Date of Award

Spring 5-12-2018

Level of Access

Open-Access Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Earth Sciences

Advisor

Karl Kreutz

Second Committee Member

Jules Blais

Third Committee Member

Shaleen Jain

Additional Committee Members

Aaron Putnam

James Settele

Sean Birkel

Abstract

Pollutants released by industrialized nations between 1960 and 2004 have been transported northward through atmospheric processes and deposited into glaciated alpine ecosystems. Many of these chemicals retain their original structure and are absorbed into the biota thousands of miles away from where they were originally utilized. With a warming climate increasing the melt of alpine glaciers, these glaciers may be introducing growing amounts of toxins into the watershed. While studies have demonstrated the existence of resident pollutants within glaciated ecosystems, no one has developed a risk assessment to identify sources and quantity of risk posed by these compounds when released in glacial outflows. Therefore, the goal of this study is to develop a framework to assess the conditions under which glacial release of persistent organic pollutants are a risk to the health of downstream communities. The first section of our study utilizes ice core and meltwater records we measured at Jarvis Glacier, in the Interior of Alaska. Within interior Alaskan glaciers, our study was the first to identify pollutants, including DDT, DDE, DDD, α-HCH and ϒ-HCH concentrations using Solid-Phase Extraction (SPE) and Semi-Permeable Membrane Devices (SPMD). Subsequently, we developed a screening-level risk assessment model for pollution in glacial watersheds based upon the US Environmental Protection Agency (EPA) methodology which we apply to three unique case studies. With collaborators in Italy, Switzerland, and our own research in Alaska, we analyze varying chemicals, glacial regimes and uptake rates characteristic of each watershed to determine the potential risk to humans. We find that within all glacial systems studied potential human risk is determined by quantity of fish consumption and chemical toxicity based on chemical species. Chemicals with higher human toxicity and bioaccumulation rates, such as DDT and PCBs, are identified to have a greater long-term risk even at low levels. Our results imply that further investigation of an Organochlorine Pollutant (OCP) signal in glacial meltwater and fish throughout the North American Arctic and European Alps is warranted. Other glacial watersheds of a similar size and latitude may see similar risk, and our model can be applied broadly to other glaciated ecosystems.

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