Plastic pollution has become a hallmark of the modern world. Its persistence in the form of smaller microplastic particles (<5 mm) lends itself to dissemination across the planet, namely in aquatic and terrestrial environments. Despite this ubiquity, characterization of the fate of microplastics in Canadian environments is still in its infancy, and ecotoxicological data is often reliant on primary microplastics and model organisms. In addition, microplastics are a diverse suite of contaminants, whose size, polymer, associated additives and morphology will affect how they are transported, and how they interact with biota in both aquatic and terrestrial environments. Our goal with this session is to bring together microplastic researchers from different fields to highlight how fate, effects and exposure data can be utilized to inform management strategies and discuss where the future of microplastic research should be directed.

Coastal zones are home to a diverse range of marine life and are at increased risk of exposure to both anthropogenic contaminants and environmental stressors. In coastal habitats effluents from wastewater and industry merge with the presence of harbors, marinas, fisheries, and rivers’ outlets, facilitating the transport and accumulation of additional anthropogenic-derived pollutants. Assessing the potential effect of these environmental contaminants - such as pesticides, plastics, PAHs, dioxins, PFAS, pharmaceuticals, and personal care products - on coastal organisms is of extreme importance.

In addition to chemical threats, coastal environments are among the most sensitive areas to climate change. Therefore, marine coastal organisms face additional environmental stressors, with possible additive, synergistic or antagonistic effects. The stress posed by phenomena such as marine heat waves, acidification, and hypoxia appears to strongly modulate the accumulation and toxicological effects of contaminants.

This Session welcomes contributions on the effects of emerging contaminants and/or climate change on marine organisms (vertebrates, invertebrates, plants, microalgae), utilizing novel methods from in vitro to in vivo studies. In keeping with this year’s CEW theme, we encourage submissions dealing with investigation of cause studies, integration of multi-stressors, and implementation of remedial action plans.

Canada holds vast mineral resources that are in increasing demand, notably due to their use in low-carbon technologies (e.g. electric vehicle batteries). Over the past decade, important markets have emerged for metals whose ecotoxicity remains poorly understood (e.g. platinum group metals). An environmentally responsible exploitation of these resources requires sound scientific understanding of their fate and potential effects in natural ecosystems.

The goal of this session is to bring together scientists from different sectors and expertise, to discuss recent developments in metal environmental chemistry and toxicology, that will help address existing and emerging challenges related to metal contamination. We invite contributions on the fate and effects of metals under varying environmental conditions (e.g. varying salinity, pH), multi-stress scenarios (e.g. metal x heat stress), metal mixtures toxicity, new mechanistic understanding of metal uptake and toxicity, as well as on emerging methods for assessing metal exposure and toxicity (e.g. metabolomics, genomics). We particularly encourage contributions on emerging metals of concerns, on long-term (chronic) toxicity, and on the incorporation of science-based concepts into environmental risk assessment frameworks (e.g. metal bioavailability approaches).

Tire and road wear particles (TRWPs) contain a complex mixture of substances which enter the atmosphere as well as terrestrial and aquatic systems, making them a growing global concern. One of these substances, 6PPD-quinone, a transformation product of the common tire antioxidant 6PPD, is lethal to coho salmon and some other salmonids at environmentally relevant concentrations. The discovery of this contaminant put a spotlight on this group of pollutants, and research is rapidly developing on the refinement of analytical methods and environmental monitoring, as well as on the ecotoxicological effects and mechanisms of action. For this session, we invite contributions in any of these research areas, as well as presentations relating to regulatory activities or environmental mitigation and remediation strategies. Within scope are not only presentations focused on 6PPD-quinone but also on TRWPs more broadly, other tire-rubber-derived substances and their transformation products. This session will be aimed towards presenting the current state-of-the-science, fostering collaboration between Canadian researchers, and bridging science and policy.

