Showing papers in "Archives of Environmental Contamination and Toxicology in 1983"

The acute oral toxicity, repellency, and hazard potential of 998 chemicals to one or more species of wild and domestic birds.

Abstract: The acute oral toxicity, repellency, and hazard potential of 998 chemicals to one or more of 68 species of wild and domestic birds was determined by standardized testing procedures. Red winged blackbirds were the most sensitive of the bird species tested on a large number of chemicals, and an index based on redwing toxicity and repellency may provide an appropriate indication of the probability of acute avian poisoning episodes. Avian repellency and toxicity were not positively correlated (i.e. toxicity varied independently with repellency).

The Photochemical Generation of Hydrogen Peroxide in Natural Waters

Abstract: The photochemical formation of hydrogen peroxide in tryptophan solutions and natural waters was monitored by a sensitive spectrophotometric assay. Peroxide was characterized by ion exchange properties and mobility via thin-layer chromatography. Tryptophan photodecomposed in sunlight or near ultraviolet light (λ > 283 nm) with the formation of uncharacterized, acidic photoproducts and hydrogen peroxide; other oxidants (i.e. organic peroxides) were not detected in tryptophan photolysis mixtures. After brief exposure to sunlight, hydrogen peroxide in natural waters varied from below the detection limit (1.5μM) to 6.8μM; in highly eutrophic samples peroxide was formed in excess of 30μM. A humic acid soil extract, tyrosine, and several aromatic compounds including substituted phenols and anilines also generated stable photochemical oxidants suggesting that many compounds may serve as sources for hydrogen peroxide in natural waters.

Synthetic musk residues in biota and water from Tama River and Tokyo Bay (Japan).

Abstract: Musk xylene and musk ketone (synthetic musks) were detected in 100% and 80%, respectively of 74 samples, [freshwater fish (three species), marine shellfish (four species), river water, and wastewater (three sewage treatment plants)] collected from several sampling stations along the Tama River, a dam, and Tokyo Bay, during July and October, 1980 and 1981. The average concentrations of musk xylene were 53.9 ppb in the viscera of freshwater fish, 16.0 ppb in the fish muscle, and 2.7 ppb in marine shellfish; the mean levels of musk ketone were 30.5 ppb in the viscera, 7.8 ppb in the muscle, and 1.6 ppb in the shellfish. The mean levels in river water were 4.1 ppt for musk xylene and 9.9 ppt for musk ketone, but no detectable levels of musk ketone were found in freshwater fish and river water upstream of the Tama River and the dam. The highest concentrations of both compounds were observed in freshwater fish down-stream, and that in water samples were found in wastewater from the sewage treatment plants, situated along the banks of the river. The results suggested that both compounds exist as bioaccumulation-type pollutants in the aquatic ecosystem.

Role of participate organic matter in decreasing accumulation of polynuclear aromatic hydrocarbons byDaphnia magna

Abstract: Accumulation of benzo[a]pyrene (BaP) and anthracene (A) byDaphnia magna in the presence of suspended yeast cells was analyzed using multicompartment models. The rate coefficient for uptake of polynuclear aromatic hydrocarbon (PAH) due to ingestion of yeast cells laden with sorbed chemical was only 3 to 15% of the rate coefficient for uptake of dissolved PAH. Uptake and accumulation of BaP was reduced 97% due to sorption of PAH to naturally occurring organic matter (humic acids). Accumulation of hydrophobic chemicals in aqueous systems appears to depend on the amount of chemical in solution and on the amount of chemical sorbed to particles entering the food chain. Chemicals sorbed to suspended organic matter, including dissolved or colloidal organic matter, have greatly reduced availability.

Distribution of cadmium and zinc in tissues and organs, and their age-related changes in striped dolphins, Stenella coeruleoalba.

