Showing papers on "Bioaccumulation published in 1977"

Toxic metals in surface waters from coal ash

Abstract: The concentrations of 10 (titanium (Ti), manganese (Mn), copper (Cu), chromium (CR), zinc (Zn), arsenic (As), selenium (Se), cobalt (Co), cadmium (Cd), and mercury (Hg)) toxic elements were measured in the water, benthic sediment, plants, invertebrates, and vertebrates of an ash basin and its drainage system at a coal-fired power plant of the Savannah River Project, Aiken, S.C., over a period of two years. During 12 months of this period the basin was essentially filled and little settling of ash occurred. In the remaining 12 months, dredging had been completed, adequate settling occurred and most of the effluent turbidity was removed. All elements were more concentrated in sediment and biota than in water, and five (Mn, Cu, As, Zn, and Se) were biomagnified by at least one biotic component as compared to concentration in benthic sediment. Plants had high accumulations of Ti, Mn, As, and Hg: invertebrates had high accumulations of Co, Hg, Cu, Cr, Cd, and As; and vertebrates greatly biomagnified Se and Zn. The streamlined biotic community of the system accomplished major removal of Mn, Zn, As, Se, and Cd from the effluent. The magnitude of bioaccumulation of Ti, Mn, Zn, As, Se, Cd, and Hg was increasedmore » during the period of adequate settling in the basin.« less

Heavy metals and related trace elements.

Abstract: A review is given of heavy metals and related trace elements in the aquatic environment. Other reviews and bibliographies are cited, dealing with the metabolism and transport of metal ions and with the toxic effects of stable and radioactive trace metals on aquatic organisms. The sources of trace elements in natural waters are discussed. It is suggested that atmospheric inputs of several trace metals comprise sizable fractions of total inputs to the Great Lakes and continental shelf waters. Information on stack emissions of trace elements from a coal-fired steam plant was used to estimate the likely range of air concentrations and inputs to a forested watershed in Tennessee. Some basic concepts of cycling of elements through aquatic communities were examined, such as the Pb, Mn and Zn concentrations in sediment and estuarine plants and animals colonizing dredge-spoil disposal areas. The use of plants as biological indicators of trace element contamination was outlined, as well as bioaccumulation in aquatic fauna. The effects of environmental factors on the kinetics of element exchange were noted, for example the influx rates of Cs 137 in tubificid worms, and Co 60 and Zn 65 in shrimp were shown to be temperature dependent. The toxicity ofmore » heavy metals on aquatic fauna was discussed, such as the histopathological lesions in the kidney and liver of fishes caused by heavy metals, and the effects of Hg and Cu on the olfactory response of rainbow trout.« less

Influence of Lipid Pool Size on Bioaccumulation of the Insecticide Chlordane by Northern Redhorse Suckers (Moxostoma macrolepidotum)

Abstract: An effect of the lipid pool size on the accumulation and clearance of cis- and trans-chlordane by northern redhorse suckers (Moxostoma macrolepidotum) has been demonstrated. A technique was developed using 203Hg-labeled methylmercury as a tracer, which permits the direct determination of the assimilation efficiency from food and the biological half-life of chlorinated hydrocarbons in terms of individual fish. Tissue retention of the insecticide chlordane in fish was directly proportional to the adiposity of the fish. For a fish containing 2% lipid, the half-life of the cis-isomer was 60 days and for the trans-isomer, 33 days. The net assimilation efficiency from food to fish tissue was also influenced by adiposity. These results on uptake and clearance, when used in a simple model for pollutant bioaccumulation, indicate that the steady state concentration of chlordane in fish will not exceed the concentration of chlordane in the diet unless the adiposity of the fish is high.

Absorption, Accumulation, and Elimination of Pesticides by Aquatic Organisms

Abstract: Absorption, accumulation and elimination of pesticidal compounds were studied by using equilibrium type model ecosystems. Various factors such as the amount of pesticides, size of ecosystem, temperature, physical chemical characteristics of the pesticides, etc. were studied in relation to the rate of pesticide pick up by test organisms. The design of the model is important inasmuch as it greatly influences the outcome of pesticide accumulation studies. The pattern of bioaccumulation of pesticides is compound specific, and it appears to be possible to select certain chemicals as “benchmarks” (e.g. DDT) to arrive at relative figures for potencies for bioaccumulation. In the case of complex model ecosystems involving several biological materials, the levels of pesticides in each organism are determined by “competition” among groups of biomass for available pesticides, in addition to the “foodchain” accumulation. The rate of desorption (elimination) of pesticides appears to be species-specific. The final level of pesticides in any given species is determined by these two opposing processes: i.e. absorption and elimination reactions.

Nationwide residues of mercury, lead, cadmium, arsenic, and selenium in starlings, 1973.

Abstract: Research report:Bioaccumulation in starlings of various toxic elements registered at noticeable levels during 1972 for 51 sites sampled. There was, however, a significant overall decline in mercury and lead arsenic residues since previous samples were taken in 1971. Arsenic levels, on the other hand, increased, and lead residues were significantly higher in starlings from urban areas. (1 map, 10 references, 3 tables)

Dynamics of Pesticides in Aquatic Environments

Abstract: The water solubility, adsorption, and bioaccumulation of pesticides and related chemicals have been discussed in the light of dynamics of pesticides in the aquatic environments. The solubility of chlorinated biphenyl analogs increased with a decreasing number of chlorine atoms in the molecule. In contrast, adsorption of polychlorinated biphenyls on clay, sand, soils, and humic acid increased as the number of chlorine atoms increased. The octanol/water partition coefficient of organophosphate pesticides varies over a wide, range. Ethoxy groups usually increase the partition coefficient, as compared with the corresponding methoxy analogue. The bioaccumulation of various pesticides in fish was influenced by polarity and water solubility. There is a qualitative correlation between water solubility and fish bioaccumulation--the bioaccumulation decreased as the solubility of the pesticide increased. Water solubility is important in decreasing the dynamics of pesticides in aquatic environment.

Behavior of mercury in biosystems. I. Uptake and concentration in food-chain.

Abstract: The study was conducted to measure both the rate of uptake of two mercurial compounds in a simple model food-chain consisting of three trophic levels (bacteria, larvae and fish) and to ascertain the Hg/sup 2 +/-concentration factor in each. These three organisms represent a unique food-chain system that can be reared easily under controlled laboratory conditions. They are also able to establish themselves within a short period of time independently of the presence or absence of a very low concentration of radioactive mercury in either the organic or inorganic form. Factors affecting both bioaccumulation and concentration factor (CF) were also examined.

Availability of Sediment-Adsorbed Selected Pesticides to Benthos with Particular Emphasis on Deposit-Feeding Infauna.

Abstract: : The primary objective was to determine the availability of sediment-associated chlorinated hydrocarbon pesticides to deposit-feeding infauna. This was to include determination of uptake from interstitial water, mineral particulates, and organic detritus, as well as an estimate of the degree of bioaccumulation. Results of the study demonstrated that a small fraction of freshly added radiolabeled pesticide was available for uptake by benthic organisms.