Cadmium has toxic effects and due to its slow half-life accumulates in the body over an individual's lifetime. The amount of cadmium that is excreted in a person's urine can therefore be used as a biomarker of exposure. Exposure occurs through contaminated food or water or inhalation of tobacco smoke or polluted air. By use of a random population sample of 994 participants from north-east Belgium, Staessen and colleagues investigated prospectively whether environmental exposure to cadmium is associated with an increased risk of cancer, in particular lung cancer.
They recruited participants from an area close to 3 zinc smelters (high exposure) and compared them with a reference population that lived in a low exposure area. Cadmium in urine was measured from 1985-89 (baseline) and incidence of cancer in these individuals was measured until June 30, 2004.
At baseline, the average concentration of cadmium was 12.3 nmol/day for those from the high exposure area compared with 7.7 nmol/day for those from the low exposure area. During a median follow up of 17.2 years, 50 fatal cancers (including 18 lung cancers) and 20 non-fatal cancers (including 1 lung cancer) were identified. Overall cancer risk was significantly associated with a doubling of the excretion concentration of cadmium. This association remained after accounting for exposure to inorganic arsenic.
Dr Staessen states "Historical pollution from non-ferrous smelters continues to present a serious health hazard, necessitating targeted preventive measures".
Contact: Dr. Jan A Staessen, Study Coordinating Centre, Laboratory of Hypertension, Department of Cardiovascular Diseases, University of Leuven, Campus Gasthuisberg, Herestraat 49 bus 702, B-3000 Leuven, Belgium Tel. 321-634-7104, jan.staessen@med.kuleuven.be
Journal
The Lancet Oncology