Global climate change presents a unique problem in that the poles (i.e., Arctic and Antarctic) are warming at an accelerated rate compared to more temperate latitudes. As a consequence, permafrost in Arctic regions is softening, and sea ice coverage is declining, allowing for increased shipping activities, oil and gas extraction, mineral mining, and tourism, all with the potential to release contaminants into the environment. Cambridge Bay and Port Iqaluit are particularly susceptible to increased metal contaminants from intensified mineral extraction in these areas and oil-based contaminants from increased shipping traffic and vessel movement. Furthermore, the use of low-sulfur fuels is becoming more common in the Arctic to reduce air pollution from these increased activities. However, these newer fuels have different chemical properties, and their effects on cold-adapted Arctic organisms are not well understood. In addition, current water quality guidelines are based on sensitivities of animals from more temperate latitudes. As a result, these guidelines do not account for the specific environmental factors associated with cold water environments and ecosystems, nor reflect the sensitivity of Arctic species to pollutants. Therefore, we want to improve protocols to protect Northern ecosystems from human-associated disturbances. This research aims to find out whether or not Arctic species are more sensitive to pollutants than the temperate species currently used to set water quality standards. By doing so, we hope to develop better guidelines that specifically protect Arctic environments.This project aims to understand Arctic organisms' sensitivity to two types of toxicants: metal contaminants (copper, zinc, cobalt, nickel, and lithium) and oil-related chemicals (including perfluoroalkyl and polyfluoroalkyl substances (PFAS) and other substances from low-sulfur fuels). We will expose three types of organisms found in the Arctic to these toxicants of interest using Arctic-relevant concentrations under Arctic-relevant conditions (e.g., temperature, water chemistry). By testing different concentrations of exposure, we aim to identify the most vulnerable species and expand our knowledge to help communities, stakeholders, and policy-makers protect the Arctic environment. Sea-ice algae, copepods, and Daphnia (water fleas) will be collected in and around Cambridge Bay, NT. Specifically, algae and copepods will be collected in May 2025 from the sea ice between Cambridge Bay and the Dease Strait, while Daphnia and water samples will be collected in August from Greiner Lake. The exposures in May will last three weeks, while those in August will take five weeks. All experiments will be safely contained within CHARS labs, and water used in tests will be treated before disposal to remove any harmful substances. Different cleaning methods, such as biochar filtration, chelating resins, and activated charcoal, will be used to remove metals and chemicals, ensuring that no potentially harmful contaminants are released into the environment during the research project. After the exposures have been completed, the organisms will be shipped back to Quebec City (Institut national de la recherche scientifique; INRS) and/or Edmonton (University of Alberta) for further studies to look at how these contaminants build up over time and affect Arctic organisms over more extended time frames.This fieldwork is part of a 3-year NSERC Alliance grant and a 3-year DFO grant; throughout the tenure of the grant, community engagement will occur to communicate our research with the residents of Cambridge Bay. The project team will conduct community meetings and presentations each year of the project. These events will include demonstrations of the equipment used in the proposed studies as well as updates on the research project outcomes and information about the current status and policy surrounding critical minerals. During our field sampling, we plan on having a member of the local hunters and trappers organization (HTO) with us to make sure that we are supporting the local community while also learning directly from community members. Finally, we plan on participating in community feasts with the local HTO to build further connections with the local indigenous community.