Drug pollution is hurting marine life, but veterinarians can help
Hundreds of human-made chemicals flow into U.S. streams and waterways. Dana W. Kolpin, a research hydrologist for the U.S. Geologic Survey, said wildlife interacts with those products in unpredictable ways.
"In the real world, a fish or an earthworm or whatever is not just getting hit with one compound at a time," he said. "It's getting hit with this complex soup of contaminants, all of them maybe at low levels.
"And that's the thing: Individually, they may be fine at low levels. But en masse, in this soup mixture, you put them all together and there could be these unintended additive, synergistic effects."
The pharmaceuticals in that mix—and products of their deterioration—arrive in water discharged from wastewater treatment plants, passed through tile drains from manure-fertilized fields, washed off livestock farms, or leached from landfills and septic systems.
"Anything we use, whether it's household or on the farm, has the potential to become an environmental contaminant," Kolpin said. "That's something I've come to appreciate more and more as I dig into this."
One of the bigger concerns is unused drugs that are flushed down the drain.
"How much is from normal use and proper use, and how much is from disposal or improper disposal?" he said. "Those are the really hard numbers to figure out."
Throwing unused medicine into a toilet was a more common practice 20 years ago, he said, but it remains part of today's pollution problem. It also is the easiest source of contamination to reduce.
Anything we use, whether it's household or on the farm, has the potential to become an environmental contaminant."
Dana W. Kolpin, a research hydrologist for the U.S. Geologic Survey
Danger downstream
From 2012-14, USGS and
Environmental Protection Agency scientists collected water samples from 38 streams across the country and tested for about 720 human-source contaminants. They found more than 400, including about 230 active drugs and poisons (Environ Sci Technol 2017;51:4792-4802).
The Result of Improper Medical Waste Management
The number of contaminants ranged from four in a creek near a small Arkansas town to 161 in the Chicago Sanitary and Ship Canal, with a median of 70. Higher total concentrations correlated with nearness to city wastewater. The contaminants are dangerous to fish, insects, and other life, which can be more sensitive to contamination in low concentrations during development and growth. The pollutants can kill, prevent reproduction, change behavior, and alter appearances, the article states.