Heavy metals threatening Chinese white dolphins with extinction

Want China Times, Staff Reporter 2014-01-13

Marine biologists rescue a sick Chinese white dolphin in south China's
Pearl river estuary, one of its major habitats. (Photo/Xinhua)

Chinese white dolphins are once again under threat of extinction as research has found new toxins in the the marine mammals, with marine biologists at the Sun Yat-sen University (SYSU) in southern China's Guangdong province claiming that the species will drop by 74% in the next 60 years.

Research by the university has found organic pollutants and heavy metals, such as mercury and lead, in Chinese white dolphins, causing damage to their nervous system and immune system. The rare species are commonly found in the Pearl River Delta, south of China's east coast.

Wu Yu-ping, a professor at the SYSU's marine science department, said that the pollution of the Pearl River Delta is an increasing concern, and the density of heavy metals will no doubt jeopardize the future of the marine mammals.

The organic pollutants come from insecticide and fertilizers, which affect the dolphins' immune and reproduction systems, the professor said. Young dolphins absorb pesticides through their mothers while she nurses them, and the substances increase the young dolphins' mortality, or later, development, said Wu.

A fellow researcher at SYSU said it is vital for the authorities to improve the water quality in south China's Pearl river estuary to ensure the species' survival.