Thousands of fish found dead near site of Tianjin explosions

The fish washed up on the shores of a river about 6km from the blast site. Credit: Reuters

Thousands of dead fish have washed up near the site of two explosions which killed at least 114 people in China, prompting fresh concerns about environmental damage from the blasts.

The fish washed up on the shores of a river about 6km from the blast site in Tianjin.

Authorities claimed oxygen deficiency was behind the deaths, not poisoning, saying they did not find dangerous levels of sodium cyanide in the river.

City officials have repeatedly said contaminants found in the wake of the August 12 explosions, including deadly sodium cyanide, pose no risk to the public.

"The immediate cause of the dead fish, in my opinion, is low oxygen saturation," said agricultural department researcher Jiao Jianhua.

"We set up three collection sites, but oxygen saturation from two sites was three milligrams per liter, the last one being just 0.3 milligrams per liter.

The national standard of oxygen saturation is five milligrams per liter.

Residents nearby said it was not the first time they have seen dead fish.

"We used to see dead fish before, almost every year, but the problem didn't attract that much attention," said a one local resident.