Cancer incidence in the Danish reinforced plastics industry

Increased occurrences of malignancies of the lymphatic and haematopoietic tissues have been reported from industries in which employees are potentially exposed to styrene. The aim of the study reported here was to describe cancer incidence in the reinforced plastics industry in Denmark. A total of 64,000 employees of 552 Danish companies assessed to have produced reinforced plastics at any time since the 1960s were identified from a public administrative registry of all Danish employers and wage earners. Cancer incidence in the population was compared with similar rates for the population at large. No excess risk for all neoplasms was observed. Among male employees, increased risks were found for cancer of the lung (396 cases; relative risk [RR], 1.15; 95% confidence interval, 1.04-1.27), of the pleura (20 cases; RR, 2.33; 1.42-3.60), of the nasal cavities (nine cases; RR, 1.55; 0.71-2.94), of non-Hodgkin's lymphoma (61 cases; RR, 1.27; 0.97-1.63) and for leukaemia (61 cases; RR, 1.15; 0.88-1.48). Among female employees, a reduced risk for non-Hodgkin's lymphoma was observed (one case; RR, 0.16; 0.00-0.88). Some support was thus found for previous reports of increased risk for respiratory cancers and for malignancies of the lymphatic and haematopoietic tissues. The results must be interpreted with caution, however, owing to shortcomings in the design of the study.