Showing papers in "Archives of Environmental Contamination and Toxicology in 1986"

Associations between metabolites of aromatic compounds in bile and the occurrence of hepatic lesions in English sole (Parophrys vetulus) from Puget Sound, Washington.

Abstract: Statistical comparisons were made between the relative mean concentrations of metabolites of aromatic compounds in bile (as estimated by a high-performance liquid chromatography/fluorescence detection method) and idiopathic liver lesions in English sole (Parophrys vetulus) from eleven Puget Sound sites. A significant positive correlation was found between prevalences of neoplasms, foci of cellular alteration, megalocytic hepatosis and total hepatic lesions and the concentrations of metabolites of aromatic compounds. These findings provide further evidence of the putative relationship between aromatic compounds and serious idiopathic liver diseases in bottom-dwelling fish.

Distribution of heavy metals and their age-related changes in the eastern great white egret, Egretta alba modesta, in Korea

Abstract: Organ and tissue distribution of eight metals (Fe, Mn, Zn, Cu, Pb, Ni, Cd, Hg) and their age-related changes were investigated in the chick and adult eastern great white egret,Egretta alba modesta, collected in Korea. High concentrations of the metals were found in the liver, kidney, feathers, bone, and skin; low values were found in the muscle and brain. A majority of the metal burdens in the chick and adult egrets existed in the muscle, bone, and feathers; about 50% of the Hg was in the feathers. The concentrations of Fe, Mn, Zn, and Cu in organs and tissues of the chicks characteristically changed with age, and their accumulations depended upon the metabolic turnover. In contrast, the concentrations of Pb, Ni, Cd, and Hg increased with age, suggesting that age or exposure time is a dominant factor. However, the younger stage of the downy chicks showed a rapid accumulation plateau of Pb, Ni, Cd, and Hg, and a dilution effect of these metal concentrations by increased body weight with age also was observed. Furthermore, rapid decreases of the body burden of Mn, Cu, Ni, Pb, Cd, and Hg were found in the fledgling birds, indicating that the metals were excreted via the feathers by moulting. These results indicate that consideration of the growth stage of organs and tissues is necessary for understanding the bioaccumulation processes and the toxicological criteria of the metals.

Polychlorobiphenyl congeners, p,p'-DDE, and sperm function in humans.

Abstract: 170 seminal samples from fertile men, men with idiopathic oligospermia or azoospermia and men status post vasectomy were analyzed for 74 polychlorobiphenyl (PCB) congeners,p,p′-DDE, mirex, and hexachlorobenzene using the technique of glass capillary gas chromatography with electron capture detection. Low concentrations of 32 PCB congeners were measured (mean total PCB residue of 5.8 ng/g wet weight). The application of multiple linear regression analysis to the data is described and the result is critically evaluated. There is a correlation between sperm motility and count. There are indications that the concentrations of three PCB congeners (2,4,5,2′4′5′- and 2,4,5,2′3′4′-hexachlorobiphenyl and 2,4,5,3′4′-pentachlorobiphenyl) are inversely correlated with sperm motility index in samples with a sperm count less than 20 million cells/ml. The implications of the discerned associations are discussed.

Heavy metal toxicity to fish and the influence of water hardness

Abstract: Toxicity tests with rainbow trout confirm that cadmium is less toxic in hard water (96 hr LC50=2.6 mg Cd/L) than in soft water (96 hr LC50=1.3 mg Cd/L). Water quality studies indicate that this is not due to a chemical reduction of available cadmium in hard water and no significant differences in cadmium uptake were detected between fish from the two levels of hardness. Possible explanations for the effect of hardness on heavy metal toxicity to fish are discussed.

In vitro cytotoxicity of metals to bluegill (BF-2) cells.

