Polycyclic aromatic compounds in Canadian Arctic seabirds: Spatial and temporal trends.

Area of Science:

• Environmental Science
• Ecotoxicology
• Arctic Research

Background:

• The Canadian Arctic faces environmental shifts due to climate change, leading to reduced sea ice and increased industrial activities like shipping and mining.
• This heightened activity, alongside natural oil seeps, raises concerns about oil and gas contamination in sensitive Arctic ecosystems.
• Polycyclic aromatic compounds (PACs) are persistent, bioaccumulative, and toxic organic contaminants linked to oil and gas, posing risks to wildlife.

Purpose of the Study:

• To examine spatial and temporal trends of PACs in thick-billed murre eggs from high and low Arctic locations in Nunavut.
• To assess the suitability of seabird eggs as a sentinel system for monitoring PAC contamination in the Arctic.

Main Methods:

• Quantified 48 polycyclic aromatic hydrocarbons (PAHs) and alkylated polycyclic aromatic hydrocarbons (APAHs) in murre eggs collected between 1993 and 2024.
• Utilized gas chromatography-tandem mass spectrometry for precise contaminant analysis.
• Compared PAC concentrations between high Arctic (Prince Leopold Island) and low Arctic (Coats Island) populations.

Main Results:

• Overall concentrations of total PACs, alkylated high molecular weight (AHMW) PACs, and high molecular weight (HMW) PACs were higher in eggs from the high Arctic compared to the low Arctic.
• PAC concentrations did not show dramatic changes over the study period (1993-2024) at either location, but significant year-to-year variations were observed.
• Results suggest spatial differences in PAC exposure between the high and low Arctic regions.

Conclusions:

• Thick-billed murre eggs serve as a valuable indicator for monitoring PAC contamination in the Canadian Arctic.
• Despite stable overall trends, observed annual variations in PACs warrant continued surveillance.
• Monitoring PACs in seabird eggs can help assess risks to Arctic wildlife and ecosystems amid growing industrial pressures.