Understanding the consequences of exposure to pharmaceutical pollutants and wastewater effluents for aquatic wildlife

Over the past 50 years, human production and consumption of synthetic chemicals like pharmaceuticals has sky rocketed. We might not always think about how our use pharmaceuticals can be connected to the environment, but many of the drugs we consume can indeed find their way back to rivers, lakes, and streams. This is because the dose you consume is not fully absorbed by your body before being excreted, and unfortunately conventional wastewater treatment processes are not fully equipped to remove these compounds form the wastewater that they treat. This means that pharmaceuticals are a relatively new type of environmental pollutant that are now entering aquatic environments around the world.

In my docent talk, I will explain the environmental issue of pharmaceutical pollution and go through several of my recent studies that have sought to better understand the ultimate impacts of pharmaceuticals in the environment for freshwater organisms. Although much knowledge has been gained over the last two decades on the how pharmaceuticals can impact aquatic animals like fish, much of the work here has been constrained to studying individual level responses in highly artificial laboratory environments. In the first part of my talk, I will present research on how using larger spatial scales (e.g., running studies in natural lakes) and more realistic, and complex social environments with multiple individuals can allow us to better link exposure to pharmaceutical pollutants with ultimate outcomes for organisms like survival and reproductive success. These studies are focused on the impacts of specific psychiatric pharmaceuticals (e.g., anti-anxiety medications, antidepressants) that are commonly measured in Swedish surface waters.

As previously mentioned, the main source of pharmaceuticals in aquatic environments is from wastewater treatment plant effluents. Therefore, another focus of my research seeks to understand how wastewater treatment plant effluents themselves—and the complex mixture of pollutants within them—shape aquatic communities and biodiversity. Here, I will present current and planned future research focused on how wastewater effluents affect aquatic organism behaviour, habitat choice, and biodiversity using a combination of field and laboratory experiments. I will relate this to options for upgrading wastewater treatment technologies that can help reduce pharmaceutical pollution, and potentially improve freshwater habitats receiving wastewater effluents.