Abstract: BF-2 cells, an established fibroblastic cell line derived from the caudal fin of bluegill sunfish (Lepomis macrochirus), were exposed to 18 metal salts. Cytotoxieity was assayed by the neutral red (NR) technique. Based on the concentration of metal that reduced the uptake of neutral red by 50% (NR50), the rank order of Cytotoxieity for the cationic metals was silver > mercury > cadmium > zinc > copper > cobalt > nickel > lead > tin > manganese > chromium (trivalent), and for the anionic metal complexes it was arsenite > dichromate > chromate > arsenate > selenite > permanganate > selenate. There was a strong correlation (r = 0.909) between the NR50 ranking for the divalent metal cations and their chemical softness parameters (σp). A good correlation (r=0.833) was also found between thein vitro NR50 Cytotoxieity values for the cationic metals and thein vivo water-borne LC50 values for bluegill. There was no correlation, however, between NR50 and LC50 data for the anionic metal complexes, primarily due to the unusual tolerance, as reported in the literature, of fish for hexavalent chromium salts.

Contaminant trends in lake trout (Salvelinus namaycush) from the Upper Great Lakes

Abstract: Contaminant body burdens in lake trout (Salvelinus namaycush) from the Upper Great Lakes have been monitored since 1970 on Lake Michigan and since 1977 and 1978 on Lakes Superior and Huron by United States Environmental Protection Agency (USEPA), Great Lakes National Program Office and U.S. Fish and Wildlife Service (USFWS), Great Lakes Fishery Laboratory. Analysis of the Lake Michigan data shows that mean polychlorobiphenyl (PCB) concentrations declined from a maximum of 22.91 mg/kg in 1974 to 5.63 mg/kg in 1982. Mean total DDT concentrations declined from 19.19 mg/kg in 1970 to 2.74 mg/kg in 1982. The decline in both contaminants closely followed first order loss kinetics. If the current declines continue, PCB concentrations will decline to the U.S. Food and Drug Administration (USFDA) tolerance of 2.0 mg/kg in 1988. Mean total DDT concentrations will fall to the International Joint Commission (IJC) objective of 1.0 mg/kg by 1991. Mean dieldrin concentrations increased significantly from 0.20 mg/kg in 1971 to 0.58 mg/kg in 1979 before declining to 0.21 mg/kg in 1982. The decline from 1979–1982 followed first order loss kinetics. As this decline is not reflected in other species (bloater chubs, smelt) it will require additional years of monitoring to determine if dieldrin concentrations between 1979 and 1982 truly represents a declining trend. The only statistically significant trend other than in Lake Michigan was for total DDT which declined significantly in Lake Superior lake trout. Large data variance and the short time frame covered (1977–1982) interfered with detection of trends on Lakes Superior and Huron.

Influence of aquatic humus on the bioavailability of chlorinated micropollutants in Atlantic salmon.

Abstract: The possible influence of natural humic water on the uptake of 2,4,6-trichlorophenol, tetrachlorguaiacol, lindane and 2,4′,5-trichlorobiphenyl in Atlantic salmon underyearlings has been studied, using a semistatic test procedure. Springtime humus water reduced the bioconcentration factors for both the 2,4,6-trichlorophenol and lindane about 18 percent compared to lake water. No reduction in the bioconcentration factor was observed for tetrachloroguaiacol. Autumn humus water reduced the bioconcentration factor of 2,4′,5-trichlorobiphenyl 30 percent compared to lake water, while no reduction was observed for lindane. The results have shown that natural humus water can reduce the bioavailability of organic micropollutants towards fish. The effect is different for different compounds and also depends on the nature of the humus.

Sources of mercury contamination in the sediments of small headwater lakes in South-Central Ontario, Canada

Abstract: To determine the significance of mercury contamination of remote lakes in three regions of south-central Ontario, Canada, sediment cores were collected at several stations in each of fourteen lakes. Profiles of Hg concentration with depth were similar to those found in many parts of the world and indicate a substantial increase in Hg loading to these lakes in recent decades. Surficial sediment concentrations (0–2 cm) ranged from 120 to 700 ng/g dry matter.

Selenium uptake and transfer in an aquatic food chain and its effects on fathead minnow larvae

Abstract: The transfer of Se (Na2SeO4) was followed through a laboratory food chain (wateralgae-rotifer-larval fish) and its effect on larval fathead minnows (Pimephales promelas). Selenium transfer between algae (Chlorella pyrenoidosa) and rotifers (Brachionus calyciflorus) was a function of time and food availability. Selenium concentrations in the rotifers ranged from 46 to 91Μg Se · g−1 dry weight after 5 hr of feeding. Selenium concentrations (±SD) in larval fish reached 61.1±1.1 Μg Se · g−1 dry weight for 9 day-old larvae and 51.7+1.6 Μg Se · g−1 for 17 day-old larvae after 7 and 9 days of feeding with Se-contaminated rotifers, respectively. Final dry weights of larvae fed Se-contaminated rotifers were significantly lower than those of controls, although acute toxicity (mortality) was not demonstrated. The biological halflife of food-derived Se in the larvae was 28 days.

