Environmental geochemistry of Hg in intensive fish farming sites: implications of Hg speciation change related to its health perspectives

Abstract This paper presents an overview of research related to the role of fish farming on mercury (Hg) speciation and distribution in aquatic system. It critically reviews the major farm activities, e.g., organic waste loading, eutrophication and antibiotics using on the biogeochemical cycling of Hg. Hg is one of the most hazardous metals in the environment. The main exposure pathway of Hg to humans is through the consumption of fishery products. With the increasing consumption amount of fishery product, intensive fish farming activities increased dramatically and the production of aquaculture fish exceed the capture fish since 2013. However, intensive fish farming activities may change physical, chemical and biological characteristics of the benthic environment, which may have substantial influence on Hg speciation change and afterward bioaccumulation in fish through food chain. Thus, it is important to know how fish farming activities trigger Hg speciation change and distribution in the aquatic system, associated with the variation of Hg uptake by the aquaculture fish.