Reproductive toxicity endogenous

The assessment of adverse health effects such as acute and chronic toxicity, carcinogenicity, reproductive toxicity, but also skin sensitization require in depth scientific knowledge of the processes in the human body that absorb, distribute, biotransform (or metabolize), or excrete the foreign chemicals but also endogenous compounds and the events associated with the toxicities in... 

Any reproductive toxicant capable of endocrine disruption can also be considered an endocrine-disrupting chemical (EDC) or an endocrine disrupter. Another term frequently used with respect to endocrine disruption, especially regarding xenobiotics that interact with endogenous hormone receptors, is hormonally active agent (HAA). In most instances, "EDC," "endocrine disrupter," or "HAA" can be used interchangeably to discuss the actions of a given xenobiotic (Evans, 2007). 

Exposure to estrogenic compounds through diet will differ for herbivores and carnivores, the latter being most likely to encounter endogenous steroids in their prey. Efficient uptake of steroids in mammals is illustrated by the use of the contraceptive pill, but routes of absorption in invertebrates remain to be determined. The relationship between endocrine disruption and metabolic toxicity, with reduced reproductive viability a secondary consequence of metabolic disturbance, also merits further study in invertebrate species. 

Dioxins and dioxin-like PCBs induce a broad spectrum of toxic responses, such as loss of body mass, hepatotox-icity, immunotoxicity, epidermal changes, embryotoxicity and carcinogenicity. In addition, they can act as endocrine disrupters, thereby mimicking or interfering with the action of endogenous hormones and other molecules of the endocrine system. Besides their interference with the reproductive system, there are indications of their role in thyroid hormone (TH) metabolism and function. The toxic and biological effects of these PHAHs depend on several factors, such as doses, route of administration, species, age, strain and sex of the animals (Safe, 1986). 

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