Concentrations and chromatographic profile of DDT metabolites and polychlorobiphenyl (PCB) residues in stranded beluga whales (Delphinapterus leucas) from the St. Lawrence estuary, Canada

Abstract: The concentrations and high resolution gas Chromatographic profiles of DDT metabolites and polychlorobiphenyl (PCB) congeners were determined in blubber, liver, kidney and lung tissue and milk samples of stranded beluga whales (Delphinapterus leucas) collected at localities along the coasts of the Saint Lawrence Estuary, Canada from November 1983 through December 1984. The analyses indicate that the major PCB components of the tissues were 2,2′,5,5′-tetra-, 2,2′,4,4′,5-penta-, 2,2′,3,4,4′,5′-hexa-, 2,2′,4,4′,5,5′-hexa-, 2, 2′,3,3′,4,5-hexa-, 2,3,3′,5,5′,6-hexa-, 2,2′,3,4, 5,5′,6-hepta- and 2,2′,3,4,4′,5,5′-heptachlorobiphenyls. Although the highest organochlorine chemical concentrations were found primarily in the blubber, concentrations of 1.72 Μg/g for PCB and 2.04 Μg/g for ⌆DDT were determined in one milk sample. No correlation was established between PCB,p,p-DDE and ⌆DDT concentrations and the fat content of the kidney liver and lung tissues. The Chromatographie patterns of the PCB congeners were similar from one tissue to another with the exception of the kidney; the profile indicates the retention of PCB congeners which are minor components in the other tissues. Relations of residue concentrations between tissue are described and the significance of congener-specific PCB analysis is discussed in terms of the structureactivity effects on PCB persistence and toxicity.

Cadmium kinetics in freshwater clams. I. The pattern of cadmium accumulation in Anodonta cygnea

Abstract: Freshwater clams (Anodonta cygnea) were exposed to cadmium under laboratory conditions. Time courses of Cd accumulation were determined for whole animal and the separate organs. At 5 Μg/L, Cd accumulation proceeded mainly linearly. At 25 Μg/L, the accumulation pattern was biphasic for whole animals and most of the organs: during the first four weeks Cd concentrations increased linearly, remaining at a constant level for the next two weeks. Thereafter, metal concentrations increased strongly until, after 10 weeks, a saturation level was reached. It is argued that the biphasic course of accumulation is not caused by an advancing selection through mortality or by the gradually decreasing mean animal weight, nor by the typical laboratory conditions of absence of food and substratum. The partition of total Cd among the organs gradually changed over the first eight weeks, remaining constant from that time. The ultimate order of Cd concentrations was: gills > labial palps > mantle-edge > mantle, kidney, whole animal > midgut gland > guts/gonads complex > foot. A possible relation between the time course of Cd accumulation and behavioral responses is presented.

Factors affecting the exposure of ground-rig applicators to 2,4-D dimethylamine salt.

Abstract: This is a report on exposure to and absorption of the herbicide 2,4-D dimethylamine salt by farmers carrying out spray operations with tractor-drawn ground-rigs, involving handling, transferring, mixing, and applying the herbicide to wheat. The 30 individual spray operations lasted 55 to 870 min, and involved 1 to 11 tank fills, and application of 6.7 to 88.3 kg 2,4-D (acid equivalent, a.e.) to 16 to 194 ha.

