Endocrine disrupting chemicals thyroid

Potential Ejfects of Endocrine Disrupting Chemicals on Thyroid Eunction... 

Goldman JM, Laws SC, Balchak SK, Cooper RL, Kavlock RJ (2000) Endocrine-disrupting chemicals prepubertal exposures and effects on sexual maturation and thyroid activity in the female rat. A focus on the EDSTAC recommendations. Crit Rev Toxicol, 30 135-196. 

Takagi, H., K. Mitsumori, H. Onodera, M. Nasu, T. Tamura, K. Yasuhara, K. Takegawa, and M. Hrrose. 2002. Improvement of a two-stage carcinogenesis model to detect modifying effects of endocrine disrupting chemicals on thyroid carcinogenesis in rats. Cancer letters 178 1-9. 

Endocrine-Disrupting Chemicals, Fish, Medaka, Secondary Sexual Characters, Thyroid Hormones, Daphnids... 

Ammonium perchlorate (AP) has apphcations in munitions, primarily as an oxidizer for solid rocket and missile propellants. It is also used as an air-bag inflator in the automotive industry, in fireworks, and is a contaminant in agricultural fertilizers. Because of these uses and ammonium perchlorate s high solubility, chemical stability, and persistence, it has become distributed widely in surface and ground water systems. There is little information about the effects of perchlorate in these systems or on the aquatic life that inhabits them. However, it is known that perchlorate is an endocrine disrupting chemical that interferes with normal thyroid function and that thyroid dysfunction impacts both growth and development in vertebrates. Because perchlorate competes for iodine binding sites in the thyroid, the addition of iodine to culture water has been examined in order to determine if... 

McLachlan JA (2001) Environmental signaling what embryos and evolution teach us about endocrine disrupting chemicals. Endocr Rev 22(3) 319-341 Meeker JD, Calafat AM, Hauser R (2010a) Urinary bisphenol A concentrations in relation to serum thyroid and reproductive hormone levels in men from an infertility clinic. Environ Sd Technol 44(4) 1458-1463... 

Measurement of contaminants in fish has concentrated on muscle tissue since the aim has generally been to protect the health of the consumer rather than that of the fish. Endocrine tissue such as the gonads has been much more rarely examined, while data for adrenal, thyroid and pituitary levels are virtually non-existent. More data are available for the liver, as a lipid rich tissue and the major site of xenobiotic catabolism, but the concentrations have rarely been related to its capacity to produce vitellogenin or metabolise endogenous hormones. Tissue concentrations of a wide range of chemicals, are at a level which suggests that, either alone or in combination, they will cause significant endocrine disruption in fish in many polluted habitats. 

In recent years, concern that chemicals might inadvertently be disrupting the endocrine system of humans and wildlife has increased. The concerns regarding exposure to these endocrine disrupters are based on adverse effects observed in certain wildlife, fish, and ecosystems increased incidences of certain endocrine-related human diseases and adverse effects observed in laboratory animals exposed to certain chemicals. The main effects reported in both wildlife and humans concern reproductive and sexual development and function altered immune system, nervous system, and thyroid function and hormone-related cancers. Endocrine dismption is not considered a toxicological endpoint in its own right, but a functional change or toxicological mode(s) of action that may lead to adverse effects. Endocrine dismpters are addressed further in Section 4.11. 

Secondary to the societal concerns around chemical-related endocrine disruption, the OECD407 subacute 28-day toxicity study protocol has been updated in 2007 with parameters relating to endocrine homeostasis. Specifically, circulating thyroid hormones and detailed assessment of reproductive organ parameters were added to the protocol. Reproductive hormones were suggested as additional parameters but they were deemed not informative in view of their large variability in untreated animals. 

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