Kim · Annals of occupational and environmental medicine 2025 · cross-sectional study · n=825

Association of weight and dietary habits with high blood mercury levels in Korean adolescents: data from the KoNEHS cycle 4, 2018-2020.

Level 4 - case-series / case-control

Cross-sectional survey analysis

PubMed 39989115 · doi:10.35371/aoem.2025.37.e5 · record verified 2026-08-26

What was done

Data from the 4th Korean National Environmental Health Survey (KoNEHS 2018-2020) were analyzed for 825 middle and high school students aged 13-18 years who had blood mercury concentrations measured. Participants completed a survey on dietary and lifestyle habits. Associations of blood mercury levels with overweight status and seafood consumption were analyzed using a generalized linear model adjusting for covariates.

What was found

The geometric mean blood mercury level for the full sample was 1.37 µg/L, with 1.31 µg/L in normal-weight individuals and 1.43 µg/L in overweight individuals. In adjusted models, blood mercury levels were significantly associated with overweight status (estimate: 0.084; 95% CI: 0.015-0.153; p = 0.018), consuming large fish and tuna more than once a week (estimate: 0.18; 95% CI: 0.077-0.284; p = 0.001), and consuming fish once a week or more (estimate: 0.147; 95% CI: 0.043-0.250; p = 0.004). A stronger association was observed between large fish consumption and blood mercury in overweight adolescents.

Why it matters

The findings identify higher BMI and regular fish or tuna consumption as distinct factors linked to mercury exposure in adolescents, indicating a need for youth dietary guidance.

Limits

The cross-sectional design cannot establish causality. Dietary and lifestyle habits were survey-based and subject to recall bias. Findings from Korean adolescents aged 13-18 may not generalize to other regions or age groups. Portion sizes and non-dietary mercury exposure sources were not described in the abstract.