Cumulative lead exposure in relation to mortality and lung cancer morbidity in a cohort of primary smelter workers

Scand J Work Environ Health. 1997 Feb;23(1):24-30. doi: 10.5271/sjweh.174.


Objectives: The purpose of this study was to determine the mortality and cancer incidence of long-term lead smelter workers at a primary smelter.

Methods: A cohort of 3979 workers employed for at least 1 year during 1928-1979 and a subcohort of 1992 workers employed in lead-exposed departments (lead only workers) was formed. The expected mortality in 1955-1987 and cancer incidence in 1958-1987 were calculated relative to the county rates, specified for cause, gender, 5-year age groups, and calendar year. A cumulative blood-lead index was used for the dose-response analyses.

Results: The lung cancer incidence of the total cohort [standardized incidence ratio (SIR) 2.8, 95% confidence interval (95% CI) 2.1-3.8] and the group with the highest exposure (SIR 3.1, 95% CI 2.0-4.6) was high. Similar risk estimates were observed with a latency of 15 years. The workers hired before 1950 had higher lung cancer risk estimates (SIR 3.6, 95% CI 2.6-5.0) than the workers hired later (SIR 1.3, 95% CI 0.6-2.6, no latency period). The risk estimates for lung cancer were further elevated in the subcohort of lead-only workers (SIR 5.1, 95% CI 2.0-10.5 in the highest exposed subgroup; latency period of 15 years). No excesses of other malignancies were noted.

Conclusions: The increased relative risks were probably mainly due to interactions between lead and other carcinogenic exposures, including arsenic. Further study is required concerning such possible interactions before a role in the induction of lung cancer can be ascribed to lead.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Cause of Death
  • Female
  • Follow-Up Studies
  • Humans
  • Incidence
  • Lead Poisoning / complications*
  • Lung Neoplasms / chemically induced*
  • Lung Neoplasms / mortality*
  • Male
  • Metallurgy*
  • Middle Aged
  • Occupational Diseases / chemically induced*
  • Occupational Diseases / mortality*
  • Occupational Exposure*
  • Risk Factors
  • Sweden