Endocrine disruptive chemicals

Issues in Environmental Science and Technology No. 12 Endocrine Disrupting Chemicals The Royal Society of Chemistry, 1999... 

Known and suspected endocrine disrupting chemicals needed to be ranked in order of priority for possible regulatory action. 

Table 2 Some known or suspected endocrine disrupting chemicals...

Culture a range of invertebrate species from the major phyla, preferably species with short life cycles. The effects of potential endocrine disrupting chemicals on growth rate, reproductive output, viability of offspring and sex ratio, and the vulnerability of different stages of the life cycle, can then be determined. 

Mechanistic studies to identify how endocrine disrupting chemicals interact with hormone systems are required. Although population effects coupled with biomarkers of exposure are strongly suggestive of endocrine disruption, the effect could be secondary to metabolic toxicity. Establishing mechanisms may avoid the need to make decisions on a weight of evidence approach alone. 

Potential Effects of Endocrine Disrupting Chemicals on Reproductive Eunction... 

There is some evidence for chemically mediated endocrine disruption in amphibians. The egg yolk protein, vitellogenin, is inducible in amphibians by exposure to DDT. " Males of the short clawed toad Xenopus laevis given 250 fig/g or 1 fig/g o,p -DDT for seven days have been shown to produce vitellogenin, although the induction was less than that achieved by treatment with 1 fig/g of either 17/1-oestradiol or diethylstilboestrol. Research has also shown that endocrine disrupting chemicals can alter sex ratios in wild populations of certain species PCB congeners and organochlorine compounds have been linked with male domination of sex ratios in polluted compared to unpolluted sites. ... 

Observed recovery in raptors has been slow owing to their lifecycle this is also an indication of the environmental movement and dispersal of endocrine disrupting chemicals from areas of intense agriculture to the aquatic environmental... 

NakadaN, Shinohara H, Murata A, Kiri K, Managaki S, Sato N, Takada H (2007) Removal of selected pharmaceuticals and personal care products (PPCPs) and endocrine-disrupting chemicals (EDCs) during sand filtration and ozonation at a municipal sewage treatment plant. Water Res 41 4373-4382... 

Collectively, the findings in experimental animals are insufficient to categorize methyl parathion as an endocrine-disrupting chemical. 

Recently, attention has focused on the potential hazardous effects of certain chemicals on the endocrine system because of the abihty of these chemicals to mimic or block endogenous hormones, or otherwise interfere with the normal function of the endocrine system. Chemicals with this type of activity are most commonly referred to as endocrine disruptors. Some scientists believe that chemicals with the ability to disrupt the endocrine system are a potential threat to the health of humans, aquatic animals, and wildlife. Others believe that endocrine disrupting chemicals do not pose a significant health risk, particularly in light of the fact that hormone mimics exist in the natural environment. Examples of natural hormone mimics are the isoflavinoid phytoestrogens (Adlercreutz 1995 Livingston 1978 Mayr et al. 1992). 

Dr. G. A. LeBlanc of North Carolina State University is evaluating effects of potentially endocrine-disrupting chemicals, including endosulfan, on steroid hormone biotransformation/elimination processes in daphnids, fish, and mice, and is constructing models of the processes. The work is being funded by the U.S. Department of Agriculture. 

Colborn T, Vom Saal FS, Soto AM. 1993. Developmental effects of endocrine-disrupting chemicals in wildlife and humans. Environ Health Perspect 101(5) 378-384. 

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