

J. C. Neace

1983-01-01

104

Single-Step Production of a Recyclable Nanobiocatalyst for Organophosphate Pesticides Biodegradation Using Functionalized Bacterial Magnetosomes  

PubMed Central

Enzymes are versatile catalysts in laboratories and on an industrial scale; improving their immobilization would be beneficial to broadening their applicability and ensuring their (re)use. Lipid-coated nano-magnets produced by magnetotactic bacteria are suitable for a universally applicable single-step method of enzyme immobilization. By genetically functionalizing the membrane surrounding these magnetite particles with a phosphohydrolase, we engineered an easy-to-purify, robust and recyclable biocatalyst to degrade ethyl-paraoxon, a commonly used pesticide. For this, we genetically fused the opd gene from Flavobacterium sp. ATCC 27551 encoding a paraoxonase to mamC, an abundant protein of the magnetosome membrane in Magnetospirillum magneticum AMB-1. The MamC protein acts as an anchor for the paraoxonase to the magnetosome surface, thus producing magnetic nanoparticles displaying phosphohydrolase activity. Magnetosomes functionalized with Opd were easily recovered from genetically modified AMB-1 cells: after cellular disruption with a French press, the magnetic nanoparticles are purified using a commercially available magnetic separation system. The catalytic properties of the immobilized Opd were measured on ethyl-paraoxon hydrolysis: they are comparable with the purified enzyme, with Km (and kcat) values of 58 µM (and 178 s?1) and 43 µM (and 314 s?1) for the immobilized and purified enzyme respectively. The Opd, a metalloenzyme requiring a zinc cofactor, is thus properly matured in AMB-1. The recycling of the functionalized magnetosomes was investigated and their catalytic activity proved to be stable over repeated use for pesticide degradation. In this study, we demonstrate the easy production of functionalized magnetic nanoparticles with suitably genetically modified magnetotactic bacteria that are efficient as a reusable nanobiocatalyst for pesticides bioremediation in contaminated effluents. PMID:21738665

Ginet, Nicolas; Pardoux, Romain; Adryanczyk, Géraldine; Garcia, Daniel; Brutesco, Catherine; Pignol, David

2011-01-01

105

78 FR 72879 - Product Cancellation Order for Certain Pesticide Registrations; Correction  

Federal Register 2010, 2011, 2012, 2013

...FR 57850) (FRL-9396-3), concerning the product cancellation of several pesticide products, including the following McLaughlin Gormley King Co.'s product registrations: D-trans Allethrin 90% Concentrate (EPA Reg. No. 001021-01060),...

2013-12-04

106

Influence of parameters on the heterogeneous photocatalytic degradation of pesticides and phenolic contaminants in wastewater: A short review  

Microsoft Academic Search

In recent years, the application of heterogeneous photocatalytic water purification processes has gained wide attention due to its effectiveness in degrading and mineralizing the recalcitrant organic compounds as well as the possibility of utilizing the solar UV and visible-light spectrum. This paper aims to review and summarize the recent works on the titanium dioxide (TiO2) photocatalytic oxidation of pesticides and

Saber Ahmed; M. G. Rasul; R. Brown; M. A. Hashib

2011-01-01

107

Common Pesticide Questions  

MedlinePLUS

... About Your Pest Control Your Pest Integrated Pest Management Pesticide Ingredients Active Ingredients Other/Inert Ingredients Pesticide Products Low-Risk Pesticides Organic Pesticide Ingredients Regulations State Federal International Environment Air Water Soil Wildlife Plants Emergency Human ...

108

Organic Pesticide Ingredients  

MedlinePLUS

... About Your Pest Control Your Pest Integrated Pest Management Pesticide Ingredients Active Ingredients Other/Inert Ingredients Pesticide Products Low-Risk Pesticides Organic Pesticide Ingredients Regulations State Federal International Environment Air Water Soil Wildlife Plants Emergency Human ...

109

Pesticide Fact Sheets  

MedlinePLUS

... About Your Pest Control Your Pest Integrated Pest Management Pesticide Ingredients Active Ingredients Other/Inert Ingredients Pesticide Products Low-Risk Pesticides Organic Pesticide Ingredients Regulations State Federal International Environment Air Water Soil Wildlife Plants Emergency Human ...

110

Productivity, pesticides, and management of the Peregrine Falcon in Arizona  

USGS Publications Warehouse

In the decade since research commenced with the Peregrine in Arizona, over 60 sites have been identified which historically or presently are occupied by breeding pairs. Productivity was determined for about 120 breeding attempts from 1975-85. Almost all sites, for which productivity information is available for two or more years, have hatched young. Average values for fledging success were ca. 1.4 young/attempt for all active sites and ca. 2.3 young/attempt for successful sites. Eggshell thickness values were highly varied, but few samples reflect thinning sufficient to cause reproductive failure, and the population appears to be increasing slightly. Management practices which can further benefit the falcon include: controlling pesticide use, habitat protection, and information management.

Ellis, D.H.

1985-01-01

111

Inoculation with a mixed degrading culture improves the pesticide removal of an on-farm biopurification system.  

PubMed

To investigate whether the pesticide removal in on-farm biopurification systems (BPS) filled with two different types of substrata (biomix and plastic carriers) is affected by inoculation with a pesticide-degrading strain or mixed culture, lab-scale BPS used to treat chloropropham point source contaminations were bioaugmented with either a specialized chloropropham-degrading strain or a chloropropham-degrading enrichment culture. Application of both inoculum types leads to an accelerated degradation activity in the columns filled with plastic carriers. For both substratum types, inoculation with the mixed culture resulted in a lower breakthrough of the toxic intermediate 3-chloroaniline at high hydraulic loads, compared to inoculation with the pure isolate and no inoculation. This study suggests that the use of plastic carrier materials could be a proficient alternative to the use of a conventional biomix as a substratum in on-farm BPS and that inoculation with a mixed degrading culture can reduce the leaching of more mobile toxic intermediates. PMID:23708426

Verhagen, Pieter; De Gelder, Leen; Boon, Nico

2013-10-01

112

Assessment of model uncertainty during the river export modelling of pesticides and transformation products  

NASA Astrophysics Data System (ADS)

The modelling of organic pollutants in the environment is burdened by a load of uncertainties. Not only parameter values are uncertain but often also the mass and timing of pesticide application. By introducing transformation products (TPs) into modelling, further uncertainty coming from the dependence of these substances on their parent compounds and the introduction of new model parameters are likely. The purpose of this study was the investigation of the behaviour of a parsimonious catchment scale model for the assessment of river concentrations of the insecticide Chlorpyrifos (CP) and two of its TPs, Chlorpyrifos Oxon (CPO) and 3,5,6-trichloro-2-pyridinol (TCP) under the influence of uncertain input parameter values. Especially parameter uncertainty and pesticide application uncertainty were investigated by Global Sensitivity Analysis (GSA) and the Generalized Likelihood Uncertainty Estimation (GLUE) method, based on Monte-Carlo sampling. GSA revealed that half-lives and sorption parameters as well as half-lives and transformation parameters were correlated to each other. This means, that the concepts of modelling sorption and degradation/transformation were correlated. Thus, it may be difficult in modelling studies to optimize parameter values for these modules. Furthermore, we could show that erroneous pesticide application mass and timing were compensated during Monte-Carlo sampling by changing the half-life of CP. However, the introduction of TCP into the calculation of the objective function was able to enhance identifiability of pesticide application mass. The GLUE analysis showed that CP and TCP were modelled successfully, but CPO modelling failed with high uncertainty and insensitive parameters. We assumed a structural error of the model which was especially important for CPO assessment. This shows that there is the possibility that a chemical and some of its TPs can be modelled successfully by a specific model structure, but for other TPs, the model structure may not be suitable. Concluding, this study confirmed that the introduction of TPs into pesticide fate and export modelling from hydrological catchments amplifies parameter uncertainty and model structure uncertainty.

Gassmann, Matthias; Olsson, Oliver; Kümmerer, Klaus

2013-04-01

113

The Pesticide Action Network Pesticide Database  

NSDL National Science Digital Library

The Pesticide Action Network Pesticide Database, maintained by the Pesticide Action Network of North America, provides up-to-date information for those working with or researching pesticides. The site lets users search by chemical name, chemical abstracts service (CAS) number, trade name, or US EPA product registration number to retrieve a selected pesticide's active ingredients, breakdown products, and other chemicals used in it. Also available is California specific pesticide information, toxicity and regulation information, nontoxic alternatives to pesticides, and more.

2000-01-01

114

Bioremediation of single and mixture of pesticide-contaminated soils by mixed pesticide-enriched cultures.  

PubMed

In the present study, degradation efficiencies for individual as well as mixed pesticide in different Indian soils, by mixed pesticide-enriched cultures, were evaluated under submerged and unsaturated conditions, Lindane (L), methyl parathion (MP), carbofuran (C), and a mixture of L, MP, and C were used in the study. For all the various conditions considered, methyl parathion degradation was the maximum and lindane degradation was the minimum. The degradation kinetics of the pesticides in sandy, clayey, compost, and red soils by various microbial isolates were studied. It was observed that adsorption was maximum and degradation of pesticides was minimum in compost soil. The degradation efficiencies of pesticides in liquid phase associated with soil sediment were less than those under the normal liquid phase conditions as leaching of pesticides from soil phase was continuous. Pesticide degradation was more in submerged soils compared to that in unsaturated soils. The degradation by-products of individual and mixed pesticides in liquid, unsaturated, and submerged soils were identified. Different metabolites were produced under submerged and unsaturated conditions. PMID:21424248

Rama Krishna, K; Philip, Ligy

2011-08-01

115

Study on effects of temperature, moisture and pH in degradation and degradation kinetics of aldrin, endosulfan, lindane pesticides during full-scale continuous rotary drum composting.  

PubMed

Study focused on effects of temperature, moisture and pH on degradation and degradation kinetics of aldrin, endosulfan (?), endosulfan (?) and lindane during vegetable waste composting using full-scale continuous rotary drum composter (FSCRDC). Extraction, concentration and quantification of pesticides were made from waste material at different stages by ultra-sonification, silica gel column and GC-MS analysis. Removal efficiency of aldrin, endosulfan ?, endosulfan ? and lindane was found 85.67%, 84.95%, 83.20% and 81.36% respectively due to optimum temperature, moisture, pH and enhanced microbial activity. Maximum temperature in inlet zone was found 60-65°C which is most suitable for complex microbial population. After feeding and turning in inlet zone, temperature reduced to 38°C from 60 to 65°C and regained it within 7-8h, and pH reduced to 5.3±0.2 from 7.5±0.3 in 4h and regained it in 10h. Heterotrophic bacteria Bacillus sp., Pseudomonas sp. and Lactobacillus sp. also decreased from 4.4×10(3) to 7.80×10(2)CFU g(-1) in 2 h due to gradual variation in temperature and pH. No significant temperature change was found in middle and outlet zones during feeding and turning. Degradation of pesticides was observed as first order kinetics and half-life of aldrin, endosulfan ?, endosulfan ? and lindane was reduced to 25.54, 18.43, 18.43 and 27.43 d from 1095, 60, 270 and 160 d respectively. Thus, the observations in contrast of removal and degradation kinetics of organochlorine pesticides residues in vegetable waste though full-scale rotary drum composting proved it the best suited technique. PMID:24468112

Ali, Muntjeer; Kazmi, A A; Ahmed, Naseem

2014-05-01

116

A survey for small animal veterinarians regarding flea and tick control pesticide products  

PubMed Central

The Canadian Veterinary Medical Association administered a survey to capture the clinical experiences of small animal veterinarians regarding adverse effects observed in cats and dogs following the use of flea and tick control pesticide products. Results of this survey are discussed and compared with pesticide incident reports collected by Health Canada. PMID:22467961

Turner, Vanessa; Chaffey, Cheryl; Ferrao, Patricia

2011-01-01

117

A survey for small animal veterinarians regarding flea and tick control pesticide products.  

PubMed

The Canadian Veterinary Medical Association administered a survey to capture the clinical experiences of small animal veterinarians regarding adverse effects observed in cats and dogs following the use of flea and tick control pesticide products. Results of this survey are discussed and compared with pesticide incident reports collected by Health Canada. PMID:22467961

Turner, Vanessa; Chaffey, Cheryl; Ferrao, Patricia

2011-10-01

118

Cloning of the organophosphorus pesticide hydrolase gene clusters of seven degradative bacteria isolated from a methyl parathion contaminated site and evidence of their horizontal gene transfer  

Microsoft Academic Search

Seven organophosphorus pesticide-degrading bacteria harboring the methyl parathion degrading (mpd) gene were isolated from a methyl parathion contaminated site. In this study, the 4.7 kb mpd gene cluster, conserved in all seven bacteria capable of degrading methyl parathion, was cloned and further analysis revealed that this cluster contained five ORFs and the mpd gene was associated with a mobile element, IS6100.

Ruifu Zhang; Zhongli Cui; Xiaozhou Zhang; Jiandong Jiang; Ji-Dong Gu; Shunpeng Li

2006-01-01

119

Spatial variation in the degradation rate of the pesticides isoproturon, azoxystrobin and diflufenican in soil and its relationship with chemical and microbial properties  

Microsoft Academic Search

The extent of within field variability in the degradation rate of the pesticides isoproturon, azoxystrobin and diflufenican, and the role of intrinsic soil factors and technical errors in contributing to the variability, was investigated in sites on sandy-loam and clay-loam. At each site, 40 topsoil samples were taken from a 160×60m area, and pesticides applied in the laboratory. Time to

Gary D. Bending; Suzanne D. Lincoln; Rodney N. Edmondson

2006-01-01

120

What does the difference in the terbuthylazine degradation rate in selected soils of Apace Valley catchment means for the pesticide leaching potential?  

Microsoft Academic Search

The degradation of the selected pesticide terbuthylazine was investigated in the three different soil samples, which occurs frequently in agricultural area of Apace valley (53 km2), Slovenia. Selected soil samples were similar in organic matter content (1.9-2.1 %), pH (4.5-5.3), and in C\\/N ratio (7-9); whereas differed in texture (silty loam and loam) and in pesticide usage history (»integrated« and

Marjetka Suhadolc; Natasa Sibanc; Franc Lobnik

2010-01-01

121

Assessment of bioavailability of pesticides in soils and identification of pesticide degradation drivers using the in-situ Mass Distribution Quotient (iMDQ)  

NASA Astrophysics Data System (ADS)

The in-situ Mass Distribution Quotient (iMDQ) has recently been shown to reliably describe the bioavailability and mineralization of the widely applied pesticide isoproturon in agricultural soils. It is determined by pore water extraction from previously incubated soil samples and subsequent assessment of the mass distribution between solid and liquid phase. The method was verified by comparing the bioavailability with co-metabolic mineralization in soils under optimum microbial soil conditions (water tension -15 kPa and bulk density 1.3 g cm-3). A comparison of the results with the chemical partitioning assessed by the Kd method has shown a higher accuracy of the new method. By combining the iMDQ/pore water extraction method with mineralization of the pesticide under optimum microbial conditions in the soils, further information about mineralization and degradation processes could be obtained or confirmed: a) Metabolically outstanding soils could be identified due to inconsistency between bioavailability and mineralization when compared to the co-metabolic soils. In a metabolically hampered soil, the mineralization was very low compared to the bioavailability and in a soil with metabolically IPU degrading microorganisms the mineralization was extremely high despite low bioavailability. b) Analysis of metabolite patterns in soil water fractions of a degradation experiment allowed for an additional identification of the metabolic status of the soil. In co-metabolic soils, the diversity of metabolites increased proportionally with the degree of mineralization of the parent compound, whereas in a metabolically hampered soil the metabolite pattern was very diverse despite low mineralization. c) A quite stable fractioning between total mineralization of the parent compound to CO2 and build-up of non-extractable bound residues was found. This is a hint that also during co-metabolic degradation that can up to now not be attributed to a certain group of microorganisms, very similar processes take place in different soils. d) It could be shown that soil parameters governing the bioavailability of the compound differ between soils. Although TOC and pH could again be identified as the most important factors for the sorption strength of soils towards isoproturon, the bioavailability itself was driven by a combination of water content and sorption strength that was unique for each soil sample. f) The partitioning of parent compound and primary metabolites remained quite stable during the degradation and mineralization. Further investigations focusing on the microbial side of co-metabolic degradation are in progress. In the future, the method could be used to investigate more compounds, the effectiveness of methods to increase bioavailability in-situ without the need for degradation experiments, and the identification and analysis of degradation pathways in-situ. Other processes that are important for risk assessment, like leaching, have already been investigated with similar methods.

Folberth, Christian

2010-05-01

122

Low environmentally relevant levels of bioactive xenobiotics and associated degradation products cause cryptic perturbations of metabolism and molecular stress responses in Arabidopsis thaliana.  

PubMed

Anthropic changes and chemical pollution confront wild plant communities with xenobiotic combinations of bioactive molecules, degradation products, and adjuvants that constitute chemical challenges potentially affecting plant growth and fitness. Such complex challenges involving residual contamination and mixtures of pollutants are difficult to assess. The model plant Arabidopsis thaliana was confronted by combinations consisting of the herbicide glyphosate, the fungicide tebuconazole, the glyphosate degradation product aminomethylphosphonic acid (AMPA), and the atrazine degradation product hydroxyatrazine, which had been detected and quantified in soils of field margins in an agriculturally intensive region. Integrative analysis of physiological, metabolic, and gene expression responses was carried out in dose-response experiments and in comparative experiments of varying pesticide combinations. Field margin contamination levels had significant effects on plant growth and metabolism despite low levels of individual components and the presence of pesticide degradation products. Biochemical and molecular analysis demonstrated that these less toxic degradation products, AMPA and hydroxyatrazine, by themselves elicited significant plant responses, thus indicating underlying mechanisms of perception and transduction into metabolic and gene expression changes. These mechanisms may explain observed interactions, whether positive or negative, between the effects of pesticide products (AMPA and hydroxyatrazine) and the effects of bioactive xenobiotics (glyphosate and tebuconazole). Finally, the metabolic and molecular perturbations induced by low levels of xenobiotics and associated degradation products were shown to affect processes (carbon balance, hormone balance, antioxidant defence, and detoxification) that are likely to determine environmental stress sensitivity. PMID:23645866

Serra, Anne-Antonella; Nuttens, Andréďna; Larvor, Vanessa; Renault, David; Couée, Ivan; Sulmon, Cécile; Gouesbet, Gwenola

2013-07-01

123

Contamination by Persistent Chemical Pesticides in Livestock Production Systems  

Microsoft Academic Search

The impact of persistent organic pesticides represents one of the major environmental problems as reported in several studies\\u000a and reflected in some mandatory actions at the inter-governmental level. In particular, isomers of Hexachlorocyclohexane (HCH),\\u000a like many others Organochlorine Pesticides (OCPs), are of human health and environmental concern due to their persistence\\u000a in the biosphere. In industrialised countries, Lindane (the ?-isomer

Bruno Ronchi; Pier Paolo Danieli

124

Production of apple-based baby food: changes in pesticide residues.  

PubMed

Apples represent the main component of most fruit-based baby food products. Since not only fruit from organic farming, but also conventionally grown fruit is used for baby food production, the occurrence of pesticide residues in the final product is of high concern. To learn more about the fate of these hazardous compounds during processing of contaminated raw material, apples containing altogether 21 pesticide residues were used for preparation of a baby food purée both in the household and at industrial scale (in the baby food production facility). Within both studies, pesticide residues were determined in raw apples as well as in final products. Intermediate product and by-product were also analysed during the industrial process. Determination of residues was performed by a sensitive multi-detection analytical method based on liquid or gas chromatography coupled with mass spectrometry. The household procedure involved mainly the cooking of unpeeled apples, and the decrease of residues was not extensive enough for most of the studied pesticides; only residues of captan, dithianon and thiram dropped significantly (processing factors less than 0.04). On the other hand, changes in pesticide levels were substantial for all tested pesticides during apple processing in the industrial baby food production facility. The most important operation affecting the reduction of residues was removal of the by-products after pulping (rest of the peel, stem, pips etc.), while subsequent sterilisation has an insignificant effect. Also in this case, captan, dithianon and thiram were identified as pesticides with the most evident decrease of residues. PMID:24720736

Kovacova, Jana; Kocourek, Vladimir; Kohoutkova, Jana; Lansky, Miroslav; Hajslova, Jana

2014-01-01

125

PR notice 87-6. Notice to manufacturers, formulators, procedures, and registrants of pesticide products  

SciTech Connect

The document is one in the series of Pesticide Regulatory Notices, usually called PR Notices, which supplement the laws and regulations governing pesticide regulation in the US. These notices clarify, interpret and explain regulatory requirements and policies. They are directed at pesticide registrants and other parties interested in detailed procedures of regulation. This notice announces certain policies designed to reduce the potential for adverse effects from the use of pesticide products containing toxic inert ingredients. The agency is encouraging the use of the least toxic inert ingredient available and requiring the development of data necessary to determine the conditions of safe use of products containing toxic inert ingredients. In support of these policies, the Agency has categorized inert ingredients according to toxicity.

Not Available

1987-05-01

126

DEVELOPMENT OF A STRUCTURE-SEARCHABLE DATABASE FOR PESTICIDE METABOLITES AND ENVIRONMENTAL DEGRADATES  

EPA Science Inventory

USEPA is modifying and enhancing existing software for the depiction of metabolic maps to provide access via structures to metabolism information and associated data in EPA's Office of Pesticide Programs (OPP). The database includes information submitted to EPA in support of pest...

127

Degradation of pesticide waste taken from a highly contaminated soil evaporation pit in California  

Microsoft Academic Search

The primary methods for disposing of liquid pesticide wastes in California has been the dumping of the liquid materials into soil evaporation pits, ditches, and ponds. Many, if not most of these systems are unlined and have been in use for many years. One such soil pit located in northern California was found to be highly contaminated with an estimated

Wray Winterlin; James N. Seiber; Arthur Craigmill; Terry Baier; James Woodrow; Glen Walker

1989-01-01

128

DESIGNING PESTICIDE METABOLIC PATHWAY/DEGRADATE DATABASES FOR REGISTRANT SUBMITTED HEALTH EFFECTS/ECOLOGICAL EFFECTS DATA  

EPA Science Inventory

OPPTS requires information on the toxic effects of pesticide metabolites as well as the parent chemical. Currently, OPP receives metabolic maps with registrant study data submissions, but there is no efficient way to access previously submitted maps on similar chemicals to help w...

129

Impact of biofumigation with solarization on degradation of pesticides and heavy metal accumulation  

Microsoft Academic Search

A greenhouse study was conducted to evaluate the effect of biofumigation (with sheep and chicken manure) combined with solarization on the dissipation of pesticides (pyrifenox, DDT and dieldrin), and on soil metals accumulation. The treatments consisted of a control, and soil disinfestations by biofumigation combined with solarization (B+S) for two, four, five, six consecutive years. B+S enhanced the dissipation of

Pilar Flores; Alfredo Lacasa; Pedro Fernández; Pilar Hellín; José Fenoll

2008-01-01

130

EXPOSURE OF PRESCHOOL CHILDREN TO CHLORPYRIFOS AND ITS DEGRADATION PRODUCT 3,5,6-TRICHLORO-2-PYRIDINOL IN THEIR EVERYDAY ENVIRONMENTS  

EPA Science Inventory

As part of the Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) study, we investigated the exposures of preschool children to chlorpyrifos and its degradation product 3,5,6-trichloro-2-pyridinol (TCP) in their everyday environment...

131

Alginate biopolymer production by Azotobacter chroococcum from whey degradation  

Microsoft Academic Search

The potential of three Azotobacter chroococcum strains for whey degradation and alginate production were investigated. After dilution, samples were spread plated on isolation agar and Manitol agar and incubated at 30 °C for 24 h. Microorganisms were screened for their ability to whey degradation and alginate production based on colony morphology, negative and capsule staining, ability to decrease the apparent

A. Khanafari; A. Akhavan Sepahei

132

SAFE PESTICIDES/SAFE PRODUCTS MULTI-YEAR PLAN  

EPA Science Inventory

Additional research on pesticides and toxics provides results that support the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) and Toxic Substances Control Act (TSCA). EPA's multi-year research plan establishes four long-term goals, designed to enhance the Agency's Off...

133

Effect of Pesticides on the Diazotrophic Growth and Nitrogenase Activity of Purple Nonsulfur Bacteria  

Microsoft Academic Search

Application of pesticides for improving crop productivity has become necessary in the present day agricultural practices. This has resulted in either stimulatory or inhibitory effect on the soil microflora including nitrogen fixing organisms. Most of the pesticides, being xenobiotic, are degraded by very few microorganisms, which developed the tendency to degrade them while they may be toxic for others. Extensive

A. V. Chalam; C. Sasikala; C. V. Ramana; N. R. Uma; P. R. Rao

1997-01-01

134

Degradation of the pesticide carbofuran on clay and soil surfaces upon sunlight exposure.  

PubMed

In the present study, the photolysis of carbofuran has been undertaken under sunlight conditions and at the surface of model supports such as clay films and different soils collected from two different sites in Morocco (Tirs and Dahs). In all conditions, an efficient degradation occurred owing to direct light absorption and also to photoinduced processes involving either clays or natural organic matter moities. On kaolin films, the photodegradation kinetics appears to follow a first-order process that clearly depends on the film thickness. The diffusion of carbofuran from the lower part to the illuminated surface was found to be negligible when compared to the photolysis process within the range of 20-70 ?m. Thus, the photolysis rate constant at the surface of the solid support, k (0), was evaluated to be 7.0?×?10(-3) min(-1). Under these experimental conditions, the quantum yield was found equal to 2.1?×?10(-4). On soil surfaces, the disappearance rate constant was mainly attributed to photoinduced processes arising from natural organic matter. From the analytical point of view, the products were formed through (1) hydroxylation on the aromatic ring, (2) homolytic scission of the carbamate C-O bond leading to radical species formation, and (3) photohydrolysis of the carbamate C-O bond. PMID:24243162

Mountacer, H; Atifi, A; Wong-Wah-Chung, P; Sarakha, M

2014-03-01

135

Organophosphorous pesticide breakdown products in house dust and children's urine  

PubMed Central

Human exposure to preformed dialkylphosphates (DAPs) in food or the environment may affect the reliability of DAP urinary metabolites as biomarkers of organophosphate (OP) pesticide exposure. We conducted a study to investigate the presence of DAPs in indoor residential environments and their association with children’s urinary DAP levels. We collected dust samples from homes in farmworker and urban communities (40 homes total, n = 79 samples) and up to two urine samples from resident children ages 3–6 years. We measured six DAPs in all samples and eight DAP-devolving OP pesticides in a subset of dust samples (n = 54). DAPs were detected in dust with diethylphosphate (DEP) being the most frequently detected (?60%); detection frequencies for other DAPs were ?50%. DEP dust concentrations did not significantly differ between communities, nor were concentrations significantly correlated with concentrations of chlorpyrifos and diazinon, the most frequently detected diethyl-OP pesticides (Spearman ? = ?0.41 to 0.38, P>0.05). Detection of DEP, chlorpyrifos, or diazinon, was not associated with DEP and/or DEP + diethylthiophosphate detection in urine (Kappa coefficients = ?0.33 to 0.16). Finally, estimated non-dietary ingestion intake from DEP in dust was found to be ?5% of the dose calculated from DEP levels in urine, suggesting that ingestion of dust is not a significant source of DAPs in urine if they are excreted unchanged. PMID:22781438

Quiros-Alcala, Lesliam; Bradman, Asa; Smith, Kimberly; Weerasekera, Gayanga; Odetokun, Martins; Barr, Dana Boyd; Nishioka, Marcia; Castorina, Rosemary; Hubbard, Alan E.; Nicas, Mark; Hammond, S. Katharine; McKone, Thomas E.; Eskenazi, Brenda

2014-01-01

136

Toxicity and efficacy of selected pesticides and new acaricides to stored product mites (Acari: Acaridida).  

PubMed

Stored product mites can often infest stored products, but currently there is little information regarding the efficacy of pesticides that can be used for control. In this study we evaluated several common pesticides formulated from single active ingredients (a.i.) or commercially available mixtures (chlorpyrifos, deltamethrin, beta-cyfluthrin, and a combination of deltamethrin and S-bioallethrin), plus an acaricide composed of permethrin, pyriproxyfen and benzyl benzolate, for efficacy against Acarus siro, Tyrophagus putrescentiae, and Aleuroglyphus ovatus. The pesticides were incorporated into the mite diets in a dose range of 10-1000 microg a.i. g(-1) diet. Concentrations for suppression of 50 and 90% population growth and eradication (rC0) of mites were fit to linear regression models. None of the tested pesticides gave complete eradication of A. siro, which was the most tolerant of the three mite species tested. The most effective pesticide Allergoff 175 CS was a combination product (a nano-capsule suspension of permethrin, pyriproxyfen and benzyl benzolate) labeled for dust mites, with rC0 range of 463-2453 microg a.i. (permethrin) g(-1) diet depending on the species. Least effective were chlorpyrifos and deltamethrin. PMID:17674127

Hubert, Jan; Stejskal, Vaclav; Munzbergova, Zuzana; Hajslova, Jana; Arthur, Frank H

2007-01-01

137

Production and degradation of polyhydroxyalkanoates in waste environment  

Microsoft Academic Search

Polyhydroxyalkanoates (PHAs) are energy\\/carbon storage materials accumulated under unfavorable growth condition in the presence of excess carbon source. PHAs are attracting much attention as substitute for non-degradable petrochemically derived plastics because of their similar material properties to conventional plastics and complete biodegradability under natural environment upon disposal. In this paper, PHA production and degradation in waste environment as well as

Sang Yup Lee; Jong-il Choi

1999-01-01

138

Production and degradation of polyhydroxyalkanoates in waste environment  

E-print Network

waste has been investigated in order to utilize abundant organic compounds in waste water. Since PHAProduction and degradation of polyhydroxyalkanoates in waste environment Sang Yup Lee*, Jong- ment upon disposal. In this paper, PHA production and degradation in waste environment as well as its

139

Degradation of caffeic acid in subcritical water and online HPLC-DPPH assay of degradation products.  

PubMed

Caffeic acid was subjected to degradation under subcritical water conditions within 160-240 °C and at a constant pressure of 5 MPa in a continuous tubular reactor. Caffeic acid degraded quickly at these temperatures; the main products identified by liquid chromatography-diode array detection/mass spectrometry were hydroxytyrosol, protocatechuic aldehyde, and 4-vinylcatechol. The reaction rates for the degradation of caffeic acid and the formation of products were evaluated. Online high-performance liquid chromatography/2,2-diphenyl-1-picryhydrazyl assay was used to determine the antioxidant activity of each product in the solution. It was found that the overall antioxidant activity of the treated solution did not change during the degradation process. This study showed a potential of formation of antioxidants from natural phenolic compounds under these subcritical water conditions, and this may lead to a discovering of novel antioxidants compounds during the extraction by this technique. PMID:24483598

Khuwijitjaru, Pramote; Suaylam, Boonyanuch; Adachi, Shuji

2014-02-26

140

Time-dependent integrity during storage of natural surface water samples for the trace analysis of pharmaceutical products, feminizing hormones and pesticides  

PubMed Central

Monitoring and analysis of trace contaminants such as pharmaceuticals and pesticides require the preservation of the samples before they can be quantified using the appropriate analytical methods. Our objective is to determine the sample shelf life to insure proper quantification of ultratrace contaminants. To this end, we tested the stability of a variety of pharmaceutical products including caffeine, natural steroids, and selected pesticides under refrigerated storage conditions. The analysis was performed using multi-residue methods using an on-line solid-phase extraction combined with liquid chromatography tandem mass spectrometry (SPE-LC-MS/MS) in the selected reaction monitoring mode. After 21 days of storage, no significant difference in the recoveries was observed compared to day 0 for pharmaceutical products, while for pesticides, significant losses occurred for DIA and simazine after 10 days (14% and 17% reduction respectively) and a statistically significant decrease in the recovery was noted for cyanazine (78% disappearance). However, the estrogen and progestogen steroids were unstable during storage. The disappearance rates obtained after 21 days of storage vary from 63 to 72% for the feminizing hormones. Overall, pharmaceuticals and pesticides seem to be stable for refrigerated storage for up to about 10 days (except cyanazine) and steroidal hormones can be quite sensitive to degradation and should not be stored for more than a few days. PMID:20403158

2010-01-01

141

Eleven-year trend in acetanilide pesticide degradates in the Iowa River, Iowa.  

PubMed

Trends in concentration and loads of acetochlor, alachlor, and metolachlor and their ethanasulfonic (ESA) and oxanilic (OXA) acid degradates were studied from 1996 through 2006 in the main stem of the Iowa River, Iowa and in the South Fork Iowa River, a small tributary near the headwaters of the Iowa River. Concentration trends were determined using the parametric regression model SEAWAVE-Q, which accounts for seasonal and flow-related variability. Daily estimated concentrations generated from the model were used with daily streamflow to calculate daily and yearly loads. Acetochlor, alachlor, metolachlor, and their ESA and OXA degradates were generally present in >50% of the samples collected from both sites throughout the study. Their concentrations generally decreased from 1996 through 2006, although the rate of decrease was slower after 2001. Concentrations of the ESA and OXA degradates decreased from 3 to about 23% yr. The concentration trend was related to the decreasing use of these compounds during the study period. Decreasing concentrations and constant runoff resulted in an average reduction of 10 to >3000 kg per year of alachlor and metolachlor ESA and OXA degradates being transported out of the Iowa River watershed. Transport of acetochlor and metolachlor parent compounds and their degradates from the Iowa River watershed ranged from <1% to about 6% of the annual application. These trends were related to the decreasing use of these compounds during the study period, but the year-to-year variability cannot explain changes in loads based on herbicide use alone. The trends were also affected by the timing and amount of precipitation. As expected, increased amounts of water moving through the watershed moved a greater percentage of the applied herbicides, especially the relatively soluble degradates, from the soils into the rivers through surface runoff, shallow groundwater inflow, and subsurface drainage. PMID:23099949

Kalkhoff, Stephen J; Vecchia, Aldo V; Capel, Paul D; Meyer, Michael T

2012-01-01

142

Eleven-year trend in acetanilide pesticide degradates in the Iowa River, Iowa  

USGS Publications Warehouse

Trends in concentration and loads of acetochlor, alachlor, and metolachlor and their ethanasulfonic (ESA) and oxanilic (OXA) acid degradates were studied from 1996 through 2006 in the main stem of the Iowa River, Iowa and in the South Fork Iowa River, a small tributary near the headwaters of the Iowa River. Concentration trends were determined using the parametric regression model SEAWAVE-Q, which accounts for seasonal and flow-related variability. Daily estimated concentrations generated from the model were used with daily streamflow to calculate daily and yearly loads. Acetochlor, alachlor, metolachlor, and their ESA and OXA degradates were generally present in >50% of the samples collected from both sites throughout the study. Their concentrations generally decreased from 1996 through 2006, although the rate of decrease was slower after 2001. Concentrations of the ESA and OXA degradates decreased from 3 to about 23% yr-1. The concentration trend was related to the decreasing use of these compounds during the study period. Decreasing concentrations and constant runoff resulted in an average reduction of 10 to >3000 kg per year of alachlor and metolachlor ESA and OXA degradates being transported out of the Iowa River watershed. Transport of acetochlor and metolachlor parent compounds and their degradates from the Iowa River watershed ranged from <1% to about 6% of the annual application. These trends were related to the decreasing use of these compounds during the study period, but the year-to-year variability cannot explain changes in loads based on herbicide use alone. The trends were also affected by the timing and amount of precipitation. As expected, increased amounts of water moving through the watershed moved a greater percentage of the applied herbicides, especially the relatively soluble degradates, from the soils into the rivers through surface runoff, shallow groundwater inflow, and subsurface drainage.

Kalkhoff, Stephen J.; Vecchia, Aldo V.; Capel, Paul D.; Meyer, Michael T.

2012-01-01

143

The austral peregrine falcon: Color variation, productivity, and pesticides  

USGS Publications Warehouse

The austral peregrine falcon (Falco peregrinus cassini) was studied in the Andean foot- hills and across the Patagonian steppe from November to December 1981. The birds under study (18 pairs) were reproducing at or near normal (pre-DDT) levels for other races. Pesticide residues, while elevated, were well below the values associated with reproductive failure in other populations. With one exception, eggshells were not abnormally thin. The peregrine falcon in Patagonia exhibits extreme color variation. Pallid birds are nearly pure white below (light cream as juveniles), whereas normally pigmented birds are black-crowned and conspicuously barred with black ventrally. Rare individuals of the Normal Phase display black heads, broad black ventral barring, and warm reddish-brown ventral background coloration.

Ellis, D.H.

1985-01-01

144

Community air monitoring for pesticides. Part 1: selecting pesticides and a community.  

PubMed

The CA Department of Pesticide Regulation (CDPR) developed methods to select pesticides and a community to fulfill criteria for an ambient air monitoring study it conducted as part of the CA Environmental Protection Agency's Environmental Justice Action Plan. Using a scoring system, CDPR evaluated 100 pesticides based on statewide-reported pesticide use, volatility, and priority in CDPR's risk assessment process (indicators of exposure and toxicity) to produce a list of pesticides to consider as candidates for monitoring. The CDPR also evaluated and scored 83 communities based on demographics and health factors, availability of cumulative impacts data, and reported pesticide use to create a list of community candidates. The scores provide relative rankings to distinguish more highly impacted communities from less impacted ones and to identify which pesticides might contribute most to potential adverse health effects. These methods use criteria that can be quantified, validated, and verified in order to provide a transparent and fair selection process. Based on public comments and highest scores, CDPR recommended 40 pesticides (including some of their degradation products) and one community for its yearlong monitoring study. The CDPR then further refined its list of pesticides by soliciting input from local and technical advisory groups. The CDPR plans to use these methods to select pesticides and communities in future monitoring activities. PMID:24362496

Segawa, Randy; Levine, Johanna; Neal, Rosemary; Brattesani, Madeline

2014-03-01

145

Facile Synthesis of Hierarchical Porous TiO2 Ceramics with Enhanced Photocatalytic Performance for Micropolluted Pesticide Degradation.  

PubMed

In this research, hierarchical porous TiO2 ceramics were successfully synthesized through a camphene-based freeze-drying route. The well-dispersed TiO2 slurries were first frozen and dried at room temperature, followed by high-temperature sintering. The ceramics were analyzed by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy. Results indicated that the obtained TiO2 ceramics could inhibit undesirable anatase-to-rutile phase transformation and grain growth even at temperatures as high as 800 °C. In this experiment, optimal compressive strength and porosity of the TiO2 ceramics were produced with the initial TiO2 slurry content of ?15 wt %. The resultant TiO2 ceramics performed excellently in the photodegradation of atrazine and thiobencarb, and the total organic carbon removal efficiency was up to 95.7% and 96.7%, respectively. More importantly, the TiO2 ceramics were easily recyclable. No obvious changes of the photocatalytic performance were observed after six cycles. Furthermore, the ceramics also effectively degraded other pesticides such as dimethoate, lindane, dipterex, malathion, and bentazone. These hierarchical porous TiO2 ceramics have potential applications in environmental cleanup. PMID:25198508

Xing, Zipeng; Zhou, Wei; Du, Fan; Zhang, Linlin; Li, Zhenzi; Zhang, Hang; Li, Wei

2014-10-01

146

Screening of nerve agent degradation products by MALDI-TOFMS.  

PubMed

A novel method for the rapid screening of degradation products derived from nerve agents by matrix-assisted laser desorption ionization time-of-flight mass spectrometry is described. Five standard products were selected as model compounds, including isopropyl methylphosphonic acid (IMPA), pinacolyl methylphosphonic acid (PMPA), ethyl methylphosphonic acid (EMPA), isobutyl methylphosphonic acid (i-BuMPA), and cyclohexyl methylphosphonic acid (CHMPA), which are degradation products of Sarin (GB), Soman (GD), VX, Russian VX (RVX), and GF, respectively. For comparison, CHCA (alpha-cyano-4-hydroxycinnamic acid) and DCCA (7-(diethylamino)coumarin-3-carboxylic acid) were used as the MALDI-matrix when the third harmonic generation (355 nm) of a Nd:YAG laser and a hydrogen Raman laser (multifrequency laser) were used, respectively. The method permitted the five nerve agent degradation products to be screened rapidly and successfully, suggesting that it has the potential for use as a routine monitoring tool. PMID:16808484

Shu, You-Ren; Su, An-Kai; Liu, Ju-Tsung; Lin, Cheng-Huang

2006-07-01

147

A study of the products of PVC thermal degradation  

Microsoft Academic Search

PVC thermal degradation in vacuum up to 500 °C has been followed by recording the relative rate of volatile product formation by thermal volatilisation analysis while monitoring by mass spectrometry the formation of the main products: HCl, aromatic and aliphatic hydrocarbons, and non-condensable gases (CH4, H2). The material balance after pyrolysis has been evaluated. The liquid fraction collected during pyrolysis

Ian C. McNeill; Livia Memetea; William J. Cole

1995-01-01

148

Comparison of linuron degradation in the presence of pesticide mixtures in soil under laboratory conditions.  

