Cancer mortality in mercury miners

• Published in: Gaceta sanitaria Vol. 21; no. 3; p. 210
• Main Authors: Gómez, Montserrat García, Boffetta, Paolo, Klink, José Diego Caballero, Español, Santiago, Quintana, Javier Gómez, Colin, Didier
• Format: Journal Article
• Language: English; Spanish
• Published: Spain 01-05-2007
• Subjects: Cause of Death; Central Nervous System Neoplasms - epidemiology; Central Nervous System Neoplasms - mortality; Cohort Studies; Colonic Neoplasms - epidemiology; Colonic Neoplasms - mortality; Confidence Intervals; Female; Follow-Up Studies; Humans; Kidney Neoplasms - epidemiology; Kidney Neoplasms - mortality; Liver Neoplasms - epidemiology; Liver Neoplasms - mortality; Lung Neoplasms - epidemiology; Lung Neoplasms - mortality; Male; Mercury - adverse effects; Mining; Neoplasms - epidemiology; Neoplasms - mortality; Occupational Exposure - adverse effects; Poisson Distribution; Risk Factors; Spain - epidemiology; Time Factors; Urinary Bladder Neoplasms - epidemiology; Urinary Bladder Neoplasms - mortality; Spain
• ISSN: 0213-9111
• DOI: 10.1157/13106803

To analyze cancer mortality in a cohort of mercury miners.
Cancer mortality in 3,998 workers exposed to mercury in Minas de Almadén y Arrayanes S.A. was studied. The follow-up period was from 1895 to 1994. Vital status and the basic cause of death, in the case of fatalities, were determined. Standardized mortality ratios (SMR) by age, sex and calendar period were calculated. Expected deaths were obtained from age, sex and calendar period specific rates for the Spanish population.
The vital status of 92% of the workers could be assessed. At the end of the follow-up period, 1,786 workers were alive in 1994 (49%), 1,535 were dead (42%) and the status of 327 could not be determined (8%). Cancer mortality was significantly lower than expected, with an SMR of 0.72 (95% confidence interval, 0.63-0.82), mainly due to lower than expected mortality from colon and bladder cancer. Deaths from liver cancer were slightly higher than expected (20 deaths vs. 17 expected). Deaths from lung and central nervous system cancers were as expected, while mortality from kidney cancer was lower than expected. A positive trend in mortality from all types of cancer was observed, associated with exposure duration.
This study provides additional evidence of the absence of an increased risk of cancer in workers exposed to inorganic mercury.