Quantitative risk–benefit analysis of fish consumption for women of child-bearing age in Hong Kong

Maternal fish consumption is associated with both risks from methylmercury (MeHg) and beneficial effects from omega-3 fatty acids to the developing foetal brain. This paper assessed the dietary exposure to MeHg of women of child-bearing age (20–49 years) in Hong Kong, and conducted risk–benefit analysis in terms of the effects in children’s intelligent quotient (IQ) based on local data and the quantitative method derived by the expert consultation of FAO/WHO. Results showed that average and high consumers consume 450 and 1500 g of fish (including seafood) per week, respectively. About 11% of women of child-bearing age had a dietary exposure to MeHg exceeding the PTWI of 1.6 µg kg–1 bw. In pregnant women MeHg intake may pose health risks to the developing foetuses. For average consumers, eating any of the 19 types of the most commonly consumed fish and seafood during pregnancy would result in 0.79–5.7 IQ points gain by their children. For high consumers, if they only ate tuna during pregnancy, it would cause 2.3 IQ points reduction in their children. The results indicated that for pregnant women the benefit outweighed the risk associated with eating fish if they consume different varieties of fish in moderation.