Showing papers in "Archives of Environmental Contamination and Toxicology in 1987"
TL;DR: In a study of fall migrating juvenile and second-year Bonaparte's gulls (Larus Philadelphia) collected in the Quoddy region, no significant differences between sex differences were detected in Hg concentrations in primary feathers, pectoral muscle, brain, liver, and kidney tissues as mentioned in this paper.
Abstract: No significant between sex differences were detected in Hg concentrations in primary feathers, pectoral muscle, brain, liver, and kidney tissues of fall migrating juvenile and second-year Bonaparte's gulls (Larus Philadelphia) collected in the Quoddy region. Adults showed sexual differences only in the first 5 primary feathers, and in muscle, kidney and brain. Differences in Hg concentrations among age groups were reflected in the primary feathers and body tissues, but as the molt progressed, Hg concentrations decreased as they converged toward a minimum asymptotic Hg level for each tissue. This suggests that the body burden of Hg was reduced through its redistribution from the body tissues into the growing feathers. Mercury concentrations in premolt head feathers (pre-egg-laying) did not vary significantly between adult females and males, whereas Hg concentrations in postmolt feathers (post-egg-laying) were significantly lower in females, suggesting that egg-laying was also a route for Hg elimination. After the completion of the molt, the new feathers contained most of the body burden of Hg (93.0% in adults).
219 citations
TL;DR: Findings suggest that OC contamination is a major factor in the non-recovery of the St. Lawrence beluga population over the last decades.
Abstract: High levels of organochlorine chemicals (OC) were found in the blubber of 26 stranded carcasses of beluga whales from an isolated population in the St. Lawrence Estuary (Quebec, Canada). These compounds accumulated with age in both sexes, being consistently more concentrated in male tissue; high and variable concentrations were found in four juveniles. Lower levels in females are best explained through massive transfer to the newborn during lactation, resulting in juvenile OC concentrations equal to or higher than in adult males. Concentrations in the liver and kidney expressed on a lipid basis suggest dynamic OC exchange between tissues. The adipose tissue concentrations reported here were higher or equal to those found In some pinnipeds, in laboratory animals, and in domestic animals with severe reproductive failure. These findings suggest that OC contamination is a major factor in the non-recovery of the St. Lawrence beluga population over the last decades.
202 citations
TL;DR: A number of individual metabolites of aromatic compounds were found in the hydrolyzed bile of five English sole (Parophrys vetulus) captured from polluted sites in Puget Sound, Washington as discussed by the authors.
Abstract: A number of individual metabolites of aromatic compounds were found in the hydrolyzed bile of five English sole (Parophrys vetulus) captured from polluted sites in Puget Sound, Washington. Metabolites of fluorene, dibenzofuran, phenanthrene, fluoranthene, pyrene and benzo-[a]pyrene (BaP) were tentatively identified by gas chromatography/mass spectrometry (GC/MS) or by high-pressure liquid chromatography (HPLC) with fluorescence detection. Identifications of these metabolites were confirmed by comparing their fluorescence excitation/emission and mass spectra to those obtained from metabolites produced after other English sole from a reference site were injected with individual parent aromatic compounds. High concentrations of many of the individual metabolites quantitated (up to 300,000 ng/g) were found in the hydrolyzed bile of sole sampled from polluted sites. None of these metabolites were found in bile of sole sampled from a relatively clean (reference) site in Puget Sound.
177 citations
TL;DR: Cormorants, guillemots and eiders, who feed on benthic organisms, and common terns, which feed predominantly on fish, had the highest tissue Hg levels, whereas birds such as kittiwakes and phalaropes, which consume mainly pelagic invertebrates, hadThe lowest Hg Levels.
Abstract: Total mercury (Hg) concentrations were analyzed for tissues of nine species of marine birds from the Quoddy region, New Brunswick, Canada, including cormorants (Phalacrocorax auritus), eiders (Somateria mollissima), guillemots (Cepphus grylle), phalaropes (Phalaropus lobatus), gulls (Larus argentatus, L. Philadelphia), terns (Sterna hirundo, S. paradisaea) and kittiwakes (Rissa tridactyla). There was a progressive decrease in Hg concentration from the innermost to the outermost primary feather in Bonaparte's gulls, herring gulls, black-legged kittiwakes and Arctic terns. Primaries of common terns and black guillemots showed no significant trend. Cormorants, guillemots and eiders, which feed on benthic organisms, and common terns, which feed predominantly on fish, had the highest tissue Hg levels, whereas birds such as kittiwakes and phalaropes, which consume mainly pelagic invertebrates, had the lowest Hg levels.
177 citations
TL;DR: The elevated levels of selenium measured in forage organisms from Kesterson are probably toxic to sensitive consumer animals, and may explain recent observations of dead and deformed embryos in eggs of aquatic birds that nest at the Reservoir.
