Poisonous algae killed fish in Oder River

Polish scientists have confirmed a suspicion that toxic algae killed thousands of fish in the Oder River that runs between Germany and Poland, reported dpa.

"The reason for the fish kill was most likely the toxic effect of an algae bloom," aquatic biologist Agnieszka Kolada of the Institute for Environmental Protection said at the presentation of a preliminary report on Thursday.

The Polish Ministry of the Environment had commissioned a group of 49 scientists from 14 research institutes to identify what caused the environmental disaster earlier this year.

Officials have been trying to identify what led to the deaths of tons of fish in the river which runs south to north between Germany and Poland in August.

Kolada said Poland had identified 249 tons of fish carcasses.

Polish and German scientists found evidence of Prymnesium parvum, a species of algae that can form a toxin that is deadly for fish in water samples taken in both countries.

Polish officials took a total of 221 water samples from different sections of the Oder River between August 12 and September 8, Kolada said.

They detected Prymnesium parvum in 78% of the samples. Poland has never detected this type of algae in the past, she said.

Tests of dead fish and shellfish also indicated that the toxin caused their "sudden, rapid" death.