Bioconcentration environmental fate

Opperhuizen, A. (1986) Bioconcentration of hydrophobic chemicals in fish. In Aquatic Toxicology and Environmental Fate. Nineth Volume. ASTM STP 921. Poston, T.M., Purdy, R., Eds., pp. 304-315. American Society for Testing and Materials, Philadelphia. 

Endrin ketone may react with photochemically generated hydroxyl radicals in the atmosphere, with an estimated half-life of 1.5 days (SRC 1995a). Available estimated physical/chemical properties of endrin ketone indicate that this compound will not volatilize from water however, significant bioconcentration in aquatic organisms may occur. In soils and sediments, endrin ketone is predicted to be virtually immobile however, detection of endrin ketone in groundwater and leachate samples at some hazardous waste sites suggests limited mobility of endrin ketone in certain soils (HazDat 1996). No other information could be found in the available literature on the environmental fate of endrin ketone in water, sediment, or soil. 

Benzofuran is a colorless organic liquid with an aromatic odor. It is produced by the destructive distillation of coal, and may also be formed during processing of fossil fuels, such as coke production and coal gasification. Limited data indicate that 2,3-benzofuran may partition to soils and sediments from water, but the information available is insufficient to predict the environmental fate of this compound. Substantial bioconcentration in aquatic organisms is not expected based on the physical/chemical properties of 2,3-benzofuran. 

The ability to predict the behavior of a chemical substance in a biological or environmental system largely depends on knowledge of the physical-chemical properties and reactivity of that compound or closely related compounds. Chemical properties frequently used in environmental assessment include melting/boiling temperature, vapor pressure, various partition coefficients, water solubility, Henry s Law constant, sorption coefficient, bioconcentration factor, and diffusion properties. Reactivities by processes such as biodegradation, hydrolysis, photolysis, and oxidation/reduction are also critical determinants of environmental fate and such information may be needed for modeling. Unfortunately, measured values often are not available and, even if they are, the reported values may be inconsistent or of doubtful validity. In this situation it may be appropriate or even essential to use estimation methods. 

Food Chain Bioaccumulation. There is information that barium bioconcentrates in certain plants and aquatic organisms (Bowen 1966 Schroeder 1970). However, the extent to which plants bioconcentrate barium from soil or to which uptake occurs in terrestrial animals is not well characterized. Further studies on the bioconcentration of barium by plants and terrestrial animals and on the biomagnification of barium in terrestrial and aquatic food chains would be useful to better characterize the environmental fate of barium and define the importance of food chain accumulation as a source of human exposure. 

From their high n-octanol/water partition coefficient (K, ) (see Table 15) it can be assumed that PBDEs could be bio concentrated to a high extent in fish and other aquatic organisms. Recently the analysis, environmental fate, toxicokinetics, biotransformation, bio accumulation, toxicity, and environmental occurrence was reviewed by Pijnenburg et al. [249]. In the following part the bioconcentration of PBDEs in aquatic organisms, especially fish, is critically reviewed. Some information on endocrine disrupting properties of PBDEs is also presented. 

The evaluation of the results from the environmental fate leads to a predicted environmental concentration (PEC) of the pesticide representing the exposure level. The accumulation in the food chain of fish is expressed as BAF ( bioaccumulation factor in aquatic environment), that of mammals and birds as BCF (bioconcentration factor in terrestrial environment). Accumulation increases the exposure. The NOAEL (no observed adverse effect level) represents the hazard level. It is the result... 

The log -octanol-water partition coefficient (log Kow) is a measure of the lipophilicity of a substance. As such, log Kow is a key parameter in the assessment of environmental fate. Many distribution processes are driven by log Kow, e.g. sorption to soil and sediment and bioconcentration in organisms. 

The major environmental fate processes for butyraldehyde in water are biodegradation and volatilization. A number of biological screening studies have demonstrated that butyraldehyde is readily biodegradable. Volatilization half-lives of 9h and 4.1 days have been estimated for a model river (Im deep) and an environmental pond, respectively. Aquatic hydrolysis, adsorption to sediment, and bioconcentration are not expected to be important fate processes. 

Coumarin is readily biodegradable. Coumarin is unlikely to bind to soil. Coumarin does not bioaccumulate the bioconcentration factor has been determined to be <10-40. Various environmental fate studies have shown that coumarin in the environment would biodegrade and be lost to volatilization. Losses resulting from photolysis may also occur. 

Huckle, K.R. and P. Millbum. Metabolism, bioconcentration and toxicity of pesticides in fish. In Environmental Fate of Pesticides, edited by D.H. Hutson and T.R. Roberts, New York, Wiley, pp. 175—243, 1990. 

Hydrolysis is an important environmental fate process. Hydrolysis rate is characterized by a half-life of 17.5 and 11.9 days at pH 7 and 9, respectively. TOTM is not readily biodegradable. Bioconcentration factors are measured up to 2.7 which is considered low if released into surface water. TOTM is expected to absorb to suspended solids and the sediment. Because of the major use in electric wire and cable TOTM is fixed in the matrix and no substantial exposure is expected. 

In recent years the octanol/water partition coefficient has become a key parameter in studies of the environmental fate of organic chemicals. It has been found to be related to water solubility, soil/sediment adsorption coefficients, and bioconcentration factors for aquatic life. (Estimation of these three parameters solely on the basis of Kuw is described in Chapters 2, 4, and 5 respectively.) Because of its increasing use in the estimation of these other properties, Kow is considered a required property in studies of new or problematic chemicals. 

Lindane. This is the 7 isomer of hexachlorocyclohexane (HCH) and it is commonly used externally to prevent animals from infestation by lice and ticks and internally to discourage the propagation of parasites. Photodegradation is not a major environmental fate process. Bioconcentration is low, but present. Short-term exposure interferes with transmission of nerve impulses, while long-term exposure leads to liver and kidney damage. 

In recent years the octanol/water partition coefficient has become a key parameter in studies of the environmental fate of organic chemicals. It has been found to be related to water solubility, soil/sediment adsorption coefficients, and bioconcentration factors... 

Predicting the environmental fate and movement of plasticizers is currently hampered by a lack of information. There is also a lack of monitoring data to assess nonpoint sources. The aqueous solubility - a fundamental environmental property - of two of the 23 plasticizers has not been determined. As noted in this chapter, many properties such as Henry s Law constants, vapor pressure, organic carbon-water partition coefficients, octanol-water partition coefficients, bioconcentration factors, and photooxidation rates in the atmosphere were estimated using stractural analog models, empirical relationships based on other chemicals. Both biodegradation and adsorption appear to be the major mechanisms that control the fate of plasticizers released into the environment. Despite the... 

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