Polish authorities have pointed to a toxic algae as responsible for the death of nearly 250 tonnes of fish in the Oder River last summer, excluding the hypothesis of industrial pollution, in a preliminary report announced Thursday, September 29.
The authors of this report, the details of which will be made public on Friday, have at the same time recognized the poor quality of the river's water "
for years
", accentuated this summer by high temperatures and very high water levels. low that could have favored the proliferation of these algae.
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“
A hyper-saturation of the waters by oxygen, radically increased hydrogen potentials (...) a drop in biogenic substances, the decomposition of the biological tissues of the fish (...), led us to conclude that the death of the fish was probably caused by the toxic impact of the algal bloom
," said Agnieszka Kolada of the Polish Institute of Environmental Protection.
Tense relations between the two countries
The incriminated micro-algae, identified as Prymnesium parvum, also called "
golden algae
", is common in estuaries and normally develops in brackish waters, mainly near the seas, and "
has never been identified in Poland
,” said Agnieszka Kolada.
"
The death of the fish was not caused by heavy metals, pesticides or hydrocarbon substances
", according to the theses of the document commissioned by the government and presented to the press.
According to the analyzes carried out so far, "
none of the establishments checked has discharged polluting substances exceeding the authorized standards
" into the river, which various environmental organizations and the media had suspected, insisted the head of the government directorate for Environmental Protection, Andrzej Szweda-Lewandowski.
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The volumes of discharges were "
the same as in previous years
", he assured.
The disaster has somewhat strained relations between Poland and its German neighbour, with Germany accusing Poland of delaying informing it of the extent of the pollution.
In Poland, the government has come under fire for not taking swift action.