Reduced reproduction of wedge-tailed shearwaters exposed to weathered Santa Barbara crude oil

Abstract: Wedge-tailed Shearwaters breeding on Manana Island, Hawaii were treated with 0.1–2.0 ml weathered Santa Barbara crude oil either by external application to the breast plumage or by oral dose in gelatin capsules approximately 30 days prior to egg laying. Applications of oil caused reduced lay, lowered hatching success, and reduced breeding success. Two ml applied externally to the breast plumage resulted in a greatly reduced number of eggs laid and complete hatching failure of 60 pair of exposed birds. Oral doses of oil in gelatin capsules reduced laying and breeding success, but to a lesser extent than external exposure. Oil exposure did not change the length of the prelaying exodus or cause birds to move to new areas of the breeding colony, but resulted in abandonment and reduced incubation attentiveness. Growth rates of chicks of oral dosed birds were not different from controls, although survival of chicks of dosed birds was reduced. Long-term effects of external application of 2.0 ml of oil were demonstrated by a decreased number of birds returning to the colony in the year after dosing and reduced breeding success one year after oil exposure.

Wildlife in some areas of New Mexico and Texas accumulate elevated DDE residues, 1983

Abstract: Over the last decade, data gathered by the U.S. Fish & Wildlife Service's National Contaminant Biomonitoring Program have identified an area of elevated DDE contamination in portions of New Mexico and Texas. Extensive wildlife sampling in 1983 confirmed that DDE, the major metabolite of the insecticide DDT, was present at high concentrations in wildlife at selected sites in the Rio Grande and Pecos River drainages. DDE in carcasses ranged up to 47 ppm (wet weight) in western kingbirds (Tyrannus verticalis), 35 ppm in house sparrows (Passer domesticus), 46 ppm in Brazilian free-tailed bats (Tadarida brasiliensis), and 104 ppm in whiptail lizards (Cnemidophorus spp.). DDE was also detected in gut contents from western kingbirds at some of the highest concentrations ever reported, ranging up to 21 ppm in proventricular samples. An average of 40% of the eggs of black-crowned night-herons (Nycticorax nycticorax) from two sites along the Pecos River in New Mexico had DDE levels (≥8 ppm) that have been associated in other studies with impaired reproduction. In contrast, wintering mallards (Anas platyrhynchos) and American coots (Fulica americana) from the study area did not accumulate elevated DDE levels. DDE in wildlife samples at control sites (nonagricultural areas) was either absent or averaged less than 0.35 ppm.

Growth of Asiatic clams (Corbicula sp.) during and after long-term zinc exposure in field-located and laboratory artificial streams

Abstract: Juvenile and adult Asiatic clams were exposed to 0.025-1.0 mg Zn/L for 30 days in artificial stream systems in an outdoor field laboratory and formal laboratory setting. All exposures (≧0.050 mg/L), except 0.025 mg/L, significantly reduced total weight gain between days 20 to 30 in the field-laboratory experiments. Laboratory exposures yielded little growth information as nutritional needs of the clam were not adequately satisfied; therefore, further research was confined to the field location. Exposures to 1.0 mg/L resulted in 10-50% mortality by day 30 in outdoor artificial streams. Significant increases in tissue water content of Zn-exposed clams indicated tissue degradation or osmoregulatory impairment. Bioaccumulation of Zn occurred at all levels of exposure and reflected growth inhibition at the levels tested. The maximum accumulation occurred in 1.0 mg/L treated clams (2000 Μg Zn/g dry weight). Controls varied consistently around 200 Μg Zn/g dry weight. When clams exposed to Zn (0.050-1.0 mg/L) were removed from exposure to control streams, Zn was completely depurated in 17 days with a concomitant return to normal growth patterns. Clams from the higher Zn exposures (0.50 and 1.0 mg/L) remained significantly different from controls due to earlier growth inhibition by Zn.Corbicula is a sensitive indicator of Zn stress at levels that are currently considered protective of aquatic life.

The acute and chronic toxicity of cadmium to different life history stages of the freshwater crustacean Asellus aquaticus (L)

Abstract: Different life-history stages of the freshwater isopod crustaceanAsellus aquaticus were exposed to a range of cadmium concentrations using a semi-static toxicity testing procedure. Median lethal concentrations (96-hr LC50) ranged from 80 Μg Cd/L for juveniles to >2,000 Μg Cd/L for embryos. Pre-treatment of eggs with cadmium did not increase their tolerance to the metal as juveniles. The responses of each stage are discussed in relation to the use of macroinvertebrate toxicity test data in predicting the hazardous effects of pollutants.

