In a cross-sectional Nong Han Lake study, lead in three aquatic species was below the 0.3 mg/kg limit and median estimated intake was 0.1004 µg/kg body weight/day. Although musculoskeletal symptoms were common, estimated dietary lead intake was not associated with symptoms after adjustment (aOR 1.30; p=0.450), so the symptoms should not be attributed to lead in aquatic foods.
Key findings
- All species were below 0.3 mg/kg. Median EDI was 0.1004 µg/kg/day (IQR 0.0645-0.1785). Musculoskeletal pain was 79.73% and joint/muscle pain 71.62%. Symptom reporting was associated with female sex (aOR 2.62), no lead-hazard training (3.39), more than 300 g per meal (2.47), and over 30 years of consumption (2.16), but not EDI (aOR 1.30; 95% CI 0.657-2.578; p=0.450).
Why this matters globally
Lake-dependent communities must balance food security with contaminant surveillance. Combining food measurements with consumption data is useful, but risk communication should avoid alarm when levels are below limits and symptom associations are absent.
Thai researcher contribution
Kasetsart University's Faculty of Public Health at the Chalermphrakiat Sakon Nakhon Province Campus collaborated with Chulalongkorn University's College of Public Health Sciences. Publisher data confirm no Sakon Nakhon Rajabhat University affiliation, correcting a place-name matching error.
Limitations to consider
Cross-sectional self-reported symptoms cannot establish causality. Blood or urinary lead was not measured, pain is nonspecific, dietary estimates depend on recall, and only three species were tested. Water, soil, occupational, and other exposure routes were not covered.