Occupational cadmium exposure and endocrine biomarker alterations in male workers: a cross-sectional study

Abstract

Occupational exposure to cadmium (Cd) remains an important environmental health concern, particularly in industrial settings where long-term exposure may affect multiple physiological systems. Although Cd has been linked to reproductive and cardiovascular toxicity, human studies that simultaneously evaluate biomarkers of endocrine and endothelial dysfunction remain limited. This cross-sectional study examined the association between occupational Cd exposure and hormonal and endothelial biomarkers in adult male workers. This cross-sectional study included 170 men, comprising 85 cadmium-exposed workers and 85 unexposed controls. Urinary cadmium concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS). Serum levels of total testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), arginine, and citrulline were measured using standard laboratory methods. Group comparisons and correlation analyses were conducted to assess associations between cadmium exposure and biomarker profiles. Cadmium-exposed workers had substantially higher urinary Cd concentrations than controls and higher ADMA and SDMA levels (both p < 0.001). In contrast, total testosterone, FSH, and the arginine/ADMA ratio were significantly lower in the exposed group, while LH showed a smaller but statistically significant reduction. Urinary Cd was inversely correlated with total testosterone and FSH, indicating that a higher internal cadmium burden was associated with less favorable endocrine biomarker profiles. Occupational cadmium exposure was associated with concurrent changes in endocrine and endothelial biomarkers among male workers. These findings suggest that combined assessment of endocrine and endothelial biomarkers may be useful for occupational monitoring of workers with chronic cadmium exposure.