Volcanic mineral caused rare cancer in Turkey.

In two Turkish villages, nearly half of all deaths since 1980 have resulted from a form of cancer caused by inhaling erionite, a brittle and fibrous volcanic mineral found in construction materials used in the villages.

Millions of rural residents in central Turkey have probably been exposed to hazardous amounts of the mineral, say Y. Izzettin Baris of Guven Hospital in Ankara, Turkey, and Philippe Grandjean of the Harvard School of Public Health in Boston.

Erionite exposure can cause mesothelioma (SN: 9/3/83, p. 155), a rare cancer that develops in the membranes that line the chest and abdomen. Exposure to airborne asbestos can also cause the disease.

Baris and Grandjean studied 661 adults who, in 1979 or 1980, lived in one of two villages where erionite-rich rock is abundant and had been widely used in home construction. Another 230 adults in the study lived in a third village where erionite is rare.

Through 2003,117 people in the erionite-exposed villages had died of mesothelioma, making that cancer responsible for 45 percent of all deaths there during the study, the researchers report in the March 15 Journal of the National Cancer Institute. Just two villagers had died of mesothelioma in the unexposed village, and both of those people had been born elsewhere.

As evidence of erionite's dangers has emerged in recent decades, residents in the affected villages have abandoned contaminated structures.--B.H.