PubMed

It is widely recognised that complex interactions occur between chemicals in mixtures. In many agricultural situations, the use of tank mixes and complex spray programs is a common practice. Insecticides, fungicides and a herbicide being applied in potato protection were used in this research. Interactions between linuron and insecticides, such as thiamethoxam or clothianidin, and fungicides, such as mancozeb or chlorothalonil, were examined in soil. The degradation rate of linuron in soil during laboratory incubation in six treatments was studied. Mixtures of linuron with mancozeb in sandy loam and clay loam soils had a significant effect on the persistence of this herbicide. For example, for the same herbicide, t 1/2 values for linuron were from 37 days in sandy loam to 44 days in clay loam. These values changed (64-67 days) when thiamethoxam and mancozeb were in soil. When mancozeb was added only, the half-life values were from 59 to 62 days, respectively. Other mixtures with chlorothalonil, thiamethoxam and clothianidin did not have any effect. In order to compare linuron degradation rates in soils, a single first-order model and expanded statistical analysis were used. PMID:23525775

Swarcewicz, Maria; Gregorczyk, Andrzej; Sobczak, Justyna

2013-10-01

149

A multi-residue method for the analysis of pesticides and pesticide degradates in water using HLB solid-phase extraction and gas chromatography-ion trap mass spectrometry  

USGS Publications Warehouse

A method was developed for the analysis of over 60 pesticides and degradates in water by HLB solid-phase extraction and gas-chromatography/mass spectrometry. Method recoveries and detection limits were determined using two surface waters with different dissolved organic carbon (DOC) concentrations. In the lower DOC water, recoveries and detection limits were 80%-108% and 1-12 ng/L, respectively. In the higher DOC water, the detection limits were slightly higher (1-15 ng/L). Additionally, surface water samples from four sites were analyzed and 14 pesticides were detected with concentrations ranging from 4 to 1,200 ng/L. ?? 2008 Springer Science+Business Media, LLC.

Hladik, M.L.; Smalling, K.L.; Kuivila, K.M.

2008-01-01

150

Dioxin/POPs legacy of pesticide production in Hamburg: part 1--securing of the production area.  

PubMed

?-Hexachlorocyclohexane (HCH), ?-HCH, and ?-HCH (lindane) were recently included as new persistent organic pollutants (POPs) in the Stockholm Convention. Therefore, the chemicals need to be globally addressed, including the disposal of historic wastes. At most sites, the approximately 85% of HCH waste isomers were dumped. At a former lindane factory in Hamburg and some other factories the HCH, waste was recycled producing residues with high polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/PCDF) levels. The soil and ground water under the former pesticide factory was/is highly contaminated with HCH (260 tons), chlorobenzenes (550 tons), and PCDD/PCDF (6 kg toxic equivalents (TEQ)). This contamination did not result from disposal operations but from spillages and leakages during the 30 years of the factory's production history. A containment wall has been constructed around the production area to prevent the dispersal of the pollutants. The ground water is managed by a pump and treat system. Over the last 15 years, approximately 10-30 tons of this pollution reservoir has been pumped and incinerated. For the contaminated production buildings, specific assessment and demolition technologies have been applied. In addition to their HCH waste isomer deposition, former lindane/HCH productions need to be assessed for possible recycling practice of HCH and related PCDD/PCDF contamination of the production area and buildings. Since such recycling activities have taken place at several factories in different countries, the experience of assessment and management of the described production area and contaminated buildings could be valuable. Such assessment could be addressed within the frame of the Stockholm Convention. PMID:22777609

Weber, Roland; Varbelow, Hans Gerhard

2013-04-01

151

Zero-valent iron mediated degradation of ciprofloxacin - Assessment of adsorption, operational parameters and degradation products.  

PubMed

The zero-valent iron (ZVI) mediated degradation of the antibiotic ciprofloxacin (CIP) was studied under oxic condition. Operational parameters such as ZVI concentration and initial pH value were evaluated. Increase of the ZVI concentration from 1 to 5gL(-1) resulted in a sharp increase of the observed pseudo-first order rate constant of CIP degradation, reaching a plateau at around 10gL(-1). The contribution of adsorption to the overall removal of CIP and dissolved organic carbon (DOC) was evaluated after a procedure of acidification to pH 2.5 with sulfuric acid and sonication for 2min. Adsorption increased as pH increased, while degradation decreased, showing that adsorption is not important for degradation. Contribution of adsorption was much more important for DOC removal than for CIP. Degradation of CIP resulted in partial defluorination since the fluoride measured corresponded to 34% of the theoretical value after 120min of reaction. Analysis by liquid chromatography coupled to mass spectrometry showed the presence of products of hydroxylation on both piperazine and quinolonic rings generating fluorinated and defluorinated compounds as well as a product of the piperazine ring cleavage. PMID:25150686

Perini, Joăo Angelo de Lima; Silva, Bianca Ferreira; Nogueira, Raquel F Pupo

2014-12-01

152

Photochemical fluorimetric analysis of phenylbutazone and its degradation products.  

PubMed

A room temperature photochemical spectrofluorimetric (RTPF) method has been developed for the assay of phenylbutazone (PB), and its major degradation products. Fluorescence spectral properties of PB, its degradation products, and their photoproducts are reported, as well as the optimal irradiation times (ranging from 4 to 45 min), which correspond to maximum fluorescence signals of photoproducts. Linear log-log calibration plots were obtained over a 50- to 1000-fold range of concentration, and limits of detection ranged between 1 ng/ml and 1.2 micrograms/ml. This has been shown to be a convenient technique, in terms of simplicity, short measurement times, sensitivity, and precision. PMID:2490547

Fricoteaux, R; Aaron, J J; Quaglia, M G

1989-01-01

153

75 FR 52737 - Pesticide Product Registrations; Unconditional and Conditional Approvals  

Federal Register 2010, 2011, 2012, 2013

...ingredient: EPA received an application from Plasma Power Limited of India, c/o OMC Ag...for the registration of two products: Plasma Neem Oil Manufacturing Use Product EPA...one end-use product was registered: Plasma Neem Oil Biological insecticide,...

2010-08-27

154

Hydrogeology and Water Quality of the Pepacton Reservoir Watershed in Southeastern New York. Part 1. Concentrations of pesticides and their degradates in stream baseflow, 2000-2001  

USGS Publications Warehouse

Baseflow samples were collected from 20 small streams in the Pepacton Reservoir watershed in Delaware County, N.Y., from December 2000 through November 2001 as part of an investigation to define the occurrence of pesticides in shallow ground water in watersheds containing either a recent (2001) corn crop, a previous (1993-94) corn crop, or no history of row-crop cultivation. Baseflow water quality was assumed to represent the chemical quality of shallow ground water within the drainage area above each sampling site. Baseflow samples were analyzed for 57 pesticides and pesticide degradates. Three herbicides (atrazine, metolachlor and simazine) and three herbicide degradates (alachlor ESA [ethanesulfonic acid], deethylatrazine, and metolachlor ESA) were detected, but no concentrations exceeded any Federal or State water-quality criteria, and the maximum concentrations of all compounds except metolachlor ESA were less than 0.10 microgram per liter. The most frequently detected compounds (atrazine, metolachlor, deethylatrazine and metolachlor ESA) are either those typically used on corn crops, or those whose parent compounds are commonly used on corn crops and have been detected in streams that drain row-crop settings elsewhere in New York State. The pesticide and pesticide-degradate concentrations in baseflow samples collected in December 2000 and July 2001 samples generally corresponded to the amount of cornfield acreage in each watershed in 2001. The types of pesticides detected, and their median concentrations, were similar to those noted in two previous ground-water studies in row-crop areas elsewhere in upstate New York. Also the SAM ratios (ratio of metolachlor ESA concentration to metolachlor concentration) for the Pepacton samples were similar to those for ground-water samples from other agricultural settings in upstate New York, but were significantly higher than that for stormflow and baseflow samples collected in 1997-98 from Canajoharie Creek, an upstate stream that drains row-crop farmland. These comparisons confirm that the baseflow samples were derived from, and were representative of, ground water in their respective watersheds. Late-summer decreases in atrazine and deethylatrazine concentrations at a site where corn was grown in 2001 may have resulted from the seasonally dry conditions and the accompanying decrease in ground-water discharge from the upper-most part of the surficial aquifer system to streams. The lack of a similar decrease in metolachlor ESA concentrations during this period may reflect the transport of metolachlor ESA to deeper parts of the surficial aquifer that continued to discharge to streams during the dry period.

Phillips, Patrick J.; Heisig, Paul M.

2004-01-01

155

Exposures of preschool children to chlorpyrifos and its degradation product 3,5,6-trichloro-2-pyridinol in their everyday environments  

Microsoft Academic Search

As part of the Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) study, we investigated the exposures of preschool children to chlorpyrifos and its degradation product 3,5,6-trichloro-2-pyridinol (TCP) in their everyday environments. During this study, the participants were still able to purchase and apply chlorpyrifos at their homes or day care centers. Participants were recruited randomly

Marsha K Morgan; Linda S Sheldon; Carry W Croghan; Paul A Jones; Gary L Robertson; Jane C Chuang; Nancy K Wilson; Christopher W Lyu

2005-01-01

156

A general model for estimating the economic and production effects of specified pesticide withdrawals: a cotton application  

E-print Network

A GENERAL MODEL FOR ESTIMATING THE ECONOMIC AND PRODUCTION EFFECTS OF SPECIFIED PESTICIDE WITHDRAWALS: A COTTON APPLICATION A Thesis by JAMES E(~CASEY, JR. Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE December 1973 Major Subject: Agricultural Economics A GENERAL MODEL FOR ESTIMATING THE ECONOMIC AND PRODUCTION EFFECTS OF SPECIFIED PESTICIDE WITHDRAWALS: A COTTON APPLICATION A Thesis by JAMES E. CASEY...

Casey, James Elmer

2012-06-07

157

Development of a sensor for polypropylene degradation products.  

SciTech Connect

This paper presents the development of a sensor to detect the oxidative and radiation induced degradation of polypropylene. Recently we have examined the use of crosslinked assemblies of nanoparticles as a chemiresistor-type sensor for the degradation products. We have developed a simple method that uses a siloxane matrix to fabricate a chemiresistor-type sensor that minimizes the swelling transduction mechanism while optimizing the change in dielectric response. These sensors were exposed with the use of a gas chromatography system to three previously identified polypropylene degradation products including 4-methyl-2-pentanone, acetone, and 2-pentanone. The limits of detection 210 ppb for 4-methy-2-pentanone, 575 ppb for 2-pentanone, and the LoD was unable to be determined for acetone due to incomplete separation from the carbon disulfide carrier.

Sawyer, Patricia Sue; Howell, Stephen Wayne; Hochrein, James Michael; Dirk, Shawn M.; Bernstein, Robert; Washburn, Cody M.; Graf, Darin C.

2009-04-01

158

A fish of many scales: extrapolating sublethal pesticide exposures to the productivity of wild salmon populations.  

PubMed

For more than a decade, numerous pesticides have been detected in river systems of the western United States that support anadromous species of Pacific salmon and steelhead. Over the same interval, several declining wild salmon populations have been listed as either threatened or endangered under the U.S. Endangered Species Act (ESA). Because pesticides occur in surface waters that provide critical habitat for ESA-listed stocks, they are an ongoing concern for salmon conservation and recovery throughout California and the Pacific Northwest. Because pesticide exposures are typically sublethal, a key question is whether toxicological effects at (or below) the scale of the individual animal ultimately reduce the productivity and recovery potential of wild populations. In this study we evaluate how the sublethal impacts of pesticides on physiology and behavior can reduce the somatic growth of juvenile chinook salmon (Oncorhynchus tshawytscha) and, by extension, subsequent size-dependent survival when animals migrate to the ocean and overwinter in their first year. Our analyses focused on the organophosphate and carbamate classes of insecticides. These neurotoxic chemicals have been widely detected in aquatic environments. They inhibit acetylcholinesterase, an enzyme in the salmon nervous system that regulates neurotransmitter-mediated signaling at synapses. Based on empirical data, we developed a model that explicitly links sublethal reductions in acetylcholinesterase activity to reductions in feeding behavior, food ration, growth, and size at migration. Individual size was then used to estimate size-dependent survival during migration and transition to the sea. Individual survival estimates were then integrated into a life-history population projection matrix and used to calculate population productivity and growth rate. Our results indicate that short-term (i.e., four-day) exposures that are representative of seasonal pesticide use may be sufficient to reduce the growth and size at ocean entry of juvenile chinook. The consequent reduction in individual survival over successive years reduces the intrinsic productivity (lambda) of a modeled ocean-type chinook population. Overall, we show that exposures to common pesticides may place important constraints on the recovery of ESA-listed salmon species, and that simple models can be used to extrapolate toxicological impacts across several scales of biological complexity. PMID:20014574

Baldwin, David H; Spromberg, Julann A; Collier, Tracy K; Scholz, Nathaniel L

2009-12-01

159

Solar photocatalytic activity of TiO2 modified with WO3 on the degradation of an organophosphorus pesticide.  

PubMed

In this study, the solar photocatalytic activity (SPA) of WO3/TiO2 photocatalysts synthesized by the sol-gel method with two different percentages of WO3 (2 and 5%wt) was evaluated using malathion as a model contaminant. For comparative purpose bare TiO2 was also prepared by sol-gel process. The powders were characterized by X-ray diffraction (XRD), Raman spectroscopy, diffuse reflectance UV-vis spectroscopy (DRUV-vis), specific surface area by the BET method (SSABET), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy with a high annular angle dark field detector (STEM-HAADF). The XRD, Raman, HRTEM and STEM-HAADF analyses indicated that WO3 was present as a monoclinic crystalline phase with nanometric cluster sizes (1.1 ± 0.1 nm for 2% WO3/TiO2 and 1.35 ± 0.3 nm for 5% WO3/TiO2) and uniformly dispersed on the surface of TiO2. The particle size of the materials was 19.4 ± 3.3 nm and 25.6 ± 3 nm for 2% and 5% WO3/TiO2, respectively. The SPA was evaluated on the degradation of commercial malathion pesticide using natural solar light. The 2% WO3/TiO2 photocatalyst exhibited the best photocatalytic activity achieving 76% of total organic carbon (TOC) abatement after 300 min compared to the 5% WO3/TiO2 and bare TiO2 photocatalysts, which achieved 28 and 47% mineralization, respectively. Finally, experiments were performed to assess 2% WO3/TiO2 catalyst activity on repeated uses; after several successive cycles its photocatalytic activity was retained showing long-term stability. PMID:23993423

Ramos-Delgado, N A; Gracia-Pinilla, M A; Maya-Trevińo, L; Hinojosa-Reyes, L; Guzman-Mar, J L; Hernández-Ramírez, A

2013-12-15

160

Impact of pesticide restrictions on regional production patterns  

Microsoft Academic Search

A national and interregional programming model is analyzing the effects of banning Chlordane and Heptachlor from U.S. agriculture. The model has sectors for land and water resources, crop and livestock production, commodity transportation and domestic and foreign demand. The central Corn Belt would be put at some disadvantage and lose production to other regions. Soybeans and small grains would replace

Gary Vocke; Earl O. Heady

1978-01-01

161

Glucose Degradation Products in Peritoneal Dialysis: From Bench to Bedside  

Microsoft Academic Search

In continuous ambulatory peritoneal dialysis patients, treatment success is inextricably linked to the functional and morphological integrity of the peritoneal membrane. This membrane, however, is repeatedly exposed to peritoneal dialysis fluids (PDFs) with unphysiological composition (e.g., acidic pH, high glucose content, hyperosmolarity). More recently, attention of researchers and clinicians has been focused on the presence of glucose degradation products (GDPs)

Achim Jörres

2003-01-01

162

Baby food production chain: Pesticide residues in fresh apples and products  

Microsoft Academic Search

During 3 years of a monitoring programme, 522 samples of fresh apples, six brands of fruit purées and various types of fruit baby food prepared from these materials were analysed. Each sample was examined for the presence of 86 GC amenable pesticide residues. The reporting limits of the procedure employed for sample analyses were in the range 0.003–0.01?mg?kg. Pesticide residues

R. Št?pán; J. Tichá; J. Hajšlová; T. Kovalczuk; V. Kocourek

2005-01-01

163

Pesticides in Ground Water of Central and Western Maryland  

USGS Publications Warehouse

Selected pesticides and degradates (products of pesticide degradation) are detectable in ground water in many parts of central and western Maryland, although concentrations are generally less than 0.1 micrograms per liter. Ground-water samples collected recently (1994-2003) from 72 wells in areas of Maryland underlain by consolidated carbonate, crystalline, or siliciclastic aquifers (areas north and west of the Fall Line) were analyzed for selected pesticides and degradates. Pesticides were typically detected in mixtures of multiple compounds in ground water, and degradates were commonly detected, often at greater concentrations than their respective parent compounds. No pesticides were observed at concentrations greater than established standards for drinking water, and nearly all observed concentrations were below other health-based guidelines. Although such standards and guidelines are generally much greater than measured concentrations in ground water, they do not exist for many detected compounds (particularly degradates), or for mixtures of multiple compounds. The distribution of pesticides and degradates in ground water is related to application practices, as well as chemical and environmental factors that affect the fate and movement of individual compounds.

Ator, Scott W.; Reyes, Betzaida

2008-01-01

164

75 FR 82387 - Product Cancellation Order for Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...dated August 25, 2010, pertains to the fenoxycarb product registrations and the notice...receive any comments on the notice for fenoxycarb or propetamphos and neither request...EPA has established a docket for the fenoxycarb action under docket...

2010-12-30

165

75 FR 62387 - Pesticide Product Registrations; Conditional Approval  

Federal Register 2010, 2011, 2012, 2013

...end-use products (EPA File Symbol 55050-G), containing...fumigant use (EPA File Symbol 55050-U), containing...fumigant use (EPA File Symbol 55050-L), containing...forest nursery crops. List of Subjects Environmental protection, Chemicals, Pests and...

2010-10-08

166

75 FR 30829 - Antimicrobial Pesticide Products; Registration Applications  

Federal Register 2010, 2011, 2012, 2013

...ingredient: Nanosilver. Proposed Use(s): Antimicrobial and preservative additive used to treat fibers, plastics, polymers, latex products and ceramics. Contact: Demson Fuller, (703) 308-8062; fuller.demson@epa.gov. List of...

2010-06-02

167

77 FR 10515 - Pesticide Product Registrations; Conditional Approval  

Federal Register 2010, 2011, 2012, 2013

...preservative additive used to treat fibers, plastics, polymers, latex products and ceramics (EPA File Symbol 85249-R...limiting use to the treatment of fibers only. This active ingredient...preservative additive used to treat fibers. List of Subjects...

2012-02-22

168

The quantity and quality of dissolved organic matter as supplementary carbon source impacts the pesticide-degrading activity of a triple-species bacterial biofilm.  

PubMed

Effects of environmental dissolved organic matter (eDOM) that consists of various low concentration carbonic compounds on pollutant biodegradation by bacteria are poorly understood, especially when it concerns synergistic xenobiotic-degrading consortia where degradation depends on interspecies metabolic interactions. This study examines the impact of the quality and quantity of eDOM, supplied as secondary C-source, on the structure, composition and pesticide-degrading activity of a triple-species bacterial consortium in which the members synergistically degrade the phenylurea herbicide linuron, when grown as biofilms. Biofilms developing on 10 mg L?ą linuron showed a steady-state linuron degradation efficiency of approximately 85 %. The three bacterial strains co-localized in the biofilms indicating syntrophic interactions. Subsequent feeding with eDOM or citrate in addition to linuron resulted into changes in linuron-degrading activity. A decrease in linuron-degrading activity was especially recorded in case of co-feeding with citrate and eDOM of high quality and was always associated with accumulation of the primary metabolite 3,4-dichloroaniline. Improvement of linuron degradation was especially observed with more recalcitrant eDOM. Addition of eDOM/citrate formulations altered biofilm architecture and species composition but without loss of any of the strains and of co-localization. Compositional shifts correlated with linuron degradation efficiencies. When the feed was restored to only linuron, the linuron-degrading activity rapidly changed to the level before the mixed-substrate feed. Meanwhile only minor changes in biofilm composition and structure were recorded, indicating that observed eDOM/citrate effects had been primarily due to repression/stimulation of linuron catabolic activity rather than to biofilm characteristics. PMID:23653124

Horemans, Benjamin; Vandermaesen, Johanna; Breugelmans, Philip; Hofkens, Johan; Smolders, Erik; Springael, Dirk

2014-01-01

169

76 FR 34979 - Product Cancellation Order for Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...products listed in Table 1 of Unit II., pursuant to section 6(f...registrants listed in Table 2 of Unit II. to voluntarily cancel these...number is (703) 305-5805. II. What action is the agency taking...Rootone F Brand Rooting...

2011-06-15

170

76 FR 16417 - Product Cancellation Order for Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...Registration No. Product name Active ingredients...000239-02664.................. Weed B Gon Ready- Benzoic acid, 3,6...AEH Super Glufosinate Concentrate Weed, Grass and Brush Killer. 000432-00552...Scott's Lawn Pro MCPA (and salts and Weed N' 'Feed. esters) Mecoprop...

2011-03-23

171

Modern pesticides and bobwhite populations  

USGS Publications Warehouse

Bobwhite (Colinus virginianus) are frequently used as test animals for wildlife tests of pesticides. The organophosphate and carbamate pesticides that have replaced the organochlorines have many desirable properties, but they span a wide range of acute toxicities and some of them affe,ct survival, reproduction, food consumption, behavior, and nervous system enzymes in laboratory tests. Applying these laboratory findings to the field requires assumptions about the severity of exposure in the field. Direct field measurements show that birds may be exposed to significant amounts of these pesticides or even more toxic degradation products under some conditions. Adverse population effects may also result from depression of insect populations during the seasons when bobwhites rely on insects for food.

Stromborg, K.L.

1982-01-01

172

Pesticide occurrence in groundwater in areas of high-density row crop production in Alabama, 2009  

USGS Publications Warehouse

High-density row crop production occurs in three areas of Alabama that are underlain by productive aquifers, northern Alabama, southeastern Alabama, and Baldwin County in southwestern Alabama. The U.S. Geological Survey collected five groundwater samples from each of these three areas during 2009 for analysis of selected pesticides. Results of these analyses showed detections for 37 of 152 analytes. The three most frequently detected compounds were atrazine, 2-Chloro-4-isopropylamino-6-amino-triazine (CIAT), and metolachlor. The highest concentration for any analyte was 4.08 micrograms per liter for metolachlor.

Moreland, Richard S.

2011-01-01

173

'Pesticide Use in Banana and Plantain Production and Risk Perception Among Local Actors in Talamanca, Costa Rica'  

Microsoft Academic Search

The Talamanca County in Costa Rica has large-scale banana and small-scale plantain production, probably causing pesticide exposure in indigenous children. We explored to what extent different community actors are aware of children's pesticide hazards and how their awareness related to socio-economical and cultural conditions. Methods comprised eight focus groups with fathers and mothers separately, 27 semi-structured interviews to key actors,

D. A. Barraza-Ruiz; K. Jansen; Wendel de Joode van B; C. Wesseling

2011-01-01

174

Pesticide use in banana and plantain production and risk perception among local actors in Talamanca, Costa Rica  

Microsoft Academic Search

The Talamanca County in Costa Rica has large-scale banana and small-scale plantain production, probably causing pesticide exposure in indigenous children. We explored to what extent different community actors are aware of children's pesticide hazards and how their awareness related to socio-economical and cultural conditions. Methods comprised eight focus groups with fathers and mothers separately, 27 semi-structured interviews to key actors,

Douglas Barraza; Kees Jansen; Berna van Wendel de Joode; Catharina Wesseling

2011-01-01

175

Life- cycle assessment in pesticide product development: methods and case study on two plant-growth regulators from different product generations.  

PubMed

Environmental assessments in pesticide product development are generally restricted to plant uptake and emissions of active ingredients. Life-cycle assessment (LCA) enables a more comprehensive evaluation by additionally assessing the impacts of pesticide production and application (e.g. tractor operations). The use of LCA in the product development of pesticides, in addition to the methods commonly applied, is therefore advisable. In this paper a procedure for conducting LCA in early phases of product development is proposed. In a case study, two plant-growth regulators from different product generations were compared regarding their application in intensive production of winter wheat. The results showed thatthe reduced emissions from active ingredients of the newer pesticide were compensated by higher impacts from the production process. The authors draw the conclusion that it is important to consider environmental objectives in the procurement of precursors, in addition to the classical goals of increasing the efficacy and reducing the nontarget effects of pesticides. Moreover, the case study showed that decisions based on uncertain results in early stages of product development may need to be revised in later stages, e.g. based on investigations of pesticides' effects on crop yield. PMID:15871283

Geisler, Georg; Hellweg, Stefanie; Hofstetter, Thomas B; Hungerbuehler, Konrad

2005-04-01

176

Pesticide use in banana and plantain production and risk perception among local actors in Talamanca, Costa Rica  

SciTech Connect

The Talamanca County in Costa Rica has large-scale banana and small-scale plantain production, probably causing pesticide exposure in indigenous children. We explored to what extent different community actors are aware of children's pesticide hazards and how their awareness related to socio-economical and cultural conditions. Methods comprised eight focus groups with fathers and mothers separately, 27 semi-structured interviews to key actors, and field observations. As a whole, the indigenous plantain farmers and banana plantation workers had some general knowledge of pesticides concerning crop protection, but little on acute health effects, and hardly any on exposure routes and pathways, and chronic effects. People expressed vague ideas about pesticide risks. Inter-community differences were related to pesticide technologies used in banana and plantain production, employment status on a multinational plantation versus smallholder status, and gender. Compared to formalized practices on transnational company plantations, where workers reported to feel protected, pesticide handling by plantain smallholders was not perceived as hazardous and therefore no safety precautions were applied. Large-scale monoculture was perceived as one of the most important problems leading to pesticide risks in Talamanca on banana plantations, and also on neighboring small plantain farms extending into large areas. Plantain farmers have adopted use of highly toxic pesticides following banana production, but in conditions of extreme poverty. Aerial spraying in banana plantations was considered by most social actors a major determinant of exposure for the population living nearby these plantations, including vulnerable children. We observed violations of legally established aerial spraying distances. Economic considerations were most mentioned as the underlying reason for the pesticide use: economic needs to obtain the production quantity and quality, and pressure to use pesticides by other economic agents such as middlemen. Risk perceptions were modulated by factors such as people's tasks and positions in the production process, gender, and people's possibilities to define their own social conditions (more fatalistic perceptions among banana workers). The challenge for the future is to combine these insights into improved health risk assessment and management that is culturally adequate for each particular community and agricultural context. - Research highlights: {yields} A first study on pesticide risk perception in Costa Rica. {yields} One of the few studies performed in the indigenous populations in Talamanca. {yields} Economic considerations prevailed above health risks in both communities. {yields} Our findings provide valuable information for multiple social actors.

Barraza, Douglas, E-mail: dbarraza@una.ac.cr [Central American Institute for Studies on Toxic Substances, Universidad Nacional, Heredia (Costa Rica) [Central American Institute for Studies on Toxic Substances, Universidad Nacional, Heredia (Costa Rica); Technology and Agrarian Development Group, Wageningen University (Netherlands); Jansen, Kees [Technology and Agrarian Development Group, Wageningen University (Netherlands)] [Technology and Agrarian Development Group, Wageningen University (Netherlands); Wendel de Joode, Berna van; Wesseling, Catharina [Central American Institute for Studies on Toxic Substances, Universidad Nacional, Heredia (Costa Rica)] [Central American Institute for Studies on Toxic Substances, Universidad Nacional, Heredia (Costa Rica)

2011-07-15

177

Analysis of polyolefin stabilizers and their degradation products.  

PubMed

Polymeric materials are complex samples, as they contain various groups of additives, compounding ingredients, and fillers. An important group of additives are stabilizers. Efficient stabilization is essential especially for polypropylene, as it is sensitive to oxidation and radical attack due to the numerous tertiary carbon atoms in its structure. How long a polymer will be sufficiently stabilized can be deduced from the contained amount of intact stabilizer. Different approaches for the analysis of stabilizers in polyolefins are available, which include sample preparation with subsequent chromatographic separation as well as direct analysis techniques. In round-robin tests, stabilizer concentrations obtained varied strongly. This shows the demand for reliable and robust methods. Stabilizers get consumed while protecting the polymer and are then present as degradation products. They were observed while quantifying intact stabilizers, in migration studies, and - if volatile - in emission studies of polymers. Furthermore, e.g. interactions with other polymer ingredients or irradiation degraded stabilizers. The identification of degradation products provides a better insight into the reactions associated with stabilization. Their quantitation makes it possible to deduce the original level of stabilization. Furthermore, polymer ingredients degrading stabilizers can be identified. Knowledge on these interactions contributes significantly to improved polymer stabilization. PMID:21086426

Reingruber, Eva; Buchberger, Wolfgang

2010-11-01

178

Exploring the functional diversity of the supraglacial environment: Microbial degradation of the pesticide 2,4-D on the Greenland Ice Sheet  

NASA Astrophysics Data System (ADS)

The surface of the Greenland ice sheet (GrIS) harbours a diverse community of heterotrophic microorganisms. Organic compounds of anthropogenic origin, including pesticides, are deposited on the GrIS; however, the fate of these compounds in the ice is currently unknown. In this study we determine the potential of the microbial community from the surface of the GrIS to mineralise the pesticide 2,4-dichlorophenoxyacetic acid (2,4-D). It is one of the most easily degraded compounds among the phenoxyacetic acid pesticides, and the ability to mineralise 2,4-D has been found to be widespread in microbial communities around the globe. Functional genes involved in the degradation pathway have also been characterised. Thus, 2,4-D represents a very suitable model compound to use in order to gain an insight into pollutant degradation dynamics in the rapidly changing Arctic region. We collected surface ice cores on the GrIS and incubated them for up to 529 days in microcosms simulating in situ conditions. We measured mineralisation of side-chain- and ring-labelled 14C-2,4-D in the samples and performed quantitative PCR targeting the tfdA gene, encoding an enzyme catalysing the first step in the degradation pathway of 2,4-D, in the DNA extracted from the ice after the experiments. We show that the microbial community on the surface of the GrIS is of low diversity, but contains microbes capable of degrading 2,4-D. The low diversity of the community and the similarity of the detected clones to those from other icy environment clones suggest that the bacterial community on the GrIS is selected from a pool of propagules deposited on the surface of the ice sheet, based on the level of adaptation to the conditions in the surface ice. The 2,4-D degraders are likely present in very low numbers, and they can mineralise 2,4-D at a rate of up to 1 nmol per m2 per day, equivalent to ~26 ng C m-2 d-1. We contend that the surface of the GrIS should not be considered to be a mere reservoir of all atmospheric contaminants, as it is likely that some deposited compounds will be removed from the system via biodegradation processes before their potential release due to the accelerated melting of the ice sheet.

Stibal, M.; Bćlum, J.; Holben, W. E.; Jacobsen, C. S.

2012-12-01

179

Understanding the Causes of Spatial Variation in Pesticide Sorption and  

E-print Network

1 Understanding the Causes of Spatial Variation in Pesticide Sorption and Degradation: Abdul Ghafoor) #12;Understanding the causes of spatial variation in pesticide degradation and sorption crop yields, present particular risks to soil and water resources which sustain life. Degradation

180

Routine low-level monitoring of polar pesticides and pesticide degradates by HPLC/ESI-MS: Evaluating long-term performance  

USGS Publications Warehouse

The sensitivity and selective determination of polar pesticides were analyzed using high-performance liquid chromatography/electrospray ionization-mass spectrometry (HPLC/ESI-MS). The effects of multiple operators and instruments on method performance were evaluated using 440 pairs of fortified reagent-water and blank reagent-water samples. The influence of varying environmental matrices on recovery and precision were also analyzed using 200 fortified ambient water samples and duplicate ambient water samples. The results show that compound stability in filtered water was matrix-, chemical class- and compound-dependent which ranged from 1 day to 2 weeks.

Furlong, E.T.; Martin, J.D.; Werner, S.L.; Gates, P.M.

2002-01-01

181

Neonicotinoid pesticide reduces bumble bee colony growth and queen production.  

PubMed

Growing evidence for declines in bee populations has caused great concern because of the valuable ecosystem services they provide. Neonicotinoid insecticides have been implicated in these declines because they occur at trace levels in the nectar and pollen of crop plants. We exposed colonies of the bumble bee Bombus terrestris in the laboratory to field-realistic levels of the neonicotinoid imidacloprid, then allowed them to develop naturally under field conditions. Treated colonies had a significantly reduced growth rate and suffered an 85% reduction in production of new queens compared with control colonies. Given the scale of use of neonicotinoids, we suggest that they may be having a considerable negative impact on wild bumble bee populations across the developed world. PMID:22461500

Whitehorn, Penelope R; O'Connor, Stephanie; Wackers, Felix L; Goulson, Dave

2012-04-20

182

Surface detection of chemical warfare agent simulants and degradation products  

Microsoft Academic Search

Chemical warfare agent (CWA) simulants as well as their degradation and hydrolysis products were detected from surfaces using thermal desorption ion mobility spectrometry (TD-IMS). CWA simulant materials that closely mimic the chemical structures of real CWA G\\/V-type nerve and S-type vesicant simulants were used in this study. Reduced mobility constants (K0) in air were reported for 20 compounds studied. Spectra

Abu B. Kanu; Paul E. Haigh; Herbert H. Hill

2005-01-01

183

Comparative aspects of pesticide metabolism in plants and animals.  

PubMed Central

Pesticide chemicals are an important component of modern agriculture. Through their use, plants and animals are exposed to pesticides directly and indirectly from transport through soil, water, and other environmental components. Pesticide chemicals which are absorbed by plants and animals undergo extensive biotransformation. Lipophilic compounds are converted to polar metabolites through a variety of microsomal and extramicrosomal reactions in plants and animals. Generally, biotransformations are qualitatively similar in both systems. However, there are important quantitative rate differences in metabolism which often determine the balance between activation and deactivation of a pesticide. Furthermore, there are qualitative differences in conjugative mechanisms in plants and animals. Animals through an efficient excretory system eliminate transformation products via the urine and feces. Since efficient excretory systems are absent in plants, terminal degradation products are stored as conjugates and/or derivatives which may be incorporated into the plants themselves. Metabolic transformations of selected pesticides illustrating various types of reactions in plants and animals are discussed. PMID:367763

Menn, J J

1978-01-01

184

Bees and Pesticides  

Microsoft Academic Search

Honey bees (Apis mellifera L.) are the main pollinating agents for numerous plants and fruit trees and hence, play a key role in agriculture and more generally in the maintenance of ecological biodiversity. They are mostly affected farm animals by pesticides. Indeed, pesticides work in two ways to reduce bee populations. First, many pesticides used in crop production are highly

Róbert Chlebo

2006-01-01

185

ANALYTICAL METHOD DEVELOPMENT FOR ALACHLOR ESA AND OTHER ACETANILIDE HERBICIDE DEGRADATION PRODUCTS  

EPA Science Inventory

In 1998, USEPA published a Drinking Water Contaminant Candidate List (CCL) of 50 chemicals and 10 microorganisms. "Alachlor ESA and other acetanilide herbicide degradation products" is listed on the the 1998 CCL. Acetanilide degradation products are generally more water soluble...

186

Maleimides in recent sediments Using chlorophyll degradation products for palaeoenvironmental reconstructions  

E-print Network

Maleimides in recent sediments ­ Using chlorophyll degradation products for palaeoenvironmental online 12 June 2013 Abstract Maleimides (transformation products of chlorophylls and bacteriochlorophylls to investigate chlorophyll degradation, the role of oxygen in maleimide formation, and to identify their sources

Wehrli, Bernhard

187

Halotolerance, ligninase production and herbicide degradation ability of basidiomycetes strains.  

PubMed

Fungi have been recently recognized as organisms able to grow in presence of high salt concentration with halophilic and halotolerance properties and their ligninolytic enzyme complex have an unspecific action enabling their use to degradation of a number of xenobiotic compounds. In this work, both the effect of salt and polyols on growth of the basidiomycetes strains, on their ability to produce ligninolytic enzyme and diuron degradation were evaluated. Results showed that the presence of NaCl in the culture medium affected fungal specimens in different ways. Seven out of ten tested strains had growth inhibited by salt while Dacryopinax elegans SXS323, Polyporus sp MCA128 and Datronia stereoides MCA167 fungi exhibited higher biomass production in medium containing 0.5 and 0.6 mol.L(-1) of NaCl, suggesting to be halotolerant. Polyols such as glycerol and mannitol added into the culture media improved the biomass and ligninases production by D. elegans but the fungus did not reveal consumption of these polyols from media. This fungus degraded diuron in medium control, in presence of NaCl as well as polyols, produced MnP, LiP and laccase. PMID:24688513

Arakaki, R L; Monteiro, D A; Boscolo, M; Dasilva, R; Gomes, E

2013-12-01

188

40 CFR 152.8 - Products that are not pesticides because they are not for use against pests.  

Code of Federal Regulations, 2013 CFR

...defined in § 152.5, if it is: (a) A fertilizer product not containing a pesticide. (b) A product intended to force bees from hives for the collection of honey crops. [53 FR 15975, May 4, 1988, as amended at 66 FR 64764, Dec. 14,...

2013-07-01

189

40 CFR 152.8 - Products that are not pesticides because they are not for use against pests.  

Code of Federal Regulations, 2012 CFR

...defined in § 152.5, if it is: (a) A fertilizer product not containing a pesticide. (b) A product intended to force bees from hives for the collection of honey crops. [53 FR 15975, May 4, 1988, as amended at 66 FR 64764, Dec. 14,...

2012-07-01

190

Community air monitoring for pesticides. Part 3: using health-based screening levels to evaluate results collected for a year.  

PubMed

The CA Department of Pesticide Regulation (CDPR) and the CA Air Resources Board monitored 40 pesticides, including five degradation products, in Parlier, CA, to determine if its residents were exposed to any of these pesticides and, if so, in what amounts. They included 1,3-dichloropropene, acrolein, arsenic, azinphos-methyl, carbon disulfide, chlorpyrifos and its degradation product, chlorthalonil, copper, cypermethrin, diazinon and its degradation product, dichlorvos, dicofol, dimethoate and its degradation product, diuron, endosulfan and its degradation product, S-ethyl dipropylcarbamothioate (EPTC), formaldehyde, malathion and its degradation product, methyl isothiocyanate (MITC), methyl bromide, metolachlor, molinate, norflurazon, oryzalin, oxyfluorfen, permethrin, phosmet, propanil, propargite, simazine, SSS-tributylphosphorotrithioate, sulfur, thiobencarb, trifluralin, and xylene. Monitoring was conducted 3 days per week for a year. Twenty-three pesticides and degradation products were detected. Acrolein, arsenic, carbon disulfide, chlorpyrifos, copper, formaldehyde, methyl bromide, MITC, and sulfur were detected in more than half the samples. Since no regulatory ambient air standards exist for these pesticides, CDPR developed advisory, health-based non-cancer screening levels (SLs) to assess acute, subchronic, and chronic exposures. For carcinogenic pesticides, CDPR assessed risk using cancer potency values. Amongst non-carcinogenic agricultural use pesticides, only diazinon exceeded its SL. For carcinogens, 1,3-dichloropropene concentrations exceeded its cancer potency value. Based on these findings, CDPR has undertaken a more comprehensive evaluation of 1,3-dichloropropene, diazinon, and the closely related chlorpyrifos that was frequently detected. Four chemicals-acrolein, arsenic, carbon disulfide, and formaldehyde-sometimes used as pesticides were detected, although no pesticidal use was reported in the area during this study. Their presence was most likely due to vehicular or industrial emissions. PMID:24370859

Wofford, Pamela; Segawa, Randy; Schreider, Jay; Federighi, Veda; Neal, Rosemary; Brattesani, Madeline

2014-03-01

191

The Greening of Pesticide–Environment Interactions: Some Personal Observations  

PubMed Central

Background: Pesticide–environment interactions are bidirectional. The environment alters pesticides by metabolism and photodegradation, and pesticides in turn change the environment through nontarget or secondary effects. Objectives: Approximately 900 currently used commercial pesticides of widely diverse structures act by nearly a hundred mechanisms to control insects, weeds, and fungi, usually with minimal disruption of nature’s equilibrium. Here I consider some aspects of the discovery, development, and use of ecofriendly or green pesticides (i.e., pesticides that are safe, effective, and biodegradable with minimal adverse secondary effects on the environment). Emphasis is given to research in my laboratory. Discussion: The need for understanding and improving pesticide–environment interactions began with production of the first major insecticide approximately 150 years ago: The arsenical poison Paris Green was green in color but definitely not ecofriendly. Development and use of other pesticides has led to a variety of problems. Topics considered here include the need for high purity [e.g., hexachlorocyclohexane and polychloroborane isomers and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)], environmental degradation and the bioactivity of resulting photoproducts and metabolites, pesticide photochemistry (including the use of structural optimization, photostabilizers, and photosensitizers to achieve suitable persistence), the presence of multiple active ingredients in botanical insecticides, the need to consider compounds with common mechanisms of action, issues related to primary and secondary targets, and chemically induced or genetically modified changes in plant biochemistry. Many insecticides are bird, fish, and honeybee toxicants, whereas herbicides and fungicides pose fewer environmental problems. Conclusion: Six factors have contributed to the greening of pesticide–environment interactions: advances in pesticide chemistry and toxicology, banning of many chlorinated hydrocarbons, the development of new biochemical targets, increased reliance on genetically modified crops that reduce the amount and variety of pesticides applied, emphasis on biodegradability and environmental protection, and integrated pest- and pesticide-management systems. PMID:22472325

2012-01-01

192

Electrospray ionization mass spectrometry (ESI-MS) monitoring of the photolysis of diazinon in aqueous solution: degradation route and toxicity of by-products against Artemia salina.  

