Showing papers on "Bioaccumulation published in 1980"

Relationship between biotransformation and the toxicity and fate of xenobiotic chemicals in fish.

Abstract: Many of the biotransformation reactions which have been described for xenobiotic substances in mammals have been demonstrated in fish in both in vitro and in vivo experiments. Several of these biotransformation reactions have been shown to occur in fish at rates which are sufficient to have significant effects on the toxicity and residue dynamics of selected chemicals. Inhibition of these reactions can lead to increased toxicity and bioaccumulation factors for certain chemicals. Several classes of compounds, including some polychlorinated biphenyls, are metabolized slowly, and their disposition in fish may not be influenced to any great extent by biotransformation. Metabolites of compounds which are biotransformed rapidly may appear in certain fish tissues, and in many instances these are not accounted for by conventional residue analysis methods. Microsomal mixed-function oxidases in several species of fish have been demonstrated to be induced by specific polycyclic aromatic hydrocarbons and by exposure of fish to crude oil. Induction of these enzymes in fish can result in both qualitative and quantitative differences in the metabolic disposition of xenobiotics to which fish are exposed.

Comparative toxicity of arsenic compounds and their accumulation in invertebrates and fish

Abstract: The toxicity of arsenic III, arsenic V, sodium dimethyl arsenate, and disodium methyl arsenate to stoneflies, snails, amphipods, and trout, and the bioaccumulation of these compounds were studied during a 28-day flow-through test.Daphnia magna were exposed for 21 days in static tests to determine life-cycle effects. All animals were exposed to concentrations of approximately 100 and 1000μg/L (as arsenic) of each of the compounds. Arsenic III, the most toxic compound, caused a significant reduction in the survival of amphipods at 1000μg As/L after seven days. None of the compounds significantly affected the survival of other test species after 28 days or reduced young production inDaphnia after 14 days of exposure. The concentration of accumulated arsenic in stoneflies, snails,and Daphnia was as much as 131, 99, and 219 times greater than the water concentration, whereas amphipods and rainbow trout contained arsenic residues similar to the controls. Residues in stoneflies, snails, andDaphnia exposed to 1000μg As/L were higher than those in animals exposed to 100μg As/L, but appeared to reach a steady state after 14 days. Total arsenic accumulation was greatest in organisms exposed to inorganic arsenic, particularly at 100μg/L.

Toxicity and bioaccumulation of cadmium in the colonial green alga Scenedesmus obliquus.

Abstract: A laboratory investigation was conducted to study the extent and efficiency of cadmium bioaccumulation inScenedesmus obliquus by subjecting this alga to varied sublethal Cd concentrations. The influence of cell population age on Cd bioaccumulation was also studied. Under the experimental conditions employed, growth was not significantly affected by Cd concentrations ranging from 0.01 ppm to 1.00 ppm. At concentrations above 1.00 ppm, however, growth was inhibited markedly. Increases in external Cd concentration caused an increase in total bioaccumulation over the entire range of concentrations, which did not significantly affect growth. Efficiency of Cd bioaccumulation was also concentration dependent, but maximum accumulation efficiency occurred in a medium with a Cd concentration lower than that medium in which maximum total bioaccumulation occurred. Age of the cell population influenced the extent of Cd bioaccumulation. Rapidly growing, young cultures accumulated less Cd than older cultures approaching stationary growth phase.

The Acute Toxicity and Bioaccumulation of Some Lead Alkyl Compounds in Marine Animals

Abstract: The acute toxicity of a range of alkyl lead compounds including tetra methyl and tetra ethyl lead and their tri alkyl and di alkyl degradation products has been determined with four marine phyla. An alga ( Phaeodactylum tricornutum ), a mollusc ( Mytilus edulis ), a crustacean ( Crangon crangon ) and a fish ( Pleuronectes platessa ). The accumulation of the relatively stable trialkyl lead compounds has also been determined in a mollusc ( Mytilus edulis ) and a fish ( Limanda limanda ). The evidence suggests that the major environmental impact of a release of tetra methyl or tetra ethyl lead into the marine environment is likely to be due to acutely toxic effects rather than to those of bioaccumulation.