Abstract: Concentrations of total selenium were high in 1983 in water, sediment, organic detritus, aquatic plants and invertebrates, and mosquitofish (Gambusia affinis) from Kesterson Reservoir (San Joaquin Valley, California) and the San Luis Drain. Selenium concentrations in biota from the Reservoir and Drain (referred to here collectively as “Kesterson”) exceeded 300 (μg/g dry weight in some samples of algae, submerged rooted plants, chironomids, and mosquitofish, and were as high as 440 μg/g dry weight in decomposing detritus. Overall, selenium concentrations in samples from Kesterson averaged about 100-fold higher than those from the Volta Wildlife Area (here termed “Volta”), a nearby site that does not receive subsurface drainage water. Selenium concentrations generally increased from water to sediment to plants to animals. Spatial (geographic) patterns were observed for selenium concentrations in samples from Kesterson, but not in those from Volta. Higher concentrations were usually measured in samples from the San Luis Drain than from the evaporation ponds that comprise Kesterson Reservoir. At Kesterson, concentrations were usually higher in August than in May. The elevated levels of selenium measured in forage organisms from Kesterson are probably toxic to sensitive consumer animals, and may explain recent observations of dead and deformed embryos in eggs of aquatic birds that nest at the Reservoir. The effects of the selenium on fish living in subsurface agricultural drainage water are still poorly understood.
161 citations
TL;DR: It is shown that the results of sperm bioassays can be affected by a number of factors including temperature, pH, salinity, sperm:egg ratios, sperm exposure times, test materials, and echinoid species.
Abstract: A simple sperm/fertilization bioassay, primarily using sea urchin (and sand dollar) gametes, was improved to yield a quick, sensitive, and cost-effective procedure for measuring toxicity in marine waters. Standard sperm bioassays are conducted by exposing sperm cells to test solutions for 60 min prior to addition of eggs to the test solution for fertilization. Reduced fertilization success (as indicated by the presence or absence of the obvious fertilization membrane) is used as an indicator of toxic effects on sperm viability and/or the fertilization response. This study, in conjunction with earlier work, has shown that the results of sperm bioassays can be affected by a number of factors including temperature, pH, salinity, sperm:egg ratios, sperm exposure times, test materials, and echinoid species. Each of these factors have been considered in designing the “standard” conditions for the improved test. Examples of the effect of these factors on the test results are illustrated, using silver as a reference toxicant.
143 citations
TL;DR: Larval growth was the best indicator in detecting copper pollution, since it could detect copper at relatively low concentrations, while larval deformities offered a quick tool to evaluate copper pollution.
Abstract: The development and hatchability ofChironomus decorus eggs were not affected by 01 to 5 mg/L of copper in water The embryos developed normally and hatched at about the same time (after 55 hr of incubation) All larvae survived the duration of the test (72 hr) except those subjected to 5 mg/L of copper in water, which died after only partial emergence from the egg shell Apparently, eggs were protected by their shell from copper Growth ofC decorus larvae was reduced significantly when they were reared in copper-spiked food-substrate (bound copper) from the age 1 to 15 days old (900–4,500 mg/kg of copper) The substrate copper concentration at which larval growth was reduced to 50% (EC50) was 1,602 mg/kg Substrate copper caused deformities in the epipharyngeal plate of larval mouthparts and copper concentration higher than 1,800 mg/kg delayed adult emergence The copper concentration in pupal exuviae and adults were positively correlated to copper concentration in the substrate in which they had been reared as larvae Larval stage appeared to be the most sensitive to copper toxicity, while eggs were the least sensitive Larval growth was the best indicator in detecting copper pollution, since it could detect copper at relatively low concentrations The time to adult emergence was not considered a very good indicator, while larval deformities offered a quick tool to evaluate copper pollution
107 citations
TL;DR: In the period 1980 to 1982, nineteen CormorantsPhalacrocorax carbo, three Grey HeronsArdea cinerea and one Great Crested GrebePodiceps crisatus were collected in The Netherlands and their livers were analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans.
Abstract: In the period 1980 to 1982, nineteen CormorantsPhalacrocorax carbo, three Grey HeronsArdea cinerea and one Great Crested GrebePodiceps crisatus were collected in The Netherlands. The livers of these fish-eating birdspecies were analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans. Only congeners with a 2,3,7,8-chlorine substitution pattern were found in the livers. Major components were 2,3,4,7,8-pentachlorodibenzofuran and 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzo-p-dioxin and 1,2,3,7,8-pentachlorodibenzo-p-dioxin were also present. Six pooled samples of the EelAnguilla anguilla, showed the same congeneric pattern of chemicals as found in these bird species. In the Eel, 2,3,4,7,8-pentachlorodibenzofuran and 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin were generally present in the 1 to 5 ng/kg range. Since the Eel is the Cormorant's 2 major food, this indicates strong bioaccumulation for both congeners in the liver of the Cormorant. Significant correlations were found between the various congeners retained in the liver of the Cormorant. It is proposed that this is a result of a continous exposure to a relatively stable background mixture, probably originating from fish consumption. Based on the congeneric patterns found in the Cormorant, polychlorinated biphenyls and pentachlorophenol are suggested as major contaminating sources for this species. Based on the results from the Cormorants, an open one compartment model was applied to estimate concentrations of 2,3,4,7,8-PnCDF in the Eel. These calculations were in good agreement with the actual measurements found in the Eels.
