Occupational and environmental risks in and around a smelter in northern Sweden

Among the wives of 764 workers at a copper smelter in northern Sweden there were no significant differences between pregnancies before and after the husband's occupational exposure, with respect to the rate of congenital malformations. The rate of fetal deaths was significantly increased in pregnancies after the husband's exposure (exposed pregnancies). No such increase was found among the wives of office workers. When background variables like smoking habits and alcohol consumption of the parents were studied, the rates of stillbirths and induced abortion were found to be associated with paternal alcohol consumption. Since many different relationships were tested, these associations may, however, be fortuitous. The rate of induced abortion was low and showed no difference between exposed and non-exposed pregnancies. In a second questionnaire series comprising persons who did not respond to the first questionnaire, there was a significantly increased rate of induced abortion. This result indicates that the willingness to cooperate in questionnaire studies of pregnancy outcome may be associated with previous pregnancy experience. The results fit the hypothesis that the increased rate of fetal deaths may be caused by genetic damage through occupational exposure of the husbands. However, carry-home exposure to the wives remains a possible alternative explanation.