Vibration on board and health effects

There is only limited knowledge of the exposure to vibrations of ships’ crews and their risk of vibration-induced health effects. Exposure to hand-arm vibrations from the use of vibrating tools at sea does not differ from that in the land-based trades. However, in contrast to most other work places, seafarers are also exposed to vibrations to the feet when standing on vibrating surfaces on board. Anecdotal reports have related the development of “white feet” to local exposure to vibration, e.g. in mining, but this connection has not been investigated in the maritime setting. As known from studies of the health consequences of whole body vibrations in land-transportation, such exposure at sea may affect ships’ passengers and crews. While the relation of back disorders to high levels of whole body vibration has been demonstrated among e.g. tractor drivers, there are no reported epidemiological evidence for such relation among seafarers except for fishermen, who, however, are also exposed to additional recognised physical risk factors at work. The assessment and reduction of vibrations by naval architects relates to technical implications of this impact for the ships’ construction, but has limited value for the estimation of health risks because they express the vibration intensity differently that it is done in a medical context

Exposures and health effects at sea: report on the NIVA course: Maritime Occupational Medicine, Exposures and Health Effects at Sea Elsinore, Denmark, May 2014

The presentations and discussions summarised provide an overview on the current state of knowledge on a wide range of occupational health risks to which seafarers are exposed. The definition of an occupational risk for a seafarer poses problems as their ship provides both their working and their living environment and, because of its mobility, can expose them to diverse climatic and infectious risks. Knowledge about levels of exposure to potential health risks in seafarers is limited when compared to those working ashore while, because of a pattern of working that is often temporary and insecure, there is little valid long-terminformation on ill-health that can be related to risks at sea and in port. The data that do exist mainly come from developed countries, especially those in North Western Europe and extrapolation from these populations to the Asian seafarers who now crew most ships is of uncertain validity.This course, run by the NIVA Foundation and supported financially by the Nordic Council of Ministers, provided a first opportunity to draw a wide range of information and experience together to review exposure and health risks in seafarers. As a result it provided both a forum for deciding on future needs for investigation and gave those attending a range of insights that can help inform their own practices

The metabolic syndrome among Danish seafarers

Background: Representing a cluster of risk factors related to insulin resistance, the metabolic syndrome (MS) is defined by a constellation of increased waist circumference in combination with dyslipidaemia, hyperglycaemia, and/or increased blood pressure. MS is a strong risk factor for a number of chronic diseases, including diabetes and cardiovascular conditions. Approximately 1/5 of Danish adults have MS, which has an etiological relation to nutritional factors, sleep patterns, work-related stress, fatigue, and physical activity — all of which are critical issues at sea.Materials and methods: Out of 655 Danish seafarers attending medical fitness examination by seafarers’doctors in 4 clinics, 524 participants (mean age of 38.5 years) underwent waist circumference measurements and provided questionnaire information about their workplace on board and their consumption of tobacco and alcohol. Blood samples were taken if waist circumference was increased. MS was defined according to the International Diabetes Federation as central obesity in combination with 2 out of the following conditions: elevated triglycerides, blood pressure, fasting plasma glucose, and reduced HDL-cholesterol (or treated hyperlipaemia or hypertension, or previously diagnosed type 2 diabetes, respectively).Results: The crude baseline prevalence of MS was 25.9% among male and 10.7% among female Danish seafarers. 30.6% were current smokers. The alcohol consumption was comparable to that of Danes ashore, but exceeded recommendations of 18.6%.Conclusions: MS was increased in this young group of seafarers. Seafarers with MS were advised to 10% weight-reduction, physical activity 1/2 hour/day, reduced intake of saturated fat and increased fibres indiet, smoking cessation, and control of alcohol consumption as an intervention measure. Follow-up will take place after 2 years