Health warning as pollutants build in delta fish

PUBLISHED : Tuesday, 04 October, 2011, 12:00am
UPDATED : Tuesday, 04 October, 2011, 12:00am


Oysters with 740 times the safe level of copper and 90 times the cadmium limit. Big-head croaker fish with 24 times the safe level of chromium. Lizardfish with 53 times the permitted lead level.

Much of the seafood from Guangdong waters is contaminated, tests show.

The figures come from Professor Huang Xiaoping, a researcher with the South China Sea Institute of Oceanology at the Chinese Academy of Sciences, who told the Yangcheng Evening News the Pearl River Delta was headed for ecological disaster unless more was done to curb industrial pollution.

The newspaper said waters around fisheries had high concentrations of heavy metals and other industrial pollutants. The ports with the worst marine environments were in Shenzhen, Zhuhai and Maoming.

Cheng Hing, general secretary of the Hong Kong Frozen Meat and Seafood Wholesalers and Retailers Association, said seafood from the mainland accounted for about a third of Hong Kong's total seafood consumption. Of those supplies, most come from the sea near Zhanjiang in Guangdong, and from Hainan province. 'It is a real concern, especially when we are talking about seafood cultivated near shorelines of the Pearl River Delta.'

The Guangdong Oceanic and Fisheries Administration reported that more than 40 per cent of waste water discharged into the sea last year was excessively polluted. It found that eight rivers flowing into the sea off Guangdong carried 1.08 million tonnes of pollutants, including petroleum, nutrients, heavy metals and arsenic. The area of polluted inshore seawater was 4,153 square kilometres.

Guo Pengran, a Guangdong-based expert on hazardous chemicals, said there had been abundant research showing that the water and sediment of the Pearl River Delta contained many heavy metal and organic pollutants.

'The pollutants will build up in marine animals,' Guo was quoted as saying by the Yangcheng Evening News. 'What's more serious is that the toxins are multiplied through the food chain and can eventually damage human health.'

The report said Guangdong's water pollution had not improved over the years because of the high cost of treating industrial waste water and because monitoring to deter plants from pumping toxins into the Pearl River was ineffective.

Commenting on Huang's findings, John Ho Wing-shing, associate professor of biochemistry at the Chinese University of Hong Kong, said: 'Even a high school science student can tell that this is way above acceptable levels when an oyster is found with copper 740 times above standards.'

Investigations were necessary to trace the source of pollutants and how they got into the water, Ho said. 'The mainland authorities have been catching up ... in regard to tackling environmental pollution, but chemical plants along rivers and the coast are taking advantage of grey areas.'