New research has revealed a higher risk for mesothelioma in seafarers and fisherman in Nordic countries. A seafarer is someone who makes their living at sea.
The study conducted by the Danish Cancer Society found an elevated risk in most types of cancer among Nordic seafarers. Mesothelioma was one of just three cancers whose cause was not difficult to guess.
The research included tens of thousands of seamen and fisherman and spanned more than 40 years. The authors say malignant mesothelioma in seafarers is the result of on-the-job asbestos exposure.
Asbestos at Sea
Asbestos is a toxic mineral. It causes malignant mesothelioma and several other types of cancer. Before scientists made the connection between asbestos and cancer, it was a popular insulator and building component around the world. Asbestos is strong, cheap, and resistant to heat and fire.
One place where asbestos was used heavily was in shipbuilding. People who live or work on ships are in danger of inhaling or swallowing microscopic asbestos fibers. These fibers become embedded in the tissue, raising the risk for mesothelioma and other cancers.
Previous studies have found higher rates of mesothelioma among shipbuilders, shipbreakers and sailors. The new study found that the risk for mesothelioma in seafarers and fishermen in five Nordic countries is also higher than it is for other people. The culprit is almost certainly the asbestos on their ships.
“While the majority of cancers could not be linked to specific occupational factors, increases in mesothelioma, lip and non-melanoma-skin cancer indicate previous exposure to asbestos, ultraviolet radiation and potentially also chemicals with dermal carcinogenic properties at sea,” states the report.
The new study tracked cases of mesothelioma in seafarers and fishermen between 1961 and 2005. It included 81,740 male seafarers and 66,926 male fishermen. The researchers used cancer data from Denmark, Finland, Iceland, Norway and Sweden to determine cancer rates in the general public.
Mesothelioma in Seafarers and Shipbuilders
Any job that requires workers to work around asbestos carries the risk for mesothelioma. Many past studies have highlighted the danger inherent in working on ships.
But the news about mesothelioma in seafarers and other ship workers is not all bad. In late 2019, the UK learned that it’s high rates of asbestos cancer in shipbuilders was finally declining.
Shipbuilding was once a major industry in the UK just as fishing is a major industry in Nordic countries. But the National Heart and Lung Institute at Imperial College London says the number of mesothelioma deaths in districts with shipyards has gone down.
Most new ships are built without asbestos. But workers who dismantle decommissioned ships (called shipbreaking) still face a higher mesothelioma risk.
Ugelvig Petersen, K, et al, “Cancer incidence among seafarers and fishermen in the Nordic countries”, January 9, 2020, Scandanavia Journal of Work, Environment, and Health, Epub ahead of print, https://www.sjweh.fi/show_abstract.php?abstract_id=3879
Reynolds, CJ, et al “Mesothelioma mortality in Great Britain: how much longer will dockyards dominate?”, October 29, 2019, Occupational and Environmental Medicine, https://oem.bmj.com/content/76/12/908