Abstract: Cadmium and zinc concentrations were determined in the tissues and organs, including the fetus, of striped dolphins. The kidney showed the highest cadmium concentration and the hepatic cadmium concentration was also relatively high. A similar distribution pattern among soft tissues was also observed with zinc, where its concentration varied less than that of cadmium. A significant positive correlation between zinc and cadmium was found in both the kidney and the liver; the increase of zinc concentration with cadmium was more marked in the liver (Zn:Cd 3∶1 on molar basis) than kidney (Zn:Cd 1∶1). Negligible cadmium concentration in the fetus suggested that cadmium is not transferred to the fetus via the placenta from the mother. Organ-specific age trends of cadmium and zinc concentrations were presented in detail for muscle, liver, kidney, pancreas, brain, and blood. Both metals showed rapid change during the periods of the fetus and weaning.

Ecological significance of behavioral and hormonal abnormalities in breeding ring doves fed an organochlorine chemical mixture.

Abstract: Ring Doves (Streptopelia risoria) with breeding experience were fed a control diet or one of two dosages of a mixture of DDE, PCBs, mirex, and photomirex throughout an isolation period of 90 days and one reproductive cycle. Daily observations were made of courtship and parental behaviors. Circulating levels of androgens, estrogens, progesterone, thyroxine, and prolactin were measured in the appropriate sex at selected points in the breeding cycle. The organochlorine mixture altered the nature and duration of courtship behavior in a dose-related fashion resulting in marked asynchrony in the breeding cycle. Alterations were apparently mediated through the female. Incubation and brooding behavior was altered in a dose-related fashion and the median incubation period of the high dosage group was extended by three days. Pairs receiving the high dosage spent less time feeding their young. Androgen levels of males, and the estrogen and progesterone levels of females were altered in a dose-related fashion. Thyroxine levels were increased in both sexes in a dose-related fashion and there was an alteration of prolactin levels. Correlations were obtained between behavior and some hormones. There was a marked dose-related decrease in fledging success, resulting in reductions of 15 and 50% in the number of squabs fledged per nesting attempt. Squabs of pairs receiving the high dosage were of lower weight. The results suggest that behavioral anomalies in breeding synchrony, nest construction, incubation attentiveness and parental care induced in a wild bird population by a mixture of organochlorine pollutants could alter reproductive success, increase the energetic cost to the population, and alter the reproductive fitness of contaminated individuals. These effects were seen in Herring Gulls (Larus argentatus) nesting in colonies in Lake Ontario which was highly contaminated by this same suite of organochlorine pollutants in the mid-1970's.

Application of the “ecological dose” concept to the impact of heavy metals on some microbe-mediated ecologic processes in soil

Abstract: It is suggested that the inhibition of microbe-mediated ecologic processes by pollutants be used to quantitate the sensitivity of natural ecosystems to such toxicants. Such a quantification, expressed as an “ecological dose 50%” (EcD501; other percentages of inhibition could also be used), could be easily incorporated into the methodologies used to set the Water Quality Criteria and the national secondary ambient air quality standards and to establish criteria for terrestrial ecosystems. Furthermore, it would be useful in obtaining the “recommended” ecotoxicologic data required from manufacturers of new chemicals by the Toxic Substances Control Act. The applicability of the EcD50 concept was evaluated by studying the effects of cadmium and zinc on the mineralization of carbon in soil and by adapting published data of other investigators on the effects of different heavy metals on some microbe-mediated ecologic processes (i.e., respiration and nitrification) in soils that differ in physicochemical characteristics.

Cytotoxic, mutagenic, and cell-cell communication inhibitory properties of DDT, lindane, and chlordane on Chinese hamster cells in vitro.

Abstract: The cytotoxicity, mutagenicity, andin vitro inhibition of metabolic cooperation of DDT, lindane, and chlordane were studied with Chinese hamster V79 cells. The results showed differential cytotoxicity of these three pesticides (lindane < DDT < chlordane). There was no detectable mutagenic activity of any of these pesticides, using two genetic markers (6-thioguanine and diphtheria toxin resistance). DDT and lindane, however, were shown to have properties similar to 12-O-tetradecanoylphobol-13-acetate (a powerful mouse skin tumor promoter). Above what appeared to be a threshold level, there was a clear dose response of DDT and lindane in thein vitro cell-cell communication assay. Chlordane, which was the most cytotoxic pesticide tested, did not inhibit metabolic cooperation as significantly as did DDT or lindane. The role of these pesticides in carcinogenesis was speculated as being their tumor promoting properties, either at non-cytotoxic levels by mimicing TPA-like membrane alterations or at cytotoxic levels by mimicing partial hepatectomy.

