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Sample records for acute zinc toxicity

  1. Acute toxicity and accumulation of zinc in the crayfish, Orconectes virilis (Hagen)

    SciTech Connect

    Not Available

    1986-09-01

    Zinc produces acute toxicity to freshwater organisms over a range of concentrations from 90 to 58, 100..mu..g Zn/L; with the range of acute median effect concentrations being similar for freshwater fish and invertebrates. The capacity to regulate internal zinc concentrations in decapod crustaceans has been described. Studies with the crayfish Austropotambius pallipes suggested a relatively high degree of tolerance to zinc by this animal. The present study is designed to describe the toxicity of zinc to the crayfish Orconectes virilis over a 2-wk exposure period. In addition, whole animal and tissue analyses were performed on the test organisms and compared to previous results.

  2. Acute oral toxicity and biodistribution study of zinc-aluminium-levodopa nanocomposite.

    PubMed

    Kura, Aminu Umar; Saifullah, Bullo; Cheah, Pike-See; Hussein, Mohd Zobir; Azmi, Norazrina; Fakurazi, Sharida

    2015-01-01

    Layered double hydroxide (LDH) is an inorganic-organic nano-layered material that harbours drug between its two-layered sheets, forming a sandwich-like structure. It is attracting a great deal of attention as an alternative drug delivery (nanodelivery) system in the field of pharmacology due to their relative low toxic potential. The production of these nanodelivery systems, aimed at improving human health through decrease toxicity, targeted delivery of the active compound to areas of interest with sustained release ability. In this study, we administered zinc-aluminium-LDH-levodopa nanocomposite (ZAL) and zinc-aluminium nanocomposite (ZA) to Sprague Dawley rats to evaluate for acute oral toxicity following OECD guidelines. The oral administration of ZAL and ZA at a limit dose of 2,000 mg/kg produced neither mortality nor acute toxic signs throughout 14 days of the observation. The percentage of body weight gain of the animals showed no significant difference between control and treatment groups. Animal from the two treated groups gained weight continuously over the study period, which was shown to be significantly higher than the weight at the beginning of the study (P < 0.05). Biochemical analysis of animal serum showed no significant difference between rats treated with ZAL, ZA and controls. There was no gross lesion or histopathological changes observed in vital organs of the rats. The results suggested that ZAL and ZA at 2,000 mg/kg body weight in rats do not induce acute toxicity in the animals. Elemental analysis of tissues of treated animals demonstrated the wider distribution of the nanocomposite including the brain. In summary, findings of acute toxicity tests in this study suggest that zinc-aluminium nanocomposite intercalated with and the un-intercalated were safe when administered orally in animal models for short periods of time. It also highlighted the potential distribution ability of Tween-80 coated nanocomposite after oral administration.

  3. Acute oral toxicity and biodistribution study of zinc-aluminium-levodopa nanocomposite

    NASA Astrophysics Data System (ADS)

    Kura, Aminu Umar; Saifullah, Bullo; Cheah, Pike-See; Hussein, Mohd Zobir; Azmi, Norazrina; Fakurazi, Sharida

    2015-03-01

    Layered double hydroxide (LDH) is an inorganic-organic nano-layered material that harbours drug between its two-layered sheets, forming a sandwich-like structure. It is attracting a great deal of attention as an alternative drug delivery (nanodelivery) system in the field of pharmacology due to their relative low toxic potential. The production of these nanodelivery systems, aimed at improving human health through decrease toxicity, targeted delivery of the active compound to areas of interest with sustained release ability. In this study, we administered zinc-aluminium-LDH-levodopa nanocomposite (ZAL) and zinc-aluminium nanocomposite (ZA) to Sprague Dawley rats to evaluate for acute oral toxicity following OECD guidelines. The oral administration of ZAL and ZA at a limit dose of 2,000 mg/kg produced neither mortality nor acute toxic signs throughout 14 days of the observation. The percentage of body weight gain of the animals showed no significant difference between control and treatment groups. Animal from the two treated groups gained weight continuously over the study period, which was shown to be significantly higher than the weight at the beginning of the study ( P < 0.05). Biochemical analysis of animal serum showed no significant difference between rats treated with ZAL, ZA and controls. There was no gross lesion or histopathological changes observed in vital organs of the rats. The results suggested that ZAL and ZA at 2,000 mg/kg body weight in rats do not induce acute toxicity in the animals. Elemental analysis of tissues of treated animals demonstrated the wider distribution of the nanocomposite including the brain. In summary, findings of acute toxicity tests in this study suggest that zinc-aluminium nanocomposite intercalated with and the un-intercalated were safe when administered orally in animal models for short periods of time. It also highlighted the potential distribution ability of Tween-80 coated nanocomposite after oral administration.

  4. Effects of suspended solids on the acute toxicity of zinc to Daphnia magna and Pimephales promelas

    SciTech Connect

    Hall, W.S.; Dickson, K.L.; Saleh, F.Y.; Rodgers, J.H. Jr.; Wilcox, D.; Entazami, A.

    1986-12-01

    Current procedures for setting site-specific water quality criteria consider abiotic and biotic factors. Suspended solids were shown to be important in reducing zinc toxicity to water column organisms. At zinc concentrations of approx. = 1 mg/L in solutions with < 100 mg/L of all suspended solids tested, zinc toxicity to D. magna was reduced. Sorption of zinc to suspended solids and/or changes in water chemistry due to the addition of suspended solids appear to have been the factors causing reductions in zinc toxicity to D. magna. Only suspended solids levels of 483-734 mg/L of a type that increased total alkalinity, total hardness, and total dissolved carbon clearly reduced the toxicity of approx. = 20 mg/L zinc to P. promelas. The toxic form of zinc to these organisms appears to reside in the aqueous phase. Characteristics of suspended solids did not influence the partition coefficient of zinc in sorption experiments of less than or equal to 96 h. The slopes of dose-response curves proved to be useful for assessing the potential of an organism to respond to changes in aqueous phase zinc concentrations, and may be a useful biological parameter when considering site-specific water quality criteria for chemicals.

  5. Acute toxicity of zinc to several aquatic species native to the Rocky Mountains.

    PubMed

    Brinkman, Stephen F; Johnston, Walter D

    2012-02-01

    National water-quality criteria for the protection of aquatic life are based on toxicity tests, often using organisms that are easy to culture in the laboratory. Species native to the Rocky Mountains are poorly represented in data sets used to derive national water-quality criteria. To provide additional data on the toxicity of zinc, several laboratory acute-toxicity tests were conducted with a diverse assortment of fish, benthic invertebrates, and an amphibian native to the Rocky Mountains. Tests with fish were conducted using three subspecies of cutthroat trout (Colorado River cutthroat trout Oncorhynchus clarkii pleuriticus, greenback cutthroat trout O. clarkii stomias, and Rio Grande cutthroat trout O. clarkii virginalis), mountain whitefish (Prosopium williamsoni), mottled sculpin (Cottus bairdi), longnose dace (Rhinichthys cataractae), and flathead chub (Platygobio gracilis). Aquatic invertebrate tests were conducted with mayflies (Baetis tricaudatus, Drunella doddsi, Cinygmula sp. and Ephemerella sp.), a stonefly (Chloroperlidae), and a caddis fly (Lepidostoma sp.). The amphibian test was conducted with tadpoles of the boreal toad (Bufo boreas). Median lethal concentrations (LC(50)s) ranged more than three orders of magnitude from 166 μg/L for Rio Grande cutthroat trout to >67,000 μg/L for several benthic invertebrates. Of the organisms tested, vertebrates were the most sensitive, and benthic invertebrates were the most tolerant.

  6. Acute toxicity and synergism of cadmium and zinc in white shrimp, Penaeus setiferus, Juveniles

    SciTech Connect

    Vanegas, C.; Espina, S.; Botello, A.V.; Villanueva, S.

    1997-01-01

    Toxic effects of individual heavy metals on decapod crustaceans have been reported frequently, but little information exists concerning interactions. Among the non-essential heavy metals, cadmium is one of the most hazardous elements in the aquatic environment; on the other hand, zinc is an essential element, but toxic when present in greater than trace amounts. Biological effects of cadmium in aquatic organisms are complex due to the interactions with both environmental variables and other toxic agents. In decapod crustaceans, the toxicity of cadmium and zinc is modified by salinity, temperature, hypoxia, calcium ion concentrations and life-cycle stage. Heavy metal pollution has increased in the coastal waters of the Gulf of Mexico, particularly in shrimp habitat. This study examined the toxicity of cadmium and zinc to white shrimp juveniles and looked at the interaction of the metals. 16 refs., 2 tabs.

  7. Influence of light in acute toxicity bioassays of imidacloprid and zinc pyrithione to zooplankton crustaceans.

    PubMed

    Sánchez-Bayo, Francisco; Goka, Kouichi

    2006-06-30

    The acute toxicity of imidacloprid, a neonicotinoid insecticide, and zinc pyrithione (Zpt), a biocide used in anti-dandruff shampoos and protective antifouling paints, to three species of ostracods and two waterfleas, including Daphnia magna, was determined and compared under light and dark conditions. Under normal laboratory conditions, UV light had no significant influence on the outcome of toxicity bioassays, although in the case of imidacloprid both EC(50) and LC(50) calculated values were twice as high under the light as in the dark. No influence of UV light was observed on bioassays conducted with Zpt, in spite of the fast aqueous photolysis exhibited by this compound. Imidacloprid 48-h LC(50) for cladocerans (65-133mg/L) were two orders of magnitude higher than for ostracods (301-715microg/L); values of EC(50) for cladocerans and ostracods were 2-6mg/L and 3-16microg/L, respectively. Toxicity of Zpt to both ostracod and cladoceran species appears to be similar, with 48-h LC(50) in the range 137-524 and 75-197microg/L for ostracods and cladocerans, respectively, and similar values for EC(50)s. The mortality endpoint (LC(50)), however, is not a reliable predictor of the effects of imidacloprid under field situations (e.g. rice paddies), because the paralysis effect induced by this insecticide takes place at much lower concentrations than those required to cause the death of the animals: regardless of the taxa, differences as large as 100- or 600-fold were observed between the EC(50) and LC(50) for the same exposures. As a consequence, immobilization tests and EC(50) values are recommended for this class of compounds, while caution should be exercised in environmental risk assessments of this and possibly other related neonicotinoid insecticides with similar activity.

  8. Acute and chronic toxicities of zinc pyrithione alone and in combination with copper to the marine copepod Tigriopus japonicus.

    PubMed

    Bao, Vivien W W; Lui, Gilbert C S; Leung, Kenneth M Y

    2014-12-01

    Zinc pyrithione (ZnPT) is a widely used booster biocide in combination with copper (Cu) in antifouling paints as a substitute for tributyltin. The co-occurrence of ZnPT and Cu in coastal marine environments is therefore very common, and may pose a higher risk to marine organisms if they can result in synergistic toxicity. This study comprehensively investigated the combined toxicity of ZnPT and Cu, on the marine copepod Tigriopus japonicus, for the first time, based on both 96-h acute toxicity tests using adult copepods and chronic full-life cycle tests (21 d) using nauplii <24-h old. As ZnPT has been reported to be easily trans-chelated to copper pyrithione (CuPT) in the presence of Cu, the acute toxicities of CuPT alone and in combination with Cu on adult copepods were also assessed. Our results showed that ZnPT and Cu exhibited a strong synergistic toxic effect on the copepod in both acute and chronic tests. During the acute test, the mortalities of adult copepods increased dramatically even with an addition of Cu at concentrations as low as 1-2 μg/L compared with those exposed to ZnPT alone. Severe chronic toxicities were further observed in the copepods exposed to ZnPT-Cu mixtures, including a significant increase of naupliar mortality, postponing of development from naupliar to copepodid and from copepodid to adult stage, and a significant decrease of intrinsic population growth when compared with those of copepods exposed to ZnPT or Cu alone. Such synergistic effects might be partly attributable to the formation of CuPT by the trans-chelation of ZnPT and Cu, because CuPT was found to be more toxic than ZnPT based on the acute toxicity results. Mixtures of CuPT and Cu also led to synergistic toxic effects to the copepod, in particular at high Cu concentrations. A novel non-parametric response surface model was applied and it proved to be a powerful method for analysing and predicting the acute binary mixture toxicities of the booster biocides (i.e., ZnPT and

  9. The effects of salinity on acute toxicity of zinc to two euryhaline species of fish, Fundulus heteroclitus and Kryptolebias marmoratus.

    PubMed

    Bielmyer, Gretchen K; Bullington, Joseph B; Decarlo, Carri A; Chalk, Stuart J; Smith, Kelly

    2012-12-01

    It is well known that the toxicity of zinc (Zn) varies with water chemistry and that its bioavailability is controlled by ligand interactions and competing ions. Zn toxicity in freshwaters with varying water chemistry has been well characterized; however, far less attention has been paid to the toxicity of Zn in estuarine and marine systems. We performed experiments using two euryhaline species of killifish, Fundulus heteroclitus and Kryptolebias marmoratus, to investigate the effects of changing salinity on acute toxicity of Zn. Larvae (7- to 8-days old) of each species were exposed to various concentrations of Zn for 96 h at salinities ranging from 0 to 36 ppt and survival was monitored. As salinity increased, Zn toxicity decreased in both fish species, and at salinities above 10 ppt, K. marmoratus larvae were generally more sensitive to Zn than were those of F. heteroclitus. The protection of salinity against Zn toxicity in F. heteroclitus was further investigated to determine the role of Ca(2+). Increased Ca(2+) in freshwater protected against Zn toxicity to the same extent as did saline waters with an equal Ca(2+) concentration up to ∼200 mg/L Ca for F. heteroclitus and ∼400 mg/L Ca for K. marmoratus. These results suggest that these two species may have differing Ca(2+) requirements and/or rates of Ca(2+) uptake in water of intermediate to full-strength salinity (∼200-400 mg/L Ca(2+)) and thus differ in their sensitivity to Zn. The overall goal of this study was to better understand Zn toxicity in waters of different salinity and to generate data on acute Zn toxicity from multiple species over a range of salinities, ultimately for use in development of estuarine and marine biotic ligand models.

  10. The Effects of Salinity on Acute Toxicity of Zinc to Two Euryhaline Species of Fish, Fundulus heteroclitus and Kryptolebias marmoratus

    PubMed Central

    Bielmyer, Gretchen K.; Bullington, Joseph B.; DeCarlo, Carri A.; Chalk, Stuart J.; Smith, Kelly

    2012-01-01

    It is well known that the toxicity of zinc (Zn) varies with water chemistry and that its bioavailability is controlled by ligand interactions and competing ions. Zn toxicity in freshwaters with varying water chemistry has been well characterized; however, far less attention has been paid to the toxicity of Zn in estuarine and marine systems. We performed experiments using two euryhaline species of killifish, Fundulus heteroclitus and Kryptolebias marmoratus, to investigate the effects of changing salinity on acute toxicity of Zn. Larvae (7- to 8-days old) of each species were exposed to various concentrations of Zn for 96 h at salinities ranging from 0 to 36 ppt and survival was monitored. As salinity increased, Zn toxicity decreased in both fish species, and at salinities above 10 ppt, K. marmoratus larvae were generally more sensitive to Zn than were those of F. heteroclitus. The protection of salinity against Zn toxicity in F. heteroclitus was further investigated to determine the role of Ca2+. Increased Ca2+ in freshwater protected against Zn toxicity to the same extent as did saline waters with an equal Ca2+ concentration up to ∼200 mg/L Ca for F. heteroclitus and ∼400 mg/L Ca for K. marmoratus. These results suggest that these two species may have differing Ca2+ requirements and/or rates of Ca2+ uptake in water of intermediate to full-strength salinity (∼200–400 mg/L Ca2+) and thus differ in their sensitivity to Zn. The overall goal of this study was to better understand Zn toxicity in waters of different salinity and to generate data on acute Zn toxicity from multiple species over a range of salinities, ultimately for use in development of estuarine and marine biotic ligand models. PMID:22523126

  11. Developing acute-to-chronic toxicity ratios for lead, cadmium, and zinc using rainbow trout, a mayfly, and a midge

    USGS Publications Warehouse

    Mebane, C.A.; Hennessy, D.P.; Dillon, F.S.

    2008-01-01

    In order to estimate acute-to-chronic toxicity ratios (ACRs) relevant to a coldwater stream community, we exposed rainbow trout (Oncorhynchus mykiss) to cadmium (Cd), lead (Pb), and zinc (Zn) in 96-h acute and 60+ day early-life stage (ELS) exposures. We also tested the acute and sublethal responses of a mayfly (Baetis tricaudatus) and a midge (Chironomus dilutus, formerly C. tentans) with Pb. We examine the statistical interpretation of test endpoints and the acute-to-chronic ratio concept. Increasing the number of control replicates by 2 to 3x decreased the minimum detectable differences by almost half. Pb ACR estimates mostly increased with increasing acute resistance of the organisms (rainbow trout ACRs acute tests. ?? 2007 GovernmentEmployee: U.S. Geological Survey.

  12. Novel antifouling agent zinc pyrithione: determination, acute toxicity, and bioaccumulation in marine mussels (Mytilus galloprovincialis).

    PubMed

    Marcheselli, Marco; Rustichelli, Cecilia; Mauri, Marina

    2010-11-01

    Antifouling biocide zinc pyrithione (ZnPT) and its biological fate have received little attention because this compound was assumed not to be persistent in marine ecosystems. An analytical procedure was developed that has proved to be efficient and very sensitive in extracting ZnPT and its main secondary products, Zn and ionized pyrithione (PT(-)), from both seawater and biological samples, namely in the gills and digestive gland of the bioindicator species Mytilus galloprovincialis. Short-term experiments were carried out to investigate ZnPT toxicity and bioaccumulation. The effects on survival and tissue bioaccumulation of ZnPT and its secondary products were studied on adult mussels from a natural population, collected in the harbor area of Porto Santo Stefano (Italy) and exposed to sublethal doses of the biocide for up to 7 d. Zinc pyrithione was shown to be persistent in the experimental seawater in the short term. A basal level of ZnPT and ionized PT(-) was detected in the mussels, indicating that ZnPT availability in the sampling site is already high enough to induce a detectable accumulation in individuals of the native population. Zinc pyrithione rapidly accumulated in the tissues of the exposed mussels, proportionately to both exposure concentration and time, identifying the gills and digestive gland as important targets in the biological pathway of the contaminants. Even though the 7-d median lethal concentration (LC50) = 8.27 µM established here appears high with respect to reported ZnPT environmental concentrations, the results indicate that this biocide could represent a threat for marine organisms in coastal environments and that further investigations on its biological effects at sublethal doses are needed.

  13. Sensitivity of mottled sculpins (Cottus bairdi) and rainbow trout (Onchorhynchus mykiss) to acute and chronic toxicity of cadmium, copper, and zinc

    USGS Publications Warehouse

    Besser, John M.; Mebane, Christopher A.; Mount, David R.; Ivey, Chris D.; Kunz, James L.; Greer, I. Eugene; May, Thomas W.; Ingersoll, Christopher G.

    2007-01-01

    Studies of fish communities of streams draining mining areas suggest that sculpins (Cottus spp.) may be more sensitive than salmonids to adverse effects of metals. We compared the toxicity of zinc, copper, and cadmium to mottled sculpin (C. bairdi) and rainbow trout (Onchorhynchus mykiss) in laboratory toxicity tests. Acute (96-h) and early life-stage chronic (21- or 28-d) toxicity tests were conducted with rainbow trout and with mottled sculpins from populations in Minnesota and Missouri, USA, in diluted well water (hardness = 100 mg/L as CaCO3). Acute and chronic toxicity of metals to newly hatched and swim-up stages of mottled sculpins differed between the two source populations. Differences between populations were greatest for copper, with chronic toxicity values (ChV = geometric mean of lowest-observed-effect concentration and no-observed-effect concentration) of 4.4 μg/L for Missouri sculpins and 37 μg/L for Minnesota sculpins. Cadmium toxicity followed a similar trend, but differences between sculpin populations were less marked, with ChVs of 1.1 μg/L (Missouri) and 1.9 μg/L (Minnesota). Conversely, zinc was more toxic to Minnesota sculpins (ChV = 75 μg/L) than Missouri sculpins (chronic ChV = 219 μg/L). Species-average acute and chronic toxicity values for mottled sculpins were similar to or lower than those for rainbow trout and indicated that mottled sculpins were among the most sensitive aquatic species to toxicity of all three metals. Our results indicate that current acute and chronic water quality criteria for cadmium, copper, and zinc adequately protect rainbow trout but may not adequately protect some populations of mottled sculpins. Proposed water quality criteria for copper based on the biotic ligand model would be protective of both sculpin populations tested.

  14. Sensitivity of mottled sculpins (Cottus bairdi) and rainbow trout (Onchorhynchus mykiss) to acute and chronic toxicity of cadmium, copper, and zinc

    USGS Publications Warehouse

    Besser, J.M.; Mebane, C.A.; Mount, D.R.; Ivey, C.D.; Kunz, J.L.; Greer, I.E.; May, T.W.; Ingersoll, C.G.

    2007-01-01

    Studies of fish communities of streams draining mining areas suggest that sculpins (Cottus spp.) may be more sensitive than salmonids to adverse effects of metals. We compared the toxicity of zinc, copper, and cadmium to mottled sculpin (C. bairdi) and rainbow trout (Onchorhynchus mykiss) in laboratory toxicity tests. Acute (96-h) and early life-stage chronic (21- or 28-d) toxicity tests were conducted with rainbow trout and with mottled sculpins from populations in Minnesota and Missouri, USA, in diluted well water (hardness = 100 mg/L as CaCO3). Acute and chronic toxicity of metals to newly hatched and swim-up stages of mottled sculpins differed between the two source populations. Differences between populations were greatest for copper, with chronic toxicity values (ChV = geometric mean of lowest-observed-effect concentration and no-observed-effect concentration) of 4.4 ??g/L for Missouri sculpins and 37 ??g/L for Minnesota sculpins. Cadmium toxicity followed a similar trend, but differences between sculpin populations were less marked, with ChVs of 1.1 ??g/L (Missouri) and 1.9 ??g/L (Minnesota). Conversely, zinc was more toxic to Minnesota sculpins (ChV = 75 ??g/L) than Missouri sculpins (chronic ChV = 219 ??g/L). Species-average acute and chronic toxicity values for mottled sculpins were similar to or lower than those for rainbow trout and indicated that mottled sculpins were among the most sensitive aquatic species to toxicity of all three metals. Our results indicate that current acute and chronic water quality criteria for cadmium, copper, and zinc adequately protect rainbow trout but may not adequately protect some populations of mottled sculpins. Proposed water quality criteria for copper based on the biotic ligand model would be protective of both sculpin populations tested. ?? 2007 SETAC.

  15. Acute toxicity of cadmium, lead, zinc, and their mixtures to stream-resident fish and invertebrates.

    PubMed

    Mebane, Christopher A; Dillon, Frank S; Hennessy, Daniel P

    2012-06-01

    The authors conducted 150 tests of the acute toxicity of resident fish and invertebrates to Cd, Pb, and Zn, separately and in mixtures, in waters from the South Fork Coeur d'Alene River watershed, Idaho, USA. Field-collected shorthead sculpin (Cottus confusus), westslope cutthroat trout (Oncorhynchus clarkii lewisi), two mayflies (Baetis tricaudatus and Rhithrogena sp.), a stonefly (Sweltsa sp.), a caddisfly (Arctopsyche sp.), a snail (Gyraulus sp.), and hatchery rainbow trout (Oncorhynchus mykiss), were tested with all three metals. With Pb, the mayflies (Drunella sp., Epeorus sp., and Leptophlebiidae), a Simuliidae black fly, a Chironomidae midge, a Tipula sp. crane fly, a Dytiscidae beetle, and another snail (Physa sp.), were also tested. Adult westslope cutthroat trout were captured to establish a broodstock to provide fry of known ages for testing. With Cd, the range of 96-h median effect concentrations (EC50s) was 0.4 to >5,329 µg/L, and the relative resistances of taxa were westslope cutthroat trout ≈ rainbow trout ≈ sculpin < other taxa; with Pb, EC50s ranged from 47 to 3,323 µg/L, with westslope cutthroat trout < rainbow trout < other taxa; and with Zn, EC50s ranged from 21 to 3,704 µg/L, with rainbow trout < westslope cutthroat trout ≈ sculpin < other taxa. With swim-up trout fry, a pattern of decreasing resistance with increasing fish size was observed. In metal mixtures, the toxicities of the three metals were less than additive on a concentration-addition basis.

  16. Acute toxicity of cadmium, lead, zinc, and their mixtures to stream-resident fish and invertebrates

    USGS Publications Warehouse

    Mebane, Christopher A.; Dillon, Frank S.; Hennessy, Daniel P.

    2012-01-01

    The authors conducted 150 tests of the acute toxicity of resident fish and invertebrates to Cd, Pb, and Zn, separately and in mixtures, in waters from the South Fork Coeur d'Alene River watershed, Idaho, USA. Field-collected shorthead sculpin (Cottus confusus), westslope cutthroat trout (Oncorhynchus clarkii lewisi), two mayflies (Baetis tricaudatus and Rhithrogena sp.), a stonefly (Sweltsa sp.), a caddisfly (Arctopsyche sp.), a snail (Gyraulus sp.), and hatchery rainbow trout (Oncorhynchus mykiss), were tested with all three metals. With Pb, the mayflies (Drunella sp., Epeorus sp., and Leptophlebiidae), a Simuliidae black fly, a Chironomidae midge, a Tipula sp. crane fly, a Dytiscidae beetle, and another snail (Physa sp.), were also tested. Adult westslope cutthroat trout were captured to establish a broodstock to provide fry of known ages for testing. With Cd, the range of 96-h median effect concentrations (EC50s) was 0.4 to >5,329μg/L, and the relative resistances of taxa were westslope cutthroat trout ≈ rainbow trout ≈ sculpin << other taxa; with Pb, EC50s ranged from 47 to 3,323μg/L, with westslope cutthroat trout < rainbow trout < other taxa; and with Zn, EC50s ranged from 21 to 3,704μg/L, with rainbow trout < westslope cutthroat trout ≈ sculpin << other taxa. With swim-up trout fry, a pattern of decreasing resistance with increasing fish size was observed. In metal mixtures, the toxicities of the three metals were less than additive on a concentration-addition basis.

  17. Toxicity assessment of zinc oxide nanoparticles using sub-acute and sub-chronic murine inhalation models

    PubMed Central

    2014-01-01

    Background Although ZnO nanoparticles (NPs) are used in many commercial products and the potential for human exposure is increasing, few in vivo studies have addressed their possible toxic effects after inhalation. We sought to determine whether ZnO NPs induce pulmonary toxicity in mice following sub-acute or sub-chronic inhalation exposure to realistic exposure doses. Methods Mice (C57Bl/6) were exposed to well-characterized ZnO NPs (3.5 mg/m3, 4 hr/day) for 2 (sub-acute) or 13 (sub-chronic) weeks and necropsied immediately (0 wk) or 3 weeks (3 wks) post exposure. Toxicity was assessed by enumeration of total and differential cells, determination of total protein, lactate dehydrogenase activity and inflammatory cytokines in bronchoalveolar lavage (BAL) fluid as well as measurements of pulmonary mechanics. Generation of reactive oxygen species was assessed in the lungs. Lungs were evaluated for histopathologic changes and Zn content. Zn concentration in blood, liver, kidney, spleen, heart, brain and BAL fluid was measured. Results An elevated concentration of Zn2+ was detected in BAL fluid immediately after exposures, but returned to baseline levels 3 wks post exposure. Dissolution studies showed that ZnO NPs readily dissolved in artificial lysosomal fluid (pH 4.5), but formed aggregates and precipitates in artificial interstitial fluid (pH 7.4). Sub-acute exposure to ZnO NPs caused an increase of macrophages in BAL fluid and a moderate increase in IL-12(p40) and MIP-1α, but no other inflammatory or toxic responses were observed. Following both sub-acute and sub-chronic exposures, pulmonary mechanics were no different than sham-exposed animals. Conclusions Our ZnO NP inhalation studies showed minimal pulmonary inflammation, cytotoxicity or lung histopathologic changes. An elevated concentration of Zn in the lung and BAL fluid indicates dissolution of ZnO NPs in the respiratory system after inhalation. Exposure concentration, exposure mode and time post

  18. Acute toxicity of arsenobetaine

    SciTech Connect

    Kaise, T.; Watanabe, S.; Itoh, K.

    1985-01-01

    The acute toxicity of arsenobetaine was studied in male mice. No deaths were observed with oral administration of 10 g/kg of arsenobetaine. Therefore the LD/sub 50/ value was higher than 10 g/kg. This compound was found in urine in the non-metabolized form. No particular toxic symptoms were observed following administration. These suggest that arsenobetaine has low toxicity and is not metabolized in mice.

  19. Acute toxicity of cadmium, copper, zinc, ammonia, 3,3 prime -dichlorobenzidine, 2,6-dichloro-4-nitroaniline, methylene chloride, and 2,4,6-trichlorophenol to juvenile grass shrimp and killifish

    SciTech Connect

    Burton, D.T.; Fisher, D.J. )

    1990-05-01

    The acute toxicity of several compounds was investigated while performing a toxicity evaluation of a complex chemical effluent. The tests were conducted for one or more of the following reasons: (1) data were not available for the chemical; (2) data were not available for the species; or (3) data were not available for the juvenile life stage of the species. Forty-eight hour acute toxicity tests were run on juvenile grass shrimp (Palaemonetes pugio) and juvenile killifish (Fundulus heteroclitus) exposed to the following compounds: cadmium, copper, zinc, ammonia, 3,3{prime}-dichlorobenzidine, 2,6-dichloro-4-nitroaniline, methylene chloride (dichloromethane) and 2,4,6-trichlorophenol.

  20. Effect of age on acute toxicity of cadmium, copper, nickel, and zinc in individual-metal exposures to Daphnia magna neonates.

    PubMed

    Traudt, Elizabeth M; Ranville, James F; Meyer, Joseph S

    2017-01-01

    In previous studies, variability was high among replicate acute cadmium (Cd) Daphnia magna lethality tests (e.g., >10-fold range of median effect concentrations [EC50s]), less among zinc (Zn) tests, and relatively low for copper (Cu) and nickel (Ni) tests. Although the US Environmental Protection Agency's (USEPA's) protocol includes starting toxicity tests with neonates less than 24 h old, the authors hypothesized that age-related differences in sensitivity to metals might occur even within that relatively narrow age range. Daphnia magna neonates were collected during 3 age windows (0-4 h, 10-14 h, and 20-24 h old) and immediately exposed to each of the 4 metals for 48 h using the standard USEPA protocol. In repeated sets of tests during different weeks, the Cd EC50 of the youngest neonates was approximately 10-fold greater than the EC50 of the oldest neonates (i.e., Cd was less toxic to the youngest neonates) and the EC50 of neonates aged 10 h to 14 h was intermediate. Age-related differences were negligible in Cu, Ni, and Zn tests. Therefore, variability in toxicity of Cd may partly be caused by temporal variability in neonate age at the start of toxicity tests. Decreasing the age range of D. magna used in toxicity tests could help to improve the accuracy and precision of toxicity models, particularly for metal mixtures. Environ Toxicol Chem 2017;36:113-119. © 2016 SETAC.

  1. Sensitivity of early life stages of freshwater mussels (Unionidae) to acute and chronic toxicity of lead, cadmium, and zinc in water

    USGS Publications Warehouse

    Wang, N.; Ingersoll, C.G.; Ivey, C.D.; Hardesty, D.K.; May, T.W.; Augspurger, T.; Roberts, A.D.; Van Genderen, E.; Barnhart, M.C.

    2010-01-01

    Toxicity of lead, cadmium, or zinc to early life stages of freshwater mussels (fatmucket, Lampsilis siliquoidea; Neosho mucket, L. rafinesqueana) was evaluated in 48-h exposures with mussel larvae (glochidia), in 96-h exposures with newly transformed (5-d-old) and two- or six-month-old juvenile mussels, or in 28-d exposures with two- or four-month-old mussels in reconstituted soft water. The 24-h median effect concentrations (EC50s) for fatmucket glochidia (>299??g Pb/L, >227??g Cd/L, 2,685??g Zn/L) and 96-h EC50s for two- or six-month-old fatmucket (>426??g Pb/L, 199??g Cd/L, 1,700??g Zn/L) were much higher than 96-h EC50s for newly transformed fatmucket (142 and 298??g Pb/L, 16??g Cd/L, 151 and 175??g Zn/L) and Neosho mucket (188??g Pb/L, 20??g Cd/L, 145??g Zn/L). Chronic values for fatmucket were 10??g Pb/L, 6.0??g Cd/L, and 63 and 68??g Zn/L. When mussel data from the present study and the literature were included in updated databases for deriving U.S. Environmental Protection Agency water quality criteria, mussel genus mean acute values were in the lower percentiles of the sensitivity distribution of all freshwater species for Pb (the 26th percentile), Cd (the 15th to 29th percentile), or Zn (the 12th to 21st percentile). The mussel (Lampsilis) genus mean chronic value was the lowest value ever reported for Pb (the 9th percentile) but was near the middle of the sensitivity distribution for Cd (the 61st percentile) or Zn (the 44th percentile). These results indicate that mussels were relatively sensitive to the acute toxicity of these three metals and to the chronic toxicity of Pb, but were moderately sensitive to the chronic toxicity of Cd or Zn compared to other freshwater species. ?? 2010 SETAC.

  2. Acute toxicity of chromate, DDT, PCP, TPBS, and zinc to Daphnia magna cultured in hard and soft water

    SciTech Connect

    Berglind, R.; Dave, G.

    1984-07-01

    The aim of this study was to compare the toxicity of five chemicals to water fleas (Daphnia magna) cultured in either hard to soft water. The toxicity tests were made in reconstituted waters and the five chemicals to be tested were, p,p'-DDT, pentachlorophenol (PCP), tetrapropylenbenzyl sulfonate (TPBS), potassium bichromate (K/sub 2/Cr/sub 2/O/sub 7/) and zincsulfate (ZnSO/sub 4/ x 7H/sub 2/O).

  3. [An atypical case of acute zinc poisoning].

    PubMed

    Andrzejak, R; Antonowicz, J; Andreasik, Z

    1992-01-01

    The paper discussed a case of acute zinc intoxication in a 48-year old welder, after four days of cutting zinc-plated pipes with an oxy-acetylene torch, in poorly ventilated places. The zinc fever has been diagnosed on the basis of the symptoms and confirmed by laboratory findings: high zinc blood and erythrocyte concentration and increased urinary excretion of zinc. One year the intoxication the manifestations of the psycho-organic syndrome with predilection to pseudoneurotic reactions were still present. The non-standard factor in this case is the very short time of exposure to zinc oxide and the occurrence of chronic encephalopathy is also singular.

  4. Acute toxicity of copper, lead, cadmium, and zinc to early life stages of white sturgeon (Acipenser transmontanus) in laboratory and Columbia River water.

    PubMed

    Vardy, David W; Santore, Robert; Ryan, Adam; Giesy, John P; Hecker, Markus

    2014-01-01

    Populations of white sturgeon (Acipenser transmontanus) are in decline in North America. This is attributed, primarily, to poor recruitment, and white sturgeon are listed as threatened or endangered in several parts of British Columbia, Canada, and the United States. In the Columbia River, effects of metals have been hypothesized as possible contributing factors. Previous work has demonstrated that early life stage white sturgeon are particularly sensitive to certain metals, and concerns over the level of protectiveness of water quality standards are justified. Here we report results from acute (96-h) toxicity tests for copper (Cu), cadmium (Cd), zinc (Zn), and lead (Pb) from parallel studies that were conducted in laboratory water and in the field with Columbia River water. Water effect ratios (WERs) and sensitivity parameters (i.e., median lethal accumulations, or LA50s) were calculated to assess relative bioavailability of these metals in Columbia River water compared to laboratory water, and to elucidate possible differences in sensitivity of early life stage white sturgeon to the same concentrations of metals when tested in the different water sources. For Cu and Pb, white sturgeon toxicity tests were initiated at two life stages, 8 and 40 days post-hatch (dph), and median lethal concentrations (LC50s) ranged between 9-25 μg Cu/L and 177-1,556 μg Pb/L. LC50s for 8 dph white sturgeon exposed to Cd in laboratory water and river water were 14.5 and 72 μg/L, respectively. Exposure of 8 dph white sturgeon to Zn in laboratory and river water resulted in LC50s of 150 and 625 μg/L, respectively. Threshold concentrations were consistently less in laboratory water compared with river water, and as a result, WERs were greater than 1 in all cases. In addition, LA50s were consistently greater in river water exposures compared with laboratory exposures in all paired tests. These results, in combination with results from the biotic ligand model, suggest that the observed

  5. Zinc.

    PubMed

    Barceloux, D G

    1999-01-01

    The use of zinc in metal alloys and medicinal lotions dates back before the time of Christ. Currently, most of the commercial production of zinc involves the galvanizing of iron and the manufacture of brass. Some studies support the use of zinc gluconate lozenges to treat the common cold, but there are insufficient data at this time to recommend the routine use of these lozenges. Zinc is an essential co-factor in a variety of cellular processes including DNA synthesis, behavioral responses, reproduction, bone formation, growth, and wound healing. Zinc is a relatively common metal with an average concentration of 50 mg/kg soil and a range of 10-300 mg/kg soil. Meat, seafood, dairy products, nuts, legumes, and whole grains contain relatively high concentrations of zinc. The mobility of zinc in anaerobic environments is poor and therefore severe zinc contamination occurs primarily near points sources of zinc release. The recommended daily allowance for adults is 15 mg zinc. The ingestion of 1-2 g zinc sulfate produces emesis. Zinc compounds can produce irritation and corrosion of the gastrointestinal tract, along with acute renal tubular necrosis and interstitial nephritis. Inhalation of high concentrations of zinc chloride from smoke bombs detonated in closed spaces may cause chemical pneumonitis and adult respiratory distress syndrome. In the occupational setting inhalation of fumes from zinc oxide is the most common cause of metal fume fever (fatigue, chills, fever, myalgias, cough, dyspnea, leukocytosis, thirst, metallic taste, salivation). Zinc compounds are not suspected carcinogens. Treatment of zinc toxicity is supportive. Calcium disodium ethylenediaminetetraacetate (CaNa2EDTA) is the chelator of choice based on case reports that demonstrate normalization of zinc concentrations, but there are few clinical data to confirm the efficacy of this agent.

  6. Acute toxicity of ingested fluoride.

    PubMed

    Whitford, Gary Milton

    2011-01-01

    This chapter discusses the characteristics and treatment of acute fluoride toxicity as well as the most common sources of overexposure, the doses that cause acute toxicity, and factors that can influence the clinical outcome. Cases of serious systemic toxicity and fatalities due to acute exposures are now rare, but overexposures causing toxic signs and symptoms are not. The clinical course of systemic toxicity from ingested fluoride begins with gastric signs and symptoms, and can develop with alarming rapidity. Treatment involves minimizing absorption by administering a solution containing calcium, monitoring and managing plasma calcium and potassium concentrations, acid-base status, and supporting vital functions. Approximately 30,000 calls to US poison control centers concerning acute exposures in children are made each year, most of which involve temporary gastrointestinal effects, but others require medical treatment. The most common sources of acute overexposures today are dental products - particularly dentifrices because of their relatively high fluoride concentrations, pleasant flavors, and their presence in non-secure locations in most homes. For example, ingestion of only 1.8 ounces of a standard fluoridated dentifrice (900-1,100 mg/kg) by a 10-kg child delivers enough fluoride to reach the 'probably toxic dose' (5 mg/kg body weight). Factors that may influence the clinical course of an overexposure include the chemical compound (e.g. NaF, MFP, etc.), the age and acid-base status of the individual, and the elapsed time between exposure and the initiation of treatment. While fluoride has well-established beneficial dental effects and cases of serious toxicity are now rare, the potential for toxicity requires that fluoride-containing materials be handled and stored with the respect they deserve.

  7. Diphacinone and zinc phosphide toxicity in a flock of Peafowl.

    PubMed

    Shivaprasad, H L; Galey, F

    2001-12-01

    Toxicity probably due to a combination of diphacinone and zinc phosphide was diagnosed in a flock of peafowl, in which 35 birds in a flock of 80 died over a span of 10 days without any apparent clinical signs. Chickens and guinea fowl, 30 each on the same premises, were not affected. Plastic tubes containing diphacinone and zinc phosphide were used on the premises to control ground squirrels. Most of the six dead peafowl, which ranged in age from 6 months to 4 years, had an accumulation of serosanguinous fluid in the abdominal cavity, semi-clotted blood over the liver lobes, increased pericardial fluid, and enlarged and pale kidneys. Pellets of diphacinone and zinc phosphide were found in the crop and gizzard contents from most of the birds. Microscopically, most of the birds had mild to moderate centrolobular degeneration of hepatocytes and multifocal degeneration of myofibres in the heart with infiltration by a few mononuclear cells. Acute nephrosis and mucosal oedema in the oesophagus and crop were also observed. Toxicological analysis of the crop and gizzard contents revealed the presence of diphacinone and phosphine gas, and analysis of the crop contents from two birds for heavy metals revealed zinc levels of up to 6600 parts/10 6 . It was suspected that only the peafowl and not the chickens and guinea fowl were affected because peafowl, with their longer necks, were able to reach into the plastic tubes and eat the pellets.

  8. Histidine Protects Against Zinc and Nickel Toxicity in Caenorhabditis elegans

    PubMed Central

    Murphy, John T.; Bruinsma, Janelle J.; Schneider, Daniel L.; Collier, Sara; Guthrie, James; Chinwalla, Asif; Robertson, J. David; Mardis, Elaine R.; Kornfeld, Kerry

    2011-01-01

    Zinc is an essential trace element involved in a wide range of biological processes and human diseases. Zinc excess is deleterious, and animals require mechanisms to protect against zinc toxicity. To identify genes that modulate zinc tolerance, we performed a forward genetic screen for Caenorhabditis elegans mutants that were resistant to zinc toxicity. Here we demonstrate that mutations of the C. elegans histidine ammonia lyase (haly-1) gene promote zinc tolerance. C. elegans haly-1 encodes a protein that is homologous to vertebrate HAL, an enzyme that converts histidine to urocanic acid. haly-1 mutant animals displayed elevated levels of histidine, indicating that C. elegans HALY-1 protein is an enzyme involved in histidine catabolism. These results suggest the model that elevated histidine chelates zinc and thereby reduces zinc toxicity. Supporting this hypothesis, we demonstrated that dietary histidine promotes zinc tolerance. Nickel is another metal that binds histidine with high affinity. We demonstrated that haly-1 mutant animals are resistant to nickel toxicity and dietary histidine promotes nickel tolerance in wild-type animals. These studies identify a novel role for haly-1 and histidine in zinc metabolism and may be relevant for other animals. PMID:21455490

  9. Acute and chronic arsenic toxicity

    PubMed Central

    Ratnaike, R

    2003-01-01

    Arsenic toxicity is a global health problem affecting many millions of people. Contamination is caused by arsenic from natural geological sources leaching into aquifers, contaminating drinking water and may also occur from mining and other industrial processes. Arsenic is present as a contaminant in many traditional remedies. Arsenic trioxide is now used to treat acute promyelocytic leukaemia. Absorption occurs predominantly from ingestion from the small intestine, though minimal absorption occurs from skin contact and inhalation. Arsenic exerts its toxicity by inactivating up to 200 enzymes, especially those involved in cellular energy pathways and DNA synthesis and repair. Acute arsenic poisoning is associated initially with nausea, vomiting, abdominal pain, and severe diarrhoea. Encephalopathy and peripheral neuropathy are reported. Chronic arsenic toxicity results in multisystem disease. Arsenic is a well documented human carcinogen affecting numerous organs. There are no evidence based treatment regimens to treat chronic arsenic poisoning but antioxidants have been advocated, though benefit is not proven. The focus of management is to reduce arsenic ingestion from drinking water and there is increasing emphasis on using alternative supplies of water. PMID:12897217

  10. Acute copper toxicity following copper glycinate injection.

    PubMed

    Oon, S; Yap, C-H; Ihle, B U

    2006-11-01

    We present a patient who developed multi-organ failure due to severe copper toxicity following attempted suicide by s.c. injection of copper glycinate. Acute copper toxicity is rare in the developed world, although it occurs more frequently in developing world countries, where it is a common mode of suicide. Acute toxicity usually results from oral ingestion and there are several local and systemic effects. Specific management can be difficult as there is little evidence regarding the efficacy of chelating agents in acute toxicity.

  11. Alternative acute oral toxicity assessment under REACH based on sub-acute toxicity values.

    PubMed

    Gissi, Andrea; Louekari, Kimmo; Hoffstadt, Laurence; Bornatowicz, Norbert; Aparicio, Alberto Martin

    2016-11-08

    The REACH Regulation requires information on acute oral toxicity for substances produced or imported in quantities greater than one tonne per year. When registering, animal testing should be used as last resort. The standard acute oral toxicity test requires use of animals. Therefore, the European Chemicals Agency examined whether alternative ways exist to generate information on acute oral toxicity. The starting hypothesis was that low acute oral toxicity can be predicted from the results of low toxicity in oral sub-acute toxicity studies. Proving this hypothesis would allow avoiding acute toxicity oral testing whenever a sub-acute oral toxicity study is required or available and indicates low toxicity. ECHA conducted an analysis of the REACH database and found suitable studies on both acute oral and sub-acute oral toxicities for 1,256 substances. 415 of these substances had low toxicity in the sub-acute toxicity study (i.e. NO(A)EL at or above the classification threshold of 1,000 mg/kg). For 98% of these substances, low acute oral toxicity was also reported (i.e. LD₅₀ above the classification threshold of 2,000 mg/kg). On the other hand, no correlation was found between lower NO(A)ELs and LD₅₀. According to the REACH regulation, this approach for predicting acute oral toxicity needs to be considered as part of a weight of evidence analysis. Therefore, additional sources of information to support this approach are presented. Ahead of the last REACH registration deadline in 2018, ECHA estimates that registrants of about 550 substances can omit the in vivo acute oral study by using this adaptation.

  12. Chronic toxicity of mixtures of copper, cadmium and zinc to Daphnia pulex

    SciTech Connect

    Flickinger, A.L.

    1984-01-01

    Daphnia pulex (de Greer) were exposed to single and bimetal mixtures of copper, cadmium and zinc in reconstituted waters of different hardness/alkalinity and humic acid concentrations. The effect of single and bimetal exposure to these metals was evaluated by survivorship and reproductive indices of brood size, percent aborted eggs/brood, age at reproductive maturity, age at first reproduction and the instantaneous rate of population growth. Accumulation by 7-day-old Daphnia magna of metals in these mixtures was also assessed in medium water containing 0.0 and 0.75 mg humic acid/L. The addition of 0.75 mg humic acid/L decreased the acute toxicity of copper and zinc but increased the acute toxicity of cadmium. Survival was the best index of a single or bimetal chronic stress since it was equally or more sensitive than any reproductive index. The interaction between copper and zinc was variable in soft water which contained 0.15 mg humic acid/L, but largely independent in medium water which contained 0.0 and 0.75 mg humic acid/L. Zinc and humic acid had no effect on the accumulation of copper in medium water. Copper and cadmium were synergistic in their interaction on daphniid survival in medium water which contained 0.0 and 0.75 mg humic acid/L.

  13. Acute aquatic toxicity of biodiesel fuels

    SciTech Connect

    Wright, B.; Haws, R.; Little, D.; Reese, D.; Peterson, C.; Moeller, G.

    1995-12-31

    This study develops data on the acute aquatic toxicity of selected biodiesel fuels which may become subject to environmental effects test regulations under the US Toxic Substances Control Act (TSCA). The test substances are Rape Methyl Ester (RME), Rape Ethyl Ester (REE), Methyl Soyate (MS), a biodiesel mixture of 20% REE and 80% Diesel, a biodiesel mixture of 50% REE and diesel, and a reference substance of Phillips D-2 Reference Diesel. The test procedure follows the Daphnid Acute Toxicity Test outlined in 40 CFR {section} 797.1300 of the TSCA regulations. Daphnia Magna are exposed to the test substance in a flow-through system consisting of a mixing chamber, a proportional diluter, and duplicate test chambers. Novel system modifications are described that accommodate the testing of oil-based test substances with Daphnia. The acute aquatic toxicity is estimated by an EC50, an effective concentration producing immobility in 50% of the test specimen.

  14. Acute toxicity of gasoline and some additives.

    PubMed Central

    Reese, E; Kimbrough, R D

    1993-01-01

    The acute toxicity of gasoline; its components benzene, toluene, and xylene; and the additives ethanol, methanol, and methyl tertiary butyl ether are reviewed. All of these chemicals are only moderately to mildly toxic at acute doses. Because of their volatility, these compounds are not extensively absorbed dermally unless the exposed skin is occluded. Absorption through the lungs and the gastrointestinal tract is quite efficient. After ingestion, the principal danger for a number of these chemicals, particularly gasoline, is aspiration pneumonia, which occurs mainly in children. It is currently not clear whether aspiration pneumonia would still be a problem if gasoline were diluted with ethanol or methanol. During the normal use of gasoline or mixtures of gasoline and the other solvents as a fuel, exposures would be much lower than the doses that have resulted in poisoning. No acute toxic health effects would occur during the normal course of using automotive fuels. PMID:8020435

  15. Acute toxicity of gasoline and some additives

    SciTech Connect

    Reese, E.; Kimbrough, R.D.

    1993-12-01

    The acute toxicity of gasoline; its components benzene, toluene, and xylene; and the additives ethanol, methanol, and methyl tertiary butyl ether are reviewed. All of these chemicals are only moderately to mildly toxic at acute doses. Because of their volatility, these compounds are not extensively absorbed dermally unless the exposed skin is occluded. Absorption through the lungs and the gastrointestinal tract is quite efficient. After ingestion, the principal danger for a number of these chemicals, particularly gasoline, is aspiration pneumonia, which occurs mainly in children. It is currently not clear whether aspiration pneumonia would still be a problem if gasoline were diluted with ethanol or methanol. During the normal use of gasoline or mixtures of gasoline and the other solvents as a fuel, exposures would be much lower than the doses that have resulted in poisoning. No acute toxic health effects would occur during the normal course of using automotive fuels. 128 refs., 7 tabs.

  16. Copper toxicity and copper-zinc interactions in amphibian embryos.

    PubMed

    Herkovits, J; Helguero, L A

    1998-09-29

    The copper hazard was evaluated by means of a 7-day toxicity test with Bufo arenarum embryos. The LC50 and LC10 values from 24 to 168 h of exposure were approx. 0.085 and 0.05 mg Cu2+/1, respectively, while the LC90 resulted in 0.155 mg Cu2+/1 but in this case from 96 h onwards the LC90 diminished up to approx. 0.105 mg Cu2+/1. These data plotted as Toxicity Profiles (TOP) provide a better understanding of concentration and time-dependent thresholds. For instance, exposure threshold occurs within the first 24 h of treatment while for concentration thresholds LC10 and LC90 seem to be more meaningful than LC50 because the S.D. of this last value is overlapping those of LC10 and LC90 for most of the exposure period evaluated. Toxicity data corresponds to a pH of 6.8 which is normal for the maintaining media. Combined treatments of copper and zinc point out a beneficial effect of zinc proportional to the zinc concentration in the maintaining media, e.g. 100% of protection was achieved with 30 mg Zn2+/1 for a copper concentration exerting 90% of mortality. The presence of Cu2+ did not enhance Zn2+ toxicity. The results are discussed in terms of water quality criteria for wildlife and human health protection purposes.

  17. Developmental toxicity of intravenously injected zinc oxide nanoparticles in rats.

    PubMed

    Lee, Jinsoo; Yu, Wook-Joon; Song, Jeongah; Sung, Changhyun; Jeong, Eun Ju; Han, Ji-Seok; Kim, Pilje; Jo, Eunhye; Eom, Ikchun; Kim, Hyun-Mi; Kwon, Jung-Taek; Choi, Kyunghee; Choi, Jonghye; Kim, Heyjin; Lee, Handule; Park, Juyoung; Jin, Seon Mi; Park, Kwangsik

    2016-12-01

    Recent toxicity studies of zinc oxide nanoparticles by oral administration showed relatively low toxicity, which may be resulted from low bioavailability. So, the intrinsic toxicity of zinc oxide nanoparticles needs to be evaluated in the target organs by intravenous injection for full systemic concentration of the administered dosage. Although the exposure chance of injection route is low compared to oral and/or inhalation route, it is important to see the toxicity with different exposure routes to get better risk management tool. In this study, the effects of zinc oxide nanoparticles on dams and fetuses were investigated in rats after intravenous injection (5, 10, and 20 mg/kg) from gestation day 6 to 20. Two of 20 dams in the 20 mg/kg treatment group died during the treatment period. Hematological examination and serum biochemistry showed dose-dependent toxicity in treated dams. Histopathological analysis of treated dams revealed multifocal mixed cell infiltration and thrombosis in lung, tubular dilation in kidneys, and extramedullary hemopoiesis in liver. Total dead fetuses (post-implantation loss) were increased and the body weight of fetus was decreased in the 20 mg/kg treatment group. Statistical differences in corpora lutea, resorption, placental weight, morphological alterations including external, visceral and skeletal malformations were not observed in treated groups. Based on the data, lowest observed adverse effect level of injection route was suggested to be 5 mg/kg in dams and no observed adverse effect level was suggested to be 10 mg/kg in fetal developmental toxicity.

  18. [An acute toxicity study of bromantane].

    PubMed

    Bugaeva, L I; Verovskiĭ, V E; Iezhitsa, I N; Spasov, A A

    2000-01-01

    The toxicity of bromantan was evaluated by conventional acute tests (according to Belen'kiĭ) and by the behavioral activity data (according to Irvin). A method of integral graphical representation of the behavioral activity data is suggested, according to which the results are plotted as a "dose trajectory." Using the dose trajectory constructed for bromantan, the levels of therapeutic, toxic, and lethal doses were calculated. It was established that catecholaminergic effects account for the mechanism of therapeutic action of bromantan, while cholinergic effects determine the drug action in toxic doses.

  19. Olanzapine overdose presenting with acute muscle toxicity

    PubMed Central

    Keyal, Niraj; Shrestha, Gentle Sunder; Pradhan, Saurabh; Maharjan, Ramesh; Acharya, Subhash Prasad; Marhatta, Moda Nath

    2017-01-01

    Olanzapine is an atypical antipsychotic drug that is being increasingly used as an intentional overdose. It usually presents with reduced and fluctuating level of consciousness and coma. It may rarely present with muscle toxicity by binding to HT2A receptor in skeletal muscle and increasing its permeability. We report a case of such poisoning which had no obvious symptoms but was brought to emergency due to overdose and was found to have acute muscle toxicity as evidenced by raised creatine phosphokinase (CPK) levels. From this, we also want to emphasize that CPK levels should be checked in all the patient's prescribed olanzapine to look for muscle toxicity.

  20. Influence of temperature on the toxicity of zinc to the earthworm Eisenia fetida

    SciTech Connect

    Spurgeon, D.J.; Tomlin, M.A.; Hopkin, S.P.

    1997-02-01

    A range of toxicity tests have been proposed to assess the potential hazards of pollutants to earthworms. Of these, the two acute toxicity tests using Eisenia fetida recommended by the OECD and EEC have become routinely used in the risk assessment and regulation of new and existing chemicals. In addition to the acute tests, procedures have also been proposed for measuring the sub-lethal effects of chemicals on parameter such as reproduction and weight change. In both the lethal and sub-lethal toxicity tests developed with worms, attempts have been made to standardise test conditions to allow results from different laboratories to be directly compared. However, variability in exposure conditions and responses are fundamental to determine the effects of pollutants under natural conditions. In the field, conditions such as light, moisture availability, pH, temperature and humidity all fluctuate over time. Such variations affect both the sensitivity and exposure of individuals to toxic chemicals. Hence when evaluating the potential effects of pollutants, it may be important to known how changes in test conditions influence toxicity. This study assessed the effects of different temperatures on the lethal and sub-lethal toxicity of zinc for the earthworm Eisenia fetida. 23 refs., 1 fig., 1 tab.

  1. CDP-choline: acute toxicity study.

    PubMed

    Grau, T; Romero, A; Sacristán, A; Ortiz, J A

    1983-01-01

    The acute toxicity of a single dose of cytidine diphosphate choline (CDP-choline, citicoline, Somazina) by different administration routes in mice and rats has been studied. LD50 values were determined according to the cumulative method by Reed-Muench for mortality rate, and Pizzi's method for calculation of standard error.

  2. Consensus Modeling of Oral Rat Acute Toxicity

    EPA Science Inventory

    An acute toxicity dataset (oral rat LD50) with about 7400 compounds was compiled from the ChemIDplus database. This dataset was divided into a modeling set and a prediction set. The compounds in the prediction set were selected so that they were present in the modeling set used...

  3. Assessment of the Mitigative Capacity of Dietary Zinc on PCB126 Hepatotoxicity and the Contribution of Zinc to Toxicity.

    PubMed

    Klaren, William D; Gibson-Corley, Katherine N; Wels, Brian; Simmons, Donald L; McCormick, Michael L; Spitz, Douglas R; Robertson, Larry W

    2016-05-16

    Hepatic levels of the essential micronutrient, zinc, are diminished by several hepatotoxicants, and the dietary supplementation of zinc has proven protective in those cases. 3,3',4,4',5-Pentachlorobiphenyl (PCB126), a liver toxicant, alters hepatic nutrient homeostasis and lowers hepatic zinc levels. The current study was designed to determine the mitigative potential of dietary zinc in the toxicity associated with PCB126 and the role of zinc in that toxicity. Male Sprague-Dawley rats were divided into three dietary groups and fed diets deficient in zinc (7 ppm Zn), adequate in zinc (30 ppm Zn), and supplemented in zinc (300 ppm). The animals were maintained for 3 weeks on these diets, then given a single IP injection of vehicle or 1 or 5 μmol/kg PCB126. After 2 weeks, the animals were euthanized. Dietary zinc increased the level of ROS, the activity of CuZnSOD, and the expression of metallothionein but decreased the levels of hepatic manganese. PCB126 exposed rats exhibited classic signs of exposure, including hepatomegaly, increased hepatic lipids, increased ROS and CYP induction. Liver histology suggests some mild ameliorative properties of both zinc deficiency and zinc supplementation. Other metrics of toxicity (relative liver and thymus weights, hepatic lipids, and hepatic ROS) did not support this trend. Interestingly, the zinc supplemented high dose PCB126 group had mildly improved histology and less efficacious induction of investigated genes than did the low dose PCB126 group. Overall, decreases in zinc caused by PCB126 likely contribute little to the ongoing toxicity, and the mitigative/preventive capacity of zinc against PCB126 exposure seems limited.

  4. Acute methanol toxicity in minipigs

    SciTech Connect

    Dorman, D.C.; Dye, J.A.; Nassise, M.P.; Ekuta, J.; Bolon, B.

    1993-01-01

    The pig has been proposed as a potential animal model for methanol-induced neuro-ocular toxicosis in humans because of its low liver tetrahydrofolate levels and slower rate of formate metabolism compared to those of humans. To examine the validity of this animal model, 12 4-month-old female minipigs (minipig YU) were given a single oral dose of water or methanol at 1.0, 2.5, or 5.0 g/kg body wt by gavage (n = 3 pigs/dose). Dose-dependent signs of acute methanol intoxication, which included mild CNS depression, tremors, ataxia, and recumbency, developed within 0.5 to 2.0 hr, and resolved by 52 hr. Methanol- and formate-dosed pigs did not develop optic nerve lesions, toxicologically significant formate accumulation, or metabolic acidosis. Based on results following a single dose, female minipigs do not appear to be overtly sensitive to methanol and thus may not be a suitable animal model for acute methanol-induced neuroocular toxicosis.

  5. Quantification of zinc toxicity using neuronal networks on microelectrode arrays.

    PubMed

    Parviz, M; Gross, G W

    2007-05-01

    Murine neuronal networks, derived from embryonic frontal cortex (FC) tissue grown on microelectrode arrays, were used to investigate zinc toxicity at concentrations ranging from 20 to 2000 microM total zinc acetate added to the culture medium. Continual multi-channel recording of spontaneous action potential generation allowed a quantitative analysis of the temporal evolution of network spike activity generation at specific zinc acetate concentrations. Cultures responded with immediate concentration-dependent excitation lasting from 5 to 50 min and consisting of increased spiking and enhanced, coordinated bursting, followed by irreversible activity decay. The time to 50% and 90% activity loss was concentration dependent, highly reproducible, and formed linear functions in log-log plots. Above 100 microM total zinc acetate, the activity loss was associated with massive cell swelling, blebbing, and even vigorous neuronal cell lysing. Glia showed stress, but did not participate in the extensive cell swelling. Network activity loss generally preceded morphological changes. Cultures pretreated with the GABA(A) receptor antagonists bicuculline (40 microM) and picrotoxin (1mM) lacked the initial excitation phase. This suggests that zinc-induced excitation may be mediated by interfering with GABA inhibition. Partial network protection was achieved by stopping spontaneous activity with either tetrodotoxin (200 nM) or lidocaine (250 microM). However, recovery was not complete and slow deterioration of network activity continued over 6-h periods. Removal of zinc by early medium changes showed irreversible, catastrophic network failure to develop in a concentration-dependent time window between 50% and 90% activity loss.

  6. Acute aquatic toxicity of alkyl phenol ethoxylates

    SciTech Connect

    Schueuermann G2 )

    1991-04-01

    The recently derived log Kow (octanol/water partition coefficient in logarithmic form) increment for a nonterminal oxyethylene unit was used to calculate a quantitative structure-activity relationships for literature data on the acute crustacean toxicity of polyoxyethylene surfactants. The resulting log Kow regression parameters are between the corresponding values for nonpolar and polar narcosis, which supports an interpretation of the surfactants' aquatic toxicity on the basis of another distinct mode of action. Furthermore, a comparison with calculated water solubility data indicates that for log Kow greater than 5 an aquatic toxicity decrease due to a solubility limit is expected, which gets support from two other sets on toxicity data of nonyl phenol polyethoxylates.

  7. Metallothionein-induced zinc partitioning exacerbates hyperoxic acute lung injury

    PubMed Central

    Lee, Sang-Min; McLaughlin, Joseph N.; Frederick, Daniel R.; Zhu, Lin; Thambiayya, Kalidasan; Wasserloos, Karla J.; Kaminski, Iris; Pearce, Linda L.; Peterson, Jim; Li, Jin; Latoche, Joseph D.; Peck Palmer, Octavia M.; Stolz, Donna Beer; Fattman, Cheryl L.; Alcorn, John F.; Oury, Tim D.; Angus, Derek C.; Pitt, Bruce R.

    2013-01-01

    Hypozincemia, with hepatic zinc accumulation at the expense of other organs, occurs in infection, inflammation, and aseptic lung injury. Mechanisms underlying zinc partitioning or its impact on extrahepatic organs are unclear. Here we show that the major zinc-binding protein, metallothionein (MT), is critical for zinc transmigration from lung to liver during hyperoxia and preservation of intrapulmonary zinc during hyperoxia is associated with an injury-resistant phenotype in MT-null mice. Particularly, lung-to-liver zinc ratios decreased in wild-type (WT) and increased significantly in MT-null mice breathing 95% oxygen for 72 h. Compared with female adult WT mice, MT-null mice were significantly protected against hyperoxic lung injury indicated by reduced inflammation and interstitial edema, fewer necrotic changes to distal airway epithelium, and sustained lung function at 72 h hyperoxia. Lungs of MT-null mice showed decreased levels of immunoreactive LC3, an autophagy marker, compared with WT mice. Analysis of superoxide dismutase (SOD) activity in the lungs revealed similar levels of manganese-SOD activity between strains under normoxia and hyperoxia. Lung extracellular SOD activity decreased significantly in both strains at 72 h of hyperoxia, although there was no difference between strains. Copper-zinc-SOD activity was ∼4× higher under normoxic conditions in MT-null compared with WT mice but was not affected in either group by hyperoxia. Collectively the data suggest that genetic deletion of MT-I/II in mice is associated with compensatory increase in copper-zinc-SOD activity, prevention of hyperoxia-induced zinc transmigration from lung to liver, and hyperoxia-resistant phenotype strongly associated with differences in zinc homeostasis during hyperoxic acute lung injury. PMID:23275622

  8. Acute toxicity of gymnodimine to mice.

    PubMed

    Munday, Rex; Towers, Neale R; Mackenzie, Lincoln; Beuzenberg, Veronica; Holland, Patrick T; Miles, Christopher O

    2004-08-01

    The acute toxicity of the phycotoxin gymnodimine to female Swiss mice by intraperitoneal injection and by oral administration has been determined. Gymnodimine was highly toxic by injection, the LD50 being only 96 microg/kg. Animals either died within 10 min of injection or made a full recovery with no perceptible long-term effects. Gymnodimine was also toxic after oral administration by gavage (LD50 755 microg/kg), but was much less toxic when administered with food. No signs of toxicity were seen in mice voluntarily ingesting food containing gymnodimine at a level sufficient to give a dose of approximately 7500 microg/kg. Pre-treatment with physostigmine or neostigmine protected against injected gymnodimine, suggesting that the latter exerts its toxic effects via blockade of nicotinic receptors at the neuromuscular junction. The low toxicity of gymnodimine when ingested with food suggests that this compound is of low risk to humans, a conclusion that is consonant with anecdotal evidence for the absence of harmful effects in individuals consuming shellfish contaminated with gymnodimine.

  9. Acute inhalation toxicity of carbonyl sulfide

    SciTech Connect

    Benson, J.M.; Hahn, F.F.; Barr, E.B.

    1995-12-01

    Carbonyl sulfide (COS), a colorless gas, is a side product of industrial procedures sure as coal hydrogenation and gasification. It is structurally related to and is a metabolite of carbon disulfide. COS is metabolized in the body by carbonic anhydrase to hydrogen sulfide (H{sub 2}S), which is thought to be responsible for COS toxicity. No threshold limit value for COS has been established. Results of these studies indicate COS (with an LC{sub 50} of 590 ppm) is slightly less acutely toxic than H{sub 2}S (LC{sub 50} of 440 ppm).

  10. Acute toxicity from baking soda ingestion.

    PubMed

    Thomas, S H; Stone, C K

    1994-01-01

    Sodium bicarbonate is an extremely well-known agent that historically has been used for a variety of medical conditions. Despite the widespread use of oral bicarbonate, little documented toxicity has occurred, and the emergency medicine literature contains no reports of toxicity caused by the ingestion of baking soda. Risks of acute and chronic oral bicarbonate ingestion include metabolic alkalosis, hypernatremia, hypertension, gastric rupture, hyporeninemia, hypokalemia, hypochloremia, intravascular volume depletion, and urinary alkalinization. Abrupt cessation of chronic excessive bicarbonate ingestion may result in hyperkalemia, hypoaldosteronism, volume contraction, and disruption of calcium and phosphorus metabolism. The case of a patient with three hospital admissions in 4 months, all the result of excessive oral intake of bicarbonate for symptomatic relief of dyspepsia is reported. Evaluation and treatment of patients with acute bicarbonate ingestion is discussed.

  11. Role of biogenic sulfide in attenuating zinc oxide and copper nanoparticle toxicity to acetoclastic methanogenesis.

    PubMed

    Gonzalez-Estrella, Jorge; Puyol, Daniel; Sierra-Alvarez, Reyes; Field, Jim A

    2015-01-01

    Soluble ions released by zinc oxide (ZnO) and copper (Cu(0)) nanoparticles (NPs) have been associated with toxicity to methanogens. This study evaluated the role of biogenic sulfide in attenuating ZnO and Cu(0) NP toxicity to methanogens. Short- and long-term batch experiments were conducted to explore ZnO and Cu(0) NPs toxicity to acetoclastic methanogens in sulfate-containing (0.4mM) and sulfate-free conditions. ZnO and Cu(0) were respectively 14 and 7-fold less toxic in sulfate-containing than in sulfate-free assays as indicated by inhibitory constants (Ki). The Ki with respect to residual soluble metal indicated that soluble metal was well correlated with toxicity irrespective of the metal ion source or presence of biogenic sulfide. Long-term assays indicated that ZnO and Cu(0) NPs caused different effects on methanogens. ZnO NPs without protection of sulfide caused a chronic effect, whereas Cu(0) NPs caused an acute effect and recovered. This study confirms that biogenic sulfide effectively attenuates ZnO and Cu(0) NPs toxicity to methanogens by the formation of metal sulfides.

  12. Zinc causes acute impairment of glutathione metabolism followed by coordinated antioxidant defenses amplification in gills of brown mussels Perna perna.

    PubMed

    Trevisan, Rafael; Flesch, Samira; Mattos, Jacó Joaquim; Milani, Márcio Raimundo; Bainy, Afonso Celso Dias; Dafre, Alcir Luiz

    2014-01-01

    Zinc demonstrates protective and antioxidant properties at physiological levels, although these characteristics are not attributed at moderate or high concentrations. Zinc toxicity has been related to a number of factors, including interference with antioxidant defenses. In particular, the inhibition of glutathione reductase (GR) has been suggested as a possible mechanism for acute zinc toxicity in bivalves. The present work investigates the biochemical effects of a non-lethal zinc concentration on antioxidant-related parameters in gills of brown mussels Perna perna exposed for 21 days to 2.6 μM zinc chloride. After 2 days of exposure, zinc caused impairment of the antioxidant system, decreasing GR activity and glutathione levels. An increase in antioxidant defenses became evident at 7 and 21 days of exposure, as an increase in superoxide dismutase and glutathione peroxidase activity along with restoration of glutathione levels and GR activity. After 7 and 21 days, an increase in cellular peroxides and lipid peroxidation end products were also detected, which are indicative of oxidative damage. Changes in GR activity contrasts with protein immunoblotting data, suggesting that zinc produces a long lasting inhibition of GR. Contrary to the general trend in antioxidants, levels of peroxiredoxin 6 decreased after 21 days of exposure. The data presented here support the hypothesis that zinc can impair thiol homeostasis, causes an increase in lipid peroxidation and inhibits GR, imposing a pro-oxidant status, which seems to trigger homeostatic mechanisms leading to a subsequent increase on antioxidant-related defenses.

  13. Toxicity of copper, lead, and zinc mixtures to Ceriodaphnia dubia and Daphnia carinata.

    PubMed

    Cooper, Naomi L; Bidwell, Joseph R; Kumar, Anu

    2009-07-01

    Acute and chronic bioassays were conducted to determine the effects of copper, lead, and zinc mixtures on Ceriodaphnia dubia and Daphnia carinata. Copper, lead, and zinc combined at up to 5.2, 4.5, and 51.8 microg/L, respectively, did not cause significant mortality during acute exposures, although mixtures of 10.6, 9, and 101.1 microg/L and higher resulted in 65-100% mortality. Binary combinations of Cu+Zn (1.3+13.0 microg/L) and Cu+Pb (1.3+1.1 microg/L) and ternary combinations of Cu+Pb+Zn (1.3+1.1+13.0 microg/L) had a significant effect on reproduction of C. dubia. Toxic units and associated confidence intervals were calculated to characterize the nature of metal interactions. In most cases, and based on confidence intervals encompassing a value of 1, most of the metal interactions would be classified as additive. However, a more than additive effect was indicated by the acute tests for both species exposed to Cu+Pb, for D. carinata exposed to Cu+Zn, and for C. dubia exposed to all three metals.

  14. Baseline toxicity data for freshwater bryozoa exposed to copper, cadmium, chromium, and zinc

    SciTech Connect

    Pardue, W.J.; Wood, T.S.

    1980-01-01

    Four heavy metals - copper, cadmium, chromium, and zinc - were used to determine baseline toxicity data for three species of phylactolaemate bryozoa. Techniques used in germinating test organisms are described, and baseline toxicity data are presented. Minimal interspecific variation in toxicity was noted for each heavy metal. In general, copper was most toxic, followed by cadmium, chromium, and zinc. Available data indicate that bryozoans are more sensitive to these metals than many other invertebrates and fish.

  15. Measuring the acute toxicity of estuarine sediments

    SciTech Connect

    DeWitt, T.H.; Swartz, R.C.; Lanberson, J.O.

    1989-01-01

    Estuarine sediments frequently are repositories and sources of anthropogenic contaminants. Toxicity is one method of assessing the environmental quality of sediments, yet because of the extreme range of salinities that characterize estuaries few infaunal organisms have both the physiological tolerance and sensitivity to chemical contaminants to serve in estuarine sediment toxicity tests. The study describes research on the estuarine burrowing amphipod, Eohaustorius estuarius Bosworth, 1973, whose survival was >95% in control sediments across a 2 to 28% salinity range over 10-d periods. E. estuarius also was acutely sensitive to low sediment concentrations of the polycyclic aromatic hydrocarbon, fluoranthene (LC50 approximately = 10.6 mg/kg), and its sensitivity to fluoranthene was not affected by salinity. E. estuarius was almost as sensitive as Rhepoxynius abronius to fluoranthene and to field-collected sediments from Puget Sound urban and industrial bays. E. estuarius was also more tolerant of very fine, uncontaminated sediments than R. abronius. Furthermore, E. estuarius was more sensitive to sediments spiked with fluoranthene than the freshwater amphipod, Hyalella azteca. E. estuarius, and possibly other estuarine haustoriid species, appears to be an excellent candidate for testing the acute toxicity if estuarine and marine sediments.

  16. Complex role of zinc in methamphetamine toxicity in vitro.

    PubMed

    Aizenman, E; McCord, M C; Saadi, R A; Hartnett, K A; He, K

    2010-11-24

    Methamphetamine is a drug of abuse that can induce oxidative stress and neurotoxicity to dopaminergic neurons. We have previously reported that oxidative stress promotes the liberation of intracellular Zn(2+) from metal-binding proteins, which, in turn, can initiate neuronal injurious signaling processes. Here, we report that methamphetamine mobilizes Zn(2+) in catecholaminergic rat pheochromocytoma (PC12) cells, as measured by an increase in Zn(2+)-regulated gene expression driven by the metal response element transcription factor-1. Moreover, methamphetamine-liberated Zn(2+) was responsible for a pronounced enhancement in voltage-dependent K(+) currents in these cells, a process that normally accompanies Zn(2+)-dependent cell injury. Overnight exposure to methamphetamine induced PC12 cell death. This toxicity could be prevented by the cell-permeant zinc chelator N,N,N', N'-tetrakis(2-pyridylmethyl)-ethylenediamine (TPEN), and by over-expression of the Zn(2+)-binding protein metallothionein 3 (MT3), but not by tricine, an extracellular Zn(2+) chelator. The toxicity of methamphetamine to PC12 cells was enhanced by the presence of co-cultured microglia. Remarkably, under these conditions, TPEN no longer protected but, in fact, dramatically exacerbated methamphetamine toxicity, tricine again being without effect. Over-expression of MT3 in PC12 cells did not mimic these toxicity-enhancing actions of TPEN, suggesting that the chelator affected microglial function. Interestingly, P2X receptor antagonists reversed the toxicity-enhancing effect of TPEN. As such, endogenous levels of intracellular Zn(2+) may normally interfere with the activation of P2X channels in microglia. We conclude that Zn(2+) plays a significant but complex role in modulating the cellular response of PC12 cells to methamphetamine exposure in both the absence and presence of microglia.

  17. Presence of acute phase changes in zinc, iron, and copper metabolism in turkey embryos

    SciTech Connect

    Klasing, K.C.; Richards, M.P.; Darcey, S.E.; Laurin, D.E.

