Background and aim

It is known that some of the chemical compounds in crude oil and gas can be carcinogenic. The Cancer Registry of Norway has several ongoing research projects that study the incidence and risk of cancer among offshore workers.

In 1989, the CRN received a request from the Norwegian Oil Industry Association (today Norwegian Oil and Gas). The Norwegian oil industry had grown significantly during the 1970s and 80s and the Norwegian Oil Industry Association was interested in an overview of cancer incidence and mortality among offshore workers. Following the request, CRN conducted a large survey in 1998 among 28,000 people who worked offshore between 1965 and 1998. Data from the survey resulted in the "Offshore-cohort", which has been the basis for several publications.

During the last decades, working environment and potential health hazards in the oil industry have received more attention. The Government has stated in reports to the Norwegian Parliament, that they want Norway to be a world leader in health safety and environment (HSE) standards in petroleum activities. As the industry is constantly developing, and with greater attention to HSE, there has been a need for exposure-related cancer studies from recent years, including data after 1998. Thus, with broad support from the industry, unions and regulators, the CRN started in 2019 to plan a new project. In this project, the plan is to use data from helicopter transport to offshore platforms, to identify individuals who have been offshore in the period from the 1980s until today. This cohort is called the "Heliport-cohort". The Heliport cohort will be a unique database that will provide an updated and almost complete overview of the employee group at offshore installations – and hence a high-quality monitoring tool for studies of benzene exposure and cancer risk from, and potentially other exposures and health outcomes, depending on formal authorization from regulatory agencies.

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  • Long-term rotating shift work can increase the risk of aggressive prostate cancer. Read more.
  • Increased risk for some cancer types among offshore workers compared to the remaining Norwegian population. Read more.
  • The risk of some types of lymphoma and leukaemia (acute myeloid leukaemia, multiple myeloma and chronic lymphocytic leukaemia) appears to increase as benzene exposure increases.
  • The risk of skin cancer appears to increase with duration of skin contact with benzene and crude oil. Read more here and here.

All publications from the Cancer Registry's offshore studies