PubMed

The photolytic degradation of diazinon, an organophosphorus pesticide, in aqueous medium under assorted pH values was continuously monitored by direct infusion electrospray ionization mass spectrometry (ESI-MS). The results indicated that the UV radiation was quite efficient in promoting the pesticide degradation at the three pH levels evaluated (5, 7 and 8). The m/z of the most abundant ions observed in the mass spectra (MS), in conjunction with the fragmentation patterns of such ionic species (MS/MS data), made possible the proposition of chemical structures for the main by-products formed. As a result, routes for the photodegradation of diazinon in aqueous solution could thus be suggested. In the assays using Artemia salina (brine shrimp) it was verified that the photodegradation products exhibited much lower toxicity than the primary substrate. Aiming at mimicking the conditions ordinarily found in water treatment plants, an additional series of tests was conducted with a solution containing sodium hypochlorite and diazinon. This solution, when not exposed to UV radiation, exhibited high toxicity against the microorganisms. Under the influence of UV radiation, however, the toxicity rates decreased dramatically. This result is relevant because it points toward the confident application of UV radiation to neutralize the deleterious effects caused by diazinon (and perhaps other organophosphorus pesticides) as well as sodium hypochlorite to the environment. PMID:23356337

Souza, Amauri G; Cardeal, Zenilda L; Augusti, Rodinei

2013-01-01

193

Vibrational spectroscopy for online monitoring of extraction solvent degradation products  

SciTech Connect

In our research, we are exploring the potential of online monitoring of the organic solvents for the flowsheets relevant to the used nuclear fuel reprocessing and tributyl phosphate (TBP)- based extraction processes in particular. Utilization of vibrational spectroscopic techniques permits the discrimination of the degradation products from the primary constituents of the loaded extraction solvent. Multivariate analysis of the spectral data facilitates development of the regression models for their quantification in real time and potentially enables online implementation of a monitoring system. Raman and FTIR spectral databases were created and used to develop the regression partial least squares (PLS) chemometric models for the quantitative prediction of HDBP (dibutyl phosphoric acid) degradation product, TBP, and UO{sub 2}{sup 2+} extraction organic product phase. It was demonstrated that both these spectroscopic techniques are suitable for the quantification of the Purex solvent components in the presence of UO{sub 2}(NO{sub 3}){sub 2}. Developed PLS models successfully predicted HDBP and TBP organic concentrations in simulated Purex solutions.

Peterson, J.; Robinson, T.; Bryan, S.A.; Levitskaia, T.G. [Pacific Northwest National Laboratory, 902 Battelle Blvd, PO Box 999, MSIN P7-25 Richland, WA 99352 (United States)

2013-07-01

194

Overview of potential mutagenic problems posed by some pesticides and their trace impurities.  

PubMed Central

This review principally addresses a number of aspects of usage of pesticides as well as populations at potential risk and attempts to highlight categories of pesticides whose structures or those of their metabolites and/or trace impurities, degradation and transformation products suggest an a priori mutagenic and/or carcinogenic risk. The pesticides considered include: DDT, hexachlorobenzene (HCB), 2,4,5-T, pentachlorophenol, and various herbicidal precursors (e.g., carbamates, triazines) of nitrosamines and nitroso derivatives. Structural features of a number of halo-unsaturated pesticides (e.g., dichloropropenes) were also reviewed from a viewpoint of contrasting their potential mutagenicity with that of vinyl chloride and vinylidene chloride. Additionally the mutagenicity of the organophosphorus pesticide Trichlorophon is contrasted with that of its degradation products. PMID:367764

Fishbein, L

1978-01-01

195

Safe apples for baby-food production: survey of pesticide treatment regimes leaving minimum residues.  

PubMed

A total of 19 pesticide preparations were used according to agricultural practice in six trials in apple orchards. Using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), premature Golden Delicious apples collected 64, 50, 36 days before harvest and mature fruit were examined for residues of active ingredients. No residues of triflumuron, triazamate, chlorpyrifos, etofenprox, fenoxycarb, kresoxim-methyl, cyprodinyl, difenoconazole or thiram were detected in the first sampling. Also, the levels of chlorpyrifos-methyl, penconazole, tebuconazole and tolylfluanid dropped during the pre-harvest interval. Detectable residues of pyridaben, thiacloprid, trifloxystrobin and tetraconazole in harvested fruits were below 0.01 mg kg(-1), which is the maximum concentration of residues acceptable by baby-food producers in any raw material. The only residues exceeding this concentration were captan and teflubenzuron. Based on the data, farmers can choose pesticides for optimal treatment of plants, while enabling growth of a safe crop suitable for baby-food production. PMID:17487602

Ticha, Jana; Hajslova, Jana; Kovalczuk, Tomas; Jech, Martin; Honzicek, Jiri; Kocourek, Vladimir; Lansky, Miroslav; Kloutvorova, Jana; Falta, Vladan

2007-06-01

196

Antimicrobial Pesticides  

NSDL National Science Digital Library

This newly launched site from the US Environmental Protection Agency (EPA) offers a variety of resources describing how the EPA regulates antimicrobial pesticides. Antimicrobial pesticides are used in a huge variety of household and commercial products to "disinfect, sanitize, reduce, or mitigate growth or development of microbiological organisms" and to "protect inanimate objects (for example floors and walls), industrial processes or systems, surfaces, water, or other chemical substances from contamination, fouling, or deterioration caused by bacteria, viruses, fungi, protozoa, algae, or slime." Intended mainly for a regulatory audience, the site includes Antimicrobials Science Policy Documents, Antimicrobials Registration Policy Documents, Label Review Manual, Chemical/ Registration Number Indexes, and Antimicrobial PR notices.

197

The investigation of the LED-activated FeFNS-TiO2 nanocatalyst for photocatalytic degradation and mineralization of organophosphate pesticides in water.  

PubMed

This study evaluated the preparation and characterization of an efficient doped TiO2 as a novel catalyst for degradation of diazinon model pesticide using LED-activated photocatalysis. TiO2 was doped using N, NS, FeNS, and FeFNS. The FeFNS-doped TiO2 showed the highest catalytic activity in LED/photocatalysis. FeFNS-doped TiO2 is a mesoporous nanocrystal powder with a mean pore diameter of 10.2 nm, a specific surface area of 104.4 m(2)/g and a crystallite size of 6.7 nm. LED/photocatalysis using FeFNS-doped TiO2 improved diazinon degradation by 52.3% over that of as-made plain TiO2 at an optimum solution pH of 7. The diazinon degradation in LED/photocatalysis using FeFNS-doped TiO2 increased from 44.8% to 96.3% when the catalyst concentration increased from 25% to 300%at a reaction time of 100 min. The degradation and mineralization of diazinon during LED/photocatalysis with FeFNS-doped TiO2 catalyst followed the pseudo-first-order reaction model with the rate constants of 0.973 h(-1) and 0.541 h(-1), respectively. The FeFNS-doped TiO2 was found to be an efficient catalyst that was photoactivated using UV-LED lamps. LED/photocatalysis with FeFNS-doped TiO2 catalyst is a promising alternative to conventional UV/TiO2photocatalysis for producing free OH radicals for use in the degradation and mineralization of water toxic contaminants. PMID:24793111

Hossaini, Hiwa; Moussavi, Gholamreza; Farrokhi, Mehrdad

2014-08-01

198

Relationship between bacterial diversity and function under biotic control: the soil pesticide degraders as a case study  

PubMed Central

In soil, the way biotic parameters impact the relationship between bacterial diversity and function is still unknown. To understand these interactions better, we used RNA-based stable-isotope probing to study the diversity of active atrazine-degrading bacteria in relation to atrazine degradation and to explore the impact of earthworm-soil engineering with respect to this relationship. Bulk soil, burrow linings and earthworm casts were incubated with 13C-atrazine. The pollutant degradation was quantified by liquid chromatography–mass spectrometry for 8 days, whereas active atrazine degraders were identified at 2 and 8 days by sequencing the 16S ribosomal RNA in the 13C-RNA fractions from the three soil microsites. An original diversity of atrazine degraders was found. Earthworm soil engineering greatly modified the taxonomic composition of atrazine degraders with dominance of ?-, ?- and ?-proteobacteria in burrow linings and of Actinobacteria in casts. Earthworm soil bioturbation increased the ?-diversity of atrazine degraders over the soil microsites generated. Atrazine degradation was enhanced in burrow linings in which primary atrazine degraders, closely related to Pelomonas aquatica, were detected only 2 days after atrazine addition. Atrazine degradation efficiency was not linearly related to the species richness of degraders but likely relied on keystone species. By enhancing soil heterogeneity, earthworms sustained high phylogenetic bacterial diversity and exerted a biotic control on the bacterial diversity–function relationships. Our findings call for future investigations to assess the ecological significance of biotic controls on the relationships between diversity and function on ecosystem properties and services (for example, soil detoxification) at larger scales. PMID:21160539

Monard, Cecile; Vandenkoornhuyse, Philippe; Le Bot, Barbara; Binet, Francoise

2011-01-01

199

College of Agricultural Sciences Cooperative Extension Pesticide Education  

E-print Network

College of Agricultural Sciences Cooperative Extension Pesticide Education Pesticide Storage need to be aware of proper pesticide storage practices. An important issue of safe storage or environmental damage. Always consult the pesticide product label and MSDS for specific storage information

Kaye, Jason P.

200

Molecularly imprinted polymer-based potentiometric sensor for degradation product of chemical warfare agents. Part I. Methylphosphonic acid.  

PubMed

A biomimetic potentiometric sensor for the specific recognition of methylphosphonic acid (MPA), the degradation product of nerve agents sarin, soman, VX, etc., was designed. This involves the preparation of MPA imprinted polymer particles and removal of the template by soxhlet extraction. Subsequently, the leached MIP particles were dispersed in 2-nitrophenyloctyl ether (plasticizer) and embedded in polyvinyl chloride matrix. The sensor responds to MPA in the concentration range 5x10(-8) to 1x10(-4) and 1x10(-3) to 1x10(-1)M with a detection limit of 5x10(-8)M. The selectivity of the sensor has been tested with respect to chemical analogues such as phosphoric acid, sodium dihydrogen phosphate, organophosphorous pesticide and triazine herbicides. The utility of the sensor was tested for field monitoring of MPA in spiked ground water. PMID:19071551

Prathish, K P; Prasad, K; Rao, T Prasada; Suryanarayana, M V S

2007-03-30

201

Pesticide Record Keeping Requirements For New Hampshire  

E-print Network

Pesticide Record Keeping Requirements For New Hampshire Pesticide applicators are required to maintain records on pesticide applications according to state and national regulations. Also pesticide or solve production problems. This fact sheet will help you comply with federal and state pesticide record

New Hampshire, University of

202

Modeling Degradation Product Partitioning in Chlorinated-DNAPL Source Zones  

NASA Astrophysics Data System (ADS)

Metabolic reductive dechlorination degrades aqueous phase contaminant concentrations, increasing the driving force for DNAPL dissolution. Results from laboratory and field investigations suggest that accumulation of cis-dichloroethene (cis-DCE) and vinyl chloride (VC) may occur within DNAPL source zones. The lack of (or slow) degradation of cis-DCE and VC within bioactive DNAPL source zones may result in these dechlorination products becoming distributed among the solid, aqueous, and organic phases. Partitioning of cis-DCE and VC into the organic phase may reduce aqueous phase concentrations of these contaminants and result in the enrichment of these dechlorination products within the non-aqueous phase. Enrichment of degradation products within DNAPL may reduce some of the advantages associated with the application of bioremediation in DNAPL source zones. Thus, it is important to quantify how partitioning (between the aqueous and organic phases) influences the transport of cis-DCE and VC within bioactive DNAPL source zones. In this work, abiotic two-phase (PCE-water) one-dimensional column experiments are modeled using analytical and numerical methods to examine the rate of partitioning and the capacity of PCE-DNAPL to reversibly sequester cis-DCE. These models consider aqueous-phase, nonaqueous phase, and aqueous plus nonaqueous phase mass transfer resistance using linear driving force and spherical diffusion expressions. Model parameters are examined and compared for different experimental conditions to evaluate the mechanisms controlling partitioning. Biot number, a dimensionless number which is an index of the ratio of the aqueous phase mass transfer rate in boundary layer to the mass transfer rate within the NAPL, is used to characterize conditions in which either or both processes are controlling. Results show that application of a single aqueous resistance is capable to capture breakthrough curves when DNAPL is distributed in porous media as low-saturation ganglia, while diffusion within the DNAPL should be considered for larger NAPL pools. These results offer important insights to the monitoring and interpretation of bioremediation strategies employed within DNAPL source zones.

Boroumand, A.; Ramsburg, A.; Christ, J.; Abriola, L.

2009-12-01

203

Degradation and transformation products of acetaminophen in soil.  

PubMed

Acetaminophen is the most widely used human medicine. Trace levels of acetaminophen are frequently detected in treated wastewater and the impacted surface or groundwater resources. However, even though soil is a primary receiving compartment, the fate of acetaminophen in soil is poorly known, including in particular the potential for the formation of incomplete degradation products that may have altered biological activity and mobility. In this study, using both (14)C-labeling and LC-MS/MS techniques, we evaluated the dissipation routes and transformation pathways of acetaminophen in soils under a range of conditions. Throughout 120-d aerobic incubation, up to 17.0 ± 0.8% of (14)C-acetaminophen was mineralized, but mineralization was greatly inhibited after sterilization or amendment of biosolids. Immediately after treatment, the majority of (14)C-residue became non-extractable or bound, with the level accounting for 73.4-93.3% of the applied amount at the end of incubation. A total of 8 intermediates were identified, including 3-hydroxyacetaminophen, hydroquinone, 1, 4-benzoquinone, N-acetyl-p-benzoquinone imine, p-acetanisidide, 4-methoxyphenol, 2-hexenoic acid, and 1, 4-dimethoxybenzene. Mineralization and rapid conversion to bound residues suggest that acetaminophen is quickly detoxified in soil, decreasing the potential for off-site transport such as leaching or runoff. On the other hand, the formation of a large number of degradation intermediates, and their potential biological activity, may pose unknown risks, such as accumulation into edible plants. This risk warrants further investigation. PMID:24316789

Li, Juying; Ye, Qingfu; Gan, Jay

2014-02-01

204

Toxicology of atmospheric degradation products of selected hydrochlorofluorocarbons  

NASA Technical Reports Server (NTRS)

Trifluoroacetic acid (TFA) is a liquid with a sharp biting odor. It has been proposed as the product of environmental degradation of the hydrochlorofluorocarbons HCFC-123, HCFC-124, HFC-134a, and HFC-125. Compounds HCFC-141b and HCFC-142b could yield mixed fluorochloroacetic acids, for which there is no available toxicologic data. The release of hydrochlorofluorocarbons into the environment could also give rise to HF, but the additional fluoride burden (1 to 3 ppb) in rainwater is trivial compared to levels in fluoridated drinking water (1 ppm), and would provide an insignificant risk to humans. Thus, in this paper only the toxocologic data on TFA is reviewed to assess the potential risks of environmental exposure.

Kaminsky, Laurence S.

1990-01-01

205

Enzymatic degradation of plutonium-contaminated cellulose products  

SciTech Connect

Enzyme solutions produced for commercial purposes unrelated to waste management have the potential for reducing the volume of wastes in streams containing cellulose, lipid and protein materials. For example, the authors have shown previously that cellulases used in denim production and in detergent formulations are able to digest cellulose-containing sorbents and other cellulose-based wastes contaminated either with crude oil or with uranium. This presentation describes the use of one such enzyme preparation (Rapidase{trademark}, manufactured by Genencor, Rochester, NY) for the degradation of cotton sorbents intentionally contaminated with low levels of plutonium. This is part of a feasibility study to determine if such treatments have a role in reducing the volume of low level and transuranic wastes to minimize the amount of radionuclide-contaminated waste destined for costly disposal options.

Heintz, C.E.; Rainwater, K.A.; Swift, L.M. [Texas Tech Univ., Lubbock, TX (United States); Barnes, D.L. [Amarillo National Resource Center for Plutonium, TX (United States); Worl, L.A. [Los Alamos National Lab., NM (United States)

1999-06-01

206

Variation in pesticide hazard from arable crop production in Great Britain from 1992 to 2002: Pesticide risk indices and policy analysis  

Microsoft Academic Search

Attempts to direct policy according to scientific findings are hampered by the multidimensionality of the potential impacts of pesticides which may affect consumers, operators, wildlife and the environment. Pesticide risk indices seek to reduce these multidimensional impacts to a single dimension and are increasingly used to understand variation in the hazard inherent in pesticides at the farm, regional and national

Paul Cross; Gareth Edwards-Jones

2006-01-01

207

Production of degradable polymers from food-waste streams  

SciTech Connect

In the United States, billions of pounds of cheese whey permeate and approximately 10 billion pounds of potatoes processed each year are typically discarded or sold as cattle feed at $3{endash}6/ton; moreover, the transportation required for these means of disposal can be expensive. As a potential solution to this economic and environmental problem, Argonne National Laboratory is developing technology that: Biologically converts existing food-processing waste streams into lactic acid and uses lactic acid for making environmentally safe, degradable polylactic acid (PLA) and modified PLA plastics and coatings. An Argonne process for biologically converting high-carbohydrate food waste will not only help to solve a waste problem for the food industry, but will also save energy and be economically attractive. Although the initial substrate for Argonne's process development is potato by-product, the process can be adapted to convert other food wastes, as well as corn starch, to lactic acid. Proprietary technology for biologically converting greater than 90% of the starch in potato wastes to glucose has been developed. Glucose and other products of starch hydrolysis are subsequently fermented by bacteria that produce lactic acid. The lactic acid is recovered, concentrated, and further purified to a polymer-grade product.

Tsai, S.P.: Coleman, R.D.; Bonsignore, P.V.; Moon, S.H.

1992-01-01

208

Production of degradable polymers from food-waste streams  

SciTech Connect

In the United States, billions of pounds of cheese whey permeate and approximately 10 billion pounds of potatoes processed each year are typically discarded or sold as cattle feed at $3{endash}6/ton; moreover, the transportation required for these means of disposal can be expensive. As a potential solution to this economic and environmental problem, Argonne National Laboratory is developing technology that: Biologically converts existing food-processing waste streams into lactic acid and uses lactic acid for making environmentally safe, degradable polylactic acid (PLA) and modified PLA plastics and coatings. An Argonne process for biologically converting high-carbohydrate food waste will not only help to solve a waste problem for the food industry, but will also save energy and be economically attractive. Although the initial substrate for Argonne`s process development is potato by-product, the process can be adapted to convert other food wastes, as well as corn starch, to lactic acid. Proprietary technology for biologically converting greater than 90% of the starch in potato wastes to glucose has been developed. Glucose and other products of starch hydrolysis are subsequently fermented by bacteria that produce lactic acid. The lactic acid is recovered, concentrated, and further purified to a polymer-grade product.

Tsai, S.P.: Coleman, R.D.; Bonsignore, P.V.; Moon, S.H.

1992-07-01

209

EU Food Safety Standards, Pesticide Use and Farm-level Productivity: The Case of High-value Crops in Kenya  

Microsoft Academic Search

This article provides an empirical analysis of the impact of European Union (EU) private food safety standards on pesticide use and farm-level productivity among small-scale vegetable producers in Kenya. We apply an extended three-stage damage control production framework, accounting for multiple endogeneity problems, to farm-level data collected from a random cross-sectional sample of 539 small-scale producers. Estimation results show that

Solomon Asfaw; Dagmar Mithöfer; Hermann Waibel

2009-01-01

210

Selectivity of Pesticides used in Integrated Apple Production to the Lacewing, Chrysoperla externa  

PubMed Central

This research aimed to assess the toxicity of the pesticides abamectin 18 CE (0.02 g a.i. L-1), carbaryl 480 SC (1.73 g a.i. L-1), sulfur 800 GrDA (4.8 g a.i. L-1), fenitrothion 500 CE (0.75 g a.i. L-1), methidathion 400 CE (0.4 g a.i. L-1), and trichlorfon 500 SC (1.5 g a.i. L-1) as applied in integrated apple production in Brazil on the survival, oviposition capacity, and egg viability of the lacewing, Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) from Bento Gonçalves and Vacaria, Rio Grande do Sul State, Brazil. An attempt was made to study morphological changes caused by some of these chemicals, by means of ultrastructural analysis, using a scanning electronic microscope. Carbaryl, fenitrothion, and methidathion caused 100% adult mortality for both populations, avoiding evaluation of pesticides' effects on predator reproductive parameters. Abamectin and sulfur also affected the survival of these individuals with mortality rates of 10% and 6.7%, respectively, for adults from Bento Gonçalves, and were harmless to those from Vacaria at the end of evaluation. Trichlorfon was also harmless to adults from both populations. No compound reduced oviposition capacity. C. externa from Vacaria presented higher reproductive potential than those from Bento Gonçalves. In relation to egg viability, sulfur was the most damaging compound to both populations of C. externa. Ultrastructural analyses showed morphological changes in the micropyle and the chorion of eggs laid by C. externa treated with either abamectin or sulfur. The treatment may have influenced the fertilization of C. externa eggs and embryonic development. Sulfur was responsible for malformations in the end region of the abdomen and genitals of treated females. When applied to adults, abamectin, sulfur, and trichlorfon were harmless, while carbaryl, fenitrothion, and methidathion were harmful, according to the IOBC classification. PMID:20879916

Moura, Alexandre Pinho; Carvalho, Geraldo Andrade; Moscardini, Valeria Fonseca; Lasmar, Olinto; Rezende, Denise Tourino; Marques, Marcio Candeias

2010-01-01

211

Multiresidue method for the fast determination of pesticides in nutraceutical products (Camellia sinensis) by GC coupled to triple quadrupole MS.  

PubMed

A method based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) has been developed and validated for the determination and quantification of more than 140 pesticides in nutraceutical products obtained from green tea (Camellia sinensis). Extraction was performed with acidified acetonitrile (acetic acid 1%, v/v) and a clean-up step using primary secondary amine (50 mg), graphitized black carbon (100 mg) and magnesium sulfate (200 mg) was needed. Pesticide determination was achieved utilizing GC coupled to triple quadrupole MS/MS using the selective-reaction monitoring mode. The total run time was 23 min. Pesticides were quantified using matrix-matched calibration. Recoveries ranged from 70 to 120% and relative SD was lower than 25% at 10, 50, and 100 ?g/kg. LOQs were lower than 10 ?g/kg. 148 pesticides were validated. The validated method was applied to commercial nutraceutical products, detecting 4,4-dichlorobenzophenone (28 ?g/kg), o,p'-dicofol (38 ?g/kg) and p,p-dicofol (44 ?g/kg) in a few samples. PMID:24532456

Martínez-Domínguez, Gerardo; Plaza-Bolańos, Patricia; Romero-González, Roberto; Frenich, Antonia Garrido

2014-03-01

212

Micronuclei and pesticide exposure.  

PubMed

Micronucleus (MN) is a biomarker widely used in biomonitoring studies carried out to determine the genetic risk associated to pesticide exposure. Many in vitro and in vivo studies, as well as epidemiological approaches, have demonstrated the ability of certain chemical pesticides to produce genetic effects including cancer and other chronic pathologies in humans; thus, biomonitoring studies have been carried out to characterise the genetic risk associated to pesticide exposure. It must be noted that 'pesticide exposure' is a broad term covering complex mixtures of chemicals and many variables that can reduce or potentiate their risk. In addition, there are large differences in pesticides used in the different parts of the world. Although pesticides constitute a wide group of environmental pollutants, the main focus on their risk has been addressed to people using pesticides in their working places, at the chemical industry or in the crop fields. Here, we present a brief review of biomonitoring studies carried out in people occupationally exposed to pesticides and that use MN in lymphocytes or buccal cells as a target to determine the induction of genotoxic damage. Thus, people working in the chemical industry producing pesticides, people spraying pesticides and people dedicated to floriculture or agricultural works in general are the subject of specific sections. MN is a valuable genotoxic end point when clear exposure conditions exist like in pesticide production workers; nevertheless, better study designs are needed to overcome the uncertainty in exposure, genetic susceptibility and statistical power in the studies of sprayers and floriculture or agricultural workers. PMID:21164178

Bolognesi, Claudia; Creus, Amadeu; Ostrosky-Wegman, Patricia; Marcos, Ricard

2011-01-01

213

Pesticide residue free fruits: the aim of Trentino apple production system.  

PubMed

Chemical analyses performed in 2011 on the 575 samples of apples in Trentino (Italy), there are in average 3.24 active ingredient per sample. Moreover, in 98% of the samples with detectable residues, the level did not exceed 30% of the official MRL This result is achieved thanks to the implementation of the guide lines for integrated production by the 8000 fruit growers, to an extension service which justifies the need of the treatment and gives advice on which pesticide fit better for the time-pest combination, to the systematic check up of the sprayers, to the correct sizing of mix volumes to spray according to the size of the canopy, to the selection of active ingredients based on their residual activity in field tests, and to the systematic monitoring of the level of residues found on representative samples of the product at harvest. With these assumptions, the next goal is to eliminate all traces of insecticides and acaricides now present only in 30% of the samples. This aim could be achieved by extending the use of pheromone mating disruption to control fruit feeding Lepidoptera, as well as by promoting the use of short persistent residue products during the final part of the season. Results of some of the experimental field trials are presented and discussed. PMID:25145233

Baldessari, M; Giuliani, G; Chiesa, S; Larcher, R; Ioriatti, C; Angeli, G

2013-01-01

214

Pesticide Flow Analysis to Assess Human Exposure in Greenhouse Flower Production in Colombia  

PubMed Central

Human exposure assessment tools represent a means for understanding human exposure to pesticides in agricultural activities and managing possible health risks. This paper presents a pesticide flow analysis modeling approach developed to assess human exposure to pesticide use in greenhouse flower crops in Colombia, focusing on dermal and inhalation exposure. This approach is based on the material flow analysis methodology. The transfer coefficients were obtained using the whole body dosimetry method for dermal exposure and the button personal inhalable aerosol sampler for inhalation exposure, using the tracer uranine as a pesticide surrogate. The case study was a greenhouse rose farm in the Bogota Plateau in Colombia. The approach was applied to estimate the exposure to pesticides such as mancozeb, carbendazim, propamocarb hydrochloride, fosetyl, carboxin, thiram, dimethomorph and mandipropamide. We found dermal absorption estimations close to the AOEL reference values for the pesticides carbendazim, mancozeb, thiram and mandipropamide during the study period. In addition, high values of dermal exposure were found on the forearms, hands, chest and legs of study participants, indicating weaknesses in the overlapping areas of the personal protective equipment parts. These results show how the material flow analysis methodology can be applied in the field of human exposure for early recognition of the dispersion of pesticides and support the development of measures to improve operational safety during pesticide management. Furthermore, the model makes it possible to identify the status quo of the health risk faced by workers in the study area. PMID:23528812

Lesmes-Fabian, Camilo; Binder, Claudia R.

2013-01-01

215

Pesticide flow analysis to assess human exposure in greenhouse flower production in Colombia.  

PubMed

Human exposure assessment tools represent a means for understanding human exposure to pesticides in agricultural activities and managing possible health risks. This paper presents a pesticide flow analysis modeling approach developed to assess human exposure to pesticide use in greenhouse flower crops in Colombia, focusing on dermal and inhalation exposure. This approach is based on the material flow analysis methodology. The transfer coefficients were obtained using the whole body dosimetry method for dermal exposure and the button personal inhalable aerosol sampler for inhalation exposure, using the tracer uranine as a pesticide surrogate. The case study was a greenhouse rose farm in the Bogota Plateau in Colombia. The approach was applied to estimate the exposure to pesticides such as mancozeb, carbendazim, propamocarb hydrochloride, fosetyl, carboxin, thiram, dimethomorph and mandipropamide. We found dermal absorption estimations close to the AOEL reference values for the pesticides carbendazim, mancozeb, thiram and mandipropamide during the study period. In addition, high values of dermal exposure were found on the forearms, hands, chest and legs of study participants, indicating weaknesses in the overlapping areas of the personal protective equipment parts. These results show how the material flow analysis methodology can be applied in the field of human exposure for early recognition of the dispersion of pesticides and support the development of measures to improve operational safety during pesticide management. Furthermore, the model makes it possible to identify the status quo of the health risk faced by workers in the study area. PMID:23528812

Lesmes-Fabian, Camilo; Binder, Claudia R

2013-04-01

216

Aqueous acetonitrile extraction for pesticide residue analysis in agricultural products with HPLC-DAD.  

PubMed

To reduce hazardous organic solvent consumption during sample preparation procedures as much as possible, an extraction method of smallest feasible sample volume (5g) using aqueous acetonitrile (MeCN) was developed to extract pesticide residues from agricultural samples prior to HPLC-DAD determination. Extraction with MeCN/water (1:1, v/v), and adjustment of the MeCN concentration by diluting with water after extraction recovered successfully most pesticides showing various physicochemical properties. The matrix effects of tested samples on the proposed method developed herein were generally negligibly-small. The average recoveries were in the range 70-120% for all pesticides with the coefficient of variation values below 20%. The reduction rate of organic solvents used for the proposed sample preparation method was up to approximately 60% compared with the Japanese authorised official method for pesticide residue analyses. These results demonstrate the feasibility of the proposed method for pesticides with diverse properties. PMID:24518309

Watanabe, Eiki; Kobara, Yuso; Baba, Koji; Eun, Heesoo

2014-07-01

217

The occurrence of glyphosate, atrazine, and other pesticides in vernal pools and adjacent streams in Washington, DC, Maryland, Iowa, and Wyoming, 2005–2006  

Microsoft Academic Search

Vernal pools are sensitive environments that provide critical habitat for many species, including amphibians. These small\\u000a water bodies are not always protected by pesticide label requirements for no-spray buffer zones, and the occurrence of pesticides\\u000a in them is poorly documented. In this study, we investigated the occurrence of glyphosate, its primary degradation product\\u000a aminomethylphosphonic acid, and additional pesticides in vernal

William A. Battaglin; Karen C. Rice; Michael J. Focazio; Sue Salmons; Robert X. Barry

2009-01-01

218

Levels of organochlorine pesticides in crops and related products from Vojvodina, Serbia: estimated dietary intake.  

PubMed

Levels of 16 organochlorine pesticides (OCPs) were investigated in 39 composite samples of agricultural crops, related by-products, and foodstuffs collected in Vojvodina, Serbia, in 2002 through 2004. After extraction and cleanup, OCPs were determined by capillary gas chromatography using electron-capture detection. The highest mean level of 0.971 ng/g whole weight (ww) was found for alpha-HCH in wheat flour samples. OCPs levels were well lower than the respective maximum residue limits set by current European and Serbian regulations. Mean OCP levels were low (<1 ng/g ww) for all sample types. The most frequently determined residue was 4,4'-DDT (identified in 76.9% of all samples analyzed), followed by gamma-HCH (66.7%), beta-HCH (48.7%), and endosulfan II (41.0%). OCP levels were compared with data from other international surveys. Calculated daily intakes of OCPs by way of consumption of the crop products included in this study according to data of the Serbian National Institute for Statistics were compared with the acceptable daily intakes established by the Food and Agriculture Organization/World Health Organization. The average level of contamination of the Vojvodina diet was believed to be harmless regarding the studied food commodities. PMID:18197356

Skrbi?, B; Predojevi?, Z

2008-05-01

219

Long-term clinical effects of a peritoneal dialysis fluid with less glucose degradation products  

Microsoft Academic Search

Long-term clinical effects of a peritoneal dialysis fluid with less glucose degradation products.BackgroundGlucose degradation products (GDPs) are cytotoxic in vitro and potentially toxic in vivo during peritoneal dialysis (PD). We are presenting the results of a two-year randomized clinical trial of a new PD fluid, produced in a two-compartment bag and designed to minimize heat-induced glucose degradation while producing a

Bengt Rippe; Ole Simonsen; Olle Heimbürger; Anders Christensson; Börje Haraldsson; Gunnar Stelin; Lars Weiss; Finn-David Nielsen; Susanne Bro; Michael Friedberg; Anders Wieslander

2001-01-01

220

Reflectance model for quantifying chlorophyll a in the presence of productivity degradation products  

NASA Technical Reports Server (NTRS)

A reflectance model developed to estimate chlorophyll a concentrations in the presence of marine colored dissolved organic matter, pheopigments, detritus, and bacteria is presented. Nomograms and lookup tables are generated to describe the effects of different mixtures of chlorophyll a and these degradation products on the R(412):R(443) and R(443):R(565) remote-sensing reflectance or irradiance reflectance ratios. These are used to simulate the accuracy of potential ocean color satellite algorithms, assuming that atmospheric effects have been removed. For the California Current upwelling and offshore regions, with chlorophyll a not greater than 1.3 mg/cu m, the average error for chlorophyll a retrievals derived from irradiance reflectance data for degradation product-rich areas was reduced from +/-61 percent to +/-23 percent by application of an algorithm using two reflectance ratios rather than the commonly used algorithm applying a single reflectance ratio.

Carder, K. L.; Hawes, S. K.; Steward, R. G.; Baker, K. A.; Smith, R. C.; Mitchell, B. G.

1991-01-01

221

Seasonal exposures to triazine and other pesticides in surface waters in the western Highveld corn-production region in South Africa  

USGS Publications Warehouse

The objective of this study was to characterize concentrations of atrazine, terbuthylazine, and other pesticides in amphibian habitats in surface waters of a corn-production area of the western Highveld region (North-West Province) of South Africa. The study was conducted from November 2001 to June 2002, coinciding with the corn-production season. Pesticide residues were measured at regular intervals in surface water from eight ponds, three in a non-corn-growing area (NCGA) and five within the corn-growing area (CGA). Measured atrazine concentrations differed significantly among sites and between samples. In the five CGA sites, the maximum atrazine concentrations measured during the study ranged from 1.2 to 9.3 ??g/L. Although no atrazine was recorded as being applied in the catchment of the three NCGA sites, maximum concentrations from 0.39 to 0.84 ??g/L were measured during the study, possibly as a result of atmospheric transport. Maximum measured concentrations of terbuthylazine ranged from 1.22 to 2.1 ??g/L in the NCGA sites and from 1.04 to 4.1 ??g/L in the CGA sites. The source of terbuthylazine in the NCGA sites may have been in use other than in corn. The triazine degradation products, deisopropylatrazine (DIA) and deethylatrazine (DEA) and diaminochlorotriazine (DACT) were also found in water from both the CGA and NCGA sites. Concentrations of DIA were ??? 1 ??g/L throughout the season, while DEA concentrations were mostly 2 ??g/L in some locations. Concentrations of DACT were highly variable (LOD to 8 ??g/L) both before and after planting and application, suggesting that they resulted from historical use of triazines in the area. Other herbicides such as simazine and acetochlor were only detected infrequently and pesticides such as S-metolachlor, cypermethrin, monocrotophos, and terbuphos, known to be used in the CGA, were not detected in any of the samples. Because of dilution by higher than normal rainfall in the study period, these concentrations may not be predictive of those in years of normal rainfall. ?? 2004 Elsevier Ltd. All rights reserved.

Du, Preez, L. H.; Jansen, Van Rensburg, P. J.; Jooste, A. M.; Carr, J. A.; Giesy, J. P.; Gross, T. S.; Kendall, R. J.; Smith, E. E.; Van Der Kraak, G.; Solomon, K. R.

2005-01-01

222

Seasonal exposures to triazine and other pesticides in surface waters in the western Highveld corn-production region in South Africa.  

PubMed

The objective of this study was to characterize concentrations of atrazine, terbuthylazine, and other pesticides in amphibian habitats in surface waters of a corn-production area of the western Highveld region (North-West Province) of South Africa. The study was conducted from November 2001 to June 2002, coinciding with the corn-production season. Pesticide residues were measured at regular intervals in surface water from eight ponds, three in a non-corn-growing area (NCGA) and five within the corn-growing area (CGA). Measured atrazine concentrations differed significantly among sites and between samples. In the five CGA sites, the maximum atrazine concentrations measured during the study ranged from 1.2 to 9.3 microg/L. Although no atrazine was recorded as being applied in the catchment of the three NCGA sites, maximum concentrations from 0.39 to 0.84 microg/L were measured during the study, possibly as a result of atmospheric transport. Maximum measured concentrations of terbuthylazine ranged from 1.22 to 2.1 microg/L in the NCGA sites and from 1.04 to 4.1 microg/L in the CGA sites. The source of terbuthylazine in the NCGA sites may have been in use other than in corn. The triazine degradation products, deisopropylatrazine (DIA) and deethylatrazine (DEA) and diaminochlorotriazine (DACT) were also found in water from both the CGA and NCGA sites. Concentrations of DIA were > or = 1 microg/L throughout the season, while DEA concentrations were mostly <0.5 microg/L before planting but increased after planting and application of herbicides to concentrations >2 microg/L in some locations. Concentrations of DACT were highly variable (LOD to 8 microg/L) both before and after planting and application, suggesting that they resulted from historical use of triazines in the area. Other herbicides such as simazine and acetochlor were only detected infrequently and pesticides such as S-metolachlor, cypermethrin, monocrotophos, and terbuphos, known to be used in the CGA, were not detected in any of the samples. Because of dilution by higher than normal rainfall in the study period, these concentrations may not be predictive of those in years of normal rainfall. PMID:15701400

Du Preez, L H; Jansen van Rensburg, P J; Jooste, A M; Carr, J A; Giesy, J P; Gross, T S; Kendall, R J; Smith, E E; Van Der Kraak, G; Solomon, K R

2005-05-01

223

The role of purine degradation in methane biosynthesis and energy production in Methanococcus vannielii  

Microsoft Academic Search

Research continues on the role of purine degradation in methane biosynthesis and energy production in Methanococcus vannielii. This report summarizes current progress of the research. Topics include: A survey of other methanogens for the purine degradation pathway; isolate and characterize the enzyme and products of formiminoglycine cleavage; ascertain the fate of glycine from the formiminoglycine cleavage; elucidate the route of

DeMoll

1990-01-01

224

76 FR 41178 - Pesticides; Policies Concerning Products Containing Nanoscale Materials; Opportunity for Public...  

Federal Register 2010, 2011, 2012, 2013

...under FOR FURTHER INFORMATION CONTACT. List of Subjects Environmental protection, Administrative practice and procedure, Nanotechnology, Pesticides and pests. Dated: July 6, 2011. William R. Diamond, Acting Assistant Administrator, Office of...

2011-07-13

225

[Productions analyses and pH dynamics during rice straw degradation by the lignocellulose degradation bacteria system WSC-6].  

PubMed

To detect the metabolic characteristic of rice straw degradation by composite microbial system WSC-6, we cultured WSC-6 in the media used rice straw as the limiting carbon source. The rice straw was added in the style of different quantity once or the same quantity at the different time intervals during 90 days culture. The systems were cultivated under static condition at 50 degrees C. The degradation ratio, absolute degradation quantity,products from degradation and dynamics of pH value of fermentation system were all investigated. The results showed: when 1% rice straw was added once, the pH of fermentation system decreased from initial 7.8 to 6.0 within the first three days inoculation, and after six-day cultivation, it increased to 8.0 and was stable. For dissolved oxygen concentration (DO), the value was maintained at range of 0.01 to 0.12 mg x L(-1) of microaerobic condition. During the rice straw degradation, more than ten kinds of products including ethanol, acetic acid, lactic acid and glycerol and so on were detected using GC-MS. Especially, the highest concentration of lactic acid among all products was 7.381 g x L(-1) at 24 h after inoculation. During 90-day cultivation, for the addition treatments of the different quantity once, the more rice straw added, the quicker and lower the pH decreased, and the longer time intervals returned the pHs were. Especially for 5.0% addition, when 5.0% of rice straw was added once, pH did not increase again after it decreased. Among the addition of the same quantity at the different time intervals, the trend of decrease-increase in pH at 12-day and 15-day intervals could be repeated and high degradation activity well maintained. After 90-day of inoculation, the highest degradation ratio occurred in the treatment at 15-day interval, which was 86.7%. The highest absolute quantity occurred in the treatment at 6-day interval, which was 32.4 g. The trend of pH changes can indicate the activity of lignocellulose degradation and degradation process of the WSC-6. PMID:18441944

Wang, Wei-Dong; Wang, Xiao-Fen; Liu, Chang-Li; Li, Yu-Hua; Lü, Yu-Cai; Cui, Zong-Jun

2008-01-01

226

Distribution of chlorinated pesticides in soybeans, soybean oil, and its by-products during processing  

Microsoft Academic Search

Soybean samples were collected from seven different locales in Central Illinois and subjected to analysis for chlorinated\\u000a pesticides. Different parts of the beans showed varying levels of residue concentrations. It was found that pesticide residues\\u000a had a tendency to accumulate, in descending order, in hypocotyls, hulls and cotyledons on the basis of ground samples. When\\u000a oils extracted from the same

M. M. Chaudry; A. I. Nelson; E. G. Perkins

1978-01-01

227

PR notice 87-1. Notice to manufacturers, formulators, producers and registrants of pesticide products  

SciTech Connect

The notice describes the label improvement program for pesticides registered under Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) and applied through irrigation systems (also known as chemigation). The notice explains the program, defines who and what the notice applies to, and details about how the labeling is to be done. These label changes are necessary to prevent unnecessary human or animal exposure to the pesticide.

Not Available

1987-03-01

228

Detection of Pesticides and Pesticide Metabolites Using the Cross Reactivity of Enzyme Immunoassays  

USGS Publications Warehouse

Enzyme immunoassay is an important environmental analysis method that may be used to identify many pesticide analytes in water samples. Because of similarities in chemical structure between various members of a pesticide class, there often may be an unwanted response that is characterized by a percentage of cross reactivity. Also, there may be cross reactivity caused by degradation products of the target analyte that may be present in the sample. In this paper, the concept of cross reactivity caused by degradation products or by nontarget analytes is explored as a tool for identification of metabolites or structurally similar compounds not previously known to be present in water samples. Two examples are examined in this paper from various water quality studies. They are alachlor and its metabolite, alachlor ethane sulfonic acid, and atrazine and its class members, prometryn and propazine. A method for using cross reactivity for the detection of these compounds is explained in this paper.

Thurman, E.M.; Aga, D.S.

