Kim Malcolm talks with Seattle Times reporter Lynda Mapes about a new study that looks at the impact of drugs picked up by juvenile Chinook salmon in Puget Sound.
[asset-pullquotes[{"quote": "Interview Highlights", "style": "wide"}]]What types of drugs are being found in salmon?
Mapes: Virtually anything in your medicine chest is showing up in Puget Sound, and it's showing up in the fish. By the way, that also includes illegal drugs. Cocaine for instance, that's showed up. And of course, all the usual suspects – everything from antidepressants to anti-histamines to antibiotics by the score. It’s an alphabet soup of chemicals that’s getting into the water.
Why is this happening?
It’s happening because when people go to the bathroom, they express these drugs in their urine. That goes off into the wastewater treatment plants, which cannot cleanse this stuff from our waste stream. And so it goes out into Puget Sound.
This new research looked into how the drugs are affecting fish and, in particular Chinook salmon. What is this research showing?
What was so poignant to me is what’s now happening when these fish need to be getting as big as they can, as fast as they can, so that they won't be eaten by a predator. They need to put on some body fat for winter. Instead, what happens because of the toxic effect of these drugs is their bodies actually mimic starvation. Their systems shut down because they're dealing with this toxic loading.
And when they shut down what happens to them?
They don't grow. Not only that, but they could be less fit. They're less able to avoid predators. Everything about what a fish needs to be – fast growing, fast moving, quick on its fins – that's what they're not.
And what impact is this having on the rest of the food chain. What about orcas?
In terms of a direct loading of these drugs, the amounts are small and the fish are small. Orcas are eating adult salmon, of course. But here's the problem: It is depressing the fitness of these Chinook salmon.
Puget Sound Chinook are threatened. We don't have enough of these fish and the orcas are literally starving. So anything that is potentially limiting the fitness of these fish, such that they don't grow to adults, is a problem for orcas.
What can be done to prevent this from happening?
Well I hate that question because unfortunately, I really don't have a good answer for you. At this point, wastewater treatment plants can't filter out these materials. By the way, there's a lot of other stuff that they can't filter out, including nitrogen.
There's an enormous amount of nitrogen loading into the system as well. But in places where outfalls are in much deeper water, faster moving water, such as by the bay at West Point, "better dilution is the solution to pollution," as they like to say. And it is a true. So some of this can be engineered to be less of a problem. But of course, retrofitting any of these sorts of plants is extremely expensive, and that's a cost that has to be examined in competition with lots of other things.