95 citations
TL;DR: In acute tests of toxicity, two cladocerans,Daphnia galeata mendotae andCeriodaphnia lacustris, and the calanoid,Diaptomus oregonensis, were more sensitive to fenvalerate than Daphnia magna, the organism used in standard laboratory bioassays.
Abstract: In acute tests of toxicity, two cladocerans,Daphnia galeata mendotae andCeriodaphnia lacustris, and the calanoid,Diaptomus oregonensis, were more sensitive to fenvalerate thanDaphnia magna, the organism used in standard laboratory bioassays. The 48-hr EC50s for each species/stage in order of increasing sensitivity were adultD. magna — 2.52 μg/L;D. magna (≤48-hr old) — 0.83 μg/L; adultD. galeata mendotae — 0.29 μg/L; adultC. lacustris — 0.21 μg/L;D. galeata mendotae (≤48-hr old) — 0.16 μg/L; adultDiaptomus oregonensis — −0.12 μg/L. No toxicity was observed when these organisms were exposed to a range of concentrations of the emulsifiable concentrate without fenvalerate (the EC blank).
88 citations
TL;DR: This test series developed methods for testing a compliment of aquatic organisms in a single test that satisfies the freshwater acute toxicity requirements for setting water quality criteria and can produce the minimum acute data set for the derivation of a water quality criterion in less time.
Abstract: This test series developed methods for testing a compliment of aquatic organisms in a single test that satisfies the freshwater acute toxicity requirements for setting water quality criteria. Species tested included fathead minnowsPimephales promelas, rainbow troutSalmo gairdneri, bluegillLepomis macrochirus, channel catfishIctalurus punctatus, goldfishCarassius auratus, white suckerCatostomus commersoni, daphnidDaphnia magna, midgeTanytarsus dissimilis, crayfishOrconectes immunis, snailAplexa hypnorum, tadpoleXenopus laevis, and leechNephelopsis obscura. Five to nine of the preceding species were simultaneously exposed in individual tests. The chemicals tested were acrolein, aniline, dibutylfumarate, 2,4-dinitrophenol, Guthion®, nicotine sulfate, phenol, rotenone, silver, Systox®, 1,2,4-trichlorobenzene, 2,4,6-trichlorophenol, ando-xylene. This method of simultaneously exposing aquatic organisms in separate compartments of each exposure tank allows more accurate comparisons of species sensitivity with a tested chemical. Use of this method can also produce the minimum acute data set for the derivation of a water quality criterion in less time and with a substantial cost saving for labor, materials, and chemical analyses when compared with measured concentration tests conducted separately with each individual species.
86 citations
TL;DR: There were no observed treatment effects on the thyroid, pituitary, adrenal glands or serum T4 or T3 levels of adult mink, and there was evidence of significant placental transfer of MeHg to the fetus, and transfer of PCB to growing kits via the mother's milk.
Abstract: Ranch-bred mink (Mustela vison) were maintained in outdoor cages and fed experimental diets containing either polychlorinated biphenyls (Aroclor® 1254) and/or MeHg (methylmercury) for eight months. Unexpected mortality of some mink was attributed to a combination of cold stress and exposure to 1.0 μg/g MeHg. Mortality was lower in the group exposed to a combination of 1.0 μg/g MeHg plus PCB. There were no observed treatment effects on the thyroid, pituitary, adrenal glands or serum T4 or T3 levels of adult mink. There was evidence of significant placental transfer of MeHg to the fetus, and transfer of PCB to growing kits via the mother's milk.
TL;DR: The hepatic concentrations of metals varied between sexes, and with reproductive status of the matured female; the concentration of Fe was lower in the females than the males, and Fe, Pb, Ni, and Co concentrations in the matured females decreased with progress of gestation.
Abstract: The concentrations of heavy metals in the livers of southern minke whales,B. acutorostrata, were determined by atomic absorption spectrophotometry, and their accumulation levels and variations were compared to food habit, and biological parameters. The concentration levels and bioconcentration factors of metals in the minke whale were relatively high for Fe and Cd and low for Hg, when compared to seals and small-toothed cetaceans from different waters. For most of the metals examined, the concentrations were log-normally distributed. The concentrations of Fe, Cd, and Hg were positively correlated with age, but a correlation was not observed for the other metals. While the hepatic Fe concentration linearly increased with age, the concentrations of Cd and Hg increased up to the age of about 20 years and thereafter decreased year by year. Such unusual age trends of Cd and Hg are considered to be due to recent changes of the amount of food intake by the minke whale, as a result of structural disturbances in the Antarctic marine ecosystem due to commercial whaling. Also, the hepatic concentrations of metals varied between sexes, and with reproductive status of the matured female; the concentration of Fe was lower in the females than the males, and Fe, Pb, Ni, and Co concentrations in the matured females decreased with progress of gestation.
