Explaining differences in incidence rates of pleural mesothelioma between Sweden and the Netherlands.

In recent years in several countries a deceleration or leveling off of pleural mesothelioma rates has been observed. The impact of asbestos used was analysed by comparing a country with a relative modest incidence rate of mesothelioma (Sweden) and an early response to asbestos use with a country with one of the highest incidence rates of mesothelioma in Western Europe (The Netherlands). In Sweden the Cancer Register provided information on the annual incidence of pleural mesothelioma, whereas in The Netherlands mortality data were provided by Statistics Netherlands for the period 1969-2001. In The Netherlands among men the incidence rate was consistently higher (1.5-2 times) than in Sweden, whereas among women similar rates were observed. Assuming that none of the female cases was caused by occupational exposure to asbestos, minimum estimates of the etiologic fraction for occupational exposure to asbestos in men would be 82% in Sweden and 92% in The Netherlands. Possible explanations for the consistently higher incidence rates in the Netherlands than in Sweden include differences in exposure levels, the proportion of exposed subjects in the workforce and types of asbestos fibres used. Measures to decrease the exposure to asbestos seem to have decreased the risk of pleural mesothelioma in both countries among age groups below 60 years. This effect will result in a leveling off of the increase in pleural mesothelioma in both countries in the next decade.