WT: Thanks for doing this John. Tell me, what’s the study about, and why did you do this study?
Wilkinson: Thanks for inviting me, it’s great to talk to you. We are aiming at broadening our understanding of pharmaceuticals in the aquatic environment on a global scale with this project. You are probably aware; we’ve known a fair amount about how pharmaceuticals enter the environment. Over the last two decades, there’s been a decent amount of research on this. Unfortunately, it has not been represented in terms of where samples have come from. Previous to this study we had data only for seventy-five countries of the world, well less than half. Most of our studies originated from Germany, USA and China, we had very few studies outside North America, Europe and some parts of Asia.
With this project, we have created a hub-and-spoke approach to environmental monitoring. We sent sampling kits out to collaborators on all continents, and had the samples returned to us, we analyzed them in here at York, in the UK.
With this, we were able to generate data for 104 countries, well over half the locations in the world, we now have a pharmaceutical fingerprint for nearly half a billion people.
WT: I don’t know where to begin to ask the next questions! We have ibuprofen, Cialis, endocrine disruptors, what did you find, what did you learn on a global basis?
Wilkinson: I will echo your sentiment; I don’t know where to begin to answer! We learned an exceeding amount, as you might imagine. What became clear is that the places we started with two decades ago we now realize have the lowest concentrations, the lowest concomitant risk for affecting the environment. The equipment we use to study this is very expensive and not well distributed around the world. Where we see the highest concentrations of pharmaceuticals and the greatest risk to the environment are the places without access to the instrumentation, places that frankly have not been considered with much research intensity at all.
WT: What kind of equipment did you need to use to find this baseline of pharmaceutical waste in the water?
Wilkinson: We use an instrument called a “High-pressure Liquid Chromatography, Tandem Mass Spectrometry” unit. This has been the workhorse for the field of environmental pollution for the last ten years. Essentially the front end of the process, the chromatography unit separates the molecules we are looking for in our water sample, these are fed into the mass spectrometer, broken into pieces, we count the pieces, and identify the pharmaceuticals.
WT: Can you tell us the top five pharmaceutical waste products that emerged in your global study?
Wilkinson: For context, there are a little over two thousand pharmaceuticals registered for use. I would not be surprised if all two thousand of them are in the water. There are very few studies that characterize the eco-toxicity of these molecules to aquatic organisms. Many of us are doing this work now, to identify the priority molecules.
In terms of frequency of what was detected, the most common is carbamazepine, an anti-epileptic medicine, it is also used to treat nerve pain. This molecule is persistent, it tends to stick around for a while once it’s in the environment. Then there is metformin, an anti-hypoglycemia drug used for type II diabetes and some other conditions, this molecule does not completely break down in wastewater treatment. I think the reason we detect this so much is that the therapeutic dose is high, there is just so much of it.
We found caffeine, more from drinks than medicines. Nicotine is also very frequently detected in the aquatic environment, and acetaminophen, driven by large-scale use of the molecule.
WT: How long have you been working on this?
Wilkinson: It took a little over three years to complete. We applied for funding but got turned down because they said it would “not have enough impact”. We went ahead and did the work in our spare time.
WT: That’s heroic. When you looked at Canada, who did the looking, what did they look at, what did you find here, and how did this compare with the world average?
Wilkinson: I am fortunate to be married to a Canadian, I collected samples in Toronto myself, along with my wife and father-in-law; family in Calgary, Amanda and Catherine Wong graciously helped me to gather samples as well. Jules Blais and Linda Kimpe at the University of Ottawa, our partners in the project sampled from the Ottawa River. What we found is concentrations generally below what would be considered unsafe, below the eco-toxicity levels, at least as of the time samples were collected. This reflects that Canada has good wastewater treatment, some of the best connectivity in the world. We certainly detected compounds, I believe between ten and twenty, right in line with what we see in most US states and across Western Europe.
WT: What happens now, where does the report go? What do you hope people will do with this information?
Wilkinson: My hope, I would really like to make this a larger issue of the public consciousness. I would like people to know this is an issue, and that we are fortunate to have the solutions to fix most of it. Good sewage connectivity and very effective modern wastewater treatment are the keys to fixing this problem. The unfortunate thing is that these solutions are very expensive, and hard infrastructure to incorporate into as-built environments in much of the world. I have seen a number thrown around; 50 billion British pounds would be required to solve this in a few of the most populated cities in the world. So, funding is a serious impediment.
I hope we come at this with regulatory approaches as well. An example of a very fixable situation is Nairobi. The City of Nairobi does have some sewage connectivity, but most homes are using septic tanks. We found most of the sewage plants are over capacity, so septic trucks tend to dump in the closest river. They’re not meant to do that, but there’s no enforceable legislation preventing them. In my mind, this is one of the simplest fixes, enforceable regulatory changes.
We also have some new treatment processes that can be plugged into existing wastewater treatment facilities: activated carbon filtration for example and using UV light to break down the chemicals before they enter the effluent. These technologies are shown to be extremely effective, but also expensive.
I hope that the UN and local governments realize the extent of the problem and that it is fixable if enforceable regulation and investment in infrastructure are prioritized.
WT: You mentioned ultraviolet, is that the best technology to solve this? New nanotech is coming out every day, is there a place for nano-filtration?
Wilkinson: I like UV because it breaks down the molecules. There is an argument that sometimes the breakdown products can be more toxic than the original molecule itself. We just don’t know enough at the moment, to tell which molecules. In an ideal world, there would be a combination of treatments, based on the physical and chemical properties of the molecule. Some are more effectively removed or broken down by different treatment mechanisms.
The other issue is, activated carbon and nanofiltration, while effective, do not actually remove the molecules, they separate the compounds from the water, and then they have to be reclaimed, or cleaned off.
WT: Do you see yourself doing another study like this, or has three years been enough?
Wilkinson: We are definitely planning to do more. Bringing this into public consciousness, we envision a citizen science role, we want to look at how changes in seasons affect the concomitant risk, there are aspects of climate change we would like to test.
WT: How does climate change come into this?
Wilkinson: With weather patterns changing, some areas of the planet will become more water-scarce. Also with more population density, stress on the water system can reach worrying levels. There is more work to do.
WT: Thank you, John, this has been enlightening. I will end the interview there.