Sources of variability in accumulation of heavy metals by fishes in a roadside stream.

Abstract: Interspecific variations in lead, nickel, cadmium, and zinc concentrations among six species of fish from a highway-contaminated stream were investigated as functions of differences in habitat (sediment contact) and morphology (percentage axial muscle). Association with stream sediment appeared to influence whole-body metals accumulation but percentage muscle did not. Intraspecific variation in whole-body metal concentrations was not positively related to length (as an index of duration of exposure) in any species. However, lead and nickel content of bone and cadmium content of kidney increased consistently between ages 2 and 5 in white sucker, the only species subjected to tissue analysis across age groups. These findings suggest that biological monitoring to assess chronic heavy metal pollution should focus on long-lived benthic species and be directed at tissues with demonstrated affinities for particular metals.

In vivo andIn vitro studies on synergism with anticholinesterase pesticides in the snailLymnaea acuminata

Abstract: The synergistic effects of piperonyl butoxide (PB)2, sulfoxide (SU), and dimethyl amino aniline (DAA) used in conjunction with two organophosphate pesticides (phorate and formothion) and two carbamate pesticides (mexacarbate and carbaryl) were examined in terms of the LC50 and acetylcholinesterase (AChE) inhibition in the snailLymnaea acuminata. The three synergists reduced the LC50 of phorate, formothion, mexacarbate, and carbaryl at exposure periods ranging from 24 to 144 hr. PB and SU had strong synergistic action; DAA had little effect; the highest synergistic ratio (70) was found with carbaryl and PB. The synergists enhanced thein vitro inhibition of cholinesterase caused by the pesticides; the synergistic effect onin vitro inhibition, however, was lower, compared to the change in the LC50.

Polychlorinated biphenyls in harbor porpoises Phocoena phocoena (L.) from the Bay of Fundy, Canada and adjacent waters, with some information on chlordane and hexachlorobenzene levels.

Abstract: Polychlorinated biphenyl (PCBs) levels were measured in tissues from harbor porpoises collected during 1971–77 from the Bay of Fundy (Canada) and adjacent waters. Levels of chlordanes and hexachlorobenzene (HCB) were measured in smaller numbers of the same series of specimens from 1975–77. PCB levels were relatively high in all tissues of sexually immature specimens of both sexes as well as adult males, and relatively low in adult females. The maximum level in blubber was 310 ppm; in other tissues, commensurate with their lower fat content, maxima were rarely more than 2 ppm. PCB levels in blubber, liver, and kidney were correlated with one another. No discernible changes in mean levels between 1971–77 were detected, nor were significant regional differences recognized within the Bay of Fundy, or among specimens obtained between Newfoundland and Rhode Island. Levels increased significantly with age in all tissues from males, and decreased significantly in most tissues from females; individual variation was large. Particularly high levels in four-year old males and three-year old females were related to a growth spurt at puberty with correspondingly elevated food (and hence PCB) intake per unit of time. Chlordanes were present in most tissues, with a maximum of 14 ppm in blubber. Only small quantities (0.12 to 0.43 ppm) of HCB were recorded; the maximum was only 0.43 ppm in blubber, but levels of HCB were strongly correlated with respective PCB levels in the same tissues.

Breeding success of barn owls (Tyto alba) fed low levels of DDE and dieldrin

Abstract: The relative importance of two organochlorine pesticides in the recent reproductive failure of raptors was investigated. Captive barn owls were fed 3.0 ppm DDE and 0.5 ppm dieldrin; doses were given separately and in combination for two years. Breeding success was followed from the laying of eggs through natural incubation and rearing of young. DDE was associated with significant eggshell thinning, egg breakage, embryo mortality, and reduced production per pair. Dieldrin alone was associated with slight but significant eggshell thinning, but not with reduction of breeding success. Ecological implications of the results are discussed; it is suggested that DDE had a much more severe effect on reproduction in wild raptors than dieldrin, which contributed to their decline primarily through adult mortality.

Combined effect of body size, season, and location on trace element levels in mussels (Mytilus edulis).

Abstract: Specimens ofMytilus edulis (mussels) were collected at one-month intervals over a one-year period from two locations in Burrard Inlet, British Columbia, Canada and less frequently from other locations in the S.W. region of B.C., and analyzed for concentrations of Mn, Fe, Cu, Zn, Br, Pb, and Sr using X-ray energy spectroscopy. Size and condition of the mussels were recorded at the same time. The data were analyzed using multiple linear regression with size and season as predictor variables and trace metal contents as criterion variables. The values of the regression coefficients changed according to whether or not the mussels were collected from a polluted environment in disagreement with previously published studies. Principal component analysis of the correlation matrix of the variables yielded three principal components one of which can be used to ascertain whether or not mussels were collected from either a polluted or an unpolluted environment.

Acute and chronic effects of carbaryl on survival, growth, and metamorphosis in the bullfrog (Rana tigrina)

Abstract: The effects of carbaryl (1-naphthalenyl methylcarbamate), an extensively used insecticide in agricultural operations, have been studied on survival, growth, and metamorphosis of the bullfrog tadpoleRana tigrina. The 96 hr LC50 value for tadpoles (0.02 g) was 6.2 mg/L. The tadpoles were reared from hatching to metamorphosis in sublethal concentrations of carbaryl. Rates of feeding, defecation, and excretion increased with increasing concentration of carbaryl but the conversion rate decreased leading to the production of small froglets. The tadpoles exposed to the sublethal concentrations suffered no mortality until the appearance of the forelimb; however, during metamorphosis mortality was significant, even at 2 mg/L.

DDTs and PCB isomers and congeners in antarctic fish

Abstract: Polychlorinated biphenyls (PCBs) and DDTs (p,p′-DDE +p,p′-DDT) were quantitated in four species of antarctic fish collected around the Japanese Antarctic Research Station during January to December 1981. PCBs ranged between 0.08 and 0.77 ng/g and DDTs from 0.3 to 1.9 ng/g, wet weight basis in whole body homogenates. InPagothenia borchgrevinki, the largest sample (N=21), both classes of chlorinated hydrocarbons increased linearly with body weight. Analysis of PCB isomers and congeners by mass fragmentography showed greater retention of the more highly chlorinated biphenyls in larger specimens. The bottom dwellingTrematomus bernacchii andT. hansoni revealed greater concentrations of highly chlorinated biphenyls than the surface dwellingP. borchgrevinki. In general, the concentrations of PCBs and DDTs in antarctic fish were very low compared to other open ocean water fish reported in the literature; this agreed with atmospheric and hydrospheric concentrations of PCBs and DDTs in antarctic regions where low levels were reported.

Concentrations of lead, cadmium, mercury, and copper in the crayfish (Pacifasticus leniusculus) obtained from a lake receiving urban runoff.

Abstract: Commercially caught crayfish (Pacifasticus leniusculus) were placed in a municipal lake below a combined sewer overflow outfall and a storm drain outfall associated with elevated sediment metal concentrations. Abdominal muscle, viscera, and exoskeleton from each crayfish were analyzed for mercury, cadmium, lead, and copper. Crayfish metal concentrations for each sampling site were evaluated relative to unexposed samples from the commercial catch and samples held in the laboratory. Results indicated that 1) mercury accumulated in muscle tissue, highest cadmium concentrations were in the viscera, and highest lead concentrations were in the exoskeleton, 2) uptake of copper is well-regulated by the organism at non-toxic water concentrations, and 3) viscera concentrations of cadmium, lead, and copper tended to be higher and more variable than in muscle tissue. A significant correlation was found between body weight and muscle mercury concentration. Relative to allowable limits for metals in foods, there was not sufficient accumulation of any metal to indicate that a significant health hazard would result from consumption of these organisms. These data indicate that analysis of trace metals in various body parts ofP. leniusculus may be a useful biological indicator of trace metal pollution of freshwater lakes and streams.

Residues of organochlorine insecticides, industrial chemicals, and mercury in eggs and in tissues taken from healthy and emaciated common loons, Ontario, Canada, 1968-1980.

Abstract: Between 1968 and 1980, 98 eggs were collected from active nests of the common loon (Gavia immer) in Ontario. Residues of ⌆DDT and PCB declined over this period while dieldrin and Hg appeared unchanged. Eggs collected in 1969 and 1970 had significantly thinner shells than eggs from a collection made before 1947. Between 1969 and 1979, 215 common loon carcasses were collected across Ontario, the result of having been drowned or shot or having died of diseases or unknown causes. Chemical analyses of 174 carcasses taken from healthy birds showed that adult loons accumulated higher levels of organochlorine and Hg residues than did juveniles. Tissues with high fat contents contained higher organochlorine levels while kidney, liver, and feathers had the highest Hg levels. Thirty loons were found to be emaciated with visibly lesser amounts of body fat and significantly lower levels of lipids in pectoral muscle tissue. Organochlorine but not Hg residues were one to two orders of magnitude higher in the wet tissues of emaciated birds than healthy birds. Higher residues of organochlorine chemicals were found in the uropygial gland, the oil secreted by this gland and belly and back feathers of emaciated birds when compared to healthy birds. It was concluded that losses of organochlorine chemical residues could occur through this gland. While Hg levels in feathers were elevated, Hg did not accumulate in the uropygial gland or in the secreted oil and was not the route for Hg content in feathers. In emaciated birds, mean brain levels of ⌆DDT (primarily DDE) were between 25 and 49 Μg/g, dieldrin 0.5 to 1.2 Μg/g, PCB 39 to 63 Μg/g, and mercury 1.0 to 1.8 Μg/g. The mean brain levels in healthy birds were between 0.2 and 0.9 Μg/g ⌆DDT, 0.01 and 0.05 Μg/g dieldrin, 0.6 and 2.0 Μg/g PCB, and 0.4 and 0.6 Μg/g mercury.

Uptake of lead from aquatic sediment by submersed macrophytes and crayfish.

Abstract: Uptake of lead (Pb) by submersed aquatic macrophytes and crayfish exposed to artificially contaminated pond sediment was measured under laboratory conditions. Macrophytes accumulated Pb in root tissue and foliage. Internal transport of Pb by plants was not detected. Senescent macrophytes accumulated more lead than live plants. Crayfish exposed to contaminated sediment accumulated Pb principally through adsorption to the exoskeleton and lost Pb through molting, although internal uptake and elimination without molting was measurable. Exposure to Pb leached from sediment, surface to weight ratios, and frequency of molting seem to influence Pb uptake by crayfish.

Selenite toxicity and mercury-selenium interactions in juvenile fish.

Abstract: Acute lethal toxicities of selenium and the effects of selenium on mercury accumulation were determined in freshwater fish species. Selenite concentrations required to produce 50% mortality were approximately 11 mg Se/L in northern pike (Esox lucius), 29 mg Se/L in white sucker (Catostomus commersoni), and 5 mg Se/L in yellow perch (Perca flavescens) after 75, 96, and 240 hr of exposure, respectively. Two approaches were used to determine effects of water-borne selenium on mercury concentrations in northern pike. In the first, a trend of reduced mercury contamination at a low selenium concentration (1 ug Se/L) with maintenance at control mercury contamination levels at a higher selenium concentration (100μg Se/L) was apparent. In the second, a similar response of decreased CH3 203Hg accumulation in muscle-skin at lower selenium concentrations (1 and 10μg Se/L), but maintenance at control accumulation levels at a higher selenium concentration (100μg Se/L) was observed. Results and knowledge requirements are discussed with emphasis on relevance to increasing deposition rates of these chemical elements to freshwater ecosystems and using selenium to treat mercury-contaminated aquatic systems.

Developmental and cytogenetic abnormalities induced in the purple sea urchin by environmental levels of benzo(a)pyrene.

Abstract: The teratogenic effects of environmental levels of the mutagen, benzo(a)pyrene (BaP), were investigated using the purple sea urchin (Strongylocentrotus purpuratus) and were related to embryonic cytotoxicity and genotoxicity as evidenced by the presence of aberrant chromosome arrangements during mitosis. Developmental abnormalities were observed in gastrulae treated with initial BaP concentrations of 1 to 50 ng/ml relative to solvent (ethanol)-treated control embryos. However, genotoxic effects were significant at the lowest BaP dose tested, 0.5 ng/ml. When compared to seawater and ethanol control embryos, fewer mitotic figures and increased frequencies of abnormal mitoses were present in BaP-treated gastrulae. Micronucleus formation, a widely used test of genotoxicity in mammals, was observed in embryos exposed to 1 to 50 ng/ml BaP. Grossly abnormal test embryos had high incidences of mitotic aberrations and were composed of large numbers of pycnotic, karyolytic, and multinucleated cells. The results from this cytogenetic analysis demonstrate that mitotic inhibition and aberrations are more sensitive indicators of BaP-induced damage than are developmental effects and suggest that cytogenetic analysis be included in the standard 48-hr sea urchin bioassay procedure when testing contaminants suspected of being mutagens. Cytologic-cytogenetic analysis is particularly suited for use with invertebrates and appears to be as sensitive as more laborious and expensive routine cytogenetic methods which involve karyotyping such as the sister chromatid exchange test.

Worker exposure to paraquat and diquat.

Abstract: Exposure of workers applying paraquat to fields of tomatoes and citrus, and diquat to waterways containing water hyacinths and hydrilla, was monitored with dermal α-cellulose pads attached at each of ten body locations and with personal air monitors. Estimated total body exposure for tomato applicators was apparently influenced by tractor type. Exposure levels from highest to lowest were: open tractor > enclosed cab tractor ⩾ high-clearance tractor. Citrus applicators' exposure to paraquat averaged 28.5 mg/hr and 12.2 mg/hr, with tank concentrations of 0.11% and 0.07%, respectively. Diquat applicators received minimal exposure. Respiratory exposure was <0.1% of the total body exposure in all experiments. Urine samples collected periodically for all workers were, with one exception, without detectable pesticide contamination. Use of disposable coveralls and regularly washed impermeable gloves should effectively reduce exposure.

Some aspects of the determination of organochlorine contaminants in human milk

Abstract: The concentrations of organochlorine pesticides and polychlorinated biphenyls (PCBs) in successive milk fractions collected from two mothers during the course of a feeding were constant for each of the mothers when calculated on a milk fat basis. The levels in milk from one mother collected on six nursing occasions during a 24-hr period were also constant when calculated on the basis of milk fat. When milk collected from three mothers at weekly intervals during several months was analyzed, the levels ofp,p′-DDT,p,p′-DDE and PCBs calculated on a milk fat basis fluctuated slightly in each case; a slight decrease in the concentrations ofp,p′-DDE and PCBs was observed with time.

The acute and chronic toxicity of acetone, dimethyl formamide, and triethylene glycol toDaphnia magna (Straus)

Abstract: Acute and chronic toxicity tests were performed withDaphnia magna (Straus) and three organic solvents commonly used to facilitate the solubilization of lipophilic compounds during acute toxicity tests. The 48-hr LC50 values were: acetone 39000μl/L; dimethyl formamide, 13000μl/L; triethylene glycol, 35000μl/L. Maximum acceptable toxicant concentrations determined during the chronic toxicity tests with acetone, dimethyl formamide, and triethylene glycol were between 1400 and 2800μl/L, 1200 and 2500μl/L, and 5500 and 11000μl/L, respectively. Triethylene glycol was the least toxic solvent and is recommended as the primary choice when selecting a carrier solvent. All three solvents were sufficiently low in toxicity to suggest that the recommended usage limits (500μl/L during acute toxicity tests, 100μl/L during long-term toxicity tests) are adequate for the prevention of solvent related toxicity toD. magna.

Effects of cadmium on yolk utilization, growth, and survival of Atlantic salmon alevins and newly feeding fry.

Abstract: Growth and the yolk-to-embryo gross conversion efficiencies were determined for Atlantic salmon (Salmo salar L.) alevins and fry reared under control conditions and at 0.2 and 2.0 ppb cadmium (Cd). Alevins reared at 2.0 ppb Cd grew more slowly than controls and alevins reared at 0.2 ppb. The size reduction was due primarily to reduction in yolk-conversion efficiency during the latter half of yolk absorption. The rate of yolk uptake was also reduced at 2.0 ppb Cd. Mortality of feeding fry reared up to one month at 2.0 ppb Cd was 80 to 90%. Fry previously reared in 2.0 ppb Cd as alevins experienced lower mortality than those introduced to Cd at start of feeding. Mortality was preceded by hyperactivity and convulsions; 30 to 60% of fry exposed to 2.0 ppb Cd developed cranial swellings. Growth of fry surviving 2.0 ppb Cd for one month was severely retarded. There were no adverse effects from 0.2 ppb Cd.

Methylmercury effects on regeneration and ecdysis in fiddler crabs (Uca pugilator, U. pugnax) after short-term and chronic pre-exposure

Abstract: Methylmercury (meHg) inhibits limb regeneration and molting in fiddler crabs. The present study shows that, inUca pugilator from a clean site, the inhibitory effects of 0.5 Μg/ml meHg were unaffected by short term pre-exposure to low levels (0.06 or 0.1 Μg/ml) of meHg under laboratory conditions. Chronic exposure tests onUca pugnax showed that the inhibitory effects of meHg varied with the sex of the crabs and the level of contamination at the site of collection. These effects were less pronounced in crabs from an area subjected to heavy metal pollution (Piles Creek, Linden, NJ) than in crabs from a relatively cleaner area (Big Sheeps-head Creek, Tuckerton, NJ). The order of susceptibility to meHg according to its interaction with sex and site from least susceptible to most was: Piles Creek females, Piles Creek males, Tuckerton males, Tuckerton females. Residue analysis showed that all groups absorbed equivalent amounts of mercury, but only the females from Piles Creek were able to depurate to near control levels after two weeks in clean water.

Toxicity, bioconcentration, and metabolism of the herbicide propanil (3',4'-dichloropropionanilide) in freshwater fish.

Abstract: Fathead minnows (Pimephales promelas) were exposed to technical grade propanil (3′,4′-dichloropropionanilide) in a flow-through diluter system to determine acute lethality. LC50 values were 11.5, 10.2, 8.6, and 3.4 mg·L−1 at 24, 48, 96, and 192 hr, respectively. Eggs, newly hatched fry, and juvenile fish of this species were similarly exposed but at lower concentrations and for a period of 58 days. The 58-day “no effect” concentration was between 0.4 and 0.6Μg·L−1, based upon the physiological parameters of length and dry weight of juvenile fish.14C-Propanil did not bioconcentrate significantly in fathead minnows (1.6× for parent propanil in whole body). Rainbow trout (Salmo gairdneri) readily metabolized propanil, forming at least ten products. One metabolite recovered from trout bile was identified as either 3′,4′-dichloro-2-hydroxypropionanilide or 3′,4′-dichloro-3-hydroxy-propionanilide. The technical grade propanil also contained 0.67 mg·g−1 of 3,3′,4,4′-tetrachloroazobenzene as a contaminant.

Accumulation, sublethal effects, and safe concentration of a refined oil as evaluated with cutthroat trout

Abstract: Cutthroat trout (Salmo clarki) were exposed for 90 days in the laboratory to a refined oil collected from the North Platte River at a seepage site below the American Oil Company refinery at Casper, Wyoming. Fish were exposed to five concentrations and a control, and seven biological responses (survival, growth, gill pathology, liver pathology, caudal fin erosion, caudal fin pathology and swimming performance) were correlated with water concentration and tissue accumulation of petroleum hydrocarbons. Fish in the highest water concentration, 183μg/L total oil, accumulated tissue concentrations of 4.6μg/g total naphthalenes and responded adversely to all seven biological measurements. Cutthroat trout in the lowest water concentration, 24μg/L total oil, had a mean tissue concentration of 1.2μg/g total naphthalenes, but their response was similar to that of the control fish to all seven biological responses. Fish exposed to 39μg/L water concentration accumulated tissue concentrations of 2.7μg/g and responded negatively to 2 of the 7 biological measurements. Therefore, the maximum safe limit for this oil and cutthroat trout is between 24 and 39μg/L.

