Scientists testing Suffolk’s rivers for traces of chemicals have found cocaine in every sample they analysed.

Eastern Daily Press: Prof Nic Bury collecting samplesProf Nic Bury collecting samples (Image: Archant)

The surprise findings came after researchers from the University of Suffolk collected freshwater shrimps from 15 different locations on the rivers Alde, Box, Deben, Gipping, Stour and Waveney. The tiny water creatures were then sent to a team at King’s College London to be analysed.

Widespread

Low levels of cocaine were found in the systems of all the shrimps tested, while traces of other illicit drugs, such as ketamin and alprazolam - an anti-depressant drug often used for recreational purposes - were also widespread.

Professor Nic Bury from the University of Suffolk, who took the samples last summer, said the main aim of the study had been to search for the presence of pesticides and that the tests for pharmaceutical and illegal drugs were secondary.

Eastern Daily Press: Cocaine was also found in the River Alde. Picture: SARAH LUCY BROWNCocaine was also found in the River Alde. Picture: SARAH LUCY BROWN (Image: Archant)

“I had no idea that cocaine would be there in all samples,” said Prof Bury, a specialist in aquatic toxicology, who added that the cocaine, which was found in concentrations of between three and five parts per billion, is likely to have passed through users of the drug via the sewer system and into the rivers.

READ MORE: Impact of neonicotinoids in River Waveney unknown, says Environment Agency

Pesticides

Eastern Daily Press: Freshwater shrimp taken from six Suffolk rivers were testedFreshwater shrimp taken from six Suffolk rivers were tested (Image: Archant)

“There’s a plethora of micro-pollutants at low levels found in these animals -it is indicative of our society and the drugs we take. Whether they be pharmaceutical or illicit there is a consequence to the environment.”

Traces of a number of controversial neonicotinoids pesticides, which have been shown to affect bees, were also found in the shrimps while a banned pesticide fenuron was also discovered. Prof Bury said the presence of this banned compound was likely to be caused by old traces of the chemical that have remained in soil close to the rivers.

Published

The results, which are to be published by the academic journal Environment International this week, are expected to cause a lot of interest in scientific circles, as few studies of this kind have been undertaken. Prof Bury says more work is needed to find out whether these chemicals are affecting the behaviour of water creatures and how widespread the problem is.

Eastern Daily Press: The River Stour at Flatford Picture: MICK WEBBThe River Stour at Flatford Picture: MICK WEBB (Image: capelman)

He added: “Whether the presence of cocaine in aquatic animals is an issue for Suffolk, or more widespread an occurrence in the UK and abroad, awaits further research.”

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How did cocaine get into Suffolk’s rivers?

Eastern Daily Press: The River Deben at Martlesham CreekThe River Deben at Martlesham Creek (Image: (c) copyright newzulu.com)

Commenting on the findings of the study, Dr Leon Barron from King’s College London said: “Such regular occurrence of illicit drugs in wildlife was surprising. We might expect to see these in urban areas such as London, but not in smaller and more rural catchments.”

But this beggars the question, just how did cocaine find its way into every major river catchment in Suffolk?

Professor Nic Bury says the most likely route is through the urine of drug users into the sewer system and then out into the river network via small sewerage treatment works.

He discounted anyone dumping the drugs into a river as a potential explanation. “The presence of cocaine is too widespread for this to be the cause,” he said.

“I was very surprised at the findings - it was the last thing I was anticipating and it is that which makes it such an interesting observation. The simple answer is we don’t know the source of the drugs and more work is required.”

Eastern Daily Press: The River Waveney Picture: BARRY PULLENThe River Waveney Picture: BARRY PULLEN (Image: Archant)

What effects will the drugs have on wildlife?

While traces of cocaine and other illicit drugs found in the freshwater shrimps are in low concentrations - parts per billion - they still may have an effect on the behaviour of the small creatures, according to Prof Bury, who says more research is needed to find out.

He said: “Shrimps have similar receptors to humans, so if you think about how cocaine affects people’s behaviour, the first point of call would be to look at changes in behaviours. Are the shrimps avoiding light or moving more rapidly?”

Prof Bury said traces of cocaine were also found in a number of other invertebrates, such as mayflies, although there is no evidence to show the drug has moved up the food chain into the fish population.

Eastern Daily Press: A walk around the lakesA walk around the lakes (Image: (c) copyright citizenside.com)

He added: “However, the impact of ‘invisible’ chemical pollution - such as drugs - on wildlife health needs more focus in the UK, as policy can often be informed by studies such as these.”