TL;DR: A bioenergetics-based pollutant accumulation model was used to describe total mercury accumulation for the commercially valuable Atlantic herring aged 3 to 5 years with the predicted values falling within one standard deviation of the measured annual body burdens.
Abstract: Measured muscle and whole fish total mercury concentrations showed significant positive correlations with age, weight and length, in order of decreasing correlation. Within herring age classes, however, muscle and whole fish mercury concentrations showed significant negative correlations with weight and length due to a ‘growth dilution’ effect in 1- and 2-year-old herring, but demonstrated positive correlations with weight and length in 3- to 5-year-old fish. A bioenergetics-based pollutant accumulation model was used to describe total mercury accumulation for the commercially valuable Atlantic herring aged 3 to 5 years with the predicted values falling within one standard deviation of the measured annual body burdens.
TL;DR: This study suggests that cytogenetic analysis of resident small mammals is a feasible test model for assessment of environmental mutagenesis.
Abstract: Examination of standard metaphase chromosome preparations was employed to evaluate the use of resident small mammals as indicators of environmental mutagenesis. Small mammals of two species, (Peromyscus leucopus andSigmodon hispidus) were trapped over a two-year period at a locality polluted with a complex mixture of petrochemical waste products, heavy metals, and PCBs (polychlorinated biphenyls), and from two uncontaminated localities. Significant differences in levels of chromosomal aberrations between animals collected at the contaminated site and the uncontaminated sites were clearly indicated. Increases in lesions per cell and aberrant cells per individual were shown for both species at the contaminated site compared to the control sites. Levels of chromosomal aberrations were not different between the two control sites, however. This study suggests that cytogenetic analysis of resident small mammals is a feasible test model for assessment of environmental mutagenesis.
TL;DR: The results suggest that growth and survival of mink kits are adversely affected at dietary levels of PCB and MeHg currently present in some environments.
Abstract: Adult ranch-bred mink (Mustela vison) were fed diets containing either 0, 1.0 μg/g polychlorinated biphenyls (PCB) (Aroclor® 1254), 1.0 μg/g methylmercury (MeHg), a combination of 1.0 μg/g PCB plus 1.0 μg/g MeHg, or 0.5 μg/g PCB plus 0.5 μg/g MeHg. Fertility of adult male mink, percentage of females whelped or number of kits born per female were not affected by the treatments. However, growth rate of kits nursed by mothers exposed to 1.0 μg/g PCB was significantly reduced. There was a synergistic effect of PCB and MeHg which reduced kit survival in groups receiving both chemicals simultaneously. Kit survival to weaning in the control, 0.5 μg/g PCB/MeHg, and 1.0 μg/g PCB/MeHg groups was 72.0%, 62.7% and 35.8%, respectively. The results suggest that growth and survival of mink kits are adversely affected at dietary levels of PCB and MeHg currently present in some environments.
TL;DR: It is shown that in the gills zinc competes with cadmium for metal binding sites both within the particulate fraction and the high-molecular weight fraction of the cytosol, and accelerates Cd transport from the gilling towards the internal organs.
Abstract: Freshwater clams (Anodonta cygnea) were exposed to Cd2+ (25 μg/L) or to Cd2+ (25 μg/L) plus Zn2+ (2.5 mg/L). In the presence of zinc, uptake of cadmium in whole clam was halved. In organs such as the gills, mantle, and labial palps a still larger reduction of Cd accumulation occurred. By contrast, accumulation in midgut gland and kidney was hardly affected by the presence of zinc. It is shown that in the gills zinc competes with cadmium for metal binding sites both within the particulate fraction and the high-molecular weight fraction of the cytosol. Zinc probably did not induce an enlarged synthesis of specific metal-binding, metallothionein-like, proteins. In conclusion, zinc exerts antagonistic effects on uptake of cadmium by gills, and accelerates Cd transport from the gills towards the internal organs.
TL;DR: Analysis of Pb, Mn, and Cd in tissue samples showed the expected dose-dependent accumulation when the metal was administered singly, but combined treatment produced different types of metal shift in different tissues, suggesting changes in the metallic distribution within the tissues after coexposure may be the result of a competition between the administered metals for common binding sites.
Abstract: Growing rats were exposed to 5 mg/L Pb,ad libitum in drinking water, and administered low or high doses of Mn and Cd intraperitoneal (ip) for 30 days Some groups of animals were also administered combinations of Pb + Mn and Pb + Cd in an identical manner Analysis of Pb, Mn, and Cd in tissue samples showed the expected dose-dependent accumulation when the metal was administered singly However, combined treatment produced different types of metal shift in different tissues Enhanced accumulation of all three metals in the brain, Mn in liver, Pb in kidney and Cd in testis and kidney after combined exposure may make target organs vulnerable to the toxic effects of metals, even when encountered at low concentrations Further, the decreased levels of blood Pb after combined treatment with Cd or Mn suggests that the significance of blood Pb level as a diagnostic aid for Pb toxicity in coexposed conditions may not be of much value Changes in the metallic distribution within the tissues after coexposure may be the result of a competition between the administered metals for common binding sites
TL;DR: Fourth instar larvae of the midge,Chironomus decorus, were exposed to copper in water and copper in food and substrate (bound forms) and copper present in aqueous forms was more toxic than when it was present in bound forms.
