New study finds artificial turf fields in Metro Vancouver are releasing chemicals harmful to salmon

A new study from the University of British Columbia is raising concerns about the environmental impact of artificial turf fields in Metro Vancouver that, it says, are leaking a chemical that is lethal to coho salmon.

the study, Published this month The study, in the journal Environmental Science Processes & Impacts, found that farms release a chemical called 6PPD-quinone into stormwater systems that can eventually make its way into rivers and streams when it rains.

Researchers traced the contamination to crumb rubber infill, which are tiny black pellets commonly used in artificial turf.

“That black rubbery stuff in artificial turf fields is actually used tires on the ground,” said Rachel Scoles, an assistant professor at UBC and co-author of the study. “We thought there was a possibility that when it rained, those little black particles would leach pollutants into the water.”

Scientists collected water samples from 12 areas of Metro Vancouver, as well as stormwater samples from three areas’ drainage systems during rainfall. Artificial turf lasts from one to 14 years.

Researchers say this issue is not limited to new areas.

They found that contamination can persist for years, with farms continuing to release pollutants throughout their lifetime – often more than a decade.

“An average turf field contains about 125 tons of crumb rubber, about 20,000 tires,” said Katie Moloney, a PhD student in environmental engineering at UBC. Scoles Lab.

“With farms typically operating for a decade or more, they can become long-term sources of tire-derived pollution entering stormwater pipes and ultimately fish-carrying waterways.”

Moloney said even very small amounts of the chemical can be harmful.

“The comparison I make is like a drop of water in an Olympic pool,” she said. “Your concentrations can be very low… and that’s enough to kill coho salmon, as well as some other fish species.”

Scoles said the amount of 6ppd-quinone released exceeds lethal concentration values ​​for coho salmon, and would be fatal if they were exposed to it.

Other species, including juvenile cutthroat trout, have been shown to be harmed by the chemical, he said.

Because many turf fields include a drainage layer beneath them, water that runs off collects in stormwater pipes, Scoles said.

That water is then connected to the city’s stormwater infrastructure, or released into surface waters without being treated by a wastewater treatment plant.

“That’s the biggest concern for us,” Scholes said.

stream watchers And environmentalists in BC have raised concerns about the chemical because other studies have shown it is particularly lethal to coho salmon.

Vancouver is preferring synthetic turf

The findings come as the City of Vancouver continues to invest in synthetic turf fields to meet the growing demand for playing space.

According to the Vancouver Park Board 10-Year Sports Sector StrategyWhich was approved in June 2024, the synthetic turf fields make up a small part of the city’s total inventory, 12 out of 151 rectangular fields, but make up almost half of all bookings for such fields.

The report notes that synthetic turf fields can be used year-round without the same maintenance limitations as natural grass, making them better suited to Vancouver’s climate.

According to the city, synthetic fields also recover more than 100 percent of their costs through revenue, while natural turf fields only recover about 10 percent.

But the strategy also acknowledges environmental considerations, including the release of microplastics and the need for better stormwater management systems.

Moloney said these controls are important.

“If we have farms without any kind of treatment system, that’s where the concern starts to arise.”

In a statement, the Vancouver Park Board said it no longer uses crumb rubber infill due to concerns about the chemical identified in the study.

“Our guidelines fully support the use of inert and non-toxic infill materials such as EPDM rubber,” the board said.

Surrey, Burnaby address turf field concerns

Other municipalities say they are also monitoring the issue.

According to the City of Surrey, its artificial turf fields are not located near salmon-bearing streams.

“The infill material used has been tested for composition and meets provincial and national safety standards,” it said in a statement, adding that it has installed catch basins and slit drains to capture contaminants before they reach fish habitat.

The city says it currently operates 18 artificial turf fields and more expansions are planned.

In Burnaby, city staff say they are aware of the emerging research and are monitoring the issue.

“The city plays an active role in the management of our waterways,” a spokesperson said in a statement, adding that staff work with local streamkeeper groups to monitor salmon populations.

How to reduce the risk?

The chemical that harms salmon isn’t the only chemical researchers found in farms. Scoles said there were metals such as copper and zinc, which can be toxic to aquatic life, as well as rubber materials that may have come from the green grassy portion of the turf.

He said municipalities can reduce the risks posed by chemicals to salmon and other species by using alternative turf infill materials such as polymers, although he said they are more expensive.

He suggested, “Another possibility would be to install a treatment system beneath the grounds to capture contaminants that leach from it before they enter the stormwater conveyance system.”