Proportion of lung cancers in males, due to occupation, in different areas of the USA

Occupational data from 5 case‐control studies in the United States involving 2,973 male cases and 3,210 controls were analyzed to estimate the percentage of lung cancer attributable to well‐known and suspected lung carcinogens. The studies were conducted in areas heterogeneous in terms of industrial activities. The percentage of lung cancers attributable to occupations entailing potential exposure to well‐recognized carcinogens ranged, by study area, from 3 to 17%. The further inclusion of occupational groups with suspect carcinogenic exposures changed these estimates very little. Exclusion of data derived from next‐of‐kin interviews influenced the estimates of attributable risks, but not in a systematic fashion. The estimates also varied according to ethnic group, smoking status and birth cohort, with higher values in non‐whites, non‐smokers and among members of more recent birth cohorts. Possible errors in exposure classification, which may make these estimates conservative, are discussed.