Vol.:(0123456789) 1 3 Exposure and Health https://doi.org/10.1007/s12403-017-0270-x ORIGINAL PAPER Risk of Dietary Mercury Exposure via Marine Fish Ingestion: Assessment Among Potential Mothers in Malaysia Pravina Jeevanaraj 1,2  · Zailina Hashim 2  · Saliza Mohd Elias 2  · Ahmad Zaharin Aris 3 Received: 14 July 2017 / Revised: 2 December 2017 / Accepted: 20 December 2017 © Springer Science+Business Media B.V., part of Springer Nature 2018 Abstract Mercury (Hg) is a very toxic heavy metal that can permanently damage the brain of a developing fetus, particularly through maternal fsh 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 fsh consump- tion and the types of fsh 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 signifcantly higher amounts of fsh 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 fsh intake rate, coastal rural women were also clearly at higher risk of Hg exposure than their urban counterparts. The fsh species that contributed to a signifcant Hg dose for both respondent groups was Indian mackerel. In addition, torpedo scad, yellow-banded scad, fourfnger threadfn, and golden snapper were the other species that signifcantly increased the exposure dose among coastal rural women, whereas for urban women, it was Indian scad, Japanese threadfn bream, and pale-edged stingray. Although the HQ calculated based on THg was lower than the unity HQ = 1.0, the identifed species should be consumed with caution, especially by sensitive population groups. Keywords Mercury · Marine fsh · Health risk · Hazard quotient Introduction Mercury (Hg) is considered to be a very toxic metal found in water bodies and of serious concern due to its persis- tence and bio-accumulative nature. Non-occupational Hg exposure to humans occurs mainly through the ingestion route, and fsh consumption is a major pathway. Elemental (Hg 0 ) and inorganic Hg (IHg) from industrial and urbani- zation activities settle onto the sediment and the aquatic environment where it is microbiologically transformed into methylmercury (MeHg) through a process called methyla- tion (Zahir et al. 2005). Both the IHg and MeHg are taken up by phytoplankton and then assimilated and retained across the food chain from small animals (usually zooplankton), to small fsh that feed on zooplankton followed by larger fsh that feed on small fsh. Being at the top of food chain, fsh thus concentrate larger amounts of Hg, which is then fnally assimilated by humans at the highest concentration upon consumption (Abdel-Baki et al. 2011; Bastos et al. 2016; Liu et al. 2014). Fish is the main protein source in the Asian diet, par- ticularly among Malaysians, who are the highest seafood consumers in Southeast Asia. This is in agreement with the increase in the fsh consumption pattern of Malaysians (Tan and Lee 2005; Teh 2012), as well as the protein intake whereby fsh constitutes 60–70% of the national animal pro- tein intake, with a per capita consumption of 47.8 kg per year (Bako et al. 2013). Furthermore, the Malaysian Adult Nutrition Survey (MANS) found that 51.3% of the rural population and 33.6% of the urban population consume * Zailina Hashim zailina@upm.edu.my 1 Department of Diagnostic and Allied Health Science, Faculty of Health and Life Sciences, Management and Science University, Shah Alam, Malaysia 2 Department of Environmental and Occupational Health, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Malaysia 3 Department of Environmental Science, Faculty of Environmental Studies, Universiti Putra Malaysia, Serdang, Malaysia