Persistent organic pollutants (POPs) are globally distributed because they resist degradation in the environment and are highly susceptible to transport. They are typically hydrophobic, lipophilic compounds and thus, have a propensity to partition into the lipids in organisms and become stored in fatty tissues. This behavior leads to accumulation of POPs within, and magnification up, the food web. Elevated concentrations of POPs have been measured in wildlife and humans, and are a particular problem in Arctic regions. Negative impacts of POPs on wildlife and human health can include changes in eggshell thickness of birds of prey, reproductive impairment, endocrine disruption, and immune system damage of wildlife.
While it is generally accepted that persistent organic pollutants are relatively long-lived in the environment, processes that breakdown these chemicals have been observed. Thus, a question we hope to address is “How ‘persistent’ are persistent organic pollutants”? For example, photochemical (i.e. sunlight driven) breakdown of POPs in surface waters has been observed. Our interests are to better understand the processes that can affect the fate of organic pollutants in the environment and what products are formed from POP degradation. A portion of this work is focused on Arctic regions and the chemistry that can occur in snow and ice.
However, these chemicals also are important at lower latitudes … i.e. where a majority of the population resides. Thus, a portion of our studies will focus on the mid-latitude chemistry that can lead to the degradation of pollutants in surface waters. Specifically we will focus on photochemical processes that can lead to pollutant degradation in local surface waters. The synergistic effects of metals, dissolved organic matter, pH, and microbial processes will be evaluated as well.
Why Should We Care???
Persistent organic pollutants have potentially toxic effects to humans and wildlife. While it is generally accepted that persistent organic pollutants are relatively long-lived in the environment, processes that breakdown these chemicals have been observed. To best understand how POPs can affect the environment and living organisms, we need to understand the cycling and ultimate fate of these compounds.
Our research activities include laboratory and field experiments to:
- determine the photochemical behavior of a variety of pollutants in local waterways
- determine if other chemicals present (like natural organic matter) can affect pollutant degradation
- determine what products are produced and if the toxicity of these compounds increase relative to the parent pollutant
The initial targets of this project will include priority pollutants that have been found in appreciable levels in local waterways. These include pesticides, herbicides, and pharmaceuticals.