Asbestos Exposure by Gender in Insulators and Construction Workers Gender of Insulators and Construction Workers Exposed to Asbestos

DISCUSSION

Our results confirm that occupational exposure to asbestos is associated with a very high risk of peritoneal cancer. Insulators showed the highest risk, and they contributed the most to the significant increase in risk in the construction industry. However, elevated risks were also observed for machine operators in both genders, in a few manufacturing industries, and among workers employed in services to dwellings and other buildings.

The test for trend was significant either by probability or by intensity of exposure to asbestos. Among women, risk was elevated in the publishing and printing industry, in retail stores, and in elementary and secondary schools. Trends by probability and intensity of exposure to asbestos were not significant.

As Selikoff pointed out (Selikoff, 1992a), the finding of new high-risk groups for asbestos-related diseases in studies based on death certificates should be explained with the tendency to list the most recent occupation in the death certificate, while prior or short-term asbestos work would not be expected to be recorded. This might account for most of the positive findings among women in the present study, such as elementary and secondary schools.

Our matrix classified teachers in the reference category, although asbestos was widely used for insulation purposes in schools. In fact, as explained in the Methods section, our unexposed reference group also included subjects with low probability and low intensity exposure.

However, cases of pleural mesothelioma among teachers have been discussed in relation to their asbestos exposure in school buildings [Lilienfeld, 1991; Anderson et al., 1991], and a history of prior employment in other occupations and industries with probable asbestos exposure was positive only for 3/12 teachers and 5/29 maintenance workers who died from mesothelioma in Wisconsin [Anderson et al., 1991].

It has been suggested that environmental, possibly residential, exposure to asbestos may account for the majority of female peritoneal mesotheliomas [Dawson et al., 1993]. Spouse exposure was reported as a risk factor for mesothelioma among women in England and Wales [Greenberg and Lloyd Davies, 1974].