    1987-01-01

    Acute phase changes in trace mineral metabolism were examined in turkey embryos. An endotoxin injection resulted in increased concentrations of serum copper and liver zinc and decreased concentrations of serum zinc in embryos incubated either in ovo or ex ovo. Changes in zinc and copper metabolism occurred when endotoxin either was injected intramuscularly, into the amnionic fluid, or administered onto the chorioallantoic membrane. Unlike poults, embryos did not respond to an inflammatory challenge with decreased serum iron concentrations. Acute phase changes in embryo serum zinc and copper as well as liver zinc concentrations were similar to those in poults. Increased liver zinc concentrations were associated with increased zinc in metallothionein (MT). An injection of a crude interleukin 1 preparation into embryos resulted in similar increases in hepatic zinc and MT concentrations as an endotoxin injection, suggesting a role for this cytokine in mediating the acute phase changes in embryonic zinc metabolism.

  18. Extensive review of fish embryo acute toxicities for the prediction of GHS acute systemic toxicity categories.

    PubMed

    Scholz, Stefan; Ortmann, Julia; Klüver, Nils; Léonard, Marc

    2014-08-01

    Distribution and marketing of chemicals require appropriate labelling of health, physical and environmental hazards according to the United Nations global harmonisation system (GHS). Labelling for (human) acute toxicity categories is based on experimental findings usually obtained by oral, dermal or inhalative exposure of rodents. There is a strong societal demand for replacing animal experiments conducted for safety assessment of chemicals. Fish embryos are considered as alternative to animal testing and are proposed as predictive model both for environmental and human health effects. Therefore, we tested whether LC50s of the fish embryo acute toxicity test would allow effectively predicting of acute mammalian toxicity categories. A database of published fish embryo LC50 containing 641 compounds was established. For these compounds corresponding rat oral LD50 were identified resulting in 364 compounds for which both fish embryo LC50 and rat LD50 was available. Only a weak correlation of fish embryo LC50 and rat oral LD50 was obtained. Fish embryos were also not able to effectively predict GHS oral acute toxicity categories. We concluded that due to fundamental exposure protocol differences (single oral dose versus water-borne exposure) a reverse dosimetry approach is needed to explore the predictive capacity of fish embryos.

  19. Acute Oral Toxicity Up-And-Down-Procedure

    EPA Pesticide Factsheets

    The Up-and-Down Procedure is an alternative acute toxicity test that provides a way to determine the toxicity of chemicals with fewer test animals by using sequential dosing steps. Find out about this test procedure.

  20. Subacute toxic effects of zinc on various tissues and organs of rats.

    PubMed

    Piao, Fengyuan; Yokoyama, Kazuhito; Ma, Ning; Yamauchi, Toru

    2003-11-01

    In order to expand our knowledge of zinc toxicity and to assess further the toxicities of zinc systematically, we observed the toxic effects of zinc on the functions of various tissues and organs in rats. The rats were randomly divided into four groups (14 in each group), viz. one normal control group (received saline), two zinc groups (Znlow: 4 mg/kg of zinc acetate; Znhigh: 8 mg/kg of zinc acetate), and one cyclophosphamide group (50 mg/kg, as positive control of micronucleated polychromatic erythrocytes (MPCEs)). Saline and zinc acetate were administered intraperitoneally to the rats once every 2 days, seven times in total. Cyclophosphamide was given intraperitoneally to the rats once. The concentration of blood zinc was determined and accumulation of zinc was not observed in the experimental groups. The frequencies of basophilic stippled erythrocyte (BSE) and MPCEs in the Znhigh group were significantly higher than those in the control group (P<0.05). The levels of serum glutamic oxalacetic transaminase (GOT) and serum triiodothyronine (T3) in the Znhigh groups decreased significantly, compared with the control group (P<0.01 or 0.05). Moreover, we also observed that the level of serum cortisol, another adrenal corticoid hormone in rats, was increased by zinc acetate in a dose-dependent manner. According to the literature and our findings, exposure to zinc, especially at higher doses, may produce toxic effects on various tissues and organs including the hematopoietic system, cytogenetics, biochemistry and endocrine system function. Therefore, it is suggested that zinc should be used carefully, especially by high risk groups such as children and pregnant women despite its use as a food additive or in self-medication. At the same time, it is necessary to investigate and research further these toxicities of zinc with long-term administration of low dosage.

  1. Electrophiles and acute toxicity to fish.

    PubMed Central

    Hermens, J L

    1990-01-01

    Effect concentrations in fish LC50 tests with directly acting electrophiles are lower than those of unreactive chemicals that act by narcosis. LC50 values of more hydrophobic reactive chemicals tend to approach those of unreactive chemicals. Quantitative studies to correlate fish LC50 data to physical-chemical properties indicate that LC50 values of reactive chemicals depend on hydrophobicity as well as chemical reactivity. In this paper, several examples will be given of chemical structures that are known as direct electrophiles. This classification might be useful to identify chemicals that are more effective at lower concentrations than unreactive compounds. Chemicals that require bioactivation are not included because almost no information is available on the influence of bioactivation on acute toxic effects in aquatic organisms. PMID:2269228

  2. Acute toxicity of methanol to mytilus edulis

    SciTech Connect

    Helmstetter, A.; Gamerdinger, A.P.; Pruell, R.J.

    1996-12-31

    Methanol is being promoted as an alternative fuel because of the clean air benefits of reduced carbon monoxide and other by-product emissions. In the event of an accidental spill or leakage from a storage tank, there is limited data available on the impact of alternative fuels on marine ecosystems. Before considering the impact of methanol on ecosystem processes, it is necessary to establish the acute toxicity. The blue mussel (Mytilus edulis) was selected for study because of its use as an indicator species of marine ecosystem health (Widdows and Donkin 1992). Our primary objective was to determine the LC-50 value of methanol to adult Mytilus edulis. We also not sublethal effects that were observed during the course of the 96-hr exposure. 16 refs., 1 fig. 3 tabs.

  3. Paradoxical zinc toxicity and oxidative stress in the mammary gland during marginal dietary zinc deficiency

    PubMed Central

    Bostanci, Zeynep; Mack, Ronald P.; Lee, Sooyeon; Soybel, David I.; Kelleher, Shannon L.

    2014-01-01

    Zinc (Zn) regulates numerous cellular functions. Zn deficiency is common in females; ~80% of women and 40% of adolescent girls consume inadequate Zn. Zn deficiency enhances oxidative stress, inflammation and DNA damage. Oxidative stress and inflammation is associated with breast disease. We hypothesized that Zn deficiency increases oxidative stress in the mammary gland, altering the microenvironment and architecture. Zn accumulated in the mammary glands of Zn deficient mice and this was associated with macrophage infiltration, enhanced oxidative stress and over-expression of estrogen receptor α. Ductal and stromal hypercellularity was associated with aberrant collagen deposition and disorganized e-cadherin. Importantly, these microenvironmental alterations were associated with substantial impairments in ductal expansion and mammary gland development. This is the first study to show that marginal Zn deficiency creates a toxic microenvironment in the mammary gland impairing breast development. These changes are consistent with hallmarks of potential increased risk for breast disease and cancer. PMID:25088245

  4. Prenatal development toxicity study of zinc oxide nanoparticles in rats

    PubMed Central

    Hong, Jeong-Sup; Park, Myeong-Kyu; Kim, Min-Seok; Lim, Jeong-Hyeon; Park, Gil-Jong; Maeng, Eun-Ho; Shin, Jae-Ho; Kim, Meyoung-Kon; Jeong, Jayoung; Park, Jin-A; Kim, Jong-Choon; Shin, Ho-Chul

    2014-01-01

    This study investigated the potential adverse effects of zinc oxide nanoparticles ([ZnOSM20(+) NPs] zinc oxide nanoparticles, positively charged, 20 nm) on pregnant dams and embryo–fetal development after maternal exposure over the period of gestational days 5–19 with Sprague-Dawley rats. ZnOSM20(+) NPs were administered to pregnant rats by gavage at 0, 100, 200, and 400 mg/kg/day. All dams were subjected to a cesarean section on gestational day 20, and all of the fetuses were examined for external, visceral, and skeletal alterations. Toxicity in the dams manifested as significantly decreased body weight after administration of 400 mg/kg/day NPs; reduced food consumption after administration of 200 and 400 mg/kg/day NPs; and decreased liver weight and increased adrenal glands weight after administration of 400 mg/kg/day NPs. However, no treatment-related difference in: number of corpora lutea; number of implantation sites; implantation rate (%); resorption; dead fetuses; litter size; fetal deaths and placental weights; and sex ratio were observed between the groups. On the other hand, significant decreases between treatment groups and controls were seen for fetal weights after administration of 400 mg/kg/day NPs. Morphological examinations of the fetuses demonstrated significant differences in incidences of abnormalities in the group administered 400mg/kg/day. Meanwhile, no significant difference was found in the Zn content of fetal tissue between the control and high-dose groups. These results showed that oral doses for the study with 15-days repeated of ZnOSM20(+) NPs were maternotoxic in the 200 mg/kg/day group, and embryotoxic in the 400 mg/kg/day group. PMID:25565834

  5. Exposure of cultured human proximal tubular cells to cadmium, mercury, zinc and bismuth: toxicity and metallothionein induction.

    PubMed

    Rodilla, V; Miles, A T; Jenner, W; Hawksworth, G M

    1998-08-14

    The kidney, in particular the proximal convoluted tubule, is a major target site for the toxic effects of various metals. However, little is known about the early effects of these metals after acute exposure in man. In the present study we have evaluated the toxicity of several inorganic metal compounds (CdCl2, HgCl2, ZnCl2, and Bi(NO3)3) and the induction of metallothionein by these compounds in cultured human proximal tubular (HPT) cells for up to 4 days. The results showed that bismuth was not toxic even at the highest dose (100 microM) used, while zinc, cadmium and mercury exhibited varying degrees of toxicity, zinc being the least toxic and mercury the most potent. A significant degree of interindividual variation between the different isolates used in these experiments was also observed. All metals used in the present study induced MT, as revealed by immunocytochemistry. All metals showed maximal induction between 1 and 3 days after treatment. Although a certain amount of constitutive MT was present in the cultures, the intensity of the staining varied with time in culture and between the different isolates studied. No correlation could be made between the intensity of the staining in control cultures (indicating total amount of constitutive MT) and the susceptibility of a given isolate to metal toxicity. Furthermore, no correlation could be made between metal-induced MT and the susceptibility of a given isolate to that particular metal.

  6. Acute and environmental toxicity studies with hexazinone

    SciTech Connect

    Kennedy, G.L. Jr.

    1984-08-01

    The acute toxicity of hexazinone, a herbicide intended for general noncropland areas and selected crop uses (alfalfa and sugarcane), has been evaluated to establish proper handling guidelines and to measure its potential impact on the environment. The material is slightly to moderately toxic when given as a single oral dose; its LD50 in male rats is 1690 mg/kg, in male guinea pigs 860 mg/kg, and in male dogs greater than 3400 mg/kg although in the dog emesis prevented accurate quantitation. When the material is administered intraperitoneally, the LD50 in rats is 530 mg/kg. In both studies, no gross or histologic alterations were apparent. Hexazinone is a moderate to severe eye irritant in the rabbit and produced only mild erythema in rabbit skin at 5278 mg/kg, a dose which did not produce lethality or other clinical signs. Subchronic dermal exposures (10 consecutive doses) to rabbits produced increases in serum alkaline phosphatase and glutamic-pyruvic transaminase at the highest levels tested (680 and 770 mg/kg in two separate experiments) with no effects seen at 150 mg/kg. One-hour inhalation exposure of up to 7.48 mg/liter did not produce mortality in rats.

  7. Acute toxicity and chemistry of urban and nonurban bed material, Maricopa County, Arizona

    SciTech Connect

    Lopes, T.J.

    1995-12-31

    The acute toxicity and chemistry of bed material in the Phoenix, Arizona, area were characterized to determine if urban activities degrade bed-material quality. Samples were collected from unpaved lots and ephemeral channels in urban and undeveloped drainage basins. Samples were sieved to less than 63 microns to make comparisons between samples and were analyzed for constituent concentrations and acute toxicity using the amphipod Hyalella azteca. Analysis of variance with Tukeys` multiple comparison test indicated that bed-material samples from the undeveloped drainage basin were more toxic than samples from ephemeral channels. The toxicity of bed material was not significantly different between undeveloped and urban drainage basins and between urban drainage basins and ephemeral channels. The most toxic bed-material samples from urban drainage basins appeared to be those samples collected from areas where stormwater accumulates. Concentrations of ammonia, lead, cadmium, and zinc were significantly greater in urban bed-material samples than in samples from the undeveloped drainage basin and ephemeral channels. Zinc and cadmium were associated with organic carbon in urban bed-material samples, and trace metals were associated with iron and manganese in samples from the undeveloped drainage basin. Mortality rates in bed-material samples from the undeveloped drainage basin moderately correlated with recoverable concentrations of zinc (rank correlation of 0.71), lead (0.59), and copper (0.46). Mortality rates in bed-material samples from urban drainage basins significantly correlated with recoverable concentrations of cadmium (0.81) and zinc (0.70).The association of trace metals with iron and manganese seemed to increase trace-metal bioavailability when compared with trace metals associated with organic carbon.

  8. Implementing Lecane quadridentata acute toxicity tests to assess the toxic effects of selected metals (Al, Fe and Zn).

    PubMed

    Guzmán, Félix Torres; González, Francisco Javier Avelar; Martínez, Roberto Rico

    2010-03-01

    An environmental study revealed that three metals (Al, Fe and Zn) are common in the San Pedro River (SPR) (Aguascalientes, Mexico). Regrettably, in many samples the concentrations of these metals exceeded the maximum allowed toxicant concentrations levels as defined in by Mexican legislation. The highest concentrations of the three metals were found during the 2005 dry season, with elevated Al concentrations present along the entire river. Not surprisingly, the highest concentrations for all three metals came from locations adjacent to industrial areas. Estimates of the contribution of these metals to total toxicity revealed that these three metals are important contaminants of the river and responsible for most of the lethal toxicity found in environmental samples. To assess the importance of these reports, we conducted acute toxicity tests to determine LC50 for Al, Fe and Zn on the freshwater rotifer Lecane quadridentata. This permitted us to estimate the contribution of these metals to total toxicity during 2005-2006. Based on LC50 values, all three metals should be considered very toxic, with the zinc LC50 value (0.12 mg L(-1)) making it the most toxic metal for L. quadridentata. This approach can be applied to other sites with similar concentrations of these metals.

  9. The effects of chronological age and size on toxicity of zinc to juvenile brown trout

    EPA Science Inventory

    A series of toxicity tests were conducted to investigate the role of chronological age and organism weight on zinc tolerance in juvenile brown trout (Salmo trutta). Four different incubation temperatures were used to control the maturation of the juveniles prior to zinc exposure...

  10. Acute and environmental toxicity studies with hexazinone.

    PubMed

    Kennedy, G L

    1984-08-01

    The acute toxicity of hexazinone, a herbicide intended for general noncropland areas and selected crop uses (alfalfa and sugarcane), has been evaluated to establish proper handling guidelines and to measure its potential impact on the environment. The material is slightly to moderately toxic when given as a single oral dose; its LD50 in male rats is 1690 mg/kg, in male guinea pigs 860 mg/kg, and in male dogs greater than 3400 mg/kg although in the dog emesis prevented accurate quantitation. When the material is administered intraperitoneally, the LD50 in rats is 530 mg/kg. Repeated doses (five oral doses per week for 2 weeks) of 300 mg/kg to rats produced slight weight loss in one of two replicate experiments. In both studies, no gross or histologic alterations were apparent. Hexazinone is a moderate to severe eye irritant in the rabbit and produced only mild erythema in rabbit skin at 5278 mg/kg, a dose which did not produce lethality or other clinical signs. Subchronic dermal exposures (10 consecutive doses) to rabbits produced increases in serum alkaline phosphatase and glutamic-pyruvic transaminase at the highest levels tested (680 and 770 mg/kg in two separate experiments) with no effects seen at 150 mg/kg. There were no alterations in livers from treated rabbits examined by light microscopy. No dermal sensitization was produced when concentrations of up to 50% were tested in guinea pigs. One-hour inhalation exposure of up to 7.48 mg/liter did not produce mortality in rats.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. A microfluidic device for continuous sensing of systemic acute toxicants in drinking water.

    PubMed

    Zhao, Xinyan; Dong, Tao

    2013-12-03

    A bioluminescent-cell-based microfluidic device for sensing toxicants in drinking water was designed and fabricated. The system employed Vibrio fischeri cells as broad-spectrum sensors to monitor potential systemic cell toxicants in water, such as heavy metal ions and phenol. Specifically, the chip was designed for continuous detection. The chip design included two counter-flow micromixers, a T-junction droplet generator and six spiral microchannels. The cell suspension and water sample were introduced into the micromixers and dispersed into droplets in the air flow. This guaranteed sufficient oxygen supply for the cell sensors. Copper (Cu2+), zinc (Zn2+), potassium dichromate and 3,5-dichlorophenol were selected as typical toxicants to validate the sensing system. Preliminary tests verified that the system was an effective screening tool for acute toxicants although it could not recognize or quantify specific toxicants. A distinct non-linear relationship was observed between the zinc ion concentration and the Relative Luminescence Units (RLU) obtained during testing. Thus, the concentration of simple toxic chemicals in water can be roughly estimated by this system. The proposed device shows great promise for an early warning system for water safety.

  12. [Effect of zinc on reproductive toxicity in rats].

    PubMed

    Wei, Qing; Fan, Ruiquan; Yang, Xingfen; Chen, Tiejiang

    2003-11-01

    The purpose of this study was to explore the effect of zinc on reproductive function in rats. The results revealed that the sperm count, sperm motility and reproductive function appeared to be enhanced in male rats by 60 days successive administration of low dose zinc (12 mg/kg) or medium dose zinc (120 mg/kg), whereas reproductive system damages characterized by lowering of reproductive function would be resulted by high dose zinc(240 mg/kg). However, no effect on the growth and development of the second generation was shown, suggesting that the injury was just limited to certain extent.

  13. Zinc Modulates Nanosilver-Induced Toxicity in Primary Neuronal Cultures.

    PubMed

    Ziemińska, Elżbieta; Strużyńska, Lidia

    2016-02-01

    Silver nanoparticles (NAg) have recently become one of the most commonly used nanomaterials. Since the ability of nanosilver to enter the brain has been confirmed, there has been a need to investigate mechanisms of its neurotoxicity. We previously showed that primary neuronal cultures treated with nanosilver undergo destabilization of calcium homeostasis via a mechanism involving glutamatergic NMDA receptors. Considering the fact that zinc interacts with these receptors, the aim of the present study was to examine the role of zinc in mechanisms of neuronal cell death in primary cultures. In cells treated with nanosilver, we noted an imbalance between extracellular and intracellular zinc levels. Thus, the influence of zinc deficiency and supplementation on nanosilver-evoked cytotoxicity was investigated by treatment with TPEN (a chelator of zinc ions), or ZnCl(2), respectively. Elimination of zinc leads to complete death of nanosilver-treated CGCs. In contrast, supplementation with ZnCl(2) increases viability of CGCs in a dose-dependent manner. Addition of zinc provided protection against the extra/intracellular calcium imbalance in a manner similar to MK-801, an antagonist of NMDA receptors. Zinc chelation by TPEN decreases the mitochondrial potential and dramatically increases the rate of production of reactive oxygen species. Our results indicate that zinc supplementation positively influences nanosilver-evoked changes in CGCs. This is presumed to be due to an inhibitory effect on NMDA-sensitive calcium channels.

  14. [Acute toxicity of different type pesticide surfactants to Daphnia magna].

    PubMed

    Li, Xiu-huan; Li, Hua; Chen, Cheng-yu; Li, Jian-tao; Liu, Feng

    2013-08-01

    By using the standard test methods in Experimental Guideline for Environmental Safety Evaluation of Chemical Pesticide to aquatic organisms, a comparative study was conducted on the acute toxicity of 39 nonionic, 6 anionic, and 3 cationic surfactants to Daphnia magna. The acute toxicity of three cationic surfactants 1427, 1227 and C8-10 to D. magna belonged to virulent level, and the toxicity of 1427 was the highest, with the EC50 value being 0.97 x 10(-2) mg x L(-1). The acute toxicity of nonionic surfactants polyoxyethylene ether castor oil EL, Tween, and Span emulsifiers belonged to low level, but the toxicity of alkylphenol polyoxyethylene ether and fatty alcohol polyoxyethylene ether surfactants was relatively high, of which, AEO-7 and AEO-5 displayed high toxicity, with the EC50 value being 0.82 and 0.97 mg x L(-1), respectively. In these surfactants, the more liposolubility, the higher the toxicity was. Most of the anionic surfactants were medium in toxicity, but the acute toxicity of NNO belonged to high toxicity, with the EC50 value being 0.17 mg x L(-1).

  15. Acute changes in cellular zinc alters zinc uptake rates prior to zinc transporter gene expression in Jurkat cells.

    PubMed

    Holland, Tai C; Killilea, David W; Shenvi, Swapna V; King, Janet C

    2015-12-01

    A coordinated network of zinc transporters and binding proteins tightly regulate cellular zinc levels. Canonical responses to zinc availability are thought to be mediated by changes in gene expression of key zinc transporters. We investigated the temporal relationships of actual zinc uptake with patterns of gene expression in membrane-bound zinc transporters in the human immortalized T lymphocyte Jurkat cell line. Cellular zinc levels were elevated or reduced with exogenous zinc sulfate or N,N,N',N-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), respectively. Excess zinc resulted in a rapid 44 % decrease in the rate of zinc uptake within 10 min. After 120 min, the expression of metallothionein (positive control) increased, as well as the zinc exporter, ZnT1; however, the expression of zinc importers did not change during this time period. Zinc chelation with TPEN resulted in a rapid twofold increase in the rate of zinc uptake within 10 min. After 120 min, the expression of ZnT1 decreased, while again the expression of zinc importers did not change. Overall, zinc transporter gene expression kinetics did not match actual changes in cellular zinc uptake with exogenous zinc or TPEN treatments. This suggests zinc transporter regulation may be the initial response to changes in zinc within Jurkat cells.

  16. Acute aquatic toxicity and biodegradation potential of biodiesel fuels

    SciTech Connect

    Haws, R.A.; Zhang, X.; Marshall, E.A.; Reese, D.L.; Peterson, C.L.; Moeller, G.

    1995-12-31

    Recent studies on the biodegradation potential and aquatic toxicity of biodiesel fuels are reviewed. Biodegradation data were obtained using the shaker flask method observing the appearance of CO{sub 2} and by observing the disappearance of test substance with gas chromatography. Additional BOD{sub 5} and COD data were obtained. The results indicate the ready biodegradability of biodiesel fuels as well as the enhanced co-metabolic biodegradation of biodiesel and petroleum diesel fuel mixtures. The study examined reference diesel, neat soy oil, neat rape oil, and the methyl and ethyl esters of these vegetable oils as well as various fuel blends. Acute toxicity tests on biodiesel fuels and blends were performed using Oncorhynchus mykiss (Rainbow Trout) in a static non-renewal system and in a proportional dilution flow replacement system. The study is intended to develop data on the acute aquatic toxicity of biodiesel fuels and blends under US EPA Good Laboratory Practice Standards. The test procedure is designed from the guidelines outlined in Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms and the Fish Acute Aquatic Toxicity Test guideline used to develop aquatic toxicity data for substances subject to environmental effects test regulations under TSCA. The acute aquatic toxicity is estimated by an LC50, a lethal concentration effecting mortality in 50% of the test population.

  17. Temperature, physiological time, and zinc toxicity in the isopod, Porcellio scaber

    SciTech Connect

    Donker, M.H.; Van Straalen, N.M.; Abdel-Lateif, H.M.; Khalil, M.A.; Bayoumi, B.M.

    1998-08-01

    Temperature is an important controlling factor in the metabolism of ectotherms, and it may interact with the toxicity of heavy metals in a variety of ways. In this work, a study on the effect of different zinc concentrations on growth of the isopod, Porcellio scaber was conducted using four temperature levels. The results demonstrated a significant effect for both zinc and temperature on the growth rate; the interaction between zinc and temperature was also significant. The Arrhenius function was used to describe the temperature-growth rate relationship, from which estimates for the activation energy were derived. A tendency for activation energy to decrease with increasing zinc concentration was observed. Isopods exposed to 13 {micro}mol Zn/g had the highest activation energy and the highest growth rate. To analyze the effect of temperature on the internal body concentration of zinc, the exposure time was transformed into physiological time, calibrated at 15 C, for all experimental groups using the activation energies estimated earlier. The rate of zinc accumulation was derived from the relationship between internal body concentration and physiological exposure time. Differences between isopods cultured at different temperatures could be explained well by the effect of physiological exposure time. The interaction between temperature and zinc toxicity seems to be due not to increased accumulation of zinc at higher temperatures as such but to a physiological interaction with the energy metabolism.

  18. Metal toxicity, uptake and bioaccumulation in aquatic invertebrates--modelling zinc in crustaceans.

    PubMed

    Rainbow, P S; Luoma, S N

    2011-10-01

    We use published data on the different patterns of the bioaccumulation of zinc by three crustaceans, the caridean decapod Palaemon elegans, the amphipod Orchestia gammarellus and the barnacle Amphibalanus amphitrite, to construct comparative biodynamic models of the bioaccumulation of zinc into metabolically available and detoxified components of accumulated zinc in each crustacean under both field and laboratory toxicity test conditions. We then link these bioaccumulation models to the onset of toxic effects on exposure of the crustaceans to high dissolved zinc bioavailabilities, using the tenets that toxicity effects are related to the total uptake rate of the toxic metal, and that toxicity is not usually dependent on the total accumulated metal concentration but always on the concentration of accumulated metal that is metabolically available. We dismiss the general concept that there is a critical accumulated body concentration of a metal in an invertebrate at which toxicity ensues, except under specific circumstances involving a rare lack of storage detoxification of accumulated metal. We thus propose a theoretical framework that can be extended to other metals and other aquatic invertebrates (indeed other animals) to explain the variation in the relationship between bioaccumulated body concentrations and toxicity, and subsequently to predict this relationship in many other species for which we have bioaccumulation modelling data.

  19. Comparison of standard acute toxicity tests with rapid-screening toxicity tests

    SciTech Connect

    Toussaint, M.W.; Shedd, T.R.; VanDerSchal, W.H.; Leather, G.R.

    1995-10-01

    This study compared the relative sensitivity of five inexpensive, rapid toxicity tests to the sensitivity of five standard aquatic acute toxicity tests through literature review and testing. The rapid toxicity tests utilized organisms that require little culturing or handling prior to testing: a freshwater rotifer (Branchionus ccalyciflorus); brine shrimp (Artemia salina); lettuce (Lactuca sativa); and two microbial tests (Photo bacterium phosphoreum - Microtox test, and a mixture of bacterial species - the polytox test). Standard acute toxicity test species included water fleas (Daphnia magna and Ceriadaphnta dubia), green algae (Setenastrum capricarnutum), fathead minnows (Pimephalespromelas), and mysid shrimp (Mysidopsis bahia). Sensitivity comparisons between rapid and standard acute toxicity tests were based on LC5O/EC50 data from 11 test chemicals. Individually, the lettuce and rotifer tests ranked most similar in sensitivity to the standard tests, while Microtox fell just outside the range of sensitivities represented by the group of standard acute toxicity tests. The brine shrimp and Polytox tests were one or more orders of magnitude different from the standard acute toxicity tests for most compounds. The lettuce, rotifer, and Microtox tests could be used as a battery for preliminary toxicity screening of chemicals. Further evaluation of complex real-world environmental samples is recommended.

  20. A comparison of standard acute toxicity tests with rapid-screening toxicity tests

    SciTech Connect

    Toussaint, M.W.; Shedd, T.R.; Schalie, W.H. van der; Leather, G.R.

    1995-05-01

    This study compared the relative sensitivity of five inexpensive, rapid toxicity tests to the sensitivity of five standard aquatic acute toxicity tests through literature review and testing. The rapid toxicity tests utilized organisms that require little culturing or handling prior to testing: a freshwater rotifer (Branchionus calyciflorus); brine shrimp (Artemia salina); lettuce (Lactuca sativa); and two microbial tests (Photobacterium phosphoreum--Microtox{reg_sign} test, and a mixture of bacterial species--the Polytox{reg_sign} test). Standard acute toxicity test species included water fleas (Daphnia magna and Ceriodaphnia dubia), green algae (Selenastrum capricornutum), fathead minnows (Pimephales promelas), and mysid shrimp (Mysidopsis bahia). Sensitivity comparisons between rapid and standard acute toxicity tests were based on LC50/EC50 data from 11 test chemicals. Individually, the lettuce and rotifer tests ranked most similar in sensitivity to the standard tests, while Microtox fell just outside the range of sensitivities represented by the group of standard acute toxicity tests. The brine shrimp and Polytox tests were one or more orders of magnitude different from the standard acute toxicity tests for most compounds. The lettuce, rotifer, and Microtox tests could be used as a battery for preliminary toxicity screening of chemicals. Further evaluation of complex real-world environmental samples is recommended.

  1. Zinc inhibits the reproductive toxicity of Zearalenone in immortalized murine ovarian granular KK-1 cells.

    PubMed

    Li, Yijia; He, Xiaoyun; Yang, Xuan; Huang, Kunlun; Luo, Yunbo; Zhu, Liye; Li, Yuzhe; Xu, Wentao

    2015-09-23

    Zearalenone (ZEA) mainly injures the reproductive system of mammals. In the present study, we aimed to explore the mechanism by which zinc inhibits ZEA-induced reproductive damage in KK-1 cells for the first time. The results shown that both zinc sulfate and zinc gluconate addition increased the intracellular zinc concentration and influenced the expression of zinc transporters (Slc30a1 and Slc39a1) in a time-dependent manner. Co-incubation of zinc with ZEA significantly reduced the ZEA-induced reactive oxygen species and malondialdehyde elevation by promoting the transcription of Mtf1 and Mt2. Meanwhile, two different zincs inhibited the ZEA-induced loss of mitochondrial membrane potential and elevation of late-stage apoptosis via activating the mitochondrial apoptotic pathway by recovering the mRNA and protein expression of pro-apoptotic genes (Bax, Casp3, Casp9). Zinc also recovered cells from S-phase cell cycle arrest. In addition, both of them promoted the ZEA-induced estrogen production but regulated the expression of steroidogenic enzymes (Star, Cyp11a1, Hsd3b1, Cyp17a1) in different way. All these results indicated that zinc could inhibit the reproductive toxicity of ZEA.

  2. Zinc inhibits the reproductive toxicity of Zearalenone in immortalized murine ovarian granular KK-1 cells

    PubMed Central

    Li, Yijia; He, Xiaoyun; Yang, Xuan; Huang, Kunlun; Luo, Yunbo; Zhu, Liye; Li, Yuzhe; Xu, Wentao

    2015-01-01

    Zearalenone (ZEA) mainly injures the reproductive system of mammals. In the present study, we aimed to explore the mechanism by which zinc inhibits ZEA-induced reproductive damage in KK-1 cells for the first time. The results shown that both zinc sulfate and zinc gluconate addition increased the intracellular zinc concentration and influenced the expression of zinc transporters (Slc30a1 and Slc39a1) in a time-dependent manner. Co-incubation of zinc with ZEA significantly reduced the ZEA-induced reactive oxygen species and malondialdehyde elevation by promoting the transcription of Mtf1 and Mt2. Meanwhile, two different zincs inhibited the ZEA-induced loss of mitochondrial membrane potential and elevation of late-stage apoptosis via activating the mitochondrial apoptotic pathway by recovering the mRNA and protein expression of pro-apoptotic genes (Bax, Casp3, Casp9). Zinc also recovered cells from S-phase cell cycle arrest. In addition, both of them promoted the ZEA-induced estrogen production but regulated the expression of steroidogenic enzymes (Star, Cyp11a1, Hsd3b1, Cyp17a1) in different way. All these results indicated that zinc could inhibit the reproductive toxicity of ZEA. PMID:26395757

  3. Acute and chronic toxicity studies with monochlorobenzene in rainbow trout

    USGS Publications Warehouse

    Dahlich, G.M.; Larson, R.E.; Gingerich, W.H.

    1982-01-01

    The toxicity of monochlorobenzene (CB) was investigated in rainbow trout following acute intraperitoneal (i.p.) administration and chronic exposure via the water in a continuously flowing system for 15 or 30 days. In the acute study overt toxicity and hepatotoxicity were monitored over a 96-h time period. Variables measured to assess toxicity included weight changes, liver weight to body weight ratios, behavioral changes, alanine aminotransferase activity (GPT), sulfobromophthalein (BSP) retention, total plasma protein concentration and liver histopathology. In the chronic study the same measures of toxicity were followed as well as food consumption and alkaline phosphatase (AP) activity. Upon acute i.p. exposure the toxicant (9.8 mmol/kg) caused behavioral changes in the fish which were consistent with the known anesthetic properties of CB in mammals. Elevations in BSP retention and GPT activity, and histopathology indicated that CB was hepatotoxic in fish. The LC50 of CB in trout exposed via the water for 96 h was 4.7 mg/l. Chronic exposure of trout to 2 or 3 mg/l CB resulted in similar behavioral changes as seen in the acute study. Liver toxicity was evident from elevations in GPT activity. BSP retention and AP activity appeared to be affected by the nutritional status of the trout as much as by the CB treatment. After 30 days of exposure to 3 mg/l CB, trout appeared to have developed some tolerance to the toxic effects.

  4. Towards a scheme of toxic equivalency factors (TEFs) for the acute toxicity of PAHs in sediment.

    PubMed

    Fisher, Tom T; Law, Robin J; Rumney, Heather S; Kirby, Mark F; Kelly, Carole

    2011-11-01

    Toxic equivalency factors/quotients (TEF/TEQs) express the toxicity of complex mixtures. For PAHs, TEF values are available for assessing their carcinogenic potential and are expressed as benzo[a]pyrene equivalents. This study develops a similar approach for their acute toxicity in sediments. Acute toxicity (10 day EC₅₀) values were generated using the marine amphipod Corophium volutator bioassay for twelve low molecular weight PAHs. The results ranged from 24 to > 1000 mg/Kg sediment dry weight for 4-methyldibenzothiophene and anthracene, respectively. Phenanthrene was used as the reference compound (TEF=1) and so the TEQ values derived are expressed as phenanthrene equivalents. In order to illustrate the applicability of this approach to the development of marine indicators we plotted TEQ values for acute toxicity to UK environmental monitoring data. Further work is required to validate the TEF values produced and to extend the TEQ approach to include a wider range of low molecular weight PAHs.

  5. Identification of acute toxicants in New Bedford Harbor sediments

    SciTech Connect

    Ho, K.T.; McKinney, R.A.; Kuhn, A.; Pelletier, M.C.; Burgess, R.M.

    1997-03-01

    New Bedford Harbor (NBH) is a marine Superfund site contaminated with high concentrations of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and metals. Experiments were conducted to determine the causal toxic agent(s) in pore waters from New Bedford Harbor sediments to amphipods and mysid shrimp. Chemical manipulations to characterize toxicity revealed that pore-water toxicity was organic in nature. Fractionation and subsequent mass spectral identification of peaks in the toxic fraction indicated that PCBs. PAHs, and unknown compounds were present. Comparisons of PAH LC50s and PAH concentrations in this fraction indicated that the toxicity was not due to PAHs because the PAH concentrations were much lower than the reported PAH LC50s. One unknown peak was positively identified as bis(2-ethylhexyl) phthalate, and the other tentatively identified as pyrazole. Toxicity tests and comparison of toxicity in the blank and toxic fractions eliminated the two unknowns as toxic causal agents. The authors determined the range of PCB LC50s to fall between 10 and 110 ppb for Mysidopsis bahia and Ampelisca abdita. Concentrations of PCBs for the toxic fractions ranged from 12 to 27 ppb. This range falls within the observed PCB LC50s for M. bahia and A. abdita. Based upon these PCB concentrations, they concluded that PCBs were the acute toxic agents in NBH pore waters. Other compounds in the toxic fractions, or compounds that coeluted and were undistinguished from PCBs had minor contributions to the measured toxicity.

  6. Acute toxicity of the herbicide bromoxynil to Daphnia magna

    USGS Publications Warehouse

    Buhl, Kevin J.; Hamilton, Steven J.; Schmulbach, James C.

    1993-01-01

    The acute toxicities of technical-grade bromoxynil octanoate (BO) and two commercial formulations, Buctril® and Bronate®, to < 24-h-old neonate Daphnia magna (Straus) were determined in soft, hard, and oligosaline water. In addition, effects of life stage, feeding, aging the herbicide, and exposure duration on BO toxicity to daphnids were investigated. Regardless of formulation, life stage, and water quality, BO was found to be extremely to highly toxic to daphnids in standard tests; 48-h EC50 values ranged from 41 to 161 m̈g/L. Bromoxynil octanoate was the most toxic to neonates in soft water and the least toxic in hard water. The acute toxicities of the three bromoxynil herbicides to a given age group of daphnids were similar within the same water type. Overall, neonates and 7-d-old adults were more sensitive than 14- or 15-d-old adults to each herbicide. Feeding daphnids during the toxicity test significantly decreased BO toxicity compared to not feeding them. Aging BO (as Buctril) in hard water decreased its toxicity, and the rate of deactivation was rapid, with an estimated half-life of biological activity of 13 h. Daphnids immobilized by exposures to toxic BO concentrations for ≤ 6 h recovered their mobility, whereas exposures of 18 and 24 h to BO produced toxic effects in daphnids similar to those exposed for 48 h. These results indicated that standard continuous exposure tests may not adequately predict the acute toxicity of BO to freshwater animals in the field.

  7. Evaluation of nano-specific toxicity of zinc oxide, copper oxide, and silver nanoparticles through toxic ratio

    NASA Astrophysics Data System (ADS)

    Zhang, Weicheng; Liu, Xiawei; Bao, Shaopan; Xiao, Bangding; Fang, Tao

    2016-12-01

    For safety and environmental risk assessments of nanomaterials (NMs) and to provide essential toxicity data, nano-specific toxicities, or excess toxicities, of ZnO, CuO, and Ag nanoparticles (NPs) (20, 20, and 30 nm, respectively) to Escherichia coli and Saccharomyces cerevisiae in short-term (6 h) and long-term (48 h) bioassays were quantified based on a toxic ratio. ZnO NPs exhibited no nano-specific toxicities, reflecting similar toxicities as ZnO bulk particles (BPs) (as well as zinc salt). However, CuO and Ag NPs yielded distinctly nano-specific toxicities when compared with their BPs. According to their nano-specific toxicities, the capability of these NPs in eliciting hazardous effects on humans and the environment was as follows: CuO > Ag > ZnO NPs. Moreover, long-term bioassays were more sensitive to nano-specific toxicity than short-term bioassays. Overall, nano-specific toxicity is a meaningful measurement to evaluate the environmental risk of NPs. The log T e particle value is a useful parameter for quantifying NP nano-specific toxicity and enabling comparisons of international toxicological data. Furthermore, this value could be used to determine the environmental risk of NPs.

  8. Acute toxicity of seeds of the sapodilla (Achras sapota L.).

    PubMed

    Singh, P D; Simon, W R; West, M E

    1984-01-01

    An aqueous extract of the sapodilla seed (Achras sapota L.) was acutely toxic to mice and rats (i.p. LD50 = 190 and 250 mg/kg, respectively) with symptoms of dyspnoea, apnoea and convulsions. Soxhlet extraction and chromatographic separation of the seed constituents yielded a brown amorphous solid containing saponin. This was heat-stable and toxic by the i.p. route (LD50 = 30-50 mg/kg) but non-toxic by the oral route in mice and rats. It is proposed that the toxicity of the sapodilla seed is due mainly to the saponin content.

  9. [Acute toxic hepatitis due to drinking water].

    PubMed

    Martínez Amate, Eva; Rodríguez Manrique, Marco A; González Sánchez, Mercedes; Casado Martin, Marta

    2010-11-01

    Toxic-induced liver disease is uncommon, although the true proportion of cases of hepatotoxicity is unknown, as this entity is underdiagnosed and underreported. The main reasons why toxic-induced liver disease goes unnoticed is the lack of pathognomonic data and the lack of spontaneous reporting by doctors and pharmacists. In some cases, the toxic substance can leave its «signature» in the form of clinical semiology suggestive of an underlying toxic cause. We present a case of hepatotoxicity induced by drinking water (chlorinated), which produced a reactive metabolites syndrome (trihalomethanes from the reaction of chlorine with organic products). Although the clinical presentation was typical, the case posed a diagnostic challenge for the various professionals involved.

  10. Acute toxicity prediction to threatened and endangered ...

    EPA Pesticide Factsheets

    Evaluating contaminant sensitivity of threatened and endangered (listed) species and protectiveness of chemical regulations often depends on toxicity data for commonly tested surrogate species. The U.S. EPA’s Internet application Web-ICE is a suite of Interspecies Correlation Estimation (ICE) models that can extrapolate species sensitivity to listed taxa using least-squares regressions of the sensitivity of a surrogate species and a predicted taxon (species, genus, or family). Web-ICE was expanded with new models that can predict toxicity to over 250 listed species. A case study was used to assess protectiveness of genus and family model estimates derived from either geometric mean or minimum taxa toxicity values for listed species. Models developed from the most sensitive value for each chemical were generally protective of the most sensitive species within predicted taxa, including listed species, and were more protective than geometric means models. ICE model estimates were compared to HC5 values derived from Species Sensitivity Distributions for the case study chemicals to assess protectiveness of the two approaches. ICE models provide robust toxicity predictions and can generate protective toxicity estimates for assessing contaminant risk to listed species. Reporting on the development and optimization of ICE models for listed species toxicity estimation

  11. Ethambutol-induced toxicity is mediated by zinc and lysosomal membrane permeabilization in cultured retinal cells

    SciTech Connect

    Chung, Hyewon; Yoon, Young Hee; Hwang, Jung Jin; Cho, Kyung Sook; Koh, Jae Young; Kim, June-Gone

    2009-03-01

    Ethambutol, an efficacious antituberculosis agent, can cause irreversible visual loss in a small but significant fraction of patients. However, the mechanism of ocular toxicity remains to be established. We previously reported that ethambutol caused severe vacuole formation in cultured retinal cells, and that the addition of zinc along with ethambutol aggravated vacuole formation whereas addition of the cell-permeable zinc chelator, N,N,N',N'-tetrakis (2-pyridylmethyl) ethylenediamine (TPEN), reduced vacuole formation. To investigate the origin of vacuoles and to obtain an understanding of drug toxicity, we used cultured primary retinal cells from newborn Sprague-Dawley rats and imaged ethambutol-treated cells stained with FluoZin-3, zinc-specific fluorescent dye, under a confocal microscope. Almost all ethambutol-induced vacuoles contained high levels of labile zinc. Double staining with LysoTracker or MitoTracker revealed that almost all zinc-containing vacuoles were lysosomes and not mitochondria. Intracellular zinc chelation with TPEN markedly blocked both vacuole formation and zinc accumulation in the vacuole. Immunocytochemistry with antibodies to lysosomal-associated membrane protein-2 (LAMP-2) and cathepsin D, an acid lysosomal hydrolase, disclosed lysosomal activation after exposure to ethambutol. Immunoblotting after 12 h exposure to ethambutol showed that cathepsin D was released into the cytosol. In addition, cathepsin inhibitors attenuated retinal cell toxicity induced by ethambutol. This is consistent with characteristics of lysosomal membrane permeabilization (LMP). TPEN also inhibited both lysosomal activation and LMP. Thus, accumulation of zinc in lysosomes, and eventual LMP, may be a key mechanism of ethambutol-induced retinal cell death.

  12. Metal uptake and acute toxicity in zebrafish: common mechanisms across multiple metals.

    PubMed

    Alsop, Derek; Wood, Chris M

    2011-10-01

    Zebrafish larvae (Danio rerio) were used to examine the mechanisms of action and acute toxicities of metals. Larvae had similar physiological responses and sensitivities to waterborne metals as adults. While cadmium and zinc have previously been shown to reduce Ca(2+) uptake, copper and nickel also decreased Ca(2+) uptake, suggesting that the epithelial transport of all these metals is through Ca(2+) pathways. However, exposure to cadmium, copper or nickel for up to 48 h had little or no effect on total whole body Ca(2+) levels, indicating that the reduction of Ca(2+) uptake is not the acute toxic mechanism of these metals. Instead, mortalities were effectively related to whole body Na(+), which decreased up to 39% after 48 h exposures to different metals around their respective 96 h LC50s. Decreases in whole body K(+) were also observed, although they were not as pronounced or frequent as Na(+) losses. None of the metals tested inhibited Na(+) uptake in zebrafish (Na(+) uptake was in fact increased with exposure) and the observed losses of Na(+), K(+), Ca(2+) and Mg(2+) were proportional to the ionic gradients between the plasma and water, indicating diffusive ion loss with metal exposure. This study has shown that there is a common pathway for metal uptake and a common mechanism of acute toxicity across groups of metals in zebrafish. The disruption of ion uptake accompanying metal exposure does not appear to be responsible for the acute toxicity of metals, as has been previously suggested, but rather the toxicity is instead due to total ion loss (predominantly Na(+)).

  13. On the performance of acute toxicity tests using the National Reference Toxicant Database

    SciTech Connect

    Zaidhk, B.

    1995-12-31

    The US National Reference Toxicant Database was used to compile data from 158 Ceriodaphnia dubia, and 187 fathead minnow acute toxicity tests. The data are analyzed using the EPA flow-chart for acute toxicity tests to determine the distribution of test methods selected. The data are reanalyzed using maximum likelihood estimation assuming probit, logit and Gompertz tolerance distributions and non-parametrically using the Spearman-Karber method with and without trimming. The results of these analyses are compared with respect to mean square error for the parametric methods and confidence intervals for the point estimate for all analyses.

  14. [Acute toxicity and bioavailability of nano red elemental selenium].

    PubMed

    Gao, X; Zhang, J; Zhang, L

    2000-01-30

    The reaction ratio of nano red elemental selenium (nanose) with GSH in vitro was one-tenth of that of sodium selenite. Mice were fed with nanose and sodium selenite separately at 50 micrograms/kg BW for 30 days. Both selenium forms could significantly increased Se concentration of blood, liver and activity of blood GSH-Px. Acute toxicity experiment of mice implied that the acute toxicity of nanose was nearly one-seventh of that of sodium selenite. The LD50 for nanose se was 112.98 mg kg BW, and the LD50 for sodium selenite was Se 15.72 mg/kg BW. The acute toxicity of nanose was low for mice.

  15. Uranium Exerts Acute Toxicity by Binding to Pyrroloquinoline Quinone Cofactor

    SciTech Connect

    Michael R. VanEngelen; Robert I. Szilagyi; Robin Gerlach; Brady E. Lee; William A. Apel; Brent M. Peyton

    2011-02-01

    Uranium as an environmental contaminant has been shown to be toxic to eukaryotes and prokaryotes; however, no specific mechanisms of uranium toxicity have been proposed so far. Here a combination of in vivo, in vitro, and in silico studies are presented describing direct inhibition of pyrroloquinoline quinone (PQQ)-dependent growth and metabolism by uranyl cations. Electrospray-ionization mass spectroscopy, UV-vis optical spectroscopy, competitive Ca2+/uranyl binding studies, relevant crystal structures, and molecular modeling unequivocally indicate the preferred binding of uranyl simultaneously to the carboxyl oxygen, pyridine nitrogen, and quinone oxygen of the PQQ molecule. The observed toxicity patterns are consistent with the biotic ligand model of acute metal toxicity. In addition to the environmental implications, this work represents the first proposed molecular mechanism of uranium toxicity in bacteria, and has relevance for uranium toxicity in many living systems.

  16. Serum Zinc Concentrations in Children with Acute Bloody and Watery Diarrhoea

    PubMed Central

    Mahyar, Abolfazl; Ayazi, Parviz; Chegini, Victoria; Sahmani, Mehdi; Oveisi, Sonia; Esmaeily, Shiva

    2015-01-01

    Objectives: The role of zinc in the pathogenesis of diarrhoea is controversial. This study was conducted to compare serum zinc levels in children with acute diarrhoea to those found in healthy children. Methods: This case-control study was carried out at the Qazvin Children’s Hospital in Qazvin, Iran, between July 2012 and January 2013. A total of 60 children with acute diarrhoea (12 children with bloody diarrhoea and 48 children with watery diarrhoea) and 60 healthy children were included. Zinc levels for all subjects were measured using a flame atomic absorption spectrophotometer and data were analysed and compared between groups. Results: Mean serum zinc levels in the patients with acute bloody diarrhoea, acute watery diarrhoea and the control group were 74.1 ± 23.7 μg/dL, 169.4 ± 62.7 μg/dL and 190.1 ± 18.0 μg/dL, respectively (P = 0.01). Hypozincaemia was observed in 50.0% of children with acute bloody diarrhoea and 12.5% of those with acute watery diarrhoea. None of the patients in the control group had hypozincaemia (P = 0.01). Conclusion: Children with acute bloody diarrhoea had significantly reduced serum zinc levels in comparison to healthy children. However, a study with a larger sample size is needed to examine the significance of this trend. PMID:26629379

  17. Toxic effects of zinc on anaerobic microbiota from Zimapán Reservoir (Mexico).

    PubMed

    Vega-López, Armando; Amora-Lazcano, Enriqueta; López-López, Eugenia; Terrón, Oscar; Proal-Nájera, José B

    2007-04-01

    The toxic effects of heavy metals have been extensively documented in different organisms. Nevertheless, a lack of information exists with regard to this topic in the case of autochthonous microorganism communities. The aim of this study was to evaluate the toxic effects of zinc on the anaerobic microorganisms present in the sediment and anoxic water of Zimapán Reservoir (Mexico), with particular focus on dissimilatory sulphate reducing bacteria. In the laboratory, a system of enrichment microcosms was set up with sediment and water from the reservoir. ATP, protein, carbohydrates and lactate and alcohol dehydrogenase activity were determined. The physicochemical parameters of the reservoir were evaluated over the course of one year. Sulphate reduction occurred in the reservoir throughout the year, but was most pronounced at the end of the wet season and during winter. In the field, increases in the rate of sulphate reduction coincided with the lowest levels of total phosphorus and hydrosoluble organic carbon. Zinc enrichment was observed to modify protein and carbohydrate content as well as to affect lactate and alcohol dehydrogenase activity. All responses followed a zinc concentration-response relationship and were dependent on reservoir physicochemical parameters. ATP content was used as a biomarker to evaluate the sublethal toxic effects of zinc. The acceptable threshold concentration of zinc in the aquatic and sediment enrichment microcosms was determined to be 0.06mgZn/L and 711.1mgZn/kg, respectively.

  18. Resolving some practical questions about Daphnia acute toxicity tests

    SciTech Connect

    Barera, Y.; Adams, W.J.

    1981-10-01

    Acute toxicity tests were performed with six age groups of Daphnia magna, ranging from less than or equal to6 h to 216 h, and with five chemicals, selected on the basis of their physical and chemical properties as well as their acute toxicity to D. magna. The age of the daphnids did not significantly alter the 48-h EC/sub 50/ values for the chemicals tested. The maximum difference observed in the 48-h EC/sub 50/ values between the 6-h and 216-h age groups was a factor of 3.9 for linear alkylbenzene sulfonate (LAS). For purposes of standardization, it appears that D. magna up to 48 h of age at the beginning of the test can be used to conduct acute toxicity tests with most chemicals. The results of static acute toxicity tests conducted with butylbenzyl phthalate (BBP) and D. magna in the presence and absence of several commonly used solvents indicate that the acute toxicity of this chemical is not altered by the use of a solvent carrier. The 48-h EC/sub 50/ value for BBP without a solvent was 1.0 mg/L, compared with a range of 1.6 to 2.2 mg/L when acetone, dimethylformamide, ethanol, or triethylene glycol were used as solvent carriers. The acute toxicities of the solvents in the absence of BBP were also determined for D. magna. The values ranged from 9.3 to 52.4 g/L. The results of static acute tests performed with D. magna and BBP in the presence of various concentrations of daphnid foods (algae or trout chow), indicate that the 48-h EC/sub 50/ values increase proportionally with an increase in food concentrations. These results suggest that acute toxicity tests with D. magna should be conducted in the presence of food with chemicals with a high Ksigma if the results are to be used to select the test concentrations for a chronic study with daphnids. The type of food and the concentration used in the acute test should be the same as those used in a chronic test.

  19. Acute toxicity and QSAR of chlorophenols on Daphnia magna

    SciTech Connect

    Devillers, J.; Chambon, P.

    1986-10-01

    Chlorophenols which are released into natural waters from various industrial processes and from agricultural uses have been recognized as a group of chemical substances potentially hazardous to the aquatic environment. Therefore it is important to estimate their toxic impact on biota. Thus, the scope of this research was to obtain acute toxicity data for seventeen chlorophenols towards Daphnia magna and to explore the possibilities of deriving QSAR's (quantitative structure-activity relationship) from the above values.

  20. Degradation and acute toxicity studies of degradable implant materials

    NASA Astrophysics Data System (ADS)

    Taylor, Michelle Suzette

    The present study investigated the acute toxicities of the degradation product components of six degradable polymers, the acute toxicities of nine metallic ions and accelerated degradation of one degradable polymer. Prior to these studies, the effect of the anticipated test conditions on the Microtox acute toxicity assay was determined. It was shown that the Microtox is unaffected by pH of water within the range of 5 to 10 and that the test is unaffected by tris buffer at physiologic pH and concentration. The toxicity and rates of degradation of poly(glycolic acid), PGA; two samples of poly(L-lactic acid), PLLA; samples of different molecular weights, poly(caprolactone), PCL; poly(ortho ester), POE; and poly(hydroxybutyrate-cohydroxyvalerate), PHBV, were compared, along with the toxicity of their degradation product components. The toxic concentrations ranged from 100 muM (lactic acid) to 125,000 muM (pentaerythritol). The degradation product components in order of most toxic to least toxic are lactic acid, caproic acid, glycolic acid, cyclohexanedimethanol, propionic acid, hydroxybutyric acid, 1,6-hexanediol, pentaerythritol dipropionate, pentaerythritol and hydroxyvaleric acid. Acute toxicity was determined for metallic ions in water and buffer. The toxic concentrations ranged from 33 muM (Tisp{4+} in water) to 3,580 muM (Wsp{6+} in buffer). The four most toxic ions in water (Tisp{4+}, Mosp{5+}, Fesp{3+}, Crsp{3+}) caused solution pH to decrease markedly. The six other ions (Vasp{3+}, Cosp{3+}, Alsp{3+,} Tisp{4+} adjusted to pH 6.1, Nisp{2+} and Wsp{6+}) markedly. The six other ions (Vasp{3+}, Cosp{3+}, Alsp{3+}, Tisp{4+} adjusted to pH 6.1, Nisp{2+} and Wsp{6+}) did not appreciably affect pH. In buffer, Alsp{3+}, Nisp{2+}, Wsp{6+} and Vsp{3+} became much less toxic, suggesting formation of complexes. In general the least toxic ions do not create an acid environment and/or do form protective complexes. PHBV has good mechanical properties and, compared with the

  1. Acute toxicity of peracetic acid to fish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peracetic acid (PAA; also called peroxyacetic acid) is a promising new therapeutant for parasites and fungus. It is registered with the U.S. Environmental Protection Agency (EPA) as an antimicrobial compound approved for indoor use on hard, non-porous surfaces. This study determined the acute toxi...

  2. Draft Test Guideline: Gammarid Acute Toxicity Test

    EPA Pesticide Factsheets

    The following draft test guideline is part of a series of test guidelines that have been developed by EPA for use in the testing of pesticides and toxic substances, and the development of test data for submission to the Agency for review.

  3. Draft Test Guideline: Penaeid Acute Toxicity Test

    EPA Pesticide Factsheets

    The following draft test guideline is part of a series of test guidelines that have been developed by EPA for use in the testing of pesticides and toxic substances, and the development of test data for submission to the Agency for review.

  4. Draft Test Guideline: Mysid Acute Toxicity Test

    EPA Pesticide Factsheets

    The following draft test guideline is part of a series of test guidelines that have been developed by EPA for use in the testing of pesticides and toxic substances, and the development of test data for submission to the Agency for review.

  5. Acute and chronic toxicity of veterinary antibiotics to Daphnia magna.

    PubMed

    Wollenberger, L; Halling-Sørensen, B; Kusk, K O

    2000-04-01

    The acute and chronic toxicity of nine antibiotics used both therapeutically and as growth promoters in intensive farming was investigated on the freshwater crustacean Daphnia magna. The effect of the antibiotics metronidazole (M), olaquindox (OL), oxolinic acid (OA), oxytetracycline (OTC), streptomycin (ST), sulfadiazine (SU), tetracycline (TC), tiamulin (TI) and tylosin (TY) was tested in accordance to the ISO (1989) and OECD (1996) standard procedures. The acute toxicities (48-h EC50 value, mg/l) in decreasing order were OA (4.6), TI (40), SU (221), ST (487), TY (680) and OTC (approximately 1000). NOECs were 340 mg/l for TC and 1000 mg/l for M and OL. Toxic effect on reproduction occurred generally at concentrations, which were one order of magnitude below the acute toxic levels. The chronic toxicity (EC50 values, mg/l) in the D. magna reproduction test in decreasing order were TI (5.4), SU (13.7), TC (44.8) and OTC (46.2). The NOECs (mg/l) obtained in the reproduction test with OA, ST, TY and M were 0.38 for OA, 32 for ST, 45 for TY and 250 for M. The observed toxicity of OA to D. magna indicates that this substance, which is a commonly used feed additive in fish farms, has a potential to cause adverse effects on the aquatic environment.

  6. Extrapolation of acute toxicity across bee species.

    PubMed

    Thompson, Helen

    2016-10-01

    In applying cross-species extrapolation safety factors from honeybees to other bee species, some basic principles of toxicity have not been included, for example, the importance of body mass in determining a toxic dose. The present study re-analyzed published toxicity data, taking into account the reported mass of the individuals in the identified species. The analysis demonstrated a shift to the left in the distribution of sensitivity of honeybees relative to 20 other bee species when body size is taken into account, with the 95(th) percentile for contact and oral toxicity reducing from 10.7 (based on μg/individual bee) to 5.0 (based on μg/g bodyweight). Such an approach results in the real drivers of species differences in sensitivity-such as variability in absorption, distribution, metabolism, and excretion in and target-receptor binding-being more realistically reflected in the revised safety factor. Body mass can also be used to underpin the other parameter of first-tier risk assessment, that is, exposure. However, the key exposure factors that cannot be predicted from bodyweight are the effects of ecology and behavior of the different species on exposure to a treated crop. Further data are required to understand the biology of species associated with agricultural crops and the potential consequences of effects on individuals at the levels of the colony or bee populations. This information will allow the development of appropriate higher-tier refinement of risk assessments and testing strategies rather than extensive additional toxicity testing at Tier 1. Integr Environ Assess Manag 2016;12:622-626. © 2015 SETAC.

  7. Toxicity of zinc to fungi, bacteria, and coliphages: influence of chloride ions.

    PubMed Central

    Babich, H; Stotzky, G

    1978-01-01

    A 10 mM concentration of Zn2+ decreased the survival of Escherichia coli; enhanced the survival of Bacillus cereus; did not significantly affect the survival of Pseudomonas aeruginosa, Norcardia corallina, and T1, T7, P1, and phi80 coliphages; completely inhibited mycelial growth of Rhizoctonia solani; and reduced mycelial growth of Fusarium solani, Cunninghamella echinulata, Aspergillus niger, and Trichoderma viride. The toxicity of zinc to the fungi, bacteria, and coliphages was unaffected, lessened, or increased by the addition of high concentrations of NaCl. The increased toxicity of zinc in the presence of high concentrations of NaCl was not a result of a synergistic interaction between Zn2+ and elevated osmotic pressures but of the formation of complex anionic ZnCl species that exerted greater toxicities than did cationic Zn2+. Conversely, the decrease in zinc toxicity with increasing concentrations of NaCl probably reflected the decrease in the levels of Zn2+ due to the formation of Zn-Cl species, which was less inhibitory to these microbes than was Zn2+. A. niger tolerated higher concentrations of zinc in the presence of NaCl at 37 than at 25 degrees C. PMID:736544

  8. [Acute toxicity of bemithyl and bromithyl].

    PubMed

    Bugaeva, L I; Spasov, A A; Verovskiĭ, V E; Iezhitsa, I N

    2000-01-01

    The experiments on rats showed for bemithyl LD50 = 581.48 (350.17-965.57) mg/kg and for bromithyl LD50 = 1750.30 (1463.07-2093.92) mg/kg (males) and 1584.29 (1280.46-1960.22) mg/kg (females). The therapeutic ratios are 4-6 for both drugs, while the toxicity index is 10-15 for bemithyl and 20 <196> 22 for bromithyl. It was established that ergotropic effects prevail in the toxicity of bemithyl administered in the 20-80 mg/kg dose range, while trophotropic effects are dominating at doses above 100 mg/kg. Bromithyl exhibits a dose-dependent trophotropic effect in the entire dose range.

  9. Acute toxicity of pinnatoxins E, F and G to mice.

    PubMed

    Munday, Rex; Selwood, Andrew I; Rhodes, Lesley

    2012-11-01

    The acute toxicities to mice of pinnatoxins E, F and G, members of the cyclic imine group of phycotoxins, by intraperitoneal injection and/or oral administration, have been determined. These substances were all very toxic by intraperitoneal injection, with LD(50) values between 12.7 and 57 μg/kg. Pinnatoxin E was much less toxic by oral administration than by intraperitoneal injection, but this was not the case for pinnatoxin F. The median lethal doses of the latter substance by gavage and by voluntary intake were only 2 and 4 times higher than that by injection. The high oral toxicity of pinnatoxin F raises concerns as to the possibility of adverse effects of this substance in shellfish consumers, although it should be noted that no toxic effects in humans have been recorded with pinnatoxins or with any other compound of the cyclic imine group.

  10. Asparaginase-associated toxicity in children with acute lymphoblastic leukemia.

    PubMed

    Hijiya, Nobuko; van der Sluis, Inge M

    2016-01-01

    Asparaginase is an integral component of multiagent chemotherapy regimens for the treatment of children with acute lymphoblastic leukemia. Positive outcomes are seen in patients who are able to complete their entire prescribed course of asparaginase therapy. Toxicities associated with asparaginase use include hypersensitivity (clinical and subclinical), pancreatitis, thrombosis, encephalopathy, and liver dysfunction. Depending on the nature and severity of the toxicity, asparaginase therapy may be altered or discontinued in some patients. Clinical hypersensitivity is the most common asparaginase-associated toxicity requiring treatment discontinuation, occurring in up to 30% of patients receiving Escherichia coli-derived asparaginase. The ability to rapidly identify and manage asparaginase-associated toxicity will help ensure patients receive the maximal benefit from asparaginase therapy. This review will provide an overview of the common toxicities associated with asparaginase use and recommendations for treatment management.

  11. 40 CFR 797.1050 - Algal acute toxicity test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... acute toxicity of chemical substances and mixtures (“chemicals”) subject to environmental effects test... per volume of nutrient medium or test solution in a specified period of time. (5) Static system means a test container in which the test solution is not renewed during the period of the test. (c)...

  12. 40 CFR 799.9120 - TSCA acute dermal toxicity.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CONTROL ACT (CONTINUED) IDENTIFICATION OF SPECIFIC CHEMICAL SUBSTANCE AND MIXTURE TESTING REQUIREMENTS... mixtures. In order to minimize the need for animal testing, the Agency encourages the review of existing acute toxicity information on mixtures that are substantially similar to the mixture under...

  13. Acute Toxicity of Thionyl Chloride Vapor for Rats

    DTIC Science & Technology

    1984-11-19

    C. and H. V. Davis (1971), The Acute Toxicity of Brief Exposures to Hydrogen Fluoride, Hydrogen Chloride, Nitrogen Dioxide, and Hydrocyanic Acid ...ELECTRODE • • •WAITE ’SOLENOID VALVE P V|TOW ACID -FLEX - ELECTRICAL INTERCONNECTIONS CHART RECORDER Figure 2. Analysis system for total chloride

  14. Acute toxicity of peracetic acid (PAA) to Ichthyophthirius multifiliis theronts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peracetic acid (PAA) is an antimicrobial disinfectant used in agriculture, food processing and medical facilities. It has recently been suggested as a means to control infestations of Ichthyophthirius multifiliis. The purpose of this study was to determine the acute toxicity of two products contai...

  15. Effects of soil type, prepercolation, and ageing on bioaccumulation and toxicity of zinc for the springtail Folsomia candida

    SciTech Connect

    Smit, C.E.; Van Gestel, C.A.M.

    1998-06-01

    Soil properties are a major influence on the bioavailability and toxicity of metals and represent one of the important factors that complicate the extrapolation of results from laboratory tests to field situations. The influence of soil characteristics and way of contamination on the bioaccumulation and toxicity of zinc was investigated for the springtail Folsomia candida, and the applicability of chemical extraction techniques for the prediction of zinc uptake and toxicity was evaluated. Bioaccumulation of zinc in F. candida was related to water-soluble zinc concentrations, and uptake was dependent on the test soil used. Effects of zinc for F. candida could not be fully explained by bioaccumulation. This indicates that the existence of a fixed internal threshold concentration of zinc above which physiological functions are impaired is not likely for F. candida. In freshly contaminated soils, zinc toxicity was related to organic matter and clay content of the soil; however, the use of these soils overestimated the effects of zinc for F. candida by a factor of 5 to 8 compared to a test soil that was subjected to ageing under field conditions for 1.5 years. Equilibration of the zinc contamination by percolating the soils with water before use in the toxicity experiment strongly reduced the difference in zinc toxicity between laboratory-treated and aged soils. Water-soluble concentrations are most appropriate to predict effects of zinc on reproduction of F. candida in soils with unknown contamination histories. For laboratory toxicity tests, it is recommended to percolate soils with water after contamination and to include an equilibration period prior to use to achieve a more realistic exposure situation.

  16. Toxicity evaluation of zinc aluminium levodopa nanocomposite via oral route in repeated dose study

    NASA Astrophysics Data System (ADS)

    Kura, Aminu Umar; Cheah, Pike-See; Hussein, Mohd Zobir; Hassan, Zurina; Tengku Azmi, Tengku Ibrahim; Hussein, Nor Fuzina; Fakurazi, Sharida

    2014-05-01

    Nanotechnology, through nanomedicine, allowed drugs to be manipulated into nanoscale sizes for delivery to the different parts of the body, at the same time, retaining the valuable pharmacological properties of the drugs. However, efficient drug delivery and excellent release potential of these delivery systems may be hindered by possible untoward side effects. In this study, the sub-acute toxicity of oral zinc aluminium nanocomposite with and without levodopa was assessed using the Organization for Economic Co-operation and Development guidelines. No sign or symptom of toxicity was observed in orally treated rats with the nanocomposite at 5 and 500 mg/kg concentrations. Body weight gain, feeding, water intake, general survival and organosomatic index were not significantly different between control and treatment groups. Aspartate aminotransferase (AST) in 500 mg/kg levodopa nanocomposite (169 ± 30 U/L), 5 mg/kg levodopa nanocomposite (172 ± 49 U/L), and 500 mg/kg layered double hydroxides (LDH) nanocomposite (175 ± 25 U/L) were notably elevated compared to controls (143 ± 05 U/L); but the difference were not significant ( p > 0.05). However, the differences in aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio of 500 mg/kg levodopa nanocomposite (0.32 ± 0.12) and 500 mg/kg LDH nanocomposite (0.34 ± 0.12) were statistically significant ( p < 0.05) compared to the control (0.51 ± 0.07). Histology of the liver, spleen and brain was found to be of similar morphology in both control and experimental groups. The kidneys of 500-mg/kg-treated rats with levodopa nanocomposite and LDH nanocomposite were found to have slight inflammatory changes, notably leukocyte infiltration around the glomeruli. The ultra-structure of the neurons from the substantia nigra of nanocomposite-exposed group was similar to those receiving only normal saline. The observed result has suggested possible liver and renal toxicity in orally administered levodopa intercalated

  17. Toxicity evaluation of zinc aluminium levodopa nanocomposite via oral route in repeated dose study

    PubMed Central

    2014-01-01

    Nanotechnology, through nanomedicine, allowed drugs to be manipulated into nanoscale sizes for delivery to the different parts of the body, at the same time, retaining the valuable pharmacological properties of the drugs. However, efficient drug delivery and excellent release potential of these delivery systems may be hindered by possible untoward side effects. In this study, the sub-acute toxicity of oral zinc aluminium nanocomposite with and without levodopa was assessed using the Organization for Economic Co-operation and Development guidelines. No sign or symptom of toxicity was observed in orally treated rats with the nanocomposite at 5 and 500 mg/kg concentrations. Body weight gain, feeding, water intake, general survival and organosomatic index were not significantly different between control and treatment groups. Aspartate aminotransferase (AST) in 500 mg/kg levodopa nanocomposite (169 ± 30 U/L), 5 mg/kg levodopa nanocomposite (172 ± 49 U/L), and 500 mg/kg layered double hydroxides (LDH) nanocomposite (175 ± 25 U/L) were notably elevated compared to controls (143 ± 05 U/L); but the difference were not significant (p > 0.05). However, the differences in aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio of 500 mg/kg levodopa nanocomposite (0.32 ± 0.12) and 500 mg/kg LDH nanocomposite (0.34 ± 0.12) were statistically significant (p < 0.05) compared to the control (0.51 ± 0.07). Histology of the liver, spleen and brain was found to be of similar morphology in both control and experimental groups. The kidneys of 500-mg/kg-treated rats with levodopa nanocomposite and LDH nanocomposite were found to have slight inflammatory changes, notably leukocyte infiltration around the glomeruli. The ultra-structure of the neurons from the substantia nigra of nanocomposite-exposed group was similar to those receiving only normal saline. The observed result has suggested possible liver and renal toxicity in

  18. Acute toxicity of karlotoxins to mice

    PubMed Central

    Place, Allen R.; Munday, R.; Munday, J.S.

    2015-01-01

    Karlotoxins, polyketide derivatives produced by the dinoflagellate Karlodinium veneficum, are associated with fish kills in temperate estuaries world wide. In this study, the acute effects of 3 pure karlotoxin analogs (KmTx 1, KmTx 3 and KmTx 2) have been examined in mice. Transient lethargy and increased respiratory rates were observed soon after dosing with the karlotoxins by intraperitoneal injection, but no deaths were recorded in animals dosed with KmTx 2 at up to 500 μg/kg or with KmTx 1 or KmTx 3 at up to 4000 μg/kg. Animals dosed intraperitoneally with KmTx 1 and KmTx 3 at 4000 μg/kg showed a pronounced decrease in food and water intake, lasting 3–4 days after dosing, accompanied by a significant decrease in body weight. After this time, the lost body weight was regained and the behavior and appearance of the mice remained normal throughout the following 10 day observation period. No effects were seen in mice dosed orally with KmTx 1 or KmTx 3 at a dose of 4000 μg/kg. It is concluded that contamination of seafood if it were to occur with these karlotoxins is unlikely to pose a major risk of acute intoxication in consumers. PMID:25150200

  19. Acute and subchronic dermal toxicity of nanosilver in guinea pig.

    PubMed

    Korani, M; Rezayat, S M; Gilani, K; Arbabi Bidgoli, S; Adeli, S

    2011-01-01

    Silver has been used as an antimicrobial agent for a long time in different forms, but silver nanoparticles (nanosilver) have recently been recognized as potent antimicrobial agents. Although nanosilver is finding diverse medical applications such as silver-based dressings and silver-coated medical devices, its dermal and systemic toxicity via dermal use has not yet been identified. In this study, we analyzed the potential toxicity of colloidal nanosilver in acute and subchronic guinea pigs. Before toxicity assessments, the size of colloidal nanosilver was recorded in sizes <100 nm by X-ray diffraction and transmission electron microscopy. For toxicological assessments, male guinea pigs weighing 350 to 400 g were exposed to two different concentrations of nanosilver (1000 and 10,000 μg/mL) in an acute study and three concentrations of nanosilver (100, 1000, and 10,000 μg/mL) in a subchronic study. Toxic responses were assessed by clinical and histopathologic parameters. In all experimental animals the sites of exposure were scored for any type of dermal toxicity and compared with negative control and positive control groups. In autopsy studies during the acute test, no significant changes in organ weight or major macroscopic changes were detected, but dose-dependent histopathologic abnormalities were seen in skin, liver, and spleen of all test groups. In addition, experimental animals subjected to subchronic tests showed greater tissue abnormalities than the subjects of acute tests. It seems that colloidal nanosilver has the potential to provide target organ toxicities in a dose- and time-dependent manner.

  20. Effect of solcoseryl on antitumour action and acute toxicity of some antineoplastic drugs.

    PubMed

    Danysz, A; Sołtysiak-Pawluczuk, D; Czyzewska-Szafran, H; Jedrych, A; Jastrzebski, Z

    1991-01-01

    The in vivo effect of Solcoseryl on the antitumour activity and acute toxicity of some antineoplastic drugs was examined. It was found that Solcoseryl does not inhibit the antineoplastic effectiveness of the drugs against transplantable P 388 leukaemia in mice. Studies of the effect of Solcoseryl on acute toxicity of selected antineoplastic drugs in mice revealed that the biostimulator could exert a modifying influence. The prior administration of Solcoseryl significantly decreases the acute toxicity of methotrexate but has no effect on acute toxicity of 5-fluorouracil, increases the acute toxicity of bleomycin and vinblastine and has no effect on acute toxicity of methotrexate and mitoxantron. On the other hand, Solcoseryl administered simultaneously with the antineoplastic drugs increases acute toxicity of 5-fluorouracil, bleomycin and mitoxantron. The protective effect of the biostimulator noted exclusively against acute toxicity of 5-fluorouracil was also observed after multiple administration of this anticancer drug.

  1. Cobalt chloride speciation, mechanisms of cytotoxicity on human pulmonary cells, and synergistic toxicity with zinc.

    PubMed

    Bresson, Carole; Darolles, Carine; Carmona, Asuncion; Gautier, Céline; Sage, Nicole; Roudeau, Stéphane; Ortega, Richard; Ansoborlo, Eric; Malard, Véronique

    2013-02-01

    Cobalt is used in numerous industrial sectors, leading to occupational diseases, particularly by inhalation. Cobalt-associated mechanisms of toxicity are far from being understood and information that could improve knowledge in this area is required. We investigated the impact of a soluble cobalt compound, CoCl(2)·6H(2)O, on the BEAS-2B lung epithelial cell line, as well as its impact on metal homeostasis. Cobalt speciation in different culture media, in particular soluble and precipitated cobalt species, was investigated via theoretical and analytical approaches. The cytotoxic effects of cobalt on the cells were assessed. Upon exposure of BEAS-2B cells to cobalt, intracellular accumulation of cobalt and zinc was demonstrated using direct in situ microchemical analysis based on ion micro-beam techniques and analysis after cell lysis by inductively coupled plasma mass spectrometry (ICP-MS). Microchemical imaging revealed that cobalt was rather homogeneously distributed in the nucleus and in the cytoplasm whereas zinc was more abundant in the nucleus. The modulation of zinc homeostasis led to the evaluation of the effect of combined cobalt and zinc exposure. In this case, a clear synergistic increase in toxicity was observed as well as a substantial increase in zinc content within cells. Western blots performed under the same coexposure conditions revealed a decrease in ZnT1 expression, suggesting that cobalt could inhibit zinc release through the modulation of ZnT1. Overall, this study highlights the potential hazard to lung function, of combined exposure to cobalt and zinc.

