Toxic endpoints in the study of human exposure to environmental chemicals

Human exposure to chemicals in the environment can occur in an acute or chronic manner causing toxicity to different organs or resulting in other adverse health effects. To assess if chemicals encountered by humans in different environments have the potential to be toxic, both in vitro and in vivo testing models can be utilized and will be discussed in this chapter. The structures and function of different organs of the body often predispose these organs to being especially sensitive to chemical exposures. Specificity, a general description of endpoints of toxic action will be discussed in relation to carcinogenesis, hepatotoxicity, renal toxicity, neurotoxicity, reproductive toxicity, endocrine toxicity, and immunotoxicity. Examples of environmental chemicals causing toxicity will be provided, and endpoints will be discussed ranging from histopathological characteristics to gene expression profiling.