Numlock Sunday: Natasha Gilbert on the pharmaceutical waste polluting fish
By Walt Hickey
Welcome to the Numlock Sunday edition.
This week, I spoke to Natasha Gilbert who wrote “The Search for What’s Harming Florida’s Beloved Bonefish” for Hakai Magazine. Here's what I wrote about it:
A new study tried to find out why the population of bonefish in Florida was in decline, and tested the fish for concentrations of pharmaceuticals that entered into the ecosystem through sewage. The lab results from the fish sampled resembled the parking lot of a Phish concert: Across the 93 fish sampled from South Florida they found high levels of 58 different pharmaceuticals, with every fish having at least one medication turn up in its blood and some fish having up to 17 different meds. The bonefish hunt prey that are themselves contaminated with the medications, and the drugs combine in the bonefish in ways that could be driving the bonefish demise.
We spoke about how pharmaceuticals get into the watershed, why large manufacturers share lots of the responsibility, and how wastewater treatment needs to improve to save the bonefish.
This interview has been condensed and edited.
You wrote a really fascinating story, all about the ways that pharmaceuticals get into fish. Can you tell me a little bit about the bonefish?
They're around South Florida and other places as well, the Caribbean, but very popular around South Florida for sport fishing. Recreational fishermen like them because they're quite difficult to catch, they swim quite fast and they enjoy it, and so they're regarded as one of the big five to catch of fish out there. They've been very popular over many years, but what fishermen have seen is they've become harder and harder to catch over the past 20 years or so. And the size of the fish that they're catching is small as well: South Florida used to be well known for the size of the fish; now they're much reduced in size as well. That's partly because the population is not as healthy as it used to be.
I thought it was so remarkable reading your story that the alarm was sounded by the fisherman, that this community that has a very long-standing relationship with the fish was the first to say that there's an ecological issue.
Yeah, part of the reason that is the case is because there just aren't enough scientists, and there isn't enough money to monitor every species and every animal. The scientists weren't looking that closely at them, but the fishermen were, and they noticed it and so they flagged it and some of the numbers that the scientists use now come from the fishermen. And they work closely with the fishermen to continue to monitor and get a feel for whether the populations are rising or falling. They're also trying to figure out the breeding behavior of bonefish; scientist don't really know much about this. The fish go offshore to breed and they have some particular type of behaviors, but they’ve never really been able to pin down where they actually breed. The fishermen are helping them out with that information, so they've been instrumental in working on this kind of problem.
What I love about this story is there have been many fish populations that have taken a dive and typically we're able to track that to a very physical reason: too much extraction or too much overfishing or too poor management. You wrote about how they were finding antidepressants and opioids and pharmaceuticals in these fish that were potentially causing issues. How the heck does that happen?
Predominantly it comes from people using medication and you excrete it out into wastewater and the wastewater treatment plants don't have the technologies to remove the pharmaceuticals, and so a large proportion of what goes in one end comes out the other. All the water that comes out the wastewater facilities and goes into rivers and streams and into the ocean still contains very high levels of pharmaceuticals. They also come from pharmaceutical manufacturing facilities, there's a bunch in that area as well. When they clean their instruments, they wash it out in very high concentrations of the pharmaceutical that they're manufacturing. That's pretty much where it comes from.
Can you expand on that a little bit? You wrote a little bit about how untreated sewage can be a problem as well, is the other thing.
The wastewater infrastructure around Florida is pretty old and decrepit, so you have a lot of leaking pipes. The wastewater that is going from houses to the wastewater treatment facility, that could leak into the soil and then that will trickle down through the earth and find a river or a stream or find its way out into the ocean, because it's near the ocean. Also a lot of the houses around there are not connected up to a main wastewater treatment facility, that still use septic tanks and can overflow and can leak and that will trickle down into the soil and now into the water bodies. That untreated waste water will still contain very high levels of pharmaceuticals.
It goes into the water and it can find its way into the fish. The water will come into the fish over its gills and the pharmaceuticals will transfer into the blood stream, but also they'll consume the pharmaceuticals when they eat their prey. These little crabs and shrimp that live in the sediment, they also become contaminated, and very highly contaminated, because they live in the sediment and what happens is that the pharmaceuticals will sink down from the water into the sediment and become highly concentrated. And you've got these little shrimps and crabs living in there and they become very highly concentrated.
The fish, the research has found, they sampled 93 fish from around South Florida and they found high levels of up to 58 different types of pharmaceuticals — a lot of heart medication, antidepressants, antibiotics, and some of these fish had up to 17 different drugs in one fish. If you think about when you go to the doctor, they're very concerned about making sure you're not taking different types of drugs at the same time, because they mix and they have all these interacting properties and that's all going on in the fish. So it's not good for the fish.
You wrote a little bit about how there was a study that found that, what was it, salmon exposed to anti-anxiety meds were a little bit more risky. Could you talk a little bit about what this might actually do to the fish?
There are some studies that look at antidepressants, some of the drugs that have been studied. Some of the results suggest that it affects the fish migration and spawning behavior and this is important because if you mess up that particular behavior, it can affect the survival of not just the individual fish, but the population as a whole. In some studies it has made the fish take more risks; if you give them an anti-anxiety, you can imagine they become bolder and then they become more likely to be preyed on. So they won't survive to make it down into their migration and are less likely to be able to spawn and regenerate the next population.
You've talked a little bit about how this challenge is particularly difficult to fix. What are some of the ways that people want this addressed?
Definitely improving the wastewater infrastructure, that's absolutely key. So either improving the wastewater treatment plants with technologies that can remove some of the pharmaceuticals, or also fixing the pipes so that they're not just spewing out raw sewage into the sea. Those would be the main things, but other things include avoiding throwing your unused pharmaceuticals down the toilet, that can contribute as well. It's at high levels in the wastewater of pharmaceutical manufacturing facilities. They can improve the way that they clean their facilities so that they're not washing extraordinarily high levels of pharmaceuticals just out into the wastewater.
Can you tell me a little bit about your work in general? I know this was your first contribution to Hakai, but we'd love to hear more about your work as a whole.
It was great working with Hakai, I felt like the editors there really made the story stronger, but generally, I've been interested in issues about pharmaceutical pollution for a while. I've been following it up in a number of stories on this topic. It's not as widely covered as some of the other pollution problems that we have, but I feel like it's a really important one that's just going to become more and more so over time.
A couple of years ago, I did an investigation for STAT which looked at pharmaceutical manufacturing facilities, which is why I keep banging on about these guys, because the investigation revealed that these facilities, as they produce the drugs, the entire rooms and all the machinery would just become covered in thick dust of the medications and they would just hose it down and wash it all down straight down the drain, and some of the numbers were shockingly high, way above the safe levels for wildlife. I predominantly look at environmental sustainability issues, including agriculture as well, and some women's health stories.
Can you tell me where folks can find you and your work?
I have a website, it's bynatashagilbert.com. I'm on Twitter and Instagram where you can see some of my photos.