2001-01-01

229

The role of purine degradation in methane biosynthesis and energy production in Methanococcus vannielii  

SciTech Connect

Research continues on the role of purine degradation in methane biosynthesis and energy production in Methanococcus vannielii. This report summarizes current progress of the research. Topics include: A survey of other methanogens for the purine degradation pathway; isolate and characterize the enzyme and products of formiminoglycine cleavage; ascertain the fate of glycine from the formiminoglycine cleavage; elucidate the route of incorporation of the formyl moiety of formiminoglycine into methane biosynthesis; determine the percent methane and amino acid synthesis from purine degradation; and related studies on xanthine dehydrogenase and pyrimidine degradation of M. Vannielii. (SM)

DeMoll, E.

1990-10-22

230

Toxicity of pesticide and fertilizer mixtures simulating corn production to eggs of snapping turtles (Chelydra serpentina).  

PubMed

Many reptiles oviposit in soils associated with agricultural landscapes. We evaluated the toxicity of a pesticide and fertilizer regime similar to those used in corn production in Ontario on the survivorship of exposed snapping turtle (Chelydra serpentina) eggs. The herbicides atrazine, dimethenamid, and glyphosate, the pyrethroid insecticide tefluthrin, and the fertilizer ammonia, were applied to clean soil, both as partial mixtures within chemical classes, as well as complete mixtures. Eggs were incubated in the soil in a garden plot in which these mixtures were applied at a typical field application rate, and higher rates. Otherwise, the eggs were unmanipulated and were subject to ambient temperature and weather conditions. Eggs were also exposed at male producing temperatures in the laboratory in covered bins in the same soil, where there was less opportunity for loss through volatilization or leaching. Egg mortality was 100% at 10× the typical field application rate of the complete mixture, both with and without tefluthrin. At typical field application rates, hatching success ranged between 91.7 and 95.8%. Eggs exposed only to herbicides were not negatively affected at any application rates. Although fertilizer treatments at typical field application rates did not affect eggs, mortality was remarkably higher at three times this rate, and 100% at higher rates. The frequency of deformities of hatchlings was elevated at the highest application rate of the insecticide tefluthrin. The majority of the toxicity of the mixture was not due to the herbicides or insecticide, but was due to the ammonia fertilizer. At typical field application rates, the chemical regime associated with corn production does not appear to have any detrimental impacts upon turtle egg development; however toxicity dramatically increases if this threshold is passed. PMID:21831407

de Solla, Shane Raymond; Martin, Pamela Anne; Mikoda, Paul

2011-09-15

231

Effects of pesticides on songbird productivity in conjunction with pecan cultivation in southern Georgia: A multiple-exposure experimental design  

USGS Publications Warehouse

A prototypic experimental design was used to assess sublethal effects of multiple and varied organophosphates and carbamates on reproduction in birds. The design allowed for classification of pesticide exposure according to toxicity of applied compounds and type and frequency of applications. Daily survival rates (DSRs) of nests, eggs, and nestlings were determined for northern mockingbirds (Mimus polyglottos), brown thrashers (Toxostoma rufum), and northern cardinals (Cardinalis cardinalis) nesting along edges of pecan orchards and row crops in southern Georgia [USA]. Egg and nestling DSRs for all species combined varied inversely (P 0.05) among three exposure levels. Brain cholinesterase activities were age-dependent and substantiated adult, but not nestling, exposure. Results suggest that increasing exposure to pesticides may reduce songbird productivity.

Patnode, K.A.; White, D.H.

1991-01-01

232

Advances in pesticide environmental fate and exposure assessments.  

PubMed

Globalization of markets and the growing world population increase threats of invasive and exotic species and place greater demands on food and fiber production. Pest management in both agricultural and nonagricultural settings employs established practices and new biological, chemical, and management technologies. Pesticides are an essential tool in integrated pest management. Without pesticides a significant percentage of food and fiber crops would be lost, infectious diseases would increase, and valuable native habitats would be devastated. Therefore, it is important to understand the environmental fate of pesticides and assess their potential exposure and associated risks to human health and the environment. This paper summarizes the Advances in Pesticide Environmental Fate and Exposure Assessment symposium held at the 231st National Meeting of the American Chemical Society (Atlanta, GA, 2006). The focus of the symposium was to provide current information on advances in pesticide environmental fate and exposure assessments. Thirty papers were presented on advances ranging from subcellular processes to watershed-scale studies on topics including chemical degradation, sorption, and transport; improved methodologies; use of modeling and predictive tools; exposure assessment; and treatment and remediation. This information is necessary to develop more effective pesticide use and management practices, to better understand pesticide fate and associated exposures and risks, to develop mitigation and remediation strategies, and to establish sound science-based regulations. PMID:17552539

Rice, Pamela J; Rice, Patricia J; Arthur, Ellen L; Barefoot, Aldos C

2007-07-11

233

Factors Affecting the Occurrence and Distribution of Pesticides in the Yakima River Basin, Washington, 2000  

USGS Publications Warehouse

The Yakima River Basin is a major center of agricultural production. With a cultivated area of about 450,000 ha (hectares), the region is an important producer of tree fruit, grapes, hops, and dairy products as well as a variety of smaller production crops. To control pest insects, weeds, and fungal infections, about 146 pesticide active ingredients were applied in various formulations during the 2000 growing season. Forty-six streams or drains in the Yakima River Basin were sampled for pesticides in July and October of 2000. Water samples also were collected from 11 irrigation canals in July. The samples were analyzed for 75 of the pesticide active ingredients applied during the 2000 growing season - 63 percent of the pesticides were detected. An additional 14 pesticide degradates were detected, including widespread occurrence of 2 degradates of DDT. The most frequently detected herbicide was 2,4-D, which was used on a variety of crops and along rights-of-way. It was detected in 82 percent of the samples collected in July. The most frequently detected insecticide was azinphos-methyl, which was used primarily on tree fruit. It was detected in 37 percent of the samples collected in July. All occurrences of azinphos-methyl exceeded the Environmental Protection Agency recommended chronic concentration for the protection of aquatic organisms. More than 90 percent of the July samples and 79 percent of the October samples contained two or more pesticides, with a median of nine in July and five in October. The most frequently occurring herbicides in mixtures were atrazine, 2,4-D, and the degradate deethylatrazine. The most frequently occurring insecticides in mixtures were azinphos-methyl, carbaryl, and p,p'-DDE (a degradate of DDT). A greater number of pesticides and higher concentrations were found in July than in October, reflecting greater usage and water availability for transport during the summer growing and irrigation season. Most of the samples collected in October (baseflow conditions) contained at least one pesticide. The mass ratio of instream pesticide load and application (pesticide loss) was used to explore spatial and temporal patterns of pesticide occurrence. Losses of pesticides with large organic carbon-water partitioning coefficients (Koc) values, which adhere strongly to sediment and plant surfaces, were smallest in catchments where sprinkler and drip irrigation systems were widely used. In contrast, losses of pesticides with low Koc values did not relate well with irrigation method.

Johnson, Henry M.

2007-01-01

234

[New clean-up method with dispersive solid-phase extraction for simultaneous determination of pesticide residues in livestock products by GC-MS/MS].  

PubMed

A simple clean-up method was developed for the simultaneous determination of pesticide residues in livestock products by GC-MS/MS. The pesticide residues were extracted with acetonitrile-ethanol (1 : 1), and matrix components such as adipose were effectively eliminated by a combination of refrigerated centrifugation, dispersive solid-phase extraction, and multifunctional column chromatography. In this method, samples are treated quickly and easily without the need for gel-permeation chromatography. Among 131 pesticides tested, 115 showed recovery within the range from 70 to 120%, with relative standard deviations of less than 15%. The quantification limits for the 115 pesticides in livestock products were 0.001 to 0.01 µg/g. PMID:22688022

Kondo, Takahide; Kaburagi, Yasuo; Shibata, Masahisa; Kurokawa, Chieko; Inoue, Yutaka; Yamamoto, Yoshihiko; Miyazaki, Motonobu

2012-01-01

235

Effect of self-degradation products on crystallization of protease thermolysin  

NASA Astrophysics Data System (ADS)

The effect of self-degradation products of protease thermolysin on the crystallization of thermolysin was investigated. Crystallizations were carried out at the concentration of the self-degradation products of 0 to 0.622 mg/ml, 5 C, and pH 7.0. The initial concentration of thermolysin was constant (1.70 +/- 0.01 mg/ml). Crystallizations were monitored by dynamic light scattering and photomicroscopy. The crystallization of thermolysin in the presence of the self-degradation products proceeded through two successive steps: the formation of primary particles and the formation of large crystals by the aggregation of the primary particles. Low concentration of the self-degradation products (0.212 mg/ml) accelerated the formation of the primary particles and also the formation of the large crystals. High concentration of the self-degradation products, however, inhibited the formation of the primary particles and their aggregation to the large crystals. As the result, a large number of small aggregates which had not grown to the large crystals were observed by photomicroscopy. An analysis of the crystals and the primary particles formed in the presence of the self-degradation products by gel filtration high performance liquid chromatography revealed that the self-degradation products are not incorporated in the primary particles, but are incorporated probably in the openings between the primary particles during the crystallization.

Sazaki, Gen; Aoki, Satoshi; Ooshima, Hiroshi; Kato, Jyoji

1994-05-01

236

Biological Degradation of Common Pharmaceuticals and Personal Care Products in Soils with High Water Content  

Microsoft Academic Search

Biological degradation rates of six pharmaceuticals and personal care products were examined in soil from a land application\\u000a site and in adjacent soil with no prior history of effluent exposure. Microbial degradation rates were compared over 2 weeks\\u000a under standing water or saturated conditions and draining conditions after having been saturated for 3 days. Biological degradation\\u000a of 17?-estradiol exhibited rapid rates of

Deborah L. Carr; Audra N. Morse; John C. Zak; Todd A. Anderson

2011-01-01

237

A study of pesticide residue levels and insecticide resistance in selected aquatic organisms occurring around the Bryan-College Station agricultural production areas  

E-print Network

A STUDY OF PESTICIDE RESIDUE LEVELS AND INSECTICIDE RESISTANCE IN SELECTED AQUATIC ORGANISMS OCCURRING AROUND THE BRYAN-COLLEGE STATION AGRICULTURAL PRODUCTION AREAS A Thes1s by LARRY DAMES DZIUK Submitted to the Graduate College of Texas... ASM University 1n partial fulfillment of the requirement for the degree of MASTFR OF SCIENCE August 1971 Major ub. 'ect: Fntomology A STUDY OF PESTICIDE RESIDUE LEVELS AND INSECTICIDE RESISTANCE IN SELECTED A)UATIC ORGANISMS OCCURRING AROUND...

Dziuk, Larry James

2012-06-07

238

Evaluation of serum pesticide residue levels and liver function in persons exposed to dairy products contaminated with heptachlor  

SciTech Connect

The authors studied a group of 45 dairy farm family members who had consumed undiluted raw milk products known to be contaminated with residues of the pesticide heptachlor at concentrations as high as 89.2 ppm (fat basis). They compared results of serum pesticide assays for these exposed persons with results for an unexposed group of 94 persons from the same geographic area and the results from the Second National Health and Nutrition Examination Survey. The exposed group had significantly higher mean levels of primary heptachlor metabolites-i.e., heptachlor epoxide and oxychlordane than the unexposed group. In the exposed group, 21.2% had evaluated serum concentrations of these same metabolites; this rate was significantly greater than the rates in both the unexposed farm family members (heptachlor epoxide, 3.8%; oxychlordane, 6.3%) and the Second National Health and Nutrition Examination Survey sample (2.5% for both metabolites). However they found no evidence of related acute and/or subacute hepatic effects in these exposed persons regardless of their serum concentrations of pesticide residues.

Stehr-Green, P.A.; Wohlleb, J.C.; Royce, W.; Head, S.L.

1988-01-15

239

METHOXYCHLOR AND DDT DEGRADATION IN WATER: RATES AND PRODUCTS  

EPA Science Inventory

Methoxychlor (2,2-bis(methoxyphenyl)-1,1,1-trichloroethane) and DDT (2,2-bis(chlorophenyl)-1,1,1-trichloroethane) undergo different hydrolytic degradation pathways in water at pH's common to the aquatic environment. For methoxychlor at common aquatic pH's, the reaction is pH inde...

240

Thermochemical alkaline degradation of polysaccharide materials: Product characterization and identification  

SciTech Connect

Degradation of cellulosics or starch in alkaline solution produces mostly organic acids which are monocarboxylic in nature. Seven of the organic acids have been identified as formic, acetic, glycolic, lactic, 2-hydroxybutyric, 2-hydroxyisobutyric and 2-hydroxyvaleric acids. In total, their yields amount to 41-46% of starting material weight.

Krochta, J.M.; Hudson, J.S.; Tillin, S.J.; Spala, K.

1985-01-01

241

Herbicides and herbicide degradation products in upper midwest agricultural streams during august base-flow conditions  

USGS Publications Warehouse

Herbicide concentrations in streams of the U.S. Midwest have been shown to decrease through the growing season due to a variety of chemical and physical factors. The occurrence of herbicide degradation products at the end of the growing season is not well known. This study was conducted to document the occurrence of commonly used herbicides and their degradation products in Illinois, Iowa, and Minnesota streams during base-flow conditions in August 1997. Atrazine, the most frequently detected herbicide (94%), was present at relatively low concentrations (median 0.17 ??g L-1). Metolachlor was detected in 59% and cyanazine in 37% of the samples. Seven of nine compounds detected in more than 50% of the samples were degradation products. The total concentration of the degradation products (median of 4.4 ??g L-1) was significantly greater than the total concentration of parent compounds (median of 0.26 ??g L-1). Atrazine compounds were present less frequently and in significantly smaller concentrations in streams draining watersheds with soils developed on less permeable tills than in watersheds with soils developed on more permeable loess. The detection and concentration of triazine compounds was negatively correlated with antecedent rainfall (April-July). In contrast, acetanalide compounds were positively correlated with antecedant rainfall in late spring and early summer that may transport the acetanalide degradates into ground water and subsequently into nearby streams. The distribution of atrazine degradation products suggests regional differences in atrazine degradation processes.

Kalkhoff, S. J.; Lee, K. E.; Porter, S. D.; Terrio, P. J.; Thurman, E. M.

2003-01-01

242

Sterols heating: degradation and formation of their ring-structure polar oxidation products.  

PubMed

Cholesterol and phytosterols can be oxidised under heating conditions to give sterol oxidation products (SOPs), known by their toxic effects. This paper studied the degradation of cholesterol and three plant sterols during a 360 min heating treatment (180 °C). The formation and further degradation of SOPs was also analysed by GC-MS. Results revealed a sterol susceptibility to degradation according to the following decreasing order: campesterol??-sitosterol?stigmasterol>cholesterol. The degradation curve fit (R(2)=0.907-0.979) a logarithmic model. SOPs increased their concentration during the first 5-10 min and thereafter, their degradation rate was higher than their formation rate, resulting in a decrease over time. Irrespective of the sterol from which they had derived, 7-keto derivatives presented the highest levels throughout the entire process, and also SOPs with the same type of oxidation followed a similar degradation pattern (R=0.90-0.99). PMID:22868149

Barriuso, Blanca; Otaegui-Arrazola, Ane; Menéndez-Carreńo, María; Astiasarán, Iciar; Ansorena, Diana

2012-11-15

243

DETECTION OF MUTAGENIC PROPERTIES OF PESTICIDES USED IN COMMERCIAL CORN PRODUCTION  

EPA Science Inventory

This project encompassed the analysis of 21 pesticides and 12 combinations of herbicides for their genotoxic properties. Three genetic assays were employed: reverse mutation in Salmonella typhimurium, gene conversion in S. cerveisiae and reverse mutation in Z. mays. The use of th...

244

Glucagon degradation by a product of the Walker 256 carcinosarcoma  

SciTech Connect

Male Sprague-Dawley rats (125-150g) were implanted (im.) with the Walker 256 carcinosarcoma. After both 7 and 10 days, plasma levels of glucagon in tumor-bearing rats were approximately half the level seen in control rats (P < 0.01) even though fasting plasma glucose levels were slightly (but not significantly) less in the tumor-bearing rats. To determine if the tumor degrades the hormone, tumor cells were incubated at room temperature with /sup 125/I-glucagon (0.075 ..mu..Ci, 2200 Ci/mmol) in 20mM TRIS-HCl buffer (pH 7.4) with 2.5% bovine serum albumin (total volume of 750 ..mu..l) for 45 min. After incubation with tumor cells, only about 25% of the total radiolabel was TCA-precipitable vs 97% in the control (minus tumor cells) incubations. It also appears that the tumor cells may release a substance which degrades hormone. If tumor cells are preincubated for 60 min at 37/sup 0/ then removed from the medium, the incubation medium contains a factor which degrades subsequently added /sup 125/I-glucagon (57% TCA-precipitable vs 98% in control incubations). That this factor is a protease is suggested by the results of another experiment in which aprotinin (a protease inhibitor, 1 mg/ml), when added along with the labeled glucagon, virtually eliminated degradation by a factor released from the tumor cells (79% TCA-precipitable in the absence of aprotinin vs 94% in its presence and 98% in controls).

Zepp, E.A.

1986-03-05

245

Determination of trace amounts of chemical warfare agent degradation products in decontamination solutions with NMR spectroscopy.  

PubMed

Decontamination solutions are used for an efficient detoxification of chemical warfare agents (CWAs). As these solutions can be composed of strong alkaline chemicals with hydrolyzing and oxidizing properties, the analysis of CWA degradation products in trace levels from these solutions imposes a challenge for any analytical technique. Here, we present results of application of nuclear magnetic resonance spectroscopy for analysis of trace amounts of CWA degradation products in several untreated decontamination solutions. Degradation products of the nerve agents sarin, soman, and VX were selectively monitored with substantially reduced interference of background signals by 1D 1H-31P heteronuclear single quantum coherence (HSQC) spectrometry. The detection limit of the chemicals was at the low part-per-million level (2-10 microg/mL) in all studied solutions. In addition, the concentration of the degradation products was obtained with sufficient confidence with external standards. PMID:17973498

Koskela, Harri; Rapinoja, Marja-Leena; Kuitunen, Marja-Leena; Vanninen, Paula

2007-12-01

246

21 CFR 864.7320 - Fibrinogen/fibrin degradation products assay.  

Code of Federal Regulations, 2011 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7320 Fibrinogen/fibrin degradation products assay. (a)...

2011-04-01

247

21 CFR 864.7320 - Fibrinogen/fibrin degradation products assay.  

Code of Federal Regulations, 2012 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7320 Fibrinogen/fibrin degradation products assay. (a)...

2012-04-01

248

21 CFR 864.7320 - Fibrinogen/fibrin degradation products assay.  

Code of Federal Regulations, 2010 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7320 Fibrinogen/fibrin degradation products assay. (a)...

2010-04-01

249

21 CFR 864.7320 - Fibrinogen/fibrin degradation products assay.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7320 Fibrinogen/fibrin degradation products assay. (a)...

2013-04-01

250

The distribution of phytoplankton pigments and their degradation products in the Southern Ocean  

E-print Network

THE DISTRIBUTION OF PHYTOPLANKTON PIGMENTS AND THEIR DEGRADATION PRODUCTS IN THE SOUTHERN OCEAN A Thesis by TAMARA JEAN FRANK Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1987 Ma]or Sub]ect: Oceanography THE DISTRIBUTION OP PHYTOPLANKTON PIGMENTS AND THEIR DEGRADATION PRODUCTS IN THE SOUTHERN OCEAN A Thesis by Approved as to style and content by: James M. Brooks Chairman of Committee...

Frank, Tamara Jean

2012-06-07

251

Toxicity and physical properties of atrazine and its degradation products: A literature survey  

SciTech Connect

The Tennessee Valley Authority`s Environmental Research Center has been developing a means of detoxifying atrazine waste waters using TiO{sub 2} photocatalysis. The toxicity and physical properties of atrazine and its degradation products will probably be required information in obtaining permits from the United States Environmental Protection Agency for the demonstration of any photocatalytic treatment of atrazine waste waters. The following report is a literature survey of the toxicological and physical properties of atrazine and its degradation products.

Pugh, K.C.

1994-10-01

252

Effects of the herbicide atrazine and its degradation products, alone and in combination, on phototrophic microorganisms  

Microsoft Academic Search

Toxic effects of the herbicide atrazine and four of its degradation products were determined for growth, photosynthesis, and acetylene-reducing ability of two species of green algae and three species of cyanobacteria. Atrazine was significantly more toxic than its degradation products towards the above test criteria, yielding EC50 values ranging from 0.1 to 0.5 ppm (µg\\/ml) for photosynthesis and 0.03 to

Glenn W. Stratton

1984-01-01

253

Comparative Aquatic Toxicity Evaluation of 2-(Thiocyanomethylthio)benzothiazole and Selected Degradation Products Using Ceriodaphnia dubia  

Microsoft Academic Search

2-(Thiocyanomethylthio)benzothiazole (TCMTB) is a biocide used in the leather, pulp and paper, and water-treatment industries. TCMTB may enter aquatic ecosystems during its manufacture and use. TCMTB is environmentally unstable; therefore, it is important to evaluate the toxicity of the more persistent degradation products. This study compared the toxicity of TCMTB with its degradation products 2-mercaptobenzothiazole (2-MBT), 2-(methylthio)benzothiazole (MTBT), benzothiazole (BT),

S. T. Nawrocki; K. D. Drake; C. F. Watson; G. D. Foster; K. J. Maier

2005-01-01

254

Chemical stability of chlortetracycline and chlortetracycline degradation products and epimers in soil interstitial water  

Microsoft Academic Search

Tetracyclines and tetracycline degradation products and epimers end up in the environment. In order to predict the persistence of the potential dominating species of the chlortetracyclines in the environment, the chemical stability of chlortetracycline (CTC) and four major CTC degradation products and epimers (iso-CTC, 4-epi-CTC, anhydro-CTC, and 4-epi-anhydro-CTC) was studied in milliQ water and soil interstitial water (SIW) under environmentally

Tue Sřeborg; Flemming Ingerslev; Bent Halling-Sřrensen

2004-01-01

255

Inhibitory action of potassium sorbate degradation products against Staphylococcus aureus growth in laboratory media.  

PubMed

The inhibitory action of potassium sorbate (KS) degradation products against Staphylococcus aureus growth was examined in model aqueous systems. KS degradation products formation was induced by the storage at 70 degrees C for 7 days or at 37 degrees C for 90 days of aqueous systems containing basically brain heart infusion, yeast extract and different amounts of KS at pH 5.5. After storage, residual amounts of KS were measured and each system was inoculated with a pool of three S. aureus strains at 10(4) colony forming units/ml. Degradation products from KS generally inhibited S. aureus growth by two to three log cycles. However, the population of S. aureus reached a higher level when the degradation products were formed at 37 degrees C suggesting that the nature of the degradation products seemed to depend on the temperature at which they were produced. The inhibitory activity produced by KS degradation products along with residual amounts of KS was smaller than the one produced by the initial amounts of the preservative. PMID:10746581

Campos, C A; Alzamora, S M; Gerschenson, L N

2000-03-10

256

Modeling potential freshwater ecotoxicity impacts due to pesticide use in biofuel feedstock production: the cases of maize, rapeseed, salix, soybean, sugar cane, and wheat.  

PubMed

The inclusion of ecotoxicity impacts of pesticides in environmental assessments of biobased products has long been hampered by methodological challenges. We expanded the pesticide database and the regional coverage of the pesticide emission model PestLCI v.2.0, combined it with the impact assessment model USEtox, and assessed potential freshwater ecotoxicity impacts (PFEIs) of pesticide use in selected biofuel feedstock production cases, namely: maize (Iowa, US, two cases), rapeseed (Schleswig-Holstein, Germany), Salix (South Central Sweden), soybean (Mato Grosso, Brazil, two cases), sugar cane (Săo Paulo, Brazil), and wheat (Schleswig-Holstein, Germany). We found that PFEIs caused by pesticide use in feedstock production varied greatly, up to 3 orders of magnitude. Salix has the lowest PFEI per unit of energy output and per unit of cultivated area. Impacts per biofuel unit were 30, 750, and 1000 times greater, respectively, for the sugar cane, wheat and rapeseed cases than for Salix. For maize genetically engineered (GE) to resist glyphosate herbicides and to produce its own insecticidal toxin, maize GE to resist glyphosate, soybeans GE to resist glyphosate and conventional soybeans, the impacts were 110, 270, 305, and 310 times greater than for Salix, respectively. The significance of field and site-specific conditions are discussed, as well as options for reducing negative impacts in biofuel feedstock production. PMID:25207789

Nordborg, Maria; Cederberg, Christel; Berndes, Göran

2014-10-01

257

40 CFR 152.175 - Pesticides classified for restricted use.  

Code of Federal Regulations, 2012 CFR

...Classification of Pesticides § 152.175 Pesticides classified for restricted use. The following uses of pesticide products containing the active ingredients...Residue effects on avian species. Hazard to bees. All dust and granular...

2012-07-01

258

[Surface-enhanced Raman spectra analysis of trace degradation products from goat horn].  

PubMed

Nano-silver colloid was synthesized by using microwave method on the mixtures of sodium citrate solution and silver nitrate solution. The method has advantages of fast heating speed, uniform temperature distribution and easily controlled reaction conditions. The sizes and size distributions of the silver particles were characterized by means of quasi-elastic laser scattering (QLS). The average particles size was (53.27 +/- 2.65) nm and the size of the particles was mainly distributed around 56 nm. Surface-enhanced Raman spectra of the degradation products from goat horn were obtained with silver colloid as active substrate. It was observed that the Raman signal of SERS was enhanced significantly compared with that of regular Raman spectrum, especially at the Raman bands of 659, 830, 850, 929, 999, 1 028, 1 280, 1 439 and 1 599 cm(-1) which reflect the biochemical components in degradation products. The characteristic Raman bands of degradation products from goat horn were preliminary assigned. The assignments showed that the main constituents of the degradation products from goat horn were amino acids and polypeptides. It was for the first time that Surface-enhanced Raman spectroscopy was used to detect trace degradation products from the horns. Raman signal enhancement can be obtained with high sensitivity for the trace concentrations as low as ppm level. It is concluded that surface-enhanced Raman spectroscopy can provide a fast, direct and precise detecting method for the detection of trace degradation solution from horns. PMID:25007614

Pan, Yan-Ting; Ao, Ning-Jian; Shan, Guang-Hua; Zhang, Gang-Ping; Zhang, Quan-Bin; Yang, Ji-Wang; He, Chun-Lan; Huang, Yao-Xiong

2014-04-01

259

Identification of degradation products of erythromycin A arising from ozone and advanced oxidation process treatment.  

PubMed

The degradation products of the macrolide antibiotic erythromycin A (ERY) arising from direct ozone attack and hydroxyl radical attack are presented for the first time. Ozone treatment was carried out by spiking ozone stock solutions to solutions containing ERY-ERY:O3 = 1:5 and 1:10 (M:M), while, in parallel, t-BuOH was used as a hydroxyl radical (*OH) scavenger. The advanced oxidation processes (AOPs) O3/UV, O3/H2O2, and UV/H2O2 were carried out to recognize and verify possible differences between their primary degradation products; the initial concentrations were ERY:O3 = 1:5 (M:M), ERY:O3:H202 = 1:5:5 (M:M:M), or ERY:H202 = 1:5 (M:M), respectively. Six degradation products were identified from ozonation-one originates from direct ozone attack on the tertiary amine group, while the others arise from radical ion attack, which might be formed during degradation of O3 in water. Fewer primary degradation products were observed arising from *OH-based treatments (AOP) than from ozonation, possibly because the reaction of *OH radicals is non-selective and typically is diffusion-controlled. Four degradation products were detected by *OH radical attacks; two of them already were observed during ozonation, with one as an oxidized ERY molecule and the other as a non-oxidized fragment of the ERY molecule. PMID:20942335

Luiz, Danielle B; Genena, Aziza K; Virmond, Elaine; José, Humberto J; Moreira, Regina F P M; Gebhardt, Wilhelm; Schröder, Horst Fr

2010-01-01

260

Comparative aquatic toxicity evaluation of 2-(thiocyanomethylthio)benzothiazole and selected degradation products using Ceriodaphnia dubia.  

PubMed

2-(Thiocyanomethylthio)benzothiazole (TCMTB) is a biocide used in the leather, pulp and paper, and water-treatment industries. TCMTB may enter aquatic ecosystems during its manufacture and use. TCMTB is environmentally unstable; therefore, it is important to evaluate the toxicity of the more persistent degradation products. This study compared the toxicity of TCMTB with its degradation products 2-mercaptobenzothiazole (2-MBT), 2-(methylthio)benzothiazole (MTBT), benzothiazole (BT), and 2-hydroxybenzothiazole (HOBT). Toxicity was determined using Ceriodaphnia dubia 48-hour acute and 7-day chronic test protocols. TCMTB was the most toxic compound evaluated in both the acute and chronic tests with EC50s of 15.3 and 9.64 microg/L, respectively. 2-MBT, the first degradation product, was the second most toxic compound with acute and chronic EC50s of 4.19 and 1.25 mg/L, respectively. The toxicity of MTBT and HOBT were similar with acute EC50s of 12.7 and 15.1 mg/L and chronic EC50s of 6.36 and 8.31 mg/L, respectively. The least toxic compound was BT with acute and chronic EC50s of 24.6 and 54.9 mg/L, respectively. TCMTB was orders of magnitude more toxic than its degradation products. Toxicity data on these benzothiazole degradation products is important because of concerns regarding their release, degradation, persistence, and non-target organism effects in aquatic ecosystems. PMID:15750776

Nawrocki, S T; Drake, K D; Watson, C F; Foster, G D; Maier, K J

2005-04-01

261

Pesticide application practices, pest knowledge, and cost-benefits of plantain production in the Bribri-Cabécar Indigenous Territories, Costa Rica  

Microsoft Academic Search

The use of pesticides in the cultivation of cash crops such as banana and plantain is increasing, in Costa Rica and worldwide. Agrochemical use and occupational and environmental exposures in export banana production have been documented in some parts of Central America. However, the extent of agrochemical use, agricultural pest knowledge, and economic components in plantain production are largely unknown

Beth A. Polidoro; Ruth M. Dahlquist; Luisa E. Castillo; Matthew J. Morra; Eduardo Somarriba; Nilsa A. Bosque-Pérez

2008-01-01

262

Fate and transport of pesticides in the ground water systems of southwest Georgia, 1993-2005.  

PubMed

Modern agricultural practices in the United States have resulted in nearly unrivaled efficiency and productivity. Unfortunately, there is also the potential for release of these compounds to the environment and consequent adverse affects on wildlife and human populations. Since 1993, the National Water-Quality Assessment (NAWQA) program of the U.S. Geological Survey has evaluated water quality in agricultural areas to address these concerns. The objective of this study is to evaluate trends in pesticide concentrations from 1993-2005 in the surficial and Upper Floridan aquifers of southwest Georgia using pesticide and pesticide degradate data collected for the NAWQA program. There were six compounds-five herbicides and one degradate-that were detected in more than 20% of samples: atrazine, deethylatrazine (DEA), metolachlor, alachlor, floumeturon, and tebuthiuron. Of the 128 wells sampled during the study, only eight wells had pesticide concentrations that either increased (7) or decreased (1) on a decadal time scale. Most of the significant trends were increasing concentrations of pesticides in older water; median pesticide concentrations did not differ between the surficial and Upper Floridan aquifers from 1993 and 2005. Deethylatrazine, in the Upper Floridan aquifer, was the only compound that had a significant change (increase) in concentration during the study. The limited number of wells with increases in pesticide concentrations suggest that ground-water sources of these compounds are not increasing in concentration over the time scale represented in this study. PMID:18765772

Dalton, Melinda S; Frick, Elizabeth A

2008-01-01

263

Activity of Meadowfoam (Limnanthes alba) Seed Meal Glucolimnanthin Degradation Products against Soil-Borne Pathogens  

PubMed Central

Meadowfoam (Limnanthes alba L.) is a herbaceous winter-spring annual grown as a commercial oil seed crop. The meal remaining after oil extraction from the seed contains up to 4% of the glucosinolate, glucolimnanthin. Degradation of glucolimnanthin yields toxic breakdown products and therefore the meal may have potential in the management of soil-borne pathogens. To maximize the pest suppressive potential of meadowfoam seed meal, it would be beneficial to know the toxicity of individual glucolimnanthin degradation products against specific soil-borne pathogens. Meloidogyne hapla second-stage juveniles (J2) and Pythium irregulare and Verticillium dahliae mycelial cultures were exposed to glucolimnanthin as well as its degradation products. Glucolimnanthin and its degradation product, 2-(3-methoxyphenyl)acetamide, were not toxic to any of the soil-borne pathogens at concentrations up to 1.0 mg/mL. Two other degradation products, 2-(3-methoxymethyl)ethanethioamide and 3-methoxyphenylacetonitrile, were toxic to M. hapla and P. irregulare but not V. dahliae. The predominant enzyme degradation product, 3-methoxybenzyl isothiocyanate was the most toxic compound against all of the soil-borne pathogens with M. hapla being the most sensitive with EC50 values (0.0025 ± 0.0001 to 0.0027 ± 0.0001 mg/mL) 20 to 40 times lower than estimated EC50 mortality values generated for P. irregulare and V. dahliae (0.05 and 0.1 mg/mL, respectively). The potential exists to manipulate meadowfoam seed meal to promote the production of specific degradation products. The conversion of glucolimnanthin into its corresponding isothiocyanate should optimize the biopesticidal properties of meadowfoam seed meal against M. hapla, P. irregulare, and V. dahliae. PMID:22142246

ZASADA, INGA A; WEILAND, JERRY E; REED, RALPH L; STEVENS, JAN F

2014-01-01

264

Identification by CI-mass spectrometry of an unexpected benzodiazepine degradation product  

NASA Astrophysics Data System (ADS)

The French Military Health Service (SSA) has developed an innovative drug product, as a treatment against neurotoxic organophosphate poisoning (NOP). It contains three drug substances: an anticholinergic, an anticonvulsant and a cholinesterase reactivator. Testing stability study, in normal conditions, over 18 months, for this speciality, has given unexpected results. Indeed, one of the drug substances, avizafone (pro-drug of diazepam), breaks down partially into a compound which migrates into the plastic container where this degradation product is demethylated after absorption. Mass spectrometry with negative chemical ionisation (negative CI-MS) was used, to monitor decomposition of the drug substance. This method first showed migration of the degradation product and has been used to monitor its evolution during the stability testing study. The demethylation seems to be due to an additive product present in the plastic. The degradation products remain trapped in the container holding the pharmaceutical formulation.

Buret, D.; Breton, D.; Clair, P.; Lafosse, M.

2006-01-01

265

Gas chromatographic-mass spectrometric separation and identification of combustion products of organo-phosphorus and chlorine pesticides and evaluation of their impact on the environment.  

PubMed

A simple and rapid GC-MS method for separation, identification and quantitative determination of combustion products of organophosphorus and chlorine pesticides viz; monocrotophos, chloropyriphos, butachlor and benzenehexachloride has been developed. The method provides a positive means of identifying organic combustion products and enables to assess not only their toxicity to human beings but also their impact on the environment. The data is useful for emergency preparations in case of fire in chemical plants and warehouses that store pesticides in large quantities. PMID:12058907

Rao, R Nageswara; Khalid, Sara; Rajani, T; Husain, S

2002-04-19

266

Removal of pesticide mixtures in a stormwater wetland collecting runoff from a vineyard catchment.  

PubMed

Wetlands can collect contaminated runoff from agricultural catchments and retain dissolved and particle-laden pesticides. However, knowledge about the capacity and functioning of wetland systems with respect to the removal of pesticides is very limited. Here we show that stormwater wetlands can efficiently remove pesticides in runoff from vineyard catchments during the period of pesticide application, although flow and hydrochemical conditions of the wetland largely vary over time. During the entire agricultural season, the inflowing load of nine fungicides, six herbicides, one insecticide and four degradation products was 8.039g whereas the outflowing load was 2.181g. Removal rates of dissolved loads by the wetland ranged from 39% (simazine) to 100% (cymoxanil, gluphosinate, kresoxim methyl and terbuthylazine). Dimethomorph, diuron, glyphosate, metalaxyl and tetraconazole were more efficiently removed in spring than in summer. More than 88% of the input mass of suspended solids was retained, underscoring the capability of the wetland to trap pesticide-laden particles via sedimentation. Only the insecticide flufenoxuron was frequently detected in the wetland sediments. Our results demonstrate that stormwater wetlands can efficiently remove pesticide mixtures in agricultural runoff during critical periods of pesticide application, although fluctuations in the runoff regime and hydrochemical characteristics can affect the removal rates of individual pesticides. PMID:21353289

Maillard, Elodie; Payraudeau, Sylvain; Faivre, Etienne; Grégoire, Caroline; Gangloff, Sophie; Imfeld, Gwenaël

2011-05-01

267

Microbial petroleum degradation enhancement by oil spill bioremediation products  

E-print Network

Biodegradation of an artificially weathered crude oil (Alaska North Slope) was compared using 13 different oil spill bioremediation agents. All products were evaluated under identical conditions emulating a marine environment. The research...

Lee, Salvador Aldrett

2012-06-07

268

Degradation of selected pharmaceutical and personal care products (PPCPs) by white-rot fungi  

Microsoft Academic Search

Today, more than 3,000 pharmaceutical and personal care products (PPCPs) are used and released into the environment at low\\u000a doses but they are barely degraded in wastewater treatment plants. One of the potential alternatives to effectively degrade\\u000a PPCPs is based on the use of white-rot fungi (WRF) and involves the oxidative action of extracellular fungal enzymes. The\\u000a aim of this

A. I. Rodarte-Morales; G. Feijoo; M. T. Moreira; J. M. Lema

269

Emulsifying Agent Production During PAHs Degradation by the White Rot Fungus Pleurotus Ostreatus D1  

Microsoft Academic Search

For the first time the production of an emulsifying agent during phthalic, 2,2?-diphenic and ?-hydroxy-?-naphthoic acids,\\u000a phenanthrene, anthracene, fluorene, pyrene, fluoranthene, and chrysene degradation by white rot fungus Pleurotus ostreatus was found. The emulsifying activity of the cultivation medium after degradation of these compounds was assessed. Maximal\\u000a activities were found in the presence of chrysene (48.4%) and ?-hydroxy-?-naphthoic acid (52.2%).

Svetlana V. Nikiforova; Natalia N. Pozdnyakova; Olga V. Turkovskaya

2009-01-01

270

Application of degradation test data to advertisement of consumer electronic products  

Microsoft Academic Search

Two kinds of reliability tests (accelerated life test and degradation test) are often performed in the process of developing a new electronic product in order to guarantee its improved performance over the lifetime. As a result of such tests, several reliability indices (parameters) can be estimated. Advertisers of a new product can utilise one of these indices as a benchmarking

So Young Sohn

2000-01-01

271

Using Oils As Pesticides  

E-print Network

* Assistant Professor and Extension Entomologist and Extension Program Specialist, The Texas A&M University System; and grad- uate student, Department of Entomology Texas A&M University. Oils have been used as pesticides for centuries and are some... of the most effective, safe alternatives to synthetic insecticides and fungicides. Most oil- based products sold as pesticides are regulated by the Environmental Protection Agency (EPA) under the Federal Insecticide, Fungicide and Rodenticide Act...

Bogran, Carlos E.; Ludwig, Scott; Metz, Bradley

2006-10-30

272

Degradation products of cyanidin glycosides from tart cherries and their bioactivities.  

PubMed

The bioactive anthocyanins present in tart cherries, Prunus cerasus L. (Rosaceae) cv. Balaton, are cyanidin 3-glucosylrutinoside (1), cyanidin 3-rutinoside (2), and cyanidin 3-glucoside (3). Cyanidin (4) is the major anthocyanidin in tart cherries. In our continued evaluation of the in vivo and in vitro efficacy of these anthocyanins to prevent inflammation and colon cancer, we have added these compounds to McCoy's 5A medium in an effort to identify their degradation products during in vitro cell culture studies. This resulted in the isolation and characterization of protocatechuic acid (5), the predominant degradation product. In addition, 2,4-dihydroxybenzoic acid (6) and 2,4,6-trihydroxybenzoic acid (7) were identified as degradation products. However, these degradation products were not quantified. Compounds 5-7 were also identified as degradation products when anthocyanins were subjected to varying pH and thermal conditions. In cyclooxygenase (COX)-I and -II enzyme inhibitory assays, compounds 5-7 did not show significant activities when compared to the NSAIDs Naproxen, Celebrex, and Vioxx, or Ibuprofen, at 50 microM concentrations. However, at a test concentration of 50 microM, the antioxidant activity of protocatechuic acid (5) was comparable to those of the commercial antioxidants tert-butylhydroquinone (TBHQ), butylated hydroxytoluene (BHT), and butylated hydroxyanisole (BHA), and superior to that of vitamin E at 10 microM concentrations. PMID:11600045

Seeram, N P; Bourquin, L D; Nair, M G

2001-10-01

273

Weed Control Methods This information is not a substitute for pesticide labeling. Always read the product label before applying any pesticide. Always check NYS registration  

E-print Network

Weed Control Methods This information is not a substitute for pesticide labeling. Always read. It is a resource to compare weed control methods and herbicide label information. Thermal Mechanical Barrier effective on newly emerged annuals Small weeds Few, large weeds Long- term control Best on young annuals Air

Keinan, Alon

274

Degradation of a stilbene-type fluorescent whitening agent with hypochlorite: identification of the degradation products by capillary electrophoresis.  