Abstract: Fourth instar larvae of the midge,Chironomus decorus, were exposed to copper in water and copper in food and substrate (bound forms). Copper present in aqueous forms was more toxic than when it was present in bound forms. The relationship between copper in water and copper in midges could be described by an exponential equation while the relationship between copper in substrate and midges was best described by a simple linear regression equation. Midge larvae accumulated copper from water and possessed some mechanisms to regulate copper uptake and excretion when exposed to copper concentrations of 0.05–1.0 mg/L (aqueous forms) and lost that ability when the concentration exceeded 1.0 mg/L. On the contrary, the midge larvae were unable to accumulate copper from food, since the estimated bioconcentration factor was between 0.10 and 0.16. When the midge larvae were exposed to copper in water, the uptake rate increased rapidly from 0–10 hr and then the rate increased very slowly or in some cases it reached a steady state after 10 hr. The steady state was attained within 1 to 3 hr when the midges were exposed to copper in food and substrate.
TL;DR: The production of deformities in the regenerated limbs was the most sensitive response and is consistent with findings in other groups of organisms, in which TBT also produces morphological abnormalities.
Abstract: Treatment of fiddler crabs,Uca pugilator, with levels of tributyltin (TBT) as low as 0.5 μg/L during limb regeneration resulted in a retardation of the regenerative growth and a delay in ecdysis at the end of the regeneration process. Limbs regenerated in the presence of TBT showed a variety of deformities, primarily a curved appearance. This was particularly apparent in regenerated chelae, in which the dactyl curved away from, rather than towards, the pollex. The number of setae was reduced in limbs that regenerated in TBT, compared to those that regenerated in clean sea water. Those that regenerated in clean sea water had a reduced number of setae in comparison to intact limbs. The production of deformities in the regenerated limbs was the most sensitive response and is consistent with findings in other groups of organisms, in which TBT also produces morphological abnormalities.
TL;DR: Grass shrimp are useful as an epibenthic test species for waterborne and sediment-source toxicants and amphioxus is not recommended as a routine test species because of difficulty in distinguishing severely affected from dead individuals.
Abstract: Grass shrimp (Palaemonetes pugio) were exposed to either waterborne or sediment-source concentrations of fenvalerate, cypermethrin, 1,2,4-trichlorobenzene (TCB), tributyltin oxide (TBTO), triphenyltin oxide, and di-n-butylphthalate in static or flow-through test systems. Similarly, amphioxus (Branchiostoma caribaeum) were tested with fenvalerate, TCB, and TBTO. The LC50 and no-effect and 100% mortality concentrations are reported from 96-hr and 10-day tests. The toxicity of contaminated sediments could be explained by chemical partitioning into overlying or interstitial water. Amphioxus is not recommended as a routine test species because of (1) difficulty in distinguishing severely affected from dead individuals, (2) inability to determine the status of burrowed animals without disrupting sediment, (3) their relative lack of sensitivity in acute exposures to toxic chemicals, and (4) difficulty in routine collection of sufficient numbers of animals. Grass shrimp, however, are useful as an epibenthic test species for waterborne and sediment-source toxicants.
TL;DR: In this paper, investigations were conducted into 311 events of suspected contaminations of wells with pesticides between the years 1979 and 1984, which involved the analyses of water from 359 wells where the suspected contamination originated from spills (i) spills (ii) spray drift or (iii) surface runoff waters carrying pesticides into wells.
Abstract: Between the years 1979 and 1984, investigations were conducted into 311 events of suspected contaminations of wells with pesticides. This involved the analyses of water from 359 wells where the suspected contamination originated from (i) spills (ii) spray drift or (iii) surface runoff waters carrying pesticides into wells. Investigations covered 83 spill events involving 104 rural wells; tests revealed 79 of these became contaminated. The contaminations were caused by (i) spills of pesticide concentrates (ii) back-siphoning of spray solutions and/or (iii) spills from overfilling, emptying or rinsing spray equipment. The pesticides either entered directly into the wells or contaminated the area in the vicinity of the wells. In spite of cleanup attempts, difficulty was experienced in decontaminating most well waters and some had to be abandoned. The longest period of monitoring a contaminated well was 1, 117 days; during that time the decline in residue was slow. Investigations were made into 228 events involving 255 wells where spray drift and/or surface runoff waters with pesticides were observed as entering the well; however, only 55 were found to contain detectable residues. The highest proportion of these events was associated with surface runoff or spray drift from cornfields; of 86 wells involved only 26 contained measurable residues and all involved atrazine. Fifty-seven well investigations were associated with spraying right-of-ways and 16 waters were contaminated with 2,4-D and dichlorprop. The remaining 13 well contaminations were associated with various other land-use activities. It required 45 to 347 days to decontaminate these 55 wells.