  2. Sediment acute toxicity testing utilizing short-term bioassays

    SciTech Connect

    Campbell, M.G.

    1991-01-01

    The purpose of this study was to investigate the usefulness of two new bioassays for acute toxicity assessments of sediments. A bacterial bioassay based on inhibition of alpha-glucosidase biosynthesis in Bacillus licheniformis and a 48-hour lethality bioassay employing the benthic cladoceran, Chydorus sphaericus. were evaluated by direct comparisons with standard bioassays, using sediment samples collected from various sites in Florida. This study showed that the bioassay based on inhibition of alpha-glucosidase biosynthesis in Bacillus licheniformis was useful in the acute toxicity screening of sediment elutriates. In regards to Escambia County, Florida samples, the assay was comparable with the Microtox assay and was especially sensitive for samples containing metals. To determine an appropriate procedure for assessing hydrophobic contaminants of sediments in the B. licheniformis bioassay, two extracting procedures were compared. Based on the responses in the Microtox bioassay, shaking sediment samples in methylene chloride produced extracts that were significantly higher in toxicity than extracts obtained by sonication for eight of the ten sediment samples tested. Comparisons of methanol and dimethyl sulfoxide (DMSO) as exchange solvents revealed that there was generally no significant difference between these solvents in terms of toxicity in the Microtox assay. Solvent extracts prepared by shaking and exchanged into methanol showed lower toxicity in the B. licheniformis bioassay than in the Microtox assay. Observed sediment toxicity in both bioassays was expressed in terms of the equivalent dry weight concentration of sediment causing 50% inhibition of the assay organism.

  3. Acute toxicity value extrapolation with fish and aquatic invertebrates.

    PubMed

    Buckler, Denny R; Mayer, Foster L; Ellersieck, Mark R; Asfaw, Amha

    2005-11-01

    Assessment of risk posed by an environmental contaminant to an aquatic community requires estimation of both its magnitude of occurrence (exposure) and its ability to cause harm (effects). Our ability to estimate effects is often hindered by limited toxicological information. As a result, resource managers and environmental regulators are often faced with the need to extrapolate across taxonomic groups in order to protect the more sensitive members of the aquatic community. The goals of this effort were to 1) compile and organize an extensive body of acute toxicity data, 2) characterize the distribution of toxicant sensitivity across taxa and species, and 3) evaluate the utility of toxicity extrapolation methods based upon sensitivity relations among species and chemicals. Although the analysis encompassed a wide range of toxicants and species, pesticides and freshwater fish and invertebrates were emphasized as a reflection of available data. Although it is obviously desirable to have high-quality acute toxicity values for as many species as possible, the results of this effort allow for better use of available information for predicting the sensitivity of untested species to environmental contaminants. A software program entitled "Ecological Risk Analysis" (ERA) was developed that predicts toxicity values for sensitive members of the aquatic community using species sensitivity distributions. Of several methods evaluated, the ERA program used with minimum data sets comprising acute toxicity values for rainbow trout, bluegill, daphnia, and mysids provided the most satisfactory predictions with the least amount of data. However, if predictions must be made using data for a single species, the most satisfactory results were obtained with extrapolation factors developed for rainbow trout (0.412), bluegill (0.331), or scud (0.041). Although many specific exceptions occur, our results also support the conventional wisdom that invertebrates are generally more sensitive to

  4. Acute toxicity value extrapolation with fish and aquatic invertebrates

    USGS Publications Warehouse

    Buckler, Denny R.; Mayer, Foster L.; Ellersieck, Mark R.; Asfaw, Amha

    2005-01-01

    Assessment of risk posed by an environmental contaminant to an aquatic community requires estimation of both its magnitude of occurrence (exposure) and its ability to cause harm (effects). Our ability to estimate effects is often hindered by limited toxicological information. As a result, resource managers and environmental regulators are often faced with the need to extrapolate across taxonomic groups in order to protect the more sensitive members of the aquatic community. The goals of this effort were to 1) compile and organize an extensive body of acute toxicity data, 2) characterize the distribution of toxicant sensitivity across taxa and species, and 3) evaluate the utility of toxicity extrapolation methods based upon sensitivity relations among species and chemicals. Although the analysis encompassed a wide range of toxicants and species, pesticides and freshwater fish and invertebrates were emphasized as a reflection of available data. Although it is obviously desirable to have high-quality acute toxicity values for as many species as possible, the results of this effort allow for better use of available information for predicting the sensitivity of untested species to environmental contaminants. A software program entitled “Ecological Risk Analysis” (ERA) was developed that predicts toxicity values for sensitive members of the aquatic community using species sensitivity distributions. Of several methods evaluated, the ERA program used with minimum data sets comprising acute toxicity values for rainbow trout, bluegill, daphnia, and mysids provided the most satisfactory predictions with the least amount of data. However, if predictions must be made using data for a single species, the most satisfactory results were obtained with extrapolation factors developed for rainbow trout (0.412), bluegill (0.331), or scud (0.041). Although many specific exceptions occur, our results also support the conventional wisdom that invertebrates are generally more

  5. Avoidance response of sediment living amphipods to zinc pyrithione as a measure of sediment toxicity.

    PubMed

    Eriksson Wiklund, Ann-Kristin; Börjesson, Therese; Wiklund, Stig Johan

    2006-01-01

    An avoidance test was developed using non-cultured individuals of the sediment dwelling amphipod Monoporeia affinis. As test substance we used zinc pyrithione, an antifouling agent and a common shampoo ingredient. The toxicity to Daphnia and fish is well known but sediment toxicity of this very hydrophobic compound is less known. The preference of juvenile M. affinis was tested in jars, each including 12 petri dishes. In each replicate, half of the petri dishes contained sediment mixed with six concentrations ranging from 0 to 10microg zinc pyrithione per L sediment and half of the petri dishes contained the corresponding sediment-substance mixture plus an extra food addition. The amphipods significantly avoided petri dishes with the three highest concentrations of zinc pyrithione and the calculated EC(50) was 9.65microgL(-1) sediment. No difference in mortality was observed between concentrations. Using the avoidance behaviour in sediment toxicity testing is a simple and cost-effective screening for toxicants.

  6. Acute toxicity of cyanogen chloride to Daphnia magna

    SciTech Connect

    Kononen, D.W.

    1988-09-01

    The destruction of cyanide in waste waters by chlorination has been shown to result in the formation of the extremely toxic compound, cyanogen chloride. Industrial cyanide-containing waste waters may be treated by a batch chlorination process under highly alkaline conditions prior to being discharged into a receiving water systems. Alternatively, if the concentration of cyanide is relatively low, and such waste waters may be diverted to municipal waste treatment facilities where they may be subjected to a process of chlorination which may not be sufficient for the complete oxidative destruction of the available cyanide. Although a large body of literature exists concerning the toxicity of HCN and metallic cyanide compounds to aquatic organisms, there is a comparative scarcity of information concerning cyanogen chloride toxicity. This study was designed to determine the acute toxicity of CNCl to Daphnia magna neonates under static bioassay conditions.

  7. Acute toxicity of 50 metals to Daphnia magna.

    PubMed

    Okamoto, Akira; Yamamuro, Masumi; Tatarazako, Norihisa

    2015-07-01

    Metals are essential for human life and physiological functions but may sometimes cause disorders. Therefore, we conducted acute toxicity testing of 50 metals in Daphnia magna: EC50s of seven elements (Be, Cu, Ag, Cd, Os, Au and Hg) were < 100 µg l(-1) ; EC50s of 13 elements (Al, Sc, Cr, Co, Ni, Zn, Se, Rb, Y, Rh, Pt, Tl and Pb) were between 100 and 1000 µg l(-1) ; EC50s of 14 elements (Li, V, Mn, Fe, Ge, As, In, Sn, Sb, Te, Cs, Ba, W and Ir) were between 1,001 and 100,000 µg l(-1) ; EC50s of six elements (Na, Mg, K, Ca, Sr and Mo) were > 100,000 µg l(-1) ; and. 7 elements (Ti, Zr, Bi, Nb, Hf, Re and Ta) did not show EC50 at the upper limit of respective aqueous solubility, and EC50s were not obtained. Ga, Ru and Pd adhered to the body of D. magna and physically retarded the movement of D. magna. These metals formed hydroxides after adjusting the pH. Therefore, here, we distinguished this physical effect from the physiological toxic effect. The acute toxicity results of 40 elements obtained in this study were not correlated with electronegativity. Similarly, the acute toxicity results of metals including the rare metals were also not correlated with first ionization energy, atomic weight, atomic number, covalent radius, atomic radius or ionic radius.

  8. Evaluation of the effect of reactive sulfide on the acute toxicity of silver (I) to Daphnia magna. Part 2: toxicity results.

    PubMed

    Bianchini, Adalto; Bowles, Karl C; Brauner, Colin J; Gorsuch, Joseph W; Kramer, James R; Wood, Chris M

    2002-06-01

    The protective effect of reactive sulfide against AgNO3 toxicity to Daphnia magna neonates was studied. Acute (48-h) toxicity tests were performed in the absence (<5 nM) and presence of low (approximately 25 nM) and high (approximately 250 nM) concentrations of zinc sulfide clusters under oxic conditions. In both the presence and the absence of sulfide, lower mean lethal concentration (LC50) values were observed when measured as opposed to nominal silver concentrations were used in calculations. This reflected the fact that measured total silver concentrations were lower than nominal concentrations due to losses of silver from solution observed during the experiment. High concentration (approximately 250 nM) of sulfide completely protected against toxicity up to the highest silver concentration tested (2 microg/L [19 nM]) with measured silver data. In the presence of environmentally realistic levels of sulfide (approximately 25 nM) in receiving waters, acute silver toxicity was reduced by about 5.5-fold. However, when filtered (0.45 microm) silver concentrations alone were considered, toxicity (48-h LC50) was similar in the absence (0.22 microg/L) and presence (0.28 microg/L) of sulfide. The difference between measured total and filtered silver was attributed to chemisorption of the metal sulfide onto the membrane filter and provides evidence that the toxic fraction of silver is that which is unbound to sulfide. Accumulation of silver was greater in daphnids exposed to silver in the presence of sulfide than in its absence, even though a toxic effect was not observed under these conditions. In this case, silver appears to be incorporated by daphnids rather than merely adsorbed on the surface. Our results point out the need to incorporate sulfide into the acute biotic ligand model and to assess its potentially large role in preventing chronic toxicity.

  9. Bioavailability and toxicity of dietborne copper and zinc to fish

    USGS Publications Warehouse

    Clearwater, Susan J.; Farag, Aida M.; Meyer, J.S.

    2002-01-01

    To date, most researchers have used dietborne metal concentrations rather than daily doses to define metal exposure and this has resulted in contradictory data within and between fish species. It has also resulted in the impression that high concentrations of dietborne Cu and Zn (e.g.>900 mg kg−1 dry diet) are relatively non-toxic to fish. We re-analyzed existing data using rations and dietborne metal concentrations and used daily dose, species and life stage to define the toxicity of dietborne Cu and Zn to fish. Partly because of insufficient information we were unable to find consistent relationships between metal toxicity in laboratory-prepared diets and any other factor including, supplemented metal compound (e.g. CuSO4 or CuCl2), duration of metal exposure, diet type (i.e. practical, purified or live diets), or water quality (flow rates, temperature, hardness, pH, alkalinity). For laboratory-prepared diets, dietborne Cu toxicity occurred at daily doses of >1 mg kg−1 body weight d−1 for channel catfish (Ictalurus punctatus), 1–15 mg kg−1 body weight d−1 (depending on life stage) for Atlantic salmon (Salmo salar) and 35–45 mg kg−1 body weight d−1 for rainbow trout (Oncorhynchus mykiss). We found that dietborne Zn toxicity has not yet been demonstrated in rainbow trout or turbot (Scophthalmus maximus) probably because these species have been exposed to relatively low doses of metal (<90 mg kg−1 body weight d−1) and effects on growth and reproduction have not been analyzed. However, daily doses of 9–12 mg Zn kg−1 body weight d−1 in laboratory-prepared diets were toxic to three other species, carp Cyprinus carpio, Nile tilapia Oreochromis niloticus, and guppy Poecilia reticulata. Limited research indicates that biological incorporation of Cu or Zn into a natural diet can either increase or decrease metal bioavailability, and the relationship between bioavailability and toxicity remains unclear. We have resolved the contradictory data

  10. Mechanisms of zinc toxicity in the galaxiid fish, Galaxias maculatus.

    PubMed

    McRae, Nicole K; Gaw, Sally; Glover, Chris N

    2016-01-01

    Zinc (Zn) is an essential metal, which is ubiquitous in aquatic environments occurring both naturally, and through anthropogenic inputs. This study investigated impacts of sub-lethal Zn exposure in the galaxiid fish Galaxias maculatus. Known as inanga, this amphidromous fish is widespread throughout the Southern hemisphere, but to date almost nothing is known regarding its sensitivity to elevated environmental metals. Fish were exposed to environmentally-relevant concentrations of Zn (control, 8, 270 and 1000μgL(-1)) over 96h. End-points measured included those relating to ionoregulatory disturbance (whole body calcium and sodium influx), oxygen consumption (respirometry), oxidative stress (catalase activity and lipid peroxidation) and whole body accumulation of Zn. Zn exposure caused increases in catalase activity and lipid peroxidation, but only at the highest exposure level tested. Zn also significantly inhibited calcium influx, but stimulated sodium influx, at 1000μgL(-1). The sub-lethal changes induced by Zn exposure in inanga appear to be conserved relative to other, better-studied species. These data are the first to explore the sensitivity of juvenile galaxiid fish to Zn, information that will be critical to ensuring adequate environmental protection of this important species.

  11. Foraging, feeding, and reproduction on silica substrate: Increased waterborne zinc toxicity to the estuarine epibenthic amphipod Melita plumulosa.

    PubMed

    Mann, Reinier M; Hyne, Ross V; Ascheri, Laure M E

    2011-07-01

    Artificial substrates consisting of fine milled silica with or without α-cellulose were evaluated for their capacity to support survival, growth, and fecundity in the amphipod Melita plumulosa. There were no significant differences in the survival and fecundity of adult amphipods maintained for up to 13 d on natural sediment, silica-only, or silica/α-cellulose substrate when fed two algal foods, Sera micron and Rotiselco-ALG. However, growth among juveniles maintained on the silica/α-cellulose mixture was significantly inhibited over 14 d compared with natural sediment. Addition of a microencapsulated shrimp feed, Frippak, to the algal foods improved juvenile growth over 28 d but still did not match the nutritive value of natural sediment. Fine silica without cellulose was subsequently used in acute and reproductive toxicity tests with waterborne zinc. With food, a 10-d median lethal concentration (LC50) of 140 µg Zn/L and a 10-d no-effect concentration (NEC) of 80 µg Zn/L were obtained for juvenile survival on silica. In contrast, a 10-d LC50 of 200 µg Zn/L and a 10-d NEC of 180 µg Zn/L were obtained for juveniles in water-only exposures. Similarly, exposure of adult females to Zn without food on silica compared with water-only exposures gave 10-d LC50s of 380 and 490 µg Zn/L and 10-d NECs of 130 and 370 µg Zn/L, respectively. The reproduction toxicity test indicated significant adult mortality at 92 µg Zn/L and significantly reduced fecundity at 22 µg Zn/L. We surmised that the toxicity of waterborne zinc to M. plumulosa increased when maintained on nutrient-depleted silica compared with water-only exposure because of increased energy expended through foraging, in concert with the likely increased exposure to Zn via the digestive tract and the gills.

  12. Acute toxicity of saline produced waters to marine organisms

    SciTech Connect

    Pillard, D.A.; Evans, J.M.; DuFresne, D.L.

    1996-11-01

    Produced waters from oil and gas drilling operations are typically very saline, and may cause acute toxicity to marine organisms due imbalances as well as to an excess or deficiency of to osmotic specific common ions. In order to better understand the relationship between toxicity and ion concentration, laboratory toxicity tests were conducted using mysid shrimp (Mysidopsis bahia), sheepshead minnow, (Cyprinodon variegatus), and inland silvemide (Menidia beryllina). For each species the ionic concentration of standard laboratory water was proportionally increased or decreased to produce test solutions with a range of salinities. Individual ions (sodium, potassium, calcium, magnesium, strontium, chloride, bromide, sulfate, bicarbonate, and borate) were also manipulated to examine individual ion toxicity. Organisms were exposed for 48 hours. The three test species differ in their tolerance of salinity. Mysid shrimp show a marked decrease in survival at salinities less than approximately 5 ppt. Both fish species tolerated low salinity water, however, silversides were less tolerant of saline waters (salinity greater than 40 ppt). There were also significant differences in the responses of the organisms to different ions. The results show that salinity of the test solution may play an important role in the responses of the organisms to produced water effluent. Predictable toxicity/ion relationships developed in this study can be used to estimate whether toxicity in produced water is a result of common ions, salinity, or some other unknown toxicant.

  13. Protection against oxaliplatin acute neurosensory toxicity by venlafaxine.

    PubMed

    Durand, Jean-Philippe; Brezault, Catherine; Goldwasser, François

    2003-07-01

    Venlafaxine (Effexor; Wyeth Lederlé) has previously shown therapeutic effects for the management of chronic and neuropathic pains. We report here the efficacy of venlafaxine upon acute neurosensory symptoms secondary to oxaliplatin toxicity. A dose of 50 mg of venlafaxine was given orally at the beginning of the oxaliplatin infusion. Patients did not experience any or very low paresthesias, even in the cold. As the results were very dramatic and reproducible, we propose that venlafaxine may be of use in the daily management of oxaliplatin-related neurosensory toxicity.

  14. Acute toxicity of nickel nanoparticles in rats after intravenous injection

    PubMed Central

    Magaye, Ruth R; Yue, Xia; Zou, Baobo; Shi, Hongbo; Yu, Hongsheng; Liu, Kui; Lin, Xialu; Xu, Jin; Yang, Cui; Wu, Aiguo; Zhao, Jinshun

    2014-01-01

    This study was carried out to add scientific data in regard to the use of metallic nanoparticles in nanomedicine. The acute toxicity of nickel (Ni) nanoparticles (50 nm), intravenously injected through the dorsal penile vein of Sprague Dawley rats was evaluated in this study. Fourteen days after injection, Ni nanoparticles induced liver and spleen injury, lung inflammation, and caused cardiac toxicity. These results indicate that precautionary measures should be taken with regard to the use of Ni nanoparticles or Ni compounds in nanomedicine. PMID:24648736

  15. In vitro toxicity of zinc oxide nanoparticles: a review

    NASA Astrophysics Data System (ADS)

    Pandurangan, Muthuraman; Kim, Doo Hwan

    2015-03-01

    The toxic effect of ZnO nanoparticles is due to their solubility. ZnO nanoparticles dissolve in the extracellular region, which in turn increases the intracellular [Zn2+] level. The mechanism for increased intracellular [Zn2+] level and ZnO nanoparticles dissolution in the medium is still unclear. Cytotoxicity, increased oxidative stress, increased intracellular [Ca2+] level, decreased mitochondrial membrane potential, and interleukin-8 productions occur in the BEAS-2B bronchial epithelial cells and A549 alveolar adenocarcinoma cells following the exposure of ZnO nanoparticles. Confluent C2C12 cells are more resistant to ZnO nanoparticles compared to the sparse monolayer. Loss of 3T3-L1 cell viability, membrane leakage, and morphological changes occurs due to exposure of ZnO nanoparticles. ZnO nanoparticle induces cytotoxicity and mitochondrial dysfunction in RKO colon carcinoma cells. The occurrence of apoptosis, increased ROS level, reduced mitochondrial activity and formation of tubular intracellular structures are reported following exposure of ZnO nanoparticles in skin cells. Macrophages, monocytes, and dendritic cells are affected by ZnO nanoparticles. In addition, genotoxicity is also induced. The present review summarizes the literature on in vitro toxicity of ZnO nanoparticles (10-100 nm) on various cell lines.

  16. Development of a general baseline toxicity QSAR model for the fish embryo acute toxicity test.

    PubMed

    Klüver, Nils; Vogs, Carolina; Altenburger, Rolf; Escher, Beate I; Scholz, Stefan

    2016-12-01

    Fish embryos have become a popular model in ecotoxicology and toxicology. The fish embryo acute toxicity test (FET) with the zebrafish embryo was recently adopted by the OECD as technical guideline TG 236 and a large database of concentrations causing 50% lethality (LC50) is available in the literature. Quantitative Structure-Activity Relationships (QSARs) of baseline toxicity (also called narcosis) are helpful to estimate the minimum toxicity of chemicals to be tested and to identify excess toxicity in existing data sets. Here, we analyzed an existing fish embryo toxicity database and established a QSAR for fish embryo LC50 using chemicals that were independently classified to act according to the non-specific mode of action of baseline toxicity. The octanol-water partition coefficient Kow is commonly applied to discriminate between non-polar and polar narcotics. Replacing the Kow by the liposome-water partition coefficient Klipw yielded a common QSAR for polar and non-polar baseline toxicants. This developed baseline toxicity QSAR was applied to compare the final mode of action (MOA) assignment of 132 chemicals. Further, we included the analysis of internal lethal concentration (ILC50) and chemical activity (La50) as complementary approaches to evaluate the robustness of the FET baseline toxicity. The analysis of the FET dataset revealed that specifically acting and reactive chemicals converged towards the baseline toxicity QSAR with increasing hydrophobicity. The developed FET baseline toxicity QSAR can be used to identify specifically acting or reactive compounds by determination of the toxic ratio and in combination with appropriate endpoints to infer the MOA for chemicals.

  17. An evaluation of acute toxicity of colloidal silver nanoparticles.

    PubMed

    Maneewattanapinyo, Pattwat; Banlunara, Wijit; Thammacharoen, Chuchaat; Ekgasit, Sanong; Kaewamatawong, Theerayuth

    2011-11-01

    Tests for acute oral toxicity, eye irritation, corrosion and dermal toxicity of colloidal silver nanoparticles (AgNPs) were conducted in laboratory animals following OECD guidelines. Oral administration of AgNPs at a limited dose of 5,000 mg/kg produced neither mortality nor acute toxic signs throughout the observation period. Percentage of body weight gain of the mice showed no significant difference between control and treatment groups. In the hematological analysis, there was no significant difference between mice treated with AgNPs and controls. Blood chemistry analysis also showed no differences in any of the parameter examined. There was neither any gross lesion nor histopathological change observed in various organs. The results indicated that the LD(50) of colloidal AgNPs is greater than 5,000 mg/kg body weight. In acute eye irritation and corrosion study, no mortality and toxic signs were observed when various doses of colloidal AgNPs were instilled in guinea pig eyes during 72 hr observation period. However, the instillation of AgNPs at 5,000 ppm produced transient eye irritation during early 24 hr observation time. No any gross abnormality was noted in the skins of the guinea pigs exposed to various doses of colloidal AgNPs. In addition, no significant AgNPs exposure relating to dermal tissue changes was observed microscopically. In summary, these findings of all toxicity tests in this study suggest that colloidal AgNPs could be relatively safe when administered to oral, eye and skin of the animal models for short periods of time.

  18. Acute and chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures

    USGS Publications Warehouse

    Ingersoll, Christopher G.; Contributions by Wang, Ning; Calfee, Robin D.; Beahan, Erinn; Brumbaugh, William G.; Dorman, Rebecca A.; Hardesty, Doug K.; Kunz, James L.; Little, Edward E.; Mebane, Christopher A.; Puglis, Holly J.

    2014-01-01

    White sturgeon (Acipenser transmontanus) are experiencing poor recruitment in the trans boundary reach of the upper Columbia River in eastern Washington State. Limited toxicity data indicated that early life stages of white sturgeon are sensitive to metals. In acute 4-day (d) exposures with larval white sturgeon, previous studies have reported that the 4-day median lethal concentrations (LC50) based on biotic ligand model (BLM) normalization for copper were below the U.S. Environmental Protection Agency national recommended acute water-quality criterion. In previously published chronic 66-d exposures starting with newly fertilized eggs of white sturgeon, 20-percent lethal effect concentrations (LC20s) for copper, cadmium, or zinc generally were within a factor of two of the chronic values of the most sensitive fish species in the databases of the U.S. Environmental Protection Agency water-quality criteria (WQC) for the three metals. However, there were some uncertainties in the chronic exposures previously performed with white sturgeon, including (1) low control survival (37 percent), (2) more control fish tested in each replicate compared to other treatments, (3) limited replication of treatments (n=2), (4) lack of reported growth data (such as dry weight), and (5) wide dilution factors for exposure concentrations (6- to 8-fold dilutions). The U.S. Environmental Protection Agency concluded that additional studies are needed to generate more toxicity data to better define lethal and sublethal toxicity thresholds for metals for white sturgeon. The objective of the study was to further evaluate the acute and chronic toxicity of cadmium, copper, lead, or zinc to early life stages of white sturgeon in water-only exposures. Toxicity tests also were performed with commonly tested rainbow trout (Oncorhynchus mykiss) under similar test conditions to determine the relative sensitivity between white sturgeon and rainbow trout to these metals. Toxicity data generated from

  19. Evaluation of acute toxicity potential of water hyacinth leaves.

    PubMed

    Wu, Wenbiao; Guo, Xiaoguang; Huang, Mingliang

    2014-06-01

    Although higher protein yield per hectare of water hyacinth than that of soy, high protein content of its leaves and good essential amino acid pattern have been proven, its dietary toxicity for human or animal consumption has not yet been evaluated. Therefore, the acute toxicity of water hyacinth leaves has been evaluated by an animal feeding test. The concentrations of common toxic metals including cadmium, lead, platinum, palladium, tin, mercury, barium, silver, stibium and aluminum in the water hyacinth leaf powder (WHLP) used for the animal feeding test were within their maximum limits in food additives as reported by the World Health Organization. The median lethal dose (LD50) of WHLP was more than 16 g kg(-1) body weight. In the study, after feeding for 7 and 28 days, the body weight of all the mice increased. The results of hematological analysis, clinical biochemical analysis, histopathological evaluation, general dissection or investigations of internal organs, appearance and behavior observations did not indicate any adverse effects from the diet containing WHLP. It is therefore concluded that water hyacinth leaves are not acutely toxic.

  20. Aquatic acute toxicity assessments of molybdenum (+VI) to Daphnia magna.

    PubMed

    Wang, Chi-Wei; Liang, Chenju; Yeh, Hui-Ju

    2016-03-01

    Generally, molybdenum (Mo) metals in the environment are very rare, but wastewater discharges from industrial processes may contain high concentrations of Mo, which has the potential to contaminate water or soil if not handled properly. In this study, the impact of three common compounds of hexavalent Mo (sodium molybdate (Na2MoO4‧2H2O), ammonium molybdate ((NH4)6Mo7O24‧4H2O) and molybdenum trioxide (MoO3)) in an aquatic system were assessed based on 48-h exposure acute toxicity to Daphnia magna (D. magna). The LC50 toxicities for associated conjugate ions including Na(+), Cl(-), SO4(2-), and NH4(+) were determined. Furthermore, the LC50 values for the three forms of hexavalent Mo were determined, and the acute toxicities of the Mo forms were found to follow the order: (NH4)6Mo7O24‧4H2O > MoO3 > Na2MoO4‧2H2O in solution. (NH4)6Mo7O24‧4H2O exhibited the lowest LC50 of 43.3 mg L(-1) (corresponding to 23.5 mg Mo L(-1)) among the three molybdenum salts. The research confirmed that the toxicity of molybdenum in the aquatic system is highly dependent on the form of molybdenum salts used, and is also associated with the influence of the background water quality.

  1. Acute toxicity testing in cultures of mouse neuroblastoma cells.

    PubMed

    Walum, E; Peterson, A

    1983-01-01

    Cultured mouse neuroblastoma cells (C1300) may be used as models for nerve cells since they have a number of properties in common with their normal counterparts in vivo. In order to test the possibility of using C1300 cells as alternative to experimental animals when testing for acute toxicity, cells (clone 41A3) were exposed to a number of common chemicals (CH3HgCl, CdCl2,HgCl2 ppDDT, n-butanol, benzene, dioxan, n-propanol, aceton and t-butanol). The toxic effect was quantified by measuring the degree of cell detachment in the cultures. The concentrations of chemicals that caused 25% of the total cell number to detach (TD25) were used for comparison with LD50 values. In spite of the very simplified situation in culture, where the toxicity of a substance is little or not at all influenced by factors like penetration, storage, metabolism and excretion a good correlation (corr. coeff. 0,98) was obtained between TD25 values and LD50 values. Good correlations between in vitro and in vivo tests have also been reported by others. One possible explanation to these findings could be simplified in vivo toxicokinetics of these substances when tested in high doses for general effects like animal death. If so, simple in vitro tests may be used for predicting acute toxicity of certain groups of substances.

  2. Acute and delayed toxicities of total body irradiation

    SciTech Connect

    Deeg, H.J.

    1983-12-01

    Total body irradiation is being used with increasing frequency for the treatment of lymphopoietic malignancies and in preparation for marrow transplantation. Acute toxicities include reversible gastroeneritis, mucositis, myelosuppression alopecia. As the success of treatment improves and more patients become long-term survivors, manifestations of delayed and chronic toxicity become evident. These include impairment of growth and development, gonadal failure and sterility, cataract formation and possibly secondary malignancies. The contribution of total body irradiation to the development of pneumonitis and pulmonary fibrosis is still poorly understood. Some of these changes are reversible or correctable, whereas others are permanent. Nevertheless, until equally effective but less toxic regimens become available, total body irradiation appears to be the treatment of choice to prepare patients with leukemia for marrow transplantation.

  3. CARDIOVASCULAR INJURY FROM ACUTE AND REPEATED EXPOSURE TO PARTICULATE MATTER (PM): POTENTIAL ROLE OF ZINC

    EPA Science Inventory

    CARDIOVASCULAR INJURY FROM ACUTE AND REPEATED EXPOSURE TO PARTICULATE MATTER (PM): POTENTIAL ROLE OF ZINC. UP Kodavanti, MC Schladweiler, AD Ledbetter, RH Jaskot, PS Gilmour, DC Christiani, WP Watkinson, DL Costa, JK McGee, A Nyska. NHEERL, USEPA, RTP, NC; CEMALB, UNC, Chapel Hil...

  4. Zinc

    MedlinePlus

    ... pill" to help remove excess water from the body. Another effect of amiloride (Midamor) is that it can increase the amount of zinc in the body. Taking zinc supplements with amiloride (Midamor) might cause ...

  5. Quantification of toxic and inhibitory impact of copper and zinc on mixed cultures of sulfate-reducing bacteria.

    PubMed

    Utgikar, Vivek P; Tabak, Henry H; Haines, John R; Govind, Rakesh

    2003-05-05

    The adverse effects of copper and zinc on an acetate-utilizing mixed cultures of sulfate-reducing bacteria (SRB) at concentrations below the toxic concentration (minimum metal concentration at which no sulfate reduction is observed) are reported in this paper. Mathematical models were developed to incorporate the toxic and inhibitory effects (defined as the reduction in bacterial population upon exposure to the metal and the decrease in the metabolic rate of sulfate reduction by the SRB, respectively) into the sulfate-reduction biokinetics. The characteristic toxicity and inhibition constants were obtained from the measurements of bacterial populations and dissolved metal concentrations in serum bottle studies conducted at 35 degrees C and pH 6.6. Both copper and zinc had toxic and inhibitory effects on SRB. The toxicity constants for copper and zinc were 10.6 and 2.9 mM(-1), respectively, indicating that exposure to copper resulted in a higher mortality of SRB than did exposure to zinc. The values of the inhibition constants were found to be 17.9 +/- 2.5 and 25.2 +/- 1.0 mM(-1) for copper and zinc, respectively. This implies that dissolved zinc was slightly more inhibitory to SRB than copper. The models presented in the paper can be used to predict the response of a sulfate-reduction bioreactor to heavy metals during acid mine drainage treatment.

  6. Proteus mirabilis alleviates zinc toxicity by preventing oxidative stress in maize (Zea mays) plants.

    PubMed

    Islam, Faisal; Yasmeen, Tahira; Riaz, Muhammad; Arif, Muhammad Saleem; Ali, Shafaqat; Raza, Syed Hammad

    2014-12-01

    Plant-associated bacteria can have beneficial effects on the growth and health of their host. However, the role of plant growth promoting bacteria (PGPR), under metal stress, has not been widely investigated. The present study investigated the possible mandatory role of plant growth promoting rhizobacteria in protecting plants from zinc (Zn) toxicity. The exposure of maize plants to 50µM zinc inhibited biomass production, decreased chlorophyll, total soluble protein and strongly increased accumulation of Zn in both root and shoot. Similarly, Zn enhanced hydrogen peroxide, electrolyte leakage and lipid peroxidation as indicated by malondaldehyde accumulation. Pre-soaking with novel Zn tolerant bacterial strain Proteus mirabilis (ZK1) isolated zinc (Zn) contaminated soil, alleviated the negative effect of Zn on growth and led to a decrease in oxidative injuries caused by Zn. Furthermore, strain ZK1 significantly enhanced the activities of catalase, guaiacol peroxidase, superoxide dismutase and ascorbic acid but lowered the Proline accumulation in Zn stressed plants. The results suggested that the inoculation of Zea mays plants with P. mirabilis during an earlier growth period could be related to its plant growth promoting activities and avoidance of cumulative damage upon exposure to Zn, thus reducing the negative consequences of oxidative stress caused by heavy metal toxicity.

  7. Acclimation-induced changes in the toxicity of zinc and cadmium to rainbow trout

    SciTech Connect

    Stubblefield, W.A.; Steadman, B.L.; La Point, T.W.; Bergman, H.L.

    1999-12-01

    Adults and juvenile rainbow trout exposed for 21 d to sublethal levels of zinc or cadmium exhibited significant changes in their respective incipient lethal levels (ILL). Acclimation resulted in exposure-dependent changes in both tolerance (ILL concentration) and resistance (time to ILL) in both size classes of fish for each metal. The ILLs for adult rainbow trout exposed to zinc increased from 695 {micro}g/L at 131 h for nonacclimated fish to 2,025 {micro}/L at 168 h for fish previously exposed to 0.5 ILL (324 {micro}g/L zinc). The ILLs for cadmium-exposed fish increased from 6 {micro}g/L at 187 h for nonacclimated fish to 122 {micro}g/L at 266 h for fish acclimated to 0.5 ILL (10.2 {micro}g/L cadmium). Similar, although somewhat less dramatic, acclimation responses were observed for juveniles with both zinc and cadmium. Juveniles were found to be approximately three times less sensitive to the toxic effects of the metals than were adult fish.

  8. Acute oral toxicities of wildland fire control chemicals to birds

    USGS Publications Warehouse

    Vyas, N.B.; Spann, J.W.; Hill, E.F.

    2009-01-01

    Wildland fire control chemicals are released into the environment by aerial and ground applications to manage rangeland, grassland, and forest fires. Acute oral 24 h median lethal dosages (LD50) for three fire retardants (Fire-Trol GTS-R?, Phos-Chek D-75F?, and Fire-Trol LCG-R?) and two Class A fire suppressant foams (Silv-Ex? and Phos-Chek WD881?) were estimated for northern bobwhites, Colinus virginianus, American kestrels, Falco sparverius, and red-winged blackbirds, Agelaius phoeniceus. The LD50s of all chemicals for the bobwhites and red-winged blackbirds and for kestrels dosed with Phos-Chek WD881? and Silv-Ex? were above the predetermined 2000 mg chemical/kg body mass regulatory limit criteria for acute oral toxicity. The LD50s were not quantifiable for kestrels dosed with Fire-Trol GTS-R?, Phos-Chek D-75F?, and Fire-Trol LCG-R? because of the number of birds which regurgitated the dosage. These chemicals appear to be of comparatively low order of acute oral toxicity to the avian species tested.

  9. Determination of acute oral toxicity of flumethrin in honey bees.

    PubMed

    Oruc, H H; Hranitz, J M; Sorucu, A; Duell, M; Cakmak, I; Aydin, L; Orman, A

    2012-12-01

    Flumethrin is one of many pesticides used for the control and treatment of varroatosis in honey bees and for the control of mosquitoes and ticks in the environment. For the control of varroatosis, flumethrin is applied to hives formulated as a plastic strip for several weeks. During this time, honey bees are treated topically with flumethrin, and hive products may accumulate the pesticide. Honey bees may indirectly ingest flumethrin through hygienic behaviors during the application period and receive low doses of flumethrin through comb wax remodeling after the application period. The goal of our study was to determine the acute oral toxicity of flumethrin and observe the acute effects on motor coordination in honey bees (Apis mellifera anatoliaca). Six doses (between 0.125 and 4.000 microg per bee) in a geometric series were studied. The acute oral LD50 of flumethrin was determined to be 0.527 and 0.178 microg per bee (n = 210, 95% CI) for 24 and 48 h, respectively. Orally administered flumethrin is highly toxic to honey bees. Oral flumethrin disrupted the motor coordination of honey bees. Honey bees that ingested flumethrin exhibited convulsions in the antennae, legs, and wings at low doses. At higher doses, partial and total paralysis in the antennae, legs, wings, proboscises, bodies, and twitches in the antennae and legs were observed.

  10. The pattern of acute toxic nephropathy in Ife, Nigeria.

    PubMed

    Adelekun, T A; Ekwere, T R; Akinsola, A

    1999-01-01

    All cases of acute renal failure (ARF) seen over a two year (1993-94) period were evaluated. Those that had acute toxic nephropathy were further studied to determine the aetiologic agents involved, the clinical features and the effect of available treatment on its prognosis. Ten cases (33.3%) out of 30 ARF had toxins responsible for their renal failure. They were 8 males and 2 females. Agents responsible were green water in 2, naphthalene containing remedies in 2 and analgesic combination in 1 while herbal remedies were implicated in 5 cases. Anuria was a prominent feature occurring in 9 (90%) of the patients. The patients were uraemic with a mean serum creatinine of 1460 +/- 485.0 umol/1 and urea of 33.1 +/- 5.3 mmol/1 on admission. They were all anaemic with packed cell volume less than 18% in eight of the patients. Six (60%) of the patients required haemodialysis while 4 were managed conservatively. Prognosis was good as 8 (80%) of the patients survived and were followed up in the clinic for periods anging 6 to 18 months and their serum creatinine and urea levels normalised. It is concluded that acute toxic nephropathy is common in our practice, and it is eminently preventable. The prognosis is good if dialytic therapy is available.

  11. Acute oral toxicities of wildland fire control chemicals to birds.

    PubMed

    Vyas, Nimish B; Spann, James W; Hill, Elwood F

    2009-03-01

    Wildland fire control chemicals are released into the environment by aerial and ground applications to manage rangeland, grassland, and forest fires. Acute oral 24h median lethal dosages (LD50) for three fire retardants (Fire-Trol GTS-R, Phos-Chek D-75F, and Fire-Trol LCG-R) and two Class A fire suppressant foams (Silv-Ex and Phos-Chek WD881) were estimated for northern bobwhites, Colinus virginianus, American kestrels, Falco sparverius, and red-winged blackbirds, Agelaius phoeniceus. The LD50s of all chemicals for the bobwhites and red-winged blackbirds and for kestrels dosed with Phos-Chek WD881 and Silv-Ex were above the predetermined 2000mg chemical/kg body mass regulatory limit criteria for acute oral toxicity. The LD50s were not quantifiable for kestrels dosed with Fire-Trol GTS-R, Phos-Chek D-75F, and Fire-Trol LCG-R because of the number of birds which regurgitated the dosage. These chemicals appear to be of comparatively low order of acute oral toxicity to the avian species tested.

  12. Data on acute toxicity of the progestin STS 557.

    PubMed

    Hillesheim, H G; Hoffmann, H

    1983-02-01

    In mice and rabbits of both sexes the acute toxicity of STS 557 (17 alpha-cyanomethyl-17 beta-hydroxy-estra-4, 9-dien-3-one) was determined after its oral or parenteral (i.p., s.c.) administration. In rabbits increasing lethality was observed following STS 557 suspended in tylose solution at the dose range of 1.0 to 3.0 g/kg p.o. or i.p. The approximate LD50-values were 1.0 to 1.5 g/kg for the i.p. route and 1.0 to 2.0 g/kg for the oral route. Levonorgestrel injected i.p. did not cause any lethality up to the dose of 3.0 g/kg. After oral or s.c. administration to mice, doses of 4.0 g/kg STS 557 were well tolerated. A dose-related toxicity occurred only after i.p. doses between 0.5 and 1.0 g/kg (STS 557), and between 2.0 and 4.0 g/kg (levonorgestrel), respectively. Using an oily vehicle for the oral route in mice, the lethal threshold dose for STS 557 was lowered to about 2.0 g/kg. In conclusion, a low oral acute toxicity was determined for STS 557 corresponding to that of other progestagens like levonorgestrel or norethisterone.

  13. Identifying and designing chemicals with minimal acute aquatic toxicity.

    PubMed

    Kostal, Jakub; Voutchkova-Kostal, Adelina; Anastas, Paul T; Zimmerman, Julie Beth

    2015-05-19

    Industrial ecology has revolutionized our understanding of material stocks and flows in our economy and society. For this important discipline to have even deeper impact, we must understand the inherent nature of these materials in terms of human health and the environment. This paper focuses on methods to design synthetic chemicals to reduce their intrinsic ability to cause adverse consequence to the biosphere. Advances in the fields of computational chemistry and molecular toxicology in recent decades allow the development of predictive models that inform the design of molecules with reduced potential to be toxic to humans or the environment. The approach presented herein builds on the important work in quantitative structure-activity relationships by linking toxicological and chemical mechanistic insights to the identification of critical physical-chemical properties needed to be modified. This in silico approach yields design guidelines using boundary values for physiochemical properties. Acute aquatic toxicity serves as a model endpoint in this study. Defining value ranges for properties related to bioavailability and reactivity eliminates 99% of the chemicals in the highest concern for acute aquatic toxicity category. This approach and its future implementations are expected to yield very powerful tools for life cycle assessment practitioners and molecular designers that allow rapid assessment of multiple environmental and human health endpoints and inform modifications to minimize hazard.

  14. Acute toxicities of six manufactured nanomaterial suspensions to Daphnia magna

    NASA Astrophysics Data System (ADS)

    Zhu, Xiaoshan; Zhu, Lin; Chen, Yongsheng; Tian, Shengyan

    2009-01-01

    The rapid growth of nanotechnology is stimulating research on the potential environmental impacts of manufactured nanomaterials (MNMs). This paper summarizes a comprehensive study on the 48-h acute toxicity of water suspensions of six MNMs (i.e., ZnO, TiO2, Al2O3, C60, SWCNTs, and MWCNTs) to Daphnia magna, using immobilization and mortality as toxicological endpoints. The results show that the acute toxicities of all MNMs tested are dose dependent. The EC50 values for immobilization ranged from 0.622 mg/L (ZnO NPs) to 114.357 mg/L (Al2O3 NPs), while the LC50 values for mortality ranged from 1.511 mg/L (ZnO NPs) to 162.392 mg/L (Al2O3 NPs). In these tests, TiO2, Al2O3, and carbon-based nanomaterials were more toxic than their bulk counterparts. Moreover, D. magna were found to ingest nanomaterials from the test solutions through feeding behaviors, which indicates that the potential ecotoxicities and environmental health effects of these MNMs cannot be neglected.

  15. Antioxidant Capacity, Cytotoxicity, and Acute Oral Toxicity of Gynura bicolor.

    PubMed

    Teoh, Wuen Yew; Sim, Kae Shin; Moses Richardson, Jaime Stella; Abdul Wahab, Norhanom; Hoe, See Ziau

    2013-01-01

    Gynura bicolor (Compositae) which is widely used by the locals as natural remedies in folk medicine has limited scientific studies to ensure its efficacy and nontoxicity. The current study reports the total phenolic content, antioxidant capacity, cytotoxicity, and acute oral toxicity of crude methanol and its fractionated extracts (hexane, ethyl acetate, and water) of G. bicolor leaves. Five human colon cancer cell lines (HT-29, HCT-15, SW480, Caco-2, and HCT 116), one human breast adenocarcinoma cell line (MCF7), and one human normal colon cell line (CCD-18Co) were used to evaluate the cytotoxicity of G. bicolor. The present findings had clearly demonstrated that ethyl acetate extract of G. bicolor with the highest total phenolic content among the extracts showed the strongest antioxidant activity (DPPH radical scavenging assay and metal chelating assay), possessed cytotoxicity, and induced apoptotic and necrotic cell death, especially towards the HCT 116 and HCT-15 colon cancer cells. The acute oral toxicity study indicated that methanol extract of G. bicolor has negligible level of toxicity when administered orally and has been regarded as safe in experimental rats. The findings of the current study clearly established the chemoprevention potential of G. bicolor and thus provide scientific validation on the therapeutic claims of G. bicolor.

  16. DETERMINANTS OF VARIABILITY IN ACUTE TO CHRONIC TOXICITY RATIOS IN AQUATIC INVERTEBRATES AND FISH

    EPA Science Inventory

    Variability in acute to chronic ratios (ACRs; LC50/chronic value) has been a continuing interest in aquatic toxicology because of the reliance on ACRs to estimate chronic toxicity for chemicals and species with known acute toxicity but limited or no information on sublethal toxic...

  17. Acute Toxicity Estimation and Operational Risk Management of Chemical Warfare Agent Exposures

    DTIC Science & Technology

    2004-05-01

    December 2001 Deputy Assistant to The Secretary of Defense Chemical and Biological (Warfare Agent) Defense ((DATSD- CBD ) interim-certified acute...avoidance (detection), protection, decontamination, and medical intervention. d. Compares the DATSD- CBD interim-certified acute toxicity values...defense. 2. CONCLUSIONS AND RECOMMENDATIONS. a. Translating Toxicity Information into ORM Terminology. The 2001 DATSD- CBD toxicity

  18. Acute oral and percutaneous toxicity of pesticides to mallards: Correlations with mammalian toxicity data

    USGS Publications Warehouse

    Hudson, R.H.; Haegele, M.A.; Tucker, R.K.

    1979-01-01

    Acute oral (po) and 24-hr percutaneous (perc) LD50 values for 21 common pesticides (19 anticholinesterases, of which 18 were organophosphates, and one was a carbamate; one was an organochlorine central nervous system stimulant; and one was an organonitrogen pneumotoxicant) were determined in mallards (Anas platyrhynchos). Three of the pesticides tested were more toxic percutaneously than orally. An index to the percutaneous hazard of a pesticide, the dermal toxicity index (DTI = po LD50/perc LD50 ? 100), was also calculated for each pesticide. These toxicity values in mallards were compared with toxicity data for rats from the literature. Significant positive correlations were found between log po and log percutaneous LD50 values in mallards (r = 0.65, p 0.10). Variations in percutaneous methodologies are discussed with reference to interspecies variation in toxicity values. It is recommended that a mammalian DTI value approaching 30 be used as a guideline for the initiation of percutaneous toxicity studies in birds, when the po LD50 and/or projected percutaneous LD50 are less than expected field exposure levels.

  19. Assessing acute toxicities of pre- and post-treatment industrial wastewaters with Hydra attenuata: A comparative study of acute toxicity with the fathead minnow, Pimephales promelas

    SciTech Connect

    Fu, L.J.; Staples, R.E.; Stahl, R.G. Jr. . Haskell Lab. for Toxicology and Industrial Medicine)

    1994-04-01

    This study was undertaken to (a) determine wastewater treatment effectiveness using two freshwater organisms, (b) compare acute toxicity results from the two species exposed to the wastewaters, and (c) link acute and potential developmental toxicity of wastewaters in one organism. The acute toxicities of several pretreatment and post-treatment industrial waste-water samples wee evaluated with adult Hydra attenuata and fathead minnows. The acute LC50s agreed closely when results in Hydra attenuata were compared with those from fathead minnow tests. Acute LC50s ranged from 3 to >100% of samples with hydra, and from 1.0 to >100% of sample with fathead minnows. The results provided strong evidence of treatment effectiveness because toxicity decreased with progressive stages of treatment. Previously the Hydra Developmental Toxicity Assay was used as a prescreen mainly for in vitro assessment of developmental toxicity with pure compounds and to prioritized toxicants according to selective toxicity to the developing embryo. Recently the authors modified the assay for testing natural waters and wastewaters; hence, some of the wastewater samples also were tested for their developmental toxicity. In this case, the relative selective toxicity of these wastewater samples ranged from 0.7 to 2.1, indicating that no sample was uniquely toxic to the developing embryo, although acute toxicity was manifested. Overall, their results indicate the Hydra Assay functions appropriately in assessments of acute and developmental toxicity of industrial wastewaters and may be a simple and useful tool in a battery of tests for broader scale detection of environmental hazards.

  20. Non-animal Replacements for Acute Toxicity Testing.

    PubMed

    Barker-Treasure, Carol; Coll, Kevin; Belot, Nathalie; Longmore, Chris; Bygrave, Karl; Avey, Suzanne; Clothier, Richard

    2015-07-01

    Current approaches to predicting adverse effects in humans from acute toxic exposure to cosmetic ingredients still heavily necessitate the use of animals under EU legislation, particularly in the context of the REACH system, when cosmetic ingredients are also destined for use in other industries. These include the LD50 test, the Up-and-Down Procedure and the Fixed Dose Procedure, which are regarded as having notable scientific deficiencies and low transferability to humans. By expanding on previous in vitro tests, such as the animal cell-based 3T3 Neutral Red Uptake (NRU) assay, this project aims to develop a truly animal-free predictive test for the acute toxicity of cosmetic ingredients in humans, by using human-derived cells and a prediction model that does not rely on animal data. The project, funded by Innovate UK, will incorporate the NRU assay with human dermal fibroblasts in animal product-free culture, to generate an in vitro protocol that can be validated as an accepted replacement for the currently available in vivo tests. To date, the project has successfully completed an assessment of the robustness and reproducibility of the method, by using sodium lauryl sulphate (SLS) as a positive control, and displaying analogous results to those of the original studies with mouse 3T3 cells. Currently, the testing of five known ingredients from key groups (a surfactant, a preservative, a fragrance, a colour and an emulsifier) is under way. The testing consists of initial range-finding runs followed by three valid runs of a main experiment with the appropriate concentration ranges, to generate IC50 values. Expanded blind trials of 20 ingredients will follow. Early results indicate that this human cell-based test holds the potential to replace aspects of in vivo animal acute toxicity testing, particularly with reference to cosmetic ingredients.

  1. Zinc isotopic fractionation in Phragmites australis in response to toxic levels of zinc

    PubMed Central

    Caldelas, Cristina; Dong, Shuofei; Araus, José Luis; Jakob Weiss, Dominik

    2011-01-01

    Stable isotope signatures of Zn have shown great promise in elucidating changes in uptake and translocation mechanisms of this metal in plants during environmental changes. Here this potential was tested by investigating the effect of high Zn concentrations on the isotopic fractionation patterns of Phragmites australis (Cav.) Trin. ex Steud. Plants were grown for 40 d in a nutritive solution containing 3.2 μM (sufficient) or 2 mM (toxic) Zn. The Zn isotopic composition of roots, rhizomes, shoots, and leaves was analysed. Stems and leaves were sampled at different heights to evaluate the effect of long-distance transport on Zn fractionation. During Zn sufficiency, roots, rhizomes, and shoots were isotopically heavy (δ66ZnJMC Lyon=0.2‰) while the youngest leaves were isotopically light (–0.5‰). During Zn excess, roots were still isotopically heavier (δ66Zn=0.5‰) and the rest of the plant was isotopically light (up to –0.5‰). The enrichment of heavy isotopes at the roots was attributed to Zn uptake mediated by transporter proteins under Zn-sufficient conditions and to chelation and compartmentation in Zn excess. The isotopically lighter Zn in shoots and leaves is consistent with long-distance root to shoot transport. The tolerance response of P. australis increased the range of Zn fractionation within the plant and with respect to the environment. PMID:21193582

  2. Acute renal toxicity after ingestion of Lava light liquid.

    PubMed

    Erickson, T B; Aks, S E; Zabaneh, R; Reid, R

    1996-06-01

    A 65-year-old man with a history of alcohol abuse and seizure disorder presented to the emergency department with altered mental status, increased anion gap acidosis, phenytoin toxicity, and acute kidney failure. The patient had ingested the liquid contents of a Lava light, which contained chlorinated paraffin, polyethylene glycol (molecular weight 200), kerosene, and micro-crystalline wax. Gas chromatography-mass spectrophotometry of the patient's blood produced results consistent with the same analysis of the Lava light contents. After 3 days of declining mental status and worsening kidney function, the patient required hemodialysis. After a prolonged hospitalization, the patient was discharged home with residual renal insufficiency. Although multifactorial, the associated renal toxicity was most probably related to the low molecular weight polyethylene glycol content of the lamp's liquid contents.

  3. Acute renal insufficiency and toxic hepatitis following scorpions sting.

    PubMed

    Krkic-Dautovic, Sajma; Begovic, Begler

    2007-01-01

    Scorpion sting is a huge medical problem in countries of South America, Arabian Peninsula and Africa. In countries of Mediterranean region, where Bosnia and Herzegovina belongs, this problem is sporadic. Following the sting of very poisonous red scorpions, death may occur inside of 48 hours by reason of cardiac arrest and acute renal insufficiency (ARI). In our work we represent a case of 54-years old man. In his case, ARI and toxic hepatitis developed inside of 24 hours after the scorpion sting. Applied conservative therapy was not sufficient enough to solve ARI, so patient needed haemodialysis. With intensive conservative therapy and haemodialysis applied every other day, ARI and toxic hepatitis were solved within 25 days. After that, patient was released from hospital for ambulant treatment.

  4. Quinolone arthropathy--acute toxicity to immature articular cartilage.

    PubMed

    Gough, A W; Kasali, O B; Sigler, R E; Baragi, V

    1992-01-01

    A class effect of quinolone antibacterial agents observed during animal toxicity testing is a specific arthropathy (QAP). Despite the growing list of laboratory animals susceptible to QAP and reports of arthralgia in patients treated with quinolones, the potential for QAP development in humans remains unknown. This review discusses current concepts in the biology of articular cartilage and how these concepts elucidate QAP pathogenesis. Biomechanical forces within synovial joints and toxicokinetic properties of quinolones contribute to QAP induction. Since a limited number of mechanistic pathways exist for acute articular damage, QAP may serve as a research tool to probe the pathobiology of injury to articular cartilage.

  5. Salinity-dependent toxicities of zinc oxide nanoparticles to the marine diatom Thalassiosira pseudonana.

    PubMed

    Yung, Mana M N; Wong, Stella W Y; Kwok, Kevin W H; Liu, F Z; Leung, Y H; Chan, W T; Li, X Y; Djurišić, A B; Leung, Kenneth M Y

    2015-08-01

    This study comprehensively investigated the influences of salinity, exposure concentration and time on the aggregate size, surface charge and dissolution of zinc oxide nanoparticles (ZnO-NPs; 20nm) in seawater, and examined the interacting effect of salinity and waterborne exposure of ZnO-NPs on the marine diatom Thalassiosira pseudonana for 96h. We found that aggregate sizes of ZnO-NPs significantly increased with increasing salinity, but generally decreased with increasing exposure concentration. Ion release decreased with increasing salinity, whereas the surface charge of the particles was not affected by salinity. The increased aggregate size and decreased ion release with increasing salinity, and consequently lower concentration of bioavailable zinc ions, resulted in decreased toxicity of ZnO-NPs at higher salinity in general in terms of growth inhibition (IC50) and chlorophyll fluorescence (EC50 - ФPo and EC50 - Ф2). However, IC50s and EC50s of ZnO-NPs were smaller than those of Zn(2+) (from ZnO-NPs ultrafiltrate and ZnCl2), indicating that dissolved Zn(2+) can only partially explain the toxicity of ZnO-NPs. SEM images showed that ZnO-NPs attached on the diatom frustule surface, suggesting that the interaction between the nanoparticles and the cell surface may acerbate the toxicity of ZnO-NPs. Our results linked the physicochemical characteristics of ZnO-NPs in seawater with their toxicities to the marine diatom and highlighted the importance of salinity as an influential environmental factor governing the aggregation, dissolution and the toxicity of ZnO-NPs.

  6. Characterization of the dinophysistoxin-2 acute oral toxicity in mice to define the Toxicity Equivalency Factor.

    PubMed

    Abal, Paula; Louzao, M Carmen; Cifuentes, José Manuel; Vilariño, Natalia; Rodriguez, Ines; Alfonso, Amparo; Vieytes, Mercedes R; Botana, Luis M

    2017-04-01

    Ingestion of shellfish with dinophysistoxin-2 (DTX2) can lead to diarrheic shellfish poisoning (DSP). The official control method of DSP toxins in seafood is the liquid chromatography-mass spectrometry analysis (LC-MS). However in order to calculate the total toxicity of shellfish, the concentration of each compound must be multiplied by individual Toxicity Equivalency Factor (TEF). Considering that TEFs caused some controversy and the scarce information about DTX2 toxicity, the aim of this study was to characterize the oral toxicity of DTX2 in mice. A 4-Level Up and Down Procedure allowed the characterization of DTX2 effects and the estimation of DTX2 oral TEF based on determination of the lethal dose 50 (LD50). DTX2 passed the gastrointestinal barrier and was detected in urine and feces. Acute toxicity symptoms include diarrhea and motionless, however anatomopathology study and ultrastructural images restricted the toxin effects to the gastrointestinal tract. Nevertheless enterocytes microvilli and tight junctions were not altered, disconnecting DTX2 diarrheic effects from paracellular epithelial permeability. This is the first report of DTX2 oral LD50 (2262 μg/kg BW) indicating that its TEF is about 0.4. This result suggests reevaluation of the present TEFs for the DSP toxins to better determine the actual risk to seafood consumers.

  7. Acute dietary zinc deficiency before conception compromises oocyte epigenetic programming and disrupts embryonic development

    PubMed Central

    Tian, X; Diaz, FJ

    2013-01-01

    Recent findings show that zinc is an important factor necessary for regulating the meiotic cell cycle and ovulation. However, the role of zinc in promoting oocyte quality and developmental potential is not known. Using an in vivo model of acute dietary zinc deficiency, we show that feeding a zinc deficient diet (ZDD) for 3–5 days before ovulation (preconception) dramatically disrupts oocyte chromatin methylation and preimplantation development. There was a dramatic decrease in histone H3K4 trimethylation and global DNA methylation in zinc deficient oocytes. Moreover, there was a 3–20 fold increase in transcript abundance of repetitive elements (Iap, Line1, Sineb1, Sineb2), but a decrease in Gdf9, Zp3 and Figla mRNA. Only 53% and 8% of mature eggs reached the 2-cell stage after IVF in animals receiving a 3 and 5 day ZDD, respectively, while a 5 day ZDD in vivo reduced the proportion of 2-cells to 49%. In vivo fertilized 2-cell embryos cultured in vitro formed fewer (38%) blastocysts compared to control embryos (74%). Likewise, fewer blastocyst and expanded blastocyst were collected from the reproductive tract of zinc deficient animals on day 3.5 of pregnancy. This could be due to a decrease in Igf2 and H19 mRNA in ZDD blastocyst. Supplementation with a methyl donor (SAM) during IVM restored histone H3K4me3 and doubled the IVF success rate from 17% to 43% in oocytes from zinc deficient animals. Thus, the terminal period of oocyte development is extremely sensitive to perturbation in dietary zinc availability. PMID:23348678

  8. INTER-SPECIES MODELS FOR ACUTE AQUATIC TOXICITY BASED ON MECHANISM OF ACTION

    EPA Science Inventory

    This presentation will provide interspecies QSARs for acute toxicity to 17 aquatic species, such as fish, snail, tadpole, hydrozoan, crustacean, insect larvae, and bacteria developed using 5,000 toxic effect results for approximately 2400 chemicals.

  9. Predicting fish acute toxicity using a fish gill cell line-based toxicity assay.

    PubMed

    Tanneberger, Katrin; Knöbel, Melanie; Busser, Frans J M; Sinnige, Theo L; Hermens, Joop L M; Schirmer, Kristin

    2013-01-15

    The OECD test guideline 203 for determination of fish acute toxicity requires substantial numbers of fish and uses death as an apical end point. One potential alternative are fish cell lines; however, several studies indicated that these appear up to several orders of magnitude less sensitive than fish. We developed a fish gill cell line-based (RTgill-W1) assay, using several measures to improve sensitivity. The optimized assay was applied to determine the toxicity of 35 organic chemicals, having a wide range of toxicity to fish, mode of action and physicochemical properties. We found a very good agreement between in vivo and in vitro effective concentrations. For up to 73% of the tested compounds, the difference between the two approaches was less than 5-fold, covering baseline toxicants but as well compounds with presumed specific modes of action, including reactivity, inhibition of acetylcholine esterase or uncoupling of oxidative phosphorylation. Accounting for measured chemical concentrations eliminated two outliers, the hydrophobic 4-decylaniline and the volatile 2,3-dimethyl-1,3-butadiene, with an outlier being operationally defined as a substance showing a more than 10-fold difference between in vivo/in vitro effect concentrations. Few outliers remained. The most striking were allyl alcohol (2700-fold), which likely needs to be metabolically activated, and permethrin (190-fold) and lindane (63-fold), compounds acting, respectively, on sodium and chloride channels in the brain of fish. We discuss further developments of this assay and suggest its use beyond predicting acute toxicity to fish, for example, as part of adverse outcome pathways to replace, reduce, or refine chronic fish tests.

  10. [Acute Toxicity of Coptis chinensis Rhizome Extracts to Daphnia carinata].

    PubMed

    Chen, Ya-nan; Yuan, Ling

    2015-10-01

    Coptis chinensis rhizome and preparations were widely used for the treatment of fish diseases in aquaculture. the acute toxicological effect of CRE on lethal, movement and phototaxis was studied on Daphnia carinata monoclone as a test animal in the present experiment. The results showed that CRE was acute toxic to this animal and alkaloids berberine concentrations in CRE changed in the following sequence: half lethal > half inhibitory > limitable, which led to a significant change in phototaxis index of Daphnia carinata. The concentration of CRE for the significant change in phototaxis index was 4.27 mg x L(-1), which was lower than the concentration in water to cure the fish diseases and this conclusion indicated an ecological risk of this antibiotic to Daphnia carinata in aquaculture. In addition, the concentration of CRE in phototaxis index was changed from 30.62 times at 48th hour to 36.51 times at 24th hour that were lower than half lethal concentration. Detecting phototaxis index was easy and only 3 hours was required, so utilizing the quickly change of Daphnia carinata phototaxis can be an effective method to monitor the toxicity effect of CRE on Daphnia carinata. The abuse of rhizome or preparations in aquaculture might destroy the aquatic food chain, resulting in an imbalance of aquatic ecosystems.

  11. Combined toxicity of copper, cadmium, zinc, lead, nickel, and chrome to the copepod Tisbe holothuriae

    SciTech Connect

    Verriopoulos, G.; Dimas, S.

    1988-09-01

    In recent years much work has been concerned with the determination of various contaminants in the environment and with the establishment of the toxicity of these compounds to marine animals. Heavy metals are of increasing concern as pollutants of marine and especially coastal environments. Mixtures of heavy metals may produce unexpected effects. The purpose of this study was to determine the acute toxicity of six heavy metals (Cu, Cd, Zn, Pb, Ni and Cr) to the marine copepod Tisbe holothuriae Humes and to see whether there is any interaction between these metals, when applied jointly.

  12. Acute oral toxicity of the herbicide BUREX EKO in pheasants.

    PubMed

    Legáth, J; Mlynarcíková, H; Svický, E; Lenhardt, L; Kacmár, P; Benová, K; Kovác, G

    1996-12-01

    The aim of this study was to determine the acute LD50, clinical symptoms and pathological changes of acute BUREX EKO intoxication in pheasants according to OECD No 205. Medium lethal dose (LD50) of BUREX EKO in pheasant is 3.84 ml/kg body weight with the upper level of reliability 4.50 ml and lower level of reliability 3.27 ml/kg body weight. As far as the calculation to the effective substance is concerned it is 1077 mg of chloridazone per kg body weight with the interval of reliability from 919 to 1263 mg/kg body weight. Calculated the effective substance of chloridazone (3.84 ml is LD50 of BUREX EKO which contains 1077 mg of chloridazone) BUREX EKO can be classified as the moderately toxic substance to pheasants. There were following clinical symptoms of the BUREX EKO intoxication in pheasants: apathy, drowsiness, incapability to move, ruffled feathers, slight diarrhoea, strenuous respiration, tonico-clonical cramps before death, decease with the head expressively bent rearwards. There was a relatively fast beginning of rigor mortis in dead pheasants. Pathologico-anatomical dissection of the pheasants obtained under conditions of acute intoxication did not reveal any changes on the organs of both experimental and control pheasants which would be immediately connected with the effect of the administered substance. Hyperaemia was recorded by histologico-pathological investigation of the liver and kidneys. No changes on the brain and intestine wall were recorded.

  13. Influence of water quality parameters on acute silver toxicity

    SciTech Connect

    Bills, T.; Forsythe, B. II; Wenholz, M.; Jeffers, R.; Waldrop, V.; La Point, T.; Bens, C.; Cobb, G.; Klaine, S.J.

    1995-12-31

    The data to adequately characterize the influence of water quality on silver toxicity in freshwater are lacking or poorly developed. Current attempts to extrapolate existing data sets to many sites result in extremely low silver limits. The error associated with these extrapolations dictate that a silver toxicity data set, accounting for various water quality parameters, be generated. The interactive effects of chloride, hardness, alkalinity, total organic carbon, and pH on the acute toxicity of silver (AgNO{sub 3}) were measured using juvenile fathead minnows (Pimephales promelas) and Daphnia magna. The 96-hr LC50 for fathead minnows at the lowest tested levels of water quality parameters was 1.4 ug/L. At the highest levels tested, the 96-hr LC50 for fathead minnows was 3.8 ug/L. Preliminary results suggest the 48-hr LC50 values for Daphnia magna were similar to those of the fish. These results indicate a mitigating effect of certain water quality parameters.

  14. Acetone potentiation of acute acetonitrile toxicity in rats

    SciTech Connect

    Freeman, J.J.; Hayes, E.P.

    1985-01-01

    The purpose of these studies was to investigate the nature and mechanism of a toxicologic interaction between acetonitrile and acetone. Results of oral doe-response studies utilizing 1:1 (w/w) mixture of acetonitrile and acetone, or varying doses of acetonitrile administered together with a constant dose of acetone, indicated that acetone potentiated acute acetonitrile toxicity three- to fourfold in rats. The onset of severe toxicity (manifested by tremors and convulsions) was delayed in the groups dosed with both solvents compared to the groups that received acetonitrile or acetone alone. Blood cyanide (a metabolite of acetonitrile) and serum acetonitrile and acetone concentrations were measured after oral administration of 25% aqueous solutions of acetonitrile, acetone, or acetonitrile plus acetone. Concentrations of cyanide in the blood of rats given acetonitrile plus acetone remained near baseline, in contrast to the high concentrations found in rats dosed with acetonitrile alone. At 34-36 h, high blood cyanide concentrations were found in rats dosed with both of the solvents. This delayed onset of elevation of blood cyanide coincided with the occurrence of clinical signs and with the disappearance of serum acetone. In further pharmacokinetic studies, blood cyanide concentrations were measured after similar dosage regimens of acetone and acetonitrile. Peak cyanide concentrations were found to be significantly greater in rats dosed with both solvents than in rats given only acetonitrile. Administration of either sodium thiosulfate or a second dose of acetone prevented the toxicity associated with exposure to both solvents.

  15. Zinc rescues dopaminergic SK-N-SH cell lines from methamphetamine-induced toxicity.

    PubMed

    Ajjimaporn, Amornpan; Shavali, Shaik; Ebadi, Manuchair; Govitrapong, Piyarat

    2008-12-16

    Methamphetamine (METH) is a potent inducer of dopamine (DA) release, and is toxic to DA neurons. It has been reported that the formation of free radicals is an early signaling event that mediates cell death caused by METH. Currently, studies suggest that the generation of free radicals by oxidative catabolism of DA and dysfunction of the mitochondrial respiration chain are important mediators of neuronal death in Parkinson's disease (PD) and one process may counter the effect of the other. In our previous study, we investigated the deleterious effects of METH-induced reactive oxygen species (ROS) and mitochondrial dysfunction in dopaminergic SK-N-SH cells in culture, and assessed whether zinc-metallothionein induction provided mitochondrial protection against METH-induced mitochondrial dysfunction. Our present data demonstrate that METH enhances lipid peroxidation and mitochondrial manganese superoxide dismutase (MnSOD) enzyme levels, and decreases the antioxidant-reduced glutathione (GSH) together with an inhibition of mitochondrial complex-I activity. Pre-treatment with zinc markedly prevents the increase of lipid peroxidation and provides mitochondrial protection by scavenging free radicals via metallothionein and by increasing mitochondrial GSH and complex-I levels, thus rescuing SK-N-SH cells from METH toxicity. It should be emphasized that, however, it is still not clear that effects of METH on cultured SK-N-SH reliably model the effects of METH in the intact animal. Further studies in the intact animal are needed.

  16. A novel approach reveals that zinc oxide nanoparticles are bioavailable and toxic after dietary exposures

    USGS Publications Warehouse

    Croteau, M.-N.; Dybowska, A.D.; Luoma, S.N.; Valsami-Jones, E.

    2011-01-01

    If engineered nanomaterials are released into the environment, some are likely to end up associated with the food of animals due to aggregation and sorption processes. However, few studies have considered dietary exposure of nanomaterials. Here we show that zinc (Zn) from isotopically modified 67ZnO particles is efficiently assimilated by freshwater snails when ingested with food. The 67Zn from nano-sized 67ZnO appears as bioavailable as 67Zn internalized by diatoms. Apparent agglomeration of the zinc oxide (ZnO) particles did not reduce bioavailability, nor preclude toxicity. In the diet, ZnO nanoparticles damage digestion: snails ate less, defecated less and inefficiently processed the ingested food when exposed to high concentrations of ZnO. It was not clear whether the toxicity was due to the high Zn dose achieved with nanoparticles or to the ZnO nanoparticles themselves. Further study of exposure from nanoparticles in food would greatly benefit assessment of ecological and human health risks. ?? 2011 Informa UK, Ltd.

  17. Zinc

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zinc was recognized as an essential trace metal for humans during the studies of Iranian adolescent dwarfs in the early 1960s. Zinc metal existing as Zn2+ is a strong electron acceptor in biological systems without risks of oxidant damage to cells. Zn2+ functions in the structure of proteins and is ...

  18. A combined toxicity study of zinc oxide nanoparticles and vitamin C in food additives

    NASA Astrophysics Data System (ADS)

    Wang, Yanli; Yuan, Lulu; Yao, Chenjie; Ding, Lin; Li, Chenchen; Fang, Jie; Sui, Keke; Liu, Yuanfang; Wu, Minghong

    2014-11-01

    At present, safety evaluation standards for nanofood additives are made based on the toxic effects of a single additive. Since the size, surface properties and chemical nature influence the toxicity of nanomaterials, the toxicity may have dramatically changed when nanomaterials are used as food additives in a complex system. Herein, we investigated the combined toxicity of zinc oxide nanoparticles (ZnO NPs) and vitamin C (Vc, ascorbic acid). The results showed that Vc increased the cytotoxicity significantly compared with that of the ZnO only NPs. When the cells were exposed to ZnO NPs at a concentration less than 15 mg L-1, or to Vc at a concentration less than 300 mg L-1, there was no significant cytotoxicity, both in the case of gastric epithelial cell line (GES-1) and neural stem cells (NSCs). However, when 15 mg L-1 of ZnO NPs and 300 mg L-1 of Vc were introduced to cells together, the cell viability decreased sharply indicating significant cytotoxicity. Moreover, the significant increase in toxicity was also shown in the in vivo experiments. The dose of the ZnO NPs and Vc used in the in vivo study was calculated according to the state of food and nutrition enhancer standard. After repeated oral exposure to ZnO NPs plus Vc, the injury of the liver and kidneys in mice has been indicated by the change of these indices. These findings demonstrate that the synergistic toxicity presented in a complex system is essential for the toxicological evaluation and safety assessment of nanofood.At present, safety evaluation standards for nanofood additives are made based on the toxic effects of a single additive. Since the size, surface properties and chemical nature influence the toxicity of nanomaterials, the toxicity may have dramatically changed when nanomaterials are used as food additives in a complex system. Herein, we investigated the combined toxicity of zinc oxide nanoparticles (ZnO NPs) and vitamin C (Vc, ascorbic acid). The results showed that Vc increased the

  19. Neutral red uptake cytotoxicity tests for estimating starting doses for acute oral toxicity tests.

    PubMed

    Stokes, William S; Casati, Silvia; Strickland, Judy; Paris, Michael

    2008-05-01

    In vitro cytotoxicity assays can be used as alternative toxicity tests to reduce the total number of animals needed for acute oral toxicity tests. This unit describes two methods for determining the in vitro cytotoxicity of test substances using neutral red uptake (NRU) and using the in vitro data to determine starting doses for in vivo acute oral systemic toxicity tests, e.g., the up-and-down procedure or the acute toxic class method. The use of the NRU methods to determine starting doses for acute oral toxicity tests may reduce the number of animals required, and for relatively toxic substances, this approach may also reduce the number of animals that die or require humane euthanasia due to severe toxicity. An interlaboratory validation study has demonstrated that the methods are useful and reproducible for these purposes. Two standardized protocols provide details for performing NRU tests with rodent and human cells.

  20. A combined toxicity study of zinc oxide nanoparticles and vitamin C in food additives.

    PubMed

    Wang, Yanli; Yuan, Lulu; Yao, Chenjie; Ding, Lin; Li, Chenchen; Fang, Jie; Sui, Keke; Liu, Yuanfang; Wu, Minghong

    2014-12-21

    At present, safety evaluation standards for nanofood additives are made based on the toxic effects of a single additive. Since the size, surface properties and chemical nature influence the toxicity of nanomaterials, the toxicity may have dramatically changed when nanomaterials are used as food additives in a complex system. Herein, we investigated the combined toxicity of zinc oxide nanoparticles (ZnO NPs) and vitamin C (Vc, ascorbic acid). The results showed that Vc increased the cytotoxicity significantly compared with that of the ZnO only NPs. When the cells were exposed to ZnO NPs at a concentration less than 15 mg L(-1), or to Vc at a concentration less than 300 mg L(-1), there was no significant cytotoxicity, both in the case of gastric epithelial cell line (GES-1) and neural stem cells (NSCs). However, when 15 mg L(-1) of ZnO NPs and 300 mg L(-1) of Vc were introduced to cells together, the cell viability decreased sharply indicating significant cytotoxicity. Moreover, the significant increase in toxicity was also shown in the in vivo experiments. The dose of the ZnO NPs and Vc used in the in vivo study was calculated according to the state of food and nutrition enhancer standard. After repeated oral exposure to ZnO NPs plus Vc, the injury of the liver and kidneys in mice has been indicated by the change of these indices. These findings demonstrate that the synergistic toxicity presented in a complex system is essential for the toxicological evaluation and safety assessment of nanofood.