PubMed

The E,E-(4,4'-bis[2-sulfostyryl]biphenyl) (DSBP) is a fluorescent whitening agent widely used by the textile and detergent industries to whiten fabrics. Hypochlorite used to bleach fabrics oxidizes DSBP slowly at room temperature and in a higher rate at 60 degrees C. The ions of metals such as Fe, Cu, and Mn accelerate the process considerably. At ambient temperature, the oxidation results from cleavage of the stilbene bonds and involves the formation of various intermediates that evolve to end products. The intermediates form within minutes to hours and the end products within months. At 60 degrees C or in presence of the previously mentioned transition metals, intermediates form within minutes and the end products within days. The end products of the oxidation are 4-sulfobenzaldehyde and 4,4'-bisaldehyde biphenyl; in the presence of excess of hypochlorite, however, the process yields their corresponding oxidized derivatives 4-sulfobenzoic acid and 4,4'-biphenyldicarboxylic acid. Despite the chlorinating ability of hypochlorite, the major degradation products formed contain no chlorine. PMID:11596750

Blanco, M; Jiménez, L; Valverde, I

2001-10-01

275

Development of phage immuno-loop-mediated isothermal amplification assays for organophosphorus pesticides in agro-products.  

PubMed

Two immuno-loop-mediated isothermal amplification assays (iLAMP) were developed by using a phage-borne peptide that was isolated from a cyclic eight-peptide phage library. One assay was used to screen eight organophosphorus (OP) pesticides with limits of detection (LOD) between 2 and 128 ng mL(-1). The iLAMP consisted of the competitive immuno-reaction coupled to the LAMP reaction for detection. This method provides positive results in the visual color of violet, while a negative response results in a sky blue color; therefore, the iLAMP allows one to rapidly detect analytes in yes or no fashion. We validated the iLAMP by detecting parathion-methyl, parathion, and fenitrothion in Chinese cabbage, apple, and greengrocery, and the detection results were consistent with the enzyme-linked immunosorbent assay (ELISA). In conclusion, the iLAMP is a simple, rapid, sensitive, and economical method for detecting OP pesticide residues in agro-products with no instrumental requirement. PMID:25135320

Hua, Xiude; Yin, Wei; Shi, Haiyan; Li, Ming; Wang, Yanru; Wang, Hong; Ye, Yonghao; Kim, Hee Joo; Gee, Shirley J; Wang, Minghua; Liu, Fengquan; Hammock, Bruce D

2014-08-19

276

ATMOSPHERIC REACTION PRODUCTS FROM HAZARDOUS AIR POLLUTANT DEGRADATION  

EPA Science Inventory

This research project was undertaken to investigate the products of selected hazardous air pollutants (HAPs) as they react in the atmosphere. Many hazardous or potentially hazardous organic compounds are emitted into the atmosphere and are subject to chemical change by photolysis...

277

Pesticide use and application: an Indian scenario.  

PubMed

Agricultural development continues to remain the most important objective of Indian planning and policy. In the process of development of agriculture, pesticides have become an important tool as a plant protection agent for boosting food production. Further, pesticides play a significant role by keeping many dreadful diseases. However, exposure to pesticides both occupationally and environmentally causes a range of human health problems. It has been observed that the pesticides exposures are increasingly linked to immune suppression, hormone disruption, diminished intelligence, reproductive abnormalities and cancer. Currently, India is the largest producer of pesticides in Asia and ranks twelfth in the world for the use of pesticides. A vast majority of the population in India is engaged in agriculture and is therefore exposed to the pesticides used in agriculture. Although Indian average consumption of pesticide is far lower than many other developed economies, the problem of pesticide residue is very high in India. Pesticide residue in several crops has also affected the export of agricultural commodities in the last few years. In this context, pesticide safety, regulation of pesticide use, proper application technologies, and integrated pest management are some of the key strategies for minimizing human exposure to pesticides. There is a dearth of studies related to these issues in India. Therefore, the thrust of this paper was to review the technology of application of pesticides in India and recommend future strategies for the rational use of pesticides and minimizing the problems related to health and environment. PMID:19081675

Abhilash, P C; Singh, Nandita

2009-06-15

278

Extraction of acidic degradation products of organophosphorus chemical warfare agents  

Microsoft Academic Search

The analysis of alkyl alkylphosphonic acids (AAPAs) and alkylphosphonic acids (APAs), the hydrolyzed products of nerve agents, constitutes an important aspect for verifying the compliance to the Chemical weapons convention (CWC). This work devotes on the development of solid-phase extraction method using polymeric mixed-mode strong anion-exchange (Oasis MAX) cartridges for extraction of AAPAs and APAs from water. The extracted analytes

Pankaj K. Kanaujia; Deepak Pardasani; A. K. Gupta; Rajesh Kumar; R. K. Srivastava; D. K. Dubey

2007-01-01

279

Photocatalytic degradation of molinate in aqueous solutions.  

PubMed

In this study, the degradation of molinate through heterogeneous photocatalysis, using two different types of the semiconductor TiO2 as photocatalyst, as well as through homogeneous treatment, applying the photo-Fenton reaction, has been investigated. As far as heterogeneous photocatalysis is concerned, the degradation of the pesticide follows apparent first-order kinetics, while the type of the catalyst and the pH value of the solution affect the degradation rate. The effect of the addition of electron scavengers (H2O2 and K2S2O8) was also studied. In the case of photo-Fenton-assisted system, the degradation also follows pseudo-first-order kinetics. Parameters such as iron's and electron scavenger's concentration and inorganic ions strongly affect the degradation rate. The extent of pesticide mineralization was investigated using dissolved organic carbon (DOC) measurements. The toxicity of the treated solution was evaluated using the Microtox test based on the luminescent bacteria Vibrio fischeri. The detoxification and mineralization efficiency was found to be dependent on the system studied, and although it did not follow the rate of pesticide disappearance, it took place in considerable extent. The study of the photodegradation treatment was completed by the determination of the intermediate by-products formed during the process, which was carried out using LC-MS/MS technique and led to similar compounds with both processes. PMID:24928378

Bizani, E; Lambropoulou, D; Fytianos, K; Poulios, I

2014-11-01

280

Pesticides in ground water beneath Loukkos perimeter, Northwest Morocco  

NASA Astrophysics Data System (ADS)

SummaryThis study assesses pesticide occurrence in the ground water beneath the Loukkos area (Northwest Morocco). The inhabitants and farmers depend on ground water supplies for drinking water, crop irrigation and other uses. The plain provides ideal conditions for agriculture and thus the use of pesticides was increasing during the past decade. The 23 investigated pesticides belong to the endosulfan isomers and their degradation products, the triazines and the phenyl-ureas. The analyses were done using chromatographic techniques and solid-phase extraction. The analytical determination was optimized by selecting the best clean-up procedure to reach the highest pesticide recovery rate. So, clean-up with Florisil was applied for endosulfan and its metabolites. For the triazines and phenyl-ureas clean-up with LiChrolut EN was used. Endosulfan isomers and their degradation products both were detected in ground water samples of which the latter presents the highest concentrations. No herbicides (triazines and phenyl-ureas) were detected, what can be explained by the low use of these compounds in the area. With the exception of endosulfan ether, the results did not exceed the current drinking water quality established by the European Union.

El Bakouri, Hicham; Ouassini, Abdelhamid; Morillo, José; Usero, José

2008-01-01

281

Time-dependent integrity during storage of natural surface water samples for the trace analysis of pharmaceutical products, feminizing hormones and pesticides  

Microsoft Academic Search

Monitoring and analysis of trace contaminants such as pharmaceuticals and pesticides require the preservation of the samples before they can be quantified using the appropriate analytical methods. Our objective is to determine the sample shelf life to insure proper quantification of ultratrace contaminants. To this end, we tested the stability of a variety of pharmaceutical products including caffeine, natural steroids,

Khadija Aboulfadl; Cyril De Potter; Michčle Prévost; Sébastien Sauvé

2010-01-01

282

Polycyclic aromatic hydrocarbons degrading microflora in a tropical oil-production well.  

PubMed

The surrounding environment near Dagang oil-production well suffers polycyclic aromatic hydrocarbons (PAHs) pollution. In the present study, indigenous microorganisms capable of degrading PAHs were isolated and the efficiency of PAHs removal was investigated. Seven PAH-degrading strains were isolated with the ability to grow on naphthalene, phenanthrene, pyrene and fluorene. They belonged to the genus Pseudomonas, Bacillus and Rhodococcus. The strain having the highest degrading capacity for each PAH was selected by the screening test. The removal efficiency of PAHs was found to be in the order of naphthalene > fluorene > phenanthrene > pyrene. The kinetics of PAHs degradation was then followed by liquid chromatography determination and the results showed it conforms to a first-order reaction kinetic model. This study would be highly important for investigating the ability of microorganisms to utilize PAHs as growth substrates. PMID:25216932

Yu, Chan; Yao, Jun; Cai, Minmin; Yuan, Haiyan; Chen, Huilun; Ceccanti, Brunello

2014-11-01

283

Determination of pesticides associated with suspended sediments in the San Joaquin River, California, USA, using gas chromatography-ion trap mass spectrometry  

USGS Publications Warehouse

An analytical method useful for the quantification of a range of pesticides and pesticide degradation products associated with suspended sediments was developed by testing a variety of extraction and cleanup schemes. The final extraction and cleanup methods chosen for use are suitable for the quantification of the listed pesticides using gas chromatography-ion trap mass spectrometry and the removal of interfering coextractable organic material found in suspended sediments. Methylene chloride extraction followed by Florisil cleanup proved most effective for separation of coextractives from the pesticide analytes. Removal of elemental sulfur was accomplished with tetrabutylammonium hydrogen sulfite. The suitability of the method for the analysis of a variety of pesticides was evaluated, and the method detection limits (MDLs) were determined (0.1-6.0 ng/g dry weight of sediment) for 21 compounds. Recovery of pesticides dried onto natural sediments averaged 63%. Analysis of duplicate San Joaquin River suspended-sediment samples demonstrated the utility of the method for environmental samples with variability between replicate analyses lower than between environmental samples. Eight of 21 pesticides measured were observed at concentrations ranging from the MDL to more than 80 ng/g dry weight of sediment and exhibited significant temporal variability. Sediment-associated pesticides, therefore, may contribute to the transport of pesticides through aquatic systems and should be studied separately from dissolved pesticides.

Bergamaschi, B. A.; Baston, D. S.; Crepeau, K. L.; Kuivila, K. M.

1999-01-01

284

The effects of grassland degradation on plant diversity, primary productivity, and soil fertility in the alpine region of Asia's headwaters.  

PubMed

A 3-year survey was conducted to explore the relationships among plant composition, productivity, and soil fertility characterizing four different degradation stages of an alpine meadow in the source region of the Yangtze and Yellow Rivers, China. Results showed that plant species diversity, productivity, and soil fertility of the top 30-cm soil layer significantly declined with degradation stages of alpine meadow over the study period. The productivity of forbs significantly increased with degradation stages, and the soil potassium stock was not affected by grassland degradation. The vegetation composition gradually shifted from perennial graminoids (grasses and sedges) to annual forbs along the degradation gradient. The abrupt change of response in plant diversity, plant productivity, and soil nutrients was demonstrated after heavy grassland degradation. Moreover, degradation can indicate plant species diversity and productivity through changing soil fertility. However, the clear relationships are difficult to establish. In conclusion, degradation influenced ecosystem function and services, such as plant species diversity, productivity, and soil carbon and nitrogen stocks. Additionally, both plant species diversity and soil nutrients were important predictors in different degradation stages of alpine meadows. To this end, heavy degradation grade was shown to cause shift of plant community in alpine meadow, which provided an important basis for sustaining ecosystem function, manipulating the vegetation composition of the area and restoring the degraded alpine grassland. PMID:25023744

Wang, Xuexia; Dong, Shikui; Yang, Bing; Li, Yuanyuan; Su, Xukun

2014-10-01

285

Identification, characterization and cytotoxicity in vitro assay of nitazoxanide major degradation product.  

PubMed

Stress studies of the broad-spectrum antiparasitic nitazoxanide were conducted in order to isolate and elucidate the major degradation product involved in thermal, acid, alkaline, oxidative and photolytic decomposition of the drug in solution and solid state. The major degradation product was identified and characterized using techniques namely LC-DAD, (1)H NMR, (13)C NMR, IR, and MS/MS. The stability of nitazoxanide raw material and nitazoxanide in tablets and in suspension powder was studied under different conditions and the results suggest the formation of the same deacetylated degradation product occur in all cases. This product was also studied in order to determine the preliminary cytotoxicity in vitro with mononuclear cells. Compared with nitazoxanide, the degradation product showed a higher cytotoxicity at a concentration of 40 ?g mL(-1) after 48 h of incubation, under tested conditions. Therefore, stress studies showed that special care must be taken during the preparation, manufacture, and storage of this pharmaceutical drug. PMID:22483900

Malesuik, Marcelo Donadel; Gonçalves, Heloísa Mazotti Lopes; Garcia, Cássia Virginia; Trein, Márcia Rodrigues; Nardi, Nance Beyer; Schapoval, Elfrides Eva Scherman; Steppe, Martin

2012-05-15

286

Characterisation and comparison of the uptake of ionizable and polar pesticides, pharmaceuticals and personal care products by POCIS and Chemcatchers.  

PubMed

Growing concern about the environmental impact of ionizable and polar organic chemicals such as pesticides, pharmaceuticals and personal care products has lead to the inclusion of some in legislative and regulatory frameworks. It is expected that future monitoring requirements for these chemicals in aquatic environments will increase, along with the need for low cost monitoring and risk assessment strategies. In this study the uptake of 13 neutral and 6 ionizable pesticides, pharmaceuticals and personal care products by modified POCIS (with Strata™-X sorbent) and Chemcatchers™ (SDB-RPS or SDB-XC) was investigated under controlled conditions at pH = 6.5 for 26 days. The modified POCIS and Chemcatcher™ (SDB-RPS) samplers exhibited similar performance with the uptake of the majority of the 19 chemicals of interest categorised as linear over the 26 day deployment. Only a few ionized herbicides (picloram and dicamba) and triclosan showed negligible accumulation. Chemcatcher™ with SDB-XC sorbent performed relatively poorly with only carbamazepine having a linear accumulation profile, and 8 compounds showing no measurable accumulation. Differences in the uptake behavior of chemicals were not easily explained by their physico-chemical properties, strengthening the requirement for detailed calibration data. PES membranes accumulated significant amount of some compounds (i.e. triclosan and diuron), even after extended deployment (i.e. 26 days). At present there is no way to predict which compounds will demonstrate this behavior. Increasing membrane pore size from 0.2 to 0.45 ?m for Chemcatcher™ (SBD-RPS) caused an average increase in Rs of 24%. PMID:25208684

Kaserzon, S L; Hawker, D W; Kennedy, K; Bartkow, M; Carter, S; Booij, K; Mueller, J F

2014-10-20

287

Bacterial secondary production on vascular plant detritus: relationships to detritus composition and degradation rate.  

PubMed Central

Bacterial production at the expense of vascular plant detritus was measured for three emergent plant species (Juncus effusus, Panicum hemitomon, and Typha latifolia) degrading in the littoral zone of a thermally impacted lake. Bacterial secondary production, measured as tritiated thymidine incorporation into DNA, ranged from 0.01 to 0.81 microgram of bacterial C mg of detritus-1 day-1. The three plant species differed with respect to the amount of bacterial productivity they supported per milligram of detritus, in accordance with the predicted biodegradability of the plant material based on initial nitrogen content, lignin content, and C/N ratio. Bacterial production also varied throughout the 22 weeks of in situ decomposition and was positively related to the nitrogen content and lignin content of the remaining detritus, as well as to the temperature of the lake water. Over time, production was negatively related to the C/N ratio and cellulose content of the degrading plant material. Bacterial production on degrading plant material was also calculated on the basis of plant surface area and ranged from 0.17 to 1.98 micrograms of bacterial C cm-2 day-1. Surface area-based calculations did not correlate well with either initial plant composition or changing composition of the remaining detritus during decomposition. The rate of bacterial detritus degradation, calculated from measured production of surface-attached bacteria, was much lower than the actual rate of weight loss of plant material. This discrepancy may be attributable to the importance of nonbacterial organisms in the degradation and loss of plant material from litterbags or to the microbially mediated solubilization of particulate material prior to bacterial utilization, or both. PMID:2802603

Moran, M A; Hodson, R E

1989-01-01

288

Biodegradation of organophosphorus pesticides by soil bacteria  

NASA Astrophysics Data System (ADS)

A number of studies in the 1980s and 1990s showed that crop-protection products, applied to drained fields, could move downwards through the soil profile and to the groundwater. Organophosphorus insecticides (OPs) are used all over the world for crop protection, for other agricultural practices such as sheep dipping and, in aquaculture, for the control of sea lice. Ops besides showing a specific neurotoxicity and have also been related to various modern diseases, including Creutzfeldt-Jakob (CJD) and the Gulf War syndrome. Although OPs are less persistent than Organoclorine pesticides (OCs), they still constitute an environmental risks thus increasing the social concern about their levels in soils, surface waters, and ground waters. Degradation of OPs by microorganisms has been assessed for a few bacterial strains. In the present study the OPs degrading potential of indigenous soil microorganisms was investigated. Using enrichment cultures in which parathion was the only C and energy sources many bacterial strains were isolated from OPs contaminated and pristine agricultural soils characterized by different physico-chemical properties. More than 40 potential OPs degraders were isolated and grouped in operational taxonomic units (OTU) using analysis of polymorphism showed by the ribosomal internal transcribed spacer (ITS). Partial sequencing of 16S rRNA gene of representative isolates of each OTU revealed that most of them belong to Proteobacteria and Actinobacteria. All the analyzed soils showed the presence of putative OPs degraders: the highest diversity was found in organic cultivated soils, the lowest in chemically cultivated soils. Degradation of different OPs, characterized by different physical and chemical properties, was obtained by different selected representative strains using SPME GC-MS analysis on water and soil microcosms. The results showed that, after the incubation period, the amount of pesticide residues were in the range 20-80%. Some of the isolates bacterial species are currently unknown as OPs degraders.

de Pasquale, C.; Fodale, R.; Lo Piccolo, L.; Palazzolo, E.; Alonzo, G.; Quatrini, P.

2009-04-01

289

RNA interference of influenza virus production by directly targeting mRNA for degradation and  

E-print Network

RNA interference of influenza virus production by directly targeting mRNA for degradation. Eisen, December 23, 2002 Influenza A virus causes widespread infection in the human respi- ratory tract, but existing vaccines and drug therapy are of limited value. Here we show that short interfering RNAs (si

Gleeson, Joseph G.

290

LC\\/MS for the degradation profiling of cough–cold products under forced conditions  

Microsoft Academic Search

Heat, acid, base, UV radiation and oxidation stress methods were applied to study the stability of cough–cold products containing acetaminophen, phenylephrine or phenylpropanolamine hydrochloride and chlorpheniramine maleate. Liquid chromatography coupled with mass spectrometry was used to analyze the degraded samples and obtain molecular weights information. Different volatile buffers (ammonium bicarbonate and ammonium acetate) were assayed in LC\\/MS methods and retention

A. Mar??n; C. Barbas

2004-01-01

291

Detecting and quantifying lewisite degradation products in environmental samples using arsenic speciation  

SciTech Connect

This report describes a unique method for identifying and quantifying lewisite degradation products using arsenic (III) and arsenic (IV) speciation in solids and in solutions. Gas chromatographic methods, as well as high-performance liquid chromatographic methods are described for separation of arsenic species. Inductively coupled plasma-mass spectrographic methods are presented for the detection of arsenic.

Bass, D.A.; Yaeger, J.S.; Kiely, J.T.; Crain, J.S.; Shem, L.M.; O`Neill, H.J.; Gowdy, M.J. [Argonne National Lab., IL (United States); Besmer, M.; Mohrman, G.B. [Rocky Mountain Arsenal, Commerce City, CO (United States)

1995-12-31

292

Glucosinolate degradation products, alkanes and fatty acids from plants and cell cultures of Descurainia sophia  

Microsoft Academic Search

Allyl and 3-butenyl isothiocyanate with two nitriles and an epithiobutane derivative were estimated. These glucosinolate degradation products were found in callus, seed, and dried plant but not in suspension cultures. Seventeen alkanes and five fatty acids were also identified and estimated in plant material and cultures. 4-Methylthiobutyl and 2-phenylethyl isothiocyanates were also detected in seeds. Incubation of cultures at 4°

S. Afsharypuor; G. B. Lockwood

1985-01-01

293

The role of purine degradation in methane biosynthesis and energy production in Methanococcus vannielii  

Microsoft Academic Search

This paper contains the specific goals of this proposal and is a summary of the progress toward that specific goal. These goals include: survey of other methanogens to assess purine degradation, isolation and characterization of the enzyme and the products of the formiminoglycine cleavage reaction in methanococcus vannielii, ascertaining of the metabolic fate of glycine formed from the cleavage of

DeMoll

1989-01-01

294

Thermal degradation of municipal plastic waste for production of fuel-like hydrocarbons  

Microsoft Academic Search

Fuel-like utilization is one way of chemical recycling of liquids from waste polymers. The degradation of different mixtures of the most frequently occurring waste polymers (polyethylene, polypropylene, polystyrene, polyamide, ethylene-propylene copolymer and polyurethane rubber) was investigated in a horizontal tube reactor. The effects of cracking temperature and residence time on the yields and structure of the products were studied. The

N. Miskolczi; L. Bartha; G. Deák; B. Jóver

2004-01-01

295

In vitro cytotoxic and genotoxic effects of diphenylarsinic acid, a degradation product of chemical warfare agents  

Microsoft Academic Search

Diphenylarsinic acid [DPAs(V)], a degradation product of diphenylcyanoarsine or diphenylchloroarsine, both of which were developed as chemical warfare agents, was investigated in terms of its capacity to induce cytotoxic effects, numerical and structural changes of chromosomes, and abnormalities of centrosome integrity and spindle organizations in conjunction with the effects of glutathione (GSH) depletion. DPAs(V) had toxic effects on cultured human

Takafumi Ochi; Toshihide Suzuki; Hideo Isono; Toshikazu Kaise

2004-01-01

296

Analytical methods for environmental sampling of chemical warfare agents and their degradation products  

Microsoft Academic Search

This first technical conference promoted the standardization of analytical procotols to reliably detect chemical warfare agents and their degradation products in soil, water, and other complex environmental media. This supports the various chemical weapons disposal and emergency preparedness programs, Chemical Weapons Convention treaty compliance, installation restoration and base closure decisions. Five major topics were addressed: Implementation for treaty compliance, installation,

A. P. Watson; S. Kistner

1995-01-01

297

Derivatisation reactions in the chromatographic analysis of chemical warfare agents and their degradation products  

Microsoft Academic Search

The analysis of chemical warfare agents and their degradation products is an important component of verification of compliance with the Chemical Weapons Convention. Gas and liquid chromatography, particularly combined with mass spectrometry, are the major techniques used to detect and identify chemicals of concern to the Convention. The more polar analytes, and some of the more reactive or highly volatile

Robin M Black; Bob Muir

2003-01-01

298

Molecularly imprinted polymer-based potentiometric sensor for degradation product of chemical warfare agents  

Microsoft Academic Search

A biomimetic potentiometric sensor for the specific recognition of methylphosphonic acid (MPA), the degradation product of nerve agents sarin, soman, VX, etc., was designed. This involves the preparation of MPA imprinted polymer particles and removal of the template by soxhlet extraction. Subsequently, the leached MIP particles were dispersed in 2-nitrophenyloctyl ether (plasticizer) and embedded in polyvinyl chloride matrix. The sensor

K. P. Prathish; K. Prasad; T. Prasada Rao; M. V. S. Suryanarayana

2007-01-01

299

Resource degradation, technical change, and the productivity of energy use in U.S. agriculture  

Microsoft Academic Search

Two important issues surrounding future food production are the reliance of industrial agriculture on large quantities of fossil fuels and the degree to which technical change and farm management can offset degradation in the form of soil erosion, groundwater depletion, reduced genetic diversity, pest resistance, and so on. This analysis uses new and more consistent data on energy use in

Cutler J. Cleveland

1995-01-01

300

HYDROLOGIC CONDITIONS AFFECTING THE TROPOSPHERIC FLUX OF VINCLOZOLIN AND ITS DEGRADATION PRODUCTS  

EPA Science Inventory

A laboratory chamber was used to determine hydrologic conditions that lead to the tropospheric flux of a suspected anti-androgenic dicarboximide fungicide, vinclozolin (3-(3,5-dichlorophenyl)-5-methyl-5-vinyl-oxzoli-dine-2,4-dione) and three degradation products from sterilized...

301

Reduction of matrix effects and improvement of sensitivity during determination of two chloridazon degradation products in aqueous matrices by using UPLC-ESI-MS/MS.  

PubMed

The development and validation of a sensitive and reliable detection method for the determination of two polar degradation products, desphenyl-chloridazon (DPC) and methyl-desphenyl-chloridazon (MDPC) in surface water, ground water and drinking water is presented. The method is based on direct large volume injection ultra-performance liquid chromatography electrospray tandem mass spectrometry. This simple but powerful analytical method for polar substances in the aquatic environment is usually hampered by varying matrix effects, depending on the nature of different water bodies. For the two examined degradation products, the matrix effects are particularly strong compared with other polar degradation products of pesticides. Therefore, matrix effects were studied thoroughly with the aim of minimising them and improving sensitivity during determination by postcolumn addition of ammonia solution as a modifier. An internal standard was used in order to compensate for remaining matrix effects. The calibration curve shows very good coefficients of correlation (0.9994 for DPC and 0.9999 for MDPC). Intraday precision values were lower than 5 % for DPC, 3 % for MDPC and the limits of detection were 10 ng/L for both substances. The method was successfully used in a national round robin test with a deviation between 3 and 8 % from target values. Finally, about 1,000 samples from different water bodies have been examined with this method in the Rhine and Ruhr region of North-Rhine-Westphalia (Germany) and in the European Union. Approximately 76 % of analysed samples contained measurable amounts of DPC at concentrations up to 8 ?g/L while 53 % of the samples showed MDPC concentrations up to 2.3 ?g/L. PMID:22526659

Kowal, Sebastian; Balsaa, Peter; Werres, Friedrich; Schmidt, Torsten C

2012-06-01

302

Pesticide biotransformation and fate in heterogeneous environments  

Microsoft Academic Search

The effects and relative impacts of environmental variables on the behaviour of pesticides, through the effect on pesticide-degrading microorganisms, was studied in a broad spectrum and covered the most relevant emission routes. It is shown that the effect of landscape geochemistry, which is a pre-set condition in an agricultural management, may be significant (chapter 2). Adjoining soil types, which occur

J. P. M. Vink

1997-01-01

303

Superoxide mediated production of hydroxyl radicals by magnetite nanoparticles: demonstration in the degradation of 2-chlorobiphenyl.  

PubMed

Increasing attention has been paid to magnetite nanoparticles (MNPs) due to their highly reductive reactivity toward environmental contaminants. However, there is little information related to the generation of reactive oxygen species (ROS) by MNPs, which in fact plays a vital role for the transformation of contaminants. In this paper, the degradation of 2-chlorobiphenyl (2-CB) by MNPs was investigated. The role of ROS generated by MNPs in this process was elucidated. The results demonstrated that hydroxyl radicals (OH) generated by MNPs at low pH could efficiently degrade 2-CB. The mechanism of the formation of OH by MNPs was divided into two steps: (i) the superoxide radical anion (O2(-)) mediated production of hydrogen peroxide (H2O2), and (ii) the reaction of formed H2O2 with Fe(II) dissolved from MNPs to produce OH through Fenton reaction. Comparison of the degradation products of 2-CB by MNPs with MNPs/ethanol and Fenton reagents further supported the involvement of OH in the degradation of 2-CB. The degradation efficiency of 2-CB by MNPs under acidic conditions was higher than that in alkaline solution. These findings provide a new insight into the understanding of reactivity of MNPs for the transformation of 2-CB and possibly other relevant environmental contaminants. PMID:23434481

Fang, Guo-Dong; Zhou, Dong-Mei; Dionysiou, Dionysios D

2013-04-15

304

Pesticide Residues1 Frederick M. Fishel2  

E-print Network

PI-69 Pesticide Residues1 Frederick M. Fishel2 1. This document is PI-69, one of a series, Agronomy Department, and director, Pesticide Information Office; UF/IFAS Extension, Gainesville, FL 32611 not signify our approval to the exclusion of other products of suitable composition. Use pesticides safely

Watson, Craig A.

305

Applying pesticides  

NSDL National Science Digital Library

Fertilizer is one way to provide crops with the nutrients they need. Pesticides can also be applied to crops to keep them healthy and free of insects. However, applying too much fertilizer or pesticide protection could harm the environment and organisms.

Scott Bauer (USDA-ARS;Yakima Agricultural Research Laboratory)

2006-05-23

306

Spatial modeling of personalized exposure dynamics: the case of pesticide use in small-scale agricultural production landscapes of the developing world  

PubMed Central

Background Pesticide poisoning is a global health issue with the largest impacts in the developing countries where residential and small-scale agricultural areas are often integrated and pesticides sprayed manually. To reduce health risks from pesticide exposure approaches for personalized exposure assessment (PEA) are needed. We present a conceptual framework to develop a spatial individual-based model (IBM) prototype for assessing potential exposure of farm-workers conducting small-scale agricultural production, which accounts for a considerable portion of global food crop production. Our approach accounts for dynamics in the contaminant distributions in the environment, as well as patterns of movement and activities performed on an individual level under different safety scenarios. We demonstrate a first prototype using data from a study area in a rural part of Colombia, South America. Results Different safety scenarios of PEA were run by including weighting schemes for activities performed under different safety conditions. We examined the sensitivity of individual exposure estimates to varying patterns of pesticide application and varying individual patterns of movement. This resulted in a considerable variation in estimates of magnitude, frequency and duration of exposure over the model runs for each individual as well as between individuals. These findings indicate the influence of patterns of pesticide application, individual spatial patterns of movement as well as safety conditions on personalized exposure in the agricultural production landscape that is the focus of our research. Conclusion This approach represents a conceptual framework for developing individual based models to carry out PEA in small-scale agricultural settings in the developing world based on individual patterns of movement, safety conditions, and dynamic contaminant distributions. The results of our analysis indicate our prototype model is sufficiently sensitive to differentiate and quantify the influence of individual patterns of movement and decision-based pesticide management activities on potential exposure. This approach represents a framework for further understanding the contribution of agricultural pesticide use to exposure in the small-scale agricultural production landscape of many developing countries, and could be useful to evaluate public health intervention strategies to reduce risks to farm-workers and their families. Further research is needed to fully develop an operational version of the model. PMID:19331690

Leyk, Stefan; Binder, Claudia R; Nuckols, John R

2009-01-01

307

Diagnostic possibilities of specific fibrin(ogen) degradation products in relation to venous thromboembolism.  

PubMed

The exclusion of deep venous thrombosis (DVT) in the elderly is hampered by low specificity in clinical decision of D-dimer assays in older patients. To reduce false-positive results, we evaluated specific fibrin(ogen) degradation product assays for their contribution in the diagnosis of DVT. In a post-hoc study with outpatients suspected for DVT, we evaluated the elastase-specific fibrinogen (fibrinogen elastase degradation product, FgEDP) and D-E-specific fibrin (fibrin degradation product, FbDP) degradation product assays in relation to DVT. Results were combined with five D-dimer assays as ratio, with a specific focus on age-dependency. In 437 patients (DVT prevalence 39%), FgEDP correlated with D-dimer in DVT-negative patients (P<0.001), but not in DVT-positive patients (P?>?0.55). FbDP results correlated with D-dimer in both groups (P<0.001). The values of the area under the curve of the receiver operating characteristic curve for both assays were lower than D-dimer. Using the ratios, only in the fourth age quartile D-dimer/FgEDP ratios had diagnostic value with lower number needed to test (1.8-12.7) as compared to D-dimer less than 500 ?g/l alone (5.4-102). The D-dimer/FbDP ratios in DVT-negative elderly patients increased to a plateau by increasing D-dimer. In DVT-positive patients, these ratios were near constant for increasing values of D-dimer. In elderly patients, the D-dimer/FgEDP ratios may improve the number of patients in whom DVT could be excluded. The D-dimer/FbDP ratios showed differences in composition of fibrin degradation products between DVT-negative and DVT-positive patients and between young and old DVT-negative patients. PMID:23187785

Haas, Fred J L M; Schutgens, Roger E G; Biesma, Douwe H; Laterveer, Ria H; Kluft, Cornelis

2013-04-01

308

Repression and recuperation of brood production in Bombus terrestris bumble bees exposed to a pulse of the neonicotinoid pesticide imidacloprid.  

PubMed

Currently, there is concern about declining bee populations and some blame the residues of neonicotinoid pesticides in the nectar and pollen of treated crops. Bumble bees are important wild pollinators that are widely exposed to dietary neonicotinoids by foraging in agricultural environments. In the laboratory, we tested the effect of a pulsed exposure (14 days 'on dose' followed by 14 days 'off dose') to a common neonicotinoid, imidacloprid, on the amount of brood (number of eggs and larvae) produced by Bombus terrestris L. bumble bees in small, standardised experimental colonies (a queen and four adult workers). During the initial 'on dose' period we observed a dose-dependent repression of brood production in colonies, with productivity decreasing as dosage increased up to 98 µg kg(-1) dietary imidacloprid. During the following 'off dose' period, colonies showed a dose-dependent recuperation such that total brood production during the 28-day pulsed exposure was not correlated with imidacloprid up to 98 µg kg(-1). Our findings raise further concern about the threat to wild bumble bees from neonicotinoids, but they also indicate some resilience to a pulsed exposure, such as that arising from the transient bloom of a treated mass-flowering crop. PMID:24224015

Laycock, Ian; Cresswell, James E

2013-01-01

309

Repression and Recuperation of Brood Production in Bombus terrestris Bumble Bees Exposed to a Pulse of the Neonicotinoid Pesticide Imidacloprid  

PubMed Central

Currently, there is concern about declining bee populations and some blame the residues of neonicotinoid pesticides in the nectar and pollen of treated crops. Bumble bees are important wild pollinators that are widely exposed to dietary neonicotinoids by foraging in agricultural environments. In the laboratory, we tested the effect of a pulsed exposure (14 days ‘on dose’ followed by 14 days ‘off dose’) to a common neonicotinoid, imidacloprid, on the amount of brood (number of eggs and larvae) produced by Bombus terrestris L. bumble bees in small, standardised experimental colonies (a queen and four adult workers). During the initial ‘on dose’ period we observed a dose-dependent repression of brood production in colonies, with productivity decreasing as dosage increased up to 98 µg kg?1 dietary imidacloprid. During the following ‘off dose’ period, colonies showed a dose-dependent recuperation such that total brood production during the 28-day pulsed exposure was not correlated with imidacloprid up to 98 µg kg?1. Our findings raise further concern about the threat to wild bumble bees from neonicotinoids, but they also indicate some resilience to a pulsed exposure, such as that arising from the transient bloom of a treated mass-flowering crop. PMID:24224015

Laycock, Ian; Cresswell, James E.

2013-01-01

310

Characterization of radiolytically generated degradation products in the strip section of a TRUEX flowsheet  

SciTech Connect

This report presents a summary of the work performed to meet the FCRD level 2 milestone M3FT-13IN0302053, “Identification of TRUEX Strip Degradation.” The INL radiolysis test loop has been used to identify radiolytically generated degradation products in the strip section of the TRUEX flowsheet. These data were used to evaluate impact of the formation of radiolytic degradation products in the strip section upon the efficacy of the TRUEX flowsheet for the recovery of trivalent actinides and lanthanides from acidic solution. The nominal composition of the TRUEX solvent used in this study is 0.2 M CMPO and 1.4 M TBP dissolved in n-dodecane and the nominal composition of the TRUEX strip solution is 1.5 M lactic acid and 0.050 M diethylenetriaminepentaacetic acid. Gamma irradiation of a mixture of TRUEX process solvent and stripping solution in the test loop does not adversely impact flowsheet performance as measured by stripping americium ratios. The observed increase in americium stripping distribution ratios with increasing absorbed dose indicates the radiolytic production of organic soluble degradation compounds.

Dean R. Peterman; Lonnie G. Olson; Gary S. Groenewold; Rocklan G. McDowell; Richard D. Tillotson; Jack D. Law

2013-08-01

311

Analysis of degradation products of PAH and PCP using electrospray ionization mass spectrometry  

SciTech Connect

Bioremediation is an important strategy for the clean-up of hazardous waste sites. In the past, assessing the efficacy of bioremediation techniques has involved monitoring the disappearance of the pollutant with minimal regard to the products formed via microbial degradation of the initial contaminant. Aromatic hydrocarbons in the environment are subject to oxidation by a variety of mechanisms including photooxidation, microbial degradation and metabolism by higher organisms. These processes result in an array of oxygenated products including hydroxylated aromatics, ketones, quinones, and acids. In many animals, metabolically activated PAH bind covalently to cellular species including sulfate, glucuronic acid, glutathione, as well as proteins and DNA. In some cases, the oxygenated species have been shown to be more highly toxic than the parent hydrocarbon. Measures directed at either controlling the migration of toxic microbial metabolites, or precluding their formation in the first place, can be developed intelligently if the chemical characteristics of the toxic can be determined. It is, therefore, desirable to characterize fully the degradation products present in environmental samples not only as a means of elucidating the degradation pathways, but in order to assess the full hazard represented by the contamination and the effectiveness of the clean-up protocols employed. Conventional GC/MS techniques often require extensive sample clean-up and fractionation, while the more polar metabolites are intractable to GC altogether. Since electrospray ionization is well suited to analysis of such polar nonvolatile compounds, as well as compatible with HPLC clean-up and separations, the authors are applying this technique to the analysis of polar degradation products of aromatic hydrocarbons including polycyclic aromatic hydrocarbons and chlorinated phenols.

Pavlovich, J.G.; Stringfellow, W.; Kazunga, Chikoma; Aitken, M.D.; Charles, M.J. [Univ. of North Carolina, Chapel Hill, NC (United States)

1994-12-31

312

Rates and products of degradation for MTBE and other oxygenate fuel additives in the subsurface environment  

SciTech Connect

The recent realization that oxygenated fuel additives such as MTBE are becoming widely distributed groundwater contaminants has created a sudden and pressing demand for data on the processes that control their environmental fate. Explaining and predicting the subsequent environmental fate of these compounds is going to require extrapolations over long time frames that will be very sensitive to the quality of input data on each compound. To provide such data, they have initiated a systematic study of the pathways and kinetics of fuel oxygenate degradation under subsurface conditions. Batch experiments in simplified model systems are being performed to isolate specific processes that may contribute to MTBE degradation. A variety of degradation pathways can be envisioned that lead to t-butyl alcohol (TBA) as the primary or secondary product. However, experiments to date with a facultative iron reducing bacteria showed no evidence for TBA formation. Continuing experiments include mixed cultures from a range of aquifer materials representative of NAWQA study sites.

Tratnyek, P.G.; Church, C.D.; Pankow, J.F. [Oregon Graduate Inst., Portland, OR (United States). Dept. of Environmental Science and Engineering

1995-12-31

313

Ethanol production by Saccharomyces cerevisiae using lignocellulosic hydrolysate from Chrysanthemum waste degradation.  

PubMed

Ethanol production derived from Saccharomyces cerevisiae fermentation of a hydrolysate from floriculture waste degradation was studied. The hydrolysate was produced from Chrysanthemum (Dendranthema grandiflora) waste degradation by Pleurotus ostreatus and characterized to determine the presence of compounds that may inhibit fermentation. The products of hydrolysis confirmed by HPLC were cellobiose, glucose, xylose and mannose. The hydrolysate was fermented by S. cerevisiae, and concentrations of biomass, ethanol, and glucose were determined as a function of time. Results were compared to YGC modified medium (yeast extract, glucose and chloramphenicol) fermentation. Ethanol yield was 0.45 g g(-1), 88 % of the maximal theoretical value. Crysanthemum waste hydrolysate was suitable for ethanol production, containing glucose and mannose with adequate nutrients for S. cerevisiae fermentation and low fermentation inhibitor levels. PMID:23117675

Quevedo-Hidalgo, Balkys; Monsalve-Marín, Felipe; Narváez-Rincón, Paulo César; Pedroza-Rodríguez, Aura Marina; Velásquez-Lozano, Mario Enrique

2013-03-01

314

Acetamide herbicides and their degradation products in ground water and surface water of the United States, 1993-2003  

USGS Publications Warehouse

During 1993 through 2003, the U.S. Geological Survey conducted a number of studies to investigate and document the occurrence, fate, and transport of acetamide herbicides and their degradation products in ground and surface water. As part of these studies, approximately 5,100 water samples were collected and analyzed for the acetamide parent herbicides acetochlor, alachlor, dimethenamid, flufenacet, and metolachlor and their degradation products ethanesulfonic acid, oxanilic acid, and sulfinyl acetic acid. During this period, various analytical methods were developed to detect and measure concentrations of acetamide herbicides and their degradation products in ground water and surface water. Results showed that the degradation products of acetamide herbicides in ground water were detected more frequently and occurred at higher concentrations than their parent compounds. Further study showed that the acetamide herbicides and their degradation products were detected more frequently in surface water than in ground water. In general, the parent compounds were detected at similar or greater frequencies than the degradation products in surface water. The developed methods and data were valuable for acquiring information about the occurrence, fate, and transport of the herbicides and their degradation products and the importance of analyzing for both parent compounds and their degradate products in water-quality studies.

Scribner, Elisabeth A.; Dietze, Julie E.; Thurman, Michael

2004-01-01

315

Biodegradation of the Alkaline Cellulose Degradation Products Generated during Radioactive Waste Disposal  

PubMed Central

The anoxic, alkaline hydrolysis of cellulosic materials generates a range of cellulose degradation products (CDP) including ? and ? forms of isosaccharinic acid (ISA) and is expected to occur in radioactive waste disposal sites receiving intermediate level radioactive wastes. The generation of ISA's is of particular relevance to the disposal of these wastes since they are able to form complexes with radioelements such as Pu enhancing their migration. This study demonstrates that microbial communities present in near-surface anoxic sediments are able to degrade CDP including both forms of ISA via iron reduction, sulphate reduction and methanogenesis, without any prior exposure to these substrates. No significant difference (n?=?6, p?=?0.118) in ? and ? ISA degradation rates were seen under either iron reducing, sulphate reducing or methanogenic conditions, giving an overall mean degradation rate of 4.7×10?2 hr?1 (SE±2.9×10?3). These results suggest that a radioactive waste disposal site is likely to be colonised by organisms able to degrade CDP and associated ISA's during the construction and operational phase of the facility. PMID:25268118

Rout, Simon P.; Radford, Jessica; Laws, Andrew P.; Sweeney, Francis; Elmekawy, Ahmed; Gillie, Lisa J.; Humphreys, Paul N.

