Increased use of sanitizers and disinfectants during the COVID-19 pandemic: identification of antimicrobial chemicals and considerations for aquatic environmental contamination

In response to the coronavirus (COVID-19) pandemic, there has been an increased need for personal and environmental decontamination to aid in curbing transmission of the SARS-CoV-2 virus. Products used for this purpose include sanitizers for hands and disinfectants for surfaces. The active chemical ingredients used in these products, termed antimicrobials, can enter waste streams after application and may be emerging as more prominent environmental contaminants. Even prior to COVID19, there was recognized need to examine their implications for aquatic biota, which is now made more pressing due to their exaggerated use in response to the pandemic. Our objectives were to identify current antimicrobial active ingredients, quantify their increased use, and determine which may be candidates for further consideration as possible aquatic contaminants. By consulting multiple sources of publicly available information in Canada, we identified current-use antimicrobials from the lists of sanitizers and surface disinfectants approved for use against SARS-CoV-2 by Health Canada and the drug registration database. To estimate the use of sanitizers and disinfectants, we evaluated import quantities and grocery store retail sales of related compounds and products (Statistics Canada) and both lines of evidence supported increased use trends. The list of identified antimicrobials was refined to include only candidates with potential to reach aquatic ecosystems, and information on their environmental concentrations and toxicity to aquatic biota was reviewed. Candidate antimicrobials (n = 32) fell into four main categories: quaternary ammonium compounds (QACs), phenols, acids, and salts. Benzalkonium chloride, a QAC, was the most prominent active ingredient used in both nonalcohol-based hand sanitizers and surface disinfectants. Four QACs followed in prevalence and the next most used antimicrobial was triclosan (hand sanitizers only), an established and regulated environmental contaminant. Little information was found on environmental concentrations of other candidates, suggesting that the majority would fall into the category of emerging contaminants if they enter aquatic systems. Several were classified as acutely or chronically toxic to aquatic biota (Globally Harmonized System), and thus we recommend empirical research begin focusing on environmental monitoring of all candidate antimicrobials as a critical next step, with detection method development first where needed.

Social–ecological systems approaches are essential for understanding and responding to the complex impacts of COVID-19 on people and the environment

The Coronavirus Disease 2019 (COVID-19) pandemic is dramatically impacting planetary and human societal systems that are inseparably linked. Zoonotic diseases like COVID-19 expose how human well-being is inextricably interconnected with the environment and to other converging (human driven) social–ecological crises, such as the dramatic losses of biodiversity, land use change, and climate change. We argue that COVID-19 is itself a social–ecological crisis, but responses so far have not been inclusive of ecological resiliency, in part because the "Anthropause” metaphor has created an unrealistic sense of comfort that excuses inaction. Anthropause narratives belie the fact that resource extraction has continued during the pandemic and that business-as-usual continues to cause widespread ecosystem degradation that requires immediate policy attention. In some cases, COVID-19 policy measures further contributed to the problem such as reducing environmental taxes or regulatory enforcement. While some social–ecological systems (SES) are experiencing reduced impacts, others are experiencing what we term an "Anthrocrush,” with more visitors and intensified use. The varied causes and impacts of the pandemic can be better understood with a social–ecological lens. Social–ecological insights are necessary to plan and build the resilience needed to tackle the pandemic and future social–ecological crises. If we as a society are serious about building back better from the pandemic, we must embrace a set of research and policy responses informed by SES thinking.

COVID-19 reduced recreational fishing effort during the black bass spawning season, resulting in increases in black bass reproductive success and annual recruitment

In Opinicon Lake, Ontario during two non-pandemic years (2019 and 2022) the hook-wounding rates from recreational angling observed among nesting male largemouth bass Micropterus salmoides (LMB), and nesting male smallmouth bass Micropterus dolomieu (SMB), were quite high, but typical of those observed in the lake over the last 20 years of monitoring. That level of illegal, preseason angling resulted in very low percentages of both LMB and SMB nesting males being successful at raising their broods to independence, rates comparable to those observed for this lake in previous years. In 2020 and 2021, amid the COVID-19 pandemic, however, access to fishing in Ontario was severely limited during the bass spawning season, which serendipitously provided a natural “whole-lake bass spawning sanctuary” to study. Not surprisingly, the hook-wounding rates for nesting male LMB and SMB in Opinicon Lake were the lowest rates ever observed over the last 30 + years. Concomitantly, the percentage of nesting male LMB and SMB that were successful at raising their broods to independence was approximately 3–4 times greater than that in the non-COVID years. Not unexpectedly, those increases in nesting success translated to similar increases in LMB and SMB reproductive success (production of post parental care, independent fry). More importantly, those increases further resulted in large increases in the annual recruitment of both LMB and SMB. This unanticipated COVID-driven experiment revealed that using bass spawning sanctuaries would be more efficient than closed seasons as a management strategy to conserve levels of black bass annual recruitment.

Global COVID-19 lockdown highlights humans as both threats and custodians of the environment.