Transfer and distribution of accumulated (14C)polychlorinated biphenyls from maternal to fetal and suckling rats

Abstract: (14C)polychlorinated biphenyls [PCBs (KC-600)] were administered orally to female rats at the dose of 10 mg/kg in olive oil once a week for five weeks. Four weeks after the last administration of (14C)PCBs, they were mated with untreated males. The distribution of total14C was examined in maternal and offspring tissues. The average amount of PCBs accumulated in dams was 44.2% of the dose two weeks after the last administration. The average amount transferred from dam to fetus was 0.003% accumulated in the dam. In the fetus, the highest concentration was found in the fetal placenta followed by the liver, heart, skin, muscle, blood, lung, and brain. The PCBs level in fetal blood was the same as in maternal blood. The average concentration of PCBs in milk was 1.84 ppm. The amount transferred to sucklings increased gradually to about 5% of the maternal PCBs. In suckling rats, PCBs were distributed at the highest concentration in adipose tissues and at intermediate concentrations in the skin, adrenal gland, and liver. The liver to body weight ratio of offspring was significantly increased on the 11th and 25th days after birth. The nursing rats had lower PCBs concentrations compared with the pregnant and virgin rats. The organ concentrations of PCBs in dam and offspring were about ten times as high as those found after treatment with Kane-chlor®-400. These results may suggest that PCBs with higher chlorine content remained in tissues for a longer period of time.

Bioaccumulation of polychlorinated biphenyls and metals from contaminated sediment by freshwater prawns, Macrobrachium rosenbergii and clams, Corbicula fluminea.

Abstract: Freshwater prawns,Macrobrachium rosenbergii, and clams,Corbicula fluminea, were exposed for 48 or 50 days to three concentrations of a river sediment that contained environmental contaminants such as polychlorinated biphenyls (PCBs) and metals. Sediment was obtained twice during 1980 from the same location. Prawns were exposed to the first batch, sediment 5–80, which contained higher concentrations of some metals and PCBs compared to sediment 11–80, used with the clams. The highest concentration of sediment 5–80 was toxic to the prawns; sediment 11–80 was not toxic to the clams. Tissue analyses of prawns for PCBs, as Aroclors® 1242 and 1254, demonstrated bioaccumulation. Maximum concentration of 1242 in prawns was achieved by day 7 while 1254 continued to accumulate in prawn tissues during the initial 40 days of the exposure period. The PCB sediment bioaccumulation factors (BAF) for prawns ranged from 0.11 to 0.90 for 1242 and 0.20 to 2.40 for 1254, and were highest for animals exposed to 10% sediment. Exposed clams also accumulated PCBs (1242 + 1254) from the sediment. Sediment BAFs for clams were 0.54 to 12.52 and were highest for animals exposed to 10% sediment. Analyses of clams for metals showed lead (Pb) in exposed animals at higher concentrations compared with controls. Bioaccumulation of Pb differed from PCB in that the Pb concentrations did not increase over time and concentrations were higher among animals exposed to 10% sediment compared to animals exposed to 100% sediment. Sediment 11–80 contained 99 mg/kg of Pb while exposed animals, at 48 days, contained approximately 2.2 mg/kg Pb. Analysis of clams for cadmium (Cd) showed exposed animals contained less Cd than controls.

Dicofol exposure to Florida citrus applicators: effects of protective clothing.

Abstract: Mixer-loaders and applicators of the pesticide dicofol in Florida citrus groves were monitored for exposure. Alpha-cellulose pads were placed inside and outside regular work clothing. When protective suits were in use, pads were also placed outside the suit. Dicofol accumulation rates were measured when gloves and/or facemasks were worn. Hand rinses were collected. Results showed that an ungloved, normally attired applicator reduced his total dermal exposure 38% by wearing a disposable Tyvek® protective suit, 27% by wearing gloves, and 65% by wearing both. Suits reduced total dermal exposure by 40% for mixer-loaders, but the use of gloves led to an exposure increase, probably because the inside of the gloves became contaminated.