Comparison of Heavy Metal Interactions in Acute and Artificial Stream Bioassay Techniques for the Asiatic Clam ( Corbicula fluminea )

Abstract: Population densities of the Asiatic clam, Corbicula fluminea, in the thermally influenced areas of the New River at the Glen Lyn power plant, Glen Lyn, Va., increased from zero before 1975 to approximately 11 522/m 2 by February 1978. Since their establishment, clams in the thermal effluent have served as a source of propagules for clam invasion into other areas of the New River during the warmer seasons. Copper was more toxic (LC 5 0 = 0.04 ppm) to the clam than zinc (LC 5 0 = 6.04 ppm) or copper-zinc simultaneously (LC 5 0 = 0.05 ppm) in 96-h static bioassays. Ninety-six-h LC 5 0 determinations in artificial stream bioassays were at least one order of magnitude higher when compared with the static test values (the LC 5 0 values for copper and copper-zinc combined were 0.49 and 3.06 ppm, respectively). The LC 5 0 values appeared also to be the effective concentration at which at least 50 percent of the clams demonstrated a gaping response and cessation of filtering activity. Elemental bioaccumulation of copper and zinc was more prevalent in the visceral tissue than in concentrations measured from clam valves or from the water in both laboratory bioassays and field determinations. When copper bioaccumulation in the viscera increased to approximately 275 to 400 ppm, gaping and a lack of filtering activity were evident in 96-h tests. Behavioral mechanisms-cessation of filtering activity and the closure of valves during stress-were considered to be likely factors in producing the higher LC 5 0 values, when compared with other invertebrate responses.

The Effects of Acidity on the Uptake of Mercury in Fish

Abstract: The effect of pH on the transformation, transport, and bioaccumulation of mercury are discussed. Through its effect on mercury retention in the water-body, and on the biomass and growth rate of aquatic organisms, low pH leads to higher mercury levels in fish. For a better understanding of mercury turnover and transport, however, greater knowledge concerning re-emission of mercury from both land and water is required.

The bioaccumulation factor for phosphorus-32 in edible fish tissue. Final report 1 Aug 77-15 Oct 79

Abstract: Information used to derive the bioaccumulation factor for P-32 in edible portions of fish from water was reviewed to evaluate the currently recommended values of 100,000 in fresh water and 29,000 in sea water that are applied in generic calculations of radiation doses to persons from nuclear power reactor effluents. A phosphorus bioaccumulation factor of 70,000 was calculated for larger rivers and estuarine waters on the basis of geometric mean phosphorus concentrations of 2 mg/g wet weight in fish muscle and 0.03 mg/1 dissolved in water. A bioaccumulation factor for P-32 of 3,000 was computed by multiplying the phosphorus bioaccumulation factor by the ratio of the biological to the effective turnover rate in fish muscle. A biological turnover rate in muscle of 0.2 percent per day was estimated from phosphorus balances as a long-term average for large fish, although more rapid turnovers have been observed for brief periods. Large deviations from these selected generic bioaccumulation factors occur because of differences in phosphorus concentrations and turnover rates. Bioaccumulation of this magnitude is due to P-32 concentration at lowest trophic levels in the food web, not by concentration in fish, hence the availability of concentrating organisms determines whether this bioaccumulation factor ismore » reached. Several other conditions that affect the P-32 bioaccumulation factor have not been quantified but are suggested for study. Measurement programs are recommended to determine site-specific P-32 bioaccumulation factors and enlarge the data base for the generic values.« less

Aqueous Effluent Concentration for Application to Biotest Systems

Abstract: Potential chemical mutagens in industrial effluents may be present at concentrations below the detection limits of biotests such as the Ames mutagenicity test. These chemicals may accumulate in biological food chains. Many insecticides and other chemicals are known to accumulate in living organisms where tissues act as effective storage depots for toxic compounds (Loomis, 1978). This effect is especially significant for human health when dilute toxicants enter the human food chain, such as through seafoods. Mollusks such as the oyster tend to accumulate toxicants, because they filter-feed, which concentrates and magnifies the effects of toxic materials. Because of this potential for bioaccumulation, methods are needed to determine the bioactivity of low concentrations of potential toxicants in industrial effluents.

Experimental study of the bioaccumulation of inorganic mercury and methylmercury in the goldfish (Carassius auratus L.)

