The river that runs through the grounds of Glastonbury Festival is contaminated with “damaging” levels of MDMA and cocaine, according to a new study conducted by environmental researchers at Bangor University in Wales. The likely culprit behind the contamination? Festival-goers urinating on the ground en masse, of course.

As Bangor University’s Dr. Christian Dunn said, per the BBC, “Our main concern is the environmental impact. This study identifies that drugs are being released at levels high enough to disrupt the lifecycle of the European eel, [a protected species] … We [also] need to raise awareness around drug and pharmaceutical waste – it is a hidden, worryingly-understudied yet potentially devastating pollutant.”

The study was conducted during the 2019 edition of Glastonbury, which drew more than 200,000 attendees. Researchers tested for popular illicit drugs in the river before, during, and after the festival both upstream and downstream of the event site, with additional tests in the neighboring Redlake River serving as a control group.

The tests found cocaine; benzoylecgonine, the major metabolite of cocaine; and MDMA, commonly known as ecstasy, at all sample sites. The results showed significantly higher concentrations and mass loads (mass carried by the river per unit of time) downstream of the festival in Whitelake river.

Per the report’s abstract, “MDMA mass loads were 104 times greater downstream in comparison to upstream sites. … Cocaine and benzoylecgonine mass loads were also 40 times higher downstream of the festival.”

The timing of the spike in concentration and mass load of MDMA and cocaine in Whiltelake River also indicates that Glastonbury is likely culpable for the contamination.

“MDMA reached its highest level [in Whitelake River] during the weekend after the festival,” the study continues. “This concentration is deemed harmful to aquatic life … and provides evidence of continuous release after the festival due to leaching of MDMA from the site.”

Redlake River, meanwhile, experienced no significant changes in any illicit drug levels, further indicating that drug release was likely dependent on the festival site.

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The researchers came to a relatively unsurprising conclusion about how to stop the contamination in the river at Glastonbury: to paraphrase, “Stop pissing on the bloody ground and use the toilets, you knobs.”

According to a spokesperson from the Glastonbury Festival, per BBC, “We are aware that the biggest threat to our waterways – and the wildlife for which they provide a habitat – comes from festival-goers urinating on the land. … This is something we have worked hard to reduce in recent years through a number of campaigns, with measurable success. Peeing on the land is something we will continue to strongly discourage at future festivals.”

The festival spokesperson also reiterated that Glastonbury still does not condone the use of illegal drugs in the first place but, you know, good luck with that.

You can review the full report from Bangor University environmental researchers here.

[H/T Reuters]