The global lockdown to mitigate COVID-19 pandemic health risks has altered human interactions with nature. Here, we report immediate impacts of changes in human activities on wildlife and environmental threats during the early lockdown months of 2020, based on 877 qualitative reports and 332 quantitative assessments from 89 different studies. Hundreds of reports of unusual species observations from around the world suggest that animals quickly responded to the reductions in human presence. However, negative effects of lockdown on conservation also emerged, as confinement resulted in some park officials being unable to perform conservation, restoration and enforcement tasks, resulting in local increases in illegal activities such as hunting. Overall, there is a complex mixture of positive and negative effects of the pandemic lockdown on nature, all of which have the potential to lead to cascading responses which in turn impact wildlife and nature conservation. While the net effect of the lockdown will need to be assessed over years as data becomes available and persistent effects emerge, immediate responses were detected across the world. Thus, initial qualitative and quantitative data arising from this serendipitous global quasi-experimental perturbation highlights the dual role that humans play in threatening and protecting species and ecosystems. Pathways to favorably tilt this delicate balance include reducing impacts and increasing conservation effectiveness.

Ten principles for generating accessible and useable COVID-19 environmental science and a fit-for-purpose evidence base

Abstract 1. The ?anthropause?, a period of unusually reduced human activity and mobility due to COVID-19 restrictions, has serendipitously opened up unique opportunities for research on how human activities impact the environment. 2. In the field of health, COVID-19 research has led to concerns about the quality of research papers and the underlying research and publication processes due to accelerated peer review and publication schedules, increases in pre-prints and retractions. 3. In the field of environmental science, framing the pandemic and associated global lockdowns as an unplanned global human confinement experiment with urgency should raise the same concerns about the rigorousness and integrity of the scientific process. Furthermore, the recognition of an ?infodemic?, an unprecedented explosion of research, risks research waste and duplication of effort, although how information is used is as important as the quality of evidence. This highlights the need for an evidence base that is easy to find and use ? that is discoverable, curated, synthesizable, synthesized. 4. We put forward a list of 10 key principles to support the establishment of a reproducible, replicable, robust, rigorous, timely and synthesizable COVID-19 environmental evidence base that avoids research waste and is resilient to the pressures to publish urgently. These principles focus on engaging relevant actors (e.g. local communities, rightsholders) in research design and production, statistical power, collaborations, evidence synthesis, research registries and protocols, open science and transparency, data hygiene (cleanliness) and integrity, peer review transparency, standardized keywords and controlled vocabularies.

Conservation physiology and the COVID-19 pandemic.

The COVID-19 pandemic and associated public health measures have had unanticipated effects on ecosystems and biodiversity. Conservation physiology and its mechanistic underpinnings are well positioned to generate robust data to inform the extent to which the Anthropause has benefited biodiversity through alterations in disturbance-, pollution- and climate change-related emissions. The conservation physiology toolbox includes sensitive biomarkers and tools that can be used both retroactively (e.g. to reconstruct stress in wildlife before, during and after lockdown measures) and proactively (e.g. future viral waves) to understand the physiological consequences of the pandemic. The pandemic has also created new risks to ecosystems and biodiversity through extensive use of various antimicrobial products (e.g. hand cleansers, sprays) and plastic medical waste. Conservation physiology can be used to identify regulatory thresholds for those products. Moreover, given that COVID-19 is zoonotic, there is also opportunity for conservation physiologists to work closely with experts in conservation medicine and human health on strategies that will reduce the likelihood of future pandemics (e.g. what conditions enable disease development and pathogen transfer) while embracing the One Health concept. The conservation physiology community has also been impacted directly by COVID-19 with interruptions in research, training and networking (e.g. conferences). Because this is a nascent discipline, it will be particularly important to support early career researchers and ensure that there are recruitment pathways for the next generation of conservation physiologists while creating a diverse and inclusive community. We remain hopeful for the future and in particular the ability of the conservation physiology community to deliver relevant, solutions-oriented science to guide decision makers particularly during the important post-COVID transition and economic recovery.

A Global Perspective on the Influence of the COVID-19 Pandemic on Freshwater Fish Biodiversity

The COVID-19 global pandemic and resulting effects on the economy and society (e.g., sheltering-in-place, alterations in transportation, changes in consumer behaviour, loss of employment) have yielded some benefits and risks to biodiversity. Here, we considered the ways the COVID-19 pandemic has influenced (or may influence) freshwater fish biodiversity (e.g., richness, abundance). In many cases, we could only consider potential impacts using documented examples (often from the media) of likely changes, because anecdotal observations are still emerging and data-driven studies are yet to be completed or even undertaken. We evaluated the potential for the pandemic to either mitigate or amplify widely acknowledged, pre-existing threats to freshwater fish biodiversity (i.e., invasive species, pollution, fragmentation, flow alteration, habitat loss and alteration, climate change, exploitation). Indeed, we identified examples spanning the extremes of positive and negative outcomes for almost all known threats. We also considered the pandemic’s impact on freshwater fisheries demand, assessment, research, compliance monitoring, and management interventions (e.g., restoration), with disruptions being experienced in all domains. Importantly, we provide a forward-looking synthesis that considers the potential mechanisms and pathways by which the consequences of the pandemic may positively and negatively impact freshwater fishes over the longer term. We conclude with a candid assessment of the current management and policy responses and the extent to which they ensure freshwater fish populations and biodiversity are conserved for human and aquatic ecosystem benefits in perpetuity.