2014-01-01

316

Strategies for assessing children's organophosphorus pesticide exposures in agricultural communities  

Microsoft Academic Search

Children can be exposed to pesticides from multiple sources and through multiple pathways. In addition to the standard pathways of diet, drinking water and residential pesticide use, children in agricultural communities can be exposed to pesticides used in agricultural production. A research program on children and pesticides was established at the University of Washington (UW) in 1991 and has focused

RICHARD A FENSKE; CHENSHENG LU; NANCY J SIMCOX; CARRIE LOEWENHERZ; JENNIFER TOUCHSTONE; THOMAS F MOATE; EMILY H ALLEN; JOHN C KISSEL

2000-01-01

317

Biodegradation of type II pyrethroids and major degraded products by a newly isolated Acinetobacter sp. strain JN8.  

PubMed

A Gram-negative aerobic bacterium, designated as JN8, was isolated from activated sludge and soil in a pesticides factory in China. It was found that JN8 had a high capacity for degrading a broad range of type II pyrethroids and utilizing these pyrethroids as the sole carbon source for cell growth. The degradation rates of a 100 mg·L(-1) concentration of ?-cypermethrin, cypermethrin, fenpropathrin, fenvalerate, and deltamethrin by JN8 in mineral salt medium were 74.1%, 64.9%, 57.9%, 48.1% and 34.9%, respectively. Strain JN8 was identified as a species of Acinetobacter based on its biochemical properties and 16S rRNA sequence analysis. ?-Cypermethrin was degraded by JN8 through hydrolysis of the carboxylester linkage to form 3-phenoxybenzoic acid and 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid, both of which could be further degraded by JN8. JN8 is the first strain of an Acinetobacter species in which pyrethoid-degrading activity has been detected, and such a feature makes it a potential resource for disposal of waste and effluent from pyrethroid manufacturing facilities. PMID:25083550

Jin, Zhaoxia; Guo, Qiong; Zhang, Zongshen; Yan, Tongshuai

2014-08-01

318

Evaluation of the pesticide contamination of groundwater sampled over two years from a vulnerable zone in Portugal.  

PubMed

A monitoring program of pesticides was implemented in the "ZV1" vulnerable zone (Directive 91/676/EEC) in Portugal, in order to assess the impact of intensive horticulture practices on groundwater contamination. The monitoring network comprised 23 sampling points sampled every 3 months during a 2-year period. Forty-two pesticides belonging to varied chemical families, including current pesticides, persistent organic pollutants (POPs), and degradation products, were analyzed by solid-phase microextraction (SPME) and gas chromatography with electron-capture detection-thermoionic specific detection (GC-ECD-TSD) or mass spectrometry (GC-MS). Statistical treatment was performed by descriptive analysis followed by chemometric multivariate analysis. The latter included cluster analysis, linear discriminant analysis, and factor analysis. Twenty-two pesticides were quantitated, 20 pesticides were not detected, and metalaxyl, benalaxyl, quinalphos, pirimicarb, and prometryn were only qualitatively detected. The most frequently detected pesticides (% of samples analyzed) were lindane (53%), pendimethalin (49%), endosulfan sulfate (44%), and endosulfan (38%) while those that most frequently exceeded the 0.1 mug L-1 European Union (EU) limit were pendimethalin (13%), endosulfan (12%), endosulfan sulfate (11%), and atrazine (9%). 45% of the samples exceeded the EU limit for individual pesticides while 27% exceeded the limit set to the sum of pesticides (0.5 mug L-1). Principal component analysis revealed five principal components that were attributed to environmental/agrochemical managing factors. The broad range of pesticides investigated combined with the intensive character of the local agriculture contributed to the diversity of pesticides that were detected. However, the frequency of pesticides above the EU regulatory limit is comparable to that found in the literature concerning different Portuguese and European regions. PMID:17608425

Gonçalves, Carlos M; Silva, Joaquim C G Esteves da; Alpendurada, Maria F

2007-07-25

319

[Study of multi-residue method for determining pesticide residues in processed foods manufactured from agricultural products by LC-MS/MS].  

PubMed

A rapid multi-residue method for determination of pesticide residues in processed foods manufactured from agricultural products was examined. Five mL water was added to 5 g sample in a polypropylene tube, and the tube was left to stand at room temperature for 30 min. Then, 20 mL acetonitrile was added to the sample. The mixture was homogenized in a high-speed homogenizer, followed by salting out with 1 g NaCl and 4 g anhydrous MgSO4. After centrifugation, the organic layer was purified on a graphitized carbon/PSA cartridge column. After removal of the solvent, the extract was resolved in methanol-water and analyzed with LC-MS/MS. The recoveries of 93 pesticides fortified into 5 kinds of processed foods [Chinese cabbage kimchi, marmalade, raisin, umeboshi (pickled plum) and worcester sauce] were examined at the concentrations of 0.02 and 0.1 ?g/g (n=5). The recoveries of 61 pesticides in all foods were 70-120% with relative standard deviation below 20% at both concentrations. Seventy-four processed foods obtained from markets in Japan were examined with this method. Pesticide residues over the maximum residue limit (0.01 ?g/g) were detected in 2 processed foods. PMID:24389475

Fukui, Naoki; Takatori, Satoshi; Kitagawa, Yoko; Okihashi, Masahiro; Kajimura, Keiji; Obana, Hirotaka

2013-01-01

320

[Fast screening ninety-six pesticides in six kinds of agricultural products by high performance liquid chromatography-quadrupole/electrostatic field orbit trap high-resolution mass spectrometry].  

PubMed

A high-throughput method for the determination of 96 pesticides in six kinds of agricultural products by liquid chromatography-quadrupole/electrostatic field orbit trap high-resolution mass spectrometry was developed. After extraction with 0.1% acetic acid in acetonitrile solution and concentration, dispersive solid-phase extraction was further utilized to reduce the matrix interference. The chromatographic analysis was performed on a C18 column with methanol and 5 mmol/L ammonium acetate solution as the mobile phases with a gradient elution program. The 96 pesticide residues were analyzed in switching positive and negative modes at the same time. With the optimized mass resolution, accurate mass-to-charge ratio extraction of the target pesticide compounds in full scan mode could eliminate matrix interference effectively. Two-stage threshold-triggered full mass scan mode was utilized to further improve the accuracy of qualitative analysis. The linear ranges of all the 96 pesticides were from 1 microg/L to 200 microg/L with correlation coefficients greater than 0.99. By detecting spiked samples, the detection limits were 5 microg/kg for all the residues and the recoveries were in the range of 58% - 105% with the relative standard deviations (RSDs) between 8.8% and 18.3%. PMID:23593881

Wu, Bin; Ding, Tao; Liu, Han; Chen, Huilan; Zhao, Zengyun; Zhang, Rui; Shen, Chongyu

2012-12-01

321

(Pesticide chemistry)  

SciTech Connect

This report summarizes a trip by L. W. Barnthouse of the Environmental Sciences Division (ESD), Oak Ridge National Laboratory (ORNL), to Hamburg, Federal Republic of Germany (FRG), where he participated in the 7th International Congress of Pesticide Chemistry. He chaired a workshop on experimental systems for determining effects of pesticides on nontarget organisms and gave an oral presentation at a symposium on pesticide risk assessment. Before returning to the United States, Dr. Barnthouse visited the Netherlands Institute for Sea Research in Texel, the Netherlands.

Barnthouse, L.W.

1990-09-04

322

Fate of CL-20 in sandy soils: degradation products as potential markers of natural attenuation.  

PubMed

Hexanitrohexaazaisowurtzitane (CL-20) is an emerging explosive that may replace the currently used explosives such as RDX and HMX, but little is known about its fate in soil. The present study was conducted to determine degradation products of CL-20 in two sandy soils under abiotic and biotic anaerobic conditions. Biotic degradation was prevalent in the slightly acidic VT soil, which contained a greater organic C content, while the slightly alkaline SAC soil favored hydrolysis. CL-20 degradation was accompanied by the formation of formate, glyoxal, nitrite, ammonium, and nitrous oxide. Biotic degradation of CL-20 occurred through the formation of its denitrohydrogenated derivative (m/z 393 Da) while hydrolysis occurred through the formation of a ring cleavage product (m/z 156 Da) that was tentatively identified as CH(2)=N-C(=N-NO(2))-CH=N-CHO or its isomer N(NO(2))=CH-CH=N-CO-CH=NH. Due to their chemical specificity, these two intermediates may be considered as markers of in situ attenuation of CL-20 in soil. PMID:18801604

Monteil-Rivera, Fanny; Halasz, Annamaria; Manno, Dominic; Kuperman, Roman G; Thiboutot, Sonia; Ampleman, Guy; Hawari, Jalal

2009-01-01

323

Study of degradation intermediates formed during electrochemical oxidation of pesticide residue 2,6-dichlorobenzamide (BAM) at boron doped diamond (BDD) and platinum-iridium anodes.  

PubMed

Electrochemical oxidation is a promising technique for degradation of otherwise recalcitrant organic micropollutants in waters. In this study, the applicability of electrochemical oxidation was investigated concerning the degradation of the groundwater pollutant 2,6-dichlorobenzamide (BAM) through the electrochemical oxygen transfer process with two anode materials: Ti/Pt90-Ir10 and boron doped diamond (Si/BDD). Besides the efficiency of the degradation of the main pollutant, it is also of outmost importance to control the formation and fate of stable degradation intermediates. These were investigated quantitatively with HPLC-MS and TOC measurements and qualitatively with a combined HPLC-UV and HPLC-MS protocol. 2,6-Dichlorobenzamide was found to be degraded most efficiently by the BDD cell, which also resulted in significantly lower amounts of intermediates formed during the process. The anodic degradation pathway was found to occur via substitution of hydroxyl groups until ring cleavage leading to carboxylic acids. For the BDD cell, there was a parallel cathodic degradation pathway that occurred via dechlorination. The combination of TOC with the combined HPLC-UV/MS was found to be a powerful method for determining the amount and nature of degradation intermediates. PMID:24873711

Madsen, Henrik Tćkker; Sřgaard, Erik Gydesen; Muff, Jens

2014-08-01

324

The use of live biocatalysts for pesticide detoxification  

Microsoft Academic Search

During the past decade, numerous microorganisms capable of degrading pesticides have been isolated, and detoxification processes based on these live biocatalysts have been developed. Recently, novel detoxification strategies using genetically engineered microorganisms with extended degradative capabilities have been investigated and, in some cases, shown to be more effective. One promising approach for the detoxification of organophosphate pesticides uses genetically engineered

Wilfred Chen; Ashok Mulchandani

1998-01-01

325

Light induced heterogeneous ozone processing on the pesticides adsorbed on silica particles  

NASA Astrophysics Data System (ADS)

In France, in 2010, the sales of pesticides reached 1.8 billion euros for 61 900 tons of active ingredients, positioning France as a first European consumer of pesticides, as reported by the European Crop Protection Association. About 19 million hectares of crops are sprayed annually with pesticides, i.e., 35% of the total surface area of France. This corresponds to an average pesticide dose of 3.2 kg ha-1. The consumption of herbicide and fungicide is favoured in comparison to the use of insecticides in France and the other European countries, as well. The partitioning of pesticides between the gas and particulate phases influences the atmospheric fate of these compounds such as their photo-chemical degradation. There is much uncertainty concerning the behavior of the pesticides in the atmosphere. Especially, there is a gap of knowledge concerning the degradation of the pesticides induced by heterogeneous reactions in absence and especially in presence of solar light. Considering that most of the pesticides currently used are semi-volatile, it is of crucial importance to investigate the heterogeneous reactivity of particulate pesticides with light and with atmospheric oxidants such as ozone and OH radical. The aim of the present work is to evaluate the light induced heterogeneous ozonation of suspended pesticide particles. 8 pesticides (cyprodinil, deltamethrin, difenoconazole, fipronil, oxadiazon, pendimethalin, permethrin and tetraconazole) were chosen for their physico-chemical properties and their concentration levels in the PACA (Région Provence-Alpes-Côte d'Azur) region, France. Silica particles with well-known properties were chosen as model particles of atmospheric relevance. Kinetic rate constants were determined to allow estimate the atmospheric lifetimes relating to ozone. The rate constants were determined as follows: k = (6.6 × 0.2) 10-19, (7.2 × 0.3) 10-19, (5.1 × 0.5) 10-19, (3.9 × 0.3) 10-19 [cm3 molecules-1 s-1] for Cyprodinil, delthamethrine, permethrine and pendimethaline, respectively. Concerning the other four pesticides under study i.e. difenoconazole, fipronil, oxadiazon and tetraconazole the obtained rate constants were extremely slow, < 3.9 10-19 [cm3 molecules-1 s-1]. In addition, we identified the condensed phase products in such heterogeneous reactions of ozone with the particulate pesticides by GC-MS coupled with the derivatization technique. The gas-phase products were followed on-line by PTR-MS-TOF. The obtained results will allow to recognize the impact of the pesticides and their degradation products on the human health, and to make recommendations in order to reduce population exposure to the pesticide plume. The results of this work will contribute to better describe and understand the pollution by phyto-sanitary products on the regional scale, which constitutes a necessary step in the development of environmental strategies. As a result the obtained results will help in the development of future environmental strategies to better understand and control phyto-sanitary product application and human exposure.

Socorro, J.; Désert, M.; Quivet, E.; Gligorovski, S.; Wortham, H.

2013-12-01

326

In situ rumen degradation and in vitro gas production of some selected grains from Turkey.  

PubMed

An investigation of the dry matter degradability (DMD) and effective dry matter degradability (EDDM) was performed for barley, wheat, rye, corn, triticale and oat samples, using the Nylon-bag technique. Gas production (GP), metabolizable energy (ME) and in vitro organic matter digestibility (IVOMD) were also studied by using Hohenheim gas test. The DM from barley, wheat, rye and triticale was digested rapidly in the rumen, and, at the 48 h of incubation, degradability was found to be approximately about 80%. The higher degradability observed for these grains than for oats and corn was attributable to the structure of these grains. In contrast, DM of corn and oats was degraded very slowly and reached 66.7 and 66.5 at 48 h, respectively. Effective degradability values of barley, wheat, rye, corn, triticale and oats were determined to be 61.4, 69.0, 64.0, 41.7, 66.7 and 58.6% in 5% rumen outflow rate, respectively. At the end of the 48 h incubation, total gas productions in barley, wheat, rye, corn, triticale and oats were estimated to be 83.6, 87.2, 87.5, 83.5, 85.8 and 63.9 ml/200 mg DM, respectively. The mean ME values of these grains calculated from cumulative gas amount at 24 h incubation were 11.8, 12.1, 12.3, 10.9, 12.4 and 10.2 MJ/kg DM, respectively. In vitro digestible organic matter of barley, wheat, rye, corn, triticale and oats were estimated to be 85.0, 87.3, 88.2, 79.5, 89.0 and 72.6%. Percentage overall EDDM (k=5%) of barley, wheat, rye, triticale and oats was positively correlated with in vitro GP at 6 h, cumulative GP at 24 h and total GP at 48 h (p<0.05). As a result, in situ dry matter degradation of grains showed great differences depending on the chemical compositions. In situ EDDM of grains may be predicted from in vitro gas production parameters. PMID:12452970

Umucalilar, H D; Co?kun, B; Gül?en, N

2002-10-01

327

Synergistic collaboration of gut symbionts in Odontotermes formosanus for lignocellulosic degradation and bio-hydrogen production.  

PubMed

In this work, gut microbes from the macrotermitine termite Odontotermes formosanus the cellulolytic Bacillus and fermentative Clostridium were studied in batch experiments using different carbon substrates to bio-mimic the termite gut for hydrogen production. Their fungus comb aging and the in vitro lignocellulosic degradation of the mango tree substrates by the synergistic interaction of Bacillus, Clostridium and Termitomyces were detected by Solid-state NMR. From the results, Bacillus species acted as a mutualist, by initiating an anaerobic environment for the growth of Clostridium, for bio-hydrogen production and the presence of Termitomyces enhanced the lignocellulosic degradation of substrates in vitro and in vivo. Thus, the synergistic collaboration of these three microbes can be used for termite-derived bio-fuel processing technology. PMID:23298769

Mathew, Gincy Marina; Mathew, Dony Chacko; Lo, Shou-Chen; Alexios, Georgy Mathew; Yang, Jia-Cih; Sashikumar, Jagathala Mahalingam; Shaikh, Tanveer Mahamadali; Huang, Chieh-Chen

2013-10-01

328

Biotic and abiotic degradation of illicit drugs, their precursor, and by-products in soil  

Microsoft Academic Search

This study presents the first systematic information on the degradation patterns of clandestine drug laboratory chemicals in soil. The persistence of five compounds – parent drugs (methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA)), precursor (pseudoephedrine), and synthetic by-products N-formylmethylamphetamine and 1-benzyl-3-methylnaphthalene) – were investigated in laboratory scale for 1year in three different South Australian soils both under non-sterile and sterile conditions. The results of

Raktim Pal; Mallavarapu Megharaj; K. Paul Kirkbride; Tunde Heinrich; Ravi Naidu

2011-01-01

329

Glucosinolate degradation products, alkanes and fatty acids from plants and cell cultures of Descurainia sophia.  

PubMed

Allyl and 3-butenyl isothiocyanate with two nitriles and an epithiobutane derivative were estimated. These glucosinolate degradation products were found in callus, seed, and dried plant but not in suspension cultures. Seventeen alkanes and five fatty acids were also identified and estimated in plant material and cultures. 4-Methylthiobutyl and 2-phenylethyl isothiocyanates were also detected in seeds. Incubation of cultures at 4° increased levels of the fatty acids but not isothiocyanates. PMID:24254078

Afsharypuor, S; Lockwood, G B

1985-12-01

330

The role of purine degradation in methane biosynthesis and energy production in Methanococcus vannielii  

SciTech Connect

This paper contains the specific goals of this proposal and is a summary of the progress toward that specific goal. These goals include: survey of other methanogens to assess purine degradation, isolation and characterization of the enzyme and the products of the formiminoglycine cleavage reaction in methanococcus vannielii, ascertaining of the metabolic fate of glycine formed from the cleavage of formiminoglycine, and elucidation of the route by which the formyl moiety of formiminoglycine is incorporated into the methane biosynthetic pathway.

DeMoll, E.

1989-10-30

331

Effects of modulators of the production and degradation of hydrogen peroxide on erythropoietin synthesis  

Microsoft Academic Search

Erythropoietin (Epo) synthesis is suppressed in normoxia and stimulated in hypoxia. To test the hypothesis that the cellular H2O2 level is important in the control of Epo synthesis, we have studied effects of modulators of H2O2 generation and degradation on Epo production in human hepatic cell cultures (hepatoma lines HepG2 and Hep3B). In addition, we measured the activities of antioxidant

O. Canbolat; J. Fandrey; W. Jelkmann

1998-01-01

332

Partial Transformation Products as Indicators of Microbial Hydrocarbon Degradation in Soils  

NASA Astrophysics Data System (ADS)

Monitored natural decay (intrinsic bioremediation), a cost-effective method for remediating contaminated property, is widely applied to fuel contaminated sites. If an intrinsic bioremediation approach could be supported for the clean up of polynuclear aromatic hydrocarbon (PAH) contaminated properties, millions of dollars in clean-up costs could potential be saved, especially in transfers of industrial properties that will continue to be used for industrial purposes. Proving intrinsic biodegradation of polynuclear aromatic hydrocarbons (PAHs) is problematic. Slow PAH biodegradation rates in contaminated soils mean that oxygen mass transfer rates into the soil exceeds bacterial oxygen demand. Likewise carbon dioxide production during degradation is sufficiently slow that carbon dioxide will not accumulate in the soil gas to levels exceeding background, uncontaminated soils. Therefore, oxygen depletion and carbon dioxide accumulation, typical indicators of intrinsic remediation activity at fuel contaminated sites, are of little use in demonstrating intrinsic PAH remediation. Additionally, direct measurement of PAH loss over time is of limited use in the absence of extensive historical records, especially at sites that are still emitting PAHs as part of their operations. PAH loss rates may be in the order of 10% per year, whereas combined sampling and analytical error can be greater than 50%. It is our hypothesis that PAH degradation products, such as aromatic carboxylic acids and dihydrodiols, will be present in soils where biodegradation is occurring and absent in soils that are biologically inactive. We have developed methods for the extraction of PAH biodegradation products from soils and the analysis of these metabolites by both gas chromatography and high performance liquid chromatography. We have tested our hypothesis against soils undergoing both active and passive bioremediation. Our results indicate that PAH degradation products are detectable in many soils and that the presence of metabolites is correlated with PAH degradation.

Stringfellow, W. T.

2001-12-01

333

Detection of simulants and degradation products of chemical warfare agents by vibrational spectroscopy  

Microsoft Academic Search

This work was focused in the measurement of spectroscopic signatures of Chemical Warfare Agent Simulants (CWAS) and degradation products of chemical agents using vibrational spectroscopy for the generation of spectroscopic libraries. The chemicals studied were: DMMP, DIMP, 2-CEES, 2-BAET, 1,4-thioxane, thiodiglycol sulfoxide, dihexylamine, cyclohexylamine, among others. Raman microscopy experiments were performed at different excitation wavelengths that spanned from NIR at

Orlando Ruiz-Pesante; Leonardo C. Pacheco-Londońo; Oliva M. Primera-Pedrozo; William Ortiz; Yadira M. Soto-Feliciano; Deborah E. Nieves; Michael L. Ramirez; Samuel P. Hernández-Rivera

2007-01-01

334

HPLC\\/ICP-OES determination of water-soluble silicone (PDMS) degradation products in leachates  

Microsoft Academic Search

Inductively coupled plasma optical emission spectrometry (ICP-OES) was used for the element-specific determination of water-soluble\\u000a organosilicon species separated by high-performance liquid chromatography (HPLC). Leachates from different waste deposit sites\\u000a were investigated. The polydimethylsiloxane (PDMS) degradation product dimethylsilanediol (DMSD) could be detected in almost\\u000a all samples in the low mg L–1 range, and it was furthermore possible to determine trimethylsilanol (TMSOL)

R. Grümping; A. V. Hirner

1999-01-01

335

Laboratory investigations into the effects of the pesticides mancozeb, chlorothalonil, and prosulfuron on nitrous oxide and nitric oxide production in fertilized soil  

Microsoft Academic Search

Independent soil microcosm experiments were used to investigate the effects of the fungicides mancozeb and chlorothalonil, and the herbicide prosulfuron, on N2O and NO production by nitrifying and denitrifying bacteria in fertilized soil. Soil cores were amended with NH4NO3 or NH4NO3 and pesticide, and the N2O and NO concentrations were monitored periodically for approximately 48h following amendment. Nitrification is the

Chad A. Kinney; Kevin W. Mandernack; Arvin R. Mosier

2005-01-01

336

Photo-assisted electrochemical detection (PAED) following HPLC-UV for the determination of nitro explosives and degradation products  

NASA Astrophysics Data System (ADS)

Continuous efforts implemented by government agencies such as the United States Geological Survey (USGS) aim to manage and protect the integrity of the environment's natural resources. RDX is one of the most frequently utilized nitramine explosives for mining, demolition and munitions purposes in the United States (US). The degradation of RDX in natural environments is of particular importance as a result of the accumulation of consequential degradation products in nature. Specifically, RDX has the potential to be degraded by microorganisms resulting in hazardous levels of harmful degradation products in soil and groundwater. The necessity for the detection of these particular degradation products is emphasized as a consequence of their toxicity as these products are recognized as potential mutagens. Photo-assisted electrochemical detection (PAED) following HPLC-UV is used to develop an analytical method qualified for the assessment of RDX and degradation products. The technique offers unique selectivity possessed by the photochemical reactor coupled to EC detection serving to eliminate the need for repetitive analysis using different column technologies. Furthermore, on-line sample pretreatment is developed and optimized specifically for the preparation of samples consisting of RDX and degradation products. Analytical figures of merit determined for all target analytes using on-line SPE-HPLC-UV-PAED revealed detection limits in the sub part per billion range for RDX and degradation product MEDINA. The effectiveness of the method is exemplified in collaborative studies with the USGS in monitoring the degradation of RDX and formation of degradation products once the nitro explosive is subject to anaerobic microorganisms WBC-2.

Fedorowski, J.; LaCourse, William R.; Lorah, Michelle M.

2012-06-01

337

Pesticide Toxicity Index: a tool for assessing potential toxicity of pesticide mixtures to freshwater aquatic organisms  

USGS Publications Warehouse

Pesticide mixtures are common in streams with agricultural or urban influence in the watershed. The Pesticide Toxicity Index (PTI) is a screening tool to assess potential aquatic toxicity of complex pesticide mixtures by combining measures of pesticide exposure and acute toxicity in an additive toxic-unit model. The PTI is determined separately for fish, cladocerans, and benthic invertebrates. This study expands the number of pesticides and degradates included in previous editions of the PTI from 124 to 492 pesticides and degradates, and includes two types of PTI for use in different applications, depending on study objectives. The Median-PTI was calculated from median toxicity values for individual pesticides, so is robust to outliers and is appropriate for comparing relative potential toxicity among samples, sites, or pesticides. The Sensitive-PTI uses the 5th percentile of available toxicity values, so is a more sensitive screening-level indicator of potential toxicity. PTI predictions of toxicity in environmental samples were tested using data aggregated from published field studies that measured pesticide concentrations and toxicity to Ceriodaphnia dubia in ambient stream water. C. dubia survival was reduced to ? 50% of controls in 44% of samples with Median-PTI values of 0.1–1, and to 0% in 96% of samples with Median-PTI values > 1. The PTI is a relative, but quantitative, indicator of potential toxicity that can be used to evaluate relationships between pesticide exposure and biological condition.

Nowell, Lisa H.; Norman, Julia E.; Moran, Patrick W.; Martin, Jeffrey D.; Stone, Wesley W.

2014-01-01

338

Sustainable agricultural practices: energy inputs and outputs, pesticide, fertilizer and greenhouse gas management.  

PubMed

The food security issue was addressed by the development of "modern agriculture" in the last century. But food safety issues and environment degradation were the consequences suffered as a result. Climate change has been recognized as the result of release of stored energy in fossil fuel into the atmosphere. Homogeneous crop varieties, machinery, pesticides and fertilizers are the foundation of uniform commodities in modern agriculture. Fossil fuels are used to manufacture fertilizers and pesticides as well as the energy source for agricultural machinery, thus characterizes modern agriculture. Bio-fuel production and the possibility of the agriculture system as a form of energy input are discussed. PMID:19965338

Wang, Yue-Wen

2009-01-01

339

Validated Stability-Indicating Chromatographic Methods for the Determination of Veralipride in Presence of Its Degradation Products  

Microsoft Academic Search

Two sensitive and selective chromatographic methods were developed and validated for determination of veralipride in presence\\u000a of its degradation products. Forced degradation studies were performed, using HCl, NaOH and 3% H2O2. The first method is based on thin-layer chromatographic separation of the intact drug spot from its degradation, followed\\u000a by densitometric measurements. The second method is based on isocratic liquid

Maissa Yacoub Salem; Nahla Nour El Din Salama; Lobna Mohammed Abd El Halim; Laila El-Sayed Abdel Fattah

2009-01-01

340

Microbially Mediated Degradation of Common Pharmaceuticals and Personal Care Products in Soil Under Aerobic and Reduced Oxygen Conditions  

Microsoft Academic Search

Biological degradation rates of estrogen compounds and common pharmaceutical and personal care products (PPCPs) were examined\\u000a in soils with a long history of exposure to these compounds through wastewater effluent and in soil not previously exposed.\\u000a Biological degradation rates over 14 days were compared under aerobic and anaerobic conditions. Estrogen compounds including\\u000a estrone, 17?-estradiol, estriol, and 17?-ethinylestradiol exhibited rapid degradation by

Deborah L. Carr; Audra N. Morse; John C. Zak; Todd A. Anderson

2011-01-01

341

On the Oxidative Degradation of Nadic End-Capped Polyimides. 3; Synthesis and Characterization of Model Compounds for End-Cap Degradation Products  

NASA Technical Reports Server (NTRS)

The oxidative degradation of PMR (for polymerization of monomeric reactants) polyimides at elevated temperatures was followed by cross-polarized magic angle spinning (CP-MAS) NMR. Labeling of selected sites in the polymers with C-13 allowed for direct observation of the transformations arising from oxidation processes. The formation of several degradation products has been proposed to be occurring in the cross-links derived from the nadic end caps on oxidation. Model compounds have been synthesized and characterized by CPMAS NMR with both normal and delayed decoupling to distinguish between protonated and unprotonated carbons. Comparison of these spectra to predicted chemical shifts of proposed products for the aged polymer provides further insight to degradation occurring in the cross-linked moieties.

Meador, Mary Ann B.; Johnston, J. Christopher; Frimer, Aryeh A.; Gilinsky-Sharon, Pessia

1999-01-01

342

Early diagenetic degradation products of bacteriohopanepolyols produced by Rhodopseudomonas palustris strain TIE-1  

NASA Astrophysics Data System (ADS)

The anoxygenic purple non-sulphur bacterium Rhodopseudomonas palustris strain TIE-1 has emerged as an excellent model organism to study hopanoid biosynthesis and function. It produces several C30 hopanoids, tetrahymanol, as well as various bacteriohopanepolyols (BHPs). In addition, TIE-1 is capable of methylating various hopanoids and the non-hopanoid pentacyclic terpenoid tetrahymanol at C-2, which is rare among hopanoid producers. Here, the lipid inventory of TIE-1 under anoxic photoautotrophic growth conditions using either H2 or Fe(II) as electron donor was studied. Adenosylhopane, aminotriol and bacteriohopanetetrol (BHT) were abundant when TIE-1 was grown on H2, but aminotriol and BHT were only found in traces when grown with Fe(II). Only during growth on Fe(II), BHT was found with and without C-2 methylation (25% of both BHT homologues), whereas the other BHPs were not C-2 methylated independent of growth mode. In C30 hopanoids and tetrahymanol, C-2 methylated compounds accounted for as much as 59% of the respective C-2 methylated/non-methylated homologues during growth with Fe(II), but only up to 24% during growth with H2. This observation reveals that C-2 methylated hopanoids may have a specific function in TIE-1 and are preferably synthesized in response to elevated Fe(II) concentrations. Further, we exposed the bacterial cells of strain TIE-1 to elevated temperatures and pressure aiming to produce early degradation products of bacteriohopanepolyols (BHPs). While so far, only few BHPs such as 32,35-anhydrobacteriohopanetetrol (anhydroBHT) have been identified as early diagenetic degradation products, in our experiments bacteriohopanetetrol (BHT) and possibly adenosylhopane were degraded to various anhydroBHT isomers, and new N-containing degradation products were discovered and tentatively assigned as anhydroaminotriols.

Eickhoff, Merle; Birgel, Daniel; Talbot, Helen M.; Peckmann, Jörn; Kappler, Andreas

2014-05-01

343

PESTICIDE ROOT ZONE MODEL (PRZM): A PROCEDURE FOR EVALUATING PESTICIDE LEACHING THREATS TO GROUNDWATER  

EPA Science Inventory

A continuous simulation model that considers interactions of pesticides in surface runoff (in water and on eroded sediment, advection in percolating water, molecular diffusion, dispersion, uptake by plants, sorption to soil, and biological and chemical degradation) is described. ...

344

Phosphorus, carbon- and nitrogen interactions in productive and degraded tropical pastures  

NASA Astrophysics Data System (ADS)

Pastures are the main land use in deforested areas of tropical South America. The highly weathered soils of these regions usually have low total and available phosphorus (P) contents. Low P availability can strongly limit plant and animal productivity and other soil ecosystem functions. Most introduced pastures of Brachiaria spp. are grass-alone (GA) while some are grass-legume (GL) pastures. The majority of the introduced pastures, particularly the grass-alone are at some state of degradation (GD). Pasture degradation induces severe loss of plant biomass production, with drastic ecological and economic implications. Although the importance of P deficiency in pasture degradation has been recognized, the knowledge generated on stoichiometry of carbon (C), nitrogen (N) and P along pathways of the nutrient cycles of pastures, with different botanical composition and productivity, has been very limited. We will present results of a case study realized during 2010 to 2011 in the forest margins agro-ecosystem of the department of Caquetá, Colombia. Our objectives were to determine: i) whether P availability is lower in degraded compared to productive pastures, and ii) whether the introduction of legumes in the pasture increases P availability through enhanced biological P cycling through plant growth, plant litter decomposition and the soil microbial biomass; and iii) whether pasture types (GA vs GL) and the state of pasture degradation affect the C:N:P ratios in nutrient pools of the soil-plant system. An on-farm study was conducted on nine farms in the department of Caquetá, Colombia. On every farm three different pasture types were studied: degraded grass alone pastures (GD), productive grass-alone pastures (GA) and productive grass-legume pastures (GL). Basic soil characteristics and indicators on soil P status, microbial P cycling, plant biomass production, plant litter deposition and nutrient concentrations in plant tissue were determined. Analysis of P, C and N in the microbial biomass, particulate organic matter and soil aggregates is in progress. Results showed that plant biomass production, litter deposition, soil organic P and basal soil respiration rate were significantly lower in GD than GA pastures. Moreover, clear trends towards lower total C, N, total P and microbial P per unit soil mass and higher Al saturation were observed in soils of GD compared to GA pastures while available soil P content and P concentration in plant biomass did not differ. No significant differences were found in any of the measured soil parameters between the two productive pasture types, GA and GL, but legume biomass has significantly higher N concentration and tends to have higher P concentration than grasses. 15-N natural abundance data indicated that legume N was largely derived from symbiotic N2 fixation. Biological P cycling was clearly reduced in GD compared to productive GA and GL pastures. This work highlights the importance of biological P cycling for developing sustainable pastoral systems and provides new knowledge on interactions of P with C and N.

Oberson, A.; Hegglin, D. D.; Nesper, M.; Rao, I.; Fonte, S.; Ramirez, B.; Velasquez, J.; Tamburini, F.; Bünemann, E. K.; Frossard, E.

2011-12-01

345

WPS REQUIREMENT TO PROVIDE BASIC PESTICIDE SAFETY INFORMATION TO UNTRAINED WORKERS  

E-print Network

WPS REQUIREMENT TO PROVIDE BASIC PESTICIDE SAFETY INFORMATION TO UNTRAINED WORKERS WHAT.S. Environmental Protection Agency. It covers pesticides that are used in the production of agricultural plants of pesticide-related illness and injury if you (1) use such pesticides, or (2) employ workers or pesticide

Pawlowski, Wojtek

346

77 FR 75152 - Notice of Receipt of Pesticide Products; Registration Applications  

Federal Register 2010, 2011, 2012, 2013

...at 5.25%. Product type: Plant Growth Regulator. Proposed use: Fruit color development/color enhancement on red apple varieties. Contact: Gina Burnett, BPPD, (703) 605-0513, email address: burnett.gina@epa.gov. List...

2012-12-19

347

77 FR 66836 - Notice of Receipt of Pesticide Products; Registration Applications  

Federal Register 2010, 2011, 2012, 2013

...Active ingredient: Biochemical Pheromone (Mating Disruptor) with Carob Moth Pheromone...90.8%. Product Type: Pheromone (Mating Disruptor). Proposed Uses: Manufacturing...Active ingredient: Biochemical Pheromone (Mating Disruptor) with Carob Moth...

2012-11-07

348

Products from the incomplete metabolism of pyrene by polycyclic aromatic hydrocarbon-degrading bacteria  

SciTech Connect

Pyrene is a regulated pollutant at sites contaminated with polycyclic aromatic hydrocarbons (PAH). It is mineralized by some bacteria but is also transformed to nonmineral products by a variety of other PAH-degrading bacteria. The authors examined the formation of such products by four bacterial strains and identified and further characterized the most apparently significant of these metabolites. Pseudomonas stutzeri strain P16 and Bacillus cereus strain P21 transformed pyrene primarily to cis-4,5-dihydro-4,5-dihydroxypyrene (PYRdHD), the first intermediate in the known pathway for aerobic bacterial mineralization of pyrene. Sphingomonas yanoikuyae strain R1 transformed pyrene to PYRdHD and pyrene-4,5-dione (PYRQ). Both strain R1 and Pseudomonas saccharophila strain P15 transform PYRdHD to PYRQ nearly stoichiometrically, suggesting that PYRQ is formed by oxidation of PYRdHD to 4,5-dihydroxypyrene and subsequent autoxidation of this metabolite. A pyrene-mineralizing organism, Mycobacterium strain PYR-1, also transforms PYRdHD to PYRQ at high initial concentrations of PYRdHD. However, strain PYR-1 is able to use both PYRdHD and PYRQ as growth substrates. PYRdHD strongly inhibited phenanthrene degradation by strains P15 and R1 but had only a minor effect on strains P16 and P21. At their aqueous saturation concentrations, both PYRdHD and PYRQ severely inhibited benzo[a]pyrene mineralization by strains P15 and R1. Collectively, these findings suggest that products derived from pyrene transformation have the potential to accumulate in PAH-contaminated systems and that such products can significantly influence the removal of other PAH. However, these products may be susceptible to subsequent degradation by organisms able to metabolize pyrene more extensively if such organisms are present in the system.

Kazunga, C.; Aitken, M.D.

2000-05-01

349

Bacterial degradation of chlorophenols and their derivatives.  

PubMed

Chlorophenols (CPs) and their derivatives are persistent environmental pollutants which are used in the manufacture of dyes, drugs, pesticides and other industrial products. CPs, which include monochlorophenols, polychlorophenols, chloronitrophenols, chloroaminophenols and chloromethylphenols, are highly toxic to living beings due to their carcinogenic, mutagenic and cytotoxic properties. Several physico-chemical and biological methods have been used for removal of CPs from the environment. Bacterial degradation has been considered a cost-effective and eco-friendly method of removing CPs from the environment. Several bacteria that use CPs as their sole carbon and energy sources have been isolated and characterized. Additionally, the metabolic pathways for degradation of CPs have been studied in bacteria and the genes and enzymes involved in the degradation of various CPs have been identified and characterized. This review describes the biochemical and genetic basis of the degradation of CPs and their derivatives. PMID:24589366

Arora, Pankaj Kumar; Bae, Hanhong

2014-01-01

350

Bacterial degradation of chlorophenols and their derivatives  

PubMed Central

Chlorophenols (CPs) and their derivatives are persistent environmental pollutants which are used in the manufacture of dyes, drugs, pesticides and other industrial products. CPs, which include monochlorophenols, polychlorophenols, chloronitrophenols, chloroaminophenols and chloromethylphenols, are highly toxic to living beings due to their carcinogenic, mutagenic and cytotoxic properties. Several physico-chemical and biological methods have been used for removal of CPs from the environment. Bacterial degradation has been considered a cost-effective and eco-friendly method of removing CPs from the environment. Several bacteria that use CPs as their sole carbon and energy sources have been isolated and characterized. Additionally, the metabolic pathways for degradation of CPs have been studied in bacteria and the genes and enzymes involved in the degradation of various CPs have been identified and characterized. This review describes the biochemical and genetic basis of the degradation of CPs and their derivatives. PMID:24589366

2014-01-01

351

HCH contamination from former pesticide production in Brazil--a challenge for the Stockholm Convention implementation.  

PubMed

Hexachlorocyclohexane (HCH) isomers (?-, ?- and ?- HCH [lindane]) were recently added to the list of persistent organic pollutants regulated by the Stockholm Convention, and therefore, the legacy of HCH and lindane production has become an issue of global relevance. The production of lindane with the much larger quantities of associated waste isomers has generated large waste deposits and contaminated sites. This article presents an overview of HCH-polluted sites in Brazil as a basis for further activities related to the Stockholm Convention. The locations of HCH stockpiles and contaminated sites in Brazil arising from production and formulation have been compiled and mapped. This shows that the measures taken over the past 25 years have not resulted in remediation of the HCH pollution. An exposure risk study has been summarised for one major site and is included to demonstrate the contemporary relevance of the contamination. Major site remediation efforts are planned at one site but people live close to several other sites, and there is an urgent need of further assessments and remediation to ensure the protection of human health and the environment. The Stockholm Convention requires a systematic approach and should be adopted for the assessment of all sites and appropriate isolation/remediation measures should be facilitated. The appropriate planning of these activities for the production site in Rio de Janeiro could be a positive contribution for Rio+20 highlighting that green economy and sustainable production also include the appropriate management of legacies of historic production of an industrial sector (here the organochlorine industry). PMID:22825640

Torres, J P M; Fróes-Asmus, C I R; Weber, R; Vijgen, J M H

2013-04-01

352

Pesticide and metabolite fate, release and transport modelling at catchment scale  

NASA Astrophysics Data System (ADS)

Pesticides are of great concern in hydrological catchments all over the world. On the one hand they are necessary to guarantee stable agricultural production for an increasing population. On the other hand they endanger life of aquatic animals and freshwater resources. However, not only pesticides but also their degradation products, the metabolites, are toxic to the environment, in some cases even more than the parent material. Thus, it is necessary to optimize pesticide application and management of agricultural land (e.g. grass strips, erosion prevention) with respect and according to their behaviour and degradation in hydrological catchments. Modelling provides a sound tool for assessing the impacts of pesticide management changes on pesticide behaviour at the field and in consecutively surface waters. Most of the various models available in literature do not consider metabolism. This study introduces an applicable integrated model assessing the fate and release of a pesticide and one metabolite at the field and in surface waters of a hydrological catchment. For the development of the field release model, the single-equation pesticide release formula by the OECD (2000) was used, which combines sorption and degradation in one equation. The part of the equation calculating the degradation forms the input of a second OECD equation representing the metabolite with its own parameters. A fraction can be specified describing how much of the degradation product is transferred to the specific metabolite. The river network is simulated with a further development of the MOHID River Network model (MRN). The integration of a pesticide type and a metabolite, with their degradation and volatilization processes are the main improvements of the hydrodynamic channel model. Following, the combined model was set up to the Israeli part of the Upper Jordan River basin, especially the Hula valley. According to the local hydrological conditions, a linear storage with a threshold was applied to 26 subbasins as a hydrological base for the OECD equation. Virtually, 1000 kg of Chlorpyrifos were applied to the basin in two doses per year. The metabolite chosen in this test-application was TCP. The results showed pesticide and metabolite concentrations in the river at the catchment outlet in the expected order of magnitude. Field pesticide followed the application as Dirac-impulse with a subsequent exponential decay and lowering by overland flow removal. TCP field amounts, however, are a combination of two exponential equations resulting in a delayed, smaller and smoothed peak. The river network model showed its ability to simulate transport, mixture and mitigation of the pesticides. The test run showed the applicability of the new model chain to asses pesticide and metabolite release to surface waters in catchment systems, but has to be validated by measurements of those components. It is expected to gain these validation measurements in late 2010 by the project DYKE.

