Carcinoma of the pharynx and tonsils in an occupational cohort of asphalt workers.

ABSTRACT

BACKGROUND: We investigated a possible association between pharyngeal/tonsillar carcinoma and mixed carcinogen exposures in an asphalt roll company in Italy that used asbestos until 1979, when a new factory was built using a different production process. METHODS: We evaluated all workers involved in the entire production history of the company, divided into two subcohorts based on exposure status (workers in the original factory, 1964-1979, and those who worked only in the new factory, 1980-1997). We ascertained the vital status of the study population in February 2001. RESULTS: Among the subset of workers in the earlier subcohort, there were five deaths from pharyngeal/tonsillar carcinoma for a standardized mortality ratio of 21 (95% confidence interval = 8.8-51). No cases were recorded among workers hired after 1979. CONCLUSION: The increased standardized mortality ratio for this relatively rare cancer among workers exposed before 1979 may have been due to carcinogenic exposures at the plant.