Nontarget analysis of Arctic sediments: An empirical indicator of persistent chemicals overlooked by regulation

The increasing volume and type of chemicals produced worldwide every year have the potential to cause severe ecosystem and human health problems.

However, due to largely insufficient information regarding the identities, properties, and emissions of these substances, it is challenging to obtain a complete picture of global chemical pollution to aid in development and implementation of effective regulations.

Despite the Arctic being pristine and distantly isolated from human activities, Arctic sediments function as a receptor for contaminants that are transported over long distances.

Being ubiquitous far away from sources and in the Arctic requires that a chemical is sufficiently persistent, amenable to long-range transport (LRT), and produced in reasonably large quantities.

Therefore, it is hypothesized that Arctic sediments can serve as a natural indicator to identify flaws or inefficiencies in current chemical legislation and prioritize persistent chemicals that require further regulation.

The overarching aim of this project is to use state-of-the-art mass spectrometric tools together with high Arctic sediments to identify persistent contaminants of global concern, and then apply advanced statistical and modeling approaches to further understand their emission sources and LRT.

This analysis will be used to: (a) Prioritize persistent contaminants of emerging concern based on increasing temporal trends recorded in dated sediment cores; (b) Identify major emission regions by analyzing the spatial heterogeneity of contaminants among circum-Arctic shelf surface sediments; (c) Identify dominant LRT pathways by comparing the chemical compositions of Arctic lake sites affected solely by atmospheric LRT versus marine sites impacted by mixed pathways.

Results of this project will generate new knowledge on emission sources and transport of persistent chemicals of global concern while providing scientific guidance to improve chemical management and regulation policies.