Chemical pollution and seafood safety, with a focus on mercury: The case of Pearl River Delta, South China

Most of the fish consumed in Hong Kong are farmed fish, including freshwater and marine fish, which are highly susceptible to various chemicals discharged from industrial sites nearby. It is recognized that emissions from coal-power plants are major sources of Hg in the environment worldwide. The situation is serious in the Pearl River Delta, South China, with a high demand of electricity, to support rapid development of various industries. In addition, the area has become the world's manufacturer for electrical/electric equipment, textiles, footwear, furniture, etc., emitting a wide range of toxic chemicals into the environment. In fact, “chemical food contaminants” is one of the 3 key global food safety concerns. Food safety is any action and policy which ensure food is safe, in the entire food chain, i.e. from production to consumption (WHO, 2013). This article attempts to review environmental health issues related to persistent toxic substances (PTS), with a focus on Hg; from biogeochemistry ecology epidemiology to policy and management, citing examples related to South China.