Factors Influencing Blood Cadmium and Mercury Concentrations in Residents of Agro-Industries along Nam Phong River, Thailand

This cross-sectional analytical study aimed to determine the blood levels of cadmium (B-Cd) and mercury (B-Hg) and identify the factors influencing heavy metal accumulation in residents of Agro-Industries along the Nam Phong River. Quantitative data were collected, and systematic random sampling was used to obtain 420 samples for questionnaire interview and serum heavy metal testing for B-Cd and B-Hg. Multiple regression analysis was used to identify factors influencing the accumulation of heavy metals in the population and report mean differences, 95% confidence intervals and p-values. The results indicated that B-Cd levels were within the recommended safety limits for human health (5 µg/dL). However, 4.29% of respondents had Hg levels higher than the recommended safety limits for human health (10 µg/dL). Factors influencing Cd levels included sex (mean difference=0.13 µg/L, 95% CI: 0.03-0.24, p-value=0.02) and smoking (mean difference=0.14 µg/L, 95% CI: 0.09-0.19, p-value