Drugs in Our Bodies Become Drugs in Our Water

When people take drugs, either for legitimate medical reasons or to get high, they eventually eliminate traces of those drug through the body’s waste products. Those traces then enter our water supplies. When wastewater is processed to make it safe to flow into the sea, this processing does not remove all traces of drugs the humans in that area were consuming.

Elliott Bay in Seattle, Puget Sound
Elliott Bay and Downtown Seattle, Washington.

Thus it is possible to find traces of drugs in our water and now, in our shellfish. New testing of Puget Sound mussels has found that they tested positive for opioids like heroin, fentanyl, OxyContin, Vicodin and other drugs.

The testing took place in 18 urbanized locations around Puget Sound in Washington State. Clean mussels from remote areas were placed in these test locations. They were later examined for any traces of opioids or other drugs. The mussels from Elliot Bay and Bremerton Shipyard tested positive for opioids.

The drugs found included not only opioids but also antidepressants and the common chemotherapy drug Melphalan.

European Water Tests Show Similar Results

In 2017, the European Monitoring Centre for Drugs and Drug Addiction reported on an extensive project testing wastewater for drug traces. In all, 19 European countries and more than 50 cities were involved. The study focused on traces left by the use of stimulants like cocaine, amphetamine or Ecstasy (MDMA).

This study found that cocaine use was highest in western and southern European cities, especially in Belgium, the Netherlands, Spain and the United Kingdom. In Eastern Europe, cocaine use was low.

People on a street near the Tower Bridge.
London near the Thames River.

Amphetamine traces were found highest in northern and eastern Europe but were lowest in southern regions. Ecstasy traces were highest in Belgium, Germany and the Netherlands.

A 2015 report on drugs in London’s wastewater found that the city had the highest average daily concentration of cocaine traces of any European city. For Ecstasy, the city was in fourth place.

American Students and “Study Drugs”

In 2013, a similar study was performed using wastewater on unidentified American college campuses. In this case, the study sought to determine the presence of residues from drugs referred to as “study drugs.” These are stimulants such as Ritalin (methylphenidate) and Adderall (mixed amphetamine salts). They are prescribed for problems focusing on specific tasks but they gain the reputation among college students as enhancements for study. As stimulants, they enable students to stay awake for long hours so they can study for finals or complete papers. Unfortunately, they are also addictive and can ruin a person’s hopes for an education.

College students studying in a group.

This study analyzed wastewater during the first week of classes and then compared it to samples taken during more stressful times of the school year, such as finals weeks and midterms. These stressful weeks seemed to show higher levels of amphetamine traces. The highest results showed up during finals week of the second semester. Traces of methylphenidate climbed gradually during the first semester but had no definite trends in the second semester.

Testing wastewater takes all the guesswork out of drug use by Americans or Europeans. No matter what answer people might give to a survey asking about drug use, a wastewater test tells us the truth. And now that drug traces have been found in Washington State’s shellfish, we have proof that these drug residues can be significant enough to show up in animal bodies as well.


Karen Hadley

For more than a decade, Karen has been researching and writing about drug trafficking, drug abuse, addiction and recovery. She has also studied and written about policy issues related to drug treatment.