Effect of occupational exposure to lead on new risk factors for cardiovascular diseases.

Objective: The cardiovascular effects of lead are caused primarily through an effect on blood pressure but are not just limited to an increased risk of hypertension. The aim of our study was to determine to what extent chronic exposure to lead affects new risk factors for cardiovascular disease (CVD) development, such as biomarkers of inflammation (C reactive protein (CRP) and fibrinogen) and biomarkers of endothelial dysfunction (homocysteine, asymmetric dimethylarginine (ADMA) and L-homoarginine).

Methods: A cross-sectional study was performed on a sample of 231 male volunteers, aged 20-60 years, working for at least 2 years in jobs with exposure to lead during the mining and processing of lead-zinc ores. The association between lead in blood and CVD biomarkers was evaluated using multiple linear regression, and the effects of exposure level were observed in workers divided into subgroups according to their blood lead concentration: <250, 250-400 and >400 µg/L.

Results: Lead in the blood correlated with new risk factors for CVD except for ADMA. Multiple regression analysis revealed that predictive properties for lead in the blood increased for particular biomarkers in the following order: L-homoarginine, fibrinogen, CRP and homocysteine. Among the specified groups, significant differences were observed only between the groups with the most and least exposure to lead, which differed in concentrations by 54.3% for CRP, 19.3% for fibrinogen, 10.6% for homocysteine and -25.5% for L-homoarginine.

Conclusions: These findings support the hypothesis that occupational exposure to lead can promote atherosclerosis, particularly in highly exposed individuals.