TL;DR: Aldicarb significantly and repeatedly suppressed the splenic plaque forming cell response to sheep red blood cells at the lowest concentrations tested: the 1 ppb level elicited greater suppression of plaque forming cells and other immune factors than did 1,000 ppb of aldicar.
Abstract: The effects of aldicarb (a carbamate insecticide and nematocide) on selected immune and non-immune parameters of mice were examined. The primary objective was to determine whether exposure to low levels of aldicarb through drinking water could affect selected immune functions. Aldicarb was administered via drinking water either at 10, 100, and 1,000 parts per billion (ppb)2 for 14 days or at 1, 10, 100, and 1,000 ppb for 34 days. The 34-day experiment was repeated twice with minor variations. Aldicarb significantly and repeatedly suppressed the splenic plaque forming cell response to sheep red blood cells at the lowest concentrations tested: the 1 ppb level elicited greater suppression of plaque forming cells and other immune factors than did 1,000 ppb of aldicarb. This inverse dose-response represents a dramatic departure from the classic toxicologic dose-response curve, where toxicity increases with increasing dose levels.
TL;DR: No consistent histopathologic lesions were found in the thyroid or adrenal glands of the 345-HCB-treated mink, nor were there any statistically significant differences in serum epidermal growth factor levels, plasma 17β-estradiol and progesterone concentrations, hepatic aminopyrine N-demethylase, and benzo(α)pyrene hydroxylase activities, hypothalamic norepinephrine, dopamine, and serotonin concentrations.
Abstract: Diets supplemented with 0.01 or 0.05 ppm (mg/kg) of 3,4,5,3′,4′,5′-hexachlorobiphenyl (345-HCB) were fed to mink to investigate the toxicological manifestations of this toxic polychlorinated biphenyl congener in a sensitive species. Dietary exposure of mink to 0.05 ppm 3,4,5,3′,4′,5′-hexachlorobiphenyl for 135 days resulted in 50% mortality while no deaths occurred on 0.01 ppm 345-HCB. Clinical signs of toxicity included anorexia, bloody stools, disrupted molting patterns, and thickened, elongated and deformed nails. Ascites and gastric ulcers were present in animals that died. Statistically significant increases in liver, kidney, and adrenal gland weights were found in the 345-HCB-treated mink. Decreases in total and free triiodothyronine concentrations were observed in mink fed the 345-HCB-treated diets and total thyroxine was decreased in the mink fed 0.05 ppm 345-HCB. No consistent histopathologic lesions were found in the thyroid or adrenal glands of the 345-HCB-treated mink, nor were there any statistically significant differences between the 345-HCB-treated and the control mink in serum epidermal growth factor levels, plasma 17β-estradiol and progesterone concentrations, hepatic aminopyrine N-demethylase, and benzo(α)pyrene hydroxylase activities, hypothalamic norepinephrine, dopamine, and serotonin concentrations or in the incorporation of (3H) thymidine by concanavalin-A-stimulated lymphocytes.
TL;DR: Exposure of sperm of killifish from a relatively clean area in Long Island (LI) to 0.01 mg/L methylmercury (meHg) in 15%o sea water caused significant reduction of fertilization success, but exposure of Killifish sperm from polluted Piles Creek (PC) to either 0.1 or 0.05mg/L meHg prior to insemination had no effect on fertilizationSuccess.
Abstract: Exposure of sperm of killifish (Fundulus heteroclitus) from a relatively clean area in Long Island (LI) to 0.01 mg/L methylmercury (meHg) in 15%o sea water caused significant reduction of fertilization success. However, exposure of killifish sperm from polluted Piles Creek (PC) to either 0.01 or 0.05 mg/L meHg in 15%o sea water prior to insemination had no effect on fertilization success. Exposure of LI killifish sperm to 0.05 mg/L meHg caused significant reduction in motility. However, PC killifish sperm showed no significant difference in motility between 0 and 0.05 mg/L meHg exposure. Exposure for 5 min to 0.05 mg/L meHg caused significant reduction in motility. These data indicate that meHg is less toxic to PC killifish sperm than LI killifish sperm. Exposure of PC and LI killifish sperm to 0.05 mg/L meHg for 15 min had no effect on sperm morphology. PC killifish sperm also showed higher (20 min) motility in 15%o sea water than LI killifish sperm (10 min). Exposure of PC and LI killifish eggs up to 25 min to 0.05 mg/L meHg prior to fertilization had no effect on fertilization success.
TL;DR: Water samples from 11 wells located in an area of intensive vegetable production on an organic soil were collected in 1981 and 1982, and analyzed for pesticide residues as mentioned in this paper, and the highest residue of atrazine (74 μg/L) was present in one well along with contamination of three other herbicides and one insecticide.
