Scientists studying freshwater shrimp in British waterways have made an eye-opening discovery, according to a new study: All the shrimp they looked at tested positive for cocaine.
“Such regular occurrence of illicit drugs in wildlife was surprising,” study author Dr. Leon Barron of King’s College London said in a statement released by the school. “We might expect to see these in urban areas such as London, but not in smaller and more rural catchments.”
To carry out the study, King’s College and University of Suffolk researchers caught shrimp from 15 different sites across England’s Suffolk County, which is a more rural area on the coast northeast of London. Their research focused on the presence of various micropollutants — or harmful chemicals found in trace amounts — in the tiny aquatic animals.
The presence of cocaine isn’t the shrimps’ fault, according to the study. Researchers said drugs and consumer products frequently make their way into rivers after they’re used by humans, which can damage animals and the environment.
“Although concentrations were low, we were able to identify compounds that might be of concern to the environment and crucially, which might pose a risk to wildlife,” lead author Dr. Thomas Miller of King’s College said in a statement.
Beyond cocaine, illegal pesticides, pharmaceuticals and ketamine “were also widespread in the shrimp that were collected,” the study found. Researchers’ findings were published this month in the journal “Environment International.”
Still, the impact those pollutants could have on wildlife isn’t yet clear, according to researchers.
“As part of our ongoing work, we found that the most frequently detected compounds were illicit drugs, including cocaine and ketamine and a banned pesticide, fenuron. Although for many of these, the potential for any effect is likely to be low,” Miller said.
And the English scientists still don’t know if their findings would hold true elsewhere.
“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,” Professor Nic Bury of the University of Suffolk said in a statement.
But he added that “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.”
The university news release on the study said it’s the first time researchers have discovered “a diverse array of chemicals, including illicit drugs and pesticides in UK river wildlife.”