O-162 RISK OF CANCER AMONG OFFSHORE PETROLEUM WORKERS

Petroleum workers offshore have a potential for exposure to known and suspected carcinogens. We aimed to assess cancer incidence in a Norwegian register-based cohort of offshore workers. The cohort comprised 6600 men, aged 16-53, employed in offshore work in 1983, and was linked to the Cancer Registry of Norway for follow-up 1984–2020. Calendar period and age-standardised incidence ratios (SIRs) with 95% confidence intervals (CI) were estimated for all cancers combined and for 94 cancer sites using the general working population as the reference group. For all cancers combined, the study showed a SIR of 1.17 (95% CI: 1.11-1.23). Elevated risks were observed for cancer of the kidney (SIR: 1.35, 95% CI: 1.05-1.71), bladder (1.41, 1.14-1.74), larynx (1.92, 1.20-2.90), lung (1.26, 1.09-1.46), mesothelioma (1.90, 1.01-3.25) and oesophagus (all types (1.66, 1.13-2.36) and adenocarcinoma (1.80, 1.07-2.85)). However, no excess risk was observed for acute myeloid leukaemia (1.04, 0.47-1.97) or multiple myeloma (1.15, 0.78-1.63). Apart from the absence of excess risk of lymphohematological neoplasms and the novel finding of excess risk of kidney cancer, the findings corroborate existing research and underscore several cancer types for which offshore workers face increased risks. The available data did not allow for risk assessment of specific carcinogens or control of potential confounding factors such as lifestyle. In this register-based study, offshore workers active in 1983 had increased risk of certain cancers compared to the general working population. Further investigation into length of exposure, period of exposure and job type could yield further valuable insights.