Respiratory cancer in Danish bakers: a 10 year cohort study.

A national cohort based on the census at 9 November 1970 and the death registration files from 1970 to 1980 was analysed to see if skilled Danish bakers had an excess of respiratory cancer. The group of skilled bakers was divided into occupational subgroups to try to narrow down the possible causes of cancer. Significant excess mortality was found among skilled bakers in retail bakeries, skilled bakers in hotels and restaurants, and independent bakers. To adjust for confounding factors, the SMR was calculated with control groups of equal social status and smoking habits. With all skilled workers as the reference group, skilled bakers in retail bakeries still had an excess, but now insignificant, risk but skilled bakers in hotels and restaurants had a significant excess risk. Compared with all self employed people in urban occupations in which an average of six or fewer workers were employed as a referent group, independent bakers had an insignificant excess risk. Suspected carcinogens in bakeries include polycyclic aromatic hydrocarbons (PAH), reaction products of PAH, free radicals, n-nitrosodimethylamine, aflatoxin, sterigmatocystin, and zeralenone.