Abstract: Water samples from 11 wells located in an area of intensive vegetable production on an organic soil were collected in 1981 and 1982, and analyzed for pesticide residues. Residues of diazinon, malathion, allidochlor, linuron, and prometryne were identified in four of the wells. Water samples from 91 wells were collected from farms on mineral soils across Southern Ontario during 1984 and analyzed for pesticide residues. Atrazine residues (0.1 to 74 μg/L) were present in 11 wells and trifluralin residues (41μg/L) contaminated one well. The highest residue of atrazine (74 μg/L) was present in one well along with contamination of three other herbicides and one insecticide. This was the result of a spill into the drilled well that gave residues of each component between 22 and 125μg/L. After 10 months of cleaning, this well was still contaminated.
TL;DR: Fathead minnows, 30 days old, and Rainbow trout (Salmo gairdneri) injected with radiolabeled bromacil or diuron eliminated over 90% of the radioactivity within 24 hr, and parent compound and metabolites were detected in the aquarium water in both cases.
Abstract: Fathead minnows, 30 days old, were exposed to technical grade bromacil and diuron in flow-through tests to determine acute toxicity. LC50 values for bromacil were 185, 183, 182 and 167 mg/L at 24, 48, 96, and 168 hr, respectively; and for diuron, 23.3, 19.9, 14.2, and 7.7 mg/L at 24, 48, 96, and 192 hr, respectively. Eggs, newly hatched fry, and juvenile fish were continuously exposed to lower concentrations of the herbicides for 64 days. Growth was significantly reduced (p ⩽ 0.01) at the lowest bromacil exposure of 1.0 mg/L. Therefore, it was not possible to determine a “no effect” concentration. The “no effect” concentration for diuron was 33.4 μg/L, while the lowest concentration which resulted in adverse effects was 78.0 μg/L. Adverse effects at 78.0 μg/L were an increased incidence of abnormal or dead fry immediately after hatch (p ⩽ 0.01) and decreased survival throughout the exposure period (p ⩽ 0.05). Neither herbicide accumulated significantly in fish tissue, as bioconcentration factors were <3.2 and 2.0 for bromacil and diuron, respectively. Rainbow trout (Salmo gairdneri) injected with radiolabeled bromacil or diuron eliminated over 90% of the radioactivity within 24 hr. Parent compound and metabolites were detected in the aquarium water in both cases. Metabolites of diuron recovered from the water included 3,4-dichloroaniline and several demethylated products.
TL;DR: An increase in chlorinated hydrocarbons with increase in body size and fat content is revealed in fish species from Abu Qir Bay and Tilapia species from Idku and Maryut lakes.
Abstract: Residues of polychlorinated biphenyls (PCBs) and organochlorine chemicals were analyzed by capillary gas chromatography in five fish species from Abu Qir Bay as well as in Tilapia species from Idku and Maryut lakes in Alexandria, Egypt. σDDT and PCBs were the most predominant contaminants occurring in the muscle tissue of all fish samples. Remarkable variations in the concentrations of PCBs were noted among the species, and the concentrations of σDDT were higher than that of PCBs in all fish species. Elevated PCB concentrations were observed in muscle tissue ofSargus vulgarius from Abu Qir Bay, and inTilapia zillii from Forn El-Gieraia, Maryut lake. Also, variations were found in the relative proportions ofp,p′-DDT,p,p′-DDD, andp,p′-DDE in all fish samples. The results revealed an increase in chlorinated hydrocarbons with increase in body size and fat content. Neither α-endosulfan nor β-endosulfan was detected in fish from Abu Qir Bay; however, only α-endosulfan was detected in trace amounts in Tilapia species from Idku and Maryut lakes. With the exception ofSargus vulgarius, mirex and methoxychlor occurred in low levels in all other fish species. Potential health hazards are discussed with the tolerance levels recommended.
TL;DR: Of the elements studied, only Pb regularly exceeded current guidelines for elemental contaminants in foods and was highly correlated with Ca content, which was probably determined largely by the amount of tissue other than muscle in the sample because fish muscle contains relatively little Ca.
