Primary liver cancer death and occupation in Texas.

A death certificate case-control study of primary liver cancer and occupation was conducted to determine if the high risk of liver cancer in Mexican-Americans can be explained by farmworker exposures to pesticides. The association of liver cancer with the petroleum and chemical industry and with other potentially high-risk occupations was also examined. For the years 1969 to 1980, 1,742 deaths from primary liver cancer were identified for Texas males. Controls were randomly selected from other causes of deaths among males excluding all neoplasms, liver and gallbladder diseases, infectious hepatitis, and alcoholism, and were frequency matched to cases by age, race, ethnicity, and year of death. Risk for farmworkers based on age, race, and ethnicity-adjusted odds ratios (ORs) was not excessive (OR = 1.4, 95% confidence limits [C.L.] 0.8-2.2) but was larger than the risk for farmers (OR = 1.0, 95% C.L. 0.8-1.2). Excess risk in the petroleum and chemical manufacturing industries was confined to oil refinery workers (OR = 2.0, 95% C.L. 1.1-3.5). Other occupations with twofold risk or greater were plumbers and pipefitters (OR = 2.0, 95% C.L. 1.0-3.8), butchers and meat cutters (OR = 2.6, 95% C.L. 1.1-6.6), textile workers (OR = 3.1, 95% C.L. 1.2-7.8), cooks (OR = 2.2, 95% C.L. 1.1-4.5), and longshoremen (OR = 2.2, 95% C.L. 0.6-7.4).