  1. Evaluation of acute and sub-acute toxicity of Pinus eldarica bark extract in Wistar rats

    PubMed Central

    Ghadirkhomi, Akram; Safaeian, Leila; Zolfaghari, Behzad; Agha Ghazvini, Mohammad Reza; Rezaei, Parisa

    2016-01-01

    Objective: Pinus eldarica (P. eldarica) is one of the most common pines in Iran which has various bioactive constituents and different uses in traditional medicine. Since there is no documented evidence for P. eldarica safety, the acute and sub-acute oral toxicities of hydroalcoholic extract of P. eldarica bark were investigated in male and female Wistar rats in this study. Materials and Methods: In the acute study, a single dose of extract (2000 mg/kg) was orally administered and animals were monitored for 7 days. In the sub-acute study, repeated doses (125, 250 and 500 mg/kg/day) of the extract were administered for 28 days and biochemical, hematological and histopathological parameters were evaluated. Results: Our results showed no sign of toxicity and no mortality after single or repeated administration of P. eldarica. The median lethal dose (LD50) of P. eldarica was determined to be higher than 2000 mg/kg. The mean body weight and most of the biochemical and hematological parameters showed normal levels. There were only significant decreases in serum triglyceride levels at the doses of 250 and 500 mg/kg of the extract in male rats (p<0.05 and p<0.01, respectively) and in monocyte counts at the highest dose of the extract in both male and female rats (p<0.05). Mild inflammation was also found in histological examination of kidney and liver tissues at the highest dose of extract. Conclusion: Oral administration of the hydroalcoholic extract of P. eldarica bark may be considered as relatively non-toxic particularly at the doses of 125 and 250 mg/kg. PMID:27761426

  2. Acute inhibition of iron bioavailability by zinc: studies in humans.

    PubMed

    Olivares, Manuel; Pizarro, Fernando; Ruz, Manuel; de Romaña, Daniel López

    2012-08-01

    Iron (Fe) and zinc (Zn) deficiencies constitute two of the most important nutritional and public health problems affecting developing countries. Combined supplementation or fortification with Zn and Fe are strategies that can be used to improve the Zn and Fe status of a population. However, there is concern about potential negative interactions between these two micronutrients due to a competitive binding to DMT1 and Zip14 transporter. Studies performed in humans have shown an inhibitory effect of Zn on Fe absorption when both minerals are given together as a solution in fasting conditions. We found that at low doses of iron (0.5 mg) the threshold for the inhibition of iron bioavailability was at a Zn:Fe wt/wt ratio ≥5.9:1, whereas at higher doses of Fe (10 mg) this inhibition occurred at 1:1 Zn:Fe wt/wt ratio. This differential response could be explained by the variation in the abundance of both cations as they compete for a limited number of shared transporters at the enterocyte. Conflicting results have been obtained when this interaction was studied in different food matrices. A negative interaction was not observed when Fe and Zn were provided in a composite hamburger meal, premature formula, human milk, or cow milk. A decrease on Fe absorption was observed in only 1 of 3 studies when Fe and Zn were supplied in wheat flour. The possibility of a negative interaction should be considered for supplementation or fortification programs with both microminerals.

  3. Combinatorial QSAR Modeling of Rat Acute Toxicity by Oral Exposure

    EPA Science Inventory

    Quantitative Structure-Activity Relationship (QSAR) toxicity models have become popular tools for identifying potential toxic compounds and prioritizing candidates for animal toxicity tests. However, few QSAR studies have successfully modeled large, diverse mammalian toxicity end...

  4. Toxicity of white phosphorus to waterfowl: acute exposure in mallards

    USGS Publications Warehouse

    Sparling, D.W.; Gustafson, M.; Klein, P.; Karouna-Renier, N.

    1997-01-01

    As part of an effort to understand extensive, white phosphorus (P4)-induced waterfowl mortality at Eagle River Flats, Fort Richardson, Alaska, we conducted a number of acute toxicity tests using penned mallards (Anas platyrhynchos) in 1993 and 1994. The 24-hr median lethal dose (LD50) for P4 dissolved in oil was 6.46 mg/kg in adult males and 6.96 mg/kg in adult females. Although the median lethal doses were not statistically different, the female dose-response curve had a statistically shallower slope than that of males. The LD50 for the ecologically more relevant pelletized form of P4 in adult males was 4.05 mg/kg. In mallards, one mechanism of P4 toxicity caused rapid (3 to 10 hr) mortality and had signs consistent with anoxia. A second, slower acting mechanism resulted in hepatic and renal pathology including extensive fat deposition in the liver and cellular necrosis. White phosphorus accumulated in adipose tissues, but only for a few days.

  5. Influence of chemical and environmental stressors on acute cadmium toxicity

    SciTech Connect

    Baer, K.N.; Benson, W.H.

    1987-01-01

    Previous investigations have demonstrated that the cytosolic protein metallothionein (MT) is induced not only by exposure to certain heavy metals but also by a variety of other factors, including environmental stress. While MT synthesis has been observed with exposure to cold temperatures, there is a paucity of data concerning the influence of cold on heavy-metal toxicity. The present investigation focused on the influence of metal and cold pretreatments on the acute toxicity of cadmium. Mortalities of 80% and 100% were observed for mice orally administered challenge doses of 100 mg Cd/kg and 150 mg Cd/kg, respectively. To determine a protective cadmium pretreatment dose, animals were administered 2.5, 5, 10, 20, 25, and 50 mg Cd/kg 24 h prior to cadmium challenge. In animals pretreated with 10 mg Cd/kg, mortalities of 20% and 70% were observed with the respective challenge doses. Immediately following cold stress (4/sup 0/C, 12 h), mortalities of 30% and 90% were observed with cadmium challenge doses of 100 and 150 mg Cd/kg, respectively. Significant correlations were demonstrated between induced hepatic MT concentrations and cadmium pretreatment, as well as cold pretreatment. The induced tolerance to cadmium was attributed, in part, to the induction of MT synthesis. Furthermore, the induced levels of MT resulting from cold stress may confound the simplistic approach of using MT as a biological monitor of occupational exposure to cadmium.

  6. Acute toxicity evaluation for quinolone antibiotics and their chlorination disinfection processes.

    PubMed

    Li, Min; Wei, Dongbin; Du, Yuguo

    2014-09-01

    Acute toxicity of 21 quinolone antibiotics was monitored using photobacterium Vibrio fischeri assay. The minimum IC20 (inhibitory concentration for 20% luminescence elimination) was obtained at the least 18.86μmol/L for the tested quinolones. A quantitative structure-activity relationship model was established to investigate the possible mechanism for the acute toxicity. The critical physicochemical descriptors, describing σ and π atom electronegativity, implied that the electron transfer might occur between the quinolones and photobacterium V. fischeri. Although the quinolones exhibited limited acute toxicity to photobacterium, toxicity elevation was detected after their chlorination. Hence, chlorination disinfection treatment of quinolone-containing water should be of concerns.

  7. Reduction of acute toxicity and genotoxicity of dye effluent using Fenton-coagulation process.

    PubMed

    Zhang, Jing; Chen, Shuo; Zhang, Ying; Quan, Xie; Zhao, Huimin; Zhang, Yaobin

    2014-06-15

    Dye wastewater exhibits significant ecotoxicity even though its physico-chemical parameters meet the discharge standards. In this work, the acute toxicity and genotoxicity of dye effluent were tested, and the Fenton-coagulation process was carried out to detoxify this dye effluent. The acute toxicity was evaluated according to the mortality rate of zebrafish, and genotoxicity was evaluated by micronucleus (MN) and comet assays. Removal of color and chemical oxygen demand (COD) was also investigated. The results indicated that the dye effluent showed strong acute toxicity and genotoxicity to zebrafish. After 4h of treatment by Fenton-coagulation process, the dye effluent exhibited no significant acute toxicity and genotoxicity to zebrafish. In addition, its COD was less than 50mg/L, which met the discharge standard. It demonstrates that Fenton-coagulation process can comprehensively reduce the acute toxicity and genotoxicity as well as the COD of the dye effluent.

  8. Acute Selenium Toxicity Associated With a Dietary Supplement

    PubMed Central

    MacFarquhar, Jennifer K.; Broussard, Danielle L.; Melstrom, Paul; Hutchinson, Richard; Wolkin, Amy; Martin, Colleen; Burk, Raymond F.; Dunn, John R.; Green, Alice L.; Hammond, Roberta; Schaffner, William; Jones, Timothy F.

    2011-01-01

    Background Selenium is an element necessary for normal cellular function, but it can have toxic effects at high doses. We investigated an outbreak of acute selenium poisoning. Methods A case was defined as the onset of symptoms of selenium toxicity in a person within 2 weeks after ingesting a dietary supplement manufactured by “Company A,” purchased after January 1, 2008. We conducted case finding, administered initial and 90-day follow-up questionnaires to affected persons, and obtained laboratory data where available. Results The source of the outbreak was identified as a liquid dietary supplement that contained 200 times the labeled concentration of selenium. Of 201 cases identified in 10 states, 1 person was hospitalized. The median estimated dose of selenium consumed was 41 749 μg/d (recommended dietary allowance is 55 μg/d). Frequently reported symptoms included diarrhea (78%), fatigue (75%), hair loss (72%), joint pain (70%), nail discoloration or brittleness (61%), and nausea (58%). Symptoms persisting 90 days or longer included fingernail discoloration and loss (52%), fatigue (35%), and hair loss (29%). The mean initial serum selenium concentration of 8 patients was 751 μg/L (reference range, ≤125 μg/L). The mean initial urine selenium concentration of 7 patients was 166 μg/24 h (reference range, ≤55 μg/24 h). Conclusions Toxic concentrations of selenium in a liquid dietary supplement resulted in a widespread outbreak. Had the manufacturers been held to standards used in the pharmaceutical industry, it may have been prevented. PMID:20142570

  9. Removal of toxic zinc from water/wastewater using eucalyptus seeds activated carbon: non-linear regression analysis.

    PubMed

    Senthil Kumar, Ponnusamy; Saravanan, Anbalagan; Anish Kumar, Kodyingil; Yashwanth, Ramesh; Visvesh, Sridharan

    2016-08-01

    In the present study, a novel activated carbon was prepared from low-cost eucalyptus seeds, which was utilised for the effectively removal of toxic zinc from the water/wastewater. The prepared adsorbent was studied by Fourier transform infrared spectroscopy and scanning electron microscopic characterisation studies. Adsorption process was experimentally performed for optimising the influencing factors such as adsorbent dosage, solution pH, contact time, initial zinc concentration, and temperature for the maximum removal of zinc from aqueous solution. Adsorption isotherm of zinc removal was ensued Freundlich model, and the kinetic model ensued pseudo-second order model. Langmuir monolayer adsorption capacity of the adsorbent for zinc removal was evaluated as 80.37 mg/g. The results of the thermodynamic studies suggested that the adsorption process was exothermic, thermodynamically feasible and impulsive process. Finally, a batch adsorber was planned to remove zinc from known volume and known concentration of wastewater using best obeyed model such as Freundlich. The experimental details showed the newly prepared material can be effectively utilised as a cheap material for the adsorption of toxic metal ions from the contaminated water.

  10. Isolation and characterization of acutely toxic fractions in oil sands wastewater

    SciTech Connect

    Verbeek, A.; Mackay, W.; MacKinnon, M.

    1995-12-31

    Extraction of oil from oil sand using the hot water flotation method results in the production of large volumes of wastewater that are acutely toxic to aquatic organisms. At Syncrude Canada Ltd. and Suncor Oil Sands Group Inc., this wastewater is stored in large tailings ponds that must eventually be reclaimed. The acute toxicity of these wastewaters was assessed and the acutely toxic fractions were identified. Samples were collected from the surface and fine tails zones of the Syncrude and Suncor tailings ponds during the summers of 1991 and 1992. The Microtox bioassay was used to assess the acute toxicity before and after various treatments. Where significant reductions in acute toxicity were found, further acute toxicity tests were carried out using Daphnia magna and rainbow trout. The Microtox IC{sub 50} of all centrifuged tailings pond water samples varied between 26.5 and 46%. Daphnia LC{sub 50}s varied between 76 and 98% and a rainbow trout LC{sub 50} was 12.5 %. Organic compounds that have a non-polar component, as removed by solid phase extraction with C{sub 18} sorbent, accounted for all the acute toxicity (100%) of all samples. Organic ``acids``, as removed by precipitation at pH 2.5, also accounted for all the acute toxicity (100%) of all samples except those from pond 1A of Suncor. In pond 1A, organic ``acids`` accounted for approximately 55--60% of the acute toxicity, nonpolar organic volatile compounds accounted for approximately 20--35% and the balance of the acute toxicity was due to non-polar organic compounds that were neither volatile nor organic ``acids``, as removed by precipitation at pH 2.5.

  11. Acute toxicity of methyl mercury to the larval lamprey, Petromyzon marinus

    SciTech Connect

    Mallatt, J.; Barron, M.G.; McDonough, C.

    1986-08-01

    Mercury compounds pollute many aquatic habitats and are extremely toxic to aquatic organisms. Acute toxicity of waterborne methyl mercury has been studied in several teleost species. Lampreys are taxonomically distant from teleosts and are used for comparative toxicological purposes. Landlocked sea lampreys, Petromyzon marinus, inhabit the Great Lakes region, and their larvae (ammocoetes) burrow in stream sediments. In this study, the authors present toxicity curves for ammocoetes exposed acutely to methyl mercuric chloride solutions. Susceptibility was related to temperature and animal size.

  12. Potential contribution of inorganic ions to whole effluent acute toxicity and genotoxicity during sewage tertiary treatment.

    PubMed

    Sun, Jian; Quan, Ying; Wang, Wei; Zheng, Shaokui; Liu, Xinchun

    2015-09-15

    Two acute toxicity tests (luminescent bacteria assay and cladoceran assay) and one genotoxicity test (broad bean assay) were used to evaluate whole effluent toxicity during the standard anion exchange resin-based pilot-scale sewage tertiary treatment that stably achieved significant dissolved organic carbon and inorganic ions reduction. The effect of six representative inorganic ions (i.e., Cl(-), SO4(2-), NO3(-)-N, NO2(-)-N, NH4(+)-N and PO4(3-)-P) on the acute toxicity and genotoxicity was further investigated. Significant whole effluent genotoxicity reduction was observed as an ∼ 57% micronucleated cell frequency reduction and ∼ 46% mitotic index increment during the pilot-scale periods, which should be attributed to significant organic removal since no significant (p ≥ 0.116) increase in genotoxicity was observed with the increase in these ionic concentrations. However, no significant (p ≥ 0.14) reductions were observed for whole effluent acute toxicity using two acute toxicity assays during the pilot-scale periods, and these inorganic ions, especially NH4(+)-N, contributed considerably to the acute toxicity. Based on Pearson correlation coefficients, whole effluent acute toxicity showed significant positive (p < 0.001, r ≥ 0.758) correlations with the NH4(+)-N concentration. Two optimal models were finally developed using step-wise multiple linear regression to predict the whole effluent acute toxicity via NH4(+)-N concentrations.

  13. Toxic Effects of Zinc Chloride on the Bone Development in Danio rerio (Hamilton, 1822).

    PubMed

    Salvaggio, Antonio; Marino, Fabio; Albano, Marco; Pecoraro, Roberta; Camiolo, Giuseppina; Tibullo, Daniele; Bramanti, Vincenzo; Lombardo, Bianca M; Saccone, Salvatore; Mazzei, Veronica; Brundo, Maria V

    2016-01-01

    The increase of heavy metals in the environment involves a high exposure of aquatic organisms to these pollutants. The present study is planned to investigate the effects of zinc chloride (ZnCl2) on the bone embryonic development of Danio rerio and confirm the use of zebrafish as a model organism to study the teratogenic potential of this pollutant. Zebrafish embryos were exposed to different ZnCl2 concentrations and analyzed by ICP-MS. The skeletal anomalies were evaluated to confocal microscope after staining with calcein solution and RhodZin(TM)-3,AM. The data show a delay in hatching compared with the controls, malformations in the process of calcification and significant defects in growth. In conclusion, the current work demonstrates for the first time the Zn toxic effects on calcification process and confirm zebrafish (Danio rerio) as suitable alternative vertebrate model to study the causes and the mechanisms of the skeletal malformations.

  14. Toxicity mechanism of titanium dioxide and zinc oxide nanoparticles against food pathogens.

    PubMed

    Venkatasubbu, G Devanand; Baskar, R; Anusuya, T; Seshan, C Arun; Chelliah, Ramachandran

    2016-12-01

    Food preservation is an important field of research. It extends the shelf life of major food products. Our current study is based on food preservation through TiO2 and ZnO nanoparticles. TiO2 and ZnO are biocompatible nanomaterial. The biocompatibility of the materials were established through toxicity studies on cell lines. Titanium dioxide and Zinc Oxide nanoparticle were synthesized by wet chemical process. They are characterized by X-Ray diffraction and TEM. The antibacterial activities of both the materials were analysed to ensure their effectiveness as food preservative against Salmonella typhi, Klebsiella pneumoniae and Shigella flexneri. The results indicates that TiO2 and ZnO nanoparticle inhibits Salmonella, Klebsiella and Shigella. The mode of action is by the generation of ROS in cases of Salmonella, Klebsiella. Mode of action in Shigella is still unclear. It was also proved that TiO2 and ZnO nanoparticle are biocompatible materials.

  15. Toxic Effects of Zinc Chloride on the Bone Development in Danio rerio (Hamilton, 1822)

    PubMed Central

    Salvaggio, Antonio; Marino, Fabio; Albano, Marco; Pecoraro, Roberta; Camiolo, Giuseppina; Tibullo, Daniele; Bramanti, Vincenzo; Lombardo, Bianca M.; Saccone, Salvatore; Mazzei, Veronica; Brundo, Maria V.

    2016-01-01

    The increase of heavy metals in the environment involves a high exposure of aquatic organisms to these pollutants. The present study is planned to investigate the effects of zinc chloride (ZnCl2) on the bone embryonic development of Danio rerio and confirm the use of zebrafish as a model organism to study the teratogenic potential of this pollutant. Zebrafish embryos were exposed to different ZnCl2 concentrations and analyzed by ICP-MS. The skeletal anomalies were evaluated to confocal microscope after staining with calcein solution and RhodZinTM-3,AM. The data show a delay in hatching compared with the controls, malformations in the process of calcification and significant defects in growth. In conclusion, the current work demonstrates for the first time the Zn toxic effects on calcification process and confirm zebrafish (Danio rerio) as suitable alternative vertebrate model to study the causes and the mechanisms of the skeletal malformations. PMID:27199768

  16. Comparative Cytogenetic Study on the Toxicity of Magnetite and Zinc Ferrite Nanoparticles in Sunflower Root Cells

    NASA Astrophysics Data System (ADS)

    Foca-nici, Ecaterina; Capraru, Gabriela; Creanga, Dorina

    2010-12-01

    In this experimental study the authors present their results regarding the cellular division rate and the percentage of chromosomal aberrations in the root meristematic cells of Helianthus annuus cultivated in the presence of different volume fractions of magnetic nanoparticle suspensions, ranging between 20 and 100 microl/l. The aqueous magnetic colloids were prepared from chemically co-precipitated ferrites coated in sodium oleate. Tissue samples from the root meristeme of 2-3 day old germinated seeds were taken to prepare microscope slides following Squash method combined with Fuelgen techniques. Microscope investigation (cytogenetic tests) has resulted in the evaluation of mitotic index and chromosomal aberration index that appeared diminished and respectively increased following the addition of magnetic nanoparticles in the culture medium of the young seedlings. Zinc ferrite toxic influence appeared to be higher than that of magnetite, according to both cytogenetic parameters.

  17. The Role of Zinc Sulfate in Acute Bronchiolitis in Patients Aged 2 to 23 Months

    PubMed Central

    Heydarian, Farhad; Behmanesh, Fatemeh; Daluee, Mohammadkhaje; Kianifar, Hamidreza; Hematian, Mohammadnasir

    2011-01-01

    Objective Evaluating the effect of zinc sulfate in improving the clinical manifestations of acute bronchiolitis in children younger than 2 years. Methods This was a double blind pilot trial on 50 patients aged 2 to 23 months at Ghaem and Dr. Sheikh Hospitals in Mashhad from January 2008 to March 2009. Patients were randomly divided into two groups: a case group received oral zinc sulfate and to the control group was given placebo. Findings Mean age of case group was 168.0±108.6 days and control group 169.2±90.4 days (P=0.98) with male predominance in both groups. At first there was no statistically significant difference between the two groups in reducing the symptoms. But 24 hours after treating, improvement of some important manifestations including tachypnea, subcostal and intercostal retraction, wheezing and cyanosis revealed statistically significant difference in control group in comparison with case group (P=0.04). Conclusion Zinc sulfate has no benefit in improving clinical manifestations of acute bronchiolitis. PMID:23056793

  18. Selected chemical characteristics and acute toxicity of urban stormwater, streamflow, and bed material, Maricopa County, Arizona

    USGS Publications Warehouse

    Lopes, T.J.; Fossum, K.D.

    1995-01-01

    Statistical analyses indicated that urban stormwater could degrade the quality of streamflow because of oil and grease, pesticides, dissolved trace metals, and ammonia in stormwater. Ammonia, lead, cadmium, and zinc are released by urban activities and accumulate in bed material. Ammonia could be from fertilizers, fecal matter, and other sources. Lead is probably from vehicles that use leaded gasoline. Cadmium and zinc could be from particulate metal in oil, brake pads, and other sources. Samples of the initial runoff from urban drainage basins appeared to be more toxic than flow-weighted composite samples, and stormwater was more harmful to fathead minnows than to Ceriodaphnia dubia. Streamflow samples from the Salt River were not toxic to either species. The sensitivity of fathead minnows to urban stormwater from most urban drainage basins indicated that the toxicants were detrimental to fish and could be present in stormwater throughout Phoenix. Results of toxicity identification evaluations indicated the toxicity was mostly due to organic constituents. Mortality, however, did not correlate with organophosphate pesticide concentrations. Surfactants and (or) other constituents leached from asphalt could be toxic. The most toxic bed-material samples were collected from an undeveloped drainage basin. Within urban-drainage basins, bed-material samples collected where stormwater accumulates appeared to be more toxic than samples collected from areas unaffected by stormwater. Mortality rates correlated with recoverable concentrations of zinc, copper, and cadmium; however these rates correlated poorly with pesticide concentrations. The bioavailability of trace metals appeared to be controlled by the adsorption properties of bed material.

  19. Tungsten speciation and toxicity: acute toxicity of mono- and poly-tungstates to fish.

    PubMed

    Strigul, Nikolay; Koutsospyros, Agamemnon; Christodoulatos, Christos

    2010-02-01

    Tungsten is a widely used transition metal for which very limited information on environmental and toxicological effects is available. Of particular interest is the lack of information linking tungsten speciation and environmental effects. Tungsten anions may polymerize (depending upon concentration, pH, and aquatic geochemistry) in aquatic and soil systems. However, to this date, of all soluble tungstate species only monotungstates have been scrutinized to a fair extent in toxicological studies. The objective of this work is a comparative assessment of the acute toxicity of monotungstates (sodium tungstate, Na(2)WO(4)) and polytungstates (sodium metatungstate, 3Na(2)WO(4).9WO(3)) to Poecilia reticulate. The experiments have been performed according to the OEDC protocols 203 and 204. LD50 values for 1-14 days show that sodium metatungstate is significantly more toxic to fish than sodium tungstate. Based on LD50 (0.86-3.88gL(-1) or 4.67-21.1x10(-3)molNa(2)WO(4)L(-1)), sodium tungstate may be classified as a chemical of low toxicity to fish. Sodium metatungstate caused similar fish mortality to sodium tungstate when it was introduced in 55-80 times lower concentrations (in terms of molL(-1)) than sodium tungstate. LD50 values for sodium metatungstate range from 0.13 to 0.85gWL(-1) or 5.69 to 38.71x10(-5)mol 3Na(2)WO(4).9WO(3)L(-1). Based on these values sodium metatungstate can be classified as a moderate toxic agent to fish.

  20. Systematic Review of the Relationship between Acute and Late Gastrointestinal Toxicity after Radiotherapy for Prostate Cancer

    PubMed Central

    Peach, Matthew Sean; Showalter, Timothy N.; Ohri, Nitin

    2015-01-01

    A small but meaningful percentage of men who are treated with external beam radiation therapy for prostate cancer will develop late gastrointestinal toxicity. While numerous strategies to prevent gastrointestinal injury have been studied, clinical trials concentrating on late toxicity have been difficult to carry out. Identification of subjects at high risk for late gastrointestinal injury could allow toxicity prevention trials to be performed using reasonable sample sizes. Acute radiation therapy toxicity has been shown to predict late toxicity in several organ systems. Late toxicities may occur as a consequential effect of acute injury. In this systematic review of published reports, we found that late gastrointestinal toxicity following prostate radiotherapy seems to be statistically and potentially causally related to acute gastrointestinal morbidity as a consequential effect. We submit that acute gastrointestinal toxicity may be used to identify at-risk patients who may benefit from additional attention for medical interventions and close follow-up to prevent late toxicity. Acute gastrointestinal toxicity could also be explored as a surrogate endpoint for late effects in prospective trials. PMID:26697225

  1. Cost-effectiveness of zinc as adjunct therapy for acute childhood diarrhoea in developing countries.

    PubMed Central

    Robberstad, Bjarne; Strand, Tor; Black, Robert E.; Sommerfelt, Halvor

    2004-01-01

    OBJECTIVE: To analyse the incremental costs, effects and cost-effectiveness of zinc used as adjunct therapy to standard treatment of acute childhood diarrhoea, including dysentery, and to reassess the cost-effectiveness of standard case management with oral rehydration salt (ORS). METHODS: A decision tree was used to model expected clinical outcomes and expected costs under four alternative treatment strategies. The best available epidemiological, clinical and economic evidence was used in the calculations, and the United Republic of Tanzania was the reference setting. Probabilistic cost-effectiveness analysis was performed using a Monte-Carlo simulation technique and the potential impacts of uncertainty in single parameters were explored in one-way sensitivity analyses. FINDINGS: ORS was found to be less cost-effective than previously thought. The use of zinc as adjunct therapy significantly improved the cost-effectiveness of standard management of diarrhoea for dysenteric as well as non-dysenteric illness. The results were particularly sensitive to mortality rates in non-dysenteric diarrhoea, but the alternative interventions can be defined as highly cost-effective even in pessimistic scenarios. CONCLUSION: There is sufficient evidence to recommend the inclusion of zinc into standard case management of both dysenteric and non-dysenteric acute diarrhoea.A direct transfer of our findings from the United Republic of Tanzania to other settings is not justified, but there are no indications of large geographical differences in the efficacy of zinc. It is therefore plausible that our findings are also applicable to other developing countries. PMID:15500284

  2. Acute pulmonary toxicity of urban particulate matter and ozone.

    PubMed Central

    Vincent, R.; Bjarnason, S. G.; Adamson, I. Y.; Hedgecock, C.; Kumarathasan, P.; Guénette, J.; Potvin, M.; Goegan, P.; Bouthillier, L.

    1997-01-01

    We have investigated the acute lung toxicity of urban particulate matter in interaction with ozone. Rats were exposed for 4 hours to clean air, ozone (0.8 ppm), the urban dust EHC-93 (5 mg/m3 or 50 mg/m3), or ozone in combination with urban dust. The animals were returned to clean air for 32 hours and then injected (intraperitoneally) with [3H]thymidine to label proliferating cells and killed after 90 minutes. The lungs were fixed by inflation, embedded in glycol methacrylate, and processed for light microscopy autoradiography. Cell labeling was low in bronchioles (0.14 +/- 0.04%) and parenchyma (0.13 +/- 0.02%) of air control animals. Inhalation of EHC-93 alone did not induce cell labeling. Ozone alone increased (P < 0.05) cell labeling (bronchioles, 0.42 +/- 0.16%; parenchyma, 0.57 +/- 0.21%), in line with an acute reparative cell proliferation. The effects of ozone were clearly potentiated by co-exposure with either the low (3.31 +/- 0.31%; 0.99 +/- 0.18%) or the high (4.45 +/- 0.51%; 1.47 +/- 0.18%) concentrations of urban dust (ozone X EHC-93, P < 0.05). Cellular changes were most notable in the epithelia of terminal bronchioles and alveolar ducts and did not distribute to the distal parenchyma. Enhanced DNA synthesis indicates that particulate matter from ambient air can exacerbate epithelial lesions in the lungs. This may extend beyond air pollutant interactions, such as to effects of inhaled particles in the lungs of compromised individuals. Images Figure 1 PMID:9403707

  3. Toxicity of chromium (VI) to two mussels and an amphipod in water-only exposures with or without a co-stressor of elevated temperature, zinc, or nitrate

    USGS Publications Warehouse

    Wang, Ning; Kunz, James L.; Ivey, Chris D.; Ingersoll, Christopher G.; Barnhart, M. Christopher; Glidewell, Elizabeth A.

    2017-01-01

    The objectives of the present study were to develop methods for propagating western pearlshell (Margaritifera falcata) for laboratory toxicity testing and evaluate acute and chronic toxicity of chromium VI [Cr(VI)] to the pearlshell and a commonly tested mussel (fatmucket, Lampsilis siliquoidea at 20 °C or in association with a co-stressor of elevated temperature (27 °C), zinc (50 µg Zn/L), or nitrate (35 mg NO3/L). A commonly tested invertebrate (amphipod, Hyalella azteca) also was tested in chronic exposures. Newly transformed pearlshell (~1 week old) were successfully cultured and tested in acute 96 h Cr exposures (control survival 100%). However, the grow-out of juveniles in culture for chronic toxicity testing was less successful and chronic 28-day Cr toxicity tests started with 4 month-old pearlshell failed due to low control survival (39–68%). Acute median effect concentration (EC50) for the pearlshell (919 µg Cr/L) and fatmucket (456 µg Cr/L) tested at 20 °C without a co-stressor decreased by a factor of > 2 at elevated temperature but did not decrease at elevated Zn or elevated NO3. Chronic 28-day Cr tests were completed successfully with the fatmucket and amphipod (control survival 83–98%). Chronic maximum acceptable toxicant concentration (MATC) for fatmucket at 20 °C (26 µg Cr/L) decreased by a factor of 2 at elevated temperature or NO3 but did not decrease at elevated Zn. However, chronic MATC for amphipod at 20 °C (13 µg Cr/L) did not decrease at elevated temperature, Zn, or NO3. Acute EC50s for both mussels tested with or without a co-stressor were above the final acute value used to derive United States Environmental Protection Agency acute water quality criterion (WQC) for Cr(VI); however, chronic MATCs for fatmucket at elevated temperature or NO3 and chronic MATCs for the amphipod at 20 °C with or without elevated Zn or NO3 were about equal to the chronic WQC. The results indicate that (1) the elevated temperature

  4. Safety evaluation of Se-methylselenocysteine as nutritional selenium supplement: acute toxicity, genotoxicity and subchronic toxicity.

    PubMed

    Yang, Hui; Jia, Xudong

    2014-12-01

    The significant toxicity of selenium emphasizes the need to assess the health risk of various selenocompounds as nutritional supplements. Se-methylselenocysteine (SeMC) was recently reported to be more bioactive but the toxicological effects have not been sufficiently characterized. This study aimed to evaluate the safety of SeMC and provide the Acceptable Daily Intake (ADI) for its use in human diet. Our results demonstrated that SeMC, with the Median Lethal Dose (LD50) of 12.6 and 9.26mg/kg BW in female and male mice, was of high potent of health hazard under acute oral exposure, but a battery of tests including Ames test, micronucleus assay and mouse sperm malformation assay suggested that SeMC was not genotoxic. The repeated dose study indicated little systemic toxicity of SeMC at supernutritional levels (0.5, 0.7, 0.9mg/kg BW/day) after 90-day oral exposure. Importantly, the 95% lower confidence value of Benchmark Dose (BMDL) was estimated as 0.34mg/kg BW/day according to the elevated relative liver weight. The ADI for human was established at 3.4μg/kg BW/day. The results suggested greater safety of SeMC as a nutritional selenium supplement, but health risk needs to be further evaluated when SeMC is applied beyond this level to achieve cancer chemoprevention.

  5. Zinc Supplementation with Polaprezinc Protects Mouse Hepatocytes against Acetaminophen-Induced Toxicity via Induction of Heat Shock Protein 70

    PubMed Central

    Nishida, Tadashi; Ohata, Shuzo; Kusumoto, Chiaki; Mochida, Shinsuke; Nakada, Junya; Inagaki, Yoshimi; Ohta, Yoshiji; Matsura, Tatsuya

    2010-01-01

    Polaprezinc, a chelate compound consisting of zinc and l-carnosine, is clinically used as a medicine for gastric ulcers. It has been shown that induction of heat shock protein (HSP) is involved in protective effects of polaprezinc against gastric mucosal injury. In the present study, we investigated whether polaprezinc and its components could induce HSP70 and prevent acetaminophen (APAP) toxicity in mouse primary cultured hepatocytes. Hepatocytes were treated with polaprezinc, zinc sulfate or l-carnosine at the concentration of 100 µM for 9 h, and then exposed to 10 mM APAP. Polaprezinc or zinc sulfate increased cellular HSP70 expression. However, l-carnosine had no influence on it. Pretreatment of the cells with polaprezinc or zinc sulfate significantly suppressed cell death as well as cellular lipid peroxidation after APAP treatment. In contrast, pretreatment with polaprezinc did not affect decrease in intracellular glutathione after APAP. Furthermore, treatment with KNK437, an HSP inhibitor, attenuated increase in HSP70 expression induced by polaprezinc, and abolished protective effect of polaprezinc on cell death after APAP. These results suggested that polaprezinc, in particular its zinc component, induces HSP70 expression in mouse primary cultured hepatocytes, and inhibits lipid peroxidation after APAP treatment, resulting in protection against APAP toxicity. PMID:20104264

  6. Preparation of Zeolite/Zinc Oxide Nanocomposites for toxic metals removal from water

    NASA Astrophysics Data System (ADS)

    Alswata, Abdullah A.; Ahmad, Mansor Bin; Al-Hada, Naif Mohammed; Kamari, Halimah Mohamed; Hussein, Mohd Zobir Bin; Ibrahim, Nor Azowa

    This research work has proposed preparation of Zeolite/Zinc Oxide Nanocomposite (Zeolite/ZnO NCs) by using a co-precipitation method. Then, the prepared Nanocomposite has been tested for adsorption of Lead Pb (II) and Arsenic As (V) from aqueous solution under the room pressure and temperature. After that, the prepared adsorbent has been studied by several techniques. For adsorption process; the effect of the adsorbent masses, contact time, PH and initial metals concentration as well as, the kinetics and isotherm for adsorption process have been investigated. The results revealed that; ZnO nanoparticles (NPs) with average diameter 4.5 nm have successfully been loaded into Zeolite. The optimum parameters for the removal of the toxic metals 93% and 89% of Pb (II) and As (V), respectively, in 100 mg/L aqua solutions were pH4, 0.15 g and 30 min. According to the obtained results; pseudo second-order kinetic and Langmuir isotherm model have higher correlation coefficients and provided a better agreement with the experimental data. The prepared sorbent showed an economical and effective way to remove the heavy toxic metals due to its ambient operation conditions, low- consumption energy and facile regeneration method.

  7. Bromobenzene-induced lethal toxicity in mouse is prevented by pretreatment with zinc sulfate.

    PubMed

    Yoshioka, Hiroki; Fukaya, Shiori; Fukuishi, Nobuyuki; Nagatsu, Akito; Nonogaki, Tsunemasa; Onosaka, Satomi

    2016-07-25

    In the current study, we evaluated the protective effect of zinc (Zn) against bromobenzene (BB) -induced lethal toxicity. We used Zn because this element is known to be an inducer of metallothionein (MT), which is in turn known to serve as an endogenous scavenger of free radicals. We administered Zn (as ZnSO4) at 50 mg/kg subcutaneously once-daily for 3 successive days prior to a single intraperitoneal administration of 1.2 g/kg BB in male ddY mice. Our results showed that pretreatment with Zn completely abolished the BB-induced mortality of mice until 48 h. We also found that pretreatment of mice with Zn significantly decreased the functional marker levels and reduced the histological damage both in liver and kidney as assessed at 18 h post-BB. We also showed that pretreatment with Zn enhanced antioxidative activity, resulting in decreased lipid peroxidation in both liver and kidney. Moreover, BB-induced calcium levels were downregulated by pretreatment with Zn. In addition, Zn-induced MT was decreased in Zn + BB-treated animals, implying that MT was consumed by BB-induced radicals. These findings suggest that prophylaxis with Zn protects mice from BB-induced lethal toxicity by decreasing oxidative stress in liver and kidney, presumably by induction of MT, which scavenges radicals induced by BB exposure.

  8. Severe Acute Pulmonary Toxicity Associated with Brentuximab in a Patient with Refractory Hodgkin's Lymphoma

    PubMed Central

    Sabet, Yasmin; Ramirez, Saul; Rosell Cespedes, Elizabeth; Rensoli Velasquez, Marimer; Porres-Muñoz, Mateo; Gaur, Sumit; Figueroa-Casas, Juan B.; Porres-Aguilar, Mateo

    2016-01-01

    Acute pulmonary toxicity associated with brentuximab appears to be a rare but serious adverse effect that can be potentially fatal. We report the case of a twenty-nine-year-old female with Hodgkin's lymphoma who was treated with brentuximab and later presented with severe acute pulmonary toxicity; she improved after the discontinuation of brentuximab and administration of antibiotics and glucocorticoid therapy. Currently there is very little data in the literature in regard to the clinical manifestations and characteristics of patients taking brentuximab and the potential development of acute severe pulmonary toxicity, as well as the appropriate therapeutic approach, making this particular case of successful treatment and resolution unique. PMID:27190667

  9. Acute toxicity of biodiesel to freshwater and marine organisms

    SciTech Connect

    Reece, D.; Peterson, C.

    1995-11-01

    Biodiesel fuels are reported to be nontoxic resulting in less potential hazard to fish and other aquatic life in case of accidental spills. This paper reports on static tests with rapeseed methyl ester (RME) and rapeseed ethyl ester (REE) performed according to EPA/600/4-90/027. The acute aquatic toxicity tests were conducted with both rainbow trout and daphnia magna by CH2M Hill in Corvallis, Oregon under contract to the University of Idaho. The LC50 (the point at which 50% have died and 50% are still alive determined by interpolation) values for each of the substrates tested with daphnia magna in parts per million were as follows: control(table salt (NaCl)) = 3.7, D2 = 1.43, RME = 23, REE = 99, and Methyl Soyate = 332. Duplicate tests with rainbow trout were run with 10 organisms per replicate. LC50 numbers were not reported because of the failure to kill a sufficient number of fish at the concentrations tested, even with the diesel control fuel. The 20 percent and 50 percent blends had scattered losses of fish but none of the tests had less than 85 percent survival at any concentrations after 96 hours.

  10. Pathology of acute 3-acetyldeoxynivalenol toxicity in mice.

    PubMed Central

    Schiefer, H B; Nicholson, S; Kasali, O B; Hancock, D S; Greenhalgh, R

    1985-01-01

    Mice were killed 2, 4, 6, 12, 24, 48 and 96 hours after intragastrical administration of 0, 5, 10, 20, or 40 mg/kg body weight of 3-acetyldeoxynivalenol. The animals became clinically ill after 12 hours and some animals in the highest dose group died. Histological examination of duodenal crypts, thymus and spleen revealed, in all dose groups, presence of the characteristic lesions that are known to be produced by trichothecenes, but the intensity of lesions in the 40 mg group corresponded to lesions known to be caused by 4 mg/kg of T-2 toxin. A rabbit skin bioassay with 3-acetyldeoxynivalenol gave negative results on one occasion and a mild reaction to 100 to 500 micrograms/mL on another. It is concluded that 3-acetyldeoxynivalenol is considerably less toxic than T-2 toxin, but causes acute effects in the dividing cells of the body in a manner characteristic of trichothecenes. Images Fig. 1a. Fig. 1b. Fig. 2. Fig. 3. PMID:4041976

  11. Developmental Toxicity of Zinc Oxide Nanoparticles to Zebrafish (Danio rerio): A Transcriptomic Analysis

    PubMed Central

    Choi, Jin Soo; Kim, Ryeo-Ok; Yoon, Seokjoo

    2016-01-01

    Zinc oxide nanoparticles (ZnO NPs) are being utilized in an increasing number of fields and commercial applications. While their general toxicity and associated oxidative stress have been extensively studied, the toxicological pathways that they induce in developmental stages are still largely unknown. In this study, the developmental toxicity of ZnO NPs to embryonic/larval zebrafish was investigated. The transcriptional expression profiles induced by ZnO NPs were also investigated to ascertain novel genomic responses related to their specific toxicity pathway. Zebrafish embryos were exposed to 0.01, 0.1, 1, and 10 mg/L ZnO NPs for 96 h post-fertilization. The toxicity of ZnO NPs, based on their Zn concentration, was quite similar to that in embryonic/larval zebrafish exposed to corresponding ZnSO4 concentrations. Pericardial edema and yolk-sac edema were the principal malformations induced by ZnO NPs. Gene-expression profiling using microarrays demonstrated 689 genes that were differentially regulated (fold change >1.5) following exposure to ZnO NPs (498 upregulated, 191 downregulated). Several genes that were differentially regulated following ZnO NP exposure shared similar biological pathways with those observed with ZnSO4 exposure, but six genes (aicda, cyb5d1, edar, intl2, ogfrl2 and tnfsf13b) associated with inflammation and the immune system responded specifically to ZnO NPs (either in the opposite direction or were unchanged in ZnSO4 exposure). Real-time reverse-transcription quantitative polymerase chain reaction confirmed that the responses of these genes to ZnO NPs were significantly different from their response to ZnSO4 exposure. ZnO NPs may affect genes related to inflammation and the immune system, resulting in yolk-sac edema and pericardia edema in embryonic/larval developmental stages. These results will assist in elucidating the mechanisms of toxicity of ZnO NPs during development of zebrafish. PMID:27504894

  12. Importance of structural information in predicting human acute toxicity from in vitro cytotoxicity data

    SciTech Connect

    Lee, Soyoung; Park, Keunwan; Ahn, Hee-Sung; Kim, Dongsup

    2010-07-15

    In this study, we tried to assess the utility of the structural information of drugs for predicting human acute toxicity from in vitro basal cytotoxicity, and to interpret the informative quality and the pharmacokinetic meaning of each structural descriptor. For this, human acute toxicity data of 67 drugs were taken from literature with their basal cytotoxicity data, and used to develop predictive models. A series of multiple linear regression analyses were performed to construct feasible regression models by combining molecular descriptors and cytotoxicity data. We found that although the molecular descriptors alone had only moderate correlation with human acute toxicity, they were highly useful for explaining the discrepancy between in vitro cytotoxicity and human acute toxicity. Among many possible models, we selected the most explanatory models by changing the number and the type of combined molecular descriptors. The results showed that our selected models had high predictive power (R{sup 2}: between 0.7 and 0.87). Our analysis indicated that those successful models increased the prediction accuracies by providing the information on human pharmacokinetic parameters which are the major reason for the difference between human acute toxicity and cytotoxicity. In addition, we performed a clustering analysis on selected molecular descriptors to assess their informative qualities. The results indicated that the number of single bonds, the number of hydrogen bond donors and valence connectivity indices are closely related to linking cytotoxicity to acute toxicity, which provides insightful explanation about human toxicity beyond cytotoxicity.

  13. Results of acute and chronic toxicity tests conducted at SRS NPDES outfalls, July--October 1991

    SciTech Connect

    Specht, W.L.

    1992-01-01

    Acute (48 hour LC50) and chronic (7-day reproductive impairment) toxicity tests were conducted on Ceriodaphnia dubia in water collected from 53 NPDES outfalls. All tests were conducted at the in-stream waste concentration. only 12 of the 53 outfalls showed no evidence of toxicity. Twenty-eight of the outfalls were acutely toxic, often producing 100% mortality during the first day of exposure. Fourteen outfalls had no discharge at the time of sampling and could not be tested. Three outfalls were not tested because their toxicity has been adequately characterized in other investigations. Elevated concentrations of total residual chlorine are suspected to be responsible for the observed toxicity of many NPDES outfalls, particularly the sanitary wastewater treatment plants. Chemical data from previous studies indicate that metals may also be present in toxic concentrations at many outfalls. Toxicity identification and reduction options are discussed.

  14. The influence of natural organic matter and aging on suspension stability in guideline toxicity testing of silver, zinc oxide, and titanium dioxide nanoparticles with Daphnia magna.

    PubMed

    Cupi, Denisa; Hartmann, Nanna B; Baun, Anders

    2015-03-01

    The present study investigated changes in suspension stability and ecotoxicity of engineered nanoparticles (ENPs) by addition of Suwannee River natural organic matter and aging of stock and test suspensions prior to testing. Acute toxicity tests of silver (Ag), zinc oxide (ZnO), and titanium dioxide (TiO2 ) ENPs with Daphnia magna were carried out following Organisation for Economic Co-operation and Development test guidelines. Daphnia magna was found to be very sensitive to Ag ENPs (48-h 50% effective concentration 33 μg L(-1) ), and aging of the test suspensions in M7 medium (up to 48 h) did not decrease toxicity significantly. Conversely, the presence of Suwannee River natural organic matter (NOM; 20 mg L(-1) ) completely alleviated Ag ENP toxicity in all testing scenarios and did not aid in stabilizing suspensions. In contrast, addition of Suwannee River NOM stabilized ZnO ENP suspensions and did not decrease toxicity. Aging for 48 h generated monotonous concentration-response curves in the presence and absence of Suwannee River NOM. At concentrations up to 100 mg L(-1) TiO2 ENPs did not cause immobilization of D. magna under any of the tested conditions. Presence of Suwannee River NOM caused agglomeration in stock suspensions. The authors' results suggest that aging and presence of Suwannee River NOM are important parameters in standard toxicity testing of ENPs, which in some cases may aid in gaining better control over the exposure conditions but in other cases might contribute to agglomeration or elimination of ENP toxicity. Therefore, modifications to the current guidelines for testing ENPs should be evaluated on a case-by-case basis. Environ Toxicol Chem 2015;34:497-506. © 2014 SETAC.

  15. Toxicity of sediments from lead-zinc mining areas to juvenile freshwater mussels (Lampsilis siliquoidea) compared to standard test organisms.

    PubMed

    Besser, John M; Ingersoll, Christopher G; Brumbaugh, William G; Kemble, Nile E; May, Thomas W; Wang, Ning; MacDonald, Donald D; Roberts, Andrew D

    2015-03-01

    Sediment toxicity tests compared chronic effects on survival, growth, and biomass of juvenile freshwater mussels (28-d exposures with Lampsilis siliquoidea) to the responses of standard test organisms-amphipods (28-d exposures with Hyalella azteca) and midges (10-d exposures with Chironomus dilutus)-in sediments from 2 lead-zinc mining areas: the Tri-State Mining District and Southeast Missouri Mining District. Mussel tests were conducted in sediments sieved to <0.25 mm to facilitate recovery of juvenile mussels (2-4 mo old). Sediments were contaminated primarily with lead, zinc, and cadmium, with greater zinc and cadmium concentrations in Tri-State sediments and greater lead concentrations in southeast Missouri sediments. The frequency of highly toxic responses (reduced 10% or more relative to reference sites) in Tri-State sediments was greatest for amphipod survival (25% of samples), midge biomass (20%), and mussel survival (14%). In southeast Missouri sediments, the frequency of highly toxic samples was greatest for mussel biomass (25%) and amphipod biomass (13%). Thresholds for metal toxicity to mussels, expressed as hazard quotients based on probable effect concentrations, were lower for southeast Missouri sediments than for Tri-State sediments. Southeast Missouri sites with toxic sediments had 2 or fewer live mussel taxa in a concurrent mussel population survey, compared with 7 to 26 taxa at reference sites. These results demonstrate that sediment toxicity tests with juvenile mussels can be conducted reliably by modifying existing standard methods; that the sensitivity of mussels to metals can be similar to or greater than standard test organisms; and that responses of mussels in laboratory toxicity tests are consistent with effects on wild mussel populations.

  16. Toxicity of sediments from lead-zinc mining areas to juvenile freshwater mussels (Lampsilis siliquoidea) compared to standard test organisms

    USGS Publications Warehouse

    Besser, John M.; Ingersoll, Christopher G.; Brumbaugh, William G.; Kemble, Nile E.; May, Thomas W.; Wang, Ning; MacDonald, Donald D.; Roberts, Andrew D.

    2015-01-01

    Sediment toxicity tests compared chronic effects on survival, growth, and biomass of juvenile freshwater mussels (28-d exposures with Lampsilis siliquoidea) to the responses of standard test organisms—amphipods (28-d exposures with Hyalella azteca) and midges (10-d exposures with Chironomus dilutus)—in sediments from 2 lead–zinc mining areas: the Tri-State Mining District and Southeast Missouri Mining District. Mussel tests were conducted in sediments sieved to <0.25 mm to facilitate recovery of juvenile mussels (2–4 mo old). Sediments were contaminated primarily with lead, zinc, and cadmium, with greater zinc and cadmium concentrations in Tri-State sediments and greater lead concentrations in southeast Missouri sediments. The frequency of highly toxic responses (reduced 10% or more relative to reference sites) in Tri-State sediments was greatest for amphipod survival (25% of samples), midge biomass (20%), and mussel survival (14%). In southeast Missouri sediments, the frequency of highly toxic samples was greatest for mussel biomass (25%) and amphipod biomass (13%). Thresholds for metal toxicity to mussels, expressed as hazard quotients based on probable effect concentrations, were lower for southeast Missouri sediments than for Tri-State sediments. Southeast Missouri sites with toxic sediments had 2 or fewer live mussel taxa in a concurrent mussel population survey, compared with 7 to 26 taxa at reference sites. These results demonstrate that sediment toxicity tests with juvenile mussels can be conducted reliably by modifying existing standard methods; that the sensitivity of mussels to metals can be similar to or greater than standard test organisms; and that responses of mussels in laboratory toxicity tests are consistent with effects on wild mussel populations.

  17. Fish embryo toxicity test: identification of compounds with weak toxicity and analysis of behavioral effects to improve prediction of acute toxicity for neurotoxic compounds.

    PubMed

    Klüver, Nils; König, Maria; Ortmann, Julia; Massei, Riccardo; Paschke, Albrecht; Kühne, Ralph; Scholz, Stefan

    2015-06-02

    The fish embryo toxicity test has been proposed as an alternative for the acute fish toxicity test, but concerns have been raised for its predictivity given that a few compounds have been shown to exhibit a weak acute toxicity in the fish embryo. In order to better define the applicability domain and improve the predictive capacity of the fish embryo test, we performed a systematic analysis of existing fish embryo and acute fish toxicity data. A correlation analysis of a total of 153 compounds identified 28 compounds with a weaker or no toxicity in the fish embryo test. Eleven of these compounds exhibited a neurotoxic mode of action. We selected a subset of eight compounds with weaker or no embryo toxicity (cyanazine, picloram, aldicarb, azinphos-methyl, dieldrin, diquat dibromide, endosulfan, and esfenvalerate) to study toxicokinetics and a neurotoxic mode of action as potential reasons for the deviating fish embryo toxicity. Published fish embryo LC50 values were confirmed by experimental analysis of zebrafish embryo LC50 according to OECD guideline 236. Except for diquat dibromide, internal concentration analysis did not indicate a potential relation of the low sensitivity of fish embryos to a limited uptake of the compounds. Analysis of locomotor activity of diquat dibromide and the neurotoxic compounds in 98 hpf embryos (exposed for 96 h) indicated a specific effect on behavior (embryonic movement) for the neurotoxic compounds. The EC50s of behavior for neurotoxic compounds were close to the acute fish toxicity LC50. Our data provided the first evidence that the applicability domain of the fish embryo test (LC50s determination) may exclude neurotoxic compounds. However, neurotoxic compounds could be identified by changes in embryonic locomotion. Although a quantitative prediction of acute fish toxicity LC50 using behavioral assays in fish embryos may not yet be possible, the identification of neurotoxicity could trigger the conduction of a conventional fish

  18. Acute sensitivity of a broad range of freshwater mussels to chemicals with different modes of toxic action.

    PubMed

    Wang, Ning; Ivey, Christopher D; Ingersoll, Christopher G; Brumbaugh, William G; Alvarez, David; Hammer, Edward J; Bauer, Candice R; Augspurger, Tom; Raimondo, Sandy; Barnhart, M Christopher

    2017-03-01

    Freshwater mussels, one of the most imperiled groups of animals in the world, are generally underrepresented in toxicity databases used for the development of ambient water quality criteria and other environmental guidance values. Acute 96-h toxicity tests were conducted to evaluate the sensitivity of 5 species of juvenile mussels from 2 families and 4 tribes to 10 chemicals (ammonia, metals, major ions, and organic compounds) and to screen 10 additional chemicals (mainly organic compounds) with a commonly tested mussel species, fatmucket (Lampsilis siliquoidea). In the multi-species study, median effect concentrations (EC50s) among the 5 species differed by a factor of ≤2 for chloride, potassium, sulfate, and zinc; a factor of ≤5 for ammonia, chromium, copper, and nickel; and factors of 6 and 12 for metolachlor and alachlor, respectively, indicating that mussels representing different families or tribes had similar sensitivity to most of the tested chemicals, regardless of modes of action. There was a strong linear relationship between EC50s for fatmucket and the other 4 mussel species across the 10 chemicals (r(2)  = 0.97, slope close to 1.0), indicating that fatmucket was similar to other mussel species; thus, this commonly tested species can be a good surrogate for protecting other mussels in acute exposures. The sensitivity of juvenile fatmucket among different populations or cultured from larvae of wild adults and captive-cultured adults was also similar in acute exposures to copper or chloride, indicating captive-cultured adult mussels can reliably be used to reproduce juveniles for toxicity testing. In compiled databases for all freshwater species, 1 or more mussel species were among the 4 most sensitive species for alachlor, ammonia, chloride, potassium, sulfate, copper, nickel, and zinc; therefore, the development of water quality criteria and other environmental guidance values for these chemicals should reflect the sensitivity of mussels. In

  19. Acute sensitivity of a broad range of freshwater mussels to chemicals with different modes of toxic action

    USGS Publications Warehouse

    Wang, Ning; Ivey, Chris D.; Ingersoll, Christopher G.; Brumbaugh, William G.; Alvarez, David; Hammer, Edward J.; Bauer, Candice R.; Augspurger, Tom; Raimondo, Sandy; Barnhart, M.Christopher

    2017-01-01

    Freshwater mussels, one of the most imperiled groups of animals in the world, are generally underrepresented in toxicity databases used for the development of ambient water quality criteria and other environmental guidance values. Acute 96-h toxicity tests were conducted to evaluate the sensitivity of 5 species of juvenile mussels from 2 families and 4 tribes to 10 chemicals (ammonia, metals, major ions, and organic compounds) and to screen 10 additional chemicals (mainly organic compounds) with a commonly tested mussel species, fatmucket (Lampsilis siliquoidea). In the multi-species study, median effect concentrations (EC50s) among the 5 species differed by a factor of ≤2 for chloride, potassium, sulfate, and zinc; a factor of ≤5 for ammonia, chromium, copper, and nickel; and factors of 6 and 12 for metolachlor and alachlor, respectively, indicating that mussels representing different families or tribes had similar sensitivity to most of the tested chemicals, regardless of modes of action. There was a strong linear relationship between EC50s for fatmucket and the other 4 mussel species across the 10 chemicals (r2 = 0.97, slope close to 1.0), indicating that fatmucket was similar to other mussel species; thus, this commonly tested species can be a good surrogate for protecting other mussels in acute exposures. The sensitivity of juvenile fatmucket among different populations or cultured from larvae of wild adults and captive-cultured adults was also similar in acute exposures to copper or chloride, indicating captive-cultured adult mussels can reliably be used to reproduce juveniles for toxicity testing. In compiled databases for all freshwater species, 1 or more mussel species were among the 4 most sensitive species for alachlor, ammonia, chloride, potassium, sulfate, copper, nickel, and zinc; therefore, the development of water quality criteria and other environmental guidance values for these chemicals should reflect the sensitivity of mussels. In

  20. Cross-Sector Review of Drivers and Available 3Rs Approaches for Acute Systemic Toxicity Testing

    PubMed Central

    Seidle, Troy; Robinson, Sally; Holmes, Tom; Creton, Stuart; Prieto, Pilar; Scheel, Julia; Chlebus, Magda

    2010-01-01

    Acute systemic toxicity studies are carried out in many sectors in which synthetic chemicals are manufactured or used and are among the most criticized of all toxicology tests on both scientific and ethical grounds. A review of the drivers for acute toxicity testing within the pharmaceutical industry led to a paradigm shift whereby in vivo acute toxicity data are no longer routinely required in advance of human clinical trials. Based on this experience, the following review was undertaken to identify (1) regulatory and scientific drivers for acute toxicity testing in other industrial sectors, (2) activities aimed at replacing, reducing, or refining the use of animals, and (3) recommendations for future work in this area. PMID:20484382

  1. Assessing Contaminant Sensitivity of Endangered and Threatened Aquatic Species: Part I. Acute Toxicity of Five Chemicals

    EPA Science Inventory

    This paper reports on the results of acute toxicity tests conducted with common surrogate species, and several species of threatened and endangered species for which there were excess artificially propagated stock to allow direct testing.

  2. Acute toxicity of selected crude and refined shale oil derived and petroleum-derived substances

    SciTech Connect

    Smith, L.H.; Haschek, W.M.; Witschi, H.

    1980-01-01

    General information was obtained on the toxicity of selected samples of crude Paraho shale oil and some of its derivatives, some crude petroleums, and 3 refined petroleum products. Five tests were used to determine the acute toxicity of these substances: acute lethality in mice following oral or intraperitoneal administration of a single dose; acute dermal toxicity of a single dose in rats; delayed-type allergic contact hypersensitivity in guinea pigs; primary eye irritation and primary skin irritation of a single dose in rabbits. Histopathologic changes induced in mice following intraperitoneal injection of a single large dose of crude shale oil and two of its hydrotreated derivatives were examined. Studies also have been initiated to examine the tumor inducing potential of selected samples. The test system used was the mouse lung adenoma bioassay. The present report describes our findings and shows that all compounds tested have very low or no acute toxic effects in laboratory animals.

  3. Quantitative Structure--Activity Relationship Modeling of Rat Acute Toxicity by Oral Exposure

    EPA Science Inventory

    Background: Few Quantitative Structure-Activity Relationship (QSAR) studies have successfully modeled large, diverse rodent toxicity endpoints. Objective: In this study, a combinatorial QSAR approach has been employed for the creation of robust and predictive models of acute toxi...

  4. Consensus definitions of 14 severe acute toxic effects for childhood lymphoblastic leukaemia treatment: a Delphi consensus.

    PubMed

    Schmiegelow, Kjeld; Attarbaschi, Andishe; Barzilai, Shlomit; Escherich, Gabriele; Frandsen, Thomas Leth; Halsey, Christina; Hough, Rachael; Jeha, Sima; Kato, Motohiro; Liang, Der-Cherng; Mikkelsen, Torben Stamm; Möricke, Anja; Niinimäki, Riitta; Piette, Caroline; Putti, Maria Caterina; Raetz, Elizabeth; Silverman, Lewis B; Skinner, Roderick; Tuckuviene, Ruta; van der Sluis, Inge; Zapotocka, Ester

    2016-06-01

    Although there are high survival rates for children with acute lymphoblastic leukaemia, their outcome is often counterbalanced by the burden of toxic effects. This is because reported frequencies vary widely across studies, partly because of diverse definitions of toxic effects. Using the Delphi method, 15 international childhood acute lymphoblastic leukaemia study groups assessed acute lymphoblastic leukaemia protocols to address toxic effects that were to be considered by the Ponte di Legno working group. 14 acute toxic effects (hypersensitivity to asparaginase, hyperlipidaemia, osteonecrosis, asparaginase-associated pancreatitis, arterial hypertension, posterior reversible encephalopathy syndrome, seizures, depressed level of consciousness, methotrexate-related stroke-like syndrome, peripheral neuropathy, high-dose methotrexate-related nephrotoxicity, sinusoidal obstructive syndrome, thromboembolism, and Pneumocystis jirovecii pneumonia) that are serious but too rare to be addressed comprehensively within any single group, or are deemed to need consensus definitions for reliable incidence comparisons, were selected for assessment. Our results showed that none of the protocols addressed all 14 toxic effects, that no two protocols shared identical definitions of all toxic effects, and that no toxic effect definition was shared by all protocols. Using the Delphi method over three face-to-face plenary meetings, consensus definitions were obtained for all 14 toxic effects. In the overall assessment of outcome of acute lymphoblastic leukaemia treatment, these expert opinion-based definitions will allow reliable comparisons of frequencies and severities of acute toxic effects across treatment protocols, and facilitate international research on cause, guidelines for treatment adaptation, preventive strategies, and development of consensus algorithms for reporting on acute lymphoblastic leukaemia treatment.

  5. Developmental toxicity, acute toxicity and mutagenicity testing in freshwater snails Biomphalaria glabrata (Mollusca: Gastropoda) exposed to chromium and water samples.

    PubMed

    Tallarico, Lenita de Freitas; Borrely, Sueli Ivone; Hamada, Natália; Grazeffe, Vanessa Siqueira; Ohlweiler, Fernanda Pires; Okazaki, Kayo; Granatelli, Amanda Tosatte; Pereira, Ivana Wuo; Pereira, Carlos Alberto de Bragança; Nakano, Eliana

    2014-12-01

    A protocol combining acute toxicity, developmental toxicity and mutagenicity analysis in freshwater snail Biomphalaria glabrata for application in ecotoxicological studies is described. For acute toxicity testing, LC50 and EC50 values were determined; dominant lethal mutations induction was the endpoint for mutagenicity analysis. Reference toxicant potassium dichromate (K2Cr2O7) was used to characterize B. glabrata sensitivity for toxicity and cyclophosphamide to mutagenicity testing purposes. Compared to other relevant freshwater species, B. glabrata showed high sensitivity: the lowest EC50 value was obtained with embryos at veliger stage (5.76mg/L). To assess the model applicability for environmental studies, influent and effluent water samples from a wastewater treatment plant were evaluated. Gastropod sensitivity was assessed in comparison to the standardized bioassay with Daphnia similis exposed to the same water samples. Sampling sites identified as toxic to daphnids were also detected by snails, showing a qualitatively similar sensitivity suggesting that B. glabrata is a suitable test species for freshwater monitoring. Holding procedures and protocols implemented for toxicity and developmental bioassays showed to be in compliance with international standards for intra-laboratory precision. Thereby, we are proposing this system for application in ecotoxicological studies.

  6. Acute toxicity, twenty-eight days repeated dose toxicity and genotoxicity of vanadyl trehalose in kunming mice.

    PubMed

    Jiang, Pingzhe; Ni, Zaizhong; Wang, Bin; Ma, Baicheng; Duan, Huikun; Li, Xiaodan; Ma, Xiaofeng; Wei, Qian; Ji, Xiangzhen; Liu, Qiqi; Xing, Shuguang; Li, Minggang

    2017-04-01

    A new trend has been developed using vanadium and organic ligands to form novel compounds in order to improve the beneficial actions and reduce the toxicity of vanadium compounds. In present study, vanadyl trehalose was explored the oral acute toxicity, 28 days repeated dose toxicity and genotoxicity in Kunming mice. The Median Lethal Dose (LD50) of vanadyl trehalose was revealed to be 1000 mg/kg body weight in fasted Kunming mice. Stomach and intestine were demonstrated to be the main target organs of vanadyl trehalose through 28 days repeated dose toxicity study. And vanadyl trehalose also showed particular genotoxicity through mouse bone marrow micronucleus and mouse sperm malformation assay. In brief, vanadyl trehalose presented certain, but finite toxicity, which may provide experimental basis for the clinical application.

  7. Acute to chronic estimation of Daphnia magna toxicity within the QSAAR framework.

    PubMed

    Furuhama, A; Hayashi, T I; Tatarazako, N

    2016-10-21

    We constructed models for acute to chronic estimation of the Daphnia magna reproductive toxicities of chemical substances from their Daphnia magna acute immobilization toxicities. The models combined the acute toxicities with structural and physicochemical descriptors. We used multiregression analysis and selected the descriptors for the models by means of a genetic algorithm. Of the best 100 models (as indicated by the lack of fit score), 90% included the following descriptors: acute toxicity (i.e. an activity parameter), distribution coefficient (log D) and structural indicator variables that indicate the presence of -NH2 attached to aromatic carbon and the presence of a chlorine atom. We compared the predictive abilities of five of these quantitative structure-activity-activity relationship (QSAAR) acute to chronic estimation models with the predictive ability of a simple linear regression model. The comparison revealed that inclusion of structural and physicochemical descriptors such as those in QSAAR models can improve models for extrapolation from acute to chronic toxicity. Our results also provide a QSAAR framework that is expected to be useful for the further development of chronic toxicity estimation models.

  8. Effect of arbuscular mycorrhizal (G. etunicatum) fungus on antioxidant enzymes activity under zinc toxicity in lettuce plants.

    PubMed

    Farshian, Shadi; Khara, Jalil; Parviz, Malekzadeh

    2007-06-01

    Zinc is one of the eight trace elements which are essential for the normal healthy growth and reproduction of crop plants. Plants possess cellular mechanisms that may be involved in the detoxification of heavy metals and thus confer plants a better tolerance against them. Arbuscular mycorrhizal fungi colonization is one of these mechanisms. Here, the effect of mycorrhizal fungus G. etunicatum on Zn toxicity tolerance through enhanced activity of some of antioxidant enzymes has been studied. Treatments were applied in triplicates of two factorial analyses: (a) mycorrhizal and non-mycorrhizal; (b) 5 levels of Zinc (0, 1.5, 3.5, 5.5, 7.5 mM). Zinc was added to modified Hoagland's nutrient solution (with half P concentration). Plants were grown in growth chamber for 10 weeks. Toxicity symptoms such as necrosis and chlorosis appeared on the leaves. Activity of detoxifying enzymes Guaiacol peroxidase (GUPX) and Ascorbate peroxidase (APX) were measured. GPX activity in roots and shoots of mycorrhizal and non-mycorrhizal plants was increased. Also, APX activity increased in roots and shoots ofmycorrhizal and non-mycorrhizal plants. Root length colonization (RLC) was measured by gridline intersect method. Mycorrhizal colonization decreased due to Zinc exposure. The results indicate the probable role of arbuscular mycorrhizal colonization in stress tolerance.

  9. Effects of zinc against mercury toxicity in female rats 12 and 48 hours after HgCl2 exposure

    PubMed Central

    Mesquita, Mariana; Pedroso, Taíse F.; Oliveira, Cláudia S.; Oliveira, Vitor A.; do Santos, Rafael Francisco; Bizzi, Cezar Augusto; Pereira, Maria Ester

    2016-01-01

    This work investigated the toxicity of inorganic mercury and zinc preventive effects in female rats sacrificed 12 or 48 h after HgCl2 exposure. Female Wistar rats were subcutaneously injected with ZnCl2 (27 mg/kg) or saline (0.9 %), and 24 h later they were exposed to HgCl2 (5 mg/kg) or saline (0.9 %). Rats sacrificed 12 hours after Hg administration presented an increase in kidney weight and a decrease in renal ascorbic acid levels. Zinc pretreatment prevented the renal weight increase. Rats sacrificed 48 h after Hg exposure presented a decrease in body weight gain, an increase in renal weight, a decrease in renal δ-aminolevulinic acid dehydratase activity, an increase in serum creatinine and urea levels, and a decrease in kidney total thiol levels. Zinc pretreatment partly prevented the decrease in body weight gain and increase in creatinine levels, in addition to totally preventing renal δ-aminolevulinic acid dehydratase inhibition. Mercury accumulation in the kidney and liver in both periods was observed after Hg administration. These results show the different Hg effects along the time of intoxication, and a considerably preventive effect of zinc against Hg toxicity. PMID:27330529

  10. Evaluation of Pulmonary Toxicity of Zinc Oxide Nanoparticles Following Inhalation and Intratracheal Instillation

    PubMed Central

    Morimoto, Yasuo; Izumi, Hiroto; Yoshiura, Yukiko; Tomonaga, Taisuke; Oyabu, Takako; Myojo, Toshihiko; Kawai, Kazuaki; Yatera, Kazuhiro; Shimada, Manabu; Kubo, Masaru; Yamamoto, Kazuhiro; Kitajima, Shinichi; Kuroda, Etsushi; Kawaguchi, Kenji; Sasaki, Takeshi

    2016-01-01

    We conducted inhalation and intratracheal instillation studies of zinc oxide (ZnO) nanoparticles in order to examine their pulmonary toxicity. F344 rats were received intratracheal instillation at 0.2 or 1 mg of ZnO nanoparticles with a primary diameter of 35 nm that were well-dispersed in distilled water. Cell analysis and chemokines in bronchoalveolar lavage fluid (BALF) were analyzed at three days, one week, one month, three months, and six months after the instillation. As the inhalation study, rats were exposed to a concentration of inhaled ZnO nanoparticles (2 and 10 mg/m3) for four weeks (6 h/day, 5 days/week). The same endpoints as in the intratracheal instillation study were analyzed at three days, one month, and three months after the end of the exposure. In the intratracheal instillation study, both the 0.2 and the 1.0 mg ZnO groups had a transient increase in the total cell and neutrophil count in the BALF and in the expression of cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-2, chemokine for neutrophil, and heme oxygenase-1 (HO-1), an oxidative stress marker, in the BALF. In the inhalation study, transient increases in total cell and neutrophil count, CINC-1,-2 and HO-1 in the BALF were observed in the high concentration groups. Neither of the studies of ZnO nanoparticles showed persistent inflammation in the rat lung, suggesting that well-dispersed ZnO nanoparticles have low toxicity. PMID:27490535

  11. Influence of sulfate, Ca, and Mg on the acute toxicity of potassium dichromate to Daphnia similis

    SciTech Connect

    Hosokawa, Mamoru; Kuroda, Koichi ); Endo, Ginji; Horiguchi, Shunichi )

    1991-03-01

    In the Daphnia test which is commonly employed for assessing effects of chemicals to aquatic environments, it is well known that the toxicity of chemicals is variable with test animals and also with the chemistry of test waters. However, it is not clear what constituents in water affect toxicity of chemicals. The authors report here experimental results which show that sulfate, calcium and magnesium, commonly contained in aquatic environments, decrease the toxicity of K{sub 2}Cr{sub 2}O{sub 7} which is recommended as a reference toxicant in the acute toxicity test.

  12. Qsars for photoinduced toxicity: 1. acute lethality of polycyclic aromatic hydrocarbons to daphnia magna'

    SciTech Connect

    Mekenyan, O.G.; Ankley, G.T.; Veith, G.D.; Call, D.J.

    1994-01-01

    Research with a variety of aquatic species has shown that while polycyclic aromatic hydrocarbons (PAHs) are generally not acutely toxic in conventional laboratory tests, many are extremely toxic in the presence of sunlight. In an effort to develop a model for predicting which PAHs may exhibit photo-induced toxicity, Newsted and Giesy (1987) reported a parabolic relationship between the toxicity and the energy of the triplet state of a variety of PAHs. The authors have reexamined these data and propose a more mechanistic explanation for the prediction of photo-induced PAH toxicity. They sought a molecular descriptor which could be computed from structure rather than measured empirically.

  13. Evaluation of 2-week repeated oral dose toxicity of 100 nm zinc oxide nanoparticles in rats

    PubMed Central

    Ko, Je-Won; Hong, Eun-Taek; Lee, In-Chul; Park, Sung-Hyeuk; Park, Jong-Il; Seong, Nak-Won; Hong, Jeong-Sup; Yun, Hyo-In

    2015-01-01

    The aim of this study was to verify subacute oral dose toxicity of positively charged 100 nm zinc oxide (ZnOAE100[+]) nanoparticles (NPs) in Sprague-Dawley rats. ZnOAE100[+] NPs were administered to rats of each sex by gavage at 0, 500, 1,000, and 2,000 mg/kg/day for 14 days. During the study period, clinical signs, mortality, body weight, food consumption, hematology, serum biochemistry, gross pathology, organ weight, and histopathology were examined. Increased mortality and clinical signs, decreased body weight, feed consumption, hemoglobin (HB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), platelet (PT), and lymphocyte (LYM) and increased white blood cells (WBCs), neutrophils (NEUs), alkaline phosphatase (ALP), and histopathological alterations in the spleen, stomach, and pancreas were observed at 2,000 mg/kg/day. Increased clinical signs, decreased body weight, feed consumption, HB, HCT, MCV, MCH, MCHC, and LYM and increased WBCs, NEUs, ALP, and histopathological alterations in the spleen, stomach, and pancreas were seen at 1,000 mg/kg/day. Increased clinical signs, decreased MCV and MCH and increased histopathological alterations in the stomach and pancreas were found at 500 mg/kg/day. These results suggest that the target organs were the spleen, stomach, and pancreas in rats. The no-observed-adverse-effect level was <500 mg/kg for both sexes. PMID:26472967

  14. Zinc Phosphide Poisoning

    PubMed Central

    Doğan, Erdal; Güzel, Abdulmenap; Çiftçi, Taner; Aycan, İlker; Çetin, Bedri; Kavak, Gönül Ölmez

    2014-01-01

    Zinc phosphide has been used widely as a rodenticide. Upon ingestion, it gets converted to phosphine gas in the body, which is subsequently absorbed into the bloodstream through the stomach and the intestines and gets captured by the liver and the lungs. Phosphine gas produces various metabolic and nonmetabolic toxic effects. Clinical symptoms are circulatory collapse, hypotension, shock symptoms, myocarditis, pericarditis, acute pulmonary edema, and congestive heart failure. In this case presentation, we aim to present the intensive care process and treatment resistance of a patient who ingested zinc phosphide for suicide purposes. PMID:25101186

  15. Acute Electrocardiographic ST Segment Elevation May Predict Hypotension in a Swine Model of Severe Cyanide Toxicity

    DTIC Science & Technology

    2012-04-21

    induced shock, 30 swine were anesthetized and monitored and then intoxicated with a continuous cyanide infusion until severe hypotension (50 % of...TOXICOLOGY INVESTIGATION Acute Electrocardiographic ST Segment ElevationMay Predict Hypotension in a Swine Model of Severe Cyanide Toxicity Tylan A...Toxicology 2012 Abstract Cyanide causes severe cardiac toxicity resulting in tachycardia, hypotension, and cardiac arrest; however, the clinical diagnosis can

  16. Toxic Epidermal Necrolysis and Acute Kidney Injury due to Glyphosate Ingestion

    PubMed Central

    Indirakshi, J.; Sunnesh, A.; Aruna, M.; Reddy, M. Hari Krishna; Kumar, Anil C. V.; Chandra, V. Sarat; Sangeetha, B.; Katyarmal, D. T.; Ram, R.; Kumar, V. Siva

    2017-01-01

    The literature, particularly from India, is scarce on the renal effects of glyphosate poisoning. Glyphosate causes toxicity not only after its ingestion but also after dermal exposure by inhalation route and on eye exposure. We present a patient report of glyphosate consumption which resulted in toxic epidermal necrolysis – the first report after glyphosate consumption and acute kidney injury.

  17. Staphylococcal toxic shock syndrome presenting as acute respiratory distress and cor pulmonale.

    PubMed

    Zaki, S A; Shanbag, P; Chavan, V; Shenoy, P

    2010-01-01

    We describe a 7-year-old boy with staphylococcal toxic shock syndrome who presented with acute respiratory distress and cor pulmonale. We wish to highlight this unusual presentation as the diagnosis of toxic shock syndrome depends chiefly on a high degree of clinical suspicion. Early diagnosis and prompt institution of appropriate therapy will significantly reduce morbidity and mortality.