A congener analysis of polychlorinated biphenyls accumulating in rat pups after perinatal exposure

Abstract: Rat pups were exposed to polychlorinated biphenyls (PCBs) from conception to weaning. Exposure occurred via feeding dams adulterated certified chow that was designed to contain 0, 3, 30, and 300 Μg/gm Aroclor® 1254. Tissue samples from rat pups and dams were analyzed for 67 different PCB congeners at birth and weaning to describe their accumulation during gestation and lactation. Bioaccumulation of PCB congeners was calculated as a function of their concentration in feed or milk. These data indicated that PCB congeners could be divided into three different groups. The “a” group was not avidly bioaccumulated. Congeners in the “b” group accumulated to widely different concentrations. This group contained primarily penta- and hexachlorinated biphenyls. The analysis of two families of pentachlorobiphenyls containing one ring with −2,3,4, or −2,4,5 chlorine substitutions indicated that molecular structure and not physico-chemical properties,e.g., gas Chromatographic retention time, determined bioaccumulation. The “c” group were all highly chlorinated congeners and bioaccumulated to nearly equal levels. Most congeners were concentrated in the milk when compared to the feed. When bioaccumulation data from pups at birth and weaning were compared, exposure was much greater during lactation than during gestation. The congener analysis showed that the same congeners were most avidly bioaccumulated during the periods of gestation and lactation, indicating that the increased accumulation during lactation was due to a higher effective dose.

Cadmium kinetics in freshwater clams. II. A comparative study of cadmium uptake and cellular distribution in the unionidae Anodonta cygnea, Anodonta anatina, and Unio pictorum.

Abstract: A comparative study was made of Cd accumulation in three species of Unionidae. Up to eleven weeks of exposure, patterns of accumulation in whole animal were biphasic and didn't differ essentially between the species. After the eleventh week, Cd uptake increased strongly inA. anatina, whereas inA. cygnea metal concentration remained at a constant level. This dissimilarity is discussed in terms of differing ventilation activity. Large differences were observed between corresponding organs of the species with regard to the Cd concentration (on the basis of organ dry weight). However, when comparing the normalized burden values (on the basis of total dry weight) differences were found to be small. In conclusion, in the comparison of related species, normalized burden rather than concentration has to be considered as the more realistic parameter of Cd accumulation. Comparing mussels of different condition (summer and winter animals) of the same species, accumulation patterns diverged when the parameter of Cd concentration was used, but not with the parameter of Cd burden; the total body or organ mass factor holds elements of differing, seasonally dependent weight (e.g., energy stores) that do not affect the extent of Cd uptake. Cd amounts and Cd concentrations (on a protein basis) were highest either in the nuclear fraction or in the cytosol in the two Anodonta species, depending on the organ. In gillsof A. anatina, and in midgut gland ofA. cygnea, 75% of total organ Cd was found in the nuclear fraction. A possible contribution of large membrane-limited vesicles and of calcium concretions to this fraction is discussed. Only in the kidney of either species was the amount of cytosolic Cd greater than that in the nuclear fraction. In the other cases, the ratio of Cd amounts in the nuclear and cytosolic fractions was about 3∶2. Partition of Cd between the total particulate and the non-particulate fraction was similar at 5 and 16 weeks of exposure. After gel filtration, total cytosolic Cd was recovered in a high-molecular weight (HMW) fraction and in a protein fraction with apparent MW of 11 kD. In gills, mantle, and midgut gland, the contribution of the latter fraction increased with exposure time.

The precision of daphnid ( Daphnia magna Straus, 1820) static acute toxicity tests

Abstract: Three repiicate 48-hr static acute toxicity tests were conducted withDaphnia magna Straus 1820 for each of seven test chemicals (chlorobenzene, chloroform,p-dichlorobenzene, diethanol-amine, epichlorohydrin, ethylene glycol and phenol). The ratios of the highest to lowest LC50 values for a particular chemical ranged from 1.05 to 1.44 with a mean ratio for all seven chemicals of 1.27±0.13 (coefficients of variation averaged approximately 4%).

Interaction of benzo(a)pyrene and cadmium on GSH-S-transferase and benzo(a)pyrene hydroxylase in the black sea bass Centropristis striata

Abstract: The effect of benzo(a)pyrene (BaP) and cadmium (Cd) upon the hepatic enzymes, BaP hydroxylase and GSH-S-transferase, was investigated in black sea bass. Intraperitoneal (ip) injections of BaP produced a significant increase in BaP hydroxylase activity in the microsomal fraction and GSH-S-transferase activity in the cytosol. Administration of Cd alone had no effect on either enzyme. However, when both Cd and BaP were injected (ip) in the fish, Cd had an inhibitory effect on the activity of these hepatic enzymes. Pretreatment of fish with a low dose of Cd (0.42 mg/kg) prior to injection of BaP and Cd produced a 30% increase in GSH-S-transferase activity and a 50% reduction in BaP hydroxylase activity when compared to fish injected with BaP alone following Cd pretreatment. Thus, a low dose of Cd was effective in producing a tolerance to a subsequent Cd challenge for the enzyme GSH-S-transferase but not for BaP hydroxylase. In contrast, fish pretreated with a high dose of Cd (2.5 mg/kg) prior to BaP treatment alone or with Cd displayed no difference in either enzyme activity. The implications from this study on the exposure of black sea bass to two xenobiotics, Cd and BaP, indicate that BaP hydroxylase may not serve as a good monitor for hydrocarbon pollution in the presence of Cd.

Metal interactions within the kidney, gill, and digestive gland of the hard clam, Mercenaria mercenaria, following laboratory exposure to cadmium.

Abstract: Mercenaria mercenaria were exposed to 0.1 Μg Cd/ml seawater (109Cd + stable carrier) for either (1) periods of 1 hr to 31 days, or (2) a period of 3 days followed by depuration in clean seawater for 2 to 64 days. Cd accumulated at increasing rates in the kidney, but at decreasing rates in all other organs of the clam during the laboratory exposure period. Measurement of total Cd levels confirmed that109Cd was accumulated by the clam tissues and not simply exchanged. The overall rate of Cd accumulation was significantly greater (P 0.05). No loss of Cd or other detectable metals occurred even after 64 days depuration. The degree to which Cd accumulated in the kidney, gill, and digestive gland did not correlate with the concentrations of other metals already present in these organs (except with Zn in the digestive gland). Negative correlations between different metal concentrations were never observed. Comparison of metal interaction patterns between the kidney, gill, and digestive gland indicates that each organ relies on different mechanisms for sequestering metals.

Effects of environmental contaminants on snapping turtles of a tidal wetland

Abstract: Snapping turtles (Chelydra serpentina) were collected from a brackish-water and a nearly freshwater area in the contaminated Hackensack Meadowlands of New Jersey and an uncontaminated freshwater area in Maryland to determine the effects of environmental contaminants on a resident wetland species. No turtles were observed or caught in the Meadowlands at two trapping sites that were the most heavily contaminated by metals. Snapping turtles from the brackish-water area had an unusually low lipid content of body fat and reduced growth compared to turtles from the fresh-water areas in New Jersey and Maryland. Despite the serious metal contamination of the Hackensack Meadowlands, the metal content of kidneys and livers from New Jersey turtles was low and not greatly different from that of the Maryland turtles. Organochlorine pesticide concentrations in body fat were generally low at all three study areas. Polychlorinated biphenyls (PCBs) concentrations in fat were highest in male turtles from the New Jersey brackish-water area. Analysis of blood for amino-levulinic acid dehydratase, albumin, glucose, hemoglobin, osmolality, packed cell volume, total protein, triglycerides, and uric acid failed to reveal any differences among groups that would indicate physiological impairment related to contaminants.

Uptake and tissue distribution of mercury in some plant species collected from a contaminated area in India: Its ecological implications

Abstract: A study was made of the pattern of distribution of mercury in the tissues of some plant species collected around a chlor-alkali factory in India. Different plants accumulated different levels of mercury in their tissues. Accumulation in leaves was the highest, followed by the stem and the root and, in some cases, the root and the stem. A significant correlation was noted between the mercury concentration of the soil and the plant tissues and between different tissues. Grazers (goats, sheep) also accumulated significant levels of mercury in their tissues.

Atrazine uptake, photosynthetic inhibition, and short-term recovery for the submersed vascular plant, Potamogeton perfoliatus L.

