Exposure assessment and gender differences.

Exposure assessments for occupational epidemiological studies are typically conducted to (1) establish risk gradients with exposure, evaluating a potential causal relationship, or (2) estimate exposure-response dosimetry for quantitative risk calculations. Unavailable quantitative exposure data require use of surrogate or qualitative measures. Differences in women's employment patterns may make surrogate measures less reliable, resulting in systematic errors. Exposures associated with traditionally female careers have not been fully evaluated. Occupational cohorts are often defined to include workers with a minimum employment duration or employment for some minimum time in exposure-related jobs, thereby excluding many women workers. Even when included among studied and exposed worker cohorts, women's domestic exposures may confound risk evaluation. Male/female differences in xenobiotic uptake, distribution, kinetics, and metabolism may affect the relationship between external exposure and resulting biologically effective dose. Clinical factors alter the recognition of disease among women workers, confounding risk determination. Recognizing these problems during design and analysis of occupational cancer epidemiology research is essential to develop valid preventive strategies.