Cancer mortality and sectors of employment: a cohort study in Italy

Cancer is a multifactorial disease. The large impact of occupational exposure on the burden of cancer continues to be a paramount public health concern that deserves more attention. The study aims to evaluate cancer-specific mortality risk in relation to sectors of employment.

We used a cohort from the Rome Longitudinal Study (ROL) and linked it with the National Social Insurance Agency (INPS) database to obtain working histories. We considered the longest duration of employment in a sector as a proxy of exposure, and insurance activities as the reference category. A Cox regression adjusted model was used to examine the associations between cancer-specific causes of death and the sector of employment in men and women. A similar analysis was performed considering the length of employment (≤ 10 years versus ≥ 10 years).

The study population comprised 910,559 (52% of the total population of the cohort after linkage with INPS) 30 + yr employees (53% men and 47% women) followed for a total period of approximately 7 million years. The outcomes confirmed some well-known associations (e.g. lung and pleura in construction, pleura in paper and printing, and lung in wood and leather) and suggested possible high-risk sectors that have not yet been thoroughly investigated. In men we observed an increased mortality risk for stomach cancer in the printing and paper industry (HR = 1.69, 95% CI:1.11-2.57) as well as for stomach and lung cancer in cleaning activities (HR = 1.98, 95% CI:1.13-3.49 and HR = 1.55, 95% CI:1.22-1.98, respectively). Among women, there was an elevated mortality risk in the cleaning industry for all malignant cancers (HR = 1.15, 95% CI:1.03-1.29), liver cancer (HR = 1.94, 95% CI:1.08-3.48) and cancer of the lympho-hematopoietic tissue (HR = 1.65, 95% CI:1.09-2.50).

The results showed an increased risk of cancer death in some traditional industrial sectors compared to the reference category of insurance activities such as construction and wood and leather products and limited evidence in sectors like cleaning, accommodation and food services and hairdressing. The adopted method proved to be effective in monitoring occupational risks and activating proper prevention initiatives and further insights.