Washington Wastewater Treatment Fails to Remove Drugs | Fluence
Fish contaminants

From left, Stuart Munsch, Andrew Yeh, Monica Chan and Richard Ramsden use a seine to collect fish in the Puyallup Estuary.

Wastewater treatment facilities in the Puget Sound area of Washington State appear to be failing to remove a host of compounds that create a toxic soup for the area’s salmon and other aquatic life.

Prozac, Advil, Benadryl, Lipitor, caffeine, and cocaine are among the compounds found in juvenile chinook studied by NOAA’s Northwest Fisheries Science Center in Seattle.

The researchers found a total of 81 drugs and other personal-care products such as the antibacterical chemical triclosan in the outfall of sewage treatment plants flowing into the sound. The levels detected were among the highest in the nation, compared against a prior study of the 50 largest wastewater treatment plants in the United States conducted by the United States Environmental Protection Agency.

Lynda V. Mapes, environment reporter for the Seattle Times, explained:

The medicine chest of common drugs also included Flonase, Aleve and Tylenol. Paxil, Valium and Zoloft. Tagamet, OxyContin and Darvon. Nicotine and caffeine. Fungicides, antiseptics and anticoagulants. And Cipro and other antibiotics galore.

More Use? Or Less Removal?

There are two possible explanations, said researchers, for the high amounts of compounds found in the water: either people in the area use more of the compounds detected, or it could be a result of the wastewater-treatment plants’ processes. The samples, which were collected over two days in September 2014, included wastewater plant effluent, estuary water samples, and fish found in the Puyallup River estuary in Tacoma’s Commencement Bay, Sinclair Inlet in Bremerton, and the Nisqually River estuary near Tacoma.

Jim Meador, an environmental toxicologist at NOAA’s Northwest Fisheries Science Center in Seattle and lead author of the paper describing the work, told Mapes:

The concentrations in effluent were higher than we expected. […] We analyzed samples for 150 compounds and we had 61 percent of them detected in effluent. So we know these are going into the estuaries. […] [I]t is possible that a substantial load of potentially harmful chemicals are introduced into streams and nearshore marine waters daily.

Wastewater Contaminants Found in Fish

Treated water contamination

A staghorn sculpin, collected in Sinclair Inlet, was one of the fish species studied.

The scientists examined tissue samples from migratory juvenile chinook salmon, as well as samples from staghorn sculpin, a fish resident in the area. The compounds chosen for detection were based on how commonly they are used by people and how likely their continued use is, as well as the potential for future contamination based on continued human population growth in the region.

As a control, researchers tested fish taken from the Nisqually estuary, a body of water near Tacoma, Washington. It has historically served as a reference site for toxicity studies since it has no direct discharge from a municipal treatment plant. These fish also tested positive for various chemicals.

The researchers did not study these compounds in predator species that eat these fish, nor did they look at possible contamination in algae or invertebrates the fish might eat. The potential effect on human health is nominal as humans eat neither of these fish.

‘Contaminants of Emerging Concern’

Based on the total amount of discharge from the two major wastewater treatment plants in the study — 71 million liters per day — the researchers estimate that nearly 300 pounds of so-called “contaminants of emerging concern” likely enter Puget Sound every day. There are 106 publicly owned wastewater treatment plants in the area that discharge into local waters. Leaking septic systems also may be a culprit. The scientists also suspect their work likely underreports the amount of drugs in the water closer to outfall pipes or in deeper water.

“Contaminants of emerging concern” is a term generally used to describe chemicals that are potential water pollutants that aren’t monitored or regulated in the United States because little is known about them.

In his previous work, Meador determined juvenile chinook salmon migrating through contaminated estuaries in Puget Sound die at twice the rate of fish elsewhere. These compounds could be responsible since they potentially affect fish behavior and reproduction, among other deleterious effects. Meador said:

You have treatment doing its best to remove these, chemically and biologically, but it’s not just the treatment quality, it’s also the amount that we use day to day and our assumption that it just goes away. […] But not everything goes away.

Continued Research on Contamination With Pharmaceuticals

Pharmaceutical wastes and other contaminants of emerging concern are causing unknown impacts on aquatic life and water quality worldwide, which some scientists have said makes additional research into this issue essential.

In a similar 2013 study, scientists from Cary Institute of Ecosystem Studies, Indiana University, and Loyola University Chicago examined streams of similar sizes in New York, Maryland, and Indiana, and how six common pharmaceuticals affected these streams’ health. The scientists said most sewage treatment facilities are not equipped to fully remove pharmaceuticals before treated water is discharged into surface water.

Reverse osmosis can remove an estimated 99 percent of contaminants from wastewater streams, including “large pharmaceutical molecules,” according to the World Health Organization. It and other organizations are attempting to educate consumers on the importance of the proper disposal of medications, both over-the-counter and prescription. In some areas there are drug take-back programs for consumers.

The 2013 study and these latest findings could stimulate research into improved wastewater management protocols and treatment technologies.

Meador worked with colleagues from the University of Washington on the study. The work was funded primarily by the Washington Department of Ecology.

The NOAA study — “Contaminants of Emerging Concern in a Large Temperate Estuary” — was published online in advance of publication in the journal Environmental Pollution.

Photos by Andrew Yeh, courtesy NOAA Fisheries Northwest Fisheries Science Center.