To the Editor: We report elevated mercury levels in three infants, each the only child of Chinese parents living in Sydney. All three children had eaten fish congee (a rice and fish porridge) as a weaning food and ate fish regularly as toddlers. Their parents had sought medical advice for either developmental delay or neurological symptoms in the children.

A 2-year-old boy had demonstrated increasingly aggressive behaviour for the past 6 months. A general practitioner had diagnosed mercury poisoning in the boy’s father 2 months earlier, following investigation for complaints of allergies, rashes, abdominal pain and diarrhoea. The family ate fish (usually salmon, barramundi or snapper) at least five times a week, and had used unspecified herbal medicines in the past. The child had eaten fish regularly since weaning. The boy’s blood mercury level was 158 nmol/L (normal range [NR], < 50 nmol/L), a random urine mercury/creatinine (Hg/Cr) ratio was 9 nmol/mmol (NR, < 6 nmol/mmol*), and his hair mercury level was 1.42 mg% (NR, < 0.18 mg%). The boy’s father and mother (who was pregnant) also had elevated hair mercury levels, of 4.3 mg% and 6.0 mg%, respectively. The father and child were treated with chelation therapy elsewhere.