(May 26, 2009) Researchers in China say a commonly used paint chemical, triphenyltin (TPT), is leaking into the Yangtze River and may be the cause of deformities and dwindling populations of wild Chinese sturgeon. In a recent article published in the Proceedings of the National Academy of Sciences, the scientists found that a large proportion of juvenile sturgeon taken from the river had deformed skeletons or were missing eyes.

TPT is a common industrial and agricultural chemical, often used in paints and fishing nets. Farmers also employ the chemical as a fungicide to treat crops.

The Chinese Sturgeon, which has existed for more than 140 million years, was one of the first class of animals to be protected in China.

As part of the study, the scientists collected two- and three-day old Sturgeon from an area 24 miles downstream from the Three Gorges Dam. They then brought the fish to a laboratory in Jingzhou city in central Hubei province where 6.3 percent hatched with deformities and 1.2 percent were missing one or both eyes.

In the past scientists believed that a loss of habitat due to the construction of dams on the Yangtze was causing the sturgeon’s population to decline.

Wang Xihua, deputy director of the Ministry of Agriculture’s Bureau of Fisheries, said in 2005 that, “years of research show that it is river damming, rather than overfishing or industrial pollution, that causes the worst damage to fishery resources.” And a major international survey in 2004, the World Wide Fund for Nature said the Yangtze faces a greater environmental threat from dam building than any other river in the world, with 46 large dams already built, under construction or planned.

But the new study shows that pollution may have just as great an affect on sturgeon’s survival.

The sturgeon is not the only species threatened by dams and pollution on the Yangtze. For years, Probe International has warned that other forms of wildlife such as the Yangtze River dolphin, the finless porpoise, and the Yangtze alligator, would be endangered by the Three Gorges dam.

Brady Yauch, May 26, 2009

Further Reading:

Reuters story on the Chinese Sturgeon

Yangtze dams driving ‘panda of the water’ to extinction

Damming the Three Gorges: What Dam-Builders Don’t Want You To Know

New Yangtze dams spell disaster for fish

Yangtze Sturgeon (Acipenser dabryanus)