PART TWO - ...Continued from Part one

His subsequent research found that oxybenzone damaged coral DNA and caused “severe and lethal deformities” in coral larvae at concentrations as low as 62 parts per trillion, equivalent to a single raindrop in six-and-a-half Olympic-sized swimming pools.

To make things worse, swimmers aren’t the only source of sunscreen’s nanoparticles and organic contaminants. These compounds also enter the water through municipal sewage systems after people shower to wash off sunscreen following a day outdoors; through septic fields that leak into ground or surface waters; even through flushed toilets — researchers found that oxybenzone is detectable in human urine 30 minutes after sunscreen is applied to the skin.

One 2012 study in northwestern Spain found sunscreen contaminants pervasive in sewage, surface and drinking water. Five years later, a study of treated waste water in New York had similar findings.

And Environmental Working Group, a non-profit advocacy organization that concerns itself with toxicity of household chemicals, warns that “when zinc oxide and titanium dioxide nanoparticles wash off skin, they enter the environment with unknown effects.”

While the working group says the metallic nanoparticles are worthwhile because of their effectiveness and public-health value in protecting human skin from UV radiation, it also warns that “the implications for nanoparticle pollution of the environment have not been sufficiently assessed. … Sunscreen ingredients have been shown to damage coral, accumulate in fish and the environment, and disrupt hormones in fish and amphibians.”

Nor is it only the river that concerns Saysell.

“What about Cowichan Lake?” he asks. “Every beach in the lake will have swimmers wearing sunscreen. That’s where our juvenile coho go. They migrate to the lake beaches right after they hatch.”

And while the Cowichan is Saysell’s main concern, there are plenty of other lakes and rivers around the province where families slap on the sunscreen and go for a leisurely float or swim. The Shushwap, Similkameen, Okanagan, Thompson and Kettle rivers all attract tubing enthusiasts. And beach swimming on lakes and rivers is ubiquitous summer fun from the Peace River district to the Fraser Valley and from the Rockies to the coast.

The Cowichan River was listed by the Outdoor Recreation Council of B.C. as one of B.C.’s most endangered rivers in 2018. It made the list in 2016, too. Habitat damage, low summer flows and high water temperatures that hurt juvenile fish survival were reasons for the listing.

A study by the Cowichan Valley Regional District estimates that on average, the number of returning spawners for Cowichan River coho and chinook, the juveniles of which spend a year rearing in the river, have declined by approximately 90 per cent.

Although trout stocks are generally considered healthy, spawning returns of chinook declined by 56 per cent from 1995 to 2006. These large chinooks, prized by sports anglers dwindled from returns of more than 25,000 to about 1,300. The stocks have begun to rebuild, probably a result of reductions in the harvest coupled with improved marine conditions. In recent years, returns reached 8,000 but remain a shadow of past abundance.

Cowichan River coho, too, declined steeply. Historically, coho returns to the Cowichan exceeded 70,000. By 2007 they had declined to fewer than 1,000. And steelhead are a concern in many Vancouver Island rivers, including the Cowichan.

Solutions
What’s to be done?

First, Saysell hopes, swimmers and tubers will educate themselves about sunscreen’s effects and look for brands that don’t include the most problematic compounds. And he says we should all start thinking about other alternative behaviours — wearing beach clothing that blocks UV, for example — that can help reduce sunscreen use. Authorities, he says, also need to educate themselves about how to manage and reconcile the conflicting values of promoting sunscreen use for worthwhile public health with its serious, however unintended, ecological side-effects for other species.

Second, he says, provincial and federal environmental authorities should start paying attention and begin systematically collecting accurate data.

“Where has all our insect life gone?” he asks. “Well, the province has never done a comprehensive study of the biomass of those insects in the Cowichan River, so we don’t know. We need detailed studies of the river’s insect life.

“These insects are the canaries in our coal mine. They are what sustain all the life in this river. Fish, birds, frogs — without those insects we’ll lose all the life in this heritage river. It’s the death of 1,000 cuts, you know. Death of 1,000 cuts. And it’s all going to unravel suddenly.

“Our grandkids are going to say: ‘You had such a paradise and you couldn’t ruin it fast enough.’”

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