Abstract: The study of the mercury and methylmercury bioaccumulation by various species of fish is only possible experimentally when the animals are maintained fasting during a few days. With a such experimentation in the goldfish (Carassius auratus L.), the authors are showing that methylmercury is much more accumulated than inorganic mercury: the transfert factor is about 760 to 780 for the methylmercury chloride and only 90 for the mercuric chloride. In fact a lot of variables occur in this phenomena of bioaccumulation (experimentation time, size and age of fish, solvant space, concentration of oxygen and mercury in water,...) and make this study difficult.

Transpiacental Bioaccumulation of Organoarsenate in Rat-Fetal Blood after Ferric Methanearsonate Administration

Abstract: 妊娠11日目または19日目に Wistar 系ラットに14C-メタンアルソン酸鉄 (20mg/kg) を1回経口投与し, 全身オートラジオグラフィーと放射能分析によって妊娠20日目まで経時的に胎仔移行性を調査した. 胚期以降の妊娠段階で投与された場合, 放射性炭素は投与後の経過時間にかかわりなく妊娠末期の成熟胎仔に特異的に蓄積した. 成熟胎仔中での放射能の分布は成熟雄ラットとほぼ同様であり, 血液が最大の分布組織となっていた. この胎仔血親和性の放射性物質はジメチルアルシン酸と考えられ, 胚の発達に毒性学的な悪影響は及ぼさないと思われる.

Biological Assessment of Upper Mississippi River Sediments.

Abstract: : The objective of this study was to determine the potential for polychlorinated biphenyls (PCB) and metals to bioaccumulate in the tissues of fish and invertebrates as a result of exposure to sediment from various dredging sites in the upper Mississippi River area. The acute toxicity of these sediments was of secondary interest. Water fleas (Daphnia), catfish, and bluegills were exposed to suspensions of fine-grained sediment from three test sites and one reference site for 4 to 6 days, approximately the duration of a typical dredging and disposal operation on the upper Mississippi River. Survival and tissue concentrations of contaminants in fish were determined after exposure. Fawnfoot and three-ridge clams, mayfly larvae, and amphipods were exposed to deposited sediments for up to 14 days, after which survival and contaminant concentrations in tissues of clams were determined. All three test sediments were of low toxicity to all species except the amphipods, in that no sediment produced statistically greater mortality than occurred in the controls and reference sediment. Although statistical comparisons were not made, amphipod mortality in some Upper Mississippi River sediments apparently exceeded that in the controls but probably not that in the reference sediment. Bioaccumulation was the exception, rather than the rule, with 72 species-sediment-contaminant combinations being studied and bioaccumulation potential being indicated in 8 (11 percent) of the cases. Even in these cases, resulting concentrations were below those considered likely to cause adverse impacts.

An Environmental Study of the Origin, Distribution, and Bioaccumulation of Selenium in Kentucky and Barkley Lakes

Abstract: Many samples of water, bottom sediment, and fish were analyzed for toxic metal ion content. The samples were collected from several selected sites along Kentucky and Barkley Lakes as well as the Cumberland River and several sub-impoundments along these aquatic systems. Emphasis was placed on selenium, although several other metal ions were determined. The results showed that there are no serious pollution problems with As, Cd, Cr, Cu, Hg, Pb, Se, Sr, Zn, or Zr at any of the sites e.vam1ned. Actually, none of the trace metals examined even come close to the EPA limits on fish, with the exception of lead in the White Crappie and mercury in the Bass. There appears to be no serious problem with lead in White Crappie as only two fish out of a total of nineteen were above the limit of 2 PPM. The same holds for mercury in the bass as only three fish out of thirtyfour were above the 0.5 PPM level. Water and sediment analyses for the above mentioned metal ions fell well within expected "normal" limits for unpolluted fresh water systems. No point sources could be identified for any of the metal ions. This is in contrast with results obtained on the lower Tennessee River by Hancock, et al, in which a large chemical complex was found to contribute significant quantities of trace metals. No significant seasonal variation of trace element content was observed in any of the sample types. Since the selenium content of all samples was so low, no laboratory bioaccumulation data were obtained. No general correlation between fish length and trace element content could be established, although there was a relationship for some elements, usually positive but sometimes negative. There was some correlation between trace element