Endocrine disrupting chemicals compounds

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. ... 

From the wide variety of emerging pollutants of industrial origin that could be considered here, bisphenol A (BPA) and phthalate esters (PE) are of especial relevance not only because of the high volumes produced and their widespread use, but also because of their demonstrated toxicity, particularly as endocrine disrupters. Both of them have been included in the final report of the European Commission toward the establishment of a priority list of endocrine disrupter chemicals, EDCs [3], and have been rated as of high risk of exposure for human and wildlife populations. Because of their structural characteristics these compounds cannot be included in any of the groups described above, so they will be described in this section (see Fig. 10). 

Jjemba P.K. and B.K Robertson (2003). The Pate and Potential Impact of Pharmaceutical Compounds to Non-Target Organisms in the Environment. Proceedings of the Third International Conference on Pharmaceutical and Endocrine Disrupting Chemicals in Water. Minneapolis MN (3/19/2003). National Groundwater Association. NGWA Press, pp. 184-194. 

From these inventories and data, it is clear that society is facing an enormous problem of contamination. Many of the polluting compounds that are continuously dispersed are products of industrial activities such as phenols and halogenated phenols, polycyclic aromatic hydrocarbons (PAH s), endocrine disruptive chemicals (EDC), pesticides, dioxins, polychlorinated biphenyls (PCB s), industrial dyes, and other xenobiotics. In this chapter, we critically review the literature information on the enzymatic transformation of these polluting xenobiotics. This work is focused on peroxidases as enzymes able to transform a variety of pollutant compounds with the aim to reduce their toxicity and their environmental impact. 

One of the groups of suspect chemicals in the most active effluents in the survey was the alkyl phenols. However, there are probably several endocrine disrupting chemicals in the effluents and rivers, as different waste treatment plants may feed into the same river. As well as the alkyl phenols, a large number and variety of chemicals have been found to cause this effea, including organochlorine insecticides such as DDT, organotin compounds, phthalate esters, plant products, dioxins, polycyclic aromatic hydrocarbons, PCBs, and as expected natural and synthetic oestrogens. 

Bioaccumulation and Occurrence of Endocrine-Disrupting Chemicals (EDCs), Persistent Organic Pollutants (POPs), and Other Organic Compounds in Fish and Other Organisms Including Humans ... 

This phenomenon may be also important for all natural estrogens and endocrine-disrupting chemicals (EDCs) which are weak acids, such as 17 -estra-diol, estriol, ethynylestradiol, diethylstilbestrol, nonylphenol, octylphenol, bisphenol-A (BPA), tetrabromobisphenol-A (TBBA), hydroxy polychlorinated biphenyls, and other compounds with hydroxylated aromatic rings. 

Erb J, et al. (2001) Data from an estrogen receptor-based biosensor correlates with evidence of frog malformation and demonstrates a differential response of hERot and f to beneficial and harmful estrogenic compounds. In Proceedings of the 2nd International Conference on Pharmaceuticals and Endocrine Disrupting Chemicals in Water, pp. 203-217. Westerville, OH The National Ground Water Association. 

The allowable levels of air and water emissions of toxic chemicals should be reduced by at least one order of magnitude to account for the toxic effects of mixtures that remain largely unknown, but are increasingly being found to induce toxic effects at very low concentration levels. Endocrine disrupting chemicals and mixtures are examples of such compounds (Chapter 22). 

In summary, a large variety of methods have been deployed to predict ER binding of possible endocrine-disrupting chemicals. Consistently measured data for a large inventory of structurally diverse compounds are available [102,103] that will make extensive validation of the methods in future applications possible and also mandatory before helping regulatory bodies in the risk-assessment process. This validation should also include the prediction of affinities for compound classes that are not part of the training process. 

It is now known that endocrine disrupting chemicals are emitted from combustion sources. Interest has focused on the emissions of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F), which are also known carcinogens. However, oxy-PAH, epoxides, and other oxygenated species are known EDCs. These can also be emitted from combustion sources, although they are not well characterized. They are semipolar compounds that are difficult to analyze. Thus, improved methods of analysis are needed in conjunction with biological testing to determine the nature and quantity of EDC emissions from combustion sources. 

Volatile Organic Compounds in the 12 Endocrine Disrupting Chemicals... 

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