Scientists have found that drug remnants in the nearby Fyris river multiplied to dangerously high levels after the party was over.
”During upcoming festivals the organizers must ensure that there are enough portable toilets in the area and urge the festival-goers not to urinate outdoors, as this is what leads to medical products leaking into the river water,” said Atlasi Daneshvar, a PhD student at the Deptartment of Aquatic Sciences and Assessment at Uppsala University, to local paper Upsala Nya Tidning (UNT).
For two years in a row, scientists have conducted tests before, during, and after the festival at various locations by the river.
They found that during the year when the weather was good, they saw almost no changes in the levels of drug remnants in the water.
However, the next year, when the festival weekend was bogged down with rain, traces of drugs and medicinal residue in the river water multiplied, according to UNT.
The most common drug found in the water was reportedly ibuprofen, a substance used in many popular painkillers, but more worryingly, scientists also found remnants of drugs such as epilepsy medicine at levels that could be a direct danger to the environment.
The study was conducted by scientists at the Swedish University for Agricultural Sciences (Sveriges lantbruksuniversitet, SLU), Uppsala University and Åbo Akademi University in Finland.
It has been published in the Journal of Environmental Monitoring.