Hematological dyscrasia in teleosts chronically exposed to selenium-laden effluent

Abstract: Lepomis microlophus (redear sunfish) were collected from Martin Lake, an east Texas reservoir, as well as a reference lake 8 km upstream in the same drainage system. Martin Lake received aqueous selenium-laden effluent from electrical generator plant systems used to collect fly ash, scrubber sludge, and bottom ash; the reference lake received no such effluent (Texas Parks and Wildlife Department, unpublished report). Neutron activation analysis was used to monitor selenium levels in the hepatopancreas (i.e., the liver and associated, disseminated exocrine pancreas), which is one of the major organs used in monitoring selenium exposure. Fish collected from areas adjacent to the selenium-discharge sites in Martin Lake accumulated about 19.8 ppm in the hepatopancreas, compared to approximately 8.4 ppm for fish collected further from the discharge site. Reference redear sunfish accumulated normal levels of 1.8 ppm in the hepatopancreas. Hematological abnormalities were most severe for fish collected from areas adjacent to the selenium discharge site. These abnormalities included altered leukocyte distribution with elevated numbers of hemoblasts, reduced hematocrits, lower hemoglobin concentrations, slightly reduced numbers of erythrocytes, 12% and 23% reductions in mean corpuscular hemoglobin concentration (MCHC) and mean corpuscular volume (MCV), respectively, and microcytic, poikilocytic erythrocytes with elevated numbers of nuclear shadows. These data present a striking illustration of a case in which the hematological characteristics of a freshwater teleost were correlated with selenium accumulation in a critical organ following chronic selenium exposure. Hematological data provided a sensitive indicator of the severity of the impact of selenium-laden generator plant effluent on this teleost species.

Polybrominated anisoles in marine fish, shellfish, and sediments in Japan

Abstract: The concentrations of polybrominated anisoles (2,4-dibromoanisole, 2,4,6-tribromoanisole and pentabromoanisole) were determined in marine fish, shellfish, and sediments collected in Japan. 2,4,6-Tribromoanisole was found in fourteen of 24 fish and shellfish samples, with a range of 0.1–5.4 (Μg/kg (ppb) on a wet weight basis. The concentrations of 2,4,6-tribromoanisole were similar to pentachloroanisole and hexachlorobenzene but about one-hundredth of those of polychlorinated biphenyls. The correlation between 2,4,6-tribromoanisole and polychlorinated biphenyls levels in fish and shellfish samples was statistically significant. 2,4-Dibromoanisole was found in four fish samples, with a range of 0.6–1.3 ppb. However, pentabromoanisole was not found in any samples of fish and shellfish. No polybrominated anisoles were detected in the sediment samples.

Use of small mammals (voles) to assess a hazardous waste site at Love Canal, Niagara Falls, New York.

Abstract: Voles (Microtus pennsylvanicus) were trapped in the immediate area of Love Canal (I), in an area very close to Love Canal (II), and in a reference area (III) about one km from Love Canal. The population densities were low in I, intermediate in II, and high in III. Using ages estimated on the basis of dry lens weights, mean life expectancy from weaning was 23.6 days in I, 29.2 days in II, and 48.8 days in III. Survivorship curves had significantly steeper slopes in I and II than in III. Thus, voles in I and II experienced a higher mortality rate than those in III. Liver and adrenal weights in females and seminal vesicle weights in males were significantly reduced in I compared to III. A fat pool from voles from I and II contained hexachlorocyclohexane and other chlorinated hydrocarbons that were not found in voles from III. These results suggest that relatively sedentary small native mammals may be of use in assessing environments with hazardous contamination.