Environmental asbestos exposure and malignant pleural mesothelioma

Asbestos-related benign and malignant pleural diseases are endemic in some rural parts of central Turkey because of environmental exposure to asbestos fibres. We report here epidemiological data on 113 patients with diffuse malignant pleural mesothelioma (DMPM) diagnosed in our clinic in Eskişehir, located in central Turkey. Of the 113 patients, 59 were men and 54 women (male:female ratio = 1). Ninety-seven patients (86%) had non-occupational asbestos exposure; all were living in villages. Their mean age was 56 years. As the patients had been exposed to asbestos from birth, the latency period was equivalent to the age of the patients. Twenty-eight patients (29%) had lived in villages their entire lives. The other 69 (71%) had been born in a village but migrated to the city or had given up white-soil usage for various reasons. The mean exposure time was 55 years for those with a long exposure period and 25 years for those with a short exposure period, but there was no significant difference between the age of the disease appearance for both groups (55 and 56 years, respectively). Thus, the latency time of mesothelioma due to environmental exposure to asbestos was longer than that due to occupational exposure, but independent of the length of exposure. Soil samples from 67 villages were analysed, comprising a population of 10,120 villagers. Tremolite and some other types of asbestos were found. In conclusion, DMPM in our region is due to mainly to environmental exposure to asbestos. The risk is substantial as a large proportion of the villagers are exposed. After smoking, asbestos exposure is one of the most serious health hazards in our rural population.