Organochlorines bioaccumulation

Fisk, A.T., R.J. Norstrom, C.D. Cymbalisty, and D.C.G. Muir. 1998. Dietary accumulation and depuration of hydrophobic organochlorines bioaccumulation parameters and their relationship with the octanol/water partition coefficient. Environ. Toxicol. Chem. 17 951-961. 

Aldrin/dieldrin Pesticide - organochlorine - bioaccumulates - used to control mosquitoes and termites Importation and manufacture prohibited in the US in 1987... 

Heptachlor epoxide Pesticide - organochlorine - bioaccumulates - heptachlor epoxide is a breakdown product of heptachlor, an insecticide from 1953 to 1974 in US on a wide range of insects. Most use canceled in 1974 and importation and manufacture prohibited in the US, use banned in 1988... 

Borga, K., Poltermann, M., Polder, A., Pavlova, O., Gulliksen, B., Gabrielsen, G.W. and Skaare, J.U. (2002) Influence of diet and sea ice drift on organochlorine bioaccumulation in Arctic ice-associated amphipods. Environmental Pollution, 117, 47-60. 

Many of the components of PCB and PBB mixtures are both lipophilic and stable, chemically and biochemically. Similar to the persistent organochlorine insecticides and their stable metabolites, they can undergo strong bioconcentration and bioaccumulation to reach relatively high concentrations in predators. 

Swackhamer, D.L. and R.A. Hites. 1988. Occurrence and bioaccumulation of organochlorine compounds in fishes from Siskiwit Lake, Isle Royale, Lake Superior. Environ. Sci. Technol. 22 543-548. 

Braune, B.M. and R.J. Norstrom. 1989. Dynamics of organochlorine compounds in herring gulls. III. Tissue distribution and bioaccumulation in Lake Ontario gulls. Environ. Toxicol. Chem. 8 957-968. 

Due to organochlorines dissolving in fats and oil, bioaccumulation in the food chain may occur. Figure 4 shows the simulation of the accumulation of a substance in fatty tissues under a regular intake. 

This model is the most fitting for the non-metabolized or very slow metabolized organochlorines like dioxin or DDT. We can see that this is an additional step in understanding the dioxin bioaccumulation in ecosystems. 

Another entry point for accumulation of organic in animal tissue and animal food products is direct ingestion of contaminated soil by grazing animals [44]. The compounds of main concern are the halogenated aromatics, including PCBs, organochlorine pesticides, PCDDs and PCDFs, which are resistant to metabolization and tend to accumulate in animal fat. The bioaccumulation factor (the ratio of the concentration of animal tissue or produce to the concentration in the diet) can be as high as 5-6 [43]. Compounds such as PAHs and phthalate esters are readily metabolised and excreted by the animals and thus do not accumulate in animal tissue or products. 

Several hundred-pesticide compounds of diverse chemical structures are widely used in the United States and Europe for agricultural and non-agricultural purposes (Fig. 10). Some are substitutes for organochlorines, which were banned due to their toxicity, persistence, and bioaccumulation in environmental matrices. According to a report published by the US-EPA, a total of 500,000 tons of pesticides was used in 1985 [144, 145, 148]. As far as specific pesticides are concerned, worldwide consumption of Malathion and Atrazine in 1980 amounted to 24,000 and 90,000 tons, respectively [149,150]. In the Mediterranean countries, 2100 tons of Malathion (active ingredient) were sprayed during the same period compared to 9700 tons in Asia [150]. 

Hargrave, B.T., Phillips, G.A., Vass. W.P.. Bruecker. P.. Welch. H.E.. and Siferd. T.D. Seasonality in bioaccumulation of organochlorines in lower tropic level arctic marine biota. Environ. Sci. Technol, 34(6) 980-987. 2000. 

Lindane (gamma-hexachlorocyclohexane) is one of the last of the old style organochlorine pesticides still in use. Use of organochlorines such as DDT, aldrin, dieldrin, heptachlor, and toxaphene is restricted or banned in many countries because of their persistence in the environment, bioaccumulation, and toxicity. Lindane was first isolated in 1825 along with other similar compounds, but its deadly effects on insects were not recognized until the 1940s. 

The organochlorine pesticides are considered persistent chemicals. Degradation is quite slow when compared with other pesticides, and bioaccumulation, particularly in aquatic ecosystems, is well documented. Their mobility in soil depends on the composition of the soil the presence of organic matter favors the adsorption of these chemicals onto the soil particles, whereas adsorption is poor in sandy soils. Once adsorbed, they do not readily desorb. These compounds induce significant abnormalities in the endocrine balance of sensitive animal and bird species, in addition to their adverse impact on humans, and their use is appropriately banned in most areas. 

Since diazinon is not a priority pollutant and has not been considered to pose serious threats from bioconcentration or bioaccumulation in fish and shellfish species, it has attracted far less attention in the United States than persistent organochlorines like DDT or chlordane in routine surface water monitoring networks. Carey and Kutz (1985) reported that the maximum diazinon residue collected in a national surface water monitoring program conducted from 1976 to 1980 was 2.38 ppb and that diazinon was detected in only 1.2% of the samples collected. More recently, Pereira and Hostettler (1993) conducted a study of the Mississippi River and its tributaries during 1991 and 1992. These authors reported that... 

Borga, K., Fisk, A.T., Hoekstra, P.F. and Muir, D.C.G. (2004) Biological and chemical factors of importance in the bioaccumulation and trophic transfer of persistent organochlorine contaminants in Arctic marine food webs. Environ Toxicol Chem, 23, 2367-2385. 

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