  18. Acute management of autoimmune toxicity in cancer patients on immunotherapy: Common toxicities and the approach for the emergency physician.

    PubMed

    Lomax, Anna J; McNeil, Catriona

    2017-01-16

    When a patient receiving anti-cancer treatment presents acutely unwell, an understanding of associated side effects of their therapy is critical. This review will discuss the approach to patients receiving anti-cancer treatment with immunotherapy presenting with autoimmune toxicities in the emergency setting. These toxicities are commonly referred to as immune-related adverse events (irAE). IrAE might consist of, but are not limited to, dermatologic, gastrointestinal (diarrhoea, colitis), hepatic, endocrine (thyroid dysfunction, hypophysitis, adrenal crisis), renal, ocular and pulmonary toxicity. General principles of managing these irAE in the acute setting will be outlined. Steroid therapy is a critical component of the treatment algorithm, being administered at high doses and for prolonged periods to switch off immune over-activation. Prompt intervention might prevent multi-organ failure and fatality, and allow patients to remain on effective anti-cancer therapy.

  19. Assessing the acute hazards of zinc oxide nanomaterials to Lumbriculus variegatus.

    PubMed

    O'Rourke, Shona; Stone, Vicki; Stolpe, Björn; Fernandes, Teresa F

    2015-08-01

    These studies were undertaken in order to propose and test new methods for the assessment of the acute hazard of ZnO nanoparticles (NPs) to the sediment dwelling oligochaete worm Lumbriculus variegatus. In order to support the developing nanotechnology sector, comprehensive studies must be conducted to assess the toxicity of nanomaterials (NMs) using environmentally relevant organisms. An important part of such studies will entail characterising and understanding the physicochemical properties of these NMs. In this study NMs were characterised using a range of techniques, in order to assess agglomeration/aggregation and dissolution. Toxicology studies included a behavioural assay and the measurement of oxidative stress. When considering the toxicology results from all experiments using L. variegatus within this paper ZnO NPs (0-10 mg/l) were found to cause acute toxicity in terms of behavioural response, but not to cause acute oxidative stress in terms of glutathione (GSH) depletion. It was also concluded that the behavioural assay and the GSH assay were both suitable techniques for assessing the acute hazard of NMs to L. variegatus.

  20. [Probiotics, prebiotics and zinc in the therapy and prevention of acute infectious diarrhoea in children: state of the art].

    PubMed

    Salvatore, S; Luini, C; Arrigo, S; Salmaso, M; Morando, L; Nespoli, L; Vandenplas, Y

    2007-12-01

    Selected probiotics (mainly Lactobacilli, and particularly LGG, and Saccharomyces boulardii) have recently demonstrated a therapeutic efficacy in acute diarrhoea, if used in the early phase of infection and at high concentration. Further data are needed to clarify their effect for prevention and travellers' diarrhoea. The mechanisms of action of probiotics need to be fully elucidated but seem to include a complex interaction of epithelial, molecular, metabolic and immune responses. There is an increasing evidence that different micro-organisms show different properties and efficacy. An accurate identification and selection of the strains, the dose and the patients are thus crucial for a correct therapeutic approach. Prebiotics can modify the intestinal flora and interact with the immune system of the host against specific pathogens. However, clinical trials are currently limited and a beneficial effect of prebiotics in acute diarrhoea is still lacking. In developing countries zinc supplementation demonstrated a significant reduction of fecal excretion, duration, severity and persistency of diarrhoea. Moreover, zinc may improve immune status, intestinal permeability, epithelial and enzymatic functions, and transport of electrolytes. The use of zinc in addition to oral rehydration solution (ORS) could thus theoretically improve the treatment and reduce the complications of diarrhoea worldwide. However, in developed countries, no trial using zinc supplementation in patients with acute diarrhoea has been published yet and the cost-benefit ratio of zinc supplementation needs to be assessed.

  1. Acute toxicity of furazolidone on Artemia salina, Daphnia magna, and Culex pipiens molestus larvae

    SciTech Connect

    Macri, A.; Stazi, A.V.; Dojmi di Delupis, G.

    1988-10-01

    As a result of evidence of the ecotoxicity of nitrofurans, the acute toxicity of furazolidone was tested in vivo on two aquatic organisms, Artemia salina and Daphnia magna, which are both crustaceans. Toxicity studies were also performed on larvae of Culex pipiens molestus. Results indicated a significant toxicity of the compound on Culex pipiens and Daphnia magna, while Artemia salina proved to be the least sensitive.

  2. Synergistic effect of piperonyl butoxide on acute toxicity of pyrethrins to Hyalella azteca.

    PubMed

    Giddings, Jeffrey; Gagne, James; Sharp, Janice

    2016-08-01

    A series of acute toxicity tests with the amphipod Hyalella azteca was performed to quantify the synergistic effect of piperonyl butoxide (PBO) on pyrethrin toxicity. Concentrations of PBO <4 µg/L caused no toxicity enhancement, whereas toxicity increased with PBO concentrations between 4 µg/L and 15 µg/L. Additive toxicity calculations showed that true synergism accounted for an increase in pyrethrin toxicity (decrease in median lethal concentration) of 1.4-fold to 1.6-fold and varied only slightly between 4 µg/L and 15 µg/L PBO, whereas direct toxicity of PBO accounted for an additional increase in mixture toxicity (up to 3.2-fold) that was proportional to PBO concentration. The results can be used to assess the risk of measured or predicted co-occurring concentrations of PBO and pyrethrins in surface waters. Environ Toxicol Chem 2016;35:2111-2116. © 2016 SETAC.

  3. MOAtox: A comprehensive mode of action and acute aquatic toxicity database for predictive model development.

    PubMed

    Barron, M G; Lilavois, C R; Martin, T M

    2015-04-01

    The mode of toxic action (MOA) has been recognized as a key determinant of chemical toxicity and as an alternative to chemical class-based predictive toxicity modeling. However, the development of quantitative structure activity relationship (QSAR) and other models has been limited by the availability of comprehensive high quality MOA and toxicity databases. The current study developed a dataset of MOA assignments for 1213 chemicals that included a diversity of metals, pesticides, and other organic compounds that encompassed six broad and 31 specific MOAs. MOA assignments were made using a combination of high confidence approaches that included international consensus classifications, QSAR predictions, and weight of evidence professional judgment based on an assessment of structure and literature information. A toxicity database of 674 acute values linked to chemical MOA was developed for fish and invertebrates. Additionally, species-specific measured or high confidence estimated acute values were developed for the four aquatic species with the most reported toxicity values: rainbow trout (Oncorhynchus mykiss), fathead minnow (Pimephales promelas), bluegill (Lepomis macrochirus), and the cladoceran (Daphnia magna). Measured acute toxicity values met strict standardization and quality assurance requirements. Toxicity values for chemicals with missing species-specific data were estimated using established interspecies correlation models and procedures (Web-ICE; http://epa.gov/ceampubl/fchain/webice/), with the highest confidence values selected. The resulting dataset of MOA assignments and paired toxicity values are provided in spreadsheet format as a comprehensive standardized dataset available for predictive aquatic toxicology model development.

  4. Prostate Hypofractionated Radiation Therapy With Injection of Hyaluronic Acid: Acute Toxicities in a Phase 2 Study

    SciTech Connect

    Chapet, Olivier; Decullier, Evelyne; Bin, Sylvie; Faix, Antoine; Ruffion, Alain; Jalade, Patrice; Fenoglietto, Pascal; Udrescu, Corina; Enachescu, Ciprian; Azria, David

    2015-03-15

    Purpose: Hypofractionated radiation therapy (RT) in prostate cancer can be developed only if the risk of rectal toxicity is controlled. In a multicenter phase 2 trial, hypofractionated irradiation was combined with an injection of hyaluronic acid (HA) to preserve the rectal wall. Tolerance of the injection and acute toxicity rates are reported. Methods and Materials: The study was designed to assess late grade 2 toxicity rates. The results described here correspond to the secondary objectives. Acute toxicity was defined as occurring during RT or within 3 months after RT and graded according to the Common Terminology Criteria for Adverse Events version 4.0. HA tolerance was evaluated with a visual analog scale during the injection and 30 minutes after injection and then by use of the Common Terminology Criteria at each visit. Results: From 2010 to 2012, 36 patients with low-risk to intermediate-risk prostate cancer were included. The HA injection induced a mean pain score of 4.6/10 ± 2.3. Thirty minutes after the injection, 2 patients still reported pain (2/10 and 3/10), which persisted after the intervention. Thirty-three patients experienced at least 1 acute genitourinary toxicity and 20 patients at least 1 acute gastrointestinal toxicity. Grade 2 toxicities were reported for 19 patients with urinary obstruction, frequency, or both and for 1 patient with proctitis. No grade 3 or 4 toxicities were reported. At the 3-month visit, 4 patients described grade 2 obstruction or frequency, and no patients had any grade 2 gastrointestinal toxicities. Conclusions: The injection of HA makes it possible to deliver hypofractionated irradiation over 4 weeks with a dose per fraction of > 3 Gy, with limited acute rectal toxicity.

  5. Systemic Lupus Erythematosus, Radiotherapy, and the Risk of Acute and Chronic Toxicity: The Mayo Clinic Experience

    SciTech Connect

    Pinn, Melva E.; Gold, Douglas G. M.; Petersen, Ivy A.; Osborn, Thomas G.; Brown, Paul D.; Miller, Robert C.

    2008-06-01

    Purpose: To determine the acute and chronic toxic effects of radiotherapy in patients with systemic lupus erythematosus (SLE). Methods and Materials: Medical records of 21 consecutive patients with SLE, who had received 34 courses of external beam radiotherapy and one low-dose-rate prostate implant, were retrospectively reviewed. Patients with discoid lupus erythematosus were excluded. Results: Median survival was 2.3 years and median follow-up 5.6 years. Eight (42%) of 19 patients evaluable for acute toxicity during radiotherapy experienced acute toxicity of Grade 1 or greater, and 4 (21%) had acute toxicity of Grade 3 or greater. The 5- and 10-year incidence of chronic toxicity of Grade 1 or greater was 45% (95% confidence interval [CI], 22-72%) and 56% (95% CI, 28-81%), respectively. The 5- and 10-year incidence of chronic toxicity of Grade 3 or greater was 28% (95% CI, 18-60%) and 40% (95% CI, 16-72%), respectively. Univariate analysis showed that chronic toxicity of Grade 1 or greater correlated with SLE renal involvement (p < 0.006) and possibly with the presence of five or more American Rheumatism Association criteria (p < 0.053). Chronic toxicity of Grade 3 or greater correlated with an absence of photosensitivity (p < 0.02), absence of arthritis (p < 0.03), and presence of a malar rash (p < 0.04). Conclusions: The risk of acute and chronic toxicity in patients with SLE who received radiotherapy was moderate but was not prohibitive of the use of radiotherapy. Patients with more advanced SLE may be at increased risk for chronic toxicity.

  6. Acute and chronic toxicity of boron to a variety of freshwater organisms.

    PubMed

    Soucek, David J; Dickinson, Amy; Koch, Brian T

    2011-08-01

    Boron enters the aquatic environment from various sources, including weathering of borates, sewage effluents, coal combustion, use of cleaning compounds, and agrochemicals. The present study was designed to generate data on acute and chronic boron toxicity in support of an update of water quality standards in Illinois, USA. We examined the acute toxicity of boron to eight different freshwater organisms including a fish, an insect, two crustaceans, and four bivalve mollusks. To our knowledge, this is the first study to present data on the toxicity of boron to freshwater mollusks. We also sought to clarify whether hardness or pH affect boron toxicity to aquatic life, and to quantify chronic effect levels in two freshwater species. Sensitivity among the various species ranged widely, with the fathead minnow (Pimephales promelas) being the most sensitive. Neither pH nor hardness had a consistent effect on acute boron toxicity to two crustaceans (Ceriodaphnia dubia and Hyalella azteca), but we observed evidence that chloride reduces boron toxicity to H. azteca. The fathead minnow, while more acutely sensitive than the other species, had a lower acute to chronic ratio than did H. azteca, which had reduced reproduction at 13 mg/L. While we do not know the extent to which the eight tested species represent the range of sensitivities of native but untested species in Illinois, the current water quality standard for Illinois (1 mg/L) is conservative with regard to the native species tested thus far.

  7. Acute toxicity of pyraclostrobin and trifloxystrobin to Hyalella azteca.

    PubMed

    Morrison, Shane A; McMurry, Scott T; Smith, Loren M; Belden, Jason B

    2013-07-01

    Fungicide application rates on row crop agriculture have increased across the United States, and subsequently, contamination of adjacent wetlands can occur through spray drift or field runoff. To investigate fungicide toxicity, Hyalella azteca amphipods were exposed to 2 fungicide formulations, Headline and Stratego, and their active strobilurin ingredients, pyraclostrobin and trifloxystrobin. Water-only exposures resulted in similar median lethal concentration (LC50; 20-25 µg/L) values for formulations and strobilurin ingredients, suggesting that toxicity is due to strobilurin ingredients. These values were below concentrations that could occur following spray drift over embedded cropland wetlands. When fungicides were added to overlying water of sediment-water microcosms, toxicity was reduced by 500% for Headline and 160% for Stratego, compared with water-only exposures, based on the total amount of fungicide added to the systems. In addition, when fungicides were added to sediment prior to the addition of water, the reduction in toxicity was even greater, with no toxicity occurring at environmentally relevant levels. Differences in toxicity among exposure groups were explained by dissipation from water as toxicity values based on measured water concentrations were within 20% between all systems. The present study reinforces previous studies that Headline and Stratego are toxic to nontarget aquatic organisms. However, the presence of sediment is likely to ameliorate some toxicity of fungicide formulations, especially if spraying occurs prior to wetland inundation.

  8. Comparative acute toxicity of a synthetic mine effluent to Ceriodaphnia dubia, larval fathead minnow and the freshwater mussel Anodonta imbecilis

    SciTech Connect

    Masnado, R.G.; Geis, S.W.; Sonzogni, W.C.

    1995-11-01

    To determine if water quality-based effluent limitations recommended for a proposed discharger would provide adequate protection of aquatic life, site-specific acute toxicity tests were performed. The proposed discharger studied was a mine to be located in northern Wisconsin. The mine`s discharge would flow into the Flambeau River, a relatively pristine river that harbors endangered freshwater mussels. The toxicity effects of synthetic effluents, representing a mixture of five different metals under contrasting conditions of hardness, were tested on several different organisms. Results indicated that Ceriodaphnia dubia exhibited a much greater sensitivity to various mixtures of cadmium, hexavalent chromium, copper, nickel, and zinc than did either larval fathead minnows (Pimephales promelas) or the freshwater mussel Anodonta imbecilis. Mixture o metals at the permitted discharge levels of individual metals were also found to be consistently toxic to C. dubia. Because C. dubia was found to be much more sensitive than A. imbecilis, an effluent safe for C. dubia should also be safe for A. imbecilis and the physiologically similar endangered mussels found in the river. Based on such testing, aquatic life toxicity-testing conditions and criteria suggested for the National Pollution Discharge Elimination System (NPDES) permit should be protective of C. dubia and, hence, other aquatic life such as endangered mussels. Overall, effluent limitations for proposed dischargers need to be based on the combined effect of complex effluents. Aquatic toxicity testing using synthetic effluents that approximate the expected discharge characteristics provides a viable approach to determining the limits for proposed dischargers of multiple pollutants.

  9. Prediction and experimental validation of acute toxicity of beta-blockers in Ceriodaphnia dubia.

    PubMed

    Fraysse, Benoit; Garric, Jeanne

    2005-10-01

    Acute toxicity of beta-adrenoceptor blockers (beta-blockers) was studied with beta-blockers as single compounds or in mixture using the standardized acute 2-d Ceriodaphnia dubia immobility test. The tested compounds were selected according to their selectivity for the beta1-adrenoceptor, with three beta1-selective blockers (acebutolol, atenolol, and metoprolol) and three non-beta1-selective blockers (nadolol, oxprenolol, and propranolol). The acute toxicity (median effective concentration) of the six single compounds ranged from 1.4 mg/L for propranolol to 163 mg/L for nadolol. According to European Union directive 93/67EEC, these values range from toxic for aquatic organisms to nonclassified. The more toxic compounds, propranolol and oxprenolol, are both characterized by a membrane-stabilizing activity, a strong affinity for the beta1-adrenoceptor, and a high octanol-water partition coefficient (log Kow). The property of beta-receptor selectivity seems not to be involved in the observed acute toxicity of the single compounds for C. dubia. Nevertheless, the toxicity of the selected compounds in mixture can be defined according to the beta1-selectivity. Two main joint effects have been detected: An independent action for the beta1-selective blockers, and an additive effect when either the nonselective beta1-selective blockers or the six compounds are tested together. The concentration addition model seems to be appropriate, providing a reasonable worst-case estimation of beta-blocker mixture toxicity for regulatory purposes.

  10. Toxic and nontoxic components of botulinum neurotoxin complex are evolved from a common ancestral zinc protein

    SciTech Connect

    Inui, Ken; Sagane, Yoshimasa; Miyata, Keita; Miyashita, Shin-Ichiro; Suzuki, Tomonori; Shikamori, Yasuyuki; Ohyama, Tohru; Niwa, Koichi; Watanabe, Toshihiro

    2012-03-16

    Highlights: Black-Right-Pointing-Pointer BoNT and NTNHA proteins share a similar protein architecture. Black-Right-Pointing-Pointer NTNHA and BoNT were both identified as zinc-binding proteins. Black-Right-Pointing-Pointer NTNHA does not have a classical HEXXH zinc-coordinating motif similar to that found in all serotypes of BoNT. Black-Right-Pointing-Pointer Homology modeling implied probable key residues involved in zinc coordination. -- Abstract: Zinc atoms play an essential role in a number of enzymes. Botulinum neurotoxin (BoNT), the most potent toxin known in nature, is a zinc-dependent endopeptidase. Here we identify the nontoxic nonhemagglutinin (NTNHA), one of the BoNT-complex constituents, as a zinc-binding protein, along with BoNT. A protein structure classification database search indicated that BoNT and NTNHA share a similar domain architecture, comprising a zinc-dependent metalloproteinase-like, BoNT coiled-coil motif and concanavalin A-like domains. Inductively coupled plasma-mass spectrometry analysis demonstrated that every single NTNHA molecule contains a single zinc atom. This is the first demonstration of a zinc atom in this protein, as far as we know. However, the NTNHA molecule does not possess any known zinc-coordinating motif, whereas all BoNT serotypes possess the classical HEXXH motif. Homology modeling of the NTNHA structure implied that a consensus K-C-L-I-K-X{sub 35}-D sequence common among all NTNHA serotype molecules appears to coordinate a single zinc atom. These findings lead us to propose that NTNHA and BoNT may have evolved distinct functional specializations following their branching out from a common ancestral zinc protein.

  11. Copper-zinc coergisms and metal toxicity at predefined ratio concentrations: Predictions based on synergistic ratio model.

    PubMed

    Obinna Obiakor, Maximilian; Damian Ezeonyejiaku, Chigozie

    2015-07-01

    A significant number of studies have centred on the single actions of heavy metals against test animals in predicting aquatic toxicity. However, practical existence of environmental toxicants is in multiple mixtures and variable undefined ratio combinatorial concentrations. Pollution abatement approaches in setting representative safe boundaries for metal contaminants is crucial with factual data on predictively modelled exposures of organisms to multiple mixtures. In continuance of our approach to toxicity of individual heavy metals, we determined the toxicity of binary mixtures of copper and zinc at predetermined ratios against tilapia species and also evaluated the coergisms based on synergistic ratio model for effective formulations of safe limits. Orecohromis niloticus species were exposed to copper and zinc (Cu:Zn) at ratios of 1:1 and 1:2 on 96hLC₅₀ index and mortality response analysed following the probit-log-dose regression with metal-metal interactions effectively modelled. The 96hLC₅₀ values for Cu:Zn were calculated to be 68.898 and 51.197 mg/l for ratios 1:1 and 1:2, respectively. The joint action toxicity of the metal mixtures was observed to differ from the metals acting singly against the same animal species. Synergistic coergisms were realized in most of the ratio mixtures except the antagonistic effect displayed by the combination of Cu:Zn in the ratio 1:1 when compared to the single action of copper. Biological toxicity of heavy metals however still appears uncertain, and consideration of multiple mixtures and interactions of toxicants in natural milieu is very crucial in environmental management of the existing and emerging contaminating metals.

  12. Three dimensional quantitative structure-toxicity relationship modeling and prediction of acute toxicity for organic contaminants to algae.

    PubMed

    Jin, Xiangqin; Jin, Minghao; Sheng, Lianxi

    2014-08-01

    Although numerous chemicals have been identified to have significant toxicological effect on aquatic organisms, there is still lack of a reliable, high-throughput approach to evaluate, screen and monitor the presence of organic contaminants in aquatic system. In the current study, we proposed a synthetic pipeline to automatically model and predict the acute toxicity of chemicals to algae. In the procedure, a new alignment-free three dimensional (3D) structure characterization method was described and, with this method, several 3D-quantitative structure-toxicity relationship (3D-QSTR) models were developed, from which two were found to exhibit strong internal fitting ability and high external predictive power. The best model was established by Gaussian process (GP), which was further employed to perform extrapolation on a random compound library consisting of 1014 virtually generated substituted benzenes. It was found that (i) substitution number can only exert slight influence on chemical׳s toxicity, but low-substituted benzenes seem to have higher toxicity than those of high-substituted entities, and (ii) benzenes substituted by nitro group and halogens exhibit high acute toxicity as compared to other substituents such as methyl and carboxyl groups. Subsequently, several promising candidates suggested by computational prediction were assayed by using a standard algal growth inhibition test. Consequently, four substituted benzenes, namely 2,3-dinitrophenol, 2-chloro-4-nitroaniline, 1,2,3-trinitrobenzene and 3-bromophenol, were determined to have high acute toxicity to Scenedesmus obliquus, with their EC50 values of 2.5±0.8, 10.5±2.1, 1.4±0.2 and 42.7±5.4μmol/L, respectively.

  13. Zinc oxide nanoparticles: a 90-day repeated-dose dermal toxicity study in rats

    PubMed Central

    Ryu, Hwa Jung; Seo, Mu Yeb; Jung, Sung Kyu; Maeng, Eun Ho; Lee, Seung-Young; Jang, Dong-Hyouk; Lee, Taek-Jin; Jo, Ki-Yeon; Kim, Yu-Ri; Cho, Kyu-Bong; Kim, Meyoung-Kon; Lee, Beom Jun; Son, Sang Wook

    2014-01-01

    Zinc oxide (ZnO) works as a long-lasting, broad-spectrum physical sunblock, and can prevent skin cancer, sunburn, and photoaging. Nanosized ZnO particles are used often in sunscreens due to consumer preference over larger sizes, which appear opaque when dermally applied. Although the US Food and Drug Administration approved the use of nanoparticles (NPs) in sunscreens in 1999, there are ongoing safety concerns. The aim of this study was to evaluate the subchronic toxicity of ZnO NPs after dermal application according to the Organization for Economic Cooperation and Development Test Guidelines 411 using Good Laboratory Practice. Sprague Dawley rats were randomly divided into eight (one control, one vehicle control, three experimental, and three recovery) groups. Different concentrations of ZnO NPs were dermally applied to the rats in the experimental groups for 90 days. Clinical observations as well as weight and food consumption were measured and recorded daily. Hematology and biochemistry parameters were determined. Gross pathologic and histopathologic examinations were performed on selected tissues from all animals. Analyses of tissue were undertaken to determine target organ tissue distribution. There was no increased mortality in the experimental group. Although there was dose-dependent irritation at the site of application, there were no abnormal findings related to ZnO NPs in other organs. Increased concentrations of ZnO in the liver, small intestine, large intestine, and feces were thought to result from oral ingestion of ZnO NPs via licking. Penetration of ZnO NPs through the skin seemed to be limited via the dermal route. This study demonstrates that there was no observed adverse effect of ZnO NPs up to 1,000 mg/kg body weight when they are applied dermally. PMID:25565832

  14. Comparative population growth of Ceriodaphnia dubia and Daphnia pulex (Cladocera) exposed to zinc toxicity.

    PubMed

    Sanchez-Ortiz, Jonathan Raul; Sarma, S S S; Nandini, S

    2010-01-01

    Population growth of two cladocerans (Ceriodaphnia dubia and Daphnia pulex) exposed to 4 different concentrations of ZnCl(2) (0.125, 0.25, 0.5 and 1.0 mg L(-1), plus controls) at one algal food (Scenedesmus acutus) density (0.5 X 10(6) cells mL(-1)) was quantified for 30 days. Population densities of C. dubia and D. pulex decreased with increasing concentration of Zn in the medium. At a concentration of 1 mg L(-1) of ZnCl(2), both C. dubia and D. pulex did not reproduce and died within a week. The peak population densities of C. dubia ranged from 0.2 to 6.0 ind. mL(-1), depending on the Zn level in the medium, whereas this range was lower for D. pulex (0.2 to 4.1 ind. mL(-1)). The peak population density was inversely related to the Zn concentration. The rate of population increase (r) varied from -0.12 to +0.14 and -0.02 to +0.23 per day for C. dubia and D. pulex, respectively, depending on the Zn level in the medium. Statistically, both the peak population density and the r were significantly affected by the heavy metal concentration in the medium. Multiple comparison tests showed that the rate of population increase (r) of D. pulex in the lowest ZnCl(2) level (0.125 mg L(-1)) was significantly higher than controls. However, under similar conditions, the r of C. dubia was significantly lower than controls. With a further increase in Zn level, the growth rates of both the cladoceran species were significantly reduced as compared to controls. The results are discussed in relation to published data on the toxicity of zinc to freshwater zooplankton.

  15. A case of life-threatening acute kidney injury with toxic encephalopathy caused by Dioscorea quinqueloba.

    PubMed

    Kang, Kyung-Sik; Heo, Sang Taek

    2015-01-01

    Some herbal medications induce acute kidney injury. The acute kidney injuries caused by herbal medications are mild and commonly treated by palliative care. A 51-years-old man who drank the juice squeezed from the raw tubers of Dioscorea quinqueloba (D. quinqueloba) was admitted with nausea, vomiting and chilling. He developed a seizure with decreased level of consciousness. He was diagnosed with acute kidney injury, which was cured by continuous venovenous hemodialfiltration. Non-detoxified D. quinqueloba can cause severe acute kidney injury with toxic encephalopathy. It is critical to inform possible adverse effects of the medicinal herbs and to implement more strict regulation of these products.

  16. Toxicity profiling of water contextual zinc oxide, silver, and titanium dioxide nanoparticles in human oral and gastrointestinal cell systems.

    PubMed

    Giovanni, Marcella; Tay, Chor Yong; Setyawati, Magdiel Inggrid; Xie, Jianping; Ong, Choon Nam; Fan, Rongli; Yue, Junqi; Zhang, Lifeng; Leong, David Tai

    2015-12-01

    Engineered nanoparticles (ENPs) are increasingly detected in water supply due to environmental release of ENPs as the by-products contained within the effluent of domestic and industrial run-off. The partial recycling of water laden with ENPs, albeit at ultra-low concentrations, may pose an uncharacterized threat to human health. In this study, we investigated the toxicity of three prevalent ENPs: zinc oxide, silver, and titanium dioxide over a wide range of concentrations that encompasses drinking water-relevant concentrations, to cellular systems representing oral and gastrointestinal tissues. Based on published in silico-predicted water-relevant ENPs concentration range from 100 pg/L to 100 µg/L, we detected no cytotoxicity to all the cellular systems. Significant cytotoxicity due to the NPs set in around 100 mg/L with decreasing extent of toxicity from zinc oxide to silver to titanium dioxide NPs. We also found that noncytotoxic zinc oxide NPs level of 10 mg/L could elevate the intracellular oxidative stress. The threshold concentrations of NPs that induced cytotoxic effect are at least two to five orders of magnitude higher than the permissible concentrations of the respective metals and metal oxides in drinking water. Based on these findings, the current estimated levels of NPs in potable water pose little cytotoxic threat to the human oral and gastrointestinal systems within our experimental boundaries.

  17. Alternative approaches for identifying acute systemic toxicity: Moving from research to regulatory testing.

    PubMed

    Hamm, Jon; Sullivan, Kristie; Clippinger, Amy J; Strickland, Judy; Bell, Shannon; Bhhatarai, Barun; Blaauboer, Bas; Casey, Warren; Dorman, David; Forsby, Anna; Garcia-Reyero, Natàlia; Gehen, Sean; Graepel, Rabea; Hotchkiss, Jon; Lowit, Anna; Matheson, Joanna; Reaves, Elissa; Scarano, Louis; Sprankle, Catherine; Tunkel, Jay; Wilson, Dan; Xia, Menghang; Zhu, Hao; Allen, David

    2017-01-06

    Acute systemic toxicity testing provides the basis for hazard labeling and risk management of chemicals. A number of international efforts have been directed at identifying non-animal alternatives for in vivo acute systemic toxicity tests. A September 2015 workshop, Alternative Approaches for Identifying Acute Systemic Toxicity: Moving from Research to Regulatory Testing, reviewed the state-of-the-science of non-animal alternatives for this testing and explored ways to facilitate implementation of alternatives. Workshop attendees included representatives from international regulatory agencies, academia, nongovernmental organizations, and industry. Resources identified as necessary for meaningful progress in implementing alternatives included compiling and making available high-quality reference data, training on use and interpretation of in vitro and in silico approaches, and global harmonization of testing requirements. Attendees particularly noted the need to characterize variability in reference data to evaluate new approaches. They also noted the importance of understanding the mechanisms of acute toxicity, which could be facilitated by the development of adverse outcome pathways. Workshop breakout groups explored different approaches to reducing or replacing animal use for acute toxicity testing, with each group crafting a roadmap and strategy to accomplish near-term progress. The workshop steering committee has organized efforts to implement the recommendations of the workshop participants.

  18. Lipid rafts: linking prion protein to zinc transport and amyloid-β toxicity in Alzheimer's disease

    PubMed Central

    Watt, Nicole T.; Griffiths, Heledd H.; Hooper, Nigel M.

    2014-01-01

    Dysregulation of neuronal zinc homeostasis plays a major role in many processes related to brain aging and neurodegenerative diseases, including Alzheimer's disease (AD). Yet, despite the critical role of zinc in neuronal function, the cellular mechanisms underpinning its homeostatic control are far from clear. We reported that the cellular prion protein (PrPC) is involved in the uptake of zinc into neurons. This PrPC-mediated zinc influx required the metal-binding octapeptide repeats in PrPC and the presence of the zinc permeable AMPA channel with which PrPC directly interacted. Together with the observation that PrPC is evolutionarily related to the ZIP family of zinc transporters, these studies indicate that PrPC plays a key role in neuronal zinc homeostasis. Therefore, PrPC could contribute to cognitive health and protect against age-related zinc dyshomeostasis but PrPC has also been identified as a receptor for amyloid-β oligomers which accumulate in the brains of those with AD. We propose that the different roles that PrPC has are due to its interaction with different ligands and/or co-receptors in lipid raft-based signaling/transport complexes. PMID:25364748

  19. Comparison of methods for evaluating acute and chronic toxicity in marine sediments.

    PubMed

    Greenstein, Darrin; Bay, Steven; Anderson, Brian; Chandler, G Thomas; Farrar, J Daniel; Keppler, Charles; Phillips, Bryn; Ringwood, Amy; Young, Diana

    2008-04-01

    Sublethal test methods are being used with increasing frequency to measure sediment toxicity, but little is known about the relative sensitivity of these tests compared to the more commonly used acute tests. The present study was conducted to compare the sensitivity of several acute and sublethal methods and to investigate their correlations with sediment chemistry and benthic community condition. Six sublethal methods (amphipod: Leptocheirus plumulosus survival, growth, and reproduction; polychaete: Neanthes arenaceodentata survival and growth; benthic copepod: Amphiascus tenuiremis life cycle; seed clam: Mercenaria mercenaria growth; oyster: Crassostrea virginica lysosome destabilization; and sediment-water interface testing with mussel embryos, Mytilus galloprovincialis) and two acute methods (amphipod survival with Eohaustorius estuarius and L. plumulosus) were used to test split sediment samples from stations in California. The test with Amphiascus proved to be the most sensitive sublethal test and the most sensitive overall, identifying 90% of the stations as toxic. The Leptocheirus 10-d test was the most sensitive of the acute tests, identifying 60% of the stations as toxic. In general, the sublethal tests were not more sensitive to sediments than the acute tests, with the sublethal tests finding an average of 35% of the stations to be toxic while the acute found 44%. Of the sublethal tests, only the Amphiascus endpoints and Neanthes growth significantly (p toxicity endpoints and the indicators of benthic community condition. Differences in test characteristics such as mode of exposure, species-specific contaminant sensitivity, changes in contaminant bioavailability, and influence of noncontaminant stressors on the benthos may have been responsible for variation in response among the tests and low correspondence with benthic community condition. The

  20. A preliminary report on zinc-induced resistance to nitrogen mustard toxicity in mice

    SciTech Connect

    Shackelford, M.E.; Tobey, R.A.

    1988-12-01

    Previous studies with cultured human normal fibroblasts indicated that treatment of cells with zinc before exposure to alkylating agents enhanced cell survival by seven- to nine-fold. To establish whether a similar zinc-induced protective response could be elicited in vivo, a set of preliminary experiments was carried out in which Balb/cJ mice were treated with zinc chloride (2 mg/kg body weight) or saline by intraperitoneal (ip) injection at 48, 36, 24, and 12 h before ip administration of 4 mg/kg of the alkylating agent nitrogen mustard. Of the animals that received saline before nitrogen mustard, 57% were killed compared with only 20% in the group treated with zinc before administration of the alkylating agent. These results (which almost certainly were achieved with less than optimal induction conditions) provide evidence for the existence, in vivo, of a zinc-inducible process that reduces alkylating agent lethality. 12 refs., 4 figs.

  1. 40 CFR 799.9110 - TSCA acute oral toxicity.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... of Prevention, Pesticides, and Toxic Substances (OPPTS) harmonized test guideline 870.1100 (August... of test substance per unit weight of test animal (milligrams per kilogram). (d) Alternative.... EPA will accept three alternative Organization for Economic Cooperation and Development (OECD)...

  2. 40 CFR 799.9110 - TSCA acute oral toxicity.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... of Prevention, Pesticides, and Toxic Substances (OPPTS) harmonized test guideline 870.1100 (August... of test substance per unit weight of test animal (milligrams per kilogram). (d) Alternative.... EPA will accept three alternative Organization for Economic Cooperation and Development (OECD)...

  3. 40 CFR 799.9110 - TSCA acute oral toxicity.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... of Prevention, Pesticides, and Toxic Substances (OPPTS) harmonized test guideline 870.1100 (August... of test substance per unit weight of test animal (milligrams per kilogram). (d) Alternative.... EPA will accept three alternative Organization for Economic Cooperation and Development (OECD)...

  4. 40 CFR 799.9110 - TSCA acute oral toxicity.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... of Prevention, Pesticides, and Toxic Substances (OPPTS) harmonized test guideline 870.1100 (August... of test substance per unit weight of test animal (milligrams per kilogram). (d) Alternative.... EPA will accept three alternative Organization for Economic Cooperation and Development (OECD)...

  5. 40 CFR 799.9110 - TSCA acute oral toxicity.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... of Prevention, Pesticides, and Toxic Substances (OPPTS) harmonized test guideline 870.1100 (August... of test substance per unit weight of test animal (milligrams per kilogram). (d) Alternative.... EPA will accept three alternative Organization for Economic Cooperation and Development (OECD)...

  6. Acute and Subacute Oral Toxicity of Periodate in Rats

    DTIC Science & Technology

    2014-11-17

    sodium periodate via oral gavage resulted in a cascade of effects that were secondary to kidney toxicity. Decreased mass of ovaries and epididymides and...testicular degeneration were observed in sodium periodate groups with signs of kidney toxicity. These groups also exhibited decreased T3 and T4 in the...presence of decreased TSH, a pattern associated with uremia. Sodium periodate exposed rats exhibited both activation of the innate immune system and

  7. PRN 2001-2: Acute Toxicity Data Requirements For Granular Pesticide Products, Including Those With Granular Fertilizers in the Product.

    EPA Pesticide Factsheets

    This PR Notice announces guidance intended to streamline the acute toxicity review and classification process for certain granular pesticide products, including those products that contain granular fertilizers.

  8. Mitigation of malathion's acute toxicity by four submersed macrophyte species.

    PubMed

    Brogan, William R; Relyea, Rick A

    2013-07-01

    Some submersed macrophyte species rapidly sorb some insecticides from the water, potentially reducing exposure for aquatic species. The rates at which macrophytes remove insecticides, however, can differ widely among plant species. Furthermore, few studies have examined how much macrophytes actually influence insecticide toxicity to sensitive animals. The authors quantified the ability of several macrophyte species to mitigate insecticide toxicity by comparing the survival of the aquatic herbivore, Daphnia magna, following exposure to a factorial combination of 3 malathion concentrations (0 µg/L, 3 µg/L, and 24 µg/L) and 7 macrophyte treatments (no macrophytes, 4 different macrophyte monocultures, and 2 inert substrates: plastic plants and polypropylene rope). The authors also quantified the rate that different macrophytes reduced malathion's toxicity by exposing D. magna to water samples collected from each treatment after 2 h, 8 h, and 48 h of exposure. The results revealed that whereas 3 µg/L and 24 µg/L of malathion decimated D. magna in the no-macrophyte, plastic plant, and rope treatments, all 4 macrophyte species strongly mitigated these effects. When the authors compared the rate at which malathion's toxicity decreased, they found that all macrophytes negated malathion's toxicity within 2 h, whereas it took more than 8 h in the absence of macrophytes or in the presence of inert substrates. These results demonstrate that numerous macrophyte species can equally and strongly mitigate insecticide toxicity, whereas inert substrates cannot.

  9. Toxicity of TNT Wastewaters to Aquatic Organisms. Volume 1. Acute Toxicity of LAP Wastewater and 2,4,6-Trinitrotoluene

    DTIC Science & Technology

    1983-03-01

    used to assess the adequacy of current pollution abatement technologies and thus influence research and development in this area. This report...wastewater samples, was defined as a 1.6-to-I mixture o! TNT and RDX. "The results of flow-through acute toxicity terzs with the inverte - brate Daphniamagna...The "unadjusted" confidence interval for the LCSO is derived by inverting the likelihood ratio test for determining whether any specified

  10. Investigations in Fish Control: 92. Acute and Chronic Toxicity of Rotenone to Daphnia magna, 93. Toxicity of Rotenone to Developing Rainbow Trout, 94. Oral Toxicity of Rotenone to Mammals.

    DTIC Science & Technology

    1988-01-01

    completed as part of the EPA requirements. One of the studies required consisted of acute and chronic toxicity tests on Daphnia magna , the organism chosen because it is sensitive to toxic substances.

  11. Acute toxicity and effects analysis of endosulfan sulfate to freshwater fish species.

    PubMed

    Carriger, John F; Hoang, Tham C; Rand, Gary M; Gardinali, Piero R; Castro, Joffre

    2011-02-01

    Endosulfan sulfate is a persistent environmental metabolite of endosulfan, an organochlorine insecticide-acaricide presently registered by the United States Environmental Protection Agency. There is, however, limited acute fish toxicity data for endosulfan sulfate. This study determines the acute toxicity (LC₅₀s and LC₁₀s) of endosulfan sulfate to three inland Florida native fish species (mosquitofish [Gambusia affinis]; least killifish [Heterandria formosa]; and sailfin mollies [Poecilia latipinna]) as well as fathead minnows (Pimephales promelas). Ninety-six-h acute toxicity tests were conducted with each fish species under flow-through conditions. For all of the above-mentioned fish species, 96-h LC₅₀ estimates ranged from 2.1 to 3.5 μg/L endosulfan sulfate. The 96-h LC₁₀ estimates ranged from 0.8 to 2.1 μg/L endosulfan sulfate. Of all of the fish tested, the least killifish appeared to be the most sensitive to endosulfan sulfate exposure. The above-mentioned data were combined with previous acute toxicity data for endosulfan sulfate and freshwater fish for an effects analysis. The effects analysis estimated hazardous concentrations expected to exceed 5, 10, and 50% of the fish species' acute LC₅₀ or LC₁₀ values (HC₅, HC₁₀, and HC₅₀). The endosulfan sulfate freshwater-fish acute tests were also compared with the available freshwater-fish acute toxicity data for technical endosulfan. Technical endosulfan is a mixture of α- and β-endosulfan. The LC₅₀s had a wider range for technical endosulfan, and their distribution produced a lower HC₁₀ than for endosulfan sulfate. The number of freshwater-fish LC₅₀s for endosulfan sulfate is much smaller than the number available for technical endosulfan, reflecting priorities in examining the toxicity of the parent compounds of pesticides. The toxicity test results and effects analyses provided acute effect values for endosulfan sulfate and freshwater fish that might be applied

  12. Acute toxicity of Headline® fungicide to Blanchard's cricket frogs (Acris blanchardi).

    PubMed

    Cusaac, J Patrick W; Morrison, Shane A; Belden, Jason B; Smith, Loren M; McMurry, Scott T

    2016-04-01

    Previous laboratory studies have suggested that pyraclostrobin-containing fungicide formulations are toxic to amphibians at environmentally relevant concentrations. However, it is unknown if all pyraclostrobin formulations have similar toxicity and if toxicity occurs in different amphibian species. We investigated the acute toxicity of two formulations, Headline(®) fungicide and Headline AMP(®) fungicide, to Blanchard's cricket frogs (Acris blanchardi) based on a direct overspray scenario. In addition, we examined body residues of fungicide active ingredients in A. blanchardi following direct exposure to Headline AMP fungicide. Headline fungicide and Headline AMP fungicide had similar toxicity to A. blanchardi with calculated median lethal doses of 2.1 and 1.7 µg pyraclostrobin/cm(2), respectively, which are similar to the suggested maximum label rate in North American corn (2.2 and 1.52 µg pyraclostrobin/cm(2), respectively). Tissue concentrations of pyraclostrobin were lower than predicted based on full uptake of a direct dose, and did not drop during the first 24 h after exposure. Headline fungicides at corn application rates are acutely toxic to cricket frogs, but acute toxicity in the field will depend on worst-case exposure.

  13. Sensitivity of Danio rerio (Teleostei, Cyprinidae) during two stages of development based on acute toxicity tests.

    PubMed

    Freiry, R; Stelzer, J A A; Maltchik, L; Arenzon, A

    2014-10-01

    The sensitivity of Danio rerio to three chemicals was compared at two growth stages [larval (10 ± 2 after hatching) and post-larval (60 ± 4 days after hatching)] based on acute toxicity tests. Thirty-nine 48 h acute toxicity tests were performed with the substances CuSO4, NaCl and KCl. The 48 h LC50 values at the two growth stages were compared by independent samples t-tests. The results showed a clear decrease in sensitivity when post-larval organisms were used. Since acute toxicity test methods for D. rerio that recommend using post-larval stage fish do not represent the most sensitive stage of the test organism, our study suggests a revision of the methods to use larval fish.

  14. Acute and Subchronic Toxicity of Inhaled Toluene in Male ...

    EPA Pesticide Factsheets

    The effects of exposure to volatile organic compounds (VOCs), which are of concern to the EPA, are poorly understood, in part because of insufficient characterization of how human exposure duration impacts VOC effects. Two inhalation studies with multiple endpoints, one acute and one subchronic, were conducted to seek effects of the VOC, toluene, in rats and to compare the effects between acute and subchronic exposures. Adult male Long-Evans rats were exposed to toluene vapor (n = 6 per group) at a concentration of 0 or l 019 ± 14 ppm for 6 h in the acute study and at 0 ± 0, 10 ± 1.4, 97 ± 7, or 995 ± 43 ppm for 6 h/d, 5 d/week for 13 weeksin the subchronic study. For the acute study, brains were dissected on ice within 30 min of the end of exposure, while for the subchronic study, brains were dissected 18 h after the last exposure. Frontal cortex, hippocampus, cerebellum, and striatum were assayed for a variety of oxidative stress (OS) parameters including total aconitase (TA), protein carbonyls, glutathione peroxidase (GPX), glutathione reductase (GRD), glutathione transferase (GST), y-­glutamylcysteine synthetase (GCS), superoxide dismutase (SOD), total antioxidants (TAS), NADPH quinone oxidoreductase- 1 (NQO1 ), and NADH ubiquinone reductase (UBIQ-RD) activities using commercially available kits. Following acute exposure, UBIQ-RD, GCS and GRD were increased significantly only in the cerebellum, while TAS was increased in frontal cortex. On the other

  15. Testing an application of a biotic ligand model to predict acute toxicity of metal mixtures to rainbow trout.

    PubMed

    Iwasaki, Yuichi; Kamo, Masashi; Naito, Wataru

    2015-04-01

    The authors tested the applicability of a previously developed biotic ligand model (BLM) to predict acute toxicity of single metals and metal mixtures (cadmium, lead, and zinc) to rainbow trout fry (Oncorhynchus mykiss) from a single available dataset. The BLM used in the present study hypothesizes that metals inhibit an essential cation (calcium) and organisms die as a result of its deficiency, leading to an assumption that the proportion of metal-binding ligand (f) is responsible for the toxic effects of metals on the survival of rainbow trout. The f value is a function of free-ion concentrations of metals computed by a chemical speciation model, and the function has affinity constants as model parameters. First, the survival effects of single metals were statistically modeled separately (i.e., f-survival relationship) by using the generalized linear mixed model with binomial distribution. The modeled responses of survival rates to f overlapped reasonably irrespective of metals tested, supporting the theoretical prediction from the BLM that f-survival relationships are comparable regardless of metal species. The authors thus developed the generalized linear mixed model based on all data pooled across the single-metal tests. The best-fitted model well predicted the survival responses observed in mixture tests (r = 0.97), providing support for the applicability of the BLM to predict effects of metal mixtures.

  16. Ratios between acute aquatic toxicity and effects on population growth rates in relation to toxicant mode of action

    SciTech Connect

    Roex, E.W.M.; Gestel, C.A.M. Van; Wezel, A.P. Van; Straalen, N.M. Van

    2000-03-01

    Environmental risk assessment of chemicals is mostly based on the results of standardized toxicity tests. To obtain environmental quality criteria, extrapolation factors are used that depend on the amount and quality of available data. These extrapolation factors do not, however, take into account the mode of action of the compound tested or the life history of the test organism. In this study, the authors analyzed the variability in acute-to-chronic ratios (ACRs) for various chemicals in relation to their mode of action. Chemicals were classified as nonpolar narcotics, polar narcotics, specifically acting compounds, and heavy metals. As an acute endpoint, the LC50 was used; as a chronic endpoint, the lowest test concentration at which the natural rate of population increase (r) is affected, or LOEC(r), was used. Data were derived from the on-line literature. Nonpolar narcotic chemicals demonstrate the smallest variation in ACRs, and acute tests can be used to derive chronic endpoints for this class. For the other classes, the variation in ACRs is larger. Fish species especially show a relatively large ACR. For heavy metals, differences in the mode of action may play an important role in explaining differences in ACRs. For the other three classes, however, it is less reliable to predict chronic toxicity using the results of acute tests. In general, differences in species sensitivity rather than in mode of action for the chemical seem to determine differences in ACRs.

  17. Case of acute lead toxicity associated with Ayurvedic supplements.

    PubMed

    Breyre, Amelia; Green-McKenzie, Judith

    2016-06-30

    Use of traditional folkloric remedies not disclosed to the physician may be difficult to identify as a source of lead toxicity. This report illustrates the presentation of a 26-year-old man who, during his 1 month vacation in India, was treated for low back pain with Ayurvedic herbal medicine. On his return to the USA, he presented to the emergency department with epigastric pain, weight loss, dark stools, nausea and vomiting. He was admitted and noted to be anaemic with a blood lead level (BLL) of 94.8 µg/dL. Peripheral blood smear demonstrated basophilic stippling. Chelation therapy with succimer was initiated. The patient became asymptomatic within months. Three years later, he remained asymptomatic with BLL <20 µg/dL. Physicians should be cognisant of potential toxicity from these Ayurvedic medications and have a heightened level of suspicion for lead toxicity in the face of anaemia and abdominal pain without obvious cause.

  18. Inhibition effect of glyphosate on the acute and subacute toxicity of cadmium to earthworm Eisenia fetida.

    PubMed

    Zhou, Chui-Fan; Wang, Yu-Jun; Sun, Rui-Juan; Liu, Cun; Fan, Guang-Ping; Qin, Wen-Xiu; Li, Cheng-Cheng; Zhou, Dong-Mei

    2014-10-01

    The acute and subacute toxicities of cadmium (Cd) to earthworm Eisenia fetida in the presence and absence of glyphosate were studied. Although Cd is highly toxic to E. fetida, the presence of glyphosate markedly reduced the acute toxicity of Cd to earthworm; both the mortality rate of the earthworms and the accumulation of Cd decreased with the increase of the glyphosate/Cd molar ratio. The subcellular distribution of Cd in E. fetida tissues showed that internal Cd was dominant in the intact cells fraction and the heat-stable proteins fraction. The presence of glyphosate reduced the concentration of Cd in all fractions, especially the intact cells. During a longer period of exposure, the weight loss of earthworm and the total Cd absorption was alleviated by glyphosate. Thus, the herbicide glyphosate can reduce the toxicity and bioavailability of Cd in the soil ecosystems at both short- and long-term exposures.

  19. Role of surface modification in zinc oxide nanoparticles and its toxicity assessment toward human dermal fibroblast cells

    PubMed Central

    Ramasamy, Mohankandhasamy; Das, Minakshi; An, Seong Soo A; Yi, Dong Kee

    2014-01-01

    The wide-scale applications of zinc oxide (ZnO) nanoparticles (NPs) in photocatalysts, gas sensors, and cosmetics may cause toxicity to humans and environments. Therefore, the aim of the present study was to reduce the toxicity of ZnO NPs by coating them with a silica (SiO2) layer, which could be used in human applications, such as cosmetic preparations. The sol–gel method was used to synthesize core ZnO with SiO2-shelled NPs (SiO2/ZnO NPs) with varying degrees of coating. Diverse studies were performed to analyze the toxicity of NPs against cells in a dose- and time-dependent manner. To ensure the decreased toxicity of the produced SiO2/ZnO NPs, cytotoxicity in membrane damage and/or intracellular reactive oxygen species (ROS) were assessed by employing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, lactate dehydrogenase, 2′,7′-dichlorofluorescin, and lipid peroxide estimations. The cores of ZnO NPs exhibited cytotoxicity over time, regardless of shell thickness. Nevertheless, the thicker SiO2/ZnO NPs revealed reduced enzyme leakage, decreased peroxide production, and less oxidative stress than their bare ZnO NPs or thinner SiO2/ZnO NPs. Therefore, thicker SiO2/ZnO NPs moderated the toxicity of ZnO NPs by restricting free radical formation and the release of zinc ions, and decreasing surface contact with cells. PMID:25143723

  20. Acute and subchronic oral toxicities of Calendula officinalis extract in Wistar rats.

    PubMed

    Lagarto, Alicia; Bueno, Viviana; Guerra, Isbel; Valdés, Odalys; Vega, Yamile; Torres, Leonid

    2011-05-01

    We have studied the acute and subchronic oral toxicities of Calendula officinalis extract in male and female Wistar rats. A single acute C. officinalis extract dose of 2000 mg/kg dissolved in distilled water was administered by oral gavage for acute toxicity. Subchronic doses of 50, 250 and 1000 mg/kg/day were administered in drinking water. The major toxicological endpoints examined included animal body weight, water and food intake, selected tissue weights, and histopathological examinations. In addition, we examined blood elements: hematocrit, hemoglobin concentration, erythrocyte count, total and differential leukocyte count and blood clotting time and blood chemistry: glucose, total cholesterol, urea, total proteins, alkaline phosphatase, alanine aminotransferase (ALT) and aspartate aminotransferase (AST). In the acute study, there were no mortality and signs of toxicity. In the subchronic study, several of the blood elements were significantly affected in males and females after 90 days; hemoglobin, erythrocytes, leukocytes and blood clotting time. For blood chemistry parameters, ALT, AST and alkaline phosphatase were affected. Histopathological examination of tissues showed slight abnormalities in hepatic parenchyma that were consistent with biochemical variations observed. These studies indicate that the acute and subchronic toxicities of C. officinalis extract are low.

  1. Acute toxicity assessment of ANAMMOX substrates and antibiotics by luminescent bacteria test.

    PubMed

    Ding, Shuang; Wu, Junwei; Zhang, Meng; Lu, Huifeng; Mahmood, Qaisar; Zheng, Ping

    2015-12-01

    Acute toxicities of anaerobic ammonia oxidation (ANAMMOX) substrates and four antibiotics from pharmaceutical wastewaters on ANAMMOX process were reported. Individual and joint acute toxicity assays were performed using 50% inhibitory concentration (IC50). Results showed that IC50 values and their 95% confidence interval of ammonium chloride (A), sodium nitrite (B), penicillin G-Na (C), polymyxin B sulfate (D), chloramphenicol (E) and kanamycin sulfate (F) were 2708.9 (2247.9-3169.9), 1475.4 (1269.9-1680.9), 5114.4 (4946.4-5282.4), 10.2 (1.8-18.6), 409.9 (333.7-486.1) and 5254.1 (3934.4-6573.8) mgL(-1) respectively, suggesting toxicities were in the order of D>E>B>A>C>F. Joint acute toxicities of bicomponent mixtures A and B, C and D, C and F, D and F were independent; D and E, E and F were additive while C and E were synergistic. Joint acute toxicities of multicomponent mixtures were synergistic or additive. Luminescent bacteria test is an easy and robust method for forecasting the feasibility of ANAMMOX process for pharmaceutical wastewater treatment.

  2. Hypofractionated IMRT of the Prostate Bed After Radical Prostatectomy: Acute Toxicity in the PRIAMOS-1 Trial

    SciTech Connect

    Katayama, Sonja; Striecker, Thorbjoern; Kessel, Kerstin; Sterzing, Florian; Habl, Gregor; Edler, Lutz; Debus, Juergen; Herfarth, Klaus

    2014-11-15

    Purpose: Hypofractionated radiation therapy as primary treatment for prostate cancer is currently being investigated in large phase 3 trials. However, there are few data on postoperative hypofractionation. The Radiation therapy for the Prostate Bed With or Without the Pelvic Lymph Nodes (PRIAMOS 1) trial was initiated as a prospective phase 2 trial to assess treatment safety and toxicity of a hypofractionated intensity modulated radiation therapy (IMRT) of the prostate bed. Methods and Materials: From February to September 2012, 40 patients with indications for adjuvant or salvage radiation therapy were enrolled. One patient dropped out before treatment. Patients received 54 Gy in 18 fractions to the prostate bed with IMRT and daily image guidance. Gastrointestinal (GI) and genitourinary (GU) toxicities (according to National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0) were recorded weekly during treatment and 10 weeks after radiation therapy. Results: Overall acute toxicity was favorable, with no recorded adverse events grade ≥3. Acute GI toxicity rates were 56.4% (grade 1) and 17.9% (grade 2). Acute GU toxicity was recorded in 35.9% of patients (maximum grade 1). Urinary stress incontinence was not influenced by radiation therapy. The incidence of grade 1 urinary urge incontinence increased from 2.6% before to 23.1% 10 weeks after therapy, but grade 2 urge incontinence remained unchanged. Conclusions: Postoperative hypofractionated IMRT of the prostate bed is tolerated well, with no severe acute side effects.

  3. Acute Toxicity and Cytotoxicity of Pereskia aculeata, a Highly Nutritious Cactaceae Plant.

    PubMed

    Silva, Debora O; Seifert, Mauricio; Nora, Fabiana R; Bobrowski, Vera L; Freitag, Rogerio A; Kucera, Heidi R; Nora, Leonardo; Gaikwad, Nilesh W

    2017-04-01

    Pereskia aculeata is a Cactaceae plant with valuable nutritional properties, including terrific amounts of protein, minerals, vitamins, and fiber. However, P. aculeata is reported to contain antinutrients and alkaloids in its leaves. In addition, in a study on growth and development, Wistar rats fed with P. aculeata and casein as protein source grew less than the control group (fed with casein only). Therefore, in this study, we evaluated, for the first time, the oral acute toxicity of P. aculeata in rats and also the cytotoxicity behavior of the plant on lettuce seeds. The acute toxicity research was carried out using dried P. aculeata ethanolic extract, in three different doses, administered by gavage to 24 female Wistar rats. The rats were then examined for signs of toxicity, food intake, body weight, and fecal excretion fluctuations, as well as histopathological alterations, using eight different body tissues. The acute toxicity study did not show any difference among the groups in either clinical evaluation or histopathological analyses. For the cytotoxicity study, dried P. aculeata ethanolic extract was applied on lettuce seeds in five different concentrations. These seeds were evaluated for germination, root and shoot length, and mitotic index. The results show that P. aculeata extract affects lettuce root and shoot growth, but not germination or mitotic index. In conclusion, the acute toxicity on rats and the cytogenotoxicity on lettuce of P. aculeata are neglectable, validating the potential of this plant to be used as a functional food.

  4. Evaluation of the importance of astrocytes when screening for acute toxicity in neuronal cell systems.

    PubMed

    Woehrling, E K; Hill, E J; Coleman, M D

    2010-02-01

    Reliable, high throughput, in vitro preliminary screening batteries have the potential to greatly accelerate the rate at which regulatory neurotoxicity data is generated. This study evaluated the importance of astrocytes when predicting acute toxic potential using a neuronal screening battery of pure neuronal (NT2.N) and astrocytic (NT2.A) and integrated neuronal/astrocytic (NT2.N/A) cell systems derived from the human NT2.D1 cell line, using biochemical endpoints (mitochondrial membrane potential (MMP) depolarisation and ATP and GSH depletion). Following exposure for 72 h, the known acute human neurotoxicants trimethyltin-chloride, chloroquine and 6-hydroxydopamine were frequently capable of disrupting biochemical processes in all of the cell systems at non-cytotoxic concentrations. Astrocytes provide key metabolic and protective support to neurons during toxic challenge in vivo and generally the astrocyte containing cell systems showed increased tolerance to toxicant insult compared with the NT2.N mono-culture in vitro. Whilst there was no consistent relationship between MMP, ATP and GSH log IC(50) values for the NT2.N/A and NT2.A cell systems, these data did provide preliminary evidence of modulation of the acute neuronal toxic response by astrocytes. In conclusion, the suitability of NT2 neurons and astrocytes as cell systems for acute toxicity screening deserves further investigation.

  5. Towards global QSAR model building for acute toxicity: Munro database case study.

    PubMed

    Chavan, Swapnil; Nicholls, Ian A; Karlsson, Björn C G; Rosengren, Annika M; Ballabio, Davide; Consonni, Viviana; Todeschini, Roberto

    2014-10-09

    A series of 436 Munro database chemicals were studied with respect to their corresponding experimental LD50 values to investigate the possibility of establishing a global QSAR model for acute toxicity. Dragon molecular descriptors were used for the QSAR model development and genetic algorithms were used to select descriptors better correlated with toxicity data. Toxic values were discretized in a qualitative class on the basis of the Globally Harmonized Scheme: the 436 chemicals were divided into 3 classes based on their experimental LD50 values: highly toxic, intermediate toxic and low to non-toxic. The k-nearest neighbor (k-NN) classification method was calibrated on 25 molecular descriptors and gave a non-error rate (NER) equal to 0.66 and 0.57 for internal and external prediction sets, respectively. Even if the classification performances are not optimal, the subsequent analysis of the selected descriptors and their relationship with toxicity levels constitute a step towards the development of a global QSAR model for acute toxicity.

  6. Mortality, accumulation, and distribution of zinc in the gill system of the dogfish following zinc treatment

    SciTech Connect

    Crespo, S.; Blasch, J.

    1980-06-01

    Besides being an essential element, Zn has been shown to be toxic to aquatic organisms. Acute lethalities of Zn salts to teleosts have been reported, but few data regarding Zn toxicity to elasmobranchs can be found. To evaluate the effect of Zn on elasmobranchs and to compare the data with those on teleosts this paper studies Zn toxicity and the accumulation of the metal in the gills of the dogfish Scyliorhinus canicula exposed to 180 and 80 ppM of zinc.

  7. A two-generational reproductive toxicity study of zinc in rats.

    PubMed

    Khan, Abu T; Graham, Thomas C; Ogden, L; Ali, S; Salwa; Thompson, Sherylee J; Shireen, Kaniz F; Mahboob, Mohd

    2007-05-01

    A two-generation reproductive toxicity study of zinc chloride (ZnCl(2)) was conducted in rats. F(o) male and female rats were administered 0.00 (control), 7.50 (low), 15.00 (mid) and 30.00 (high) mg/kg/day of ZnCl(2). Selected F(1) male and female rats were exposed to the same doses received by their parents (F(o)). Exposure of F(0) parental rats to ZnCl(2) showed significant reduction in fertility, viability (days 0 and 4), and the body weight of F(1) pups from the high-dose group but caused no effects on litter size, weaning index, and sex ratio. Similarly, the continued exposure of F(1) parental rats to ZnCl(2) also reduced fertility, liter size, viability (day 0), and the body weight of F(2) pups within the high-dose group but caused no effects on weaning index and sex ratio. Exposure of ZnCl(2) to F(0) and F(1) parental males resulted in a significant reduction in their body weights, and the F(0) and F(1) parental females did not show any significant difference in their body weights compared to their control groups. However, the postpartum dam weights of both F(0) and F(1) female rats were significantly reduced compared to their controls. Exposure of ZnCl(2) to F(o) and F(1) generation parental rats did not produce any significant change of their clinical signs as well as their clinical pathology parameters, except the alkaline phosphotase (ALK) level, which showed an upward trend in both sexes of both generations. Exposure of ZnCl(2) to F(0) rats resulted in a reduction of brain, liver, kidney, spleen and seminal vesicles weights of males and in the spleen and uterus of females. Similarly, exposure of F(1) rats to ZnCl(2) also resulted in reduction of brain, liver, kidney, adrenal, spleen, prostate and seminal vesicles weights of males and in spleen and uterus of females. ZnCl(2) exposure resulted in grossly observed gastro-intestianla (GI) tract, lymphoreticular/hematopoietic, and reproductive tract lesions in parental rats in both generations. Reduced body

  8. In vitro cytotoxicity testing for prediction of acute human toxicity.

    PubMed

    Barile, F A; Dierickx, P J; Kristen, U

    1994-06-01

    This study was designed to compare the cytotoxic concentrations of chemicals, determined with three independent in vitro cytotoxicity testing protocols, with each other and with established animal LD50 values, and against human toxic concentrations for the same chemicals. Ultimately, these comparisons allow us to evaluate the potential of in vitro cell culture methods for the ability to screen a variety of chemicals for prediction of human toxicity. Each laboratory independently tested 50 chemicals with known human lethal plasma concentrations and LD50 values. Two of the methods used monolayer cell cultures to measure the incorporation of radiolabeled amino acids into newly synthesized proteins and cellular protein content, while the third technique used the pollen tube growth test. The latter is based on the photometric quantification of pollen tube mass production in suspension culture. Experiments were performed in the absence or presence of increasing doses of the test chemical, during an 18- to 24-h incubation. Inhibitory concentrations were extrapolated from concentration-effect curves after linear regression analysis. Comparison of the cytotoxic concentrations confirms previous independent findings that the experimental IC50 values are more accurate predictors of human toxicity than equivalent toxic blood concentrations (HETC values) derived from rodent LD50s. In addition, there were no conclusive statistical differences among the methods. It is anticipated that, together, these procedures can be used as a battery of tests to supplement or replace currently used animal protocols for human risk assessment.

  9. Acute toxicity of pesticides in adult and weanling rats.

    PubMed

    Gaines, T B; Linder, R E

    1986-08-01

    LD50 values were determined for 57 pesticides administered by the oral or dermal route to adult male and female Sherman rats. Thirty-six of the chemicals were also tested by the oral route in one sex of weanlings. Nine pesticides tested by the oral route (bufencarb, cacodylic acid, dialifor, deltamethrin, dicamba, diquat, quintozene, phoxim, pyrazon) and four tested by the dermal route (bufencarb, chlordimeform, dichlofenthion, leptophos) were more toxic to females than to males whereas famphur and 2,4,5-T (oral route) were less toxic to females. Eighteen of the test chemicals were more toxic to the adult than to the weanling and four compounds (leptophos, methidathion, pyrazon, and sulfoxide) were more toxic to the weanling. In additional studies the variability of the LD50 value over a 1-year period was examined for two typical insecticides. Six consecutive bimonthly oral LD50 determinations for parathion and DDT in adults of both sexes indicated that the LD50 values were little affected by the time of year that the tests were done.

  10. Draft Test Guideline: Oyster Acute Toxicity Test (Shell Deposition)

    EPA Pesticide Factsheets

    The following draft test guideline is part of a series of test guidelines that have been developed by EPA for use in the testing of pesticides and toxic substances, and the development of test data for submission to the Agency for review.

  11. Draft Test Guideline: Fish Acute Toxicity Test, Freshwater And Marine

    EPA Pesticide Factsheets

    The following draft test guideline is part of a series of test guidelines that have been developed by EPA for use in the testing of pesticides and toxic substances, and the development of test data for submission to the Agency for review.

  12. Draft Test Guideline: Bivalve Acute Toxicity Test (Embryo Larval)

    EPA Pesticide Factsheets

    The following draft test guideline is part of a series of test guidelines that have been developed by EPA for use in the testing of pesticides and toxic substances, and the development of test data for submission to the Agency for review.

  13. Draft Test Guideline: Whole Sediment Acute Toxicity Invertebrates, Marine

    EPA Pesticide Factsheets

    The following draft test guideline is part of a series of test guidelines that have been developed by EPA for use in the testing of pesticides and toxic substances, and the development of test data for submission to the Agency for review.

  14. Draft Test Guideline: Aquatic Invetebrate Acute Toxicity, Test, Freshwater Daphnids

    EPA Pesticide Factsheets

    The following draft test guideline is part of a series of test guidelines that have been developed by EPA for use in the testing of pesticides and toxic substances, and the development of test data for submission to the Agency for review.

  15. Draft Test Guideline: Fish Acute Toxicity Mitigated By Humic Acid

    EPA Pesticide Factsheets

    The following draft test guideline is part of a series of test guidelines that have been developed by EPA for use in the testing of pesticides and toxic substances, and the development of test data for submission to the Agency for review.

  16. Draft Test Guideline: Whole Sediment Acute Toxicity Invertebrates, Freshwater

    EPA Pesticide Factsheets

    The following draft test guideline is part of a series of test guidelines that have been developed by EPA for use in the testing of pesticides and toxic substances, and the development of test data for submission to the Agency for review.

  17. Chronic cadmium toxicity to sperm of heavy cigarette smokers: immunomodulation by zinc.

    PubMed

    Al-Bader, A; Omu, A E; Dashti, H

    1999-01-01

    The aim of the study was to investigate the role of zinc therapy in 125 male cigarette smokers with infertility. The mechanism involved in the zinc/cadmium relationship was evaluated through the effect of a zinc-deficient diet and supplementation on testes of male adult Sprague-Drew rats. Heavy smoking was associated with low sperm count, motility, and morphology and increased seminal cadmium levels. Zinc therapy improved sperm quality and increased seminal IL-4, but reduced TNF-alpha and IFN-gamma. A zinc-deficient diet led to high cadmium testicular accumulation comparable with those supplemented with cadmium. Cadmium had a linear correlation with TNF-alpha and IFN-gamma, but not with IL-4. Cytology of testicular aspirate and histopathology were normal in supplemented groups as in controls. These results indicate that zinc modulates the putative effect of cadmium through its enhancement of T-helper 2 cytokines expression and down-regulation of T-helper 1 cytokines.

  18. Zinc toxicity among galvanization workers in the iron and steel industry.

    PubMed

    El Safty, Amal; El Mahgoub, Khalid; Helal, Sawsan; Abdel Maksoud, Neveen

    2008-10-01

    Galvanization is the process of coating steel or cast iron pieces with zinc, allowing complete protection against corrosion. The ultimate goal of this work was to assess the effect of occupational exposure to zinc in the galvanization process on different metals in the human body and to detect the association between zinc exposure and its effect on the respiratory system. This study was conducted in 111 subjects in one of the major companies in the iron and steel industry. There were 61 subjects (workers) who were involved in the galvanization process. Fifty adult men were chosen as a matched reference group from other departments of the company. All workers were interviewed using a special questionnaire on occupational history and chest diseases. Ventilatory functions and chest X rays were assessed in all examined workers. Also, complete blood counts were performed, and serum zinc, iron, copper, calcium, and magnesium levels were tested. This study illustrated the relation between zinc exposure in the galvanization process and high zinc levels among exposed workers, which was associated with a high prevalence rate of metal fume fever (MFF) and low blood copper and calcium levels. There was no statistically significant difference between the exposed and control groups with regards to the magnesium level. No long-term effect of metals exposure was detected on ventilatory functions or chest X rays among the exposed workers.

  19. Support Vector Machine (SVM) as Alternative Tool to Assign Acute Aquatic Toxicity Warning Labels to Chemicals.

    PubMed

    Michielan, Lisa; Pireddu, Luca; Floris, Matteo; Moro, Stefano

    2010-01-12

    Quantitative structure-activity relationship (QSAR) analysis has been frequently utilized as a computational tool for the prediction of several eco-toxicological parameters including the acute aquatic toxicity. In the present study, we describe a novel integrated strategy to describe the acute aquatic toxicity through the combination of both toxicokinetic and toxicodynamic behaviors of chemicals. In particular, a robust classification model (TOXclass) has been derived by combining Support Vector Machine (SVM) analysis with three classes of toxicokinetic-like molecular descriptors: the autocorrelation molecular electrostatic potential (autoMEP) vectors, Sterimol topological descriptors and logP(o/w) property values. TOXclass model is able to assign chemicals to different levels of acute aquatic toxicity, providing an appropriate answer to the new regulatory requirements. Moreover, we have extended the above mentioned toxicokinetic-like descriptor set with a more toxicodynamic-like descriptors, as for example HOMO and LUMO energies, to generate a valuable SVM classifier (MOAclass) for the prediction of the mode of action (MOA) of toxic chemicals. As preliminary validation of our approach, the toxicokinetic (TOXclass) and the toxicodynamic (MOAclass) models have been applied in series to inspect both aquatic toxicity hazard and mode of action of 296 chemical substances with unknown or uncertain toxicodynamic information to assess the potential ecological risk and the toxic mechanism.

  20. Acute toxicity of diphacinone in Northern bobwhite: Effects on survival and blood clotting

    USGS Publications Warehouse

    Rattner, Barnett A.; Horak, Katherine E.; Warner, Sarah E.; Johnston, John J.

    2010-01-01

    The anticoagulant rodenticide diphacinone was slightly toxic (acute oral LD50 2014 mg/kg) to Northern bobwhite (Colinus virginianus) in a 14-day acute toxicity trial. Precise and sensitive assays of blood clotting (prothrombin time, Russell?s Viper venom time, and thrombin clotting time) were adapted for use in quail, and this combination of assays is recommended to measure the effects of anticoagulant rodenticides. A single oral sublethal dose of diphacinone (434 mg/kg body weight) prolonged clotting time at 48 h post-dose compared to controls. At 783 mg/kg (approximate LD02), clotting time was prolonged at both 24 and 48 h post-dose. Prolongation of in vitro clotting time reflects impaired coagulation complex activity, and was detected before overt signs of toxicity were apparent at the greatest dosages (2868 and 3666 mg/kg) in the acute toxicity trial. These clotting time assays and toxicity data will assist in the development of a pharmacodynamic model to predict toxicity, and also facilitate rodenticide hazard and risk assessments in avian species.

  1. Acute toxicity, mutagenicity, and estrogenicity of bisphenol-A and other bisphenols.

    PubMed

    Chen, Min-Yu; Ike, Michihiko; Fujita, Masanori

    2002-02-01

    Although abundant data are available on the toxicity of bisphenol-A (2,2-bis (4-hydroxydiphenyl)propane; BPA), little is known about the toxicities of the structurally similar compounds, namely bisphenols (BPs). A variety of BPs were examined for their acute toxicity against Daphnia magna, mutagenicity, and estrogenic activity using the Daphtoxkit (Creasel Ltd.), the umu test system, and the yeast two-hybrid system, respectively, in comparison with BPA. BPA was moderately toxic to D. magna (48-h EC50 was 10 mg/l) according to the current U.S. EPA acute toxicity evaluation standard, and it was weakly estrogenic with 5 orders of magnitude lower activity than that of the natural estrogen 17 beta-estradiol in the yeast screen, while no mutagenicity was observed. All seven BPs tested here showed moderate to slight acute toxicity, no mutagenicity, and weak estrogenic activity as well as BPA. Some of the BPs showed considerably higher estrogenic activity than BPA, and others exhibited much lower activity. Among the tested BPs, two compounds, i.e., bisphenol-S (bis(4-hydroxydiphenyl)sulfone) and bis(4-hydroxyphenyl)sulfide, have never been reported for their estrogenic activity previously.

  2. Dispersant and salinity effects on weathering and acute toxicity of South Louisiana crude oil.

    PubMed

    Kuhl, Adam J; Nyman, J Andrew; Kaller, Michael D; Green, Christopher C

    2013-11-01

    Chemical dispersants are an important technology in the remediation of oil spills in the aquatic environment, facilitating degradation of crude oil and salinity is an important factor in dispersant effectiveness. The aim of the present study was to explore the role of salinity on the degradation chemistry of crude oil polycyclic aromatic hydrocarbons (PAHs) and acute toxicity of the water accommodated fraction (WAF) of the dispersant COREXIT 9500A and chemically dispersed crude oil on a common estuarine fish. Laboratory microcosms were designed at salinities of 4 parts per thousand (ppt), 12 ppt, or 18 ppt and spiked with crude oil, COREXIT 9500A, or a combined exposure to crude oil and COREXIT and allowed to biodegrade for 1 wk, 4 wk, and 16 wk. The WAF was harvested for analytical PAH analysis and acute toxicity testing in juvenile Fundulus grandis. Compared with undispersed oil, COREXIT exponentially increased the PAH concentrations in the WAF for up to 16 wk; hopane-normalized concentrations indicated that biodegradation was slowed for the first 4 wk. Dispersed crude oil and COREXIT were acutely toxic following 1 wk of biodegradation with no correlation between PAH concentrations and crude oil WAF mortality. Both dispersant and dispersant oil mixtures remained toxic for at least 4 wk at the lowest salinity tested, suggesting increased sensitivity or reduced biodegradation of toxic components in low-saline environments. At the lowest salinity, oil dispersed with COREXIT was more toxic than either the COREXIT alone or oil alone, even after 16 wk of biodegradation.

  3. Acute and subchronic toxicity of naturally weathered Exxon Valdez crude oil in mallards and ferrets

    SciTech Connect

    Stubblefield, W.A.; Hancock, G.A.; Ford, W.H.; Ringer, R.K.

