Long-term bioaccumulation

CHRONIC TOXICITY TESTS LONG-TERM BIOACCUMULATION... 

Gunther, A.J., Davis, J.A., Hardin, D.D., Gold, J., Bell, D., Crick, J.R. et al. (1999) Long-term bioaccumulation monitoring with transplanted bivalves in the San Francisco Estuary, Mar. Pollu. Bull., 38, pp. 170-181. 

Upper LEVEL 1 Chronic toxicity Toxicity in soil and plants Additional mutagenicity Long-term toxicity Bioaccumulation Inherent biodegradability Additional abiotic degradability 100 t/annum or 500 t cumulative... 

There have been a nnmber of estimates of bioconcentration factors for total PCBs in aqnatic species following long-term exposure to PCB mixtures (EHC 140). Values for both invertebrates and hsh have been extremely variable, ranging from values below 1 to many thonsands. Bioaccnmnlation factors for birds and mammals for different Aroclors have indicated only limited degrees of bioaccumulation from food, for example, 6.6 and 14.8 for the whole carcasses of big brown bats Eptesicus fuscus) and white pelican (Pelecanus erythrorhynchos), respectively (see Environmental Health Criteria 140). 

Southworth GR, Peterson MJ, Ryon MG. 2000. Long-term increased bioaccumulation of mercury in largemouth bass follows reduction of waterborne selenium. Chemosphere 41 1101-1105. 

Calabrese, A., J.R. Maclnnes, D.A. Nelson, R. A. Greig, and P.P. Yevich. 1984. Effects of long-term exposure to silver or copper on growth, bioaccumulation and histopathology in the blue mussel Mytilus edulis. Mar. Environ. Res. 11 253-274. 

De Swart, R.L. et ah, Impaired immunity in harbour seals (Phoca vitulina) exposed to bioaccumulated environmental contaminants review of a long-term study, Environ. Health Perspect. 104 (suppl. 4), 823, 1996. 

Consider the following purely hypothetical example assessment for the exposure of an insectivorous bird to a new agricultural insecticide. This insecticide degrades very quickly after application, so that its toxicity dissipates after 24 hours. It does not bioaccumulate, and nonlethal doses are metabolized with no long-term consequences for the bird. These features imply a fairly simple assessment, involving the following expression for computing exposure of a bird to the insecticide within 1 day of its field application... 

There are critical needs with regard to protecting the environment (Medina, 1996). The use of solvents introduces stresses on ecosystems, ultimately on the global level. More testing for acute human toxicity is needed, but increasingly, researchers will strive to include effects on entire ecosystems, and long-term, multigenerational effects on fertility, reproductive quality, and hormonal functions. Any solvent that leads to environmental problems, that can be persistent, toxic, and bioaccumulative, or any combination of these three attributes, needs to be evaluated (Division, 1996). This... 

Due to their poor water solubility (less than 1 mg/L), disperse dyes have low acute ecological impact. Especially the acute toxicity to aquatic life is generally low. Nevertheless, according to the European chemicals legislation disperse dyes are classified as substances, that may cause long-term adverse effects in the aquatic environment [40,41], because they are not easily biodegradable and suspected of being potentially bioaccumulative due to their hydrophobicity. 

A striking aspect of lead in the body is its very rapid transport to bone and storage there. Lead tends to undergo bioaccumulation in bone throughout life, and about 90% of the body burden of lead is in bone after long-term exposure. The half-life of lead in human bones is estimated to be around 20 years. Some workers exposed to lead in an industrial setting have as much as 500 mg of lead in their bones. Of the soft tissues, the liver and kidney tend to have somewhat elevated lead levels. 

Indicates the rate at which a toxicant would be eliminated from the body affects its overall half-life Indicates for how long a compound would persist in the body and its potential for bioaccumulation, resulting in long-term adverse effects... 

Japan s Ministry of International Trade and Industry (MITI) was formed in 1949 and reorganized as the Ministry of Economy, Trade and Industry (METI) in 2001. METI is responsible for The Chemical Substances Control Law. It focuses on properties of chemical substances such as persistence, bioaccumulation, long-term toxicity to humans, and toxicity to plants and animals (hazards) and the likelihood of the chemical substance causing damage by remaining in the environment (risk).87 The law stipulates regulatory classifications and the measures to be taken for each classification. The classifications include the following ... 

The uncertainties identified in connection with these conclusions relate to the suitability of the current risk assessment approach for secondary poisoning, bioaccumulation, and whether or not debromination of the higher brominated molecules gives rise to other more toxic and bioaccumulative BDEs (such as Penta) is occurring at a significant rate in the environment. The risk assessors conclude that this combination of uncertainties raises concerns about the possibility of long-term environmental effects that cannot easily be predicted and that a strict PEC/PNEC approach may not be appropriate for this substance. 

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