Laboratory-based ecotoxicity test methods using representative taxa are developed and validated by researchers and standardization organizations (e.g., ECCC, USEPA, OECD). Data from these methods are used in applications including environmental monitoring, risk assessments, regulatory frameworks, and contaminated site management. There is a growing interest to include underrepresented taxa and new technologies/biological endpoints rather than traditional endpoints (survival, growth, reproduction) in these applications, which has led to new method development. The first part of this session will focus on innovative approaches for assessing the toxicity of complex mixtures or contaminants of concern in aquatic media (freshwater, saltwater, sediment). Novel methodologies and applications of ecologically relevant single-species tests are of particular interest, as well as alternative endpoints (e.g., biochemical/physiological measurements, behaviour, development, endocrine disruption), cell lines, and ‘omics. The second part of this session will focus on issues related to the application of novel and existing standardized test methods and the interpretation of results in an environmentally relevant context. Many ecotoxicity studies are performed in controlled laboratory conditions following standardized guidelines, removing many factors from experiments that could influence an organism’s sensitivity and applicability of data to real-world environments. Studies that go beyond standardized laboratory testing by comparing data generated from these methods to those with additional environmental relevance (e.g. seasonal changes, multiple stressors, wild species) are of particular interest. By understanding what current standardized methods are missing, we can adapt risk assessment practices to utilize novel methods, improving the environmental relevance and applicability of ecotoxicity research.

Biosolids are the stabilized solid organic materials that remain after the treatment of wastewater at municipal wastewater treatment plants (WWTPs). Biosolids are treated to meet specific standards and requirements and are frequently applied as a fertilizer to agricultural land. This government regulated practice has many benefits including recycling beneficial plant nutrients, offsetting rising synthetic fertilizer prices, and diverting waste away from landfills. Although WWTPs do not produce or use emerging contaminants themselves, biosolids can contain these substances due to their widespread use by society. Biosolids use as an agricultural fertilizer has recently received a lot of attention particularly due to per- and polyfluoroalkyl substances (PFAS) in the US at locations impacted by large industrial sources. Additionally, biosolids are known to contain other emerging contaminants such as microplastics, pharmaceutical and personal care products (PPCPs), and known endocrine disrupting chemicals (EDCs). However, the risk associated with emerging contaminants in biosolids in Canada is not well known. The goals/objectives of this session are to discuss advancements in the techniques and approaches to characterize emerging contaminants present in Canadian biosolids, measure concentrations, and to assess risk. 

Digital technologies shape the way we work, and these technologies are progressing rapidly now more than ever. This session focusses on the ‘Charting the Future’ component of this year’s CEW theme, providing a platform to share and discuss how the latest trends in digital technology are interacting with our profession. Our goal is to showcase innovative digital technology and its applications in aquatic science, presenting case studies demonstrating how digital tools improve workflows, efficiency, and precision in assessing, monitoring, and managing aquatic environments. Further, this platform will provide an opportunity to discuss the responsible use of such tools in the workplace (e.g., generative AI). The target audience for this session includes researchers, practitioners, and policymakers in aquatic science and related fields, who use digital tools to manage, analyse, visualize, and share data in desktop and field environments.

Canada is one of a few countries actively involved in the full nuclear fuel cycle, which includes uranium mining and milling, fuel refining and fabrication, nuclear power generation, medical isotope production and associated waste management. Canada has also committed to the development of small modular nuclear reactors, as a means of reducing greenhouse gas emissions, while providing grid-scale electricity generation and non-grid heat and electricity for heavy industry and remote communities. This fuel cycle produces by-products and Canadian regulations require their safe management. Many of the same radionuclides associated with the nuclear fuel cycle are also released by a number of other industries, such as the extraction/processing of non-uranium ores (thorium, rare earth elements, niobium, phosphates, base metals), oil and gas production, and the mining and combustion of coal.

Due to potential ecological risks from radiological exposure, furthering research is critical to science-based decision making to protect both people and the environment. This includes characterization of natural background radioactivity, as well as the transport and behaviour of anthropogenic and naturally occurring radionuclides in the environment. The goal of this session is to provide a venue for Canadian researchers, regulators, and industry representatives to share their research and other advances in radiological environmental fate and effects characterization and ecological risk assessment. The session serves as an opportunity to exchange lessons learned among the ecotoxicological, and radiological research and regulatory communities. In addition to the diverse topics described above, we particularly invite contributions that cover:

· Adverse Outcome Pathways modelling to structuring future radiological research;

· Research in support of new environmental quality guidelines derivation;

· Environmental fate and effects of radionuclides and incorporation into the regulatory framework; and

· Radiological risk assessment and accompanying field studies.

