Mercury and selenium content of Taiwanese seafood

Abstract

Fish consumption is avid in Taiwan (and other Asian nations), but little is known about the mercury and selenium content in local seafood. This paper reports on total mercury, methylmercury and selenium levels from 14 commonly consumed seafood items obtained from Taichung, Taiwan. Mean total mercury concentrations varied nearly 100-fold across species. Fifty per cent of the marlins sampled and 35% of the sharks exceeded the 0.3 µg g⁻¹ US Environmental Protection Agency (USEPA) guideline. Methylmercury comprised a majority of the total mercury in all species. In all species studied there was a molar excess of selenium over mercury. The rank order of mean selenium–mercury molar ratios was red tilapia (166.8) > abura (87.9) > river prawn (82.4) > whiteleg shrimp (64.2) > butterfish (44.6) > milkfish (37.0) > tuna (15.6) > grouper (13.9) > ayu (13.4) > coral hind (13.0) > weever (11.8) > saury (9.0) > shark (7.8) > marlin (4.2).

Keywords:

• fish
• mercury
• selenium
• risk–benefit
• selenium health benefit value

Acknowledgements

The authors thank Erica Boldenow, Ashley Maiuri, Stephen Zelda, Yi-Liang Huang, Jun-Han Huang and Chia-Kuan Liu for technical assistance. Funding for this study was received from the University of Michigan School of Public Health. No conflict of interest is declared.