    1995-11-01

    The toxic properties of naturally weathered Exxon Valdez crude oil (WEVC) were assessed in a battery of acute and subchronic toxicity tests using mallards, Anas platyrhynchos, and European ferrets, Mustela putorius. Adult mallard acute oral toxicity study results indicated no mortalities or signs o toxicity, i.e., no-observed-adverse-effect level (NOAEL) and median lethal dose (LD50) > 5,000 mg/kg. Acute oral feeding and food avoidance tests with ducklings also indicated no toxicity (NOAEL and LC50 > 50,000 mg/kg diet) with no evidence of food avoidance (FAC50 > 20,000 mg/kg diet). No mortalities or toxic signs were noted in a 14-d feeding study with adult birds at dietary concentrations up to 100,000 mg WEVC/kg diet. Among clinical and physiological end points evaluated, the only significant difference noted was an increase in liver: body weight ratios in the 100,000-mg WEVC/kg diet dose group. No differences in clinical chemistry or hematological parameters were noted, and there were no consistent differences in histological evaluations of organ tissues. Daily oral doses of up to 5,000 mg/kg of WEVC over 5 d resulted in minimal effects on ferrets. Increased serum albumin concentrations were observed in the 5,000-mg/kg dose group females and decreased spleen weights were noted in females of all WEVC treatment groups. No other significant observations were noted.

  4. Acute toxicity during external-beam radiotherapy for localized prostate cancer: Comparison of different techniques

    SciTech Connect

    Vijayakumar, S.; Awan, A.; Karrison, T.; Culbert, H.; Chan, S.; Kolker, J.; Low, N.; Halpern, H.; Rubin, S.; Chen, G.T.Y.; Weicheselbaum, R.R. )

    1993-01-15

    The chronic and acute toxicities associated with conventional radiotherapy of localized prostate cancer are well documented. However, the degree and incidence of toxicities with conformal techniques are not known. Studying side effects associated with modern radiotherapeutic techniques is more important now since there has been a general trend to use computerized tomography-based techniques in recent years; beam's eye view-based conformal techniques are also becoming more commonplace. It is possible that the local disease control can be improved with the delivery of higher doses than currently used. Conformation of the treatment volume to the target volume may facilitate such dose-escalation. However, prior to such dose-escalation, it is important to know the toxicities associated with such techniques with conventional doses. We have compared week-by-week acute toxicities associated with conventional (Group A, 16 patients), computerized tomography-based, manual (Group B, 57 patients) and beam's eye view-based (Group C, 43 patients) techniques during 7 weeks of radiotherapy. Group B and C patients were treated contemporaneously (1988-1990). The incidence of acute toxicities was significantly less with the beams eye view-based technique than with the other two methods. A trend suggesting increased severity of toxicity with increase in the volume of treatment was seen.

  5. Acute toxicological impact of nano- and submicro-scaled zinc oxide powder on healthy adult mice

    NASA Astrophysics Data System (ADS)

    Wang, Bing; Feng, Weiyue; Wang, Meng; Wang, Tiancheng; Gu, Yiqun; Zhu, Motao; Ouyang, Hong; Shi, Junwen; Zhang, Fang; Zhao, Yuliang; Chai, Zhifang; Wang, Haifang; Wang, Jing

    2008-02-01

    In this work, the acute oral toxicity of 20- and 120-nm ZnO powder at doses of 1-, 2-, 3-, 4-, 5-g/kg body weight was evaluated referred to the OECD guidelines for testing of chemicals. As the results, both 20- and 120-nm ZnO belong to non-toxic chemicals according to the Globally Harmonized Classification System (GHS) for the classification of chemicals. The distribution determination showed that Zn was mainly retained in the bone, kidney and pancreas after 20- and 120-nm ZnO administration. However, the results of blood measurement suggest that the increase in blood viscosity could be induced by low and median dose of 20-nm ZnO but high dose of 120-nm ZnO. The pathological examination showed that the 120-nm ZnO treated mice had dose-effect pathological damages in stomach, liver, heart and spleen, whereas, 20-nm ZnO displayed negative dose-effect damages in liver, spleen and pancreas. Therefore, we conclude that the liver, spleen, heart, pancreas and bone are the target organs for 20- and 120-nm ZnO oral exposure. More attention should be paid on the potential toxicity induced by low dose of 20-nm ZnO oral exposure.

  6. Acute toxicity bioassays of mercuric chloride and malathion on air-breathing fish Channa punctatus (Bloch).

    PubMed

    Pandey, Sanjay; Kumar, Ravindra; Sharma, Shilpi; Nagpure, N S; Srivastava, Satish K; Verma, M S

    2005-05-01

    Acute toxicity tests (96 h) were conducted in flow-through systems to determine the lethal toxicity of a heavy metal compound, mercuric chloride, and an organophosphorus pesticide, malathion, to air-breathing teleost fish, Channa punctatus (Bloch) and to study their behavior. The 96-h LC50 values were determined, as well as safe levels. The results indicate that mercuric chloride is more toxic than malathion to the fish species under study. Dose- and dose-time-dependent increases in mortality rate were also observed in response to both test chemicals.

  7. SYSTEMIC IMBALANCE OF ESSENTIAL METALS AND CARDIAC GENE EXPRESSION IN RATS FOLLOWING ACUTE PULMONARY ZINC EXPOSURE

    EPA Science Inventory

    We have recently demonstrated that PM containing water-soluble zinc may cause cardiac injury following pulmonary exposure. To investigate if pulmonary zinc exposure causes systemic metal imbalance and direct cardiac effects, we intratracheally (IT) instilled male Wistar Kyoto (WK...

  8. Acute tellurium toxicity from ingestion of metal-oxidizing solutions.

    PubMed

    Yarema, Mark C; Curry, Steven C

    2005-08-01

    Tellurium is an element used in the vulcanization of rubber and in metal-oxidizing solutions to blacken or tarnish metals. Descriptions of human toxicity from tellurium ingestion are rare. We report the clinical course of 2 children who ingested metal-oxidizing solutions containing substantial concentrations of tellurium. Clinical features included vomiting, black discoloration of the oral mucosa, and a garlic odor to the breath. One patient developed corrosive injury to the esophagus secondary to the high concentration of hydrochloric acid in the solution. Both patients recovered without serious sequelae, which is typical of tellurium toxicity. An awareness of situations in which children may be exposed to tellurium and its clinical presentation may assist clinicians in the diagnosis of this rare poisoning.

  9. Acute Toxicity of Sodium Fluorescein to Ashy Pebblesnails Fluminicola fuscus

    USGS Publications Warehouse

    Stockton, Kelly A.; Moffitt, Christine M.; Blew, David L.; Farmer, C. Neil

    2011-01-01

    Water resource agencies and groundwater scientists use fluorescein dyes to trace ground water flows that supply surface waters that may contain threatened or endangered mollusk species. Since little is known of the toxicity of sodium fluorescein to mollusks, we tested the toxicity of sodium fluorescein to the ashy pebblesnail Fluminicola fuscus. The pebblesnail was selected as a surrogate test species for the threatened Bliss Rapid snail Taylorcocha serpenticola that is endemic to the Snake River and its tributaries in the Hagerman Valley, Idaho. In laboratory tests, we expose replicated groups of snails to a series of concentrations of fluorescein in a static 24 h exposure at 15 degrees C. Following the exposure, we removed snails, rinsed them, and allowed a 48 h recovery in clean water before recording mortality. We estimated 377 mg/L as the median lethal dose. Mortality to snails occurred at concentrations well above those expected in test wells during the monitoring efforts.

  10. Determination of acute toxicity of polychlorinated biphenyls to photobactrium phosphoreum

    SciTech Connect

    Chu, S.; Xu, X.; He, Y.

    1997-02-01

    Polychlorinated biphenyls (PCBs) are a highly lipophilic group of global pollutants, consisting of 209 congeners. PCBs were discovered before the turn of the century and their usefulness for industry, because of their physical properties, was recognized early. The distribution of PCBs in the environment was not noticed until Jensen and his colleagues found PCBs in wildlife samples. Since then, investigations in many parts of the world have revealed the widespread distribution of PCBs in environmental samples and PCVs are persistent and accumulate in food webs. Thus, determination of toxicities of commercial PCB mixtures and PCB congeners are required. Toxicity tests using luminous bacteria have shown high correlation to traditional bioassays. This study compared the EC50 values of the commercial mixtures, PCB3 and PCB5, with those of Aroclor 1242 and Aroclor 1254. 12 refs., 2 tabs.

  11. Physiology is pivotal for interactions between salinity and acute copper toxicity to fish and invertebrates.

    PubMed

    Grosell, M; Blanchard, J; Brix, K V; Gerdes, R

    2007-08-30

    The present paper presents original data and a review of the copper (Cu) toxicity literature for estuarine and marine environments. For the first time, acute Cu toxicity across the full salinity range was determined. Killifish, Fundulus heteroclitus, eggs were hatched in freshwater (FW), 2.5, 5, 10, 15, 22 and 35 ppt (seawater, SW) and juveniles were allowed to acclimate for 7 days prior to acute toxicity testing. Sensitivity was highest in FW (96 h LC50: 18 microg/l), followed by SW (96 h LC50: 294 microg/l) with fish at intermediate salinities being the most tolerant (96 h LC50 > 963 microg/l at 10 ppt). This approximately 50-fold, non-linear variation in sensitivity could not be accounted for by Cu speciation or competition among cations but can be explained by physiology. The relative Na(+) gradient from the blood plasma to the water is greatest in FW followed by SW and is smallest at 10 ppt. Regression of Cu toxicity versus the equilibrium potential for Na(+), which reflects the relative Na(+) gradient, revealed that 93% of the variation can be attributed to Na(+) gradients and thus osmoregulatory physiology. Examination of the existing literature on acute Cu toxicity in SW (defined as >25 ppt) confirmed that early life stages generally are most sensitive but this pattern may be attributable to size rather than developmental stage. Regardless of developmental stage and phylogeny, size clearly matters for Cu sensitivity. The existing literature on the influence of salinity on acute Cu toxicity as well as studies of mechanisms of Cu toxicity in fish and invertebrates are reviewed.

  12. Bioconcentration and acute toxicity of polycyclic musks in two benthic organisms (Chironomus riparius and Lumbriculus variegatus).

    PubMed

    Artola-Garicano, Elsa; Sinnige, Theo L; van Holsteijn, Ineke; Vaes, Wouter H J; Hermens, Joop L M

    2003-05-01

    In the current study, the bioconcentration behavior and acute toxicity of two polycyclic musks, Tonalide 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN) and Galaxolide 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexa-methylcyclopenta[gamma]-2-benzopyran (HHCB), were studied in two benthic organisms. Polycyclic musks are frequently used fragrances, and they have been detected in different compartments of the environment. The aim of this study was to fill some empirical data gaps for AHTN and HHCB for benthic organisms. Results show that differences exist between both organisms. Chironomus riparius exhibited bioconcentration factors (BCFs) for AHTN and HHCB substantially lower than predicted for nontransformed organics. The BCFs for both chemicals increased after coexposure of the organism to the cytochrome P450 inhibitor piperonyl butoxide. Thus, the low BCF values were the result of rapid biotransformation of AHTN and HHCB in the midge larvae. Bioconcentration kinetics indicated that both chemicals induced their own cytochrome P450-mediated metabolism. Acute toxicity of AHTN to midge larvae was reduced compared to predicted baseline toxicity and was similar for HHCB. Bioconcentration of AHTN and HHCB in the worm (Lumbriculus variegatus) is in agreement with predictions based on the octanol-water partition coefficients of these chemicals. Acute toxicity was found to be similar to predicted values for baseline toxicity. Summarizing, for AHTN and HHCB, acute toxicity and bioconcentration behavior in L. variegatus was in accordance with predicted data for nontransformed organics. In C. riparius, bioconcentration as well as toxicity were reduced.

  13. The Acute, Aquatic Toxicity of Selected Mineral Particles

    DTIC Science & Technology

    1988-11-01

    COSATI CODES 18. SUBJECT TERMS (Continue on reverse if necessary and identify by block number) FIELD GROUP SUB-GROUP Graphite; Daphnia magna " 06 1i Nickel...whiskers, nickel-graphite fibers, and synthetic graphite Micro-260 (M-260). Each compound was tested against the cladoceran, Daphnia magna (D. Magna ...graphite fibers, polycrystalline iron whiskers, and graphite Micro-260 (M-260) were tested to determine their toxicities to Daphnia mag . The

  14. Assessment of Acute Toxicity of Hexachloroethane in Laboratory Animals

    DTIC Science & Technology

    1978-01-09

    camphoraceous odor, readily sublimes without meltinq and is solubl,: in alcohol. benzene, chloroform, ether and oil: insoluble in water. It is used as a solvent...in explosives, as ý camphor suostitute in celluloid, and as a rubber vulcanizing accelerator.’ It is used in veterinary practice as an anthelminthic...moderately toxic orally, produced reversible eye irritation and little or no skin irritation. Although it sublimes at room temperature

  15. An evaluation of the bioavailability and aquatic toxicity attributed to ambient zinc concentrations in fresh surface waters from several parts of the world.

    PubMed

    Van Genderen, Eric; Adams, William; Cardwell, Rick; Volosin, Joe; Santore, Robert; Rodriguez, Patricio

    2009-07-01

    Ambient concentrations of metals in surface waters have become an important consideration when establishing water quality criteria and conducting risk assessments. This study sought to estimate amounts of zinc that may be released into freshwater considering ambient concentrations, toxicity thresholds, and bioavailability. Cumulative distribution functions of ambient zinc concentrations were compared statistically for streams and lakes in Europe, North America, and South America to identify differences among mean distribution variables (e.g., slopes, intercepts, and inflection points). Results illustrated that most of the distributions among sites differed significantly. These differences illustrate the variability in ambient zinc concentrations in surface waters because of geographic location, regional geology, and anthropogenic influence. Additionally, water quality data were used to estimate bioavailable zinc concentrations in ambient surface waters (based on predictions using biotic ligand models). The amount of dissolved metal that could be added to surface waters without exceeding toxicity thresholds was calculated by subtracting ambient surface water concentrations from chronic no observable effect concentrations (NOEC; reproduction for Daphnia magna) or 10% effective concentrations (EC10; growth rate for Pseudokirchneriella subcapitata). Because ambient dissolved-zinc concentrations were, on average, below predicted effects thresholds, an average of 57.1 +/- 175 microg/L (+/- SD) of zinc could be added before exceeding the D. magna chronic NOEC or the P. subcapitata chronic EC10. However, numerous sites (17%) were identified as having ambient zinc concentrations in excess of these toxicity thresholds. This article uses existing biotic ligand models for zinc to estimate the potential magnitudes and variabilities of bioavailable zinc concentrations in fresh surface waters from different regions of the world.

  16. Primary chemical and physical characterization of acute toxic components in wastewaters

    SciTech Connect

    Svenson, A.; Linlin, Z.; Kaj, L. )

    1992-10-01

    A chemical and physical primary characterization work sheet was developed based on the Microtox test, a bacterial bioluminescence system used as a rapid estimate of acute aquatic toxic effects. Measurements of the variation in light reduction upon different pretreatments provided information about the chemical and physical properties of the main toxic component(s) in test wastewater samples. This primary characterization of a wastewater sample was performed within 1 day. Tests of pure toxic chemical compounds and wastewaters with known and unknown primary toxicants are presented. Outlines to the chemical analysis and identification of toxic components may be deduced from the primary characterization. The provisional characterization may also provide information on wastewater treatment techniques.

  17. Uptake and toxicity of nano-ZnO in the plant-feeding nematode, Xiphinema vuittenezi: the role of dissolved zinc and nanoparticle-specific effects.

    PubMed

    Sávoly, Zoltán; Hrács, Krisztina; Pemmer, Bernhard; Streli, Christina; Záray, Gyula; Nagy, Péter István

    2016-05-01

    Nanoparticulate ZnO is one of the most commonly applied nanomaterials. As ZnO is more soluble than many other oxide nanoparticles, its toxicity beyond the nanoparticle-specific effects can be attributed to the dissolved ionic zinc. The investigation of uptake and toxicity of nano-ZnO in the plant-feeding nematode, Xiphinema vuittenezi, which was used in previous studies as a biological model organism, was aimed. The establishment of the role of dissolved zinc and nanoparticle-specific effects in the toxicity was also the objective of our study. Zn uptake was found to be significantly higher for bulk and nano-ZnO than for ZnSO4 solution; however, treatments caused loss of potassium in the worms in a dissolved-zinc-dependent manner. The toxicity was the lowest for bulk ZnO, and it was very similar for nano-ZnO and ZnSO4 solution. Accordingly, the toxicity of ZnO nanoparticles is a combination of dissolved-zinc-caused toxicity and nanoparticle-specific effects.

  18. Bicarbonate toxicity to Ceriodaphnia dubia and the freshwater shrimp Paratya australiensis and its influence on zinc toxicity.

    PubMed

    Vera, Carolina Lopez; Hyne, Ross V; Patra, Ron; Ramasamy, Sunderam; Pablo, Fleur; Julli, Moreno; Kefford, Ben J

    2014-05-01

    Bicarbonate is often a major ionic constituent associated with produced waters from methane gas extraction and coal mining, yet few studies have determined its specific toxicity. Currently, the environmental risk of bicarbonate anion in water discharges is assessed based on the toxicity of sodium chloride or artificial seawater and is regulated via electrical conductivity. Increased NaHCO(3) added to Ceriodaphnia dubia in synthetic or natural water gave similar 48-h 10% effective concentration (EC10) values of 1750 ± 125 mg NaHCO(3)/L (mean ± standard error) and 1670 ± 180 mg NaHCO(3)/L, respectively. Bicarbonate was toxic to C. dubia in both waters with conductivities above 1900 µS/cm. In contrast, when conductivity was elevated with NaCl, toxicity to C. dubia was observed only above 2800 µS/cm. Bicarbonate also impaired C. dubia reproduction with an EC10 of 340 mg NaHCO(3)/L. Major ion composition also influenced Zn bioavailability, a common co-occurring metal contaminant in coal mine waters, with sublethal concentrations of NaHCO(3) and elevated pH increasing Zn toxicity. Higher pH was the dominant parameter determining a 10-fold increase in the 48-h 50% effective concentration (EC50) for Zn toxicity to C. dubia at pH 8.6 of 34 µg Zn/L (95% confidence limit = 32-37 µg Zn/L) compared with the Zn toxicity at approximately circumneutral pH. Exposure of the freshwater shrimp Paratya australiensis (Atyidae) in natural water to increasing bicarbonate gave a mean 10-d 10% lethal concentration (LC10) of 850 ± 115 mg NaHCO(3)/L, associated with a mean conductivity EC10 of 1145 µS/cm, which is considerably lower than toxicity of NaCl and artificial seawater to this species reported elsewhere. Because toxicity was influenced by salt composition, specific ions should be regulated rather than conductivity alone in mine wastewater discharges.

  19. Interacting effects of pH acclimation, and pH and heavy metals on acute and chronic toxicity to Ceriodaphnia dubia (Cladocera)

    SciTech Connect

    Belanger, S.E.; Cherry, D.S. )

    1990-05-01

    Understanding the factors that modify the sensitivity of the zooplankton Ceriodaphnia dubia to toxicants is important to the interpretation of chronic toxicity data generated for granting industrial permits. Early reports of high sensitivity of Ceriodaphnia to brief pH excursions led toxicologists to question the use of C. dubia as a test organism. Acute and chronic toxicity of pH and heavy metals, pH acclimation to acidic and alkaline conditions and the role of pH in modifying heavy metal (copper and zinc) toxicities were investigated. Ceriodaphnia dubia acclimated near neutral pH had acute (48-hr) lethal concentrations of 4.6 and 10.3 SU. Reproduction and mortality were not impaired between pH 6.14-8.99 regardless of pH acclimation history. Reproduction was significantly impaired beyond these extremes. Acute exposures to both heavy metals at pH 6, 8 and 9 and in water hardness of 180, 110 and 100 mg/L showed C dubia was consistently most sensitive in low pH and low hardness waters. Reproduction and mortality were not so affected by pH in chronic exposures. Similar concentrations of metals at all pH levels resulted in equivalent reductions in offspring per female. The results strongly suggest that effluent guidelines for pH at 6-9 are sound, and that toxicant activity in chronic time frames is directed primarily by concentration and water hardness, not by pH. 34 refs., 2 figs., 8 tabs.

  20. AGE-RELATED TOXICITY PATHWAY ANALYSIS IN BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

    EPA Science Inventory

    The influence of aging on susceptibility to environmental exposures is poorly understood. To investigate-the contribution of different life stages on response to toxicants, we examined the effects of an acute exposure to the volatile organic compound, toluene (0.0 or 1.0 g/kg), i...

  1. T cell abundance in blood predicts acute organ toxicity in chemoradiotherapy for head and neck cancer

    PubMed Central

    Reichardt, Sybille D.; Rave-Fränk, Margret; Schirmer, Markus A.; Stadelmann, Christine; Canis, Martin; Wolff, Hendrik A.

    2016-01-01

    Treatment of head and neck squamous cell carcinoma (HNSCC) by chemoradiotherapy (CRT) often results in high-grade acute organ toxicity (HGAOT). As these adverse effects impair the patients' quality of life and the feasibility of the planned therapy, we sought to analyze immunological parameters in tumor material and blood samples obtained from 48 HNSCC patients in order to assess the potential to predict the individual acute organ toxicity. T cells in the tumor stroma were enriched in patients developing HGAOT whereas levels of soluble factors in the plasma and gene expression in whole blood did not coincide with the occurrence of acute organ toxicity. In contrast, the frequency and absolute numbers of selected leukocyte subpopulations measured in samples of peripheral blood mononuclear cells (PBMCs) directly before the beginning of CRT were significantly different in patients with HGAOT as compared to those without. When we validated several potential markers including the abundance of T cells in a small prospective study with 16 HNSCC patients, we were able to correctly predict acute organ toxicity in up to 81% of the patients. We conclude that analysis of PBMCs by fluorescence-activated cell sorting (FACS) might be a convenient strategy to identify patients at risk of developing HGAOT caused by CRT, which might allow to adapt the treatment regimen and possibly improve disease outcome. PMID:27589568

  2. EVALUATION OF MINIMUM DATA REQUIREMENTS FOR ACUTE TOXICITY VALUE EXTRAPOLATION WITH AQUATIC ORGANISMS

    EPA Science Inventory

    Buckler, Denny R., Foster L. Mayer, Mark R. Ellersieck and Amha Asfaw. 2003. Evaluation of Minimum Data Requirements for Acute Toxicity Value Extrapolation with Aquatic Organisms. EPA/600/R-03/104. U.S. Environmental Protection Agency, National Health and Environmental Effects Re...

  3. Partial Life-Cycle and Acute Toxicity of Perfluoroalkyl Acids to Freshwater Mussels

    EPA Science Inventory

    Freshwater mussels are among the most sensitive aquatic organisms to many contaminants and have complex life-cycles that include several distinct life stages with unique contaminant exposure pathways. Standard acute (24–96 h) and chronic (28 d) toxicity tests with free larva (glo...

  4. ACUTE AND CHRONIC TOXICITY OF BREVETOXIN TO OYSTERS AND GRASS SHRIMP

    EPA Science Inventory

    Walker, Calvin C., James T. Winstead, Steven S. Foss, Janis C. Kurtz, James Watts, Jeanne E. Scott and William S. Fisher. In press. Acute and Chronic Toxicity of Brevetoxin to Oysters and Grass Shrimp (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November ...

  5. EXTRAPOLATION OF ACUTE TOXICITY AMONG AQUATIC SPECIES BASED ON MECHANISM OF ACTION

    EPA Science Inventory

    Presentation provides inter-species QSARs for acute toxicity to ciliates, fish and daphnia...The inter-species QSARs can be also useful in the analysis of the relative species sensitivity to a variety of pollutants and will be useful in assisting in risk assessments of potential ...

  6. TOXICITY PATHWAY ANALYSIS IN AGING BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE

    EPA Science Inventory

    The influence of aging on susceptibility to environmental stressors is poorly understood. To investigate the contribution of different life stages on response to toxicants, we examined the effects of acute exposure by oral gavage of the volatile organic solvent toluene (0.00, 0.3...

  7. WEB-BASED INTERSPECIES CORRELATION ESTIMATION (WEB-ICE) FOR ACUTE TOXICITY: USER MANUAL V2

    EPA Science Inventory

    Predictive toxicological models are integral to environmental risk Assessment where data for most species are limited. Web-based Interspecies Correlation Estimation (Web-ICE) models are least square regressions that predict acute toxicity (LC50/LD50) of a chemical to a species, ...

  8. Acute toxicity of peracetic acid (PAA) formulations to Ichthyophthirius multifiliis theronts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peracetic acid (PAA) is an antimicrobial disinfectant used in agriculture, food processing and medical facilities. It has recently been suggested as a means to control infestations of Ichthyophthirius multifiliis. The purpose of this study was to determine the acute toxicity of two products contai...

  9. Comparative toxicities of aluminum and zinc from sacrificial anodes or from sulfate salt in sea urchin embryos and sperm.

    PubMed

    Caplat, Christelle; Oral, Rahime; Mahaut, Marie-Laure; Mao, Andrea; Barillier, Daniel; Guida, Marco; Della Rocca, Claudio; Pagano, Giovanni

    2010-09-01

    The toxicity of aluminum or zinc from either sacrificial anodes (SA) or their sulfate salts (SS) was evaluated in sea urchin (Paracentrotus lividus) embryos or sperm exposed to Al(III) or Zn(II) (SA or SS, 0.1-10 microM), scoring developmental defects (DDs), fertilization rate (FR), and mitotic abnormalities. A significant DD increase was observed in SS, but not SA Al(III)- and Zn(II)-exposed embryos vs. controls. Both Al(III) and Zn(II), up to 10 microM, from SA and SS, inhibited mitotic activity and induced mitotic aberrations in exposed embryos. SA-Al(III)-exposed sperm displayed a significant FR increase, unlike Al(III) sulfate overlapping with controls. Both SA-Zn(II) and Zn(II) sulfate sperm exposure resulted in a significant FR increase. The offspring of SA-Al(III)-exposed sperm displayed a significant DD decrease, unlike Al(III) sulfate exposure. Zinc sulfate sperm exposure resulted in a significant increase in offspring DDs, whereas SA-Zn(II) sperm exposure decreased DDs. Together, exposures to SA-dissolved Al(III) or Zn(II) resulted in lesser, if any toxicity, up to hormesis, compared to SS. Studies of metal speciation should elucidate the present results.

  10. Toxicity and transcriptomic analysis in Hyalella azteca suggests increased exposure and susceptibility of epibenthic organisms to zinc oxide nanoparticles.

    PubMed

    Poynton, Helen C; Lazorchak, James M; Impellitteri, Christopher A; Blalock, Bonnie; Smith, Mark E; Struewing, Katherine; Unrine, Jason; Roose, Deborah

    2013-08-20

    Nanoparticles (NPs) are expected to make their way into the aquatic environment where sedimentation of particles will likely occur, putting benthic organisms at particular risk. Therefore, organisms such as Hyalella azteca, an epibenthic crustacean which forages at the sediment surface, is likely to have a high potential exposure. Here we show that zinc oxide (ZnO) NPs are more toxic to H. azteca compared with the corresponding metal ion, Zn(2+). Dissolution of ZnO NPs contributes about 50% of the Zn measured in the ZnO NP suspensions, and cannot account for the toxicity of these particles to H. azteca. However, gene expression analysis is unable to distinguish between the ZnO NP exposures and zinc sulfate (ZnSO4) exposures at equitoxic concentrations. These results lead us to hypothesize that ZnO NPs provide an enhanced exposure route for Zn(2+) uptake into H. azteca, and possibly other sediment dwelling organisms. Our study supports the prediction that sediment dwelling organisms are highly susceptible to the effects of ZnO NPs and should be considered in the risk assessment of these nanomaterials.

  11. Acute and chronic toxicity of lead in water and diet to the amphipod Hyalella azteca

    USGS Publications Warehouse

    Besser, J.M.; Brumbaugh, W.G.; Brunson, E.L.; Ingersoll, C.G.

    2005-01-01

    We evaluated the influence of waterborne and dietary lead (Pb) exposure on the acute and chronic toxicity of Pb to the amphipod Hyalella azteca. Test solutions were generated by a modified diluter with an extended (24-h) equilibration period. Acute (96-h) toxicity of Pb varied with water hardness in the range of 71 to 275 mg/L as CaCO3, despite similar dissolved Pb concentrations. Acute toxicity was greatest in soft test water, with less than 50% survival at the lowest dissolved Pb concentration (151 ??g/L). Survival also was significantly reduced in medium-hardness water but not in hard test water. In chronic (42-d) studies, amphipods were exposed to waterborne Pb and fed either a control diet or a diet equilibrated with waterborne Pb levels. For animals fed the control diet, the median lethal concentration (LC50) for Pb was 24 ??g/L (as dissolved Pb), and significant reductions in survival occurred at 16 ??g/L. Exposure to Pb-treated diets significantly increased toxicity across a wide range of dissolved Pb concentrations, with a LC50 of 16 ??g/L and significant reductions in growth and reproduction at 3.5 ??g/L. Significant effects on growth and reproduction occurred at dissolved Pb concentrations close to the current U.S. chronic water-quality criterion. Our results suggest that both aqueous- and dietary-exposure pathways contribute significantly to chronic Pb exposure and toxic effects in aquatic biota. ?? 2005 SETAC.

  12. Safety assessment of methanol extract of red dragon fruit (Hylocereus polyrhizus): acute and subchronic toxicity studies.

    PubMed

    Hor, Sook Yee; Ahmad, Mariam; Farsi, Elham; Yam, Mun Fei; Hashim, Mohd Akmal; Lim, Chung Pin; Sadikun, Amirin; Asmawi, Mohd Zaini

    2012-06-01

    Recently, the fruits of Hylocereus polyrhizus, known as red dragon fruit, have received much attention from growers worldwide. However, there is little toxicological information regarding the safety of repeated exposure to these fruits. The present study evaluated the potential toxicity of a methanol extract of H. polyrhizus fruit after acute and subchronic administration in rats. In the acute toxicity study, single doses of fruit extract (1250, 2500 and 5000 mg/kg) were administered to rats by oral gavage, and the rats were then monitored for 14 days. In the subchronic toxicity study, the fruit extract was administered orally to rats at doses of 1250, 2500 and 5000 mg/kg/day for 28 days. There was no mortality or signs of acute or subchronic toxicity. There was no significant difference in body weight, relative organ weight or hematological parameters in the subchronic toxicity study. Biochemical analysis showed some significant changes, including creatinine, globulin, total protein and urea levels. No abnormality of internal organs was observed between treatment and control groups. The lethal oral dose of the fruit extract is more than 5000 mg/kg and the no-observed-adverse-effect level (NOAEL) of the extract for both male and female rats is considered to be 5000 mg/kg per day for 28 days.

  13. Critique on the use of the standardized avian acute oral toxicity test for first generation anticoagulant rodenticides

    USGS Publications Warehouse

    Vyas, Nimish B.; Rattner, Barnett A.

    2012-01-01

    Avian risk assessments for rodenticides are often driven by the results of standardized acute oral toxicity tests without regards to a toxicant's mode of action and time course of adverse effects. First generation anticoagulant rodenticides (FGARs) generally require multiple feedings over several days to achieve a threshold concentration in tissue and cause adverse effects. This exposure regimen is much different than that used in the standardized acute oral toxicity test methodology. Median lethal dose values derived from standardized acute oral toxicity tests underestimate the environmental hazard and risk of FGARs. Caution is warranted when FGAR toxicity, physiological effects, and pharmacokinetics derived from standardized acute oral toxicity testing are used for forensic confirmation of the cause of death in avian mortality incidents and when characterizing FGARs' risks to free-ranging birds.

  14. Toxicity assessment of the antifouling compound zinc pyrithione using early developmental stages of the ascidian Ciona intestinalis.

    PubMed

    Bellas, Juan

    2005-01-01

    This study investigated the toxicity of zinc pyrithione (Zpt) on the early stages of development of the ascidian Ciona intestinalis. Larval morphological abnormalities were studied after the exposure of C. intestinalis embryos at different stages of development. The median effective concentrations (EC50) ranged from 226-590 nM. The larval settlement stage was the most sensitive to Zpt. Toxic effects of Zpt on larval settlement were detected at 9 nM (EC10). The inhibition of C. intestinalis embryonic development was also used to study the loss of toxicity in Zpt solutions exposed to direct sunlight and laboratory UV light. The results showed that the toxicity of Zpt solutions decreased but did not disappear after 4 h exposure to direct sunlight (EC50 = 484 nM) or UV light (EC50 = 453 nM), compared to control Zpt solutions prepared in dark conditions. On the basis of the present data, predicted no effect concentrations of Zpt to C. intestinalis larvae are lower than predicted environmental concentrations of Zpt in certain polluted areas and therefore, may pose a risk to C. intestinalis populations.

  15. [Clinical and immunological features of acute hepatitis B in patients with concomitant chronic toxic liver damage].

    PubMed

    Furyk, E; Ryabokon, E

    2013-02-01

    The article presents information obtained during the survey in 64 patients with acute hepatitis B. We show that acute hepatitis B in patients with concomitant chronic toxic liver characterized by a marked imbalance of cytokine status due to a lower level of interleukin-2 and a higher content of interleukin-8, the highest levels of nitrite content, spontaneous oxidative modifications of blood proteins and the lowest content of L -arginine in the blood serum in the dynamics of disease compared with patients without this concomitant factor. In the period of convalescence these changes in patients with acute hepatitis B with concomitant chronic toxic liver characterized combined with higher cytolysis of liver cells, often circulating in the blood of HBsAg seroconversion and less frequently with the advent of anti-HBeAg.

  16. Acute oral toxicity of Pereskia bleo and Pereskia grandifolia in mice

    PubMed Central

    Sim, K. S.; Sri Nurestri, A. M.; Sinniah, S. K.; Kim, K. H.; Norhanom, A. W.

    2010-01-01

    Pereskia bleo and Pereskia grandifolia, belonging to the botanical family Cactaceae, have been traditionally used by the locals in Malaysia for treatment of various ailments. The current study reports the outcome of acute oral toxicity investigation of Pereskia bleo and Pereskia grandifolia, on ICR mice. No mortalities or evidence of adverse effects have been observed in ICR mice following acute oral administration at the highest dose of 2500 mg/ kg crude extracts of Pereskia bleo and Pereskia grandifolia. This is the first report on the acute oral toxicity of Pereskia bleo and Pereskia grandifolia and the findings of this study are in agreement with those of in vitro experiments and thus provide scientific validation on the use of the leaves of Pereskia bleo and Pereskia grandifolia. PMID:20548939

  17. Acute Exposure Guideline Levels (AEGLs) for Time Varying Toxic Plumes

    DTIC Science & Technology

    2014-09-12

    package, which we are calling EAGLE, in the sections below. The package contains the tabulated AEGL data for chlorine (CL2) and ammonia (NH3) at...200C. The molecular weight for chlorine (CL2) is MW = 70.9 and for ammonia (NH3), MW = 17.03. Figure 1 just below reproduces the chlorine table...below shows the same information as Table 1, but for ammonia . The toxicity levels are 50 or 60 times lower than for chlorine, but the behavior with

  18. Acute Oral Toxicity Potential of 4-Nitrophenyl Methkyl Phenyl Phosphinate.

    DTIC Science & Technology

    1982-09-01

    methyl phenyl phosphinate Chemical Abstract Service Registry No.: None Molecular structure: C Ii NO P 13 12 4 .0 0~ NO., CH3 o o...C 56.33 56.17 H 4.36 4.28 N 5.05 5.14 P 11.17 11.25 2. Chemical Name: Polysorbate 80 (Tween 80) Chemical Abstract Service Registry No.: 9005-65-6...administration particularly in chronic toxicity studies in experimental data. 3. Chemical Name: Citric Acid, monohydrate Chemical Abstract Service

  19. Antineoplastic activity of ouabain and pyrithione zinc in acute myeloid leukemia.

    PubMed

    Tailler, M; Senovilla, L; Lainey, E; Thépot, S; Métivier, D; Sébert, M; Baud, V; Billot, K; Fenaux, P; Galluzzi, L; Boehrer, S; Kroemer, G; Kepp, O

    2012-07-26

    Despite recent progress in the treatment of acute myeloid leukemia (AML), the prognosis of this rather heterogeneous disease remains poor and novel chemotherapeutics that specifically target leukemic cells must be developed. To address this need at the preclinical level, we implemented a high content imaging-based screen for the identification of small agents that induce AML cell death in vitro. Among a panel of 1040 Food and Drug Administration-approved agents, we identified pyrithione zinc (PZ) and ouabain (OUA) as potential antileukemic compounds. Both PZ and OUA efficiently induced cell death associated with apoptotic chromatin condensation and inhibition of nuclear factor-κB survival signaling, leading to reduced expression of antiapoptotic proteins, in several AML cell lines. PZ- and OUA-induced cell death was associated with the permeabilization of the outer mitochondrial membrane and led to the release of cytochrome c followed by caspase activation. Both PZ and OUA exerted significant anticancer effects in vivo, on human AML cells xenografts as well as ex vivo, on CD34(+) (but not CD34(-)) malignant myeloblasts from AML patients. Altogether, our results suggest that PZ and OUA may exhibit antileukemic effects by inducing the apoptotic demise of AML cells.

  20. Acute and chronic toxicity toward the bacteria Vibrio fischeri of organic narcotics and epoxides: structural alerts for epoxide excess toxicity.

    PubMed

    Blaschke, Ulrike; Paschke, Albrecht; Rensch, Ines; Schüürmann, Gerrit

    2010-12-20

    The acute and chronic bacterial toxicity of 34 organic compounds comprising 19 baseline narcotics and 15 epoxides has been determined with regard to 30-min bioluminescence and 24-h growth inhibition in terms of EC50 (effective concentration 50%) values employing Vibrio fischeri. For the narcotics, linear regression of log EC50 on log Kow (octanol/water partition coefficient) yields r2 (squared correlation coefficient) and rms (root-mean-square error) values of 0.95 and 0.44 (30-min), and 0.94 and 0.34 (24-h), respectively. Employing the resultant baseline narcosis models, toxicity enhancement (Te) values were derived as a ratio of narcosis-predicted over experimental EC50 for the epoxides. For seven aliphatic epoxides, log Te was below 1 in both assays, indicating narcosis-range toxicity with regard to 30-min bioluminescence and 24-h growth inhibition. Concerning eight nonaliphatic epoxides, log Te values up to 2.4 were observed, reflecting excess toxicity through an enhanced electrophilic reactivity of the compounds. Here, however, the intercorrelation between both assays was very low (r2 = 0.09). The results are discussed in terms of electronic substituent effects activating an SN2-type epoxide reaction with nucleophilic protein sites and side-chain activation offering alternative electrophile-nucleophile reaction routes at side-chain sites, leading to respective structural alerts as indicators of excess toxicity. Surprisingly, 30-min bioluminescence appears to be slightly more sensitive to chemical stress than 24-h growth, which holds both for baseline narcotics and for most of the epoxides. This is also reflected by effective narcosis doses 50%, ED50, of 7.1 mmol/kg (30-min) and 7.7 mmol/kg (24-h) estimated from narcosis theory. Keeping in mind the different end points (bioluminescence vs growth) involved, this finding demonstrates that chronic toxicity is not always more sensitive than acute toxicity, calling for analyses with regard to further respective

  1. Prediction of acute toxicity of chemicals in mixtures: worms Tubifex tubifex and gas/liquid distribution.

    PubMed

    Tichý, M; Borek-Dohalský, V; Matousová, D; Rucki, M; Feltl, L; Roth, Z

    2002-03-01

    The aim of this contribution is to support our proposal of the procedure for predicting acute toxicity of binary mixtures by QSAR analysis techniques. The changes of a mixture composition are described by molar ratio R and visualized in the R-plot (QCAR--quantitative composition-activity relationships). The approach was inspired by Rault and Dalton's laws, their positive and negative deviations in the behavior of a mixture of real gases, by Loewe and Muischnek isoboles and by the Finney test of additivity. Acute toxicity was determined by the laboratory test with woms Tubifex tubifex. The additivity of the acute toxicity in the binary mixture benzene + nitrobenzene was confirmed and a new interaction is described: "mixed interaction" with the binary mixture aniline + ethanol. The "mixed interaction" means that depending on mixture composition, both potentiation and inhibition can occur. As the first physicochemical descriptor of the changes caused by the changing composition of binary mixtures, the gas/liquid equilibrium was studied and a composition of the gaseous phase was determined by a gas chromatographic method. The method for determination of concentrations in the gaseous phase was described. The gaseous phase composition of benzene + nitrobenzene. benzene + ethanol, benzene + aniline and ethanol + aniline mixtures was analyzed. It was found that if the concentrations of the mixture's components in the gaseous phase behave nonideally (they are not additive), the acute toxicity of the same mixture is not additive as well. Another descriptor to distinguish between potentiation and inhibition will be, however, necessary. The properties, both gaseous phase composition and the acute toxicity, of the benzene + nitrobenzene mixture are additive. In mixtures with the mixed interaction, the R-plot of the composition of the gaseous phase is complex with a large variation of results.

  2. Acute and subacute oral toxicity of Litsea elliptica Blume essential oil in rats*

    PubMed Central

    Budin, Siti Balkis; Siti Nor Ain, Seri Masran; Omar, Baharuddin; Taib, Izatus Shima; Hidayatulfathi, Othman

    2012-01-01

    Litsea elliptica Blume has been traditionally used to treat headache, fever, and stomach ulcer, and has also been used as an insect repellent. The acute and subacute toxicities of L. elliptica essential oil were evaluated orally by gavage in female Sprague-Dawley rats. For the acute toxicity study, L. elliptica essential oil was administered in doses from 500 to 4 000 mg/kg (single dose), and in the subacute toxicity test, the following doses were used: 125, 250, and 500 mg/kg, for 28 consecutive days. In the acute toxicity study, L. elliptica essential oil caused dose-dependent adverse behaviours and mortality. The median lethal dose value was 3 488.86 mg/kg and the acute non-observed-adversed-effect level value was found to be 500 mg/kg. The subacute toxicity study of L. elliptica essential oil did not reveal alterations in body weight, and food and water consumptions. The haematological and biochemical analyses did not show significant differences between control and treated groups in most of the parameters examined, except for the hemoglobin, mean cell hemoglobin concentration, mean cell volume, mean cell hemoglobin, serum albumin, and serum sodium. However, these differences were still within the normal range. No abnormalities or histopathological changes were observed in the liver, pancreatic islet of Langerhans, and renal glomerulous and tubular cells of all treated groups. In conclusion, L. elliptica essential oil can be classified in the U group, which is defined as a group unlikely to present an acute hazard according to World Health Organization (WHO) classification. PMID:23024045

  3. Acute toxicity of hypofractionated intensity-modulated radiotherapy for prostate cancer

    PubMed Central

    Drodge, C.S.; Boychak, O.; Patel, S.; Usmani, N.; Amanie, J.; Parliament, M.B.; Murtha, A.; Field, C.; Ghosh, S.; Pervez, N.

    2015-01-01

    Background Dose-escalated hypofractionated radiotherapy (hfrt) using intensity-modulated radiotherapy (imrt), with inclusion of the pelvic lymph nodes (plns), plus androgen suppression therapy (ast) in high-risk prostate cancer patients should improve patient outcomes, but acute toxicity could limit its feasibility. Methods Our single-centre phase ii prospective study enrolled 40 high-risk prostate cancer patients. All patients received hfrt using imrt with daily mega-voltage computed tomography imaging guidance, with 95% of planning target volumes (ptv68 and ptv50) receiving 68 Gy and 50 Gy (respectively) in 25 daily fractions. The boost volume was targeted to the involved plns and the prostate (minus the urethra plus 3 mm and minus 3 mm from adjacent rectal wall) and totalled up to 75 Gy in 25 fractions. Acute toxicity scores were recorded weekly during and 3 months after radiotherapy (rt) administration. Results For the 37 patients who completed rt and the 3-month follow-up, median age was 65.5 years (range: 50–76 years). Disease was organ-confined (T1c–T2c) in 23 patients (62.1%), and node-positive in 5 patients (13.5%). All patients received long-term ast. Maximum acute genitourinary (gu) and gastrointestinal (gi) toxicity peaked at grade 2 in 6 of 36 evaluated patients (16.6%) and in 4 of 31 evaluated patients (12.9%) respectively. Diarrhea and urinary frequency were the chief complaints. Dose–volume parameters demonstrated no correlation with toxicity. The ptv treatment objectives were met in 36 of the 37 patients. Conclusions This hfrt dose-escalation trial in high-risk prostate cancer has demonstrated the feasibility of administering 75 Gy in 25 fractions with minimal acute gi and gu toxicities. Further follow-up will report late toxicities and outcomes. PMID:25908924

  4. Acute and chronic toxicity of sodium sulfate to four freshwater organisms in water-only exposures

    USGS Publications Warehouse

    Wang, Ning; Consbrock, Rebecca A.; Ingersoll, Christopher G.; Hardesty, Douglas K.; Brumbaugh, William G.; Hammer, Edward J.; Bauer, Candice R.; Mount, David R.

    2016-01-01

    The acute and chronic toxicity of sulfate (tested as sodium sulfate) was determined in diluted well water (hardness of 100 mg/L and pH 8.2) with a cladoceran (Ceriodaphnia dubia; 2-d and 7-d exposures), a midge (Chironomus dilutus; 4-d and 41-d exposures), a unionid mussel (pink mucket, Lampsilis abrupta; 4-d and 28-d exposures), and a fish (fathead minnow, Pimephales promelas; 4-d and 34-d exposures). Among the 4 species, the cladoceran and mussel were acutely more sensitive to sulfate than the midge and fathead minnow, whereas the fathead minnow was chronically more sensitive than the other 3 species. Acute-to-chronic ratios ranged from 2.34 to 5.68 for the 3 invertebrates but were as high as 12.69 for the fish. The fathead minnow was highly sensitive to sulfate during the transitional period from embryo development to hatching in the diluted well water, and thus, additional short-term (7- to 14-d) sulfate toxicity tests were conducted starting with embryonic fathead minnow in test waters with different ionic compositions at a water hardness of 100 mg/L. Increasing chloride in test water from 10 mg Cl/L to 25 mg Cl/L did not influence sulfate toxicity to the fish, whereas increasing potassium in test water from 1mg K/L to 3mg K/L substantially reduced the toxicity of sulfate. The results indicate that both acute and chronic sulfate toxicity data, and the influence of potassium on sulfate toxicity to fish embryos, need to be considered when environmental guidance values for sulfate are developed or refined.

  5. Acute and chronic toxicity of sodium sulfate to four freshwater organisms in water-only exposures.

    PubMed

    Wang, Ning; Dorman, Rebecca A; Ingersoll, Christopher G; Hardesty, Doug K; Brumbaugh, William G; Hammer, Edward J; Bauer, Candice R; Mount, David R

    2016-01-01

    The acute and chronic toxicity of sulfate (tested as sodium sulfate) was determined in diluted well water (hardness of 100 mg/L and pH 8.2) with a cladoceran (Ceriodaphnia dubia; 2-d and 7-d exposures), a midge (Chironomus dilutus; 4-d and 41-d exposures), a unionid mussel (pink mucket, Lampsilis abrupta; 4-d and 28-d exposures), and a fish (fathead minnow, Pimephales promelas; 4-d and 34-d exposures). Among the 4 species, the cladoceran and mussel were acutely more sensitive to sulfate than the midge and fathead minnow, whereas the fathead minnow was chronically more sensitive than the other 3 species. Acute-to-chronic ratios ranged from 2.34 to 5.68 for the 3 invertebrates but were as high as 12.69 for the fish. The fathead minnow was highly sensitive to sulfate during the transitional period from embryo development to hatching in the diluted well water, and thus, additional short-term (7- to 14-d) sulfate toxicity tests were conducted starting with embryonic fathead minnow in test waters with different ionic compositions at a water hardness of 100 mg/L. Increasing chloride in test water from 10 mg Cl/L to 25 mg Cl/L did not influence sulfate toxicity to the fish, whereas increasing potassium in test water from 1 mg K/L to 3 mg K/L substantially reduced the toxicity of sulfate. The results indicate that both acute and chronic sulfate toxicity data, and the influence of potassium on sulfate toxicity to fish embryos, need to be considered when environmental guidance values for sulfate are developed or refined.

  6. Acute toxicity of selected herbicides and surfactants to larvae of the midge Chironomus riparius

    USGS Publications Warehouse

    Buhl, Kevin J.; Faerber, Neil L.

    1989-01-01

    The acute toxicities of eight commercial herbicides and two surfactants to early fourth instar larvae of the midgeChironomus riparius were determined under static conditions. The formulated herbicides tested were Eradicane® (EPTC), Fargo® (triallate), Lasso® (alachlor), ME4 Brominal® (bromoxynil), Ramrod® (propachlor), Rodeo® (glyphosate), Sencor®(metribuzin), and Sutan (+)® (butylate); the two surfactants were Activator N.F.® and Ortho X-77®. In addition, technical grade alachlor, metribuzin, propachlor, and triallate were tested for comparison with the formulated herbicides. The relative toxicity of the commercial formulations, based on percent active ingredient, varied considerably. The EC50 values ranged from 1.23 mg/L for Fargo® to 5,600 mg/L for Rodeo®. Fargo®, ME4 Brominal®, and Ramrod®were moderately toxic to midge larvae; Lasso®, Sutan (+)®, and Eradicane® were slightly toxic; and Sencor® and Rodeo® were practically non-toxic. The 48-hr EC50 values of the two surfactants were nearly identical and were considered moderately toxic to midges. For two of the herbicides in which the technical grade material was tested, the inert ingredients in the formulations had a significant effect on the toxicity of the active ingredients. Fargo® was twice as toxic as technical grade triallate, whereas Sencor® was considerably less toxic than technical grade metribuzin. A comparison of the slope function values indicated that the toxic action of all the compounds occurred within a relatively narrow range. Published acute toxicity data on these compounds for other freshwater biota were tabulated and compared with our results. In general, the relative order of toxicity toC. riparius was similar to those for other freshwater invertebrates and fish. Maximum concentrations of each herbicide in bulk runoff during a projected “critical” runoff event were calculated as a percentage of the application rate lost in a given volume of runoff. A comparison

  7. The acute toxicity of major ion salts to Ceriodaphnia dubia: I. ...

    EPA Pesticide Factsheets

    The ions Na+, K+, Ca2+, Mg2+, Cl-, SO42-, and HCO3-/CO32- (referred to as “major ions”) are present in all fresh waters and are physiologically required by aquatic organisms, but can be increased to harmful levels by a variety of anthropogenic activities that speed geochemical weathering or otherwise introduce or concentrate ions. While toxicity of these ions to aquatic organisms has been previously shown, it is also known that their toxicity can vary depending on the concentrations of other co-occurring anions, and understanding these relationships is key to predicting toxicity and establishing appropriate environmental limits. In this paper we conduct a series of experiments with Ceriodaphnia dubia to evaluate the acute toxicity of all twelve major ionsalts (pairing one of the cations with one of the anions) and to determine how toxicity of these salts varies as a function of background water chemistry. All salts except CaSO4 and CaCO3 were acutely toxic to C. dubia below saturation, with the lowest LC50s found for K salts. Of the remaining salts, all but CaCl2 showed some degree of decreased toxicity as the ionic content of the background water increased. Experiments that independently varied Ca:Mg ratio, Na:K ratio, Cl:SO4 ratio, and alkalinity/pH were used to show that Ca concentration was the primary factor influencing the toxicities of Na and Mg salts. In contrast, the toxicities of K salts were primarily influenced by the concentration of Na. Th

  8. Acute lethal toxicity following passive immunization for treatment of murine cryptococcosis.

    PubMed Central

    Savoy, A C; Lupan, D M; Manalo, P B; Roberts, J S; Schlageter, A M; Weinhold, L C; Kozel, T R

    1997-01-01

    Passive immunization with monoclonal antibodies (MAbs) specific for the major capsular polysaccharide of Cryptococcus neoformans alters the course of murine cryptococcosis. During studies of passive immunization for treatment of murine cryptococcosis, we noted the occurrence of an acute, lethal toxicity. Toxicity was characterized by scratching, lethargy, respiratory distress, collapse, and death within 20 to 60 min after injection of antibody. The toxic effect was observed only in mice with a cryptococcal infection and was reduced or absent in the early and late stages of disease. The clinical course and histopathology were consistent with those for shock. There was considerable variation between mouse strains in susceptibility to toxicity. Swiss Webster mice from the Charles River colony were most susceptible, followed by C3H/He, BALB/c, and C57BL/6 mice. DBA/2 mice and Swiss Webster mice from the Simonsen colony were resistant. Acute toxicity was mimicked by injection of preformed complexes of MAb and purified polysaccharide. The toxic effect was also produced by injection of MAbs into mice that were preloaded with polysaccharide. The toxic effect was not blocked by treatment of mice with chloropheniramine or anti-tumor necrosis factor alpha antibodies or by depletion of complement components via pretreatment with cobra venom factor. Toxicity was reduced by treatment of mice with high doses of epinephrine, dexamethasone, or chlorpromazine. Finally, the toxic effect was completely blocked by treatment of mice with the platelet-activating factor antagonist WEB 2170 BS or by pretreatment of mice with the liposome-encapsulated drug dichloromethylene diphosphonate, a procedure which depletes macrophages from the spleen and liver. PMID:9125564

  9. DOSE-DEPENDENT TRANSITIONS IN MECHANISMS OF TOXICITY: ZINC CASE EXAMPLE

    EPA Science Inventory

    Zinc (Zn) is an essential trace element. Maternal Zn deficiency can result in complications of pregnancy and inadequate supply of Zn to the conceptus can interfere with the development of numerous organ systems. Maternal dietary Zn deficiency has been shown to be teratogenic in a...

  10. Spatial and temporal variation in results of purple urchin (Strongylocentrotus purpuratus) toxicity tests with zinc

    SciTech Connect

    Phillips, B.M.; Anderson, B.S.; Hunt, J.W.

    1998-03-01

    Purple urchins (Strongylocentrotus purpuratus) were maintained in year-round spawning condition in the laboratory for use in fertilization and larval development experiments designed to assess temporal variability in response to zinc. Results of these tests were compared to those from tests using gametes obtained from a field-collected population. Fertilization and larval development tests were also conducted comparing field-collected purple urchins from three geographically distinct groups on the West Coast of the United States. Fertilization tests conducted to assess temporal variability produced variable median effects concentrations (EC50s) ranging from 4.1 to >100 {micro}g/L zinc. Larval development tests did not demonstrate significant differences in response to zinc between geographically distinct purple urchin populations. Fertilization test variability was examined in terms of sperm concentration and sperm collection method during two seasons. Reduced variability was found with dry sperm collection in tests conducted in March 1995 but increased again in tests conducted in June 1995, regardless of sperm collection method. Increased variability in response to zinc may be caused by seasonal temperature effects.

  11. Toxicity to woodlice of zinc and lead oxides added to soil litter

    USGS Publications Warehouse

    Beyer, W.N.; Anderson, A.

    1985-01-01

    Previous studies have shown that high concentrations of metals in soil are associated with reductions in decomposer populations. We have here determined the relation between the concentrations of lead and zinc added as oxides to soil litter and the survival and reproduction of a decomposer population under controlled conditions. Laboratory populations of woodlice (Porcellio scaber Latr) were fed soil litter treated with lead or zinc at concentrations that ranged from 100 to 12,800 ppm. The survival of the adults, the maximum number of young alive, and the average number of young alive, were recorded over 64 weeks. Lead at 12,800 ppm and zinc at 1,600 ppm or more had statistically significant (p < 0.05) negative effects on the populations. These results agree with field observations suggesting that lead and zinc have reduced populations of decomposers in contaminated forest soil litter, and concentrations are similar to those reported to be associated with reductions in natural populations of decomposers. Poisoning of decomposers may disrupt nutrient cycling, reduce the numbers of invertebrates available to other wildlife for food, and contribute to the contamination of food chains.

  12. Effect of cytochrome P450 inhibitors and anticonvulsants on the acute toxicity of acrylonitrile.

    PubMed

    Benz, Frederick W; Nerland, Donald E

    2005-10-01

    Some of the more striking expressions of toxicity are the tremors and seizures observed approximately 100 min after exposure of rats to an acutely toxic dose of acrylonitrile (AN). These early events are followed by a second wave of severe clonic convulsions that occur just prior to death at about 3-4 h. For AN, at least two chemical entities could produce these toxic effects, namely the parent AN molecule, the metabolically-released cyanide, or both. Which of these two agents is responsible for each of the symptoms of acute intoxication is not known. To help dissect the toxicity, it was anticipated that an effective inhibitor of the oxidative metabolism of AN to cyanide could help us to understand which toxic symptoms might be associated with each agent. Three inhibitors of oxidative metabolism were tested, namely SKF-525A, 1-benzylimidazole and metyrapone and one alternative substrate, ethanol. As compared to SKF-525A and metyrapone, both 1-benzylimidazole and ethanol were highly effective in reducing blood cyanide levels to insignificant levels in rats treated with an LD90 dose of AN. In addition, both agents abolished the early seizure activity, suggesting that this first phase of seizures is due to cyanide and not the parent molecule. 1-Benzylimidazole did not prevent the severe clonic convulsive phase preceding death, suggesting that these terminal convulsions are due to the toxic effects of the parent AN molecule. The CNS depressant ethanol was only partially effective in attenuating the terminal convulsions. None of these agents affected the incidence of AN-induced mortality, clearly establishing that, even in the absence of cyanide, the parent AN molecule is acutely toxic. The partial effectiveness of ethanol suggested that anticonvulsants might be of benefit. Both phenobarbital and phenytoin protected rats from both the early and terminal convulsions, while valproic acid was ineffective. These effects were not related to a reduction in blood cyanide

  13. Development of a salinity/toxicity relationship to predict acute toxicity of saline waters to freshwater organisms. Interim final report, June 1990-March 1992

    SciTech Connect

    Mount, D.R.; Gulley, D.D.

    1992-04-01

    Discharge of produced water to surface waters is generally regulated as part of the NPDES permit problem and, therefore, may be subject to discharge limits for aquatic toxicity. Most produced waters contain elevated (relative to fresh water) concentrations of major ions (e.g., sodium, chloride) that can be toxic to fresh water organisms regardless of other organic and inorganic constituents. The objective of the research was to develop a Salinity/Toxicity Relationship (STR) that predicts the acute toxicity of saline waters to freshwater organisms based on the concentrations of major ions in solution. Laboratory toxicity tests were conducted to measure the acute toxicity of major ions to three freshwater species (Ceriodaphnia dubia, Daphnia magna, and fathead minnows). These laboratory toxicity data were then incorporated into multi-variate logistic regression equations that predict the acute toxicity of any combination of major ions. Logistic regression equations represented the toxicity data quite well, generally explaining in excess of 80 percent of the overall variance in survival. Application of the Ceriodaphnia STR to field data collected from surface waters receiving produced water discharges showed very strong correlation of STR predictions with the results of toxicity tests conducted on field-collected samples.

  14. Acute aquatic toxicity of nine alcohol ethoxylate surfactants to fathead minnow and Daphnia magna

    SciTech Connect

    Wong, D.C.L.; Dorn, P.B.; Chai, E.Y.

    1995-12-31

    The aquatic toxicity of nine commercial-grade alcohol ethoxylate surfactants was studied in acute exposures to fathead minnow (Pimephales promelas) and Daphnia magna. All studies were conducted in accordance with USEPA TSCA Good Laboratory Practice Standards. Mean measured surfactant concentrations in exposure solutions showed good agreement with nominal concentrations for both fathead minnow and daphnid tests. Surfactant recoveries ranged from 59 to 97% and 67 to 106% in the fathead minnow and daphnid solutions, respectively. The response of both species to the surfactants was generally similar with the daphnids being slightly more sensitive to a few surfactants. Surfactant toxicity tended to increase with increasing alkyl chain lengths. The effect of low average EO groups on increased surfactant toxicity was more evident in the daphnid exposures. Quantitative structure-activity relationship (QSAR) models were developed form the data which relates surfactant structure to toxicity. The models predict increasing toxicity with decreasing EO number and increasing alkyl chain length. The models also indicate that alkyl chain length has a greater effect on toxicity than EO groups. Further, the models indicate that both species did not differ markedly in their sensitivity to alkyl chain length effects, while the number of EO groups had a stronger effect on daphnids than fathead minnow. Good agreement was found between QSAR model-predicted toxicity and reported toxicity values from the literature for several surfactants previously studied.

  15. Comparative and combined acute toxicity of butachlor, imidacloprid and chlorpyrifos on earthworm, Eisenia fetida.

    PubMed

    Chen, Chen; Wang, Yanhua; Zhao, Xueping; Wang, Qiang; Qian, Yongzhong

    2014-04-01

    Various pesticides have become widespread contaminants of soils due to their large applications in agriculture and homes. An earthworm assay was used to assess the acute toxicity of butachlor, imidacloprid and chlorpyrifos with different modes of action. Ecotoxicities of these pesticides were compared for earthworm Eisenia fetida separately and in combination in artificial soil and contact filter paper tests. Imidacloprid was the most toxic for E. fetida with LC₅₀ (lethal concentration 50) values three orders magnitude lower than that of butachlor and chlorpyrifos in both tests. The toxicity of the mixtures was compared to that predicted by the concentration addition (CA) model. According to the CA model, the observed toxicities of all binary mixtures were less than additive. However, for all the mixtures in 14 d artificial soil test, and mixtures of butachlor plus chlorpyrifos and imidacloprid plus chlorpyrifos in 48 h contact filter paper test, the difference in toxicity was less than 30%, hence it was concluded that the mixtures conformed to CA. The combined effects of the pesticides in contact filter paper tests were not consistent with the results in artificial soil toxicity tests, which may be associated with the interaction of soil salts with the pesticides. The CA model provides estimates of mixture toxicity that did not markedly underestimate the measured toxicity, and therefore the CA model is the most suitable to use in ecological risk assessments of the pesticides.

  16. Acute acetaminophen toxicity in transgenic mice with elevated hepatic glutathione.

    PubMed

    Rzucidlo, S J; Bounous, D I; Jones, D P; Brackett, B G

    2000-06-01

    Previous studies demonstrated that elevation of hepatic glutathione (GSH) concentrations protect against acetaminophen (APAP) hepatotoxicity in mice. Employing transgenic mice overexpressing glutathione synthetase, this study was conducted to determine if sustained elevation of hepatic GSH concentrations could ameliorate or prevent APAP toxicity. International Cancer Research transgenic mouse males and matched (ie same strain, sex, and age) control nontransgenic mice were pretreated ip with GSH synthetase substrate gamma-glutamylcysteinyl ethyl ester (gamma-GCE) or with saline. After a 16-h fast, mice received a single dose of 500 mg APAP/kg bw in saline ip and were sacrificed 4 h later. Other mice similarly pretreated were killed without APAP challenge. The elevated GSH concentrations in transgenic mice livers did not lessen APAP hepatotoxicity. Instead higher degrees of hepatotoxicity and nephrotoxicity were observed in transgenic mice than in controls as indicated by higher serum alanine aminotransferase activity and more severe histopathological lesions in transgenic mice livers and kidneys. Pretreatment with gamma-GCE did not affect either initial or post-APAP treatment tissue GSH concentrations or observed degrees of toxicity. Detection of a higher level of serum APAP in transgenic mice and the histopathological lesions found in transgenic mice kidneys together with no observable nephrotoxicity in control mice indicated early kidney damage in transgenic mice. Our findings suggest that high levels of GSH-APAP conjugates resulting from increased GSH concentrations in the livers of transgenic mice caused rapid kidney damage. Compromised excretory ability may have caused retention of APAP, which, in effect, elicited higher hepatotoxicity than that observed in nontransgenic mice.

  17. Evaluation of Potential Oxidative Stress in Egyptian Patients with Acute Zinc Phosphide Poisoning and the Role of Vitamin C

    PubMed Central

    Sagah, Ghada A.; Oreby, Merfat M.; El-Gharbawy, Rehab M.; Ahmed Fathy, Amal S.

    2015-01-01

    Objective To evaluate potential oxidative stress in patients with acute phosphide poisoning and the effect of vitamin C. Methods Participants were females and divided into three groups; group I: healthy volunteers group II: healthy volunteers received vitamin C, group III: patients with acute phosphide poisoning received the supportive and symptomatic treatment and group IV: patients with acute phosphide poisoning received the supportive and symptomatic treatment in addition to vitamin C. All the participants were subjected to thorough history, clinical examination, ECG and laboratory investigations were carried on collected blood and gastric lavage samples on admission. Blood samples were divided into two parts, one for measurement of routine investigations and the second part was used for evaluation of malondialdehyde and total thiol levels before and after receiving the treatment regimen. Results Most of the cases in this study were among the age group of 15–25 years, females, single, secondary school education, from rural areas and suicidal. All vital signs were within normal range and the most common complaint was vomiting and abdominal pain. All cases in this study showed normal routine investigations. The mean MDA levels after receiving treatment decreased significantly in groups II and IV. The mean total thiol levels increased significantly after receiving treatment in groups II and IV. Conclusion It can be concluded that vitamin C has a potential benefit due to its antioxidant property on zinc phosphide induced-oxidative stress in acute zinc phosphide poisoned patients. PMID:26715917

  18. Influence of pH and inorganic phosphate on toxicity of zinc to Arthrobacter sp. isolated from heavy-metal-contaminated sediments.

    PubMed

    Moberly, James G; Staven, Ari; Sani, Rajesh K; Peyton, Brent M

    2010-10-01

    Because of its high solubility over a wide range of pH conditions, zinc is found in many natural and human-impacted systems. Zinc speciation is critical in assessing zinc toxicity to microorganisms because it varies considerably with pH and is dependent on other aqueous constituents. Combined results of thermodynamic modeling, statistical analysis, and batch culture studies using Arthrobacter sp. JM018 suggest that the toxic species may not be solely limited to the free ion, but also includes ZnHPO(4)(0)(aq). Cellular uptake of ZnHPO(4)(0)(aq) through the inorganic phosphate transporter (Pit family), which requires a neutral metal phosphate complex for phosphate transport, may explain the observed toxicity. Based on visual MINTEQ (v3.0) modeling, at 50 μM total zinc, ZnHPO(4)(0)(aq) constitutes 33, 70, and 76% of the neutral metal phosphate pool at pH 6, 7, and 8, respectively. At 50 μM total zinc, cultures supplied with organic phosphate (glycerol-3-phosphate) show no significant response to pH (p = 0.13) while inhibition of inorganic phosphate-supplemented cultures, whose neutral metal phosphates are increasingly dominated by ZnHPO(4)(0)(aq), show significant pH dependence (p = 9.45 × 10(-7)). Using sodium to decrease the distribution of ZnHPO(4)(0)(aq) in the neutral metal phosphate pool also decreased the pH dependent toxicity, further supporting this mechanism. These findings show the important role of minor zinc species in organism toxicity and have wider implications because the Pit inorganic phosphate transport system is widely distributed in Bacteria, Archaea, and Eukarya.

  19. Effectiveness of a propolis and zinc solution in preventing acute otitis media in children with a history of recurrent acute otitis media.

    PubMed

    Marchisio, P; Esposito, S; Bianchini, S; Desantis, C; Galeone, C; Nazzari, E; Pignataro, L; Principi, N

    2010-01-01

    Recurrent acute otitis media (rAOM) is frequently encountered in infants and children and the lack of any definitive treatment has led parents and physicians to try complementary and alternative therapies. We evaluated the efficacy of a propolis and zinc suspension in preventing AOM in 122 children aged 1-5 years with a documented history of rAOM, who were prospectively, blindly, randomized 1:1 to receive the suspension plus elimination of environmental risk factors or elimination of environmental risk factors only. AOM- and respiratory-related morbidity were assessed at study entry and every four weeks. In the 3-month treatment period AOM was diagnosed in 31 (50.8%) children given the propolis and zinc suspension and in 43 (70.5%) controls (p=0.04). The mean number of episodes of AOM per child/month was 0.23+/-0.26 in the propolis and zinc group and 0.34+/-0.29 in controls (reduction 32.0%, p=0.03). The administration of a propolis and zinc suspension to children with a history of rAOM can significantly reduce the risk of new AOM episodes and AOM-related antibiotic courses, with no problem of safety or tolerability, and with a very good degree of parental satisfaction. No effect can be expected on respiratory infections other than AOM.

  20. Acute and Subacute Oral Toxicity Evaluation of Eriobotrya japonica Leaf Triterpene Acids in ICR Mice

    PubMed Central

    Shi, Xianai

    2017-01-01

    The interest focusing on Eriobotrya japonica leaf triterpene acid (ELTA) has increased recently because of its beneficial effects on health. However, there has been a lack of experimental data on its toxicity. The present study therefore was conducted to evaluate its toxicity in ICR mice. The results showed that ELTA produced neither mortality nor toxicity of the main organs in ICR male and female mice in both acute (0.30, 0.65, 1.39, and 3.00 g·kg−1 body weight) and subacute (150, 300, and 600 mg·kg−1 BW) 28-day toxicity studies. Because of lacking apparently adverse effects found in the hematology, clinical biochemistry, and histopathology evaluation, results of the present study together with the beneficial effects make ELTA as a promising dietary supplement and indicated that ELTA administered orally might have a large safety margin for human.

  1. Nrf2-dependent protection against acute sodium arsenite toxicity in zebrafish.

    PubMed

    Fuse, Yuji; Nguyen, Vu Thanh; Kobayashi, Makoto

    2016-08-15

    Transcription factor Nrf2 induces a number of detoxifying enzymes and antioxidant proteins to confer protection against the toxic effects of a diverse range of chemicals including inorganic arsenicals. Although a number of studies using cultured cells have demonstrated that Nrf2 has a cell-protective function against acute and high-dose arsenic toxicity, there is no clear in vivo evidence of this effect. In the present study, we genetically investigated the protective role of Nrf2 against acute sodium arsenite toxicity using the zebrafish Nrf2 mutant, nrf2a(fh318). After treatment with 1mM sodium arsenite, the survival of nrf2a(fh318) larvae was significantly shorter than that of wild-type siblings, suggesting that Nrf2 protected the zebrafish larvae against high-dose arsenite exposure. To understand the molecular basis of the Nrf2-dependent protection, we analyzed the gene expression profiles after arsenite exposure, and found that the genes involved in the antioxidative function (prdx1 and gclc), arsenic metabolism (gstp1) and xenobiotic elimination (abcc2) were induced in an Nrf2-dependent manner. Furthermore, pre-treatment with sulforaphane, a well-known Nrf2 activator improved the survival of zebrafish larvae after arsenic exposure. Based on these results, we concluded that Nrf2 plays a fundamental and conserved role in protection against acute sodium arsenite toxicity.

  2. Acute and subacute toxicity evaluation of ethanolic extract from fruits of Schinus molle in rats.

    PubMed

    Ferrero, Adriana; Minetti, Alejandra; Bras, Cristina; Zanetti, Noelia

    2007-09-25

    Ethanolic and hexanic extracts from fruits and leaves of Schinus molle showed ability to control several insect pests. Potential vertebrate toxicity associated with insecticidal plants requires investigation before institutional promotion. The aim of the present study was to evaluate the acute and subacute toxicity of ethanolic extracts from fruits of Schinus molle in rats. The plant extract was added to the diet at 2g/kg body weight/day during 1 day to evaluate acute toxicity and at 1g/kg body weight/day during 14 days to evaluate subacute toxicity. At the end of the exposure and after 7 days, behavioral and functional parameters in a functional observational battery and motor activity in an open field were assessed. Finally, histopathological examinations were conducted on several organs. In both exposures, an increase in the arousal level was observed in experimental groups. Also, the landing foot splay parameter increased in the experimental group after acute exposure. Only the subacute exposure produced a significant increase in the motor activity in the open field. All these changes disappeared after 7 days. None of the exposures affected the different organs evaluated. Our results suggest that ethanolic extracts from fruits and leaves of Schinus molle should be relatively safe to use as insecticide.

  3. Assessment of acute toxicity of carbofuran in Macrobrachium olfersii (Wiegmann, 1836) at different temperature levels.

    PubMed

    Barbieri, Edison; Moreira, Priscila; Luchini, Luiz Alberto; Hidalgo, Karla Ruiz; Muñoz, Alejandro

    2016-01-01

    Carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate; C12H15NO3) is one of the most toxic carbamate pesticides. For acute toxicity of carbofuran, juveniles of Macrobrachium olfersii were exposed to different concentrations of carbofuran using the static renewal method at different temperature levels (15, 20 and 25°C) at pH 7.0. The main purpose of the present study was to detect the acute toxicity of carbofuran to M. olfersii and investigate its effects on oxygen consumption and ammonium excretion; these tests have not been carried out in this species before. First, the acute toxicity - median lethal concentration - of carbofuran to M. olfersii for 24, 48, 72 and 96 h was examined, which resulted in the following values: 1.64, 1.22, 0.86 and 0.42 mg L(-1), respectively. Furthermore, we also found that carbofuran caused an inhibition in oxygen consumption of 60.6, 65.3 and 66.2% with respect to the control. In addition, after separate exposures to carbofuran, elevations in ammonium excretion were more than 500% with respect to the control.

  4. Acute and chronic toxicity of six anticancer drugs on rotifers and crustaceans.

    PubMed

    Parrella, Alfredo; Lavorgna, Margherita; Criscuolo, Emma; Russo, Chiara; Fiumano, Vittorio; Isidori, Marina

    2014-11-01

    The growing use of cytostatic drugs is gaining relevance as an environmental concern. Environmental and distribution studies are increasing due to the development of accurate analytical methods, whereas ecotoxicological studies are still lacking. The aim of the present study was to investigate the acute and chronic toxicity of six cytostatics (5-fluorouracil, capecitabine, cisplatin, doxorubicin, etoposide, and imatinib) belonging to five classes of Anatomical Therapeutic Classification (ATC) on primary consumers of the aquatic chain (Daphnia magna, Ceriodaphnia dubia, Brachionus calyciflorus, and Thamnocephalus platyurus). Acute ecotoxicological effects occurred at concentrations in the order of mgL(-)(1), higher than those predicted in the environment, and the most acutely toxic drugs among those tested were cisplatin and doxorubicin for most aquatic organisms. For chronic toxicity, cisplatin and 5-fluorouracil showed the highest toxic potential in all test organisms, inducing 50% reproduction inhibition in crustaceans at concentrations on the order of μgL(-)(1). Rotifers were less susceptible to these pharmaceuticals. On the basis of chronic results, the low effective concentrations suggest a potential environmental risk of cytostatics. Thus, this study could be an important starting point for establishing the real environmental impact of these substances.

  5. Relative oral efficacy and acute toxicity of hydroxypyridin-4-one iron chelators in mice

    SciTech Connect

    Porter, J.B.; Morgan, J.; Hoyes, K.P.; Burke, L.C.; Huehns, E.R.; Hider, R.C. )

    1990-12-01

    The relationship between the oral efficacy and the acute toxicity of hydroxypyridin-4-one iron chelators has been investigated to clarify structure-function relationships of these compounds in vivo and to identify compounds with the maximum therapeutic safety margin. By comparing 59Fe excretion following oral or intraperitoneal administration of increasing doses of each chelator to iron-overloaded mice, the most effective compounds have been identified. These have partition coefficients (Kpart) above 0.3 in the iron-free form with a trend of increasing oral efficacy with increasing Kpart values (r = .6). However, this is achieved at a cost of increasing acute toxicity, as shown by a linear correlation between 59Fe excretion increase per unit dose and 1/LD50 (r = .83). A sharp increase in the LD50 values is observed for compounds with Kpart values above 1.0, suggesting that such compounds are unlikely to possess a sufficient therapeutic safety margin. Below a Kpart of 1.0, acute toxicity is relatively independent of lipid solubility. All the compounds are less toxic by the oral route than by the intraperitoneal route, although iron excretion is not significantly different by these two routes. At least five compounds (CP51, CP94, CP93, CP96, and CP21) are more effective orally than the same dose of intraperitoneal desferrioxamine (DFO) (P less than or equal to .02) or orally administered L1(CP20) (P less than or equal to .02).

