Lung cancer risk and occupational exposure to meat and live animals

An increased risk of lung cancer has been reported for butchers and meat workers in several cohort studies, although confounding from tobacco smoking could not be ruled out in any of these studies. These exposures, as well as a potential risk associated with contact with live animals, are addressed here in a large case-control study with full adjustment for smoking. More than 5,900 subjects were included in a case-control study conducted in 7 European countries. For each job they employed local experts who assessed the exposure to a number of occupational agents, including (i) meat aerosols and (ii) live animals, on the basis of detailed occupational questionnaires. Information on tobacco consumption and other risk factors was also collected. A small increased risk of lung cancer was observed with exposure to meat aerosols, after adjusting for smoking, (odds ratio (OR) = 1.27, 95% confidence interval (CI): 0.92, 1.75), which was most apparent for the upper tertile of cumulative exposure (OR = 1.73, 95% CI: 1.03, 2.92). A similar overall effect was observed for exposure to live animals, with an increased risk observed for a high frequency of exposure, (OR = 1.69, 95% CI: 1.21, 2.36) and a high intensity of exposure, (OR = 1.85, 95% CI: 1.16, 2.94), with significant trends for increasing frequency (p = 0.012), intensity (p = 0.015) and cumulative exposure (p = 0.024). In conclusion, this study provides evidence for an association between exposure to meat aerosols and lung cancer apparent in the highest tertile of exposure. The authors identified a more consistent association with exposure to live animals.