Due to anthropogenic impacts, variable aquatic temperatures have become a concern for aquatic species. Temperature changes may lead to perturbations in animal responses to stressors, including in the wake of contaminant exposure. Environmental temperature influences uptake metabolism, or responsiveness to toxicants, impairing physiological systems and subsequently the development, fitness, and possibly survival of aquatic life. There is still a considerable knowledge gap in the effects of variable temperature on aquatic species, but our understanding of its combination with organic (e.g., pharmaceuticals, pesticides, and industrial by-products), and inorganic (e.g., nitrite, lead, and copper) chemicals of emerging concern is still in its infancy. Knowledge in these pertinent topics may help develop risk assessment strategies for species at risk, and invasive aquatic species, in the face of unpredictable ambient temperatures and increasing contaminant load. 

In this session, we welcome studies that consider the effects of temperature, or the combined effects of temperature and contaminants on aquatic species. Studies with multiple stressors throughout development, that characterize anthropogenic impacts on energetic performance (aerobic scope, cardiac function, mitochondrial function, energetic stores), or that focus on the capacity of animals to withstand temperature increases are particularly welcome.

This session will highlight recent advances in Wildlife Toxicology, bringing together scientists who primarily study wildlife in the natural environment with those working in the laboratory. The session welcomes presentations on all emerging techniques and their applications to assessing impacts of environmental contaminants on wildlife health. This would include, but is not limited to, new approaches for tracking and monitoring wildlife, non-targeted screening methods for chemical analysis, and application of ‘omics technologies (e.g., genomics, transcriptomics, metabolomics etc.) to non-model species. Presentations on all organisms including fish and invertebrates are welcome. Ultimately, this session offers a platform for interdisciplinary exchange, fostering collaboration and addressing the complex challenges facing the study of wildlife toxicology.

Like other wildlife, many of Canada’s over 800 Species at Risk (SAR; including arthropods, molluscs, fish, amphibians, reptiles, birds, and mammals) are exposed to environmental contaminants introduced intentionally or as by-products of agriculture, oil and gas production, manufacturing and other industries. Many such contaminants, including metals, plastics, and organic compounds such as pesticides, pharmaceuticals and polycyclic aromatic hydrocarbons, can have direct or indirect physiological or behavioural effects on wildlife including mortality, endocrine disruption, immunosuppression, and increased susceptibility to disease. Relative to other wildlife species however, risk to SAR of population-level effects, including viability, from exposure to environmental contaminants may be higher given their limited population sizes, growth rates, and geographic distributions. Moreover, data on exposure and effects of contaminants on SAR are generally lacking, due to their rarity and challenges involved in sampling tissue and/or conducting laboratory studies. Therefore, other tools are needed to study potential impacts of contaminants on SAR: environmental sampling and non-invasive sampling to assess exposure; proxy species to identify mechanisms of action and individual health effects; and modeling to predict potential population-level effects. This session invites contributions from scientists working on any aspect of risk, exposure, or effects of environmental contaminants on SAR, with a special focus on challenges, opportunities and novel solutions.

Over the past five decades, the history of CEW has been intricately linked to our evolving understanding of the environmental risks associated with wastewater effluents. During this time, we have witnessed significant developments in treatment technologies and management strategies aimed at minimizing these risks. The early work on nutrients, or the later recognition of the environmental risks posed by endocrine disruptors are clear examples of keystone research on our past, however, the challenges persist, as we confront an ever-growing list of contaminants of emerging concern (CECs) including pharmaceuticals, personal care products, or microplastics.

In this session we will delve into the past, exploring the milestones that shaped our understanding of wastewater-related environmental risks. However, our focus extends beyond history. We aim to engage researchers and practitioners in a dialogue about the present and future. This session will cover a range of topics, including the latest advances in detection, monitoring, and effect assessment of wastewater-associated contaminants in WWTPs, their effluents, and receiving ecosystems. We also welcome recent research on the mechanisms of toxicity of these chemicals, and the potential effects of mixtures. Additionally, we welcome research that address effects of CECs on aspects related to ecosystem functioning, such as effects on nutrient cycling, microbial communities, and food webs. 

