Evidence on the effects of Flame Retardant substances at ecologically relevant endpoints: A Systematic Map Protocol

Background: Flame retardants are a diverse group of chemical substances that are widely used in products, such as furniture, textiles, electronics and building materials, to prevent or slow the development of fire. Flame retardant (FR) substances are known to pose a risk to human and environmental health, with complex and wide-ranging pathways of exposure and contamination. Once released into the environment, some FR substances are known, or predicted to have direct and indirect effects on long term survival, development, physiology and behaviour across a range of species, including humans and wildlife. Over time, FR substances have become the focus of many environmental and (human) health risk assessments. A list of potential FR substances has been developed (i.e. Bevington et al., 2022) however, detailed information on the risk, or hazard of such substances to human, animal and environmental health has not yet been collated. Systematic Evidence Maps (SