The environment of the work place can be overtly dangerous if one must operate hazardous machinery, handle corrosive chemicals, or is exposed to toxic inhalants. Alternatively, occupational health hazards may be more subtle in the form of exposure to carcinogenic chemicals or irradiation, which may act insidiously during a period of many years. In addition to these well-recognized hazards of the work place, a new literature is emerging regarding the impact of occupational or other environmental exposure on the function of the endocrine system. These causal relationships may be particularly difficult to diagnose, since the disorders may be attributed to other well-described disease processes. Nevertheless, an increasing number of endocrine disorders are being recognized as attributable to occupational and nonoccupational environmental factors rather than hereditary or spontaneous disturbances.
With respect to the thyroid gland, textbooks about the endocrine system usually give colorful descriptions of the effects of dietary goitrogens, although