To investigate whether specific
cancers are associated with the occupation of butcher, as has been reported from other countries, a historical prospective cohort study was undertaken. The cohort consisted of all self employed butchers (n = 552) and pork butchers (n = 310) born since 1880 who set up a shop in the canton of Geneva from 1901 to 1969, and of their wives (n = 887). The study group was followed up from 1901 to 1990 for general mortality, from 1942 to 1990 for cause specific mortality, and from 1970 to 1989 for incidence of
cancer. There was no trace of 45 men (5%) and 52 women (6%). Compared with the general population of the canton of Geneva, butchers and pork butchers experienced a significant increase, taking into account 15 years of latency, in mortality from all causes (observed deaths (Obs) 540, expected deaths (Exp) 445.5, standardised mortality ratio (SMR) 121, 90% confidence interval (90% Cl) 113-130). There were significant excesses in incidence and mortality from
colorectal cancer,
cancer of the prostate, and all
malignant neoplasms, and in incidence of
cancer of the liver. The risk of
lung cancer was significantly increased among pork butchers (SMR 176, 90% Cl 114-262; standardised incidence ratio (SIR) 231, 90% Cl 137-368) but not among butchers (SMR 92, 90% Cl 59-138; SIR 113, 90% Cl 67-179). There was also a significant increase in mortality from
cancer of the larynx among butchers. For non-malignant causes of death significant excesses were found among all men for ischaemic
heart disease, motor vehicle accidents, and
cirrhosis of the liver. Analysis of subgroups showed a cluster of deaths from leukaemia among older butchers born between 1880 and 1899 (Obs 5, Exp 0.6, p < 0.0001). Exposure of pork butchers to
polycyclic aromatic hydrocarbons during meat smoking, which was assessed in a contemporary study, might have contributed to their increased risk of
lung cancer. The possible role of other factors, especially cigarette smoking,
nitrosamines, and oncogenic viruses was discussed. Moreover, there was evidence from another contemporary study that butchers and pork butchers ate more animal fat, and probably more animal
protein, than the average male population of Geneva. These results suggest that dietary factors could be implicated in the excesses of
colorectal cancer,
cancer of the prostate, and ischaemic
heart disease. An increased risk for
alcohol abuse might explain the excesses of
liver cirrhosis,
cancer of the liver,
cancer of the larynx and motor vehicle accidents. Among all wives overall mortality was similar to that expected (SMR 100, 90% Cl 93-108) and there was no significant excess risk for any specific
cancer nor for any non-malignant cause of death. Results for
cancer of the cervix uteri, especially among subgroups, suggest an increased risk consistent with previous findings from other countries.