Exposure to Lead, Cadmium, Mercury and Arsenic Among Asian and Non-Asian Children and Adolescents in the United States: NHANES 2015-2018

Higher concentrations of heavy metals were reported mainly among adult Asian persons compared to other racial/ethnic groups in earlier NHANES cycles' studies. We aimed to examine concentrations of metals among Asian children/adolescents compared to children/adolescents identifying with other racial/ethnic groups, considering socio-demographic factors and potential mediation by fish/shellfish consumption. Using NHANES data (2015-2018), 5293 participants (1-19 years) with blood/urinary measurements of lead, cadmium, mercury and arsenic were included. Survey-weighted adjusted generalized linear models assessed differences in log-transformed metal concentrations between Asian and non-Asian participants, considering potential effect measure modification by parental education. Causal mediation effects of recent fish/shellfish consumption were estimated. Log-transformed metal concentrations were higher among Asian than among non-Asian children/adolescents. Lower parental education was associated with higher concentrations of cadmium and methylmercury among Asian participants, and effect measure modification was suggested. Proportions of the mercury exposure disparity mediated by recent fish/shellfish consumption were 9.1% (95% CI 2.6, 17.3%) for fish, and 5.7% (0.5, 12.0%) for shellfish, with similar findings for methylmercury. Overall, Asian identification was associated with higher toxic metal exposure, and among Asian children/adolescents those with parents with lower education were particularly affected. Dietary fish/shellfish intake explained a portion of the disparities. Prevention efforts should identify sources of elevated metal exposure focusing children and adolescents while considering diverse backgrounds and dietary habits including high fish consumption.