Metabolism bioaccumulation

Terrestrial fauna, such as birds, mammals, or domestic animals. Effects are heavy metals accumulation followed by possible disturbance of physiological and biochemical reactions and metabolisms. Bioaccumulation of Cd, Hg and Cu in the food web is the most important concern. 

Mathews, J.M., Gamer, C.E. Matthews, H.B. (1995) Metabolism, bioaccumulation, and incorporation of diethanolamine into phosphohpids. Chem. Res. Toxicol, 8, 625-633 Mathews, J.M., Gamer, C.E., Black, S.L. Matthews, H.B. (1997) Diethanolamine absorption, metabolism and disposition in rat and mouse following oral, intravenous and dermal administration. Xenobiotica, 27, 733-746... 

Little information on effects of DOSS on marine organisms are available [114-116]. A recently published paper deals with an intensive study of toxicity, bioaccumulation, metabolism, and elimination of DOSS in rainbow trout. The LCjq was determined to be 28 mg/L [116]. A very similar value was found for golden ide [117]. 

Food Chain Bioaccumulation. Endosulfan is bioconcentrated by aquatic organisms (Ernst 1977 Novak and Ahmad 1989 NRCC 1975 Roberts 1972 Schimmel et al. 1977) but not by plants or animals (ERA 1982a). The compound is metabolized by terrestrial (Coleman and Dolinger 1982 El Beit et al. 1981c Martens 1977 NRCC 1975) and aquatic organisms (Cotham and Bidleman 1989), and it does not biomagnify to any great extent in terrestrial or aquatic food chains (HSDB 1999). No additional information on the bioaccumulation of endosulfan is needed at this time. 

PAHs can be bioconcentrated or bioaccumulated by certain aquatic invertebrates low in the food chain that lack the capacity for effective biotransformation (Walker and Livingstone 1992). Mollusks and Daphnia spp. are examples of organisms that readily bioconcentrate PAH. On the other hand, fish and other aquatic vertebrates readily biotransform PAH so, biomagnification does not extend up the food chain as it does in the case of persistent polychlorinated compounds. As noted earlier, P450-based monooxygenases are not well represented in mollusks and many other aquatic invertebrates (see Chapter 4, Section 4.2) so, this observation is not surprising. Oxidation catalyzed by P450 is the principal (perhaps the only) effective mechanism of primary metabolism of PAH. 

Examples of differences in the responses of wildlife organisms to EDCs include the differences in sensitivity to phthalates and bisphenols among mollusks, crustaceans, and amphibians compared to fish. In invertebrates, biological effects are observed at exposures in the ng/L to low pg/L range, compared to high pg/L for most effects in fish (reviewed in Oehtmann et al. 2008). In addition, aquatic mollusks tend to bioconcentrate and bioaccumulate pollutants to a greater level than hsh, possibly owing to poorer capabilities for metabolic detoxification (see Chapter 4, Section 4.3). 

In general, it is easier to use models such as these to predict the distribution of chemicals (i.e., relationship between exposure and tissue concentration) than it is to predict their toxic action. The relationship between tissue concentration and toxicity is not straightforward for a diverse group of compounds, and depends on their mode of action. Even with distribution models, however, the picture can be complicated by species differences in metabolism, as in the case of models for bioconcentration and bioaccumulation (see Chapter 4). Rapid metabolism can lead to lower tissue concentrations than would be predicted from a simple model based on values. Thus, such models need to be used with caution when dealing with different species. 

Walker, C.H. (1990a). Persistent pollutants in fish-eating seabirds—bioaccumulation, metabolism and effects. Aquatic Toxicology 17, 293-324. 

Driscoll SK, AE McElroy (1996) Bioaccumulation and metabolism of benzo[a]pyrene in three species of polychaete worms. Environ Toxicol Chem 15 1401-1410. 

Devi, V.U. 1996. Bioaccumulation and metabolic effects of cadmium on marine fouling dressinid bivalve, Mytilopsis sallei (Rccluz). Arch. Environ. Contam. Toxicol. 31 47-53. 

Sublethal effects of mercury on birds, administered by a variety of routes, included adverse effects on growth, development, reproduction, blood and tissue chemistry, metabolism, and behavior. Histopathology and bioaccumulation were also noted. 

Landrum, P.F., B.J. Eadie, W.R. Faust, N.R. Morehead, and MJ. McCormick. 1984. Role of sediment in the bioaccumulation of benzo[a]pyrene by the amphipod, Pontoporeia hoyi. Pages 799-812 in M. Cooke and A.J. Dennis (eds.). Polynuclear Aromatic Hydrocarbons Mechanisms, Methods and Metabolism. Battelle Press, Columbus, OH. 

Most marine mammals are exposed to relatively high concentrations of those contaminants considered to be persistent (do not breakdown readily in the environment), bioaccumulative (are not readily metabolized and excreted by biota in aquatic food webs), and (immuno)toxic. Candidates in this category include various congeners of... 

Food Chain Bioaccumulation. Hexachloroethane in water may bioconcentrate in aquatic organisms to a moderate degree (Howard 1989), with a BCF of 139 reported in bluegills (EPA 1980a). Due to its rapid metabolism (Howard 1989) and the low incidence of hexachloroethane in ambient waters (Staples et al. 

Laskowski [1] has thoroughly reviewed the physico-chemical properties of the SPs, and these are summarized briefly below. SPs are typically of low water solubility (in the low microgram per liter range) and are highly nonpolar (logarithmic octanol water partition coefficients of around 6-7), indicating potential for bioaccumulation. Fish bioconcentration factors (BCF) of several hundred to several thousand are reported however metabolism limits the amount of bioaccumulation,... 

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