A mortality study of Finnish pulp and paper workers

Mortality among workers in the Finnish pulp and paper industry was evaluated in a retrospective cohort study of 3520 workers who had been employed continuously for at least one year between 1945 and 1961. Six subcohorts were formed according to six work areas: sulphite, sulphate, paper, and board mills, maintenance department, and power plant. National mortality rates were used for comparison. The mortality of a cohort of 1290 sawmill workers was also studied in order to have a socially, geographically, and occupationally similar group without the exposures typical of the pulp and paper industry for comparison. Smoking habits were surveyed. Mortality was followed up until 31 December 1981. Overall mortality for the entire cohort did not differ from that expected (1044 obs, 1029.4 exp, SMR 101), but there was an excess of deaths from diseases of the circulatory system among the men (489 obs, 404.9 exp, SMR 121). This was due to the excess of deaths from ischaemic heart disease found among the men at the sulphite, sulphate, and paper mills, maintenance department, and power plant, but not at the sawmill. The existing smoking data did not explain this finding and it may therefore be associated with occupational exposures.