The mass die-off of thousands of fish, which sparked a political row between Poland and Germany, has been blamed on toxic algae.
Nearly 250 tonnes of dead fish were recovered in August from the Oder river, which runs through the two countries.
There had been accusations that a chemical spill had caused the die-off, with Poland and Germany denying any responsibility.
But on Thursday, Polish authorities said that toxic algae — worsened by high summer temperatures and low water levels — was behind the incident.
Various factors “led us to conclude that the fish deaths were probably caused by the toxic effects of an algal bloom”, said Agnieszka Kolada from the Polish Institute of Environmental Protection.
The micro-algae at issue — known as golden algae — is found in estuaries, mainly near the sea, and “had until now never been detected in Poland”, she told reporters. She added that the water quality of the Oder has been poor “for years”.
Poland is due to release a full government-commissioned scientific report on the die-off on Friday.
“The fish deaths were neither caused by heavy metals, nor pesticides, nor petroleum substances,” according to a presentation on the report.
The mass die-off was first detected by locals living along the 840km waterway, who were then warned not to swim in the river or to touch it.
(Source Euronews)
