CANCER INCIDENCE, MORTALITY AND EXPOSURE-RESPONSE AMONG SWEDISH MAN-MADE VITREOUS FIBER PRODUCTION WORKERS

Objective The objective of this study was to provide an extended follo w-up of workers in three Swedish plants producing man-made vitreous fi bers (MMVF). Method Mortality and cancer incidence was investigated am ong 3539 male acid female workers, employed for at least one year befo re 1978. Mortality was followed from 1952 to 1990 and cancer incidence from 1958 to 1989. National and regional mortality and cancer inciden ce rates were used to calculate the expected numbers. Results Twenty-s even lung cancer deaths were observed compared with 23 expected (stand ardized mortality ratio 117, 95% confidence interval 81-176), based on regional mortality. With a latency time of 30 years, the lung cancer risk was significantly elevated, but no trend was found for the standa rdized mortality ratio with increasing duration of exposure to MMVF. T he lung cancer and stomach cancer mortality was higher in the rock woo l industry than in the fiber glass industry. Fiber exposure from 1938 to 1990 was estimated in the two rock wool plants by applying a model for historical fiber exposure estimation, specific for different job t itles in the rock wool production industry. No relationship was found between individually cumulated rock wool fiber exposure and lung cance r or stomach cancer risk. Conclusions The numbers of lung cancers and stomach cancer cases were low and did not therefore allow more general conclusions regarding the cancer hazard for exposed workers. A large European study in progress will probably allow more precise conclusion s.