Genetically and medically susceptible workers.

The likelihood of an individual becoming ill from a hazardous material or condition is strongly influenced by both their genetic makeup and their underlying state of health. Although the past decade has seen great advances in understanding human variation in health and genetic polymorphisms and in the diagnosis and treatment of disease, much less progress has been made in effectively using this information to protect worker health. Scientific evidence for increased susceptibility often is weak and rarely satisfies legal thresholds for sufficient risk to warrant exclusion from a particular job. When public safety is a major concern, many legally mandated exclusions are not well justified. Medical opinions about fitness to work should be based upon a systematic and credible analysis of the condition, its relationship to ability and risk for a particular job, and knowledge of possible accommodations. Conclusions should reflect the limitations of scientific knowledge and guidance from antidiscrimination legislation.