According to a new survey, approximately 40% of Canadian parents are throwing unwanted medications in the trash in a practice that endangers aquatic ecosystems and human health.
In the Angus Reid poll, commissioned by the Health Product Stewardship Association (HPSA) and Drug Free Kids Canada, investigators found that more than half of parents do not consider safe disposal of medications essential.
The survey also revealed that just under half of parents have never talked to their children about how to safely dispose of unwanted medication. This number rises to 58% for parents with children aged 11 to 12.
“We have half a million chemicals on the Canadian market in high production volumes. It’s very difficult to design a sewage treatment plant to deal with all of this,” said Peter Ross, ocean pollution scientist at the Raincoast Conservation Foundation.
Experts say the problem is getting worse.
As drug use increases, litter dumped in sinks and flushed down toilet drains is increasing at a significant rate, according to a recent report of the Organization for Economic Co-operation and Development (OECD).
This is largely due to aging and growing populations, the increase in chronic diseases, and changing clinical practices.
The study, published in May 2022, noted that conventional wastewater treatment facilities were not designed to remove drug residues. Instead, treated sewage sludge redirected for composting or landfill can leak pharmaceuticals into the surrounding water.
The drugs are then ingested by invertebrates and fish and may eventually impact the food sources of top predators.
Scientists have found that accumulated pharmaceuticals can affect animal behavior, immune systems and reproduction, and even lead to increased mortality.
According to Ross, for years there has been strong evidence in London’s Thames of fish species experiencing widespread feminization in sewage treatment plant waters. And while it’s hard to pinpoint the sources, part of the effect could be from estrogen in birth control.
“The highest risk is in freshwater environments,” Ross said. “That old adage is true up to a point: the solution to pollution is dilution.”
This means that anything in a river, lake or stream is particularly vulnerable. Ross points to critical salmon species that spend much of their life cycle in the Fraser River.
Controlled laboratory studies have shown that pharmaceuticals can affect salmon’s behavior, immune system, ability to balance fluids and electrolytes, and odor, Ross says.
Certain drugs stimulate a fish. Narcotics will make them stupid. Immunosuppressants used in organ transplants could reduce a species’ ability to fend off disease.
Ross says anything that affects critical life systems like growth, reproduction, or survival puts species at risk.
But because salmon is a migratory fish species, he says it’s virtually impossible to conduct an experiment that will isolate the impacts of specific pharmaceuticals.
“In the case of our salmon, there’s a big black box in what we know,” he said.
As well as representing a huge volume of wasted healthcare resources, the OECD report also warns that discarded medicines pose a possible public health risk of poisoning if unused medicines are taken from public or private bins, either by accident or intentional misuse.
British Columbia was the first province in Canada to pass extended producer responsibility legislation. In 1997, it passed a law requiring drug companies to set up a program for individuals to return unused drugs. Since then, several provinces have enacted similar laws, in some cases with the HPSA administering drug product declarations on behalf of pharmaceutical companies.
Yet, according to OECD data, Canada still has one of the lowest per capita drug collection rates among its peers. In 2019, Canada collected an average of 20 grams of pharmaceutical waste per person, almost an eighth of that of France and about a fifth of that of Spain.
With so many chemicals in widespread use in Canada, Ross says it’s unrealistic to expect sewage treatment plants to have the capacity to filter it all.
What is needed, he said, is for individuals across the country to take responsibility for old drugs before they go down the drain or down the toilet.
“We in Canada suffer from an embarrassment of riches – huge volumes of fresh water, over 200,000 kilometers of coastline,” Ross said.
“For me, it’s obvious. If there is a way to reduce the release of harmful pharmaceuticals into the environment, it is at the source.