Objective: To assess exposure to mercury (Hg) among children in population subgroups whose traditional dietary practices include fish.
Study design: We determined blood Hg, red blood cell phosphatidylethanolamine omega-3 eicosapentaenoic acid as a marker of fish intake, and assessed indexes of childhood behavior in preschool children 1.5 to 5 years of age (n = 228) living in an ethnically diverse neighborhood in Vancouver, British Columbia, Canada.
Results: The median blood Hg was 4.6 nmol/L, range 0-67.9 nmol/L. Twelve (6%) children, all of whom were Chinese, had a blood Hg > 28.9 nmol/L. Blood Hg, total fish intake, and eicosapentaenoic acid were higher among Chinese than Caucasian children; however, higher fish intake did not predict blood Hg. Blood Hg was inversely associated with attentional focusing in children over 3 years of age after adjusting for confounding family variables, iron deficiency anemia, and zinc deficiency. Major sources of fish among Chinese children were imported fish rather than local fish.
Conclusion: Children from population subgroups within populations not considered at risk may be at increased risk of neurotoxicity caused by Hg exposure from fish.