Gaßmann, Matthias; Olsson, Oliver; Bauer, Melanie

2010-05-01

353

The use and disposal of household pesticides.  

PubMed

Most pesticides are synthetic chemicals manufactured specifically for their toxic properties to the target species, and widely used globally. Several epidemiological studies in the United States have suggested health concerns arising from the chronic exposure of young children to pesticides in the domestic environment. In the UK very little is currently known about how nonoccupational pesticides are being used or disposed of. Any use of pesticides is a potential risk factor for children's exposure, and any potential exposure is likely to be reduced by the parents' adopting precautionary behaviour when using these pesticide products. This was investigated using a sample of 147 parents from the Avon Longitudinal Study of Parents and Children cohort in and around Bristol, through an in-depth interview between August and November 2001. The results of this study add to the understanding of the underlying behaviour of parents applying pesticide products in the home environment in the UK. Pesticides are readily available, and are normally purchased in do-it-yourself shops and supermarkets and mostly disposed of in domestic waste. Safety was stated by 45% of parents to be the most important factor to consider when buying a pesticide. When buying pesticide products, labels were stated to be the most important source of information about pesticides. However, a third of parents stated they would not follow the product label exactly when using a product, just under half felt labels were both inadequate and hard to understand, and about 10% of parents would not take notice of warnings on the pesticide label. Less than half of parents would use gloves when applying a pesticide, although the use of protective equipment such as gloves during the application of pesticides could greatly reduce the exposure. It is a public health concern that the instructions on the labels of products may not always be understood or followed, and further understanding of user behaviour is needed. PMID:15476740

Grey, Charlotte N B; Nieuwenhuijsen, Mark J; Golding, Jean

2005-01-01

354

75 FR 34126 - Notice of Receipt of Requests to Voluntarily Cancel Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...FIFRA provides that a registrant of a pesticide product may at any time request that any of its pesticide registrations be canceled. FIFRA further...Administrator determines that continued use of the pesticide would pose an unreasonable adverse...

2010-06-16

355

75 FR 17716 - Notice of Receipt of Requests to Voluntarily Cancel Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...these registrations. Users of these pesticides or anyone else desiring the retention...FIFRA provides that a registrant of a pesticide product may at any time request that any of its pesticide registrations be canceled. FIFRA...

2010-04-07

356

77 FR 72343 - Notice of Receipt of Requests to Voluntarily Cancel Certain Pesticide Registrations  

Federal Register 2010, 2011, 2012, 2013

...advocates; the chemical industry; pesticide users; and members of the...distribution, or use of pesticides. B. What should I consider...from registrants to cancel 43 pesticide products registered under...Bee, Wasp & Hornet...

2012-12-05

357

77 FR 59190 - Halofenozide; Notice of Receipt of Requests To Voluntarily Cancel Pesticide Registrations and...  

Federal Register 2010, 2011, 2012, 2013

...Pesticide Registrations and Terminate All Uses AGENCY: Environmental Protection...voluntarily cancel pesticide registrations of all products containing the pesticide halofenozide. The requests would cancel all technical and end-use...

2012-09-26

358

Production of reference ``ancient'' Cu-based alloys and their accelerated degradation methods  

NASA Astrophysics Data System (ADS)

A large number of bronze artefacts found during archaeological excavations carried out in Italy in different contexts have been studied. Their chemical composition and metallurgical features have been determined by the combined use of different analytical surface and bulk techniques, such as optical microscopy (OM), scanning electron microscopy with energy dispersive X-ray micro-analysis (SEM-EDS), X-raydiffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The study of the corrosion products grown on the archaeological Cu-based artefacts and of their metallurgical features has revealed the quite ubiquitous and nearly constant presence of chlorine as the main corroding agent, and the different structures of the alloys. This information has been used to produce reference Cu-based alloys, whose chemical composition and micro-chemical structure is similar to that of the ancient alloys, and to propose the guidelines for carrying out the accelerated degradation tests to produce corroded samples for testing corrosion inhibiting products. The proposed tests were based on soil, chemical and (chemical+soil)-induced degradation, and the micro-chemical structure of the artificially produced corrosion layers has been compared to those grown on archaeological artefacts during burial. The comparison shows that the (chemical+soil)-induced degradation produces “patinas” that are similar to those grown on archaeological artefacts from a chemical, structural and micro-morphological point of view.

Casaletto, M. P.; de Caro, T.; Ingo, G. M.; Riccucci, C.

2006-06-01

359

Lignin degradation, ligninolytic enzymes activities and exopolysaccharide production by Grifola frondosa strains cultivated on oak sawdust  

PubMed Central

Fourteen strains of Grifola frondosa (Dicks.) S. F. Gray, originating from different regions (Asia, Europe and North America) were tested for lignin degradation, ligninolytic enzyme activities, protein accumulation and exopolysaccharide production during 55 days of cultivation on oak sawdust. Lignin degradation varied from 2.6 to7.1 % of dry weight of the oak sawdust substrate among tested strains. The loss of dry matter in all screened fungi varied between 11.7 and 33.0%, and the amount of crude protein in the dry substrate varied between 0.94 to 2.55%. The strain, MBFBL 596, had the highest laccase activity (703.3 U/l), and the maximum peroxidase activity of 22.6 U/l was shown by the strain MBFBL 684. Several tested strains (MBFBL 21, 638 and 662) appeared to be good producers of exopolysaccharides (3.5, 3.5 and 3.2 mg/ml respectively). PMID:24031728

Fernandes, Nona A.; Isikhuemhen, Omoanghe S.; Ohimain, Elijah I.

2011-01-01

360

77 FR 59611 - Notice of Receipt of Pesticide Products; Registration Applications  

Federal Register 2010, 2011, 2012, 2013

...Proposed Uses: To control Root Knot Nematodes on Cucurbits and Fruiting Vegetables...Pasteuria spp. (Hoplolaimus galeatus nematode)--Ph3 at 99.88%. Product Type...Pasteuria spp. (Hoplolaimus galeatus nematode)--Ph3 at 16.6450% and...

2012-09-28

361

78 FR 3422 - Notice of Receipt of Pesticide Products; Registration Applications  

Federal Register 2010, 2011, 2012, 2013

...P.O. Box 667, Ames, IA 50010. Active Ingredient: Trichoderma fertile strain JM41R at 96.0%. Product Type: Fungicide...P.O. Box 667, Ames, IA 50010. Active Ingredient: Trichoderma fertile strain JM41R at 7.7%. Proposed Use: For...

2013-01-16

362

A Review on the Fate of Pesticides during the Processes within the Food-Production Chain  

Microsoft Academic Search

Only the intake of toxicologically-significant amounts can lead to adverse health effects even for a relatively toxic substance. In the case of residues in foods this is based on two major aspects—first, how to determine quantitatively the presence of a pollutant in individual foods and diets, including its fate during the processes within the food production chain; and second, how

R. M. González-Rodríguez; R. Rial-Otero; B. Cancho-Grande; C. Gonzalez-Barreiro; J. Simal-Gándara

2011-01-01

363

Blockage of chloride channels and anion transporters with pesticidal natural products and their synthetic analogs  

Microsoft Academic Search

Ligand-gated chloride channels mediate a variety of functions in excitable membranes of nerve and muscle in insects, and have\\u000a a long history as targets for neurotoxic insecticides. Recent findings from our laboratory confirm that the natural product\\u000a silphinenes and their semi-synthetic analogs share a mode of action with the established ligand-gated chloride channel antagonist,\\u000a picrotoxinin. The silphinenes are non-selective, being

Dhana Raj Boina; Jeffrey R. Bloomquist

2011-01-01

364

Commercial opportunities for pesticides based on plant essential oils in agriculture, industry and consumer products  

Microsoft Academic Search

In spite of intensive research on plant natural products and insect-plant chemical interactions over the past three decades,\\u000a only two new types of botanical insecticides have been commercialized with any success in the past 15 years, those based on\\u000a neem seed extracts (azadirachtin), and those based on plant essential oils. Certain plant essential oils, obtained through\\u000a steam distillation and rich in

Murray B. Isman; Saber Miresmailli; Cristina Machial

2011-01-01

365

Poly(dimethylsiloxane) Microchip Electrophoresis with Contactless Conductivity Detection for Measurement of Chemical Warfare Agent Degradation Products  

Microsoft Academic Search

The applicability of a poly(dimethylsiloxane) (PDMS) microfluidic device with contactless conductivity detection for the determination of organophosphonate nerve agent degradation products is reported. Five alkyl methylphosphonic acids, isopropyl methylphosphonic acid (IMPA), pinacolyl methylphosphonic acid (PMPA), O?ethyl?N,N?dimethyl phosphoramidate (EDPA), ethyl methylphosphonic acid (EMPA), and methylphosphonic acid (MPA), (degradation products of Sarin, Soman, Tuban and VX nerve agents) were analyzed by microchip

Yongsheng Ding; Carlos D. Garcia; Kim R. Rogers

2008-01-01

366

Stability-Indicating Method for the Determination of Meloxicam and Tetracaine Hydrochloride in the Presence of their Degradation Products  

Microsoft Academic Search

Sensitive, spectrophotometric and densitometric methdos are described for the determination of meloxicam I and tetracaine hydrochloride II in the presence of their degradation products.Meloxicam was determined in the presence of its degradation products (5-methyl-2-aminothiazole) III and benzothiazine carboxylic acid IV by two methods. These methods are the first derivative Spectrophotometry at 338 nm and TLC densitometric method at 365nm. The

Lories I. Bebawy

1998-01-01

367

Health aspects of organophosphorous pesticides in asian countries.  

PubMed

Organophosphorous (OP) pesticides are used frequently in agriculture, particularly in Asian countries over the past decades. Poisoning by these agents, either as acute or chronic in these nations, is a serious health problem. OP pesticides residue in fruits and vegetables that may not induce early clinical features, could also affect the human health. Therefore, medical and health professionals should be aware and learn more on the toxicology, prevention and proper management of OP poisoning. The well-known mechanism of OP toxicity is the inhibition of acetyl cholinesterase, resulting in an accumulation of acetylcholine and continued stimulation of acetylcholine receptors. Therefore, they are also called anticholinesterase agents. Determination of blood acetyl cholinesterase and butyryl cholinesterase activities remains a mainstay for the rapid initial screening of OP pesticides. Quantitative analysis of OP and their degradation products in plasma and urine by mass spectrometric methods is a more specific method, but is expensive and limited to specialized laboratories. Therefore, history of OP pesticides exposure and clinical manifestations of a cholinergic syndrome is sufficient for management of the exposed patients. However, electrophysiological tests may be required for the diagnosis of delayed neuropathy of OP poisoning. The standard management of OP poisoning includes decontamination, atropine sulphate with an oxime. Recent advances focus on blood alkalinisation and magnesium sulphate as promising adjunctive therapies. Preventive measures in OP exposure are of great importance in human health in developing countries. Therefore, regulations and controls on safe use of OP particularly in Asian countries are recommended. PMID:23304659

Balali-Mood, M; Balali-Mood, K; Moodi, M; Balali-Mood, B

2012-01-01

368

Fate and transport of pesticides in the ground water systems of southwest Georgia, 1993-2005  

USGS Publications Warehouse

Modern agricultural practices in the United States have resulted in nearly unrivaled efficiency and productivity. Unfortunately, there is also the potential for release of these compounds to the environment and consequent adverse affects on wildlife and human populations. Since 1993, the National Water-Quality Assessment (NAWQA) program of the U.S. Geological Survey has evaluated water quality in agricultural areas to address these concerns. The objective of this study is to evaluate trends in pesticide concentrations from 1993-2005 in the surficial and Upper Floridan aquifers of southwest Georgia using pesticide and pesticide degradate data collected for the NAWQA program. There were six compounds - five herbicides and one degradate - that were detected in more than 20% of samples: atrazine, deethylatrazine (DEA), metolachlor, alachlor, floumeturon, and tebuthiuron. Of the 128 wells sampled during the study, only eight wells had pesticide concentrations that either increased (7) or decreased (1) on a decadal time scale. Most of the significant trends were increasing concentrations of pesticides in older water; median pesticide concentrations did not differ between the surficial and Upper Floridan aquifers from 1993 and 2005. Deethylatrazine, in the Upper Floridan aquifer, was the only compound that had a significant change (increase) in concentration during the study. The limited number of wells with increases in pesticide concentrations suggest that ground-water sources of these compounds are not increasing in concentration over the time scale represented in this study. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

Dalton, M.S.; Frick, E.A.

2008-01-01

369

Stress Degradation Behavior of Atorvastatin Calcium and Development of a Suitable Stability-Indicating LC Method for the Determination of Atorvastatin, its Related Impurities, and its Degradation Products.  

PubMed

A rapid, reversed-phase liquid chromatographic method was developed for the quantitative determination of Atorvastatin calcium, its related substances (12 impurities), and degradation impurities in bulk drugs. The chromatographic separation was achieved on a Zorbax Bonus-RP column by employing a gradient elution with water-acetonitrile-trifluoroacetic acid as the mobile phase in a shorter run time of 25 min. The flow rate was 1.0 mL/min and the detection wavelength was 245 nm. The drug substance was subjected to stress studies such as hydrolysis, oxidation, photolysis, and thermal degradation, and considerable degradation was observed in acidic hydrolysis, oxidative, thermal, and photolytic stress conditions. The formed degradation products were reported and were well-resolved from the Atorvastatin and its related substances. The stressed samples were quantified against a qualified reference standard and the mass balance was found to be close to 99.5% (w/w) when the response of the degradant was considered to be equal to the analyte (i.e. Atorvastatin), which demonstrates the stability-indicating capability of the method. The method was validated in agreement with ICH requirements. The method developed here was single and shorter (25 min method for the determination of all 12 related impurities of Atorvastatin and its degradation products), with clearly better resolution and higher sensitivity than the European (85 min method for the determination of six impurities) and United States pharmacopeia (115 min and 55 min, two different methods for the determination of six related substances). PMID:23641331

Vukkum, Pallavi; Moses Babu, J; Muralikrishna, R

2013-03-01

370

Analytical modeling of degradation product partitioning kinetics in source zones containing entrapped DNAPL  

NASA Astrophysics Data System (ADS)

Liquid-liquid equilibrium experiments indicate that there is a strong thermodynamic driving force for the reversible sequestration of cis-dichloroethene (DCE) within microbially active dense nonaqueous phase liquid (DNAPL) source zones containing chlorinated ethene solvents. Assessment of the importance of degradation product sequestration, however, requires accurate description of the mass transfer kinetics. Partitioning kinetics of cis-DCE were assessed in a series of transport experiments conducted in sandy columns containing uniformly entrapped tetrachloroethene (PCE)-nonaqueous phase liquids (NAPL). Effluent data from these experiments were simulated using an analytical solution adapted from the sorption literature. The solution permits interrogation of the relative importance of mass transfer resistance in the aqueous phase and NAPL. Column data and simulations suggest that the kinetic exchange of cis-DCE may be described with mass transfer correlations developed for the dissolution of pure component NAPLs. Diffusive transport within the entrapped ganglia was relatively fast, offering limited resistance to mass exchange. These results (1) establish the applicability of dissolution-based mass transfer correlations for modeling both absorption and dissolution of degradation products, (2) quantify the thermodynamic driving force for the partitioning of cis-DCE in PCE-NAPL by assessing the ternary phase behavior, and (3) guide incorporation and deployment of partitioning kinetics into multiphase compositional simulators when assessing or designing metabolic reductive dechlorination within DNAPL source zones. While focus is placed on examining degradation product partitioning in DNAPL source zones, results may also be useful when considering rate limitations in other liquid-liquid partitioning processes, such as partitioning tracer tests.

Ramsburg, C. Andrew; Christ, John A.; Douglas, Scott R.; Boroumand, Ali

2011-03-01

371

Stress Degradation Behavior of Abacavir Sulfate and Development of a Suitable Stability-Indicating UHPLC Method for the Determination of Abacavir, its Related Substances, and Degradation Products.  

PubMed

A novel, stability-indicating UHPLC method was developed for the quantitative determination of Abacavir sulfate, its related substances, and forced degradation impurities in bulk drugs. The chromatographic separation was achieved on a Waters Acquity BEH C(8), 50 mm × 2.1 mm, 1.7 ?m particle size column with a mobile containing a gradient mixture of solution A (0.10 % v/v o-phosphoric acid in water) and solution B (0.10% v/v o-phosphoric acid in methanol). The flow rate was set at 0.40 mL/min and the run time was 6.0 min. The drug substance was subjected to the stress studies of hydrolysis, oxidation, photolysis, and thermal degradation. Abacavir sulfate was found to degrade significantly under acidic hydrolysis and oxidative stress conditions. The formed degradation products were reported and were well-resolved from Abacavir and its related substances. The mass balance was found to be satisfactory in all of the stress conditions, thus proving the stability-indicating capability of the method. The developed UHPLC method was validated to be in agreement with ICH requirements and found to be rapid, accurate, precise, linear, specific, and suitable for the quantitative determination of related substances and degradants in the bulk drug samples of Abacavir sulfate. PMID:23264939

Vukkum, Pallavi; Deshpande, Girish R; Babu, J Moses; Muralikrishna, R; Jagu, Pavani

2012-12-01

372

EDS and ?-XRF mapping of amalgam degradation products in ancient mirrors.  

PubMed

An amalgam mirror is a mirror type, used from the fifteenth century until the end of the nineteenth century, where the reflective layer is constituted by a tin amalgam layer adhered to a glass sheet. In this work, two amalgam mirrors samples were studied by scanning electron microscopy with an energy dispersive spectrometer and by micro-X-ray fluorescence elemental mapping to go deeply into the understanding of the degradation mechanism of the amalgam layer of ancient mirrors. The investigation has been focused for the first time on the reflective surface of the amalgam layer adherent to the glass sheet to better understand the processes of amalgam corrosion. The two amalgam degradation compounds, romarchite and cassiterite, has been spatially differentiated by scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) maps. SEM images and micro-X-ray fluorescence and EDS maps showed that the amalgam degradation products grow up to form hemispherical stratified calottes. This structure is probably due to a mechanism involves cyclic phases and oxygen radial diffusion from a superficial oxidation nucleus. PMID:24420559

Arizio, E; Orsega, E F; Falcone, R; Vallotto, M

2014-12-01

373

Characterization of intermediate products of solar photocatalytic degradation of ranitidine at pilot-scale.  

PubMed

In the present study the mechanisms of solar photodegradation of H(2)-receptor antagonist ranitidine (RNTD) were studied in a well-defined system of a pilot plant scale Compound Parabolic Collector (CPC) reactor. Two types of heterogeneous photocatalytic experiments were performed: catalysed by titanium-dioxide (TiO(2)) semiconductor and by Fenton reagent (Fe(2+)/H(2)O(2)), each one with distilled water and synthetic wastewater effluent matrix. Complete disappearance of the parent compounds and discreet mineralization were attained in all experiments. Furthermore, kinetic parameters, main intermediate products, release of heteroatoms and formation of carboxylic acids are discussed. The main intermediate products of photocatalytic degradation of RNTD have been structurally elucidated by tandem mass spectrometry (MS(2)) experiments performed at quadrupole-time of flight (QqToF) mass analyzer coupled to ultra-performance liquid chromatograph (UPLC). RNTD displayed high reactivity towards OH radicals, although a product of conduction band electrons reduction was also present in the experiment with TiO(2). In the absence of standards, quantification of intermediates was not possible and only qualitative profiles of their evolution could be determined. The proposed TiO(2) and photo-Fenton degradation routes of RNTD are reported for the first time. PMID:20207392

Radjenovi?, Jelena; Sirtori, Carla; Petrovi?, Mira; Barceló, Damiŕ; Malato, Sixto

2010-04-01

374

Optimization of protein production by Micrococcus luteus for exploring pollutant-degrading uncultured bacteria.  

PubMed

The screening of pollutant-degrading bacteria are limited due to most of bacteria in the natural environment cannot be cultivated. For the purpose of resuscitating and stimulating "viable but non-culturable" (VBNC) or uncultured bacteria, Micrococcus luteus proteins are more convenient and cost-effective than purified resuscitation-promoting factor (Rpf) protein. In this study, medium composition and culture conditions were optimized by using statistical experimental design and analysis to enhance protein production by M. luteus. The most important variables influencing protein production were determined using the Plackett-Burman design (PBD) and then central composite design (CCD) was adopted to optimize medium composition and culture conditions to achieve maximum protein yield. Results showed that the maximum protein yield of 25.13 mg/L (vs. 25.66 mg/L predicted) was obtained when the mineral solution, Lithium L-lactate, initial pH and incubation time were set at 1.5 ml/L, 8.75 g/L, 7.5 and 48 h, respectively. The predicated values calculated with the model were very close to the experimental values. Protein production was obviously increased with optimization fitting well with the observed fluorescence intensity. These results verified the feasibility and accuracy of this optimization strategy. This study provides promising information for exploring highly desirable pollutant-degrading microorganisms. PMID:24616844

Su, Xiaomei; Liu, Yindong; Hu, Jinxing; Ding, Linxian; Shen, Chaofeng

2014-01-01

375

LC/MS/MS identification of some folic acid degradation products after E-beam irradiation  

NASA Astrophysics Data System (ADS)

Folates belong to the B vitamin group based on the parental compound folic acid (FA). They are involved in important biochemical processes like DNA synthesis and repair. FA is composed of a pteridine ring, p-aminobenzoic acid and glutamate moieties. The human metabolism is not able to synthesize folates and therefore obtain them from diet. FA, a synthetic vitamin, is used as a food fortificant because of its low price, relative stability and increased bioavailability compared to natural folate forms. FA is known to be a sensitive compound easily degradable in aqueous solution by ultraviolet and visible light towards various by-products. Irradiation is a process for preservation of foods that uses accelerated electrons, gamma rays or X-rays. Irradiation is proposed for the treatment of various food products, eliminating or reducing pathogens and insects, increasing the storage time and replacing chemical fumigants. This study concerns the identification of degradation products of FA after E-beam irradiation. FA aqueous solutions were irradiated with a Van de Graaff electrons beam accelerator (2 MeV, 100 ?A current, 20 cm scan width, dose rate about 2 kGy/s). Applied doses were between 0 (control) and 10.0 kGy. Absorbed doses were monitored with FWT 60.00 radiochromic dosimeters.

Araújo, M. M.; Marchioni, E.; Zhao, M.; Kuntz, F.; Di Pascoli, T.; Villavicencio, A. L. C. H.; Bergaentzle, M.

2012-08-01

376

Separation of ibuprofen, codeine phosphate, their degradation products and impurities by capillary electrophoresis. II. Validation.  

PubMed

A micellar electrokinetic chromatography method for the determination of ibuprofen and codeine phosphate hemihydrate and their degradation products and impurities in a commercial tablet formulation has been validated. The validation has been performed according to the International Conference of Harmonisation's guidance on the validation of analytical methods, and selectivity, linearity, accuracy, precision, detection limit, quantitation limit, robustness and range test were performed to determine the suitability of the method. It was possible to use the fractional factorial design model from the optimisation of the method to draw conclusions about its robustness. The results confirm that the method is highly suitable for its intended purpose. PMID:9882139

Stubberud, K P; Aström, O

1998-11-20

377

A comparison of organophosphate degradation genes and bioremediation applications.  

PubMed

Organophosphates (OPs) form the bulk of pesticides that are currently in use around the world accounting for more than 30% of the world market. They also form the core for many nerve-based warfare agents including sarin and soman. The widespread use and the resultant build-up of OP pesticides and chemical nerve agents has led to the development of major health problems due to their extremely toxic interaction with any biological system that encounters them. Growing concern over the accumulation of OP compounds in our food products, in the soils from which they are harvested and in wastewater run-off has fuelled a growing interest in microbial biotechnology that provides cheap, efficient OP detoxification to supplement expensive chemical methods. In this article, we review the current state of knowledge of OP pesticide and chemical agent degradation and attempt to clarify confusion over identification and nomenclature of two major families of OP-degrading enzymes through a comparison of their structure and function. The isolation, characterization, utilization and manipulation of the major detoxifying enzymes and the molecular basis of degradation of OP pesticides and chemical nerve agents are discussed as well as the achievements and technological advancements made towards the bioremediation of such compounds. PMID:24249287

Iyer, Rupa; Iken, Brian; Damania, Ashish

2013-12-01

378

Protocol for an electrospray ionization tandem mass spectral product ion library: development and application for identification of 240 pesticides in foods.  

PubMed

Modern determination techniques for pesticides must yield identification quickly with high confidence for timely enforcement of tolerances. A protocol for the collection of liquid chromatography (LC) electrospray ionization (ESI)-quadruple linear ion trap (Q-LIT) mass spectrometry (MS) library spectra was developed. Following the protocol, an enhanced product ion (EPI) library of 240 pesticides was developed by use of spectra collected from two laboratories. A LC-Q-LIT-MS workflow using scheduled multiple reaction monitoring (sMRM) survey scan, information-dependent acquisition (IDA) triggered collection of EPI spectra, and library search was developed and tested to identify the 240 target pesticides in one single LC-Q-LIT MS analysis. By use of LC retention time, one sMRM survey scan transition, and a library search, 75-87% of the 240 pesticides were identified in a single LC/MS analysis at fortified concentrations of 10 ng/g in 18 different foods. A conventional approach with LC-MS/MS using two MRM transitions produced the same identifications and comparable quantitative results with the same incurred foods as the LC-Q-LIT using EPI library search, finding 1.2-49 ng/g of either carbaryl, carbendazim, fenbuconazole, propiconazole, or pyridaben in peaches; carbendazim, imazalil, terbutryn, and thiabendazole in oranges; terbutryn in salmon; and azoxystrobin in ginseng. Incurred broccoli, cabbage, and kale were screened with the same EPI library using three LC-Q-LIT and a LC-quadruple time-of-flight (Q-TOF) instruments. The library search identified azoxystrobin, cyprodinil, fludioxinil, imidacloprid, metalaxyl, spinosyn A, D, and J, amd spirotetramat with each instrument. The approach has a broad application in LC-MS/MS type targeted screening in food analysis. PMID:22686274

Zhang, Kai; Wong, Jon W; Yang, Paul; Hayward, Douglas G; Sakuma, Takeo; Zou, Yunyun; Schreiber, André; Borton, Christopher; Nguyen, Tung-Vi; Kaushik, Banerjee; Oulkar, Dasharath

2012-07-01

379

Environmental impacts from pesticide use: a case study of soil fumigation in Florida tomato production.  

PubMed

The search for alternative fumigants has been ongoing since the 1992 Parties of the Montreal Protocol classified methyl bromide as a Class I controlled substance with an ozone depletion potential (ODP) of 0.7 and destined it for phase-out. This paper focuses on the hazards from fumigants proposed as alternatives for pre-plant soil fumigation in tomato production. We use the Environmental Impact Quotient (EIQ) developed by Kovach et al. to estimate the hazards from methyl bromide and the proposed alternative fumigants to workers, consumers, beneficial arthropods, birds, fish, and bees. Our findings indicate that iodomethane 98/2 has the lowest EIQ index value and field use rating, and is the alternative with the lowest relative risk. Among environmental categories, workers and beneficial arthropods experience the highest relative risks from the proposed tomato fumigants, and fish and consumers the least risks. PMID:22408594

Sande, Doris; Mullen, Jeffrey; Wetzstein, Michael; Houston, Jack

2011-12-01

380

America's Growing Dilemma: Pesticides in Food and Water.  

ERIC Educational Resources Information Center

Public concern about the safety of continued reliance on pesticides in agricultural production is widespread and growing. The lack of understanding of how food is grown, the role of pesticides in food production, the risk assessment and regulatory processes and alternatives to pesticide use limits citizen participation in food safety debates and…

Strauss, Valerie; Sullivan, Monica, Ed.

381

PERMEATION RESISTANCE OF GLOVE MATERIALS TO AGRICULTURAL PESTICIDES  

EPA Science Inventory

The toxicities of many agricultural pesticides require that hand protection be provided to persons who mix, load, and apply these products. he selection of appropriate handwear is particularly problematic for pesticides that contain organic solvents or active ingredients that beh...

382

X-ray photoelectron spectroscopy characterization of composite TiO 2-poly(vinylidenefluoride) films synthesised for applications in pesticide photocatalytic degradation  

NASA Astrophysics Data System (ADS)

X-ray photoelectron spectroscopy (XPS) was adopted for the analytical characterization of composite titanium dioxide-poly(vinylidenefluoride) (TiO 2-PVDF) films developed for applications in the photocatalytic degradation of pollutants. The composites were deposited on glass substrates by casting or spin coating from TiO 2-PVDF suspensions in dimethylformamide (DMF). XPS data on the TiO 2-PVDF surface composition were used to optimize preparation conditions (composition of the TiO 2/PVDF suspension, deposition technique) in terms of titanium dioxide surface amount and film stability. The use of spin-coating deposition and the increase of TiO 2 amount in the DMF suspensions were found to improve the titanium surface content, although high TiO 2/PVDF ratios led to film instability. PVDF-TiO 2 films were also used in preliminary photocatalytic degradation tests on isoproturon, a phenylurea herbicide, under solar UV irradiation; the results were compared to direct photolysis to evaluate the catalytic efficiency of immobilized TiO 2 and the role played by the PVDF film during the degradation process.

Losito, I.; Amorisco, A.; Palmisano, F.; Zambonin, P. G.

2005-02-01

383

Pesticide application practices, pest knowledge, and cost-benefits of plantain production in the Bribri-Cabecar Indigenous Territories, Costa Rica  

SciTech Connect

The use of pesticides in the cultivation of cash crops such as banana and plantain is increasing, in Costa Rica and worldwide. Agrochemical use and occupational and environmental exposures in export banana production have been documented in some parts of Central America. However, the extent of agrochemical use, agricultural pest knowledge, and economic components in plantain production are largely unknown in Costa Rica, especially in remote, high-poverty areas such as the Bribri-Cabecar Indigenous Territories. Our objective was to integrate a rapid rural appraisal of indigenous farmer pesticide application practices and pest knowledge with a cost-benefit analysis of plantain production in the Bribri-Cabecar Indigenous Territories, for the development of better agricultural management practices and improved regulatory infrastructure. Interviews conducted with 75 households in 5 indigenous communities showed that over 60% of participants grew plantain with agrochemicals. Of these plantain farmers, over 97% used the insecticide chlorpyrifos, and 84% applied nematicides, 64% herbicides, and 22% fungicides, with only 31% of participants reporting the use of some type of protective clothing during application. The banana weevil (Cosmopolites sordidus Germar) was ranked as the most important agricultural pest by 85% of participants, yet only 28% could associate the adult and larval form. A cost-benefit analysis conducted with a separate group of 26 plantain farmers identified several national markets and one export market for plantain production in the Indigenous Territories. Yearly income averaged US$6200/ha and yearly expenses averaged US$1872/ha, with an average cost-benefit ratio of 3.67 for plantain farmers. Farmers applied an average of 9.7 kg a.i./ha/yr of pesticide products and 375 kg/ha/yr of fertilizer, but those who sold their fruit to the national markets applied more nematicides, herbicides, and fertilizers than those who sold primarily to export markets, suggesting a lack of appropriate application knowledge. Results indicate that the quantity of agrochemicals applied in plantain cultivation is less than that applied in export banana, but the absence of appropriate agrochemical application practices in plantain cultivation may pose serious risks to human and environmental health. Culturally appropriate farmer education and certification programs are needed as well as the development of safe-handling practices, regulatory infrastructure, and adequate agrochemical storage, transport, and waste disposal facilities. Long-term solutions however, are dependent on the development of policies and infrastructure that support non-chemical pest management, alternatives to pesticides, and the identification of organic plantain markets.

Polidoro, Beth A. [Department of Plant, Soil and Entomological Sciences, University of Idaho, P.O. Box 442339, Moscow, ID 83844-2339 (United States); Department of Agroforestry, Tropical Agricultural Research and Higher Education Center (CATIE), Turrialba (Costa Rica)], E-mail: bethpolidoro@vandals.uidaho.edu; Dahlquist, Ruth M. [Department of Plant, Soil and Entomological Sciences, University of Idaho, P.O. Box 442339, Moscow, ID 83844-2339 (United States); Department of Agroforestry, Tropical Agricultural Research and Higher Education Center (CATIE), Turrialba (Costa Rica); Castillo, Luisa E. [Central American Institute for Studies on Toxic Substances (IRET), Universidad Nacional, Heredia (Costa Rica); Morra, Matthew J. [Department of Plant, Soil and Entomological Sciences, University of Idaho, P.O. Box 442339, Moscow, ID 83844-2339 (United States); Somarriba, Eduardo [Department of Agroforestry, Tropical Agricultural Research and Higher Education Center (CATIE), Turrialba (Costa Rica); Bosque-Perez, Nilsa A. [Department of Plant, Soil and Entomological Sciences, University of Idaho, P.O. Box 442339, Moscow, ID 83844-2339 (United States)

2008-09-15

384

Degradation of three aromatic dyes by white rot fungi and the production of ligninolytic enzymes.  

PubMed

This study was conducted to evaluate the degradation of aromatic dyes and the production of ligninolytic enzymes by 10 white rot fungi. The results of this study revealed that Pycnoporus cinnabarinus, Pleurotus pulmonarius, Ganoderma lucidum, Trametes suaveolens, Stereum ostrea and Fomes fomentarius have the ability to efficiently degrade congo red on solid media. However, malachite green inhibited the mycelial growth of these organisms. Therefore, they did not effectively decolorize malachite green on solid media. However, P. cinnabarinus and P. pulmonarius were able to effectively decolorize malachite green on solid media. T. suaveolens and F. rosea decolorized methylene blue more effectively than any of the other fungi evaluated in this study. In liquid culture, G. lucidum, P. cinnabarinus, Naematoloma fasciculare and Pycnoporus coccineus were found to have a greater ability to decolorize congo red. In addition, P. cinnabarinus, G. lucidum and T. suaveolens decolorized methylene blue in liquid media more effectively than any of the other organisms evaluated in this study. Only F. fomentarius was able to decolorize malachite green in liquid media, and its ability to do so was limited. To investigate the production of ligninolytic enzymes in media containing aromatic compounds, fungi were cultured in naphthalene supplemented liquid media. P. coccineus, Coriolus versicolor and P. cinnabarinus were found to produce a large amount of laccase when grown in medium that contained napthalene. PMID:23990745

Jayasinghe, Chandana; Imtiaj, Ahmed; Lee, Geon Woo; Im, Kyung Hoan; Hur, Hyun; Lee, Min Woong; Yang, Hee-Sun; Lee, Tae-Soo

2008-06-01

385

Effect of chlorine dioxide on cyanobacterial cell integrity, toxin degradation and disinfection by-product formation.  

PubMed

Bench scale tests were conducted to study the effect of chlorine dioxide (ClO2) oxidation on cell integrity, toxin degradation and disinfection by-product formation of Microcystis aeruginosa. The simulated cyanobacterial suspension was prepared at a concentration of 1.0×10(6)cells/mL and the cell integrity was measured with flow cytometry. Results indicated that ClO2 can inhibit the photosynthetic capacity of M. aeruginosa cells and almost no integral cells were left after oxidation at a ClO2 dose of 1.0mg/L. The total toxin was degraded more rapidly with the ClO2 dosage increasing from 0.1mg/L to 1.0mg/L. Moreover, the damage on cell structure after oxidation resulted in released intracellular organic matter, which contributed to the formation of trihalomethanes (THMs) and haloacetic acids (HAAs) as disinfection by-products. Therefore, the use of ClO2 as an oxidant for treating algal-rich water should be carefully considered. PMID:24651056

Zhou, Shiqing; Shao, Yisheng; Gao, Naiyun; Li, Lei; Deng, Jing; Zhu, Mingqiu; Zhu, Shumin

2014-06-01

386

Hydroxyl radical-induced degradation of fenuron in pulse and gamma radiolysis: kinetics and product analysis.  

PubMed

Radiolytic reactions of phenylureas were studied in detail with fenuron model compound in dilute aqueous solutions using pulse radiolysis for detection of the intermediates, gamma radiolysis with UV-Vis and HPLC-MS techniques for analysis of the final products. The kinetics of oxidation was followed by COD, TOC and toxicity measurements. During radiolysis of aerated solutions hydroxyl radical ((•)OH), eaq (-), H(•) and O2 (•-)/HO2 (•) reactive intermediates are produced, the degradation of solute takes place practically entirely through (•)OH reactions. Therefore, the product distribution is similar to the distributions reported in other advanced oxidation processes with (•)OH as main reactant. (•)OH mainly reacts with the aromatic ring, forming cyclohexadienyl radical as an intermediate. This radical in pulse radiolysis has a wide absorption band in the 310-390 nm wavelength range with a maximum at 350 nm. Cyclohexadienyl radical reacts with dissolved O2 with a rate coefficient of ?4?×?10(8) mol(-1) dm(3) s(-1) forming peroxy radical. The latter may eliminate HO2 (•) giving phenols or undergoes fragmentation. The one-electron oxidant (•)OH on average induces more than two-electron oxidations. The toxicity first increases with absorbed dose, then decreases. This increase is partly due to phenols formed during the first degradation period. PMID:24965004

Kovács, Krisztina; Mile, Viktoria; Csay, Tamás; Takács, Erzsébet; Wojnárovits, László

2014-11-01

387

Keratinase production and keratin degradation by a mutant strain of Bacillus subtilis *  

PubMed Central

A new feather-degrading bacterium was isolated from a local feather waste site and identified as Bacillus subtilis based on morphological, physiochemical, and phylogenetic characteristics. Screening for mutants with elevated keratinolytic activity using N-methyl-N?-nitro-N-nitrosoguanidine mutagenesis resulted in a mutant strain KD-N2 producing keratinolytic activity about 2.5 times that of the wild-type strain. The mutant strain produced inducible keratinase in different substrates of feathers, hair, wool and silk under submerged cultivation. Scanning electron microscopy studies showed the degradation of feathers, hair and silk by the keratinase. The optimal conditions for keratinase production include initial pH of 7.5, inoculum size of 2% (v/v), age of inoculum of 16 h, and cultivation at 23 °C. The maximum keratinolytic activity of KD-N2 was achieved after 30 h. Essential amino acids like threonine, valine, methionine as well as ammonia were produced when feathers were used as substrates. Strain KD-N2, therefore, shows great promise of finding potential applications in keratin hydrolysis and keratinase production. PMID:18196614

Cai, Cheng-gang; Lou, Bing-gan; Zheng, Xiao-dong

2008-01-01

388

Continuous flow stable isotope methods for study of ??13C fractionation during halomethane production and degradation  

USGS Publications Warehouse

Gas chromatography/mass spectrometry/isotope ratio mass spectrometry (GC/MS/IRMS) methods for ??13C measurement of the halomethanes CH3Cl, CH3Br, CH3I and methanethiol (CH3SH) during studies of their biological production, biological degradation, and abiotic reactions are presented. Optimisation of gas chromatographic parameters allowed the identification and quantification of CO2, O2, CH3Cl, CH3Br, CH3I and CH3SH from a single sample, and also the concurrent measurement of ??13C for each of the halomethanes and methanethiol. Precision of ??13C measurements for halomethane standards decreased (??0.3, ??0.5 and ??1.3%???) with increasing mass (CH3Cl, CH3Br, CH3I, respectively). Given that carbon isotope effects during biological production, biological degradation and some chemical (abiotic) reactions can be as much as 100???, stable isotope analysis offers a precise method to study the global sources and sinks of these halogenated compounds that are of considerable importance to our understanding of stratospheric ozone destruction. ?? 2001 John Wiley & Sons, Ltd.

Kalin, R.M.; Hamilton, J.T.G.; Harper, D.B.; Miller, L.G.; Lamb, C.; Kennedy, J.T.; Downey, A.; McCauley, S.; Goldstein, A.H.

2001-01-01

389

Production of keratinolytic enzyme by an indigenous feather-degrading strain Bacillus cereus Wu2.  

