Nonylphenols endocrine disruptor

It was generally assumed that the endocrine disruptor nonylphenol (NP) is the most persistent metabolite of NPEO. However, experimental data on the formation of the metabolite NP from NPEO are surprisingly scarce, and mostly under anaerobic conditions NP has been reported to be formed [126,127]. Only one article reports a slight increase in NP concentration from the aerobic degradation of NPEO during the composting of wool scour effluent sludge [128]. 

Fig. 15.6 Aromatic ring cleavage degradation pathways of endocrine disruptor nonylphenol isomers by Sphingomonas sp. strain TTNP3. (Corvini et al. 2006)...

Depending upon the circumstance and desired effects, endocrine-disrupting chemicals can be either good or bad. The endocrine system is a finely balanced system responsible for fertility and many of the feminine and masculine traits we are all familiar with. Endocrine disruptors are used by millions of women in the form of the pill to control fertility. Chemicals in birth control pills subtly manipulate the endocrine system to reduce fertility. Unfortunately, we now know that many chemicals are capable of influencing the endocrine systems. When these chemicals, such as DDT and TCDD, are released into the environment, they reduce the fertility of wildlife. Exposure to endocrine disruptors is linked to decreased fertility in shellfish, fish, birds, and mammals. Endocrine disruptors such as nonylphenol have been shown to feminize male fish, interfering with reproduction. Some studies have also linked exposure to endocrine disruptors to decreases in human male sperm count. Ironically, urinary metabolites of the birth control pill as well as the female hormone estrogen pass through waste treatment plants and are released into the aquatic environment, where even small concentrations cause feminization of male fish. 

La Guardia MJ, Hale RC, Harvey E, et al. 2000. Endocrine disruptors (octylphenol, nonylphenol, nonyl phenol ethoxylates and polybrominated diphenyl ethers) in land applied sewage sludge biosolids. In Preprints of extended abstracts. American Chemical Society, Division of Envrionmental Chemistry. 

Recently, the hazardous effects of endocrine disruptors (environmental hormones) such as bisphenol A and nonylphenol on the human body have been reported, and led to the initiation of many studies concerning the detection and structural determination of these compounds present in tiny amounts [57]. As one of the QSAR analyses of environmental hormones, the relationship between their biological activity and chemical hardness has been reported [16]. By applying these analytical methods, the molecular toxicity and estrogen-like activity of environmental hormones have been found... 

Fig. 1. Estrogen and estrogen mimics. Many natural plant compounds (e.g. coumestrol) and synthetic chemicals (e.g. ethynylestradiol, diethylstilbestrol, 4-nonylphenol, o,p DDT, and kepone) act as endocrine disruptors by mimicking or blocking normal estrogen function via estrogen receptor dependent or independent mechanisms.

Endocrine disrupting compounds (EDCs) are particularly harmful often at very low doses (10 , 10 ° M), contradicting the assertion of Paracelsus regarding the importance of the dose in the effect of poisons. The problem moves from the fertilized cell to the embryo, the fetus, and eventually the very young child. Certain molecules, often of industrial origin, trick the hormonal system and lead to harmful effects. The following illustration compares the structures of estradiol and a nonylphenol, a fairly weak endocrine disruptor [29-34]. 

Contamination of the environment and agricultural products with endocrine disruptors(EDs) including dioxins, industrial chemicals and certain pesticide residues is a serious problem. These chemicals were found in the environment and agricultural products at nano-level concentrations, and are suspected of affecting ecosystems and human health. The Ministry of the Environment of Japan surveyed contamination of EDs in rivers, showing that bisphenol A, 176-estradiol and nonylphenol were detected in 50.3%, 40.4% and 31.0% of the water samples, respectively(Table 1). 

Lopez-Espinosa MJ, Freire C, Arrebola JP et al (2009) Nonylphenol and octylphenol in adipose tissue of women in Southern Spain. Chemosphere 76(6) 847-852 Loyo-Rosales JE, Rosales-Rivera GC, Lynch AM et al (2004) Migration of nonylphenol from plastic containers to water and a milk surrogate. J Agric Food Chem 52(7) 2016-2020 Masuo Y, Ishido M, Morita M et al (2004a) Effects of neonatal treatment with 6-hydroxydopamine and endocrine disruptors on motor activity and gene expression in rats. Neurai Plast ll(l-2) 59-76... 

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