  6. Toxicity and accumulation of zinc pyrithione in the liver and kidneys of Carassius auratus gibelio: association with P-glycoprotein expression.

    PubMed

    Ren, Tao; Fu, Gui-Hong; Liu, Teng-Fei; Hu, Kun; Li, Hao-Ran; Fang, Wen-Hong; Yang, Xian-Le

    2017-02-01

    Zinc pyrithione (ZPT) is a broad-spectrum antibacterial and antifungal agent; therefore, it is widely used in industry and civilian life. It is discharged into the aquatic environment with industrial and civilian waste water. Carassius sp. is one of the most widely distributed and farmed fish in China. The effects of aquatic ZPT on Carassius sp. remain unknown. In this study, we determined the acute toxicity of ZPT on Carassius sp. The results showed that the median lethal concentration (LC50 96 h) of ZPT on Carassius sp. cultivated in freshwater or water with 1.5 or 3 ‰ salinity was 0.163, 0.126, and 0.113 mg/L, respectively. ZPT has a higher affinity to the liver than the kidney, with a prolonged tissue residual time. P-glycoprotein (P-gp), an ATP-binding cassette transporter, was found to be induced in the liver and kidney tissues of these Carassius spp. after ZPT treatment, based on the determination of its mRNA and protein levels by quantitative real-time reverse transcription polymerase chain reaction and immunohistochemistry, respectively. The ZPT accumulation and magnitude of P-gp induction were also affected by the salinity of the cultivation water. These results suggest that aquatic ZPT is potentially toxic to Carassius sp. We speculate that P-gp induction may play a protective role for Carassius sp. Our findings provide a basis for assessing the potential risk of ZPT to aquatic animals including Carassius sp.

  7. Intensity-Modulated Radiation Therapy Significantly Improves Acute Gastrointestinal Toxicity in Pancreatic and Ampullary Cancers

    SciTech Connect

    Yovino, Susannah; Poppe, Matthew; Jabbour, Salma; David, Vera; Garofalo, Michael; Pandya, Naimesh; Alexander, Richard; Hanna, Nader; Regine, William F.

    2011-01-01

    Purpose: Among patients with upper abdominal malignancies, intensity-modulated radiation therapy (IMRT) can improve dose distributions to critical dose-limiting structures near the target. Whether these improved dose distributions are associated with decreased toxicity when compared with conventional three-dimensional treatment remains a subject of investigation. Methods and Materials: 46 patients with pancreatic/ampullary cancer were treated with concurrent chemoradiation (CRT) using inverse-planned IMRT. All patients received CRT based on 5-fluorouracil in a schema similar to Radiation Therapy Oncology Group (RTOG) 97-04. Rates of acute gastrointestinal (GI) toxicity for this series of IMRT-treated patients were compared with those from RTOG 97-04, where all patients were treated with three-dimensional conformal techniques. Chi-square analysis was used to determine if there was a statistically different incidence in acute GI toxicity between these two groups of patients. Results: The overall incidence of Grade 3-4 acute GI toxicity was low in patients receiving IMRT-based CRT. When compared with patients who had three-dimensional treatment planning (RTOG 97-04), IMRT significantly reduced the incidence of Grade 3-4 nausea and vomiting (0% vs. 11%, p = 0.024) and diarrhea (3% vs. 18%, p = 0.017). There was no significant difference in the incidence of Grade 3-4 weight loss between the two groups of patients. Conclusions: IMRT is associated with a statistically significant decrease in acute upper and lower GI toxicity among patients treated with CRT for pancreatic/ampullary cancers. Future clinical trials plan to incorporate the use of IMRT, given that it remains a subject of active investigation.

  8. Acute and chronic toxicity of the benzoylurea pesticide, lufenuron, in the fish, Colossoma macropomum.

    PubMed

    Rafaela Leão Soares, Priscila; Lucas Corrêa de Andrade, André; Pinheiro Santos, Thamiris; Caroline Barros Lucas da Silva, Stephannie; Freitas da Silva, Jadson; Rodrigues Dos Santos, Amanda; Hugo Lima da Silva Souza, Elton; Magliano da Cunha, Franklin; Wanderley Teixeira, Valéria; Sales Cadena, Marilia Ribeiro; Bezerra de Sá, Fabrício; Bezerra de Carvalho Júnior, Luiz; Gonçalves Cadena, Pabyton

    2016-10-01

    Lufenuron is a benzoylurea insecticide that interfere in chitin synthesis in insects. Although lufenuron is widely used in agriculture and aquaculture, rare are studies described that relates to possible toxic effects in fish. This work aimed to evaluate acute and chronic toxic effects of benzoylurea pesticide (lufenuron) on biological parameters of Colossoma macropomum (Tambaqui). In the acute test, juveniles of Tambaqui were divided into control group and five experimental groups with exposure from 0.1 to 0.9 mg/L of lufenuron for 96 h. Animals were also submitted to chronic toxicity test for four months in concentrations of 0.1 and 0.3 mg/L of lufenuron, the concentration used in the treatment of ectoparasites in fish and 50% of LC50 96 h, respectively. The presence of hemorrhages was observed in eyes, fins and operculum of fish exposed to 0.7 and 0.9 mg/L of lufenuron. Histological analysis showed changes in the morphology of fish gills submitted to acute toxicity test, as lamellar aneurysm and blood congestion inside lamellae. Lufenuron promoted damage in fish retina as in ability to respond to stimuli in photoreceptors and in ON-bipolar cells in acute test. In chronic test, blood glucose analysis and morphometric parameters showed no significant differences (p > 0.05). In general, Tambaqui exhibited behaviors associated with stress when exposed to lufenuron. Thus, lufenuron showed several toxic effects in relation to biological parameters in Tambaqui. This concerns about the use and discard of lufenuron, and indicates the requirement of environmental actions to prevent potential contamination of aquatic biota.

  9. Estimation of acute oral toxicity in rat using local lazy learning

    PubMed Central

    2014-01-01

    Background Acute toxicity means the ability of a substance to cause adverse effects within a short period following dosing or exposure, which is usually the first step in the toxicological investigations of unknown substances. The median lethal dose, LD50, is frequently used as a general indicator of a substance’s acute toxicity, and there is a high demand on developing non-animal-based prediction of LD50. Unfortunately, it is difficult to accurately predict compound LD50 using a single QSAR model, because the acute toxicity may involve complex mechanisms and multiple biochemical processes. Results In this study, we reported the use of local lazy learning (LLL) methods, which could capture subtle local structure-toxicity relationships around each query compound, to develop LD50 prediction models: (a) local lazy regression (LLR): a linear regression model built using k neighbors; (b) SA: the arithmetical mean of the activities of k nearest neighbors; (c) SR: the weighted mean of the activities of k nearest neighbors; (d) GP: the projection point of the compound on the line defined by its two nearest neighbors. We defined the applicability domain (AD) to decide to what an extent and under what circumstances the prediction is reliable. In the end, we developed a consensus model based on the predicted values of individual LLL models, yielding correlation coefficients R2 of 0.712 on a test set containing 2,896 compounds. Conclusion Encouraged by the promising results, we expect that our consensus LLL model of LD50 would become a useful tool for predicting acute toxicity. All models developed in this study are available via http://www.dddc.ac.cn/admetus. PMID:24959207

  10. Acute toxicity of mixture of acetaminophen and ibuprofen to Green Neon Shrimp, Neocaridina denticulate.

    PubMed

    Sung, Hung-Hung; Chiu, Yuh-Wen; Wang, Shu-Yin; Chen, Chien-Min; Huang, Da-Ji

    2014-07-01

    In recent years, numerous studies have indicated that various long-term use drugs, such as antibiotics or analgesics, not only cannot be completely decomposed via sewage treatment but also exhibit biological toxicity if they enter the environment; thus, the release of these drugs into the environment can damage ecological systems. This study sought to investigate the acute toxicity of two commonly utilized analgesics, ibuprofen (IBU) and acetaminophen (APAP), to aquatic organisms after these drugs have entered the water. To address this objective, the acute toxicity (median lethal concentration, LC₅₀, for a 96-h exposure) of IBU alone, APAP alone, and mixtures containing different ratios of IBU and APAP in green neon shrimp (Neocaridina denticulata) were measured. The results of four tests revealed that the 96-h LC₅₀ values for IBU and APAP alone were 6.07 mg/L and 6.60 mg/L, respectively. The 96-h LC₅₀ for a 1:1 mixture of IBU and APAP was 6.23 mg/L, and the toxicity of this mixture did not significantly differ from the toxicity of either drug alone (p<0.05). The experimental results for mixtures containing unequal ratios of IBU and APAP indicated that mixtures with high APAP concentrations and low IBU concentrations exhibited markedly greater toxicity in N. denticulata (LC₅₀=4.78 mg/L) than APAP or IBU alone. However, mixtures with high IBU concentrations and low APAP concentrations exhibited lower toxicity in N. denticulata (LC₅₀=6.78 mg/L) than IBU or APAP alone. This study demonstrated that different mixtures of IBU and APAP were associated with different toxic effects in green neon shrimp.

  11. [Acute toxicity by methotrexate used for abortion purpose. Case report].

    PubMed

    Estrada-Altamirano, Ariel; Chacón-Solís, Rogerio Armando; Hernández-Pacheco, José Antonio; Belmont-Gómez, Aurora; Valenzuela-Jirón, Arlen; Carvajal-Valencia, Javier Andrés; Maya-Quiñones, José Luis

    2011-01-01

    We report the case of a 16 years old female patient, with a pregnancy history of 11.4 weeks by ultrasound and intrauterine fetal death. In a private clinic were prescribed methotrexate 500 mg intramuscular single dose, and vaginal misoprostol. She had a clinical feature of five days of evolution characterized by fever of 39 degrees C, nausea, general attack and vomiting. The initial diagnosis was severe sepsis secondary to septic abortion, oral candidiasis and acute poisoning by methotrexate. After that, she was referred to the Instituto Nacional de Perinatologia, where stayed with fever for four days, and was managed with hydration, antibiotics, folinic acid and alkalizing. Her recovery was gradual. She was discharged after 12 days with significant clinical improvement. The literature review describes that the use of methotrexate for abortion purpose with therapeutic-dose presents a similar adverse effects to those found in our patient, however there are no case reports that describe the use of this drug in macrodosis for the same purpose, and their cytotoxic effects. We present this case because the patient used a macrodosis of this antimetabolite and due to the premature and empirical management with folinic acid, joined with alkalinization of urine, is the ideal treatment and as it is illustrated in our case.

  12. Acute oral toxicity of sodium cyanide in birds

    USGS Publications Warehouse

    Wiemeyer, Stanley N.; Hill, E.F.; Carpenter, J.W.; Krynitsky, A.J.

    1986-01-01

    Sensitivities of six avian species, black vulture (Coragyps atratus), American kestrel (Falco sparverius), Japanese quail (Coturnix japonica), domestic chicken (Gallus domesticus), eastern screech-owl (Otus asio), and European starling (Sturnus vulgaris), to acute poisoning by sodium cyanide (NaCN) were compared by single dose LD50's. Three species, domestic chickens, black vultures, and turkey vultures (Cathartes aura), were dosed with NaCN to determine cyanide residues in those that died and also in survivors, in addition to postmortem fate. Three flesh-eating species (black vulture, American kestrel, and eastern screech-owl; LD50's 4.0-8.6 mg/kg) were more sensitive to NaCN than three species (Japanese quail, domestic chicken, and European starling; LD50's 9.4-21 mg/kg) that fed predominantly on plant material. Elevated concentrations of cyanide were found in the blood of birds that died of cyanide poisoning; however, concentrations in birds that died overlapped those in survivors. Blood was superior to liver as the tissue of choice for detecting cyanide exposure. No gross pathological changes related to dosing were observed at necropsy.

  13. Antidotal treatment of the acute cardiovascular toxicity of verapamil.

    PubMed

    Strubelt, O

    1984-09-01

    Rats anaesthetized with pentobarbital and ventilated artificially were infused with 0.15 mg/kg/min. verapamil; without antidotal treatment, they died after 51.1+/-7.1 min. The survival time more than trebled upon an additional infusion with calcium chloride, epinephrine, isoprenaline, orciprenaline or prenalterol and nearly doubled upon administration of a plasma expander. It was not increased, however, by treatment with angiotensin or atropine. The infusion of verapamil declined the arterial blood pressure by 75%, and heart rate, cardiac output and peripheral resistance by about 50%; in the ECG, sinus bradycardia followed by AV-dissociation with nodal rhythm occurred. All antidotes that raised the lethal dose of verapamil increased the cardiac output. Calcium and the sympathomimetics with alpha-adrenergic activity also counteracted the verapamil-induced hypotension. Calcium did not influence the ECG alterations produced by verapamil, while the sympathomimetics restored the sinus rhythm or accelerated the nodal pacemaker. Calcium, epinephrine and isoprenaline also antagonized the strong decrease of left-ventricular dp/dt max. induced by verapamil. In conclusion, calcium as well as sympathomimetic amines are potent antidotes against the cardiovascular toxicity of verapamil, the latter being superior to calcium in their ability to improve pacemaker activity and AV-conduction.

  14. Acute ecological toxicity and environmental persistence of simulants

    SciTech Connect

    Cataldo, D.A.; Ligotke, M.W.; McVeety, B.D.; Fellows, R.J.; Bolton, H. Jr.; Li, S.W.; Van Voris, P.; Wentsel, R.S.

    1988-06-01

    The objectives of these studies are to establish the comparative environmental behavior and chemical fate of chemical simulants. Laboratory studies were undertaken to establish: (1) deposition efficiency (deposition velocities, Vd) for receptor surfaces including plant foliage and soils; (2) dose/response relationships for important environmental components including plants and soil microflora; and (3) the environmental persistence of the simulants. Chemical agent simulants are employed for a range of testing and training activities where use of chemical agents is less than suitable from a safety and environmental standpoint. A variety of chemical simulant materials are used to simulate either nerve agents or blister agents. The following research describes the environmental effects and persistence of four simulants. These are the nerve agent stimulants diisopropyl methylphosphonate (DIMP), diisopropyl fluorophosphate (DFP), and bis (2-ethylhexyl) phosphonate (BIS), and the mustard stimulant 2-chloroethyl ethyl sulfide (CEES). The vapor pressures for DIMP, DFP, and CEES are relatively high, reported to be 0.17, 0.58 and 3.4 mm Hg, respectively; while that of BIS is substantially less at 5.8 /times/ 10/sup /minus/5/ mm Hg at 25/degree/C. The chemical characteristics of DFP and CEES are very similar to G/VX-agents and mustard, respectively, and are employed for materials evaluation under controlled conditions. However, their toxicity precludes their use in the environment. DIMP and BIS are currently used for testing in the open air. 3 figs., 3 tabs.

  15. Iron sulfide attenuates the methanogenic toxicity of elemental copper and zinc oxide nanoparticles and their soluble metal ion analogs.

    PubMed

    Gonzalez-Estrella, Jorge; Gallagher, Sara; Sierra-Alvarez, Reyes; Field, Jim A

    2016-04-01

    Elemental copper (Cu(0)) and zinc oxide (ZnO) nanoparticle (NP) toxicity to methanogens has been attributed to the release of soluble metal ions. Iron sulfide (FeS) partially controls the soluble concentration of heavy metals and their toxicity in aquatic environments. Heavy metals displace the Fe from FeS forming poorly soluble metal sulfides in the FeS matrix. Therefore, FeS may be expected to attenuate the NP toxicity. This work assessed FeS as an attenuator of the methanogenic toxicity of Cu(0) and ZnO NPs and their soluble salt analogs. The toxicity attenuation capacity of fine (25-75μm) and coarse (500 to 1200μm) preparations of FeS (FeS-f and FeS-c respectively) was tested in the presence of highly inhibitory concentrations of CuCl2, ZnCl2 Cu(0) and ZnO NPs. FeS-f attenuated methanogenic toxicity better than FeS-c. The results revealed that 2.5× less FeS-f than FeS-c was required to recover the methanogenic activity to 50% (activity normalized to uninhibited controls). The results also indicated that a molar FeS-f/Cu(0) NP, FeS-f/ZnO NP, FeS-f/ZnCl2, and FeS-f/CuCl2 ratio of 2.14, 2.14, 4.28, and 8.56 respectively, was necessary to recover the methanogenic activity to >75%. Displacement experiments demonstrated that CuCl2 and ZnCl2 partially displaced Fe from FeS. As a whole, the results indicate that not all the sulfide in FeS was readily available to react with the soluble Cu and Zn ions which may explain the need for a large stoichiometric excess of FeS to highly attenuate Cu and Zn toxicity. Overall, this study provides evidence that FeS attenuates the toxicity caused by Cu(0) and ZnO NPs and their soluble ion analogs to methanogens.

  16. Iron Sulfide Attenuates the Methanogenic Toxicity of Elemental Copper and Zinc Oxide Nanoparticles and their Soluble Metal Ion Analogs

    PubMed Central

    Gonzalez-Estrella, Jorge; Gallagher, Sara; Sierra-Alvarez, Reyes; Field, Jim A.

    2016-01-01

    Elemental copper (Cu0) and zinc oxide (ZnO) nanoparticle (NP) toxicity to methanogens has been attributed to the release of soluble metal ions. Iron sulfide (FeS) partially controls the soluble concentration of heavy metals and their toxicity in aquatic environments. Heavy metals displace the Fe from FeS forming poorly soluble metal sulfides in the FeS matrix. Therefore, FeS may be expected to attenuate the NP toxicity. This work assessed FeS as an attenuator of the methanogenic toxicity of Cu0 and ZnO NPs and their soluble salt analogs. The toxicity attenuation capacity of fine (25–75 µm) and coarse (500 to 1200 µm) preparations of FeS (FeS-f and FeS-c respectively) was tested in the presence of highly inhibitory concentrations of CuCl2, ZnCl2 Cu0 and ZnO NPs. FeS-f attenuated methanogenic toxicity better than FeS-c. The results revealed that 2.5× less FeS-f than FeS-c was required to recover the methanogenic activity to 50% (activity normalized to uninhibited controls). The results also indicated that a molar FeS-f/Cu0 NP, FeS-f/ZnO NP, FeS-f/ZnCl2, and FeS-f/CuCl2 ratio of 2.14, 2.14, 4.28, and 8.56 respectively, was necessary to recover the methanogenic activity to >75%. Displacement experiments demonstrated that CuCl2 and ZnCl2 partially displaced Fe from FeS. As a whole, the results indicate that not all the sulfide in FeS was readily available to react with the soluble Cu and Zn ions which may explain the need for a large stoichiometric excesses of FeS to highly attenuate Cu and Zn toxicity. Overall, this study provides evidence that FeS attenuates the toxicity caused by Cu0 and ZnO NPs and their soluble ion analogs to methanogens. PMID:26803736

  17. Silicon (Si) alleviates cotton (Gossypium hirsutum L.) from zinc (Zn) toxicity stress by limiting Zn uptake and oxidative damage.

    PubMed

    Anwaar, Shad Ali; Ali, Shafaqat; Ali, Skhawat; Ishaque, Wajid; Farid, Mujahid; Farooq, Muhammad Ahsan; Najeeb, Ullah; Abbas, Farhat; Sharif, Muhammad

    2015-03-01

    Silicon (Si) is as an important fertilizer element, which has been found effective in enhancing plant tolerance to variety of biotic and a-biotic stresses. This study investigates the Si potential to alleviate zinc (Zn) toxicity stress in cotton (Gossypium hirsutum L.). Cotton plants were grown in hydroponics and exposed to different Zn concentration, 0, 25, and 50 μM, alone and/or in combination with 1 mM Si. Incremental Zn concentration in growth media instigated the cellular oxidative damage that was evident from elevated levels of hydrogen peroxide (H2O2), electrolyte leakage, and malondialdehyde (MDA) and consequently inhibited cotton growth, biomass, chlorophyll pigments, and photosynthetic process. Application of Si significantly suppressed Zn accumulation in various plant parts, i.e., roots, stems, and leaves and thus promoted biomass, photosynthetic, growth parameters, and antioxidant enzymes activity of Zn-stressed as well unstressed plants. In addition, Si reduced the MDA and H2O2 production and electrolyte leakage suggesting its role in protecting cotton plants from Zn toxicity-induced oxidative damage. Thus, the study indicated that exogenous Si application could improve growth and development of cotton crop experiencing Zn toxicity stress by limiting Zn bioavailability and oxidative damage.

  18. Synergistic toxic effects of zinc pyrithione and copper to three marine species: Implications on setting appropriate water quality criteria.

    PubMed

    Bao, Vivien W W; Leung, Kenneth M Y; Kwok, Kevin W H; Zhang, Amy Q; Lui, Gilbert C S

    2008-01-01

    Zinc pyrithione (ZnPT) is widely applied in conjunction with copper (Cu) in antifouling paints as a substitute for tributyltin. The combined effects of ZnPT and Cu on marine organisms, however, have not been fully investigated. This study examined the toxicities of ZnPT alone and in combination with Cu to the diatom Thalassiosira pseudonana, polychaete larvae Hydroides elegans and amphipod Elasmopus rapax. Importantly, ZnPT and Cu resulted in a strong synergistic effect with isobologram interaction parameter lambda>1 for all test species. The combined toxicity of ZnPT and Cu was successfully modelled using the non-parametric response surface and its contour. Such synergistic effects may be partly due to the formation of copper pyrithione. It is, therefore, inadequate to assess the ecological risk of ZnPT to marine organisms solely based on the toxicity data generated from the biocide alone. To better protect precious marine resources, it is advocated to develop appropriate water quality criteria for ZnPT with the consideration of its compelling synergistic effects with Cu at environmentally realistic concentrations.

  19. Reduced Acute Bowel Toxicity in Patients Treated With Intensity-Modulated Radiotherapy for Rectal Cancer

    SciTech Connect

    Samuelian, Jason M.; Callister, Matthew D.; Ashman, Jonathan B.; Young-Fadok, Tonia M.; Borad, Mitesh J.; Gunderson, Leonard L.

    2012-04-01

    Purpose: We have previously shown that intensity-modulated radiotherapy (IMRT) can reduce dose to small bowel, bladder, and bone marrow compared with three-field conventional radiotherapy (CRT) technique in the treatment of rectal cancer. The purpose of this study was to review our experience using IMRT to treat rectal cancer and report patient clinical outcomes. Methods and Materials: A retrospective review was conducted of patients with rectal cancer who were treated at Mayo Clinic Arizona with pelvic radiotherapy (RT). Data regarding patient and tumor characteristics, treatment, acute toxicity according to the Common Terminology Criteria for Adverse Events v 3.0, tumor response, and perioperative morbidity were collected. Results: From 2004 to August 2009, 92 consecutive patients were treated. Sixty-one (66%) patients were treated with CRT, and 31 (34%) patients were treated with IMRT. All but 2 patients received concurrent chemotherapy. There was no significant difference in median dose (50.4 Gy, CRT; 50 Gy, IMRT), preoperative vs. postoperative treatment, type of concurrent chemotherapy, or history of previous pelvic RT between the CRT and IMRT patient groups. Patients who received IMRT had significantly less gastrointestinal (GI) toxicity. Sixty-two percent of patients undergoing CRT experienced {>=}Grade 2 acute GI side effects, compared with 32% among IMRT patients (p = 0.006). The reduction in overall GI toxicity was attributable to fewer symptoms from the lower GI tract. Among CRT patients, {>=}Grade 2 diarrhea and enteritis was experienced among 48% and 30% of patients, respectively, compared with 23% (p = 0.02) and 10% (p = 0.015) among IMRT patients. There was no significant difference in hematologic or genitourinary acute toxicity between groups. In addition, pathologic complete response rates and postoperative morbidity between treatment groups did not differ significantly. Conclusions: In the management of rectal cancer, IMRT is associated with a

  20. Assessing contaminant sensitivity of endangered and threatened aquatic species: Part I. Acute toxicity of five chemicals

    USGS Publications Warehouse

    Dwyer, F.J.; Mayer, F.L.; Sappington, L.C.; Buckler, D.R.; Bridges, C.M.; Greer, I.E.; Hardesty, D.K.; Henke, C.E.; Ingersoll, C.G.; Kunz, J.L.; Whites, D.W.; Augspurger, T.; Mount, D.R.; Hattala, K.; Neuderfer, G.N.

    2005-01-01

    Assessment of contaminant impacts to federally identified endangered, threatened and candidate, and state-identified endangered species (collectively referred to as "listed" species) requires understanding of a species' sensitivities to particular chemicals. The most direct approach would be to determine the sensitivity of a listed species to a particular contaminant or perturbation. An indirect approach for aquatic species would be application of toxicity data obtained from standard test procedures and species commonly used in laboratory toxicity tests. Common test species (fathead minnow, Pimephales promelas; sheepshead minnow, Cyprinodon variegatus; and rainbow trout, Oncorhynchus mykiss) and 17 listed or closely related species were tested in acute 96-hour water exposures with five chemicals (carbaryl, copper, 4-nonylphenol, pentachlorophenol, and permethrin) representing a broad range of toxic modes of action. No single species was the most sensitive to all chemicals. For the three standard test species evaluated, the rainbow trout was more sensitive than either the fathead minnow or sheepshead minnow and was equal to or more sensitive than listed and related species 81% of the time. To estimate an LC50 for a listed species, a factor of 0.63 can be applied to the geometric mean LC50 of rainbow trout toxicity data, and more conservative factors can be determined using variance estimates (0.46 based on 1 SD of the mean and 0.33 based on 2 SD of the mean). Additionally, a low- or no-acute effect concentration can be estimated by multiplying the respective LC50 by a factor of approximately 0.56, which supports the United States Environmental Protection Agency approach of multiplying the final acute value by 0.5 (division by 2). When captive or locally abundant populations of listed fish are available, consideration should be given to direct testing. When direct toxicity testing cannot be performed, approaches for developing protective measures using common test

  1. Assessing contaminant sensitivity of endangered and threatened aquatic species: part I. Acute toxicity of five chemicals.

    PubMed

    Dwyer, F J; Mayer, F L; Sappington, L C; Buckler, D R; Bridges, C M; Greer, I E; Hardesty, D K; Henke, C E; Ingersoll, C G; Kunz, J L; Whites, D W; Augspurger, T; Mount, D R; Hattala, K; Neuderfer, G N

    2005-02-01

    Assessment of contaminant impacts to federally identified endangered, threatened and candidate, and state-identified endangered species (collectively referred to as "listed" species) requires understanding of a species' sensitivities to particular chemicals. The most direct approach would be to determine the sensitivity of a listed species to a particular contaminant or perturbation. An indirect approach for aquatic species would be application of toxicity data obtained from standard test procedures and species commonly used in laboratory toxicity tests. Common test species (fathead minnow, Pimephales promelas; sheepshead minnow, Cyprinodon variegatus; and rainbow trout, Oncorhynchus mykiss) and 17 listed or closely related species were tested in acute 96-hour water exposures with five chemicals (carbaryl, copper, 4-nonylphenol, pentachlorophenol, and permethrin) representing a broad range of toxic modes of action. No single species was the most sensitive to all chemicals. For the three standard test species evaluated, the rainbow trout was more sensitive than either the fathead minnow or sheepshead minnow and was equal to or more sensitive than listed and related species 81% of the time. To estimate an LC50 for a listed species, a factor of 0.63 can be applied to the geometric mean LC50 of rainbow trout toxicity data, and more conservative factors can be determined using variance estimates (0.46 based on 1 SD of the mean and 0.33 based on 2 SD of the mean). Additionally, a low- or no-acute effect concentration can be estimated by multiplying the respective LC50 by a factor of approximately 0.56, which supports the United States Environmental Protection Agency approach of multiplying the final acute value by 0.5 (division by 2). When captive or locally abundant populations of listed fish are available, consideration should be given to direct testing. When direct toxicity testing cannot be performed, approaches for developing protective measures using common test

  2. Fish acute toxicity syndromes and their use in the QSAR approach to hazard assessment

    SciTech Connect

    McKim, J.M.; Bradbury, S.P.; Niemi, G.J.

    1987-04-01

    Implementation of the Toxic Substances Control Act of 1977 creates the need to reliably establish testing priorities because laboratory resources are limited and the number of industrial chemicals requiring evaluation is overwhelming. The use of quantitative structure activity relationship (QSAR) models as rapid and predictive screening tools to select more potentially hazardous chemicals for in-depth laboratory evaluation has been proposed. Further implementation and refinement of quantitative structure-toxicity relationships in aqueous toxicology and hazard assessment requires the development of a mode-of-action database. With such a database, a qualitative structure-activity relationship can be formulated to assign the proper mode of action, and respective QSAR, to a given chemical structure. In this review, the development of fish acute toxicity syndromes (FATS), which are toxic-response sets based on various behavioral and physiological-biochemical measurements, and their projected use in the mode-of-action database are outlined. Using behavioral parameters monitored in the fathead minnow during acute toxicity testing, FATS associated with acetylcholinesterase (AChE) inhibitors and narcotics could be reliably predicted. However, compounds classified as oxidative phosphorylation uncouplers or stimulants could not be resolved. Refinement of this approach by using respiratory-cardiovascular responses in the rainbow trout, enabled FATS associated with AChE inhibitors, convulsants, narcotics, respiratory blockers, respiratory membrane irritants, and uncouplers to be correctly predicted.

  3. Acute toxicity of live and decomposing green alga Ulva ( Enteromorpha) prolifera to abalone Haliotis discus hannai

    NASA Astrophysics Data System (ADS)

    Wang, Chao; Yu, Rencheng; Zhou, Mingjiang

    2011-05-01

    From 2007 to 2009, large-scale blooms of green algae (the so-called "green tides") occurred every summer in the Yellow Sea, China. In June 2008, huge amounts of floating green algae accumulated along the coast of Qingdao and led to mass mortality of cultured abalone and sea cucumber. However, the mechanism for the mass mortality of cultured animals remains undetermined. This study examined the toxic effects of Ulva ( Enteromorpha) prolifera, the causative species of green tides in the Yellow Sea during the last three years. The acute toxicity of fresh culture medium and decomposing algal effluent of U. prolifera to the cultured abalone Haliotis discus hannai were tested. It was found that both fresh culture medium and decomposing algal effluent had toxic effects to abalone, and decomposing algal effluent was more toxic than fresh culture medium. The acute toxicity of decomposing algal effluent could be attributed to the ammonia and sulfide presented in the effluent, as well as the hypoxia caused by the decomposition process.

  4. Acute toxicity of eight oil spill response chemicals to temperate, boreal, and Arctic species.

    PubMed

    Hansen, Bjørn Henrik; Altin, Dag; Bonaunet, Kristin; Overjordet, Ida Beathe

    2014-01-01

    The objectives of this study were to (1) determine the acute toxicity of selected shoreline washing agents (SWA) and dispersants, and (2) assess interspecies differences in sensitivity to the products. Eight shoreline washing agents (Hela saneringsvæske, Bios, Bioversal, Absorrep K212, and Corexit 9580) and chemical dispersants (Corexit 9500, Dasic NS, and Gamlen OD4000) were tested on five marine species, algae Skeletonema costatum, planktonic copepod species Acartia tonsa (temperate species), Calanus finmarchicus (boreal species) and Calanus glacialis (Arctic species), and benthic amphipod Corophium volutator. For most products, A. tonsa was the most sensitive species, whereas C. volutator was the least sensitive; however, these species were exposed through different media (water/sediment). In general, all copepod species displayed a relatively similar sensitivity to all products. However, A. tonsa was somewhat more sensitive than other copepods to most of the tested products. Thus, A. tonsa appears to be a candidate species for boreal and Arctic copepods for acute toxicity testing, and data generated on this species may be used as to provide conservative estimates. The benthic species (C. volutator) had a different sensitivity pattern relative to pelagic species, displaying higher sensitivity to solvent-based SWA than to water-based SWA. Comparing product toxicity, the dispersants were in general most toxic while the solvent-based SWA were least toxic to pelagic species.

  5. Fish acute toxicity syndromes and their use in the QSAR approach to hazard assessment.

    PubMed Central

    McKim, J M; Bradbury, S P; Niemi, G J

    1987-01-01

    Implementation of the Toxic Substances Control Act of 1977 creates the need to reliably establish testing priorities because laboratory resources are limited and the number of industrial chemicals requiring evaluation is overwhelming. The use of quantitative structure activity relationship (QSAR) models as rapid and predictive screening tools to select more potentially hazardous chemicals for in-depth laboratory evaluation has been proposed. Further implementation and refinement of quantitative structure-toxicity relationships in aquatic toxicology and hazard assessment requires the development of a "mode-of-action" database. With such a database, a qualitative structure-activity relationship can be formulated to assign the proper mode of action, and respective QSAR, to a given chemical structure. In this review, the development of fish acute toxicity syndromes (FATS), which are toxic-response sets based on various behavioral and physiological-biochemical measurements, and their projected use in the mode-of-action database are outlined. Using behavioral parameters monitored in the fathead minnow during acute toxicity testing, FATS associated with acetylcholinesterase (AChE) inhibitors and narcotics could be reliably predicted. However, compounds classified as oxidative phosphorylation uncouplers or stimulants could not be resolved. Refinement of this approach by using respiratory-cardiovascular responses in the rainbow trout, enabled FATS associated with AChE inhibitors, convulsants, narcotics, respiratory blockers, respiratory membrane irritants, and uncouplers to be correctly predicted. PMID:3297660

  6. Acute and subchronic (13-week) toxicity of fermented Acanthopanax koreanum extracts in Sprague Dawley rats.

    PubMed

    Cho, MyoungLae; Shin, Gi-Hae; Kim, Jae-Min; Lee, Jin-Ha; Park, Sun-Ok; Lee, Sang-Jong; Shin, HyunMu; Lee, Boo-Yong; Kang, Il-Jun; Lee, Ok-Hwan

    2016-06-01

    The biological fermentation of plants is usually used to improve their product properties, including their biological activity. Acanthopanax koreanum is a plant indigenous to Jeju, Korea; however, fermented A. koreanum (FAK) has not been guaranteed to be safe. Therefore, in this study, a safety evaluation of aqueous extracts of FAK was performed using Sprague Dawley rats. The acute toxicity of FAK did not influence animal mortality, body weight changes or the animals' clinical appearance at a concentration of 5000 mg/kg body weight. Using doses of 500, 1000 and 2000 mg/kg/day in a subchronic (13-week) toxicity study, the administration of FAK in male rats increased their body weight, food consumption, absolute liver weight, liver-associated enzymes and total cholesterol content. However, these effects of FAK were not considered toxic because the changes were not accompanied by any evidence of clinical signs or any change in the histopathological examination. On the other hand, the FAK-treated female rats did not exhibit significant changes in their body weight, food consumption, absolute and relative organ weights or liver enzymes. These results suggest that the acute oral administration of FAK is non-toxic to rats, and 13 weeks of repeated dosing demonstrated no FAK-related toxicity at a concentration of 2000 mg/kg. Therefore, the no-observed-adverse-effect level (NOAEL) of FAK was determined to be 2000 mg/kg/day for both male and female rats.

  7. Effect of sulfate concentration on acute toxicity of selenite and selenate to invertebrates and fish. Final report

    SciTech Connect

    McIntyre, D.O.; McCauley, D.J.; McCool, P.; Winkler, N.; DeGraeve, M.

    1998-12-01

    The effect of sulfate concentration on the acute toxicity of selenite (Se IV) and selenate (Se VI) to freshwater organisms was evaluated using toxicity test data generated from this study and toxicity data obtained from the open literature. The acute toxicity of Se IV and Se VI to fathead minnows and two amphipod species, Gammarus pseudolimnaeus and Hyalella azteca, were determined in four different sulfate concentrations. The newly generated toxicity data combined with the data obtained from the literature were evaluated using analysis of covariance to determine if there was a significant relationship between acute toxicity and sulfate concentration. The analysis of the Se IV data indicated that there was not a significant relationship between the acute toxicity of Se IV and sulfate concentration. A significant relationship was found between the acute toxicity of Se VI to freshwater organisms and sulfate concentration. Statistically significant slopes describing the relationship between Se VI toxicity and sulfate concentration were determined for individual species and for the combined data. A sulfate-based equation was constructed using the pooled slope to modify the criterion maximum concentration (CMC) for selenate: CMC = e{sup [0.4259(ln[sulfate]) + 4.6305]}.

  8. Acute toxicity of cadmium and sodium pentachlorophenate to daphnids and fish

    SciTech Connect

    Hall, W.S.; Paulson, R.L.; Hall, L.W. Jr.; Burton, D.T.

    1986-08-01

    When estimating the toxicity of effluents it is desirable to use organisms sensitive to a wide range of pollutants. Currently, the US Environmental Protection Agency (US EPA) recommends the use of Daphnia pulex, Daphnia magna, and Pimephales promelas to assess the toxicity of freshwater effluents. Ceriodaphnia sp. has also received increased attention as a standard toxicity test organism due to its sensitivity, short generation time, and ubiquitous distribution. Comparison of toxicity data generated by different investigators is often difficult because of differences in test procedures, dilution waters, or nutritional history of test organisms. The primary objectives of this research were to compare the sensitivity of Daphnia magna, Daphnia pulex, Ceriodaphnia reticulata, and Pimephales promelas to the reference toxicants CdCl/sub 2/ and sodium pentachlorophenate (NaPCP) and to compare results with those obtained by other investigators. A secondary objective of this study was to evaluate the effect of different dilution waters on the acute toxicity of these reference toxicants to the above test organisms.

  9. Acute Dermal Toxicity of CHF1, CHR2 and Saline in Rabbits.

    DTIC Science & Technology

    1982-09-01

    yellowish-white foci in the liv*-r that are typical (f lecions caused by Eimeria stiedae , a coccidia that infects in-rahentic bile ducts of rabbits . Thene...AD-A12i 944 ACUTE DERI1ALTTOXICITY OF CHFi CHR2 AND SALINE IN / RABBITS (U) LETTERMAN ARMY INST OF RESEARCH PRESIDIO OF SAN FRANCISCO CA M A HANES ET...NdATIONiAL 3SPIA OF SITiOAM - 963 -A - INSTITUTE REPORT NO. 130 S ACUTE DERMAL TOXICITY OF CHF 1, CHR 2 AND SALINE IN RABBITS MARTHA A. HANES, DVM, CPT VC JOHN

  10. Acute and chronic toxicity of buprofezin on Daphnia magna and the recovery evaluation.

    PubMed

    Liu, Yong; Qi, Suzhen; Zhang, Wen; Li, Xuefeng; Qiu, Lihong; Wang, Chengju

    2012-11-01

    The toxic effects of buprofezin on Daphnia magna after both chronic and acute exposures were evaluated according to OECD guidelines. A 48-h acute exposure of buprofezin resulted in daphnid immobility at an EC(50) of 0.44 mg/L. In a 14 days chronic exposure of buprofezin (0, 0.025, 0.05, 0.10 and 0.15 mg/L), the development and reproduction of daphnids were all significantly affected and the body length was more sensitive than other observed parameters. However, the adverse effects of buprofezin on parental daphnids can be passed on to their offspring and cannot be recovered in a short time.

  11. Evaluation of the annual killifish Nothobranchius guentheri as a tool for rapid acute toxicity screening

    SciTech Connect

    Shedd, T.R.; Widder, M.W.; Toussaint, M.W.; Sunkel, M.C.; Hull, E.

    1999-10-01

    This study evaluated the use of Nothobranchius guentheri as a novel organism for rapid acute toxicity screening. A major advantage of the species is that there is no need to maintain a continuous culture to have organisms immediately available for testing. Rather, the embryos are viable under long-term storage conditions and can be hatched within a few hours. The tests require only 24 h with standard laboratory equipment. Sensitivity levels for 11 representative toxicants were comparable to those reported for five of the standard US Environmental Protection Agency test species requiring continuous culture.

  12. Acute toxicity of PCB congeners to Daphnia magma and Pimephales promelas

    SciTech Connect

    Dillon, T.M. ); Burton, W.D.S. )

    1991-02-01

    The acute toxicity (EC50/LC50) of commercial PCB mixtures has been reported to range from 2.0 to 283 ug/L. Because PCBs are very hydrophobic most biological studies have utilized a carrier solvent to facilitate introduction of PCBs into aqueous solution. As a result, biological effects are often reported at exposure concentrations exceeding water solubility. The purpose of this work was to evaluate the comparative toxicity of selected PCB congeners without carrier solvents. These tests were conducted on early life stages of two sensitive freshwater organisms, Daphnia magna and Pimephales promelas.

  13. Evaluation of acute toxicity, cytotoxicity and genotoxicity of a nickel mining waste to Oreochromis niloticus.

    PubMed

    Oliveira-Filho, Eduardo Cyrino; Muniz, Daphne Heloisa de Freitas; Ferreira, Maria Fernanda Nince; Grisolia, Cesar Koppe

    2010-11-01

    The pyrometallurgical process of mining for obtaining ferronickel involves a stage of calcinations. At this stage a residue is generated described as a calcination dust of fine black grains. Analysis of this material revealed a significant presence of Fe, around 53,000 ppm and Ni, around 14,000, beyond of other metals as Al, Mn, and Cr. Adults and larvae of Oreochromis niloticus were used to evaluate acute toxicity, cytotoxicity and genotoxicity, and histopathological effects. The data obtained show absence of toxicity in concentrations of 5, 10 and 50% but a considerable potential for bioaccumulation in the fish's body.

  14. Acute toxicity of cypermethrin to the non target organism Hyalella curvispina.

    PubMed

    Mugni, Hernán; Paracampo, Ariel; Marrochi, Natalia; Bonetto, Carlos

    2013-01-01

    The acute toxicity of cypermethrin to the amphipod Hyalella curvispina was evaluated by means of a toxicity test under laboratory conditions. Cypermethrin is one of the most widely used insecticides in Argentina. H. curvispina is a widely distributed and commonly abundant component of the invertebrate assemblages in shallow waters of southern South America. The experiments were repeated three times. The mean 48-h LC(50) value for H. curvispina was estimated at 0.066μg/l. H. curvispina represents a good model for exotoxicological risk assessment.

  15. Toxicity of zinc oxide nanoparticles in rats treated by two different routes: single intravenous injection and single oral administration.

    PubMed

    Choi, Jonghye; Kim, Heyjin; Kim, Pilje; Jo, Eunhye; Kim, Hyun-Mi; Lee, Moo-Yeol; Jin, Seon Mi; Park, Kwangsik

    2015-01-01

    Toxicokinetics of zinc oxide nanoparticles (ZnONP) was studied in rats via a single intravenous (iv) injection and a single oral administration (3 mg/kg or 30 mg/kg), respectively. Blood concentrations of zinc (Zn) were monitored for 7 d and tissue distribution were determined in liver, kidneys, lung, spleen, thymus, brain, and testes. To ascertain the excretion of ZnONP, Zn levels in urine and feces were measured for 7 d. ZnONP were not readily absorbed from the gastrointestinal tract (GIT) after oral administration and were excreted mostly in feces. When the nanoparticles were injected iv to rats at a dose of 30 mg/kg, peak concentration appeared at 5 min but returned to normal range by d 2 (48 h after injection). ZnONP were distributed mainly to liver, kidneys, lung, and spleen, but not to thymus, brain, and testes. The distribution level was significantly decreased to normal by d 7. Feces excretion levels after iv injection supported biliary excretion of ZnONP. In rats injected iv with 30 mg/kg, mitotic figures in hepatocytes were significantly increased and multifocal acute injuries with dark brown pigment were noted in lungs, while no significant damage was observed in rats treated orally with the same dosage.

  16. Effects of Lumbriculus variegatus (Annelida, Oligochaete) bioturbation on zinc sediment chemistry and toxicity to the epi-benthic invertebrate Chironomus tepperi (Diptera: Chironomidae).

    PubMed

    Colombo, Valentina; Pettigrove, Vincent J; Hoffmann, Ary A; Golding, Lisa A

    2016-09-01

    Classical laboratory-based single-species sediment bioassays do not account for modifications to toxicity from bioturbation by benthic organisms which may impact predictions of contaminated sediment risk to biota in the field. This study aims to determine the effects of bioturbation on the toxicity of zinc measured in a standard laboratory bioassay conducted with chironomid larvae (Chironomus tepperi). The epi-benthic chironomid larvae were exposed to two different levels of sediment contamination (1600 and 1980 mg/kg of dry weight zinc) in the presence or absence of annelid worms (Lumbriculus variegatus) which are known to be tolerant to metal and to have a large impact on sediment properties through bioturbation. Chironomids had 5-6x higher survival in the presence of L. variegatus which shows that bioturbation had a beneficial effect on the chironomid larvae. Chemical analyses showed that bioturbation induced a flux of zinc from the pore water into the water column, thereby reducing the bioavailability of zinc in pore water to the chironomid larvae. This also suggested that pore water was the major exposure path for the chironomids to metals in sediment. During the study, annelid worms (Oligochaetes) produced a thin layer of faecal pellets at the sediment surface, a process known to: (i) create additional adsorption sites for zinc, thus reducing its availability, (ii) increase the microbial abundance that in turn could represent an additional food source for opportunistic C. tepperi larvae, and (iii) modify the microbial community's structure and alter the biogeochemical processes it governs thus indirectly impact zinc toxicity. This study represents a contribution in recognising bioturbating organisms as "ecological engineers" as they directly and indirectly influence metal bioavailability and impact other sediment-inhabiting species. This is significant and should be considered in risk assessment of zinc levels (and other metals) in contaminated sediment

  17. Protective effect of ginger and zinc chloride mixture on the liver and kidney alterations induced by malathion toxicity.

    PubMed

    Baiomy, Ahmed A; Attia, Hossam F; Soliman, Mohamed M; Makrum, Omar

    2015-03-01

    This study was carried out on four groups of male Wistar rats, 10 rats per group. Group I got open access to food intake and water with normal balanced diet. Group II was administered 400 mg ginger per kg body weight (BW) and zinc chloride (ZnCl2) (300 mg/L) diluted in tap water for 4 months. Group III was administered malathion at a dose of 50 mg/kg BW/day in 0.2 mL corn oil via gavages for 4 months. This dose equal to 1/50 of the LD50. Group IV was given a mixture of 400 mg ginger per kg BW and ZnCl2 (300 mg/L) diluted in tap water in addition to 100 mg malathion/kg BW for 4 months. The liver showed histopathological changes include congestion, edema, and leucocytic infiltrations which were ameliorated by the addition of ginger and ZnCl2 mixture. The kidney showed cloudy swelling and hydropic degeneration of the renal tubules. These changes were ameliorated by the addition of ginger and ZnCl2 mixture. Ki67 immunoreactivity was localized in the cytoplasm and nuclear membrane. Its expression was estimated as the percentage of cells positively stained by the antibody in the different groups. In conclusion, malathion was toxic to the liver and kidney and must be avoided and protected by the addition of ginger and zinc mixture.

  18. Zinc oxide nanoparticles (ZnONPs) alleviate heavy metal-induced toxicity in Leucaena leucocephala seedlings: A physiochemical analysis.

    PubMed

    Venkatachalam, P; Jayaraj, M; Manikandan, R; Geetha, N; Rene, Eldon R; Sharma, N C; Sahi, S V

    2017-01-01

    The present study describes the role of zinc oxide nanoparticles (ZnONPs) in reversing oxidative stress symptoms induced by heavy metal (Cd and Pb) exposure in Leucaena leucocephala (Lam.) de Wit. Seedling growth was significantly enhanced with the augmentation of ZnONPs following Cd and Pb exposure. Heavy metal accumulations were recorded as 1253.1 mg Cd per kg DW and 1026.8 mg Pb per kg DW for the respective treatments. Results demonstrated that ZnONPs augmentation caused an increase in photosynthetic pigment and total soluble protein contents while a significant decrease in malondialdehyde (MDA-lipid peroxidation) content in leaves. Antioxidative enzymes such as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX) were, in turn, elevated in heavy metal-exposed leaves amended with ZnONPs. The ameliorating effect of ZnO nanoparticles on oxidative stress induced toxicity was also confirmed by the reduced MDA content and the elevated level of antioxidative enzyme activities in leaf tissues of L. leucocephala seedlings. Further, addition of ZnONPs in combination with Cd and Pb metals induced distinct genomic alterations such as presence of new DNA bands and/or absence of normal bands in the RAPD pattern of the exposed plants. This study uniquely suggests a potential role of zinc oxide nanoparticles in the remediation of heavy metal contaminated media.

  19. Glucose deprivation stimulates Cu(2+) toxicity in cultured cerebellar granule neurons and Cu(2+)-dependent zinc release.

    PubMed

    Isaev, Nickolay K; Genrikhs, Elisaveta E; Aleksandrova, Olga P; Zelenova, Elena A; Stelmashook, Elena V

    2016-05-27

    Copper chloride (0.01mM, 2h) did not have significant influence on the survival of cerebellar granule neurons (CGNs) incubated in balanced salt solution. However, CuCl2 caused severe neuronal damage by glucose deprivation (GD). The glutamate NMDA-receptors blocker MK-801 partially and antioxidant N-acetyl-l-cysteine (NAC) or Zn(2+) chelator, N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) almost entirely protected CGNs from this toxic effect. Measurements of intracellular calcium ions using Fluo-4 AM, or zinc ions with FluoZin-3 AM demonstrated that 1 h-exposure to GD induced intensive increase of Fluo-4 but not FluoZin-3 fluorescence in neurons. The supplementation of solution with CuCl2 caused an increase of FluoZin-3, Fluo-4 and CellROX Green (reactive oxygen species probe) fluorescence by GD. The stimulation of Fluo-4 but not FluoZin-3 fluorescence by copper could be prevented partially by MK-801 and as well as CellROX Green fluorescence by NAC at GD. This data imply that during GD copper ions induce intense displacement zinc ions from intracellular stores, in addition free radical production, glutamate release and Ca(2+) overload of CGNs, that causes death of neurons as a result.

  20. Levels of cadmium and zinc in soil and plants following the toxic spill from a pyrite mine, Aznalcollar, Spain.

    PubMed

    Pain, Deborah J; Meharg, Andrew; Sinclair, Gillian; Powell, Nicola; Finnie, Jill; Williams, Robert; Hilton, Geoff

    2003-02-01

    On 25 April 1998, a breach of the tailings dam of the Los Frailes pyrite mine in southwestern Spain resulted in the release of 6 million m3 of acidic water and toxic sludge high in heavy metals. Contaminated material extended 40 km downstream, affecting agricultural land and parts of the wildlife-rich Doñana Natural and National Parks, including the Entremuros, a very important area for birds. We report on the concentrations, distributions and bioavailability of zinc and cadmium in soil and vegetation from the Entremuros in November 1998 and October 1999, following 2 'cleanup' operations. Levels of Zn and Cd in soil increased significantly over this period, although this was not reflected consistently in metal concentrations in emergent macrophytes. We recommend monitoring of further cleanup attempts in order to develop means of minimizing potential impacts to wildlife in the area.

  1. HMX: Analysis of Dosing Formulations Used in Acute, Sub-Acute and Sub-Chronic Toxicity Studies.

    DTIC Science & Technology

    1985-07-31

    14.72 - 1 50 78 1 79 1 1 I I 72 15.30 1 I 50 781 I I I 3 1 1 1 1 5 0 1 1 1 I i 15.07 -5 1 112 1 ,? 3 1 4,3 74 15.251 " 1 1 50 1 114 1 113 0 I I I 75...NUMBER 2. GOVT ACCESSION NO 3 . RECIPIENT’S CATALOG NUMBER 4. TITLE (end Subtitle) S. TYPE OF REPORT & PERIOD COVERED HMX: Analysis of dosing formulations...HMX: Analysis of Dosing Formulations Used in Acute, Sub-acute and Sub-chronic Toxicity Studies Final Report by: M.S. Henderson 3 , July,, 1985 Supported

  2. Acute oral toxicity of chemicals in terrestrial life stages of amphibians: Comparisons to birds and mammals.

    PubMed

    Crane, Mark; Finnegan, Meaghean; Weltje, Lennart; Kosmala-Grzechnik, Sylwia; Gross, Melanie; Wheeler, James R

    2016-10-01

    Amphibians are currently the most threatened and rapidly declining group of vertebrates and this has raised concerns about their potential sensitivity and exposure to plant protection products and other chemicals. Current environmental risk assessment procedures rely on surrogate species (e.g. fish and birds) to cover the risk to aquatic and terrestrial life stages of amphibians, respectively. Whilst a recent meta-analysis has shown that in most cases amphibian aquatic life stages are less sensitive to chemicals than fish, little research has been conducted on the comparative sensitivity of terrestrial amphibian life stages. Therefore, in this paper we address the questions "What is the relative sensitivity of terrestrial amphibian life stages to acute chemical oral exposure when compared with mammals and birds?" and "Are there correlations between oral toxicity data for amphibians and data for mammals or birds?" Identifying a relationship between these data may help to avoid additional vertebrate testing. Acute oral amphibian toxicity data collected from the scientific literature and ecotoxicological databases were compared with toxicity data for mammals and birds. Toxicity data for terrestrial amphibian life stages are generally sparse, as noted in previous reviews. Single-dose oral toxicity data for terrestrial amphibian life stages were available for 26 chemicals and these were positively correlated with LD50 values for mammals, while no correlation was found for birds. Further, the data suggest that oral toxicity to terrestrial amphibian life stages is similar to or lower than that for mammals and birds, with a few exceptions. Thus, mammals or birds are considered adequate toxicity surrogates for use in the assessment of the oral exposure route in amphibians. However, there is a need for further data on a wider range of chemicals to explore the wider applicability of the current analyses and recommendations.

  3. Acute sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to copper, cadmium, or zinc in water-only laboratory exposures.

    PubMed

    Calfee, Robin D; Little, Edward E; Puglis, Holly J; Scott, Erinn; Brumbaugh, William G; Mebane, Christopher A

    2014-10-01

    The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47 µg Cd/L to 2.62 µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46 µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02 µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51 µg Cu/L to 21.9 µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model-normalized EC50 of 209 µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution.

  4. Acute sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to copper, cadmium, or zinc in water-only laboratory exposures

    USGS Publications Warehouse

    Calfee, Robin D.; Little, Edward E.; Puglis, Holly J.; Scott, Erinn L.; Brumbaugh, William G.; Mebane, Christopher A.

    2014-01-01

    The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47 µg Cd/L to 2.62 µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46 µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02 µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51 µg Cu/L to 21.9 µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model–normalized EC50 of 209 µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution.

  5. Acute sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to copper, cadmium, or zinc in water-only laboratory exposures

    PubMed Central

    Calfee, Robin D; Little, Edward E; Puglis, Holly J; Scott, Erinn; Brumbaugh, William G; Mebane, Christopher A

    2014-01-01

    The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47 µg Cd/L to 2.62 µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46 µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02 µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51 µg Cu/L to 21.9 µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model–normalized EC50 of 209 µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution. Environ Toxicol Chem 2014;33:2259–2272. © 2014. The Authors. This article is a US government work and, as such, is in the public domain in the United States of America. Environmental Toxicology and Chemistry published byWiley Periodicals, Inc. on behalf of SETAC. This is an open access article

  6. Toxicological evaluation of neem (Azadirachta indica) oil: acute and subacute toxicity.

    PubMed

    Deng, Yun-xia; Cao, Mei; Shi, Dong-xia; Yin, Zhong-qiong; Jia, Ren-yong; Xu, Jiao; Wang, Chuan; Lv, Cheng; Liang, Xiao-xia; He, Chang-liang; Yang, Zhi-rong; Zhao, Jian

    2013-03-01

    Neem (Azadirachta indica), popularly known as traditional medicine is a native plant in India. Neem oil is a vegetable oil derived from seeds or fruits of the neem tree through pressing or solvent extraction, and largely used in popular medicine to have antifungal, antibacterial, antimalarial, antiparasitic, anti-inflammatory, as well as immunemodulatory properties in different animal species. In the present study, acute and 28-day subacute toxicity tests were carried out. In the acute toxicity test, the LD50 values of neem oil were found to be 31.95g/kg. The subacute treatment with neem oil failed to change body weight gain, food and water consumption. Serum biochemistry analysis showed no significant differences in any of the parameters examined under the dose of 1600mg/kg/day. Histopathological exams showed that the target organs of neem oil were testicle, liver and kidneys up to the dose of 1600mg/kg/day.

  7. The toxicity of zinc oxide nanoparticles to Lemna minor (L.) is predominantly caused by dissolved Zn.

    PubMed

    Chen, Xiaolin; O'Halloran, John; Jansen, Marcel A K

    2016-05-01

    Nano-ZnO particles have been reported to be toxic to many aquatic organisms, although it is debated whether this is caused by nanoparticles per sé, or rather dissolved Zn. This study investigated the role of dissolved Zn in nano-ZnO toxicity to Lemna minor. The technical approach was based on modulating nano-ZnO dissolution by either modifying the pH of the growth medium and/or surface coating of nano-ZnO, and measuring resulting impacts on L. minor growth and physiology. Results show rapid and total dissolution of nano-ZnO in the medium (pH 4.5). Quantitatively similar toxic effects were found when L. minor was exposed to nano-ZnO or the "dissolved Zn equivalent of dissolved nano-ZnO". The conclusion that nano-ZnO toxicity is primarily caused by dissolved Zn was further supported by the observation that phytotoxicity was absent on medium with higher pH-values (>7), where dissolution of nano-ZnO almost ceased. Similarly, the reduced toxicity of coated nano-ZnO, which displays a slower Zn dissolution, is also consistent with a major role for dissolved Zn in nano-ZnO toxicity.

  8. Acute Toxicity in High-Risk Prostate Cancer Patients Treated With Androgen Suppression and Hypofractionated Intensity-Modulated Radiotherapy

    SciTech Connect

    Pervez, Nadeem; Small, Cormac; MacKenzie, Marc; Yee, Don; Parliament, Matthew; Ghosh, Sunita; Mihai, Alina; Amanie, John; Murtha, Albert; Field, Colin; Murray, David; Fallone, Gino; Pearcey, Robert

    2010-01-15

    Purpose: To report acute toxicity resulting from radiotherapy (RT) dose escalation and hypofractionation using intensity-modulated RT (IMRT) treatment combined with androgen suppression in high-risk prostate cancer patients. Methods and Materials: Sixty patients with a histological diagnosis of high-risk prostatic adenocarcinoma (having either a clinical Stage of >=T3a or an initial prostate-specific antigen [PSA] level of >=20 ng/ml or a Gleason score of 8 to 10 or a combination of a PSA concentration of >15 ng/ml and a Gleason score of 7) were enrolled. RT prescription was 68 Gy in 25 fractions (2.72 Gy/fraction) over 5 weeks to the prostate and proximal seminal vesicles. The pelvic lymph nodes and distal seminal vesicles concurrently received 45 Gy in 25 fractions. The patients were treated with helical TomoTherapy-based IMRT and underwent daily megavoltage CT image-guided verification prior to each treatment. Acute toxicity scores were recorded weekly during RT and at 3 months post-RT, using Radiation Therapy Oncology Group acute toxicity scales. Results: All patients completed RT and follow up for 3 months. The maximum acute toxicity scores were as follows: 21 (35%) patients had Grade 2 gastrointestinal (GI) toxicity; 4 (6.67%) patients had Grade 3 genitourinary (GU) toxicity; and 30 (33.33%) patients had Grade 2 GU toxicity. These toxicity scores were reduced after RT; there were only 8 (13.6%) patients with Grade 1 GI toxicity, 11 (18.97%) with Grade 1 GU toxicity, and 5 (8.62%) with Grade 2 GU toxicity at 3 months follow up. Only the V60 to the rectum correlated with the GI toxicity. Conclusion: Dose escalation using a hypofractionated schedule to the prostate with concurrent pelvic lymph node RT and long-term androgen suppression therapy is well tolerated acutely. Longer follow up for outcome and late toxicity is required.

  9. [Acute toxicity of 10 Moroccan plants reported to be hypoglycemic agents].

    PubMed

    Jaouhari, J T; Lazrek, H B; Jana, M

    1999-01-01

    An acute toxicity study of twelve medicinal plants on Swiss albino mice has been carried out. The extracts were administered orally at a dose of 1 g/kg body weight. Animals were observed for 7 days and changes in weight and behaviour were noted. On the eighth day, the animals were sacrificed and an anatomo-histopathologic survey was undertaken. The results showed a change in behaviour and some histologic modifications following the administration of certain plant extracts.

  10. Studies on the role of iron in the reversal of zinc, cadmium, vanadium, nickel, and cobalt toxicities in boiler pullets

    SciTech Connect

    Blalock, T.L.

    1986-01-01

    Excess dietary iron reduced the toxicity of cadmium (Cd), cobalt (Co), nickel (Ni) and vanadium (V) in chicks. In order to gain further insight into this phenomenon, the toxicity of these elements was examined under conditions of dietary iron deficiency, ca. 10 ppm, and excess, ca. 1010 ppm. Graded levels of Cd, Co, Ni, V and also of zinc (Zn) were added to achieve toxicities of these heavy metals. In every case the iron-supplemented chicks were less susceptible to the every case the iron-supplemented chicks were less susceptible to the toxicities of these elements than were those chicks receiving the iron-deficient diet. The results of these studies revealed that Fe alters the metabolism of Zn, Cd, V, Ni and Co in livers and kidneys of chicks. The data further show that Zn, Cd, and Co alter Fe metabolism in chick livers and kidneys. Additionally, hemoglobin concentration was altered by Zn, Cd, and V, as well as Fe, in chicks. The locus of these interactions was more clearly defined using the radioactive tracers /sup 109/Cd, /sup 60/Co, /sup 63/Ni, /sup 48/V, and /sup 65/Zn. Iron deficiency increased absorption of Co and Ni, reduced liver retention of Cd, and Zn without affecting absorption and increased blood and liver levels of V, possibly as a result of decreased bone uptake. The alteration of liver metabolism of Cd and Zn in iron deficiency was investigated using column chromatography and atomic absorption spectrophotometry. Adequate dietary iron appears to act synergistically with Cd and Zn to induce metallothionein in the liver. Increased dietary Fe was observed to result in an increased liver influx of Zn and Cd. It is possible that iron acts in this manner to induce metallothionein synthesis.

  11. The submitochondrial particle assay as a screening test for acute aquatic toxicity of surfactant molecules

    SciTech Connect

    Bookland, E.A.; Bettermann, A.D.

    1995-12-31

    Two complementary protocols of the submitochondrial particle assay (SMP) were evaluated as screening tools for predicting the acute aquatic toxicity of various classes and chain lengths of surfactant molecules. SMP contain the functionally intact mitochondrial enzyme systems responsible for electron transport and oxidative phosphorylation. Both the Electron Transfer Assay (ETR) and the Reverse Electron Transfer Assay (RET) have been shown in prior work to generally be sensitive to agents capable of membrane and protein interactions, both suspected mechanisms of action for surfactants. The toxicity of ten compounds; four anionic surfactants, C{sub 12} alkyl sulfate (C{sub 12}AS), C{sub 12} and C{sub 15} alkyl ethoxy sulfate (C{sub 12}E{sub 4}S, C{sub 15}E{sub 4}S), linear alkyl benzene sulfonate (C{sub 12.3}LAS); one nonionic surfactant, alkyl ethoxylate (C{sub 12}E{sub 3}); three cationic surfactants, C{sub 8}, C{sub 12}, and C{sub 16} alkyl trimethyl ammonium chloride (C{sub 8}TMAC, C{sub 12}TMAC, C{sub 16}TMAC); an alcohol (C{sub 12}OH); and an amine, alkyl dimethylamine (C{sub 12}DMA); was determined. In all cases, both the ETR and the RET gave results showing equal or greater sensitivity than previously reported acute fish and invertebrate LC{sub 50}`s. In addition, increasing toxicity with increasing alkyl chain length was observed. As a rapid screening tool, the SMP bioassay avoids exposure concerns such as degradation of test material, a common concern for acute in vivo toxicity testing with rapidly degradable materials. Results indicate that the SMP bioassay can be useful as a predictive screening tool for the aquatic toxicity of surfactants.

  12. The acute whole effluent toxicity of storm water from an international airport

    SciTech Connect

    Fisher, D.J.; Turley, S.D.; Turley, B.S.; Yonkos, L.T.; Ziegler, G.P.; Knott, M.H.

    1995-06-01

    In October 1990, the US Environmental Protection Agency promulgated application requirements with deadlines for storm-water discharges associated with industrial activity and certain municipal systems. Major airports have a number of hydrocarbon-based contaminants that could appear in storm-water runoff. In addition, ethylene, diethylene, and propylene glycol deicing and anti-icing mixtures are used during freezing and near-freezing weather. The objective of this study was to characterize the potential acute impact on aquatic life from industrial storm-water discharges from an international airport. Samples from winter storm events caused acute toxicity to both the fathead minnow (Pimephales promelas) and the daphnid (Daphnia magna), with LC50 values for both species as low as 1.0 and 2.0% effluent. The toxicity of the samples was due to the various glycol-based deicer/anti-icer mixtures used during these events. High oxygen demands and elevated total nitrogen levels are other potential problems during anti-icing/deicing activities. Samples from rain events during the nonwinter months at the airport did not cause acute toxicity unless associated with fuel spills. As a result of this study, a new discharge permit has been issued for this airport, requiring the implementation of plans for the collection and recycling and/or disposal of the deicer/anti-icer mixtures.

  13. Enantioselective acute toxicity effects and bioaccumulation of furalaxyl in the earthworm (Eisenia foetida).

    PubMed

    Qin, Fang; Gao, Yongxin; Guo, Baoyuan; Xu, Peng; Li, Jianzhong; Wang, Huili

    2014-06-01

    The enantioselectivities of individual enantiomers of furalaxyl in acute toxicity and bioaccumulation in the earthworm (Eisenia foetida) were studied. The acute toxicity was tested by filter paper contact test. After 48 h of exposure, the calculated LC50 values of the R-form, rac-form, and S-form were 2.27, 2.08, and 1.22 µg cm(-2), respectively. After 72 h of exposure, the calculated LC50 values were 1.90, 1.54, and 1.00 µg cm(-2), respectively. Therefore, the acute toxicity of furalaxyl enantiomers was enantioselective. During the bioaccumulation experiment, the enantiomer fraction of furalaxyl in earthworm tissue was observed to deviate from 0.50 and maintained a range of 0.55-0.60; in other words, the bioaccumulation of furalaxyl was enantioselective in earthworm tissue with a preferential accumulation of S-furalaxyl. The uptake kinetic of furalaxyl enantiomers fitted the first-order kinetics well and the calculated kinetic parameters were consistent with the low accumulation efficiency.

  14. The potentiation of zinc toxicity by soil moisture in a boreal forest ecosystem.

    PubMed

    Owojori, Olugbenga J; Siciliano, Steven D

    2015-03-01

    Northern boreal forests often experience forest dieback as a result of metal ore mining and smelting. The common solution is to lime the soil, which increases pH, reducing metal toxicity and encouraging recovery. In certain situations, however, such as in Flin Flon, Manitoba, Canada, liming has yielded only moderate benefits, with some locations responding well to liming and other locations not at all. In an effort to increase the effectiveness of the ecorestoration strategy, the authors investigated if these differences in liming responsiveness were linked to differences in toxicity. Toxicity of metal-impacted Flin Flon soils on the oribatid mite Oppia nitens and the collembolan Folsomia candida was assessed, with a view toward identifying the metal of concern in the area. The effects of moisture content on metal sorption, uptake, and toxicity to the invertebrates were also investigated. Toxicity tests with the invertebrates were conducted using either Flin Flon soils or artificial soils with moisture content adjusted to 30%, 45%, 60%, or 75% of the maximum water-holding capacity of the soil samples. The Relative to Cd Toxicity Model identified Zn as the metal of concern in the area, and this was confirmed using validation tests with field contaminated soils. Furthermore, increasing the moisture content in soils increased the amount of mobile Zn available for uptake with the ion exchange resin. Survival and reproduction of both invertebrates were reduced under Zn exposure as moisture level increased. Thus, moisture-collecting landforms, which are often also associated with high Zn concentrations at Flin Flon, have, as a result, higher Zn toxicity to the soil ecosystem because of increases in soil moisture.

  15. The Role of Copper and Zinc Toxicity in Innate Immune Defense against Bacterial Pathogens*

    PubMed Central

    Djoko, Karrera Y.; Ong, Cheryl-lynn Y.; Walker, Mark J.; McEwan, Alastair G.

    2015-01-01

    Zinc (Zn) and copper (Cu) are essential for optimal innate immune function, and nutritional deficiency in either metal leads to increased susceptibility to bacterial infection. Recently, the decreased survival of bacterial pathogens with impaired Cu and/or Zn detoxification systems in phagocytes and animal models of infection has been reported. Consequently, a model has emerged in which the host utilizes Cu and/or Zn intoxication to reduce the intracellular survival of pathogens. This review describes and assesses the potential role for Cu and Zn intoxication in innate immune function and their direct bactericidal function. PMID:26055706

  16. The Role of Copper and Zinc Toxicity in Innate Immune Defense against Bacterial Pathogens.

    PubMed

    Djoko, Karrera Y; Ong, Cheryl-lynn Y; Walker, Mark J; McEwan, Alastair G

    2015-07-31

    Zinc (Zn) and copper (Cu) are essential for optimal innate immune function, and nutritional deficiency in either metal leads to increased susceptibility to bacterial infection. Recently, the decreased survival of bacterial pathogens with impaired Cu and/or Zn detoxification systems in phagocytes and animal models of infection has been reported. Consequently, a model has emerged in which the host utilizes Cu and/or Zn intoxication to reduce the intracellular survival of pathogens. This review describes and assesses the potential role for Cu and Zn intoxication in innate immune function and their direct bactericidal function.

  17. Acute toxicity reduction and toxicity identification in pigment-contaminated wastewater during anaerobic-anoxic-oxic (A/A/O) treatment process.

    PubMed

    Deng, Minjie; Zhang, Ying; Quan, Xie; Na, Chunhong; Chen, Shuo; Liu, Wei; Han, Shuping; Masunaga, Shigeki

    2017-02-01

    In China, a considerable part of industrial wastewater effluents are discharged into the municipal wastewater treatment plants (WWTPs) after pretreatment in their own wastewater treatment plants. Even though the industrial effluents meet the professional emission standards, many micro-pollutants still remained, and they could be resistant in the municipal WWTPs with conventional activated sludge process. Pigment wastewater was chosen in this study, and the acute toxicity reduction and identification of the pigment-contaminated wastewater treated by the conventional anaerobic-anoxic-oxic (A/A/O) process were evaluated. Results indicated that the raw pigment-contaminated wastewater was acutely toxic to Photobacterium phosphoreum (P. phosphoreum), Daphnia magna (D. magna) and Danio rerio (D. rerio). The acute toxicity was decreased in some degree after A/A/O treatment, but the final effluent still exhibited acute toxicity to D. magna and D. rerio with the toxic units (TU) of 1.1 and 2.0, respectively. Chemical analyses showed the presence of various refractory and toxic nitrogen-containing polycyclic and heterocyclic compounds in the pigment-contaminated wastewater. Toxicity identification by combining chemical analyses and correlation analysis showed that N-containing refractory organic toxicants were the main toxicity source for the pigment-contaminated wastewater, and several toxicants showed significant correlation with P. phosphoreum and D. magna. This study indicated that the A/A/O process was not efficient for pigment-contaminated wastewater treatment, and it was irradiative for technology improvement in the WWTPs receiving pretreated industrial wastewater effluents.

  18. Acute photo-induced toxicity and toxicokinetics of single compounds and mixtures of polycyclic aromatic hydrocarbons in zebrafish.

    PubMed

    Willis, Alison M; Oris, James T

    2014-09-01

    The present study examined photo-induced toxicity and toxicokinetics for acute exposure to selected polycyclic aromatic hydrocarbons (PAHs) in zebrafish. Photo-enhanced toxicity from co-exposure to ultraviolet (UV) radiation and PAHs enhanced the toxicity and exhibited toxic effects at PAH concentrations orders of magnitude below effects observed in the absence of UV. Because environmental exposure to PAHs is usually in the form of complex mixtures, the present study examined the photo-induced toxicity of both single compounds and mixtures of PAHs. In a sensitive larval life stage of zebrafish, acute photo-induced median lethal concentrations (LC50s) were derived for 4 PAHs (anthracene, pyrene, carbazole, and phenanthrene) to examine the hypothesis that phototoxic (anthracene and pyrene) and nonphototoxic (carbazole and phenanthrene) pathways of mixtures could be predicted from single exposures. Anthracene and pyrene were phototoxic as predicted; however, carbazole exhibited moderate photo-induced toxicity and phenanthrene exhibited weak photo-induced toxicity. The toxicity of each chemical alone was used to compare the toxicity of mixtures in binary, tertiary, and quaternary combinations of these PAHs, and a predictive model for environmental mixtures was generated. The results indicated that the acute toxicity of PAH mixtures was additive in phototoxic scenarios, regardless of the magnitude of photo-enhancement. Based on PAH concentrations found in water and circumstances of high UV dose to aquatic systems, there exists potential risk of photo-induced toxicity to aquatic organisms.

  19. Artemia salina as test organism for assessment of acute toxicity of leachate water from landfills.

    PubMed

    Svensson, B M; Mathiasson, L; Mårtensson, L; Bergström, S

    2005-03-01

    Artemia salina has, for the first time, been used as test organism for acute toxicity of leachate water from three landfills (the municipal landfills at Kristianstad, Sweden and Siauliai, Lithuania, and an industrial landfill at Stena fragmenting AB, Halmstad, as well as for leachate from Kristianstad treated in different ways in a pilot plan). Artemia can tolerate the high concentrations of chloride ions found in such waters. Large differences in toxicities were found, the leachate from Siauliai being the most toxic one. To increase the selectivity in the measurements, a fractionation was done by using ion exchange to separate ammonium/ammonia and metal ions from the leachate, and activated carbon adsorbents for organic pollutants. The influence of some metals and phenol compounds on the toxicity was investigated separately. It was found that most of the toxicity emanated from the ammonium/ammonia components in the leachate. However, there was also a significant contribution n from organic pollutants, other than phenol compounds, since separate experiments had in this latter case indicated negligible impact. The concentrations of metals were at a level, shown by separate experiments, where only small contribution to the toxicity could be expected.

