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Noise, vibrations and ergonomic strain the top hazards for seafarers


Noise, whole-body vibrations from vessel hulls and ergonomic strain are the main problems in the work environment of present-day Swedish commercial shipping. This is evident from research in which work-environment factors, ill-health and cancer among seafarers were studied.

“The results are a good basis for improving the work environment in this sector,” says Karl Forsell, who has a PhD in occupational and environmental medicine from Sahlgrenska Academy, University of Gothenburg, and is a consultant physician at Norrland University Hospital.

His thesis, described as the first major survey of seafarers’ work environment in modern times, is based partly on a web-based questionnaire survey of nearly 2,000 seafarers from various shipping companies and types of vessel.

Noise and heavy loads

Noise proved to be common, and also to be associated with hearing impairment. Heavy loads on the neck, arms and back were especially common among staff involved in catering and on-board services, while engine-room workers complained more often of having to carry out work in uncomfortable working positions.

The safety environment received high ratings compared with land-based occupations, but ratings were relatively low among younger seafarers and seafarers who suffered from fatigue. This fatigue showed an association with stress and whole-body vibrations from the vessel hull. A high proportion of both men and women had experienced offensive actions or harassment.

The thesis also clarifies such known carcinogenic risk factors as asbestos and polyaromatic hydrocarbons (PAHs) involved in engine-room work.

High benzene levels

A field study of product and chemical tankers with a gasoline cargo showed that deck employees were exposed to particularly high benzene levels in certain work operations. Biomarkers indicated a biological uptake of benzene during a work session. They also showed a close agreement with the level of benzene exposure. Benzene is a known potential cause of acute myeloid leukemia (AML) and possibly other hematologic malignancies as well.

An epidemiological study showed that employment on tanker vessels before 1985 was more common among the seafarers who fell ill with hematologic malignancy. This applied to multiple myeloma in particular. These findings may mean that working on older tankers has caused an increase in the incidence of hematologic malignancy, probably due to occupational exposure to benzene. As for work on more modern tankers, no risk of hematologic malignancy was seen.

“Working conditions and health risks have been and are unique to seafarers in several respects, compared with people in land-based occupations,” Karl Forsell says. “The findings are also important for international shipping, in which occupational risks that have been remedied for us may persist in other countries.”

Title: Health hazards and cancer in relation to occupational exposures among Swedish seafarers

Contact: Karl Forsell

Images: Genre image (photo: Mattonstock) and portrait of Karl Forsell