Abstract: The influence of sample preparation on measured concentrations of eight elements in the edible tissues of two black basses (Centrarchidae), two catfishes (Ictaluridae), and the black redhorse,Moxostoma duquesnei (Catostomidae) from two rivers in southeastern Missouri contaminated by mining and related activities was investigated. Concentrations of Pb, Cd, Cu, Zn, Fe, Mn, Ba, and Ca were measured in two skinless, boneless samples of axial muscle from individual fish prepared in a clean room. One sample (normally-processed) was removed from each fish with a knife in a manner typically used by investigators to process fish for elemental analysis and presumedly representative of methods employed by anglers when preparing fish for home consumption. A second sample (clean-processed) was then prepared from each normally-processed sample by cutting away all surface material with acid-cleaned instruments under ultraclean conditions. The samples were analyzed as a single group by atomic absorption spectrophotometry. Of the elements studied, only Pb regularly exceeded current guidelines for elemental contaminants in foods. Concentrations were high in black redhorse from contaminated sites, regardless of preparation method; for the other fishes, whether or not Pb guidelines were exceeded depended on preparation technique. Except for Mn and Ca, concentrations of all elements measured were significantly lower in cleanthan in normally-processed tissue samples. Absolute differences in measured concentrations between clean- and normally-processed samples were most evident for Pb and Ba in bass and catfish and for Cd and Zn in redhorse. Regardless of preparation method, concentrations of Pb, Ca, Mn, and Ba in individual fish were closely correlated; samples that were high or low in one of these four elements were correspondingly high or low in the other three. In contrast, correlations between Zn, Fe, and Cd occurred only in normallyprocessed samples, suggesting that these correlations resulted from high concentrations on the surfaces of some samples. Concentrations of Pb and Ba in edible tissues of fish from contaminated sites were highly correlated with Ca content, which was probably determined largely by the amount of tissue other than muscle in the sample because fish muscle contains relatively little Ca. Accordingly, variation within a group of similar samples can be reduced by normalizing Pb and Ba concentrations to a standard Ca concentration. When sample size (N) is large, this can be accomplished statistically by analysis of covariance; whenN is small, molar ratios of [Pb]/[Ca] and [Ba]/[Ca] can be computed. Without such adjustments, unrealistically large Ns are required to yield statistically reliable estimates of Pb concentrations in edible tissues. Investigators should acknowledge that reported concentrations of certain elements are only estimates, and that regardless of the care exercised during the collection, preparation, and analysis of samples, results should be interpreted with the awareness that contamination from external sources may have occurred.
TL;DR: The toxicities of several chlorinated benzene compounds to fathead minnows (Pimephales promelas) were determined and juvenileFathead minnow behavior was affected and lipid content was reduced when compared to the control.
Abstract: The toxicities of several chlorinated benzene compounds to fathead minnows (Pimephales promelas) were determined. Chronic toxicities were estimated from 32–33 day embryo through early juvenile development exposures. The ranges between the highest no observable effect concentration (NOEC) and lowest observed effect concentration (LOEC) were 1,000–2,300, 570–1,000, and 240–410 μg/L for 1,3-dichlorobenzene (1,3-DCB), 1,4-dichlorobenzene (1,4-DCB), and 1,2,3,4-tetrachlorobenzene (1,2,3,4-TCB), respectively. Pentachlorobenzene (Penta-CB) and hexachlorobenzene (HCB) were non-toxic at the highest concentrations of 55 and 4.8 μg/L (near water saturation), respectively, that could be maintained in the test chambers. The tissue concentrations associated with the NOEC and LOEC for 1,3-DCB, 1,4-DCB and 1,2,3,4,-TCB were 120–160, 70–100, and 640–1,100 μg of chemical per gram of fish tissue (wet weight), respectively. The mean Penta-CB and HCB tissue concentration obtained at the NOEC of 55 and 4.8 μg/L were 390 and 97 μg/g, respectively. Mean bioconcentration factors obtained in these tests were 97, 110, 2,400, 8,400 and 22,000 for 1,3-DCB, 1,4-DCB, 1,2,3,4-TCB, Penta-CB and HCB, respectively. At a Penta-CB concentration of 130 μg/L (near water saturation) in a six day exposure conducted in the reservoir of the chemical saturating apparatus and control, juvenile fathead minnow behavior was affected and lipid content was reduced when compared to the control. Ninety-six hr LC50 values, obtained with juvenile fish, for 1,3-DCB, 1,4-DCB, and 1,2,3,4-TCB were 7,800, 4,200, and 1,100 (μg/L, respectively.
TL;DR: Occurrence of DDT and its metabolites in resident wildlife and its food indicates continuing contamination that probably originates largely from past legal applications in the orchard system.
Abstract: Residues of the DDT group, particularlyp,p′-DDT (DDT) were detected in high or unusual amounts in some wildlife samples collected in fruit orchards near Wenatchee, Washington from 1979 to 1983. Samples of birds containedp,p′-DDE (DDE) and DDT in ratios (DDE:DDT) as low as 2.6:1 in eggs and 1.9:1 in brains. An unexpectedly high number (about 50%) of some samples, such as fat of adult waterfowl, contained unusually low DDE:DDT ratios (≤10:l). At the lower sensitivity level (0.01 μg/g), 96% of the samples contained DDE and 46% contained DDT. From about 1946 to 1970, technical DDT was applied at very high rates to orchards in Washington (56 to 73 kg/ha/yr); some areas probably received 5≥1000 kg/ha over this period. Considerable wildlife mortality from DDT was documented during the period of intensive use, but only one DDT-related mortality was recorded during this study. The possible origin of the residues is discussed. Occurrence of DDT and its metabolites in resident wildlife and its food indicates continuing contamination that probably originates largely from past legal applications in the orchard system.