Many modern work environments expose employees to the risk of injury from toxic substances. Attention to this risk may extend beyond the immediate concern for the worker's personal health, to concern that the worker's capacity to produce healthy offspring may be impaired. The conditions of employment in a particular workplace may require exposure to chemical agents that are toxic to the reproductive system of one sex and not of the other, toxic to the reproductive processes in both sexes, toxic to the developing fetus but not to the adult, or a combination of the above. Employers that exclude susceptible members of one sex from the workplace in order to prevent exposure to toxic agents, do so at the risk of violating federal employment discrimination law.