  20. Acute and Subchronic Toxicity Study of Euphorbia hirta L. Methanol Extract in Rats

    PubMed Central

    Yuet Ping, Kwan; Darah, Ibrahim; Chen, Yeng; Sreeramanan, Subramaniam

    2013-01-01

    Despite Euphorbia hirta L. ethnomedicinal benefits, very few studies have described the potential toxicity. The aim of the present study was to evaluate the in vivo toxicity of methanolic extracts of E. hirta. The acute and subchronic oral toxicity of E. hirta was evaluated in Sprague Dawley rats. The extract at a single dose of 5000 mg/kg did not produce treatment related signs of toxicity or mortality in any of the animals tested during the 14-day observation period. Therefore, the LD 50 of this plant was estimated to be more than 5000 mg/kg. In the repeated dose 90-day oral toxicity study, the administration of 50 mg/kg, 250 mg/kg, and 1000 mg/kg/day of E. hirta extract per body weight revealed no significant difference (P > 0.05) in food and water consumptions, body weight change, haematological and biochemical parameters, relative organ weights, and gross findings compared to the control group. Macropathology and histopathology examinations of all organs including the liver did not reveal morphological alteration. Analyses of these results with the information of signs, behaviour, and health monitoring could lead to the conclusion that the long-term oral administration of E. hirta extract for 90 days does not cause sub-chronic toxicity. PMID:24386634

  1. Safety Evaluation of Zingiber cassumunar Roxb. Rhizome Extract: Acute and Chronic Toxicity Studies in Rats

    PubMed Central

    Koontongkaew, Sittichai; Poachanukoon, Orapan; Sireeratawong, Seewaboon; Dechatiwongse Na Ayudhya, Thaweephol; Khonsung, Parirat; Jaijoy, Kanjana; Soawakontha, Ruedee; Chanchai, Monraudee

    2014-01-01

    Zingiber cassumunar Roxb. has been used for traditional medicine, but few studies have described its potential toxicity. In this study, the acute and chronic oral toxicity of Z. cassumunar extract granules were evaluated in Sprague-Dawley rats. The extract at a single dose of 5000 mg/kg body weight did not produce treatment related signs of toxicity or mortality in any of the animals tested during the 14-day observation period. However, a decrease in body weights was observed in treated males (P < 0.05). The weights of lung and kidney of treated females were increased (P < 0.05). Treated males were increased in spleen and epididymis weights (P < 0.05). In repeated dose 270-day oral toxicity study, the administration of the extracts at concentrations of 0.3, 3, 30, 11.25, 112.5, and 1,125 mg/kg body weight/day revealed no-treatment toxicity. Although certain endpoints among those monitored (i.e., organ weight, hematological parameters, and clinical chemistry) exhibited statistically significant effects, none was adverse. Gross and histological observations revealed no toxicity. Our findings suggest that the Z. cassumunar extract granules are well tolerated for both single and chronic administration. The oral no-observed-adverse-effect level (NOAEL) for the extract was 1,125 mg/kg body weight/day for males and females. PMID:27379341

  2. Safety Evaluation of Zingiber cassumunar Roxb. Rhizome Extract: Acute and Chronic Toxicity Studies in Rats.

    PubMed

    Koontongkaew, Sittichai; Poachanukoon, Orapan; Sireeratawong, Seewaboon; Dechatiwongse Na Ayudhya, Thaweephol; Khonsung, Parirat; Jaijoy, Kanjana; Soawakontha, Ruedee; Chanchai, Monraudee

    2014-01-01

    Zingiber cassumunar Roxb. has been used for traditional medicine, but few studies have described its potential toxicity. In this study, the acute and chronic oral toxicity of Z. cassumunar extract granules were evaluated in Sprague-Dawley rats. The extract at a single dose of 5000 mg/kg body weight did not produce treatment related signs of toxicity or mortality in any of the animals tested during the 14-day observation period. However, a decrease in body weights was observed in treated males (P < 0.05). The weights of lung and kidney of treated females were increased (P < 0.05). Treated males were increased in spleen and epididymis weights (P < 0.05). In repeated dose 270-day oral toxicity study, the administration of the extracts at concentrations of 0.3, 3, 30, 11.25, 112.5, and 1,125 mg/kg body weight/day revealed no-treatment toxicity. Although certain endpoints among those monitored (i.e., organ weight, hematological parameters, and clinical chemistry) exhibited statistically significant effects, none was adverse. Gross and histological observations revealed no toxicity. Our findings suggest that the Z. cassumunar extract granules are well tolerated for both single and chronic administration. The oral no-observed-adverse-effect level (NOAEL) for the extract was 1,125 mg/kg body weight/day for males and females.

  3. Acute toxicity tests and meta-analysis identify gaps in tropical ecotoxicology for amphibians.

    PubMed

    Ghose, Sonia L; Donnelly, Maureen A; Kerby, Jacob; Whitfield, Steven M

    2014-09-01

    Amphibian populations are declining worldwide, particularly in tropical regions where amphibian diversity is highest. Pollutants, including agricultural pesticides, have been identified as a potential contributor to decline, yet toxicological studies of tropical amphibians are very rare. The present study assesses toxic effects on amphibians of 10 commonly used commercial pesticides in tropical agriculture using 2 approaches. First, the authors conducted 8-d toxicity assays with formulations of each pesticide using individually reared red-eyed tree frog (Agalychnis callidryas) tadpoles. Second, they conducted a review of available data for the lethal concentration to kill 50% of test animals from the US Environmental Protection Agency's ECOTOX database to allow comparison with their findings. Lethal concentration estimates from the assays ranged over several orders of magnitude. The nematicides terbufos and ethoprophos and the fungicide chlorothalonil were very highly toxic, with evident effects within an order of magnitude of environmental concentrations. Acute toxicity assays and meta-analysis show that nematicides and fungicides are generally more toxic than herbicides yet receive far less research attention than less toxic herbicides. Given that the tropics have a high diversity of amphibians, the findings emphasize the need for research into the effects of commonly used pesticides in tropical countries and should help guide future ecotoxicological research in tropical regions.

  4. Acute toxicity of fire-retardant and foam-suppressant chemicals to yalella azteca (Saussure)

    USGS Publications Warehouse

    McDonald, Susan F.; Hamilton, Steven J.; Buhl, Kevin J.; Heisinger, James F.

    1997-01-01

    Acute toxicity tests were conducted with Hyalella azteca Saussure (an amphipod) exposed in soft and hard waters to three fire retardants (Fire-Trol GTS-R, Fire-Trol LCG-R, and Phos-Chek D75-F) and two foam suppressants (Phos-Chek WD-881 and Silv-Ex). The chemicals were slightly to moderately toxic to amphipods. The most toxic chemical to amphipods in soft and hard water was Phos-Chek WD-881 (96-h mean lethal concentration [LC50] equal to 10 mg/L and 22 mg/L, respectively), and the least toxic chemical to amphipods in soft water was Fire-Trol GTS-R (96-h LC50 equal to 127 mg/L) and in hard water was Fire-Trol LCG-R (96-h LC50 equal to 535 mg/L). Concentrations of ammonia in tests with the three fire retardants and both water types were greater than reported LC50 values and probably were the major toxic component. Estimated un-ionized ammonia concentrations near the LC50 were frequently less than the reported LC50 ammonia concentrations for amphipods. The three fire retardants were more toxic in soft water than in hard water even though ammonia and un-ionized ammonia concentrations were higher in hard water tests than in soft water tests. The accidental entry of fire-fighting chemicals into aquatic environments could adversely affect aquatic invertebrates, thereby disrupting ecosystem function.

  5. Acute toxicity testing with the tropical marine copepod Acartia sinjiensis: optimisation and application.

    PubMed

    Gissi, F; Binet, M T; Adams, M S

    2013-11-01

    Globally there is limited toxicity data for tropical marine species, and there has been a call for further research and development in the area of tropical marine ecotoxicology. An increase in developmental pressures in northern tropical Australia is causing a higher demand for toxicity test protocols with ecologically relevant species. Copepods are a diverse group of zooplankton that are major components of marine food webs. The calanoid copepod Acartia sinjiensis is widely distributed across tropical and sub-tropical brackish to marine waters of Australia and was identified in a recent comprehensive review of marine tropical toxicity testing in Australia as a suitable test organism. Through a number of optimisation steps including feeding trials, changes to culture and test conditions; a 48-h acute toxicity test with A. sinjiensis was modified to become a highly reliable and reproducible standard test protocol. Control mobility was improved significantly, and the sensitivity of A. sinjiensis to copper (EC50 of 33µg/L), ammonia (EC50 of 10mg/L) and phenol (EC50 of 13mg/L) fell within the ranges of those reported previously, indicating that the modifications did not alter its sensitivity. In a comprehensive literature search we found that this species was the most sensitive to copper out of a range of marine copepods. The test was also successfully applied in toxicity assessments of four environmental samples: two produced formations waters (PFWs) and two mine tailing liquors (MTLs). The toxicity assessments utilised toxicity data from a suite of marine organisms (bacteria, microalgae, copepods, sea urchins, oysters, prawns, and fish). For the PFWs, which were predominantly contaminated with organic chemicals, A. sinjiensis was the most sensitive species (EC50 value 2-17 times lower than for any other test species). For the predominantly metal-contaminated mine tailing liquors, its sensitivity was similar to that of other test species used. The modified 48-h acute

  6. Acute toxicity assessment of Osthol content in bio-pesticides using two aquatic organisms

    PubMed Central

    Yim, Eun-Chae; Kim, Hyeon Joe; Kim, Seong-Jun

    2014-01-01

    Objectives This study focused on the assessment of acute toxicity caused by Osthol, a major component of environment-friendly biological pesticides, by using two aquatic organisms. Methods The assessment of acute toxicity caused by Osthol was conducted in Daphnia magna and by examining the morphological abnormalities in Danio rerio embryos. Results The median effective concentration value of Osthol in D. magna 48 hours after inoculation was 19.3 μM. The median lethal concentration of D. rerio embryo at 96 hours was 30.6 μM. No observed effect concentration and predicted no effect concentration values of Osthol in D. magna and D. rerio were calculated as 5.4 and 0.19 μM, respectively. There was an increase in the morphological abnormalities in D. rerio embryo due to Osthol over time. Coagulation, delayed hatching, yolk sac edema, pericardial edema, and pigmentation were observed in embryos at 24–48 hours. Symptoms of scoliosis and head edema occurred after 72 hours. In addition, bent tails, ocular defects, and symptoms of collapse were observed in fertilized embryo tissue within 96 hours. Ocular defects and pigmentation were the additional symptoms observed in this study. Conclusions Because Osthol showed considerable toxicity levels continuous toxicity evaluation in agro-ecosystems is necessary when bio-pesticides containing Osthol are used. PMID:25518842

  7. The Acute Inhalation Toxicity in Rats from the Pyrolysis Products of Four Fluoropolymers

    NASA Technical Reports Server (NTRS)

    Carter, V. L., Jr.; Bafus, D. A.; Warrington, H. P.; Harris, E. S.

    1974-01-01

    Male Sprague-Dawley rats (225?250 g) were exposed to the thermal degradation products from four fluoropolymers. The three polymers containing vinylidene fluoride and hexafluoropropene (VF2/HFP) were pyrolyzed at 550? and 800?C, whereas polytetrafluoroethylene (PTFE) was pyrolyzed at 625 and 800?C. At the lower temperatures, the pyrolysate from the copolymer of vinylidene fluoride and hexafluoropropene (VF2/HFP) was less toxic than the pyrolysates from either the terpolymer of vinyidene fluoride, hexafluoropropene, and tetrafluoroethylene (VF2/HFP/TFE) or the copolymer of vinylidene fluoride and hexafluoropropene with ?additives? (VF2/HFP-A). However, the pyrolysates from the VF2/HFP-containing materials produced less toxic products than the pyrolysate from PTFE at 625?C. When the pyrolysis temperature was increased to 800?C, very little difference was noted between the pyrolysis toxicity for any of the VF2/HFP-containing polymers with the most toxic pyrolysate again produced by PTFE. Carbon monoxide levels were all sublethal. No correlation could be established between hydrolyzable fluoride levels and the lethality of the pyrolysates. Death following exposure occurred within 48 hr due to acute pulmonary edema and hemorrhage. Survival of this acute phase was followed by alveolar lymphocytic infiltration and peribronchial tissue proliferation.

  8. Acute and repeated dose toxicity studies of different β-cyclodextrin-based nanosponge formulations.

    PubMed

    Shende, Pravin; Kulkarni, Yogesh A; Gaud, R S; Deshmukh, Kiran; Cavalli, Roberta; Trotta, Francesco; Caldera, Fabrizio

    2015-05-01

    Nanosponges (NS) show promising results in different fields such as medicine, agriculture, water purification, fire engineering and so on. The present study was designed to evaluate toxicity of different NS formulations (namely, S1-S6) synthesized with different cross-linking agents such as carbonyl diimidazole, pyromellitic dianhydride and hexamethylene diisocynate; and preparation methods in experimental animals. Acute and repeated dose toxicity studies of formulations were carried out as per OECD guidelines 423 and 407, respectively. For acute toxicity study, formulations were administered to female rats at doses of 300 and 2000 mg/kg orally. The general behaviour of the rats was continuously monitored for 1 h after dosing, periodically during the first 24 h and daily thereafter for a total of 14 days. On day 14, animals were fasted overnight, weighed, and sacrificed. After sacrification, animals were subjected to necropsy. For repeated dose toxicity study, rats of either sex were orally administered with formulations at the dose of 300 mg/kg per day for a period of 28 days. The maximally tolerated dose of all formulations was found to be 2000 mg/kg. Repeated administration of formulations for 28 days did not show any significant changes in haematological and biochemical parameters in experimental animals. These results indicate that the formulations are safe, when tested in experimental animals.

  9. Acute toxicity assessment of explosive-contaminated soil extracting solution by luminescent bacteria assays.

    PubMed

    Xu, Wenjie; Jiang, Zhenming; Zhao, Quanlin; Zhang, Zhenzhong; Su, Hongping; Gao, Xuewen; Ye, Zhengfang

    2016-11-01

    Explosive-contaminated soil is harmful to people's health and the local ecosystem. The acute toxicity of its extracting solution was tested by bacterial luminescence assay using three kinds of luminescent bacteria to characterize the toxicity of the soil. An orthogonal test L 16 (4(5)) was designed to optimize the soil extracting conditions. The optimum extracting conditions were obtained when the ultrasonic extraction time, ultrasonic extraction temperature, and the extraction repeat times were 6 h, 40 °C, and three, respectively. Fourier transform infrared spectroscopy (FTIR) results showed that the main components of the contaminated soil's extracting solution were 2,4-dinitrotoluene-3-sulfonate (2,4-DNT-3-SO3(-)); 2,4-dinitrotoluene-5-sulfonate (2,4-DNT-5-SO3(-)); and 2,6-dinitrotoluene (2,6-DNT). Compared with Photobacterium phosphoreum and Vibrio fischeri, Vibrio qinghaiensis sp. Nov. is more suitable for assessing the soil extracting solution's acute toxicity. Soil washing can remove most of the contaminants toxic to luminescent bacterium Vibrio qinghaiensis sp. Nov., suggesting that it may be a potential effective remediation method for explosive-contaminated soil.

  10. CerioFAST{trademark}: An acute toxicity test based on Ceriodaphnia dubia feeding behavior

    SciTech Connect

    Bitton, G.; Rhodes, K.; Koopman, B.

    1996-02-01

    The authors have developed a rapid acute toxicity test (CerioFAST{trademark}) based on suppression of feeding activity of Ceriodaphnia dubia in the presence of toxicants. The bioassay consists of a 1-h exposure period to a given toxicant. Yeast cells, stained with a fluorescent dye, are added 20 min before the end of the exposure period. Response to a toxic sample is indicated by the absence of fluorescence in the gut of the daphnids. CerioFAST was compared to the standard 48-h C. dubia acute bioassay, using heavy metals and organic compounds.CerioFAST EC50s of Cd, Cu, Pb, Ag, Zn, and carbofuran were in the 0.01--0.1-mg/L range, whereas EC50s of hexachloroethane, pentachlorophenol, trichlorophenol, and lindane were in the 1--10-mg/L range. CerioFAST EC50s of the heavy metals and organics were well correlated with Ec50s obtained with the 48-h C. dubia bioassay.

  11. Acute toxicity and toxicokinetics of dipfluzine hydrochloride, a novel calcium channel blocker.

    PubMed

    Hu, Huiqing; Wang, Yongli; Pei, Tingmei; Dong, Lei; Xu, Yanfang

    2009-06-01

    Dipfluzine hydrochloride, diphenylpiperazine calcium channel blocker, is a promising candidate to treat ischemic stroke. The purpose of the study is to evaluate the acute toxicity and toxicokinetics of dipfluzine hydrochloride after single intravenous doses in rats. Acute toxicity study was performed in rats at doses of 5, 6, 10, 15, 25, 30, 35, and 40mg/kg. Concentrations of dipfluzine in plasma and tissues were determined with a reverse-phase HPLC method after single doses of 5, 15 and 30mg/kg. The results demonstrated that no-observed-adverse-effect level (NOAEL), lowest-observed-adverse-effect level (LOAEL), maximal tolerance dose (MTD), and minimal lethal dose (MLD) were respectively 5, 6, 30, 35mg/kg for i.v. administration of dipfluzine hydrochloride. The toxicokinetic study revealed that the severity of toxicity was linear with the level of systemic exposure. The highest tissue exposure was detected in lung tissue and it may primarily contribute to the pulmonary congestion in dead rats. Longer elimination half-lives of dipfluzine in kidney, brain, liver, and pancreas imply a possible accumulation of dipfluzine in these tissues for long-term exposure. In addition, a temporary impairment in liver and heart was observed for clinical chemistry in 30mg/kg dose group. The findings will help to design further studies to characterize the repeat-dose toxicity of dipfluzine hydrochloride.

  12. Acute toxicity of some hydrazine compounds to salamander larvae, Ambystoma spp

    SciTech Connect

    Slonim, A.R.

    1986-11-01

    Although hydrazine compounds have been used extensively by industry for a very long time, they have become important in recent years as propellants for aerospace operations. The study of hydrazine compounds in this laboratory began about two decades ago and developed into a large pharmacological and toxicological research program that included also environmental considerations. Subsequently, acute toxicity studies were conducted on the common guppy (Lebistes reticulatus Peters) using four hydrazine compounds of interest. The toxicity of these propellants were evaluated next on other species of aquatic organisms such as mosquito fish (Gambusia affinis) and amphibians. Two different studies were conducted on amphibians: One utilized amphibian eggs and the other amphibian larvae. The larvae of spotted and marbled salamanders (Ambystoma maculatum and A. opacum, respectively) were used primarily in numerous static bioassays to determine the acute toxicity of hydrazine, UDMH and Aerozine-50 on these organisms. The remaining larvae were used in other tests mainly to corroborate previous experimental results (e.g., to see whether toxicity is affected by organism size, aeration of test solutions, and water hardness). The results on the larvae are presented in this paper.

  13. Effect of copper status on acute toxicity of cocaine in rats

    SciTech Connect

    Smith, J.C.; Reddy, P.P.; Seung, S.K.; Combs, G.F.; Dulin, A.M.; Danford, D.E. )

    1989-02-09

    Both copper (Cu) nutriture and cocaine (Coc) ingestion have been shown to affect cardiovascular integrity. Therefore, the purpose of these studies was to determine if Cu status affects the acute toxicity of Coc. 20 weanling male rats (45 {plus minus} 5 g) were randomly assigned to 2 groups, 1 fed a copper deficient (CuD) (<1ppmCu) and the other a copper supplemented (CuS) diet (ca.6ppm, Cu). After 7 wks, the rats, paired for Cu status, were injected (ip) with Coc-HCl at reported LD{sub 50} doses ranging from 80-90 mg/kg bw. The CuD was established by cardiac hypertrophy, depressed hematocrit, lowered serum, liver and heart Cu compared to the CuS controls. The acute toxicity resulted in tachycardia and hyperactivity followed by ataxia with isolated muscle twitchings and violent grand-mal type seizures. For those animals that died, death was apparently due to respiratory arrest followed by ventricular fibrillation; animals that survived were killed by exsanguination. The severity of toxicity was greater for the CuD rats as evidenced by 100% exhibiting seizures compared to 80% for the CuS group. In addition, the incidence of death was 60% for the CuD group compared to 20% for the CuS rats. Although these results suggest that CuD exacerbates the toxic effects of Coc, it is not established that the effects are specific for this essential nutrient.

  14. Acute and sub-chronic toxicity of aqueous extracts of Chenopodium ambrosioides leaves in rats.

    PubMed

    da Silva, Marcel Gianni C; Amorim, Raimundo Neilson L; Câmara, Carlos C; Fontenele Neto, José Domingues; Soto-Blanco, Benito

    2014-09-01

    The present study aimed to evaluate the toxicity of aqueous extract of Chenopodium ambrosioides leaves. To measure acute toxicity, rats were administered 0, 0.3, 1.0, or 3.0 g/kg of aqueous extract from C. ambrosioides leaves by gavage. To analyze sub-chronic toxicity, rats were treated by oral gavage for 15 consecutive days with 0, 0.3, or 1.0 g/kg of extract of C. ambrosioides leaves. No animals from either trial exhibited any signs of toxicity. In the acute study, the highest dose of the extract led to an increase in the serum activities of alanine transaminase (ALT) and aspartate transaminase (AST) and a decrease in the serum levels of urea. In the sub-chronic test, rats treated with 1.0 g/kg for 15 days exhibited increased serum ALT activity and creatinine levels and mild cytoplasmic vacuolation of hepatocytes. The results indicate that aqueous extract from C. ambrosioides leaves produce slight hepatotoxic lesions in rats.

  15. Safety assessment of vitacoxib: Acute and 90-day sub-chronic oral toxicity studies.

    PubMed

    Wang, Jianzhong; Sun, Feifei; Tang, Shusheng; Zhang, Suxia; Lv, Pengyue; Li, Jing; Cao, Xingyuan

    2017-02-24

    Vitacoxib, is a newly developed coxibs NSAID (selective inhibitors of cyclooxygenase-2). To date, no experimental data have been published concerning its safety for use as an additive in the human diet. In the present study, we assessed the acute and sub-chronic toxicity of vitacoxib administered by gavage. The acute toxicity tests in Sprague Dawley (SD) rats and ICR mice demonstrated that vitacoxib at a dose of 5000 mg/kg BW failed to alter any of the parameters studied. In the 90-day sub-chronic toxicity test, vitacoxib was administered to SD rats at the doses of 0 (control), 5, 10, 20, 30, and 60 mg/kg BW. The results demonstrated that there were no significant differences for most indexes of sub-chronic toxicity throughout the experiment at the dose of 5-20 mg/kg BW, indicating no apparent dose-dependent. However, there were significant histopathology changes in the liver and kidney, and alterations in some biochemical parameters in the 60 mg/kg BW group. Based on these findings, the gavage LD50 was determined to be > 5000 mg/kg in SD rats and ICR mice, and the 90-day gavage no-observed-adverse-effect level (NOAEL) of vitacoxib was considered to be 20 mg/kg BW under the present study conditions.

  16. Comparative analysis of acute toxic poisoning in 2003 and 2011: analysis of 3 academic hospitals.

    PubMed

    Jang, Hak-Soo; Kim, Jung-Youn; Choi, Sung-Hyuk; Yoon, Young-Hoon; Moon, Sung-Woo; Hong, Yun-Sik; Lee, Sung-Woo

    2013-10-01

    Social factors may affect the available sources of toxic substances and causes of poisoning; and these factors may change over time. Additionally, understanding the characteristics of patients with acute toxic poisoning is important for treating such patients. Therefore, this study investigated the characteristics of patients with toxic poisoning. Patients visiting one of 3 hospitals in 2003 and 2011 were included in this study. Data on all patients who were admitted to the emergency departments with acute toxic poisoning were retrospectively obtained from medical records. Total 939 patients were analyzed. The average age of patients was 40.0 ± 20 yr, and 335 (36.9%) patients were men. Among the elements that did not change over time were the facts that suicide was the most common cause, that alcohol consumption was involved in roughly 1 of 4 cases, and that there were more women than men. Furthermore, acetaminophen and doxylamine remained the most common poisoning agents. In conclusion, the average patient age and psychotic drug poisoning has increased over time, and the use of lavage treatment has decreased.

  17. Mycophenolate mofetil toxicity mimicking acute cellular rejection in a small intestinal transplant

    PubMed Central

    Apostolov, Ross; Asadi, Khashayar; Lokan, Julie; Kam, Ning; Testro, Adam

    2017-01-01

    Mycophenolate mofetil (MMF) is an important medication used for maintenance immunosuppression in solid organ transplants. A common gastrointestinal (GI) side effect of MMF is enterocolitis, which has been associated with multiple histological features. There is little data in the literature describing the histological effects of MMF in small intestinal transplant (SIT) recipients. We present a case of MMF toxicity in a SIT recipient, with histological changes in the donor ileum mimicking persistent acute cellular rejection (ACR). Concurrent biopsies of the patient’s native colon showed similar changes to those from the donor small bowel, suggesting a non-graft specific process, raising suspicion for MMF toxicity. The MMF was discontinued and complete resolution of these changes occurred over three weeks. MMF toxicity should therefore be considered as a differential diagnosis for ACR and graft-versus-host disease in SITs. PMID:28280702

  18. Determination of zinc oxide nanoparticles toxicity in root growth in wheat (Triticum aestivum L.) seedlings.

    PubMed

    Prakash, Meppaloor G; Chung, Ill Min

    2016-09-01

    The effect of zinc oxide nanoparticles (ZnONPs) was studied in wheat (Triticum aestivum L.) seedlings under in vitro exposure conditions. To avoid precipitation of nanoparticles, the seedlings were grown in half strength semisolid Murashige and Skoog medium containing 0, 50, 100, 200, 400 and 500 mg L(-1) of ZnONPs. Analysis of zinc (Zn) content showed significant increase in roots. In vivo detection using fluorescent probe Zynpyr-1 indicated accumulation of Zn in primary and lateral root tips. All concentrations of ZnONPs significantly reduced root growth. However, significant decrease in shoot growth was observed only after exposure to 400 and 500 mg L(-1) of ZnONPs. The reactive oxygen species and lipid peroxidation levels significantly increased in roots. Significant increase in cell-wall bound peroxidase activity was observed after exposure to 500 mg L(-1) of ZnONPs. Histochemical staining with phloroglucinol-HCl showed lignification of root cells upon exposure to 500 mg L(-1) of ZnONPs. Treatment with propidium iodide indicated loss of cell viability in root tips of wheat seedlings. These results suggest that redox imbalances, lignification and cell death has resulted in reduction of root growth in wheat seedlings exposed to ZnONPs nanoparticles.

  19. Influence of water hardness and sulfate on the acute toxicity of chloride to sensitive freshwater invertebrates.

    PubMed

    Soucek, David J; Linton, Tyler K; Tarr, Christopher D; Dickinson, Amy; Wickramanayake, Nilesh; Delos, Charles G; Cruz, Luis A

    2011-04-01

    Total dissolved solids (TDS) represent the sum of all common ions (e.g., Na, K, Ca, Mg, chloride, sulfate, and bicarbonate) in freshwater. Currently, no federal water quality criteria exist for the protection of aquatic life for TDS, but because the constituents that constitute TDS are variable, the development of aquatic life criteria for specific ions is more practical than development of aquatic life criteria for TDS. Chloride is one such ion for which aquatic life criteria exist; however, the current aquatic life criteria dataset for chloride is more than 20 years old. Therefore, additional toxicity tests were conducted in the current study to confirm the acute toxicity of chloride to several potentially sensitive invertebrates: water flea (Ceriodaphnia dubia), fingernail clams (Sphaerium simile and Musculium transversum), snail (Gyraulus parvus), and worm (Tubifex tubifex), and determine the extent to which hardness and sulfate modify chloride toxicity. The results indicated a significant ameliorating effect of water hardness (calcium and magnesium) on chloride toxicity for all species tested except the snail; for example, the 48-h chloride median lethal concentration (LC50) for C. dubia at 50 mg/L hardness (977 mg Cl(-) /L) was half that at 800 mg/L hardness (1,836 mg Cl(-) /L). Conversely, sulfate over the range of 25 to 600 mg/L exerted a negligible effect on chloride toxicity to C. dubia. Rank order of LC50 values for chloride at a given water hardness was in the order (lowest to highest): S. simile < C. dubia < M. transversum < G. parvus < T. tubifex. Results of the current study support the contention that the specific conductivity or TDS concentration of a water body alone is not a sufficient predictor of acute toxicity and that knowledge of the specific ion composition is critical.

  20. Release behavior and toxicity profiles towards A549 cell lines of ciprofloxacin from its layered zinc hydroxide intercalation compound

    PubMed Central

    2013-01-01

    Background Layered hydroxides salts (LHS), a layered inorganic compound is gaining attention in a wide range of applications, particularly due to its unique anion exchange properties. In this work, layered zinc hydroxide nitrate (LZH), a family member of LHS was intercalated with anionic ciprofloxacin (CFX), a broad spectrum antibiotic via ion exchange in a mixture solution of water:ethanol. Results Powder x-ray diffraction (XRD), Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA) confirmed the drug anions were successfully intercalated in the interlayer space of LZH. Specific surface area of the obtained compound was increased compared to that of the host due to the different pore textures between the two materials. CFX anions were slowly released over 80 hours in phosphate-buffered saline (PBS) solution due to strong interactions that occurred between the intercalated anions and the host lattices. The intercalation compound demonstrated enhanced antiproliferative effects towards A549 cancer cells compared to the toxicity of CFX alone. Conclusions Strong host-guest interactions between the LZH lattice and the CFX anion give rise to a new intercalation compound that demonstrates sustained release mode and enhanced toxicity effects towards A549 cell lines. These findings should serve as foundations towards further developments of the brucite-like host material in drug delivery systems. PMID:23849189

  1. 28-day repeated dose oral toxicity of human copper-zinc superoxide dismutase from recombinant Pichia pastori in rats.

    PubMed

    Zhu, Liang; Tian, Ying-Juan; Zhu, Si-Ming

    2012-04-01

    Human copper/zinc superoxide dismutase from recombinant Pichia pastori (RH-Cu/Zn-SOD) was orally administered, via gavage, to Sprague-Dawley rats at 500, 1,000, and 2,000 mg/kg body weight/day for 28 days. During the 28-day period, animals were examined for evidence of toxicity; there were no deaths, and in-life physical signs were normal. On day 29, the animals were exsanguinated, examined for gross pathology, and tissues were preserved for histopathology. Although statistical differences were noted in some hematology and clinical chemistry, they were of questionable biological significance. The results of the 28-day oral administration demonstrated a lack of toxicity of RH-Cu/Zn-SOD in rats. There were no treatment-related, toxicologically relevant changes in clinical signs, growth, food consumption, hematology, clinical chemistry, organ weights, or pathology. The no observed adverse effect level was greater than 2,000 mg/kg/day for RH-Cu/Zn-SOD in rats.

  2. Acute toxicity of binary and ternary mixtures of Cd, Cu, and Zn to Daphnia magna.

    PubMed

    Meyer, Joseph S; Ranville, James F; Pontasch, Mandee; Gorsuch, Joseph W; Adams, William J

    2015-04-01

    Standard static-exposure acute lethality tests were conducted with Daphnia magna neonates exposed to binary or ternary mixtures of Cd, Cu, and Zn in moderately hard reconstituted water that contained 3 mg dissolved organic carbon/L added as Suwannee River fulvic acid. These experiments were conducted to test for additive toxicity (i.e., the response to the mixture can be predicted by combining the responses obtained in single-metal toxicity tests) or nonadditive toxicity (i.e., the response is less than or greater than additive). Based on total metal concentrations (>90% dissolved) the toxicity of the tested metal mixtures could be categorized into all 3 possible additivity categories: less-than-additive toxicity (e.g., Cd-Zn and Cd-Cu-Zn mixtures and Cd-Cu mixtures when Cu was titrated into Cd-containing waters), additive toxicity (e.g., some Cu-Zn mixtures), or more-than-additive toxicity (some Cu-Zn mixtures and Cd-Cu mixtures when Cd was titrated into Cu-containing waters). Exposing the organisms to a range of sublethal to supralethal concentrations of the titrated metal was especially helpful in identifying nonadditive interactions. Geochemical processes (e.g., metal-metal competition for binding to dissolved organic matter and/or the biotic ligand, and possibly supersaturation of exposure waters with the metals in some high-concentration exposures) can explain much of the observed metal-metal interactions. Therefore, bioavailability models that incorporate those geochemical (and possibly some physiological) processes might be able to predict metal mixture toxicity accurately.

  3. An Evaluation of Select Test Variables Potentially Affecting Acute Oil Toxicity.

    PubMed

    Echols, Brandi S; Smith, A; Gardinali, P; Rand, G

    2016-02-01

    In the wake of the Deepwater Horizon incident (2010) in the Gulf of Mexico, an abundance of research studies have been performed, but the methodologies used have varied making comparisons and replication difficult. In this study, acute toxicity tests with mysids and inland silversides were performed to examine the effect of different variables on test results. The toxicity test variables evaluated in this study included (1) open versus closed static test chambers, (2) natural versus artificial diluent, (3) aerated versus nonaerated test solution, and (4) low versus medium energy water-accommodated (WAF) mixing energies. The use of tests using natural or artificial diluent showed no difference in either toxicity test or analytical chemistry results. Based on median lethal concentrations (LC50) of WAFs of unweathered oil (MASS), mysid tests performed in closed chambers were approximately 41 % lower than LC50 values from open-chamber studies, possibly a result of the presence of low-molecular weight volatile aromatics (i.e., naphthalenes). This research also showed that using a medium-energy WAF (with a 20–25 % vortex) increases the number of chemical components compared with low-energy WAF, thus affecting the composition of the exposure media and increasing toxicity. The comparison of toxic units as a measure of the potential toxicity of fresh and weathered oils showed that weathered oils (e.g., Juniper, CTC) are less toxic than the unweathered MASS oil. In the event of future oil spills, these variables should be considered to ensure that data regarding the potential toxicity and environmental risk are of good quality and reproducible.

  4. Acute toxicity of fire control chemicals to Daphnia magna (Straus) and Selenastrum capricornutum (Printz).

    PubMed

    McDonald, S F; Hamilton, S J; Buhl, K J; Heisinger, J F

    1996-02-01

    Acute toxicity tests were conducted exposing Daphnia magna Straus (daphnid) in soft and hard reconstituted waters (hardness 42 and 162 mg/liter as CaCO3, respectively), and Selenastrum capricornutum Printz (algae) in ASTM algal assay medium (hardness 15 mg/liter as CaCO3) to fire retardants Fire-Trol GTS-R, Fire-Trol LCG-R, and Phos-Chek D75-F, and foam suppressants Phos-Check WD-881 and Silv-Ex. The chemicals were slightly toxic to practically harmless to daphnids and moderately toxic to algae. Water quality did not consistently alter the toxicity of the test chemicals to daphnids. The most toxic chemical to daphnids was Silv-Ex (48-hr EC50 7 mg/liter in soft and hard waters), whereas the least toxic chemical to daphnids was Fire-Trol LCG-R (48-hr EC50 848 mg/liter in soft water, 813 mg/liter in hard water). The most toxic chemical to algae was Fire-Trol LCG-R (96-hr IC50 10 mg/liter), and the least toxic chemical was Phos-Chek D75-F (96-hr IC50 79 mg/liter). Un-ionized ammonia concentrations near the EC50 or IC50 value in tests with the Fire-Trol compounds were frequently equal to or above reported LC50 un-ionized ammonia concentrations. Un-ionized ammonia concentrations in tests with Phos-Chek D75-F were low, thus other toxic components present in the compounds probably contributed to the toxicity. When compared to the daphnids tested in ASTM soft water, the Fire-Trol compounds were most toxic to algae, whereas Phos-Chek D75-F and the foam suppressants were most toxic to daphnids. The results of these tests are comparable to those obtained from research conducted in other laboratories with the same species and similar chemicals. Accidental entry of fire-fighting chemicals into aquatic environments could adversely affect algae and aquatic invertebrates, thus disrupting ecosystem function.

  5. Acute toxicity of fire control chemicals to Daphnia magna(Straus) and Selenastrum capricornutum(Printz)

    USGS Publications Warehouse

    McDonald, Susan F.; Hamilton, Steven J.; Buhl, Kevin J.; Heisinger, James F.

    1996-01-01

    Acute toxicity tests were conducted exposingDaphnia magnaStraus (daphnid) in soft and hard reconstituted waters (hardness 42 and 162 mg/liter as CaCO3, respectively), andSelenastrum capricornutumPrintz (algae) in ASTM algal assay medium (hardness 15 mg/liter as CaCO3) to fire retardants Fire-Trol GTS-R, Fire-Trol LCG-R, and Phos-Chek D75-F, and foam suppressants Phos-Chek WD-881 and Silv-Ex. The chemicals were slightly toxic to practically harmless to daphnids and moderately toxic to algae. Water quality did not consistently alter the toxicity of the test chemicals to daphnids. The most toxic chemical to daphnids was Silv-Ex (48-hr EC507 mg/liter in soft and hard waters), whereas the least toxic chemical to daphnids was Fire-Trol LCG-R (48-hr EC50848 mg/liter in soft water, 813 mg/liter in hard water). The most toxic chemical to algae was Fire-Trol LCG-R (96-hr IC5010 mg/liter), and the least toxic chemical was Phos-Chek D75-F (96-hr IC5079 mg/liter). Un-ionized ammonia concentrations near the EC50or IC50value in tests with the Fire-Trol compounds were frequently equal to or above reported LC50un-ionized ammonia concentrations. Un-ionized ammonia concentrations in tests with Phos-Chek D75-F were low, thus other toxic components present in the compounds probably contributed to the toxicity. When compared to the daphnids tested in ASTM soft water, the Fire-Trol compounds were most toxic to algae, whereas Phos-Chek D75-F and the foam suppressants were most toxic to daphnids. The results of these tests are comparable to those obtained from research conducted in other laboratories with the same species and similar chemicals. Accidental entry of fire-fighting chemicals into aquatic environments could adversely affect algae and aquatic invertebrates, thus disrupting ecosystem function.

  6. Feasibility and Acute Toxicity of Hypofractionated Radiation in Large-breasted Patients

    SciTech Connect

    Dorn, Paige L.; Corbin, Kimberly S.; Al-Hallaq, Hania; Hasan, Yasmin; Chmura, Steven J.

    2012-05-01

    Purpose: To determine the feasibility of and acute toxicity associated with hypofractionated whole breast radiation (HypoRT) after breast-conserving surgery in patients excluded from or underrepresented in randomized trials comparing HypoRT with conventional fractionation schedules. Methods and Materials: A review was conducted of all patients consecutively treated with HypoRT at University of Chicago. All patients were treated to 42.56 Gy in 2.66 Gy daily fractions in either the prone or supine position. Planning was performed in most cases using wedges and large segments or a 'field-in-field' technique. Breast volume was estimated using volumetric measurements of the planning target volume (PTV). Dosimetric parameters of heterogeneity (V105, V107, V110, and maximum dose) were recorded for each treatment plan. Acute toxicity was scored for each treated breast. Results: Between 2006 and 2010, 78 patients were treated to 80 breasts using HypoRT. Most women were overweight or obese (78.7%), with a median body mass index of 29.2 kg/m{sup 2}. Median breast volume was 1,351 mL. Of the 80 treated breasts, the maximum acute skin toxicity was mild erythema or hyperpigmentation in 70.0% (56/80), dry desquamation in 21.25% (17/80), and focal moist desquamation in 8.75% (7/80). Maximum acute toxicity occurred after the completion of radiation in 31.9% of patients. Separation >25 cm was not associated with increased toxicity. Breast volume was the only patient factor significantly associated with moist desquamation on multivariable analysis (p = 0.01). Patients with breast volume >2,500 mL experienced focal moist desquamation in 27.2% of cases compared with 6.34% in patients with breast volume <2,500 mL (p = 0.03). Conclusions: HypoRT is feasible and safe in patients with separation >25 cm and in patients with large breast volume when employing modern planning and positioning techniques. We recommend counseling regarding expected increases in skin toxicity in women with a PTV

  7. Crosstalk between Zinc Status and Giardia Infection: A New Approach.

    PubMed

    Astiazarán-García, Humberto; Iñigo-Figueroa, Gemma; Quihui-Cota, Luis; Anduro-Corona, Iván

    2015-06-03

    Zinc supplementation has been shown to reduce the incidence and prevalence of diarrhea; however, its anti-diarrheal effect remains only partially understood. There is now growing evidence that zinc can have pathogen-specific protective effects. Giardiasis is a common yet neglected cause of acute-chronic diarrheal illness worldwide which causes disturbances in zinc metabolism of infected children, representing a risk factor for zinc deficiency. How zinc metabolism is compromised by Giardia is not well understood; zinc status could be altered by intestinal malabsorption, organ redistribution or host-pathogen competition. The potential metal-binding properties of Giardia suggest unusual ways that the parasite may interact with its host. Zinc supplementation was recently found to reduce the rate of diarrhea caused by Giardia in children and to upregulate humoral immune response in Giardia-infected mice; in vitro and in vivo, zinc-salts enhanced the activity of bacitracin in a zinc-dose-dependent way, and this was not due to zinc toxicity. These findings reflect biological effect of zinc that may impact significantly public health in endemic areas of infection. In this paper, we shall explore one direction of this complex interaction, discussing recent information regarding zinc status and its possible contribution to the outcome of the encounter between the host and Giardia.

  8. Crosstalk between Zinc Status and Giardia Infection: A New Approach

    PubMed Central

    Astiazarán-García, Humberto; Iñigo-Figueroa, Gemma; Quihui-Cota, Luis; Anduro-Corona, Iván

    2015-01-01

    Zinc supplementation has been shown to reduce the incidence and prevalence of diarrhea; however, its anti-diarrheal effect remains only partially understood. There is now growing evidence that zinc can have pathogen-specific protective effects. Giardiasis is a common yet neglected cause of acute-chronic diarrheal illness worldwide which causes disturbances in zinc metabolism of infected children, representing a risk factor for zinc deficiency. How zinc metabolism is compromised by Giardia is not well understood; zinc status could be altered by intestinal malabsorption, organ redistribution or host-pathogen competition. The potential metal-binding properties of Giardia suggest unusual ways that the parasite may interact with its host. Zinc supplementation was recently found to reduce the rate of diarrhea caused by Giardia in children and to upregulate humoral immune response in Giardia-infected mice; in vitro and in vivo, zinc-salts enhanced the activity of bacitracin in a zinc-dose-dependent way, and this was not due to zinc toxicity. These findings reflect biological effect of zinc that may impact significantly public health in endemic areas of infection. In this paper, we shall explore one direction of this complex interaction, discussing recent information regarding zinc status and its possible contribution to the outcome of the encounter between the host and Giardia. PMID:26046395

  9. Soil factors controlling the toxicity of copper and zinc to microbial processes in Australian soils.

    PubMed

    Broos, Kris; Warne, Michael St J; Heemsbergen, Diane A; Stevens, Daryl; Barnes, Mary B; Correll, Raymond L; McLaughlin, Mike J

    2007-04-01

    Abstract-Two soil microbial processes, substrate-induced nitrification (SIN) and substrate-induced respiration (SIR), were measured in the topsoils of 12 Australian field trials that were amended separately with increasing concentrations of ZnSO4 or CuSO4. The median effect concentration (EC50) values for Zn and Cu based on total metal concentrations varied between 107 and 8,298 mg kg(-1) for Zn and 108 and 2,155 mg kg(-1) Cu among soils. The differences in both Zn and Cu toxicity across the 12 soils were not explained by either the soil solution metal concentrations or CaCl2-extractable metal concentrations, because the variation in the EC50 values was larger than those using total concentrations. Toxicity of Zn and Cu decreased with increasing soil pH for SIN. For Cu, also increasing cation exchange capacity (CEC) and percent clay decreased the toxicity towards SIN. In contrast to SIN, soil pH had no significant effect on toxicity values of SIR. Significant relationships were found between the EC50 values for SIR and background Zn and CEC for Zn, and percent clay and log CEC for Cu. Relationships such as those developed in this study will permit Australian environmental regulation to move from single-value national soil quality guidelines to soil-specific quality guidelines and permit soil-specific risk assessments to be undertaken.

  10. Evaluation of the detoxication efficiencies for acrylonitrile wastewater treated by a combined anaerobic oxic-aerobic biological fluidized tank (A/O-ABFT) process: Acute toxicity and zebrafish embryo toxicity.

    PubMed

    Na, Chunhong; Zhang, Ying; Deng, Minjie; Quan, Xie; Chen, Shuo; Zhang, Yaobin

    2016-07-01

    Acrylonitrile (ACN) wastewater generated during ACN production has been reported to be toxic to many aquatic organisms. However, few studies have evaluated toxicity removal of ACN wastewater during and after the treatment process. In this study, the detoxication ability of an ACN wastewater treatment plant (WWTP) was evaluated using Daphnia magna, Danio rerio and zebrafish embryo. This ACN WWTP has a combined anaerobic oxic-aerobic biological fluidized tank (A/O-ABFT) process upgraded from the traditional anaerobic oxic (A/O) process. Moreover, the potential toxicants of the ACN wastewaters were identified by gas chromatography-mass spectrometry (GC-MS). The raw ACN wastewater showed high acute and embryo toxicity. 3-Cyanopyridine, succinonitrile and a series of nitriles were detected as the toxic contributors of ACN wastewater. The A/O process was effective for the acute and embryo toxicity removal, as well as the organic toxicants. However, the A/O effluent still showed acute and embryo toxicity which was attributed by the undegraded and the newly generated toxicants during the A/O process. The residual acute and embryo toxicity as well as the organic toxicants in the A/O effluent were further reduced after going through the downstream ABFT process system. The final effluent displayed no significant acute and embryo toxicity, and less organic toxicants were detected in the final effluent. The upgrade of this ACN WWTP results in the improved removal efficiencies for acute and embryo toxicity, as well as the organic toxicants.

  11. Influences of nanoparticle zinc oxide on acutely isolated rat hippocampal CA3 pyramidal neurons.

    PubMed

    Zhao, Jingxia; Xu, Lanju; Zhang, Tao; Ren, Guogang; Yang, Zhuo

    2009-03-01

    The effects of zinc oxide nanoparticles (nano-ZnO) on the properties of voltage-dependent sodium, potassium currents and evoked action potentials were studied in acutely isolated rat hippocampal CA3 pyramidal neurons at postnatal ages of 10-14 days rats using the whole-cell patch-clamp technique. The results indicated that: (1) in the present of final concentration of 10(-4)g/ml nano-ZnO, the current-voltage curve of sodium current (I(Na)) was decreased, and the peak amplitudes of I(Na) were increased considerably from -50 to +20mV (p<0.05). Meanwhile, the inactivation and the recovery from inactivation of I(Na) were also promoted by the nano-ZnO solution (10(-4)g/ml) (p<0.01). However, the steady-state activation curve of I(Na) was not shifted by the nano-ZnO. (2) The amplitudes of transient outward potassium current (I(A)) were increased by the nano-ZnO solution (10(-4)g/ml), while the current-voltage curve of delayed rectifier potassium current (I(K)) was significantly increased from +20 to +90mV (p<0.05). However, it is apparent that the nano-ZnO solution did not shift the steady-state activation curve of I(A) and I(K), and neither had significant effects on the inactivation and the recovery from inactivation of I(A). (3) Peak amplitude and overshoot of the evoked single action potential were increased and half-width was diminished in the presence of the 10(-4)g/ml nano-ZnO solution (p<0.05). Simultaneously, a prolonged depolarizing current injection enhanced (p<0.05) repetitive firing evoked firing rate. These results suggested that 10(-4)g/ml nano-ZnO solution can lead to an enhancement in the current amplitudes of I(Na) and I(K) by increasing the opening number of sodium channels, delaying rectifier potassium channels, and enhancing the excitability of neurons, which lead to Na(+) influx and the accumulation of intracellular Na(+), as well as K(+) efflux plus the loss of cytoplasmic K(+). These may disturb the ionic homeostasis and the physiological

  12. Cross-Linked Hyaluronan Gel Reduces the Acute Rectal Toxicity of Radiotherapy for Prostate Cancer

    SciTech Connect

    Wilder, Richard B.; Barme, Greg A.; Gilbert, Ronald F.; Holevas, Richard E.; Kobashi, Luis I.; Reed, Richard R.; Solomon, Ronald S.; Walter, Nancy L.; Chittenden, Lucy; Mesa, Albert V.; Agustin, Jeffrey; Lizarde, Jessica; Macedo, Jorge; Ravera, John; Tokita, Kenneth M.

    2010-07-01

    Purpose: To prospectively analyze whether cross-linked hyaluronan gel reduces the mean rectal dose and acute rectal toxicity of radiotherapy for prostate cancer. Methods and Materials: Between September 2008 and March 2009, we transperitoneally injected 9mL of cross-linked hyaluronan gel (Hylaform; Genzyme Corporation, Cambridge, MA) into the anterior perirectal fat of 10 early-stage prostate cancer patients to increase the separation between the prostate and rectum by 8 to 18mm at the start of radiotherapy. Patients then underwent high-dose rate brachytherapy to 2,200cGy followed by intensity-modulated radiation therapy to 5,040cGy. We assessed acute rectal toxicity using the National Cancer Institute Common Terminology Criteria for Adverse Events v3.0 grading scheme. Results: Median follow-up was 3 months. The anteroposterior dimensions of Hylaform at the start and end of radiotherapy were 13 {+-} 3mm (mean {+-} SD) and 10 {+-} 4mm, respectively. At the start of intensity-modulated radiation therapy, daily mean rectal doses were 73 {+-} 13cGy with Hylaform vs. 106 {+-} 20cGy without Hylaform (p = 0.005). There was a 0% incidence of National Cancer Institute Common Terminology Criteria for Adverse Events v3.0 Grade 1, 2, or 3 acute diarrhea in 10 patients who received Hylaform vs. a 29.7% incidence (n = 71) in 239 historical controls who did not receive Hylaform (p = 0.04). Conclusions: By increasing the separation between the prostate and rectum, Hylaform decreased the mean rectal dose. This led to a significant reduction in the acute rectal toxicity of radiotherapy for prostate cancer.

  13. Influence of soil pH on the toxicity of zinc oxide nanoparticles to the terrestrial isopod Porcellionides pruinosus.

    PubMed

    Tourinho, Paula S; van Gestel, Cornelis A M; Lofts, Stephen; Soares, Amadeu M V M; Loureiro, Susana

    2013-12-01

    The effects of soil pH on the toxicity of ZnO nanoparticles (NPs) to the terrestrial isopod Porcellionides pruinosus were evaluated. Isopods were exposed to a natural soil amended with CaCO3 to reach 3 different pH(CaCl2) levels (4.5, 6.2, and 7.3) and to standard LUFA 2.2 soil (pH 5.5) spiked with ZnO NPs (30 nm), non-nano ZnO (200 nm), and ionic Zn as ZnCl₂. Toxicity was expressed based on total Zn concentration in soil, as well as total Zn and free Zn²⁺ ion concentrations in porewater. Compared with ZnO-spiked soils, the ZnCl₂-spiked soils had lower pH and higher porewater Ca²⁺ and Zn levels. Isopod survival did not differ between Zn forms and soils, but survival was higher for isopods exposed to ZnO NPs at pH 4.5. Median effect concentrations (EC50s) for biomass change showed similar trends for all Zn forms in all soils, with higher values at intermediate pH. Median lethal concentration (LC50) and EC50 values based on porewater Zn or free Zn ion concentrations were much lower for ZnO than for ionic zinc. Zn body concentrations increased in a dose-related manner, but no effect of soil pH was found. It is suggested not only that dissolved or free Zn in porewater contributed to uptake and toxicity, but also that oral uptake (i.e., ingestion of soil particles) could be an important additional route of exposure.

  14. Beryllium metal I. experimental results on acute oral toxicity, local skin and eye effects, and genotoxicity.

    PubMed

    Strupp, Christian

    2011-01-01

    The toxicity of soluble metal compounds is often different from that of the parent metal. Since no reliable data on acute toxicity, local effects, and mutagenicity of beryllium metal have ever been generated, beryllium metal powder was tested according to the respective Organisation for Economical Co-Operation and Development (OECD) guidelines. Acute oral toxicity of beryllium metal was investigated in rats and local effects on skin and eye in rabbits. Skin-sensitizing properties were investigated in guinea pigs (maximization method). Basic knowledge about systemic bioavailability is important for the design of genotoxicity tests on poorly soluble substances. Therefore, it was necessary to experimentally compare the capacities of beryllium chloride and beryllium metal to form ions under simulated human lung conditions. Solubility of beryllium metal in artificial lung fluid was low, while solubility in artificial lysosomal fluid was moderate. Beryllium chloride dissolution kinetics were largely different, and thus, metal extracts were used in the in vitro genotoxicity tests. Genotoxicity was investigated in vitro in a bacterial reverse mutagenicity assay, a mammalian cell gene mutation assay, a mammalian cell chromosome aberration assay, and an unscheduled DNA synthesis (UDS) assay. In addition, cell transformation was tested in a Syrian hamster embryo cell assay, and potential inhibition of DNA repair was tested by modification of the UDS assay. Beryllium metal was found not to be mutagenic or clastogenic based on the experimental in vitro results. Furthermore, treatment with beryllium metal extracts did not induce DNA repair synthesis, indicative of no DNA-damaging potential of beryllium metal. A cell-transforming potential and a tendency to inhibit DNA repair when the cell is severely damaged by an external stimulus were observed. Beryllium metal was also found not to be a skin or eye irritant, not to be a skin sensitizer, and not to have relevant acute oral

  15. Beryllium Metal I. Experimental Results on Acute Oral Toxicity, Local Skin and Eye Effects, and Genotoxicity

    PubMed Central

    Strupp, Christian

    2011-01-01

    The toxicity of soluble metal compounds is often different from that of the parent metal. Since no reliable data on acute toxicity, local effects, and mutagenicity of beryllium metal have ever been generated, beryllium metal powder was tested according to the respective Organisation for Economical Co-Operation and Development (OECD) guidelines. Acute oral toxicity of beryllium metal was investigated in rats and local effects on skin and eye in rabbits. Skin-sensitizing properties were investigated in guinea pigs (maximization method). Basic knowledge about systemic bioavailability is important for the design of genotoxicity tests on poorly soluble substances. Therefore, it was necessary to experimentally compare the capacities of beryllium chloride and beryllium metal to form ions under simulated human lung conditions. Solubility of beryllium metal in artificial lung fluid was low, while solubility in artificial lysosomal fluid was moderate. Beryllium chloride dissolution kinetics were largely different, and thus, metal extracts were used in the in vitro genotoxicity tests. Genotoxicity was investigated in vitro in a bacterial reverse mutagenicity assay, a mammalian cell gene mutation assay, a mammalian cell chromosome aberration assay, and an unscheduled DNA synthesis (UDS) assay. In addition, cell transformation was tested in a Syrian hamster embryo cell assay, and potential inhibition of DNA repair was tested by modification of the UDS assay. Beryllium metal was found not to be mutagenic or clastogenic based on the experimental in vitro results. Furthermore, treatment with beryllium metal extracts did not induce DNA repair synthesis, indicative of no DNA-damaging potential of beryllium metal. A cell-transforming potential and a tendency to inhibit DNA repair when the cell is severely damaged by an external stimulus were observed. Beryllium metal was also found not to be a skin or eye irritant, not to be a skin sensitizer, and not to have relevant acute oral

  16. Carbon ion therapy for advanced sinonasal malignancies: feasibility and acute toxicity

    PubMed Central

    2011-01-01

    Purpose To evaluate feasibility and toxicity of carbon ion therapy for treatment of sinonasal malignancies. First site of treatment failure in malignant tumours of the paranasal sinuses and nasal cavity is mostly in-field, local control hence calls for dose escalation which has so far been hampered by accompanying acute and late toxicity. Raster-scanned carbon ion therapy offers the advantage of sharp dose gradients promising increased dose application without increase of side-effects. Methods Twenty-nine patients with various sinonasal malignancies were treated from 11/2009 to 08/2010. Accompanying toxicity was evaluated according to CTCAE v.4.0. Tumor response was assessed according to RECIST. Results Seventeen patients received treatment as definitive RT, 9 for local relapse, 2 for re-irradiation. All patients had T4 tumours (median CTV1 129.5 cc, CTV2 395.8 cc), mostly originating from the maxillary sinus. Median dose was 73 GyE mostly in mixed beam technique as IMRT plus carbon ion boost. Median follow- up was 5.1 months [range: 2.4 - 10.1 months]. There were 7 cases with grade 3 toxicity (mucositis, dysphagia) but no other higher grade acute reactions; 6 patients developed grade 2 conjunctivits, no case of early visual impairment. Apart from alterations of taste, all symptoms had resolved at 8 weeks post RT. Overall radiological response rate was 50% (CR and PR). Conclusion Carbon ion therapy is feasible; despite high doses, acute reactions were not increased and generally resolved within 8 weeks post radiotherapy. Treatment response is encouraging though follow-up is too short to estimate control rates or evaluate potential late effects. Controlled trials are warranted. PMID:21466696

  17. The acute and chronic toxicity of major geochemical ions to Hyalella azteca Ion interactions and comparisons to other species

    EPA Science Inventory

    We have previously reported that the acute and chronic toxicities of major geochemical ions (Na, K, Ca, Mg, Cl, SO4, HCO3) to Ceriodaphnia dubia can involve multiple, independent mechanisms. The toxicities of K, Mg, and Ca salts were best related to the chemical activity of the c...

  18. Web-based Interspecies Correlation Estimation (Web-ICE) for Acute Toxicity: User Manual Version 3.3

    EPA Science Inventory

    Information on the acute toxicity to multiple species is needed for the assessment of the risks to, and the protection of, individuals, populations, and ecological communities. However, toxicity data are limited for the majority of species, while standard test species are general...

  19. Acute toxicity of firefighting chemical formulations to four life stages of fathead minnow.

    PubMed

    Gaikowski, M P; Hamilton, S J; Buhl, K J; McDonald, S F; Summers, C H

    1996-08-01

    Laboratory studies were conducted with four early life stages of fathead minnow, Pimephales promelas, to determine the acute toxicity of five firefighting chemical formulations in standardized soft and hard water. Egg, fry, 30-day posthatch, and 60-day posthatch life stages were tested with three fire retardants (Fire-Trol GTS-R, Fire-Trol LCG-R, and Phos-Chek D75-F) and two fire-suppressant foams (Phos-Chek WD-881 and Ansul Silv-Ex). Fry were generally the most sensitive life stage tested, whereas the eggs were the least sensitive life stage. Formulation toxicity was greater in hard water than in soft water for all life stages tested. Fire-suppressant foams were more toxic than the fire retardants. The 96-hr LC50s derived for fathead minnows were rank ordered from the most toxic to the least toxic formulation as follows: Phos-Chek WD-881 (13-32 mg/liter) > Silv-Ex (19-32 mg/liter) > Fire-Trol GTS-R (135-787 mg/liter) > Phos-Chek D75-F (168-2250 mg/liter) > Fire-Trol LCG-R (519-6705 mg/liter) (ranges are the lowest and highest 96-hr LC50 for each formulation).

  20. Acute toxicity of firefighting chemical formulations to four life stages of fathead minnow

    USGS Publications Warehouse

    Gaikowski, Mark P.; Hamilton, Steve J.; Buhl, Kevin J.; McDonald, Susan F.; Summers, Cliff H.

    1996-01-01

    Laboratory studies were conducted with four early life stages of fathead minnow,Pimephales promelas,to determine the acute toxicity of five firefighting chemical formulations in standardized soft and hard water. Egg, fry, 30-day posthatch, and 60-day posthatch life stages were tested with three fire retardants (Fire-Trol GTS-R, Fire-Trol LCG-R, and Phos-Chek D75-F) and two fire-suppressant foams (Phos-Chek WD-881 and Ansul Silv-Ex). Fry were generally the most sensitive life stage tested, whereas the eggs were the least sensitive life stage. Formulation toxicity was greater in hard water than in soft water for all life stages tested. Fire-suppressant foams were more toxic than the fire retardants. The 96-hr LC50s derived for fathead minnows were rank ordered from the most toxic to the least toxic formulation as follows: Phos-Chek WD-881 (13a??32 mg/liter) > Silv-Ex (19a??32 mg/liter) > Fire-Trol GTS-R (135a??787 mg/liter) > Phos-Chek D75-F (168a??2250 mg/liter) > Fire-Trol LCG-R (519a??6705 mg/liter) (ranges are the lowest and highest 96-hr LC50for each formulation). (C) 1996 Academic Press, Inc.

  1. Evaluation of acute bioassays for assessing toxicity of polychlorinated biphenyl-contaminated soils

    SciTech Connect

    Hose, J.E.; Barlow, L.A.; Bent, S.; Elseewi, A.A.; Cliath, M.; Resketo, M.; Doyle, C.

    1986-03-01

    Proposed State of California regulations use fish toxicity information as one criterion in municipal or industrial waste hazard evaluation. Static 96-hr bioassays were performed using fathead minnows (Pimephales promelas), blacksmith (Chromis punctipinnis), and glass shrimp (Palaemonetes kadiakensis) exposed to soil experimentally contaminated with up to 500 ppm polychlorinated biphenyl (PCB) capacitor fluid added at a concentration of 500 mg liter-1. Other bioassays were conducted with a 6-day mixing period prior to the bioassay or with acetone added to solubilize the PCBs. No mortality attributable to PCB toxicity was observed in definitive bioassays using the two fish and one invertebrate species. PCB levels leached from soil containing 500 ppm Aroclor 1242 ranged from less than 0.6 to 3.4 ppb in freshwater tests to 3.5 ppb in seawater bioassays. Using these data as the basis for waste classification, soils contaminated with up to 500 ppb PCBs during capacitor spills would be designated nonhazardous. PCBs are known to be environmentally persistent and to bioaccumulate. Acute toxicity tests, therefore, do not adequately evaluate the general toxicity of PCB-contaminated soils. Hazardous waste regulations for hydrophobic compounds such as PCBs should instead be based upon chronic toxicity data and should also consider bioaccumulation potential.

  2. Evaluation of acute bioassays for assessing toxicity of polychlorinated biphenyl-contaminated soils.

    PubMed

    Hose, J E; Barlow, L A; Bent, S; Elseewi, A A; Cliath, M; Resketo, M; Doyle, C

    1986-03-01

    Proposed State of California regulations use fish toxicity information as one criterion in municipal or industrial waste hazard evaluation. Static 96-hr bioassays were performed using fathead minnows (Pimephales promelas), blacksmith (Chromis punctipinnis), and glass shrimp (Palaemonetes kadiakensis) exposed to soil experimentally contaminated with up to 500 ppm polychlorinated biphenyl (PCB) capacitor fluid added at a concentration of 500 mg liter-1. Other bioassays were conducted with a 6-day mixing period prior to the bioassay or with acetone added to solubilize the PCBs. No mortality attributable to PCB toxicity was observed in definitive bioassays using the two fish and one invertebrate species. PCB levels leached from soil containing 500 ppm Aroclor 1242 ranged from less than 0.6 to 3.4 ppb in freshwater tests to 3.5 ppb in seawater bioassays. Using these data as the basis for waste classification, soils contaminated with up to 500 ppb PCBs during capacitor spills would be designated nonhazardous. PCBs are known to be environmentally persistent and to bioaccumulate. Acute toxicity tests, therefore, do not adequately evaluate the general toxicity of PCB-contaminated soils. Hazardous waste regulations for hydrophobic compounds such as PCBs should instead be based upon chronic toxicity data and should also consider bioaccumulation potential.

  3. Intra- and interlaboratory variability in acute toxicity tests with glochidia and juveniles of freshwater mussels (Unionidae)

    USGS Publications Warehouse

    Wang, N.; Augspurger, T.; Barnhart, M.C.; Bidwell, Joseph R.; Cope, W.G.; Dwyer, F.J.; Geis, S.; Greer, I.E.; Ingersoll, C.G.; Kane, C.M.; May, T.W.; Neves, R.J.; Newton, T.J.; Roberts, A.D.; Whites, D.W.

    2007-01-01

    The present study evaluated the performance and variability in acute toxicity tests with glochidia and newly transformed juvenile mussels using the standard methods outlined in American Society for Testing and Materials (ASTM). Multiple 48-h toxicity tests with glochidia and 96-h tests with juvenile mussels were conducted within a single laboratory and among five laboratories. All tests met the test acceptability requirements (e.g., ???90% control survival). Intralaboratory tests were conducted over two consecutive mussel-spawning seasons with mucket (Actinonaias ligamentina) or fatmucket (Lampsilis siliquoidea) using copper, ammonia, or chlorine as a toxicant. For the glochidia of both species, the variability of intralaboratory median effective concentrations (EC50s) for the three toxicants, expressed as the coefficient of variation (CV), ranged from 14 to 27% in 24-h exposures and from 13 to 36% in 48-h exposures. The intralaboratory CV of copper EC50s for juvenile fatmucket was 24% in 48-h exposures and 13% in 96-h exposures. Interlaboratory tests were conducted with fatmucket glochidia and juveniles by five laboratories using copper as a toxicant. The interlaboratory CV of copper EC50s for glochidia was 13% in 24-h exposures and 24% in 48-h exposures, and the interlaboratory CV for juveniles was 22% in 48-h exposures and 42% in 96-h exposures. The high completion success and the overall low variability in test results indicate that the test methods have acceptable precision and can be performed routinely. ?? 2007 SETAC.

  4. Acute toxicity of copper, ammonia, and chlorine to glochidia and juveniles of freshwater mussels (Unionidae)

    USGS Publications Warehouse

    Wang, N.; Ingersoll, C.G.; Hardesty, D.K.; Ivey, C.D.; Kunz, J.L.; May, T.W.; Dwyer, F.J.; Roberts, A.D.; Augspurger, T.; Kane, C.M.; Neves, R.J.; Barnhart, M.C.

    2007-01-01

    The objective of the present study was to determine acute toxicity of copper, ammonia, or chlorine to larval (glochidia) and juvenile mussels using the recently published American Society for Testing and Materials (ASTM) Standard guide for conducting laboratory toxicity tests with freshwater mussels. Toxicity tests were conducted with glochidia (24- to 48-h exposures) and juveniles (96-h exposures) of up to 11 mussel species in reconstituted ASTM hard water using copper, ammonia, or chlorine as a toxicant. Copper and ammonia tests also were conducted with five commonly tested species, including cladocerans (Daphnia magna and Ceriodaphnia dubia; 48-h exposures), amphipod (Hyalella azteca; 48-h exposures), rainbow trout (Oncorhynchus mykiss; 96-h exposures), and fathead minnow (Pimephales promelas; 96-h exposures). Median effective concentrations (EC50s) for commonly tested species were >58 ??g Cu/L (except 15 ??g Cu/L for C. dubia) and >13 mg total ammonia N/L, whereas the EC50s for mussels in most cases were 40 ??g/L and above the FAV in the WQC for chlorine. The results indicate that the early life stages of mussels generally were more sensitive to copper and ammonia than other organisms and that, including mussel toxicity data in a revision to the WQC, would lower the WQC for copper or ammonia. Furthermore, including additional mussel data in 2007 WQC for copper based on biotic ligand model would further lower the WQC. ?? 2007 SETAC.

  5. Acute toxicity and aqueous solubility of some condensed thiophenes and their microbial metabolites

    SciTech Connect

    Seymour, D.T.; Hrudey, S.E.; Fedorak, P.M.; Verbeek, A.G.

    1997-04-01

    Petroleum or creosote contamination of surface waters, soils, or groundwaters introduces countless aromatic compounds to these environments. Among these are condensed thiophenes that were shown to be oxidized to sulfoxides, sulfones, and 2,3-diones by microbial cultures. In this study, the acute toxicities of 12 compounds (benzothiophene, benzothiophene sulfone, benzothiophene-2,3-diones, dibenzothiophene, dibenzothiophene sulfoxide, and dibenzothiophene sulfone) were determined by the Microtox{reg_sign} and Daphnia magna bioassays. To aid in determining the toxicities, the solubilities of many of these compounds were determined, which showed that the oxidized compounds were much more water soluble than the parent thiophenes. In nearly every case, the oxidized compounds were less toxic than their parent thiophenes. The Microtox method was more sensitive than the D. magna bioassay, but in general, there was a good correlation between toxicities measured by the two tests. Samples were removed from batch cultures of a Pseudomonas strain capable of oxidizing the thiophenes, and these samples were subjected to Microtox bioassays. These experiments showed that the toxicities of the culture supernatants decreased with incubation time.

  6. Proton Therapy for Spinal Ependymomas: Planning, Acute Toxicities, and Preliminary Outcomes

    SciTech Connect

    Amsbaugh, Mark J.; Grosshans, David R.; McAleer, Mary Frances; Zhu, Ron; Wages, Cody; Crawford, Cody N.; Palmer, Matthew; De Gracia, Beth; Woo Shiao; Mahajan, Anita

    2012-08-01

    Purpose: To report acute toxicities and preliminary outcomes for pediatric patients with ependymomas of the spine treated with proton beam therapy at the MD Anderson Cancer Center. Methods and Materials: Eight pediatric patients received proton beam irradiation between October 2006 and September 2010 for spinal ependymomas. Toxicity data were collected weekly during radiation therapy and all follow-up visits. Toxicities were graded according to the Common Terminology Criteria for Adverse Events version 3.0. Results: All patients had surgical resection of the tumor before irradiation (7 subtotal resection and 1 gross total resection). Six patients had World Health Organization Grade I ependymomas, and two had World Health Organization Grade II ependymomas. Patients had up to 3 surgical interventions before radiation therapy (range, 1-3; median, 1). Three patients received proton therapy after recurrence and five as part of their primary management. The entire vertebral body was treated in all but 2 patients. The mean radiation dose was 51.1 cobalt gray equivalents (range, 45 to 54 cobalt gray equivalents). With a mean follow-up of 26 months from the radiation therapy start date (range, 7-51 months), local control, event-free survival, and overall survival rates were all 100%. The most common toxicities during treatment were Grade 1 or 2 erythema (75%) and Grade 1 fatigue (38%). No patients had a Grade 3 or higher adverse event. Proton therapy dramatically reduced dose to all normal tissues anterior to the vertebral bodies in comparison to photon therapy. Conclusion: Preliminary outcomes show the expected control rates with favorable acute toxicity profiles. Proton beam therapy offers a powerful treatment option in the pediatric population, where adverse events related to radiation exposure are of concern. Extended follow-up will be required to assess for late recurrences and long-term adverse effects.

  7. Genotoxicity and acute and subchronic toxicity studies of a standardized methanolic extract of Ficus deltoidea leaves

    PubMed Central

    Farsi, Elham; Shafaei, Armaghan; Hor, Sook Yee; Khadeer Ahamed, Mohamed B.; Yam, Mun Fei; Asmawi, Mohd Z.; Ismail, Zhari

    2013-01-01

    OBJECTIVE: Ficus deltoidea leaves have been used in traditional medicine in Southeast Asia to treat diabetes, inflammation, diarrhea, and infections. The present study was conducted to assess the genotoxicity and acute and subchronic toxicity of a standardized methanol extract of F. deltoidea leaves. METHODS: Sprague Dawley rats were orally treated with five different single doses of the extract and screened for signs of toxicity for two weeks after administration. In the subchronic study, three different doses of the extract were administered for 28 days. Mortality, clinical signs, body weight changes, hematological and biochemical parameters, gross findings, organ weights, and histological parameters were monitored during the study. Genotoxicity was assessed using the Ames test with the TA98 and TA100 Salmonella typhimurium strains. Phytochemical standardization was performed using a colorimeter and high-performance liquid chromatography. Heavy metal detection was performed using an atomic absorption spectrometer. RESULTS: The acute toxicity study showed that the LD50 of the extract was greater than 5000 mg/kg. In the subchronic toxicity study, there were no significant adverse effects on food consumption, body weight, organ weights, mortality, clinical chemistry, hematology, gross pathology, or histopathology. However, a dose-dependent increase in the serum urea level was observed. The Ames test revealed that the extract did not have any potential to induce gene mutations in S. typhimurium, either in the presence or absence of S9 activation. Phytochemical analysis of the extract revealed high contents of phenolics, flavonoids, and tannins. High-performance liquid chromatography analysis revealed high levels of vitexin and isovitexin in the extract, and the levels of heavy metals were below the toxic levels. CONCLUSION: The no-observed adverse effect level of F. deltoidea in rats was determined to be 2500 mg/kg. PMID:23778480

  8. Predicting acute aquatic toxicity of structurally diverse chemicals in fish using artificial intelligence approaches.

    PubMed

    Singh, Kunwar P; Gupta, Shikha; Rai, Premanjali

    2013-09-01

    The research aims to develop global modeling tools capable of categorizing structurally diverse chemicals in various toxicity classes according to the EEC and European Community directives, and to predict their acute toxicity in fathead minnow using set of selected molecular descriptors. Accordingly, artificial intelligence approach based classification and regression models, such as probabilistic neural networks (PNN), generalized regression neural networks (GRNN), multilayer perceptron neural network (MLPN), radial basis function neural network (RBFN), support vector machines (SVM), gene expression programming (GEP), and decision tree (DT) were constructed using the experimental toxicity data. Diversity and non-linearity in the chemicals' data were tested using the Tanimoto similarity index and Brock-Dechert-Scheinkman statistics. Predictive and generalization abilities of various models constructed here were compared using several statistical parameters. PNN and GRNN models performed relatively better than MLPN, RBFN, SVM, GEP, and DT. Both in two and four category classifications, PNN yielded a considerably high accuracy of classification in training (95.85 percent and 90.07 percent) and validation data (91.30 percent and 86.96 percent), respectively. GRNN rendered a high correlation between the measured and model predicted -log LC50 values both for the training (0.929) and validation (0.910) data and low prediction errors (RMSE) of 0.52 and 0.49 for two sets. Efficiency of the selected PNN and GRNN models in predicting acute toxicity of new chemicals was adequately validated using external datasets of different fish species (fathead minnow, bluegill, trout, and guppy). The PNN and GRNN models showed good predictive and generalization abilities and can be used as tools for predicting toxicities of structurally diverse chemical compounds.

  9. Acute embryo toxicity and teratogenicity of three potential biofuels also used as flavor or solvent.

    PubMed

    Bluhm, Kerstin; Seiler, Thomas-Benjamin; Anders, Nico; Klankermayer, Jürgen; Schaeffer, Andreas; Hollert, Henner

    2016-10-01

    The demand for biofuels increases due to concerns regarding greenhouse gas emissions and depletion of fossil oil reserves. Many substances identified as potential biofuels are solvents or already used as flavors or fragrances. Although humans and the environment may be readily exposed little is known regarding their (eco)toxicological effects. In this study, the three potential biofuels ethyl levulinate (EL), 2-methyltetrahydrofuran (2-MTHF) and 2-methylfuran (2-MF) were investigated for their acute embryo toxicity and teratogenicity using the fish embryo toxicity (FET) test to identify unknown hazard potentials and to allow focusing further research on substances with low toxic potentials. In addition, two fossil fuels (diesel and gasoline) and an established biofuel (rapeseed oil methyl ester) were investigated as references. The FET test is widely accepted and used in (eco)toxicology. It was performed using the zebrafish Danio rerio, a model organism useful for the prediction of human teratogenicity. Testing revealed a higher acute toxicity for EL (LC50: 83mg/L) compared to 2-MTHF (LC50: 2980mg/L), 2-MF (LC50: 405mg/L) and water accommodated fractions of the reference fuels including gasoline (LC50: 244mg DOC/L). In addition, EL caused a statistically significant effect on head development resulting in elevated head lengths in zebrafish embryos. Results for EL reduce its likelihood of use as a biofuel since other substances with a lower toxic potential are available. The FET test applied at an early stage of development might be a useful tool to avoid further time and money requiring steps regarding research on unfavorable biofuels.

  10. Acute intravenous infusion of disodium dihydrogen (1-hydroxyethylidene)diphosphonate: mechanism of toxicity.

    PubMed

    Francis, M D; Slough, C L

    1984-08-01

    The acute intravenous toxicity of disodium dihydrogen (1-hydroxyethylidene)diphosphonate (etidronate disodium; I) and the mechanism of this toxic response have been investigated in 40 beagle dogs. The intravenous toxicity of I is dependent on the total dose administered and the length of the infusion interval. The toxicity of I is directly related to the ability of the drug to bind or complex with the circulating calcium in the blood. Maximum depressions in ionized calcium coincide in time with peak blood levels of I, and at lethal doses electrocardiographic changes indicative of hypocalcemia are observed. For a 2-min infusion of 2 mg of I/kg, no effect is observed on ionized calcium levels, and the electrocardiogram remains normal. At doses of 16 and 32 mg/kg, coincident with an