The proposed session will explore the environmental fate of agrochemicals, including the transport, degradation, and persistence of pesticides in various ecosystems. We will delve into the mechanisms by which these substances enter and affect terrestrial and aquatic environments, with a focus on the latest research findings and methodological advancements in tracing and modeling their distribution, with a spotlight on water monitoring. Furthermore, the session will address the ecotoxicological effects of both pesticides and nutrients when they exceed their intended targets and enter the broader environment. We will examine the direct and indirect consequences on non-target species, including beneficial insects, wildlife, and aquatic organisms. Case studies highlighting the sub-lethal and chronic effects of exposure, as well as the potential for bioaccumulation and biomagnification, will be presented. Interactive discussions will aim to bridge the gap between current agricultural practices and sustainable strategies, considering the balance between crop productivity and environmental protection such as recent emergences in research on various pollinator species. The session will also provide a platform for the presentation of innovative approaches to characterize and potentially mitigate the adverse effects of agricultural pollutants, such as the development of biological pesticides and precision farming techniques. Cumulative risk assessment and mechanistic research implicating common biological pathways and species at risk research are encouraged. By fostering a collaborative dialogue, this session intends to contribute to the development of integrated pest and nutrient management practices that safeguard both agricultural productivity and ecological integrity.

As the global demand for critical and strategic minerals increases, federal and provincial jurisdictions with significant mineral resources are developing strategies to ensure the supply of these minerals for the development of advanced technologies. There is, however, a lack of the ecotoxicological data needed to assess and manage the environmental impacts of activities such as extraction, processing, and recycling of critical minerals. This session invites submissions presenting studies of the ecotoxicological impacts of data poor elements such as lithium, rare earth element, platinum group elements, niobium, and vanadium on aquatic and terrestrial ecosystems. To assess the environmental impact of these data poor elements, submissions focussing on a wide range of topics including, the sources, fate, exposure and effect relationships, and mechanisms of toxicity at molecular, cellular, individual, population and community levels are encouraged. The goal of this session is to provide a space to communicate recent information on adverse effects essential to establishing environmental quality guidelines, but also provide insight that can guide further testing and research needs. Researchers, policymakers, and industry professionals are encouraged to participate in this session for a comprehensive presentation of the state-of-the-art in our understanding the environmental impact of the entire value chain for critical and strategic minerals.

In recent years, research involving Environmental DNA (eDNA) and its integration into monitoring programs has increased dramatically.  This technology has many applications in supporting the non-invasive assessment of ecosystem health including the identification of invasive species, detection of sensitive or cryptic species, and determination of biodiversity and community structure. Despite this, a great deal of research is needed for the interpretation of eDNA observations supporting conservation and ecosystem management decisions.  Presentations invited into this session will address knowledge and research gaps into issues addressing: 1) How to interpret eDNA detection in relation to traditional field observation techniques; 2) Optimization of collection and laboratory practices to detect and reduce contamination, signal inhibition, degradation, etc.; 3) Determining what is still needed to understand the ecology of eDNA that influences its distribution, persistence, and degradation; 4) Establishing when it is appropriate to use targeted species-specific assays versus metabarcoding approaches; 5) Which are the most appropriate pipelines, combination of bioinformatics techniques, and reference databases for particular groups of taxa to balance community coverage versus certainty of detection. Discussions in this session will be encouraged toward building a community of knowledge and practice to further identify and address knowledge and research gaps; and 6) How can the use of eDNA address initiatives to develop New Approach Methods (NAMs) to reduce the use of animals in research?

Environments adjacent to mining operations are the focus of a wide range of chemical and biological monitoring, toxicity testing, and research studies. This includes studies to meet regulatory requirements (e.g., Environmental Effects Monitoring required under the Metal and Diamond Mining Effluent Regulations), baseline monitoring to inform environmental assessments, monitoring required under various permit conditions, remediation and reclamation, community-based monitoring programs, and academic research. The session could include presentations on a range of topics including study designs, results and interpretation of monitoring studies, new developments in toxicity testing and environmental monitoring, regulatory requirements, community-led monitoring, and integration of Indigenous knowledge. The session could also include presentations on monitoring in the terrestrial environment, ranging from bats in closed mines, to caribou and other large mammals, to studies of metals uptake in vegetation. The goal of the session is to provide an opportunity to share new, emerging, or innovative monitoring methods and research for aquatic and terrestrial environments of relevance to mining, share perspectives on mining-related environmental monitoring requirements, and explore the interface between environmental monitoring and Indigenous knowledge in the context of mining. The target audience spans all sectors including government, stakeholders/rights-holders, consulting, industry, and academics.

This session provides an opportunity to present work that does not naturally fit in any of the other proposed sessions. Research related to soil, sediment, air, terrestrial, and aquatic ecosystems, at all levels of biological organization, and all contaminant classes are welcome.