The 180

Why this fish biologist stopped eating fish

Over the past decade especially, we've heard a lot about the benefits of eating fish. But aquatic scientist Laura McDonnell says we might be overlooking the health risks. She's given up eating fish, and thinks the rest of us should think about it, too.
Fish is often thought of as a healthy food, but Laura McDonnell says there are risks we're forgetting. (Curtis Rumbolt/CBC)

Aquatic scientist Laura McDonnell has given up eating fish.

In an essay originally published in The Walrus, McDonnell, a biologist at McGill University, says despite its reputation as a healthy source of protein, what she has learned by working in her field has turned her off.

Her first concern is plastic.

"It's not really debatable that fish are eating plastic. It's been found in the stomachs of tons of different species. Everything from marine mammals to seabirds to smaller fish to crabs, mussels, oysters. So they're definitely eating it. And even though the science is still a bit in its infancy in terms of detecting what types of toxicity that might bring to humans, it's just definitely something to keep in the back of your mind... we know how much of it is in their guts, in terms of how much of that is actually transferred to their tissues that we're eating - in terms of mussels or oysters you eat the entire thing, so definitely you're probably eating plastic in that case, but in terms of a regular fish filet, it's not really known yet how much could actually be in there."

But in addition to that, McDonnell warns you may not be eating the type of fish you ordered in the first place.

"Basically there've been quite a few studies that have come out recently that have tackled this. The big one was done by Oceana, and they found that one in five of over 25,000 seafood samples was mislabeled, and this was a global study. Sushi restaurants in particular had the highest percentage of mislabeling, but grocers, they also saw it there, and in restaurants. Pretty much everyone that you'd be getting your fish from, it's been detected."

McDonnell says while she's not trying to convince other people to give up fish, she does think they should consider the broader issues.

"These are issues that are increasing in prevalence. If these things do concern you, start asking questions. If you live on the coast, great, then you can at least know where your fish is coming from... you know, my family, my friends, they still eat fish. I just wanted people to be aware."


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