Cancer of the Lung and Nose in Nickel Workers

In 1949 the Minister of Pensions and National Insurance of Great Britain prescribed cancer of the lung and cancer of the nose as industrial diseases, when they occurred among certain classes of workers engaged in the refining of nickel. The published epidemiological evidence regarding the hazard is, however, scanty. It consists only of a series of case reports (Amor, 1939; Loken, 1950) and a statement of the total number of cases which occurred between 1923 and 1950 and were reported to the Ministry (Chief Inspector of Factories, 1952). The present investigation was, therefore, undertaken to obtain evidence relating to (1) the magnitude of the risk, and (2) the belief that the risk had been eliminated from the refinery concerned between 1920 and 1924. The data for the investigation were obtained from the records of death held by the medical officers of health of the districts in which the workers at the refinery lived. These records included copies of the death certificates of all persons dying in the districts and also of the certificates of persons resident in the districts, who had died elsewhere. Since the majority of the workers live in the Pontardawe Rural District of the County of Glamorganshire and a few others live in the County Borough of Swansea and in two other neighbouring districts, it was possible to obtain information about the causes of death of nearly all? if not of all? the workers who died during employment at the refinery and of a large proportion of the retired workers who had worked at the refinery when they had last been employed. These data can be compared with the national data for the different causes of death during the same period or with similar data for the same districts, but relating to men in other occupa tions. In the present study, it was thought better to use the other data from the same districts, when they were numerically adequate, as by this means it was possible to eliminate differences in the incidence of the two diseases due to non-industrial local factors. The Data Data for the 15,247 men over the age of 15 years who were resident in the four selected districts and who died in the period 1948-56 are shown in Table 1. The numbers of deaths are shown separately for three causes, five occupational groups, and 13 age groups. The causes have been classified as cancer of the lung, cancer of the nose, or " other causes " according to the diagnosis given on the death certificate. Where two or more causes were referred to the death has been classified to the underlying cause, in accordance with international usage? except in 10 instances in which a primary cancer of the lung was given as an associated disease, when the death was classified as if it had been attributable to the cancer. The numbers of cases in each occu pational and age group in which the international usage was varied are shown in Table 1. The five occupational groups consist of nickel, steel, and olliery workers, men employed in certain " other selected occupations ", and those in all other occupations. The men in " other selected occupa tions " were employed at an oil refinery or were described as aluminium, copper, spelter or " patent fuel " workers; they were studied separately because it was thought possible that one or other of these industries might also carry a specific risk of lung cancer.