Environmental and occupational medicine, 4th edition. Rom WN, Markowitz SB, eds. Philadelphia, PA: Lippincott Williams & Wilkins, 2006 Dec; :143-167
Reproductive and developmental toxicities of occupational and environmental exposures are potentially mediated by the complex interplay of toxicant activity, dosage, biologically effective dosage, and latency as well as by individual differences in maternal, paternal, and fetal metabolism, excretion, and storage. During the reproductive years, timing and dose of exposure relative to stage of ovulation, spermatogenesis, or pregnancy may influence the outcome(s). Further, potential vulnerability to toxicant effects varies throughout the life cycle, with some altering the maturation or future reproductive capacity during fetal or childhood development, and others acting on reproductive health or capacity during the reproductive years or beyond. For example, lead exposure has been implicated in delayed puberty among girls, sperm alterations among men, and congenital anomalies among children of exposed pregnant women (8,9). Identifying and interpreting risks requires consideration of the multiple factors. Thus, the primary purpose of this chapter is to outline reproductive health problems, together with some approaches for conducting and interpreting human studies of effects of occupational and environmental exposures on these problems, using current and historical research examples to convey the scope of study methods and factors that may affect study findings.