The Current11:38How our discarded drugs are sparking sex changes in fish
What do fish act like on anti-anxiety medication? According to Karen Kidd, “they get bolder” and don’t rely on their usual survival skills — and that’s part of a big problem.
“Fish are swimming around in the soup of drugs … and a drug that’s great for us is not so great for the fish,” Kidd, the Jarislowky Chair in Environment and Health at McMaster University and a water pollution researcher, told The Current host Matt Galloway.
The problem extends to a number of chemical compounds humans take daily. It’s become both pervasive and urgent, according to a group of researchers who are calling on the pharmaceutical industry to take swift action to make drugs more biodegradable.
Researchers have known for years that pharmaceuticals are working their way into the water systems, where wildlife interact with them. When drugs are not metabolized fully by the human body, the excess is expelled into wastewater systems.
Kidd says that proper wastewater treatment is part of the solution, but some compounds cannot be completely filtered out, making greener drugs necessary to curb the problem.
“We need to think about the entire life cycle of drugs … as we develop new ones, because we can’t design wastewater treatment plants to remove all of the drugs that we use,” said Kidd.
“It’s financially [and] technologically not possible.”
‘Everywhere we look … we can find drugs’
In the case of anti-anxiety medication, smaller fish, which usually stick together in schools, stray away from the group and become more susceptible to predators.
In her research, Kidd has also found that concentrations of birth control in water systems have a feminizing effect on flathead minnows. She found traces of estrogen in water alter the reproductive systems of male fish, leading to a drop in the species’ population.
Even coffee contributes to the problem — caffeine is one of the top three most common drugs Kidd says shows up on water tests.
“Everywhere we look, from rural systems to large urban centres, we can find drugs. And they’re on every continent and [in] many of our surface waters,” said Kidd.
Almost half of all municipal wastewater worldwide is not properly treated, according to Kidd, the bulk of which are in lower- and middle-income countries.
While other aquatic animals are also susceptible to the impacts of pharmaceuticals in their environment, fish often suffer the most, according to Juan José Alava, principal investigator of the Ocean Pollution Research Unit at the University of British Columbia. Because fish breathe through gills, Alava says any drugs in the water enter their bloodstream directly.
“Once it is in the bloodstream, that’s when [pharmaceuticals] mess with the physiology and reproductive systems,” said Alava.
‘Benign by design’
Kidd and her co-authors say drugs should be designed not only with human health in mind, but the health of the environment, as well.
This approach, known as “benign by design,” involves making pharmaceuticals so their active ingredients biodegrade naturally.
“They don’t persist, they are broken down, maybe by sunlight or bacteria. So once they’re out of our bodies, they don’t … have effects on our wildlife,” said Kidd.
Fluoroquinolone antibiotics, which are used to treat respiratory and urinary tract infections, are an example of a drug that’s been developed to break down more easily, according to Kidd. While researchers found that none of the substances in the antibiotic medication could be classified as “readily biodegradable,” the insights were a first step in designing cleaner drugs.
Kidd says the “polluter pays” principle adopted in the European Union, which makes pharmaceutical and cosmetic companies responsible for 80 per cent of the cost related to cleaning up harmful substances in waterways, is also promising. She hopes it will incentivize drug makers to design products in a way that leaves no trace.
Alava agrees that greener drugs are the best, most proactive approach. Alongside development within the industry, he says upgrading wastewater treatment facilities should also be a priority for governments.
A new water treatment facility for the Vancouver area has been in the works for over a decade now and has ballooned in cost by billions of dollars. The current, out-of-date primary treatment system only filters for physical waste that either floats or sinks.
On an individual level, Kidd and Alava both say everybody can make a difference by returning unused prescriptions to their pharmacy where they will be disposed of properly, rather than flushing them down the toilet or throwing them in the garbage.
“The personal changes need to go hand [in] hand with the efforts from the industry, with innovation and with political will. If we put together this effort, I think we can really create a … more sustainable future,” said Alava.
