Risk of Dietary Mercury Exposure via Marine Fish Ingestion: Assessment Among Potential Mothers in Malaysia

Abstract

Mercury (Hg) is a very toxic heavy metal that can permanently damage the brain of a developing fetus, particularly through maternal fish consumption. Being the highest seafood consumers in South East Asia, Malaysian mothers are probably at Hg exposure risk. Hence, this study was undertaken to assess the health risk associated with Hg from marine fish consumption and the types of fish that could possibly increase the exposure dose. Assessment was done among potential mothers (n = 311) in the coastal rural and urban parts of Selangor, the most dense and developed state of Malaysia. Coastal rural women consumed significantly higher amounts of fish than their urban counterparts (164.0 vs. 111.7 g/day, p = 0.03) with Indian mackerel and torpedo scad being the most consumed species. These species also contributed to the highest average daily dose (ADD) of Hg. Consistent with the fish intake rate, coastal rural women were also clearly at higher risk of Hg exposure than their urban counterparts. The fish species that contributed to a significant Hg dose for both respondent groups was Indian mackerel. In addition, torpedo scad, yellow-banded scad, fourfinger threadfin, and golden snapper were the other species that significantly increased the exposure dose among coastal rural women, whereas for urban women, it was Indian scad, Japanese threadfin bream, and pale-edged stingray. Although the HQ calculated based on THg was lower than the unity HQ = 1.0, the identified species should be consumed with caution, especially by sensitive population groups.