Abstract: The processes of atrazine (2-chloro-4-[ethylamino]-6-[isopropylamino-]-s-tri-azine) uptake and release in the submersed vascular plant,Potamogeton perfoliatus L., were rapid, approaching equilibrium with the surrounding environment within one hr. The ratio of internal atrazine concentration to external concentration was approximately 10 at the point of maximum photosynthetic inhibition and rapidly increased at lower external atrazine concentrations. The I50 (the concentration inhibiting photosynthesis by 50%) for atrazine in solution was 80 μg/L with the maximum observed photosynthetic reduction (87%) at a solution concentration of 650 μg/L. Initial photosynthetic recovery ofP. perfoliatus following exposure to atrazine was rapid with oxygen evolution from treated plants (5, 25, and 100 μg/L) being statistically indistinguishable from control plants after two hr of atrazine-free wash. However, there was an indication of residual photosynthetic depression in dosed plants, even after a 77 hr recovery period. In Chesapeake Bay, potential long-term exposure of submersed plants to concentrations of atrazine greater than 10 μg/L is doubtful so that reduction ofP. perfoliatus photosynthesis under such conditions would be minimal and reversible.

Determination of genotoxic polycyclic aromatic hydrocarbons in a sediment from the Black River (Ohio).

Abstract: Polycyciic aromatic hydrocarbons (PAH) have been identified as genotoxic pollutants in sediment from the Black River, Ohio, where a high incidence of hepatoma was observed in brown bull-head catfish (Ictalurus nebulosus). Subfractions of PAH based on the number of aromatic carbons were isolated from the PAH fraction of a Black River sediment extract. Ten subfractions were analyzed by capillary column gas chromatographymass spectrometry, tested for mutagenicity using the Ames assay, and tested for induction of unscheduled DNA synthesis (UDS) in primary rat hepatocytes. The Ames assay indicated significant mutagenic activity in fractions which contained PAH with 4–6 aromatic rings; the majority of the activity was found in the fraction composed of 5-ring compounds. UDS was also significant in the same fractions, although the greatest genotoxicity was observed in thecata-condensed andperi-condensed 4-ring fractions which contained a large amount of alkylated-PAH.

Uptake of polychlorobiphenyl congeners by purple loosestrife (Lythrum salicaria) on the banks of the Hudson river

Abstract: Transport of 42 polychlorobiphenyl (PCB) congeners by purple loosestrife (Lythrum salicaria) in two ecosystems is reported. The contaminated site was beside the Hudson River at Albany, New York, and the control site was two miles distant on wasteland. By transplanting and translocating the plants between the sites, systemic uptake from the roots and uptake from the air were determined. Uptake from ambient air was also measured with a 0.2-m3 field sampling chamber. The dominant route of uptake by the plant was via the roots. At high ambient concentrations (140 ng/m) PCB was scavenged from the air by the plants. At low ambient concentrations (8 ng/m3) 2-chlorobiphenyl and 2,2′-dichlorobiphenyl were emitted by the plants.

Quantitative ultrastructural changes associated with lead-coupled luxury phosphate uptake and polyphosphate utilization

Abstract: Quantitative electron microscopy (stereology) was used to assess the ultrastructural response of three algae representative of the classes Chlorophyceae, Cyanophyceae, and Bacillariophyceae to lead-coupled polyphosphate degradation. The organisms were exposed to a culture medium concentration of 20 ppb Pb for 3 hr at the time of luxury phosphate uptake and subsequently transferred to phosphorus and lead-free medium. A differential sensitivity was observed as follows:Plectonema > Scenedesmus > Cyclotella. InPlectonema andScenedesmus, detrimental cytological changes were observed when the polyphosphate relative volume dropped below 0.5%, which was approximately the P-starvation level of polyphosphate. Few significant ultrastructural changes were observed inCyclotella after one week in P-deficient medium. At this time, the relative volume of polyphosphate was still 1.5%. Although a few significant ultrastructural changes occurred with phosphate deprivation, the greatest numbers of changes occurred in cells that had been exposed to a short-term (3 hr) low level of Pb. Changes in the relative volume of polyphosphate in all three organisms suggest thatPlectonema andScenedesmus have higher phosphate nutrient requirements thanCyclotella. The ecological implications of metal sequestering by polyphosphate are discussed.