PubMed

A novel feather-degrading microorganism was isolated from a poultry farm in Taiwan, and was identified Bacillus cereus Wu2 according to 16S rRNA sequencing. The isolated strain produces keratinolytic enzyme using chicken feather as the sole carbon and nitrogen source. The experimental results indicated that the extra carbon sources (glucose, fructose, starch, sucrose, or lactose) could act as a catabolite repressor to the enzyme secretion or keratinolytic activity when keratinous substrates were employed as protein sources. However, addition of 2 g/L of NH(4)Cl to the feather medium increased the enzyme production. The optimum temperature and initial pH for enzyme production were 30°C and 7.0, respectively. The maximum yield of the enzyme was 1.75 kU/mL in the optimal chicken feather medium; this value was about 17-fold higher than the yield in the basal hair medium. The B. cereus Wu2 possessed disulfide reductase activity along with keratinolytic activity. The amino acid contents of feathers degradated by B. cereus Wu2 were higher, especially for lysine, methionine and threonine which were nutritionally essential amino acids and usually deficient in the feather meal. Thus, B. cereus Wu2 could be not only used to enhance the nutritional value of feather meal but is also a potential bioinoculant in agricultural environments. PMID:22999356

Lo, Wei-Hsun; Too, Jui-Rze; Wu, Jane-Yii

2012-12-01

390

Antibacterial Activity within Degradation Products of Biological Scaffolds Composed of Extracellular Matrix  

PubMed Central

Biological scaffolds composed of extracellular matrix (ECM) have been shown to be resistant to deliberate bacterial contamination in preclinical in vivo studies. The present study evaluated the degradation products resulting from the acid digestion of ECM scaffolds for antibacterial effects against clinical strains of Staphylococcus aureus and Escherichia coli. The ECM scaffolds were derived from porcine urinary bladder (UBM-ECM) and liver (L-ECM). These biological scaffolds were digested with acid at high temperatures, fractionated using ammonium sulfate precipitation, and tested for antibacterial activity in a standardized in vitro assay. Degradation products from both UBM-ECM and L-ECM demonstrated antibacterial activity against both S. aureus and E. coli. Specific ammonium sulfate fractions that showed antimicrobial activity varied for the 2 different ECM scaffold types. The results of this study suggest that several different low-molecular-weight peptides with antibacterial activity exist within ECM and that these peptides may help explain the resistance to bacterial infection provided by such biological scaffolds. PMID:17518662

BRENNAN, ELLEN P.; REING, JANET; CHEW, DOUGLAS; MYERS-IRVIN, JULIE M.; YOUNG, E.J.; BADYLAK, STEPHEN F.

2011-01-01

391

Antibacterial activity within degradation products of biological scaffolds composed of extracellular matrix.  

PubMed

Biological scaffolds composed of extracellular matrix (ECM) have been shown to be resistant to deliberate bacterial contamination in preclinical in vivo studies. The present study evaluated the degradation products resulting from the acid digestion of ECM scaffolds for antibacterial effects against clinical strains of Staphylococcus aureus and Escherichia coli. The ECM scaffolds were derived from porcine urinary bladder (UBM-ECM) and liver (L-ECM). These biological scaffolds were digested with acid at high temperatures, fractionated using ammonium sulfate precipitation, and tested for antibacterial activity in a standardized in vitro assay. Degradation products from both UBM-ECM and L-ECM demonstrated antibacterial activity against both S. aureus and E. coli. Specific ammonium sulfate fractions that showed antimicrobial activity varied for the 2 different ECM scaffold types. The results of this study suggest that several different low-molecular-weight peptides with antibacterial activity exist within ECM and that these peptides may help explain the resistance to bacterial infection provided by such biological scaffolds. PMID:17518662

Brennan, Ellen P; Reing, Janet; Chew, Douglas; Myers-Irvin, Julie M; Young, E J; Badylak, Stephen F

2006-10-01

392

Development of an LCMS\\/MS method for the determination of pesticides and patulin in apples  

Microsoft Academic Search

A method for the simultaneous determination of 33 pesticides or degradation products together with patulin in apples by liquid chromatography-tandem mass spectrometry (LC-MS\\/MS) was developed. The method involved homogenization of the apples, extraction with ammonium acetate–acetic acid solution in methanol–water by ultrasonication, filtration, and determination by LC-MS\\/MS. The repeatability and within-laboratory reproducibility for the three spiking levels 0.02, 0.04 and

H. B. Christensen; M. E. Poulsen; P. H. Rasmussen; D. Christen

2009-01-01

393

Organochlorine pesticides, polychlorinated biphenyls, and mercury in osprey eggs — 1970–79 — and their relationships to shell thinning and productivity  

Microsoft Academic Search

Osprey (Pandion haliaetus) eggs were collected in 14 states in 1970–79 and analyzed for organochlorine pesticides, polychlorinated biphenyls (PCBs), and mercury. Moderate shell thinning occurred in eggs from several areas. DDE was detected in all eggs, PCBs in 99%, DDD in 96%, dieldrin in 52%, and other compounds less frequently. Concentrations of DDT and its metabolites declined in eggs from

Stanley N. Wiemeyer; Christine M. Bunck; Alexander J. Krynitsky

1988-01-01

394

Globalization, Foreign Investment Dependence and Agriculture Production: Pesticide and Fertilizer Use in Less-Developed Countries, 1990-2000  

ERIC Educational Resources Information Center

Bridging the areas of political-economic sociology, the sociology of agriculture and environmental sociology, this study tests two hypotheses derived from a refined theory of foreign investment dependence. The hypotheses state that pesticide and fertilizer use intensity in less-developed countries are both positively associated with foreign…

Jorgenson, Andrew K.; Kuykendall, Kennon A.

2008-01-01

395

Culture media statistical optimization for biomass production of a ligninolytic fungus for future rice straw degradation.  

PubMed

The main objective of this study was to optimize a culture media for low scale biomass production of Pleurotus spp. Future applications of this optimization will be implemented for "in situ" rice straw degradation, increase soil nutrients availability, and lower residue and rice culture management costs. Soil samples were taken from different points in six important rice production cities in Colombia. For carbon and nitrogen source selection a factorial 4(2) design was carried out. The Plackett-Burman design permitted to detect carbon, nitrogen and inducer effects on fungus growth (response variable for all designs). This optimization was carried out by a Box-Behnken design. Finally a re-optimization assay for glucose concentration was performed by means of a One Factor design. Only 4/33 (12 %) isolates showed and important laccase or manganese peroxidase activity compared to Pleurotus ostreatus (HPB/P3). We obtained an increased biomass production in Pleurotus spp. (T1.1.) with glucose, followed by rice husk. Rice straw was considered an inducing agent for lignin degradation. Glucose was a significant component with positive effects, whereas Tween 80 and pH had negative effects. On the contrary, rice husk, yeast extract and CaCl2 were not significant components for increase the biomass production. Final media composition consisted of glucose 25 g L(-1), yeast extract 5 g L(-1), Tween 80 0.38 % (v/v), Rice husk 10 g L(-1), CaCl2 1 g L(-1), and pH 4.88 ± 0.2. The Box-Behnken polynomial prediction resulted to be lower than the experimental validation of the model (6.59 vs. 6.91 Log10 CFU ml(-1) respectively). PMID:24426109

Sarria-Alfonso, Viviana; Sánchez-Sierra, John; Aguirre-Morales, Mauricio; Gutiérrez-Rojas, Ivonne; Moreno-Sarmiento, Nubia; Poutou-Pińales, Raúl A

2013-06-01

396

Accurate quantitation of pentaerythritol tetranitrate and its degradation products using liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry.  

PubMed

After an explosion of pentaerythritol tetranitrate (PETN), its degradation products pentaerythritol trinitrate (PETriN), dinitrate (PEDiN) and mononitrate (PEMN) were detected using liquid chromatography-atmospheric-pressure chemical-ionization-mass spectrometry (LC-APCI-MS). Discrimination between post-explosion and naturally degraded PETN could be achieved based on the relative amounts of the degradation products. This information can be used as evidence when investigating a possible relationship between a suspect and a post-explosion crime scene. The present work focuses on accurate quantitation of PETN and its degradation products, using PETriN, PEDiN and PEMN standards specifically synthesized for this purpose. With the use of these standards, the ionization behavior of these compounds was studied, and a quantitative method was developed. Quantitation of PETN and trace levels of its degradation products was shown to be possible with accuracy between 85.7% and 103.7% and a precision ranging from 1.3% to 11.5%. The custom-made standards resulted in a more robust and reliable method to discriminate between post-explosion and naturally-degraded PETN. PMID:24656542

Brust, Hanneke; van Asten, Arian; Koeberg, Mattijs; Dalmolen, Jan; van der Heijden, Antoine; Schoenmakers, Peter

2014-04-18

397

Production and Characterization of Polymeric Lignin Degradation Intermediates from Two Different Streptomyces spp. †  

PubMed Central

Previous investigations have identified a quantitatively major intermediate of lignin degradation by Streptomyces viridosporus. The intermediate, a modified lignin polymer, acid-precipitable polymeric lignin (APPL), is released as a water-soluble catabolite and has been recovered in amounts equivalent to 30% of the lignin originally present in a corn stover lignocellulose substrate after degradation by this actinomycete. In the present work, APPLs were collected at various time intervals from cultures of two highly ligninolytic Streptomyces sp. strains, S. viridosporus T7A and S. badius 252, growing on corn stover lignocellulose. APPL production was measured over time, and the chemistry of APPLs produced by each organism after different time intervals was compared. Chemical characterizations included assays for lignin, carbohydrate, and ash contents, molecular weight distributions by gel permeation chromatography, and chemical degradation analyses by permanganate oxidation, acidolysis, and alkaline ester hydrolysis. Differences between the organisms were observed in the cultural conditions required for APPL production and in the time courses of APPL accumulation. S. viridosporus produced APPL in solid-state fermentation over a 6- to 8-week incubation period, whereas S. badius produced as much or more APPL, but only in liquid culture and over a 7- to 8-day incubation period. The chemistry of the APPLs produced also differed. S. viridosporus APPL was more lignin-like than that of S. badius and was slowly modified further over time, although no change in molecular weight distribution over time was observed. In contrast, S. badius APPL was less lignin-like and increased substantially in average molecular weight over time. Results indicated that differing mechanisms of lignin metabolism may exist in these two Streptomyces sp. strains. S. viridosporus APPL probably originates from the heart of the lignin and is released largely as the result of ?-ether cleavage and other oxidative reactions. S. badius APPL probably originates in the same manner; however, after release as a water-soluble catabolite, lower-molecular-weight intermediates of lignin degradation are repolymerized with APPL in a reaction catalyzed by an extracellular phenol oxidase. The chemical analyses and the presence of extracellular phenol oxidase in S. badius, but not in S. viridosporus, support this conclusion. PMID:16346714

Borgmeyer, Jeffry R.; Crawford, Don L.

1985-01-01

398

Hydrogeologic framework and sampling design for an assessment of agricultural pesticides in ground water in Pennsylvania  

USGS Publications Warehouse

State agencies responsible for regulating pesticides are required by the U.S. Environmental Protection Agency to develop state management plans for specific pesticides. A key part of these management plans includes assessing the potential for contamination of ground water by pesticides throughout the state. As an example of how a statewide assessment could be implemented, a plan is presented for the Commonwealth of Pennsylvania to illustrate how a hydrogeologic framework can be used as a basis for sampling areas within a state with the highest likelihood of having elevated pesticide concentrations in ground water. The framework was created by subdividing the state into 20 areas on the basis of physiography and aquifer type. Each of these 20 hydrogeologic settings is relatively homogeneous with respect to aquifer susceptibility and pesticide use?factors that would be likely to affect pesticide concentrations in ground water. Existing data on atrazine occurrence in ground water was analyzed to determine (1) which areas of the state already have suffi- cient samples collected to make statistical comparisons among hydrogeologic settings, and (2) the effect of factors such as land use and aquifer characteristics on pesticide occurrence. The theoretical vulnerability and the results of the data analysis were used to rank each of the 20 hydrogeologic settings on the basis of vulnerability of ground water to contamination by pesticides. Example sampling plans are presented for nine of the hydrogeologic settings that lack sufficient data to assess vulnerability to contamination. Of the highest priority areas of the state, two out of four have been adequately sampled, one of the three areas of moderate to high priority has been adequately sampled, four of the nine areas of moderate to low priority have been adequately sampled, and none of the three low priority areas have been sampled. Sampling to date has shown that, even in the most vulnerable hydrogeologic settings, pesticide concentrations in ground water rarely exceed U.S. Environmental Protection Agency Drinking Water Standards or Health Advisory Levels. Analyses of samples from 1,159 private water supplies reveal only 3 sites for which samples with concentrations of pesticides exceeded drinking-water standards. In most cases, samples with elevated concentrations could be traced to point sources at pesticide loading or mixing areas. These analyses included data from some of the most vulnerable areas of the state, indicating that it is highly unlikely that pesticide concentrations in water from wells in other areas of the state would exceed the drinking-water standards unless a point source of contamination were present. Analysis of existing data showed that water from wells in areas of the state underlain by carbonate (limestone and dolomite) bedrock, which commonly have a high percentage of corn production, was much more likely to have pesticides detected. Application of pesticides to the land surface generally has not caused concentrations of the five state priority pesticides in ground water to exceed health standards; however, this study has not evaluated the potential human health effects of mixtures of pesticides or pesticide degradation products in drinking water. This study also has not determined whether concentrations in ground water are stable, increasing, or decreasing.

Lindsey, Bruce D.; Bickford, Tammy M.

1999-01-01

399

Antibiotic, pesticide, and microbial contaminants of honey: human health hazards.  

PubMed

Agricultural contamination with pesticides and antibiotics is a challenging problem that needs to be fully addressed. Bee products, such as honey, are widely consumed as food and medicine and their contamination may carry serious health hazards. Honey and other bee products are polluted by pesticides, heavy metals, bacteria and radioactive materials. Pesticide residues cause genetic mutations and cellular degradation and presence of antibiotics might increase resistant human or animal's pathogens. Many cases of infant botulisms have been attributed to contaminated honey. Honey may be very toxic when produced from certain plants. Ingestion of honey without knowing its source and safety might be problematic. Honey should be labeled to explore its origin, composition, and clear statement that it is free from contaminants. Honey that is not subjected for analysis and sterilization should not be used in infants, and should not be applied to wounds or used for medicinal purposes. This article reviews the extent and health impact of honey contamination and stresses on the introduction of a strict monitoring system and validation of acceptable minimal concentrations of pollutants or identifying maximum residue limits for bee products, in particular, honey. PMID:23097637

Al-Waili, Noori; Salom, Khelod; Al-Ghamdi, Ahmed; Ansari, Mohammad Javed

2012-01-01

400

Portable Bioactive Paper-Based Sensor for Quantification of Pesticides  

PubMed Central

A paper-based biosensor was developed for the detection of the degradation products of organophosphorus pesticides. The biosensor quantifies acetylcholine esterase inhibitors in a fast, disposable, cheap, and accurate format. We specifically focused on the use of sugar or protein stabilizer to achieve a biosensor with long shelf-life. The new biosensor detected malathion with a detection limit of 2.5?ppm in 5?min incubation time. The operational stability was confirmed by testing 60 days storage at 4°C when glucose was used as stabilizer. PMID:23971002

Kavruk, Murat; Ozalp, Veli Cengiz; Oktem, Huseyin Avni

2013-01-01

401

Safe Storage of Pesticides  

MedlinePLUS

Safe Storage of Pesticides Esta página Web está disponible en espańol Improper pesticide storage and disposal can be hazardous to human health ... Follow these safety recommendations: Don't stockpile. Reduce storage needs by buying only the amount of pesticide ...

402

Carbon capture and sequestration: an exploratory inhalation toxicity assessment of amine-trapping solvents and their degradation products.  

PubMed

Carbon dioxide (CO2) absorption with aqueous amine solvents is a method of carbon capture and sequestration (CCS) from flue gases. One concern is the possible release of amine solvents and degradation products into the atmosphere, warranting evaluation of potential pulmonary effects from inhalation. The CCS amines monoethanolamine (MEA), methyldiethanolamine (MDEA), and piperazine (PIP) underwent oxidative and CO2-mediated degradation for 75 days. C57bl/6N mice were exposed for 7 days by inhalation of 25 ppm neat amine or equivalant concentration in the degraded mixture. The aqueous solutions were nebulized to create the inhalation atmospheres. Pulmonary response was measured by changes in inflammatory cells in bronchoalveolar lavage fluid and cytokine expression in lung tissue. Ames mutagenicity and CHO-K1 micronucleus assays were applied to assess genotoxicity. Chemical analysis of the test atmosphere and liquid revealed complex mixtures, including acids, aldehydes, and other compounds. Exposure to oxidatively degraded MEA increased (p < 0.05) total cells, neutrophils, and lymphocytes compared to control mice and caused inflammatory cytokine expression (statistical increase at p < 0.05). MEA and CO2-degraded MEA were the only atmospheres to show statistical (p < 0.05) increase in oxidative stress. CO2 degradation resulted in a different composition, less degradation, and lower observed toxicity (less magnitude and number of effects) with no genotoxicity. Overall, oxidative degradation of the amines studied resulted in enhanced toxicity (increased magnitude and number of effects) compared to the neat chemicals. PMID:25167095

McDonald, Jacob D; Kracko, Dean; Doyle-Eisele, Melanie; Garner, C Edwin; Wegerski, Chris; Senft, Al; Knipping, Eladio; Shaw, Stephanie; Rohr, Annette

2014-09-16

403

Degradation products from consumer nanocomposites - a case study on quantum dot lighting  

PubMed Central

Most nanomaterials enter the natural environment as nano-enabled products, which are typically composites with primary nanoparticles bound on substrates or embedded in liquid or solid matrices. The environmental risks associated with these products are expected to differ from those associated with the as-produced particles. This article presents a case study on the end-of-life emission of a commercial prototype polymer/quantum-dot (QD) composite used in solid-state lighting for homes. We report the extent of cadmium release upon exposure to a series of environmental and biological simulant fluids, and track the loss of QD-characteristic fluorescence as a marker for chemical damage to the CdSe/ZnS nanoparticles. Measured cadmium releases after 30-day exposure range from 0.007-1.2 mg/g of polymer, and the higher values arise for low-pH simulants containing nitric or gastric acid. Centrifugal ultrafiltration and ICP was used to distinguish soluble cadmium from particulate forms. The leachate is found to contain soluble metals with no evidence of free QDs or QD-containing polymeric debris. The absence of free nanoparticles suggests that this product does not raise nanotechnology-specific environmental issues associated with degradation and leaching, but is more usefully regarded as a conventional chemical product that is a potential source of small amounts of soluble cadmium. PMID:22352378

Liu, Jingyu; Katahara, John; Li, Guanglai; Coe-Sullivan, Seth; Hurt, Robert H.

2012-01-01

404

Degradation of organic compounds and production of activated species in Dielectric Barrier Discharges and Glidarc reactors  

E-print Network

Major sterilization mechanisms are related to atoms and radicals, charged parti-cles, excited molecules, ozone, and UV radiation. The ROS (Reactive Oxygen Species) are well known as evildoers. These species are easily created in ambient air and water and they live long enough to reach the cell and attack the organic matter. Test molecules conversion in dry and wet air is studied using Dielectric Barrier Discharge (DBD) and Gliding Arc Reactors (GAR). The effects of tem-perature and energy deposition into the media on the active species production and then on the organic compounds degradation are presented for two non thermal plasma reactors: DBD and GAR. Main production species investigated are OH, O3, NOx, CO and CxHyOz by-products. It is shown from experiment analysis that the reactive species production is quite different from one reactor to another. GAR and pulsed DBD are two chemical processing ways in which the temperature of heavy species in ionized gas is determinant. By reviewing the species producti...

Cormier, Jean Marie; Khacef, Ahmed

2008-01-01

405

Impurity profiling of trandolapril under stress testing: Structure elucidation of by-products and development of degradation pathway.  

PubMed

Various regulatory authorities like International Conference on Harmonization (ICH), US Food and Drug Administration, Canadian Drug and Health Agency are emphasizing on the purity requirements and the identification of impurities in active pharmaceutical drugs. Qualification of the impurities is the process of acquiring and evaluating data that establishes biological safety of an individual impurity; thus, revealing the need and scope of impurity profiling of drugs in pharmaceutical research. As no stability-indicating method is available for identification of degradation products of trandolapril, a new angiotensin converting enzyme inhibitor (ACEI), under stress testing, the development of an accurate method is needed for quantification and qualification of degradation products. Ultra high performance liquid chromatography (UPLC) coupled to electrospray tandem mass spectrometry was used for the rapid and simultaneous analysis of trandolapril and its degradation products. Chromatographic separation was achieved in less than 4 min, with improved peak resolution and sensitivity. Thanks to this method, the kinetics of trandolapril degradation under various operating conditions and the characterization of the structure of the by-products formed during stress testing have been determined. Thereafter, a mechanism of trandolapril degradation in acid and neutral conditions, including all the identified products, was then proposed. PMID:22960502

Dendeni, M; Cimetiere, N; Amrane, A; Hamida, N Ben

2012-11-15

406

Age-related changes in collagen synthesis and degradation in rat tissues. Importance of degradation of newly synthesized collagen in regulating collagen production.  

PubMed Central

During developmental growth, collagens are believed to be continuously deposited into an extracellular matrix which is increasingly stabilized by the formation of covalent cross-links throughout life. However, the age-related changes in rates of synthetic and degradative processes are less well understood. In the present study we measured rates of collagen synthesis in vivo using a flooding dose of unlabelled proline given with [14C]proline and determining production of hydroxy[14C]proline. Degradation of newly synthesized collagen was estimated from the amount of free hydroxy [14C]proline in tissues 30 min after injection. Collagen fractional synthesis rates ranged from about 5%/day in skeletal muscle to 20%/day in hearts of rats aged 1 month. At 15 months of age, collagen fractional synthesis rates had decreased markedly in lung and skin, but in skeletal muscle and heart, rates were unchanged. At 24 months of age, synthesis rates had decreased by at least 10-fold in all tissues, compared with rates at 1 month. The proportion of newly synthesized collagen degraded ranged from 6.4 +/- 0.4% in skin to 61.6 +/- 5.0% in heart at 1 month of age. During aging the proportion degraded increased in all tissues to maximal values at 15 months, ranging from 56 +/- 7% in skin to 96 +/- 1% in heart. These data suggest that there are marked age-related changes in rates of collagen metabolism. They also indicate that synthesis is active even in old animals, where the bulk of collagens produced are destined to be degraded. PMID:2049064

Mays, P K; McAnulty, R J; Campa, J S; Laurent, G J

1991-01-01

407

Household Products Database: Pesticides  

MedlinePLUS

... cats fertilizer w/insecticide fertilizer w/weed control fire ants flea & tick control fleas fleas/ticks flowers ... carpenter ants/bees ticks tomatoes total vegetation control tree trees trees, flowering trees, fruit trees, nut trees, ...

408

Urinary fibrin (-ogen) degradation products in Russell's viper (Daboia russelii siamensis) bite victims.  

PubMed

Serum and urine concentrations of fibrin (-ogen) degradation products (FDP) were estimated in 20 proven Russell's viper bite (RVB) cases with severe defribination. All patients had similar degrees of high serum FDP levels. However, the ten who developed into acute renal failure (ARF) had significantly (p < 0.001) higher urinary FDP levels than those who did not. The urinary FDP levels of ARF cases increased correspondingly with high serum FDP levels but not in cases without ARF. Serial comparison of serum and urinary FDP levels in RVB cases with severe defibrination may be of value in predicting the likelihood of developing ARF. The present study favored disseminated intravascular coagulation as the main cause of ARF in Myanmar RVB cases. PMID:8362297

Han, K E; Than, T; Lwin, M; Swe, T N; Pe, T

1993-03-01

409

Gas production due to alpha particle degradation of polyethylene and polyvinylchloride  

SciTech Connect

Alpha particle degradation experiments were performed on polyethylene (PE) and polyvinylchloride (PVC) plastic samples typical of Westinghouse Savannah River Company (WSRC) transuranic (TRU) waste. This was done to evaluate the effects of sealing TRU waste during shipment. Experiments were conducted at three temperatures using low dose rates. Predominant products from both plastics were hydrogen, carbon dioxide, and various organic species, with the addition of hydrochloric acid from PVC. In all experiments, the total pressure decreased. Irradiation at 30 and 60 C and at various dose rates caused small changes for both plastics, but at 100 C coupled thermal-radiolytic effects included discoloration of the material as well as large differences in the gas phase composition.

Reed, D.T.; Hoh, J.; Emery, J.; Okajima, S.; Krause, T.

1998-07-01

410

RESEARCH ARTICLE Blocking the Metabolism of Starch Breakdown Products in Arabidopsis Leaves Triggers Chloroplast Degradation  

E-print Network

ABSTRACT In most plants, a large fraction of photo-assimilated carbon is stored in the chloroplasts during the day as starch and remobilized during the subsequent night to support metabolism. Mutations blocking either starch synthesis or starch breakdown in Arabidopsis thaliana reduce plant growth. Maltose is the major product of starch breakdown exported from the chloroplast at night. The maltose excess 1 mutant (mex1), which lacks the chloroplast envelope maltose transporter, accumulates high levels of maltose and starch in chloroplasts and develops a distinctive but previously unexplained chlorotic phenotype as leaves mature. The introduction of additional mutations that prevent starch synthesis, or that block maltose production from starch, also prevent chlorosis of mex1. In contrast, introduction of mutations in disproportionating enzyme (DPE1) results in the accumulation of maltotriose in addition to maltose, and greatly increases chlorosis. These data suggest a link between maltose accumulation and chloroplast homeostasis. Microscopic analyses show that the mesophyll cells in chlorotic mex1 leaves have fewer than half the number of chloroplasts than wild-type cells. Transmission electron microscopy reveals autophagy-like chloroplast degradation in both mex1 and the dpe1/mex1 double mutant. Microarray analyses reveal substantial reprogramming of metabolic and cellular processes, suggesting that organellar protein turnover is increased in mex1, though leaf senescence and senescence-related chlorophyll catabolism are not induced. We propose that the accumulation of maltose and malto-oligosaccharides causes chloroplast dysfunction, which may by signaled via a form of retrograde signaling and trigger chloroplast degradation.

Michaela Stettler A; Simona Eicke A; Tabea Mettler A; Gaëlle Messerli A; Stefan Hörtensteiner B; Samuel C. Zeeman A

2009-01-01

411

Blocking the Metabolism of Starch Breakdown Products in Arabidopsis Leaves Triggers Chloroplast Degradation  

PubMed Central

In most plants, a large fraction of photo-assimilated carbon is stored in the chloroplasts during the day as starch and remobilized during the subsequent night to support metabolism. Mutations blocking either starch synthesis or starch breakdown in Arabidopsis thaliana reduce plant growth. Maltose is the major product of starch breakdown exported from the chloroplast at night. The maltose excess 1 mutant (mex1), which lacks the chloroplast envelope maltose transporter, accumulates high levels of maltose and starch in chloroplasts and develops a distinctive but previously unexplained chlorotic phenotype as leaves mature. The introduction of additional mutations that prevent starch synthesis, or that block maltose production from starch, also prevent chlorosis of mex1. In contrast, introduction of mutations in disproportionating enzyme (DPE1) results in the accumulation of maltotriose in addition to maltose, and greatly increases chlorosis. These data suggest a link between maltose accumulation and chloroplast homeostasis. Microscopic analyses show that the mesophyll cells in chlorotic mex1 leaves have fewer than half the number of chloroplasts than wild-type cells. Transmission electron microscopy reveals autophagy-like chloroplast degradation in both mex1 and the dpe1/mex1 double mutant. Microarray analyses reveal substantial reprogramming of metabolic and cellular processes, suggesting that organellar protein turnover is increased in mex1, though leaf senescence and senescence-related chlorophyll catabolism are not induced. We propose that the accumulation of maltose and malto-oligosaccharides causes chloroplast dysfunction, which may by signaled via a form of retrograde signaling and trigger chloroplast degradation. PMID:19946617

Stettler, Michaela; Eicke, Simona; Mettler, Tabea; Messerli, Gaelle; Hortensteiner, Stefan; Zeeman, Samuel C.

2009-01-01

412

Effect of fiber and dye degradation products (FDP) on burn wound healing.  

PubMed

Upon exposure to the thermal environment of an aircraft fire, many fire retardant fabrics off-gas fiber and dye degradation products (FDP). Condensation of these products on human skin raises questions concerning possible deleterious effects on burn wound healing. A porcine bioassay was used to study the physiological effects of FDP. Selected areas of living skin, protected by dyed aromatic polyamides and polybenzimidazole fabrics, were exposed to a thermal source adjusted to simulate a postcrash JP-4 fuel fire. Burn sites contaminated with FDP were evaluated by clinical observation ane to begin epithelialization, time to closure of an open wound, and the amount and type of cicatrix formation. The experiment showed that each fabric has unique off-gasing products. The greatest amount of FDP was deposited on the skin when the skin was covered by a single layer of shell fabric separated by a 6.35-mm air gap. The presence of an intervening cotton T-shirt decreased the amount of FDP deposited on the skin. We found no evidence that FDP caused alterations in wound healing. PMID:518442

Knox, F S; Wachtel, T L; McCahan, G R; Knapp, S C

1979-10-01

413

Heterologous expression of plant cell wall degrading enzymes for effective production of cellulosic biofuels.  

PubMed

A major technical challenge in the cost-effective production of cellulosic biofuel is the need to lower the cost of plant cell wall degrading enzymes (PCDE), which is required for the production of sugars from biomass. Several competitive, low-cost technologies have been developed to produce PCDE in different host organisms such as Escherichia coli, Zymomonas mobilis, and plant. Selection of an ideal host organism is very important, because each host organism has its own unique features. Synthetic biology-aided tools enable heterologous expression of PCDE in recombinant E. coli or Z. mobilis and allow successful consolidated bioprocessing (CBP) in these microorganisms. In-planta expression provides an opportunity to simplify the process of enzyme production and plant biomass processing and leads to self-deconstruction of plant cell walls. Although the future of currently available technologies is difficult to predict, a complete and viable platform will most likely be available through the integration of the existing approaches with the development of breakthrough technologies. PMID:22911272

Jung, Sang-Kyu; Parisutham, Vinuselvi; Jeong, Seong Hun; Lee, Sung Kuk

2012-01-01

414

Contact allergy due to colophony. (IX). Sensitization studies with further products isolated after oxidative degradation of resin acids and colophony.  

PubMed

Degradation of abietic, levopimaric and dehydroabietic acids after exposure to air and light over a period of one to several months, as well as examination of degraded French tall oil rosin and Portuguese colophony, led to the isolation of numerous oxidation products. These compounds were synthesized and consigned to experimental sensitization in guinea pigs. From 20 substances studied as acids or as their methyl esters, in the present and preceding paper, at least 2 can be named: 8,12-peroxydo-delta 13(14)-dihydroabietic acid and 12 alpha-hydroxyabietic acid, that contribute a great deal to colophony allergy by both their sensitizing capacity and their determined concentration in the mixture of degradation products. We recommend the preparation of a new mixture of colophony oxidation products for patch testing in the diagnosis of contact allergy to colophony. PMID:8112061

Hausen, B M; Börries, M; Budianto, E; Krohn, K

1993-11-01

415

Identification and Characterization of an Oxidative Degradation Product of Fexofenadine, Development and Validation of a Stability-Indicating RP-UPLC Method for the Estimation of Process Related Impurities and Degradation Products of Fexofenadine in Pharmaceutical Formulations.  

PubMed

A novel stability-indicating gradient RP-UPLC method was developed for the quantitative determination of process related impurities and forced degradation products of fexofenadine HCl in pharmaceutical formulations. The method was developed by using Waters Aquity BEH C18 (100 mm x 2.1 mm) 1.7 ?m column with mobile phase containing a gradient mixture of solvent A (0.05% triethyl amine, pH adjusted to 7.0 with ortho-phosphoric acid) and B (10:90 v/v mixture of water and acetonitrile). The flow rate of mobile phase was 0.4 mL/min with column temperature of 30°C and detection wavelength at 220nm. Fexofenadine HCl was subjected to the stress conditions including oxidative, acid, base, hydrolytic, thermal and photolytic degradation. Fexofenadine HCl was found to degrade significantly in oxidative stress conditions, and degradation product was identified and characterized by ESI-MS/MS, (1)H and (13)C NMR spectroscopic method as the N-oxide 2-[4-(1-hydroxy-4-{4-[hydroxy(diphenyl)methyl]-1-oxido-piperidin-1-yl}butyl)phenyl]-2-methylpropanoic acid. The degradation products were well resolved from fexofenadine and its impurities. The mass balance was found to be satisfactory in all the stress conditions, thus proving the stability-indicating capability of the method. The developed method was validated as per ICH guidelines with respect to specificity, linearity, limit of detection and quantification, accuracy, precision and robustness. PMID:22896817

Vaghela, Bhupendrasinh; Rao, Surendra Singh; Reddy, Annarapu Malleshwar; Venkatesh, Panuganti; Kumar, Navneet

2012-06-01

416

SOURCE ASSESSMENT: PESTICIDE MANUFACTURING AIR EMISSIONS--OVERVIEW AND PRIORITIZATION  

EPA Science Inventory

The report is an overview of the pesticide manufacturing industry and prioritizes 80 major pesticides based on their potential environmental burden from an air pollution standpoint. Production of synthetic organic pesticides was about 640,000 metric tons in 1974. Thirty-seven maj...

417

Pesticide Labeling: Miscellaneous Label Parts1 Frederick M. Fishel2  

E-print Network

PI-109 Pesticide Labeling: Miscellaneous Label Parts1 Frederick M. Fishel2 1. This document is PI. Fishel, professor, Agronomy Department, and Director, Pesticide Information Office; Florida Cooperative not signify our approval to the exclusion of other products of suitable composition. Use pesticides safely

Watson, Craig A.

418

Pesticide Labeling: Identification Numbers1 Frederick M. Fishel2  

E-print Network

PI-108 Pesticide Labeling: Identification Numbers1 Frederick M. Fishel2 1. This document is PI-108, professor, Agronomy Department, and Director, Pesticide Information Office; Florida Cooperative Extension not signify our approval to the exclusion of other products of suitable composition. Use pesticides safely

Watson, Craig A.

419

Various laws require that pesticide applicators be educated about the  

E-print Network

Various laws require that pesticide applicators be educated about the safe application of chemicals organisms may die as a result of pesticide contamina- tion, or they may simply grow poorly, become more a pesticide must be used, select a product that is regis- tered for the use intended and is the least toxic

Florida, University of

420

77 FR 76979 - Pesticides; Revisions to Minimum Risk Exemption  

Federal Register 2010, 2011, 2012, 2013

...EPA-HQ-OPP-2010-0305; FRL-9339-1] RIN 2070-AJ79 Pesticides; Revisions to Minimum Risk Exemption...exemption from regulation for minimum risk pesticides. EPA is proposing to reorganize these...ingredients are permitted in minimum risk pesticide products. EPA is also proposing...

2012-12-31

421

How agro-ecological research helps to address food security issues under new IPM and pesticide reduction policies for global crop production systems.  

PubMed

Drivers behind food security and crop protection issues are discussed in relation to food losses caused by pests. Pests globally consume food estimated to feed an additional one billion people. Key drivers include rapid human population increase, climate change, loss of beneficial on-farm biodiversity, reduction in per capita cropped land, water shortages, and EU pesticide withdrawals under policies relating to 91/414 EEC. IPM (Integrated Pest Management) will be compulsory for all EU agriculture by 2014 and is also being widely adopted globally. IPM offers a 'toolbox' of complementary crop- and region-specific crop protection solutions to address these rising pressures. IPM aims for more sustainable solutions by using complementary technologies. The applied research challenge now is to reduce selection pressure on single solution strategies, by creating additive/synergistic interactions between IPM components. IPM is compatible with organic, conventional, and GM cropping systems and is flexible, allowing regional fine-tuning. It reduces pests below economic thresholds utilizing key 'ecological services', particularly biocontrol. A recent global review demonstrates that IPM can reduce pesticide use and increase yields of most of the major crops studied. Landscape scale 'ecological engineering', together with genetic improvement of new crop varieties, will enhance the durability of pest-resistant cultivars (conventional and GM). IPM will also promote compatibility with semiochemicals, biopesticides, precision pest monitoring tools, and rapid diagnostics. These combined strategies are urgently needed and are best achieved via multi-disciplinary research, including complex spatio-temporal modelling at farm and landscape scales. Integrative and synergistic use of existing and new IPM technologies will help meet future food production needs more sustainably in developed and developing countries, in an era of reduced pesticide availability. Current IPM research gaps are identified and discussed. PMID:21669880

E Birch, A Nicholas; Begg, Graham S; Squire, Geoffrey R

2011-06-01

422

Pesticides Removal Using Plants: Phytodegradation Versus Phytostimulation  

Microsoft Academic Search

Pesticides are chemicals used for crop protection and pest control, and are probably the most widely distributed contaminants in the environment over the last century. Although it is extremely difficult to obtain precise figures concerning their production and use per country [1], millions of tons of pesticides are produced and spread annually all over the world. Thousands of different synthetic

Jean-Paul Schwitzguébel; Joana Meyer; Petra Kidd

423

Using Pesticides Safely. Special Circular 296.  

ERIC Educational Resources Information Center

The use of pesticides is necessary to aid in the production of food, feed and fiber, and is equally important in the control of home garden and household pests, but correct use is critical in preventing injury to persons, animals, and plants. This circular contains information on State of Pennsylvania and federal pesticide laws; different types of…

Hock, W. K.

424

Persistent pesticides in Mexico.  

PubMed

As part of the recent increase in the international interest in persistent organic pollutants and their environmental and health hazards, it was found that although most of them have been severely controlled in developed countries, in most developing countries--including Mexico--their import, use, and in some cases production have continued up to the present without sufficient or adequate controls. Despite the large and continuing use of persistent organic chemicals in Mexico in agriculture, public health, and industry, data on their import, production, use, disposal, and the presence of their residues in the environment, food, and human tissues are extremely scarce and widely dispersed. This review is devoted only to the use of persistent pesticides in Mexico; it is the first effort to locate, gather, and analyze this information and to summarize and discuss the past and current situation of the control of these chemicals in Mexico. This review discusses the general background for the use of these pesticides in the country, including historical development, the reasons for substitution by less persistent products in crops intended for export, and the undesirable effect of this substitution on the health of migratory agricultural workers. The current status of the legal framework for the control of pesticides in Mexico is presented with emphasis on its slow and haphazard development; the legal, technical, and administrative reasons for the insufficient enforcement and oversight of the existing regulations and standards are highlighted. The low priority of this research area for the Mexican science and technology authorities and the negative consequences of this low priority on the existence of sufficient reliable data on pesticide residues in the environment and humans in Mexico are also discussed. The available data on production and uses of persistent pesticides in Mexico are presented, and the existing information on their residues in the environment, biota, food, and human tissues in the country is summarized; maps with the location of the main studies are included to stress the lack of information for most of the country, especially for remote areas and regions of agriculture devoted to crops for local, domestic, or self-consumption. The major characteristics of these studies are discussed in specific sections and, on this basis, a general comment on the current situation and forecast for the near future is made. The conclusions summarize the information presented, with particular emphasis on the need to improve and update the legal framework and strengthen the technical and administrative infrastructure essential for the oversight and control of the regulations. The urgency of carrying out new studies, in particular interdisciplinary studies, to establish the current pattern for pollution by these chemicals in Mexico is stressed. PMID:8776984

Albert, L A

1996-01-01

425

Contributions of long-range and regional atmospheric transport on pesticide concentrations along a transect crossing a mountain divide.  

PubMed

Twenty-one halogenated legacy and current-use pesticides and pesticide degradation products were measured in pine needles along a coast-to-coast transect that crossed the Southern Alps of New Zealand. Concentration profiles of nine pesticides were used to determine the influence of geographic sources on the atmospheric pesticide burden at the mountain sites. Pesticide concentration profiles were calculated for each source and mountain site by normalizing concentrations (adjusted for temperature at the site and air-needle partitioning) to the sum of all pesticide concentrations at the site. Each mountain site profile was compared to varying mixtures of the potential source profiles to determine the percent contribution of each source. The highest elevation mountain sites were primarily influenced by long-range, synoptic-scale northwesterly winds. Westerly upslope winds had little influence on any of the mountain sites. Easterly upslope winds from the Canterbury Plains, an agricultural region, strongly influenced the mountain sites within close proximity and had progressively less influence with distance. PMID:23252430

Lavin, Karen S; Hageman, Kimberly J

2013-02-01

426

TLC-UV and VIS Densitometric Detection Method for Determination of Oxyphenonium Bromide and its Degradation Products in Tablets  

Microsoft Academic Search

A chromatographic-densitometric method was developed for determination of oxyhyphenonium bromide and its degradation products under UV\\/VIS spectra. Silica gel TLCF254 plates were used as stationary phase and butanol-1–glacial acetic acid–water (12.8:2:2.8 v\\/v\\/v) as mobile phase. Densitometric measurements were done at ? ? 225 nm and ? ? 530 nm. Degradation products ?-cyclohexyl-?-hydroxybenzeneacetic acid and N,N-diethyl-N-methylaminethanol were determined by HNMR method. The chromatographic-densitometric method is specific for

Urszula Hubicka; Jan Krzek; Olga Szczyrbowska

2009-01-01

427

The occurrence of glyphosate, atrazine, and other pesticides in vernal pools and adjacent streams in Washington, DC, Maryland, Iowa, and Wyoming, 2005-2006.  

PubMed

Vernal pools are sensitive environments that provide critical habitat for many species, including amphibians. These small water bodies are not always protected by pesticide label requirements for no-spray buffer zones, and the occurrence of pesticides in them is poorly documented. In this study, we investigated the occurrence of glyphosate, its primary degradation product aminomethylphosphonic acid, and additional pesticides in vernal pools and adjacent flowing waters. Most sampling sites were chosen to be in areas where glyphosate was being used either in production agriculture or for nonindigenous plant control. The four site locations were in otherwise protected areas (e.g., in a National Park). When possible, water samples were collected both before and after glyphosate application in 2005 and 2006. Twenty-eight pesticides or pesticide degradation products were detected in the study, and as many as 11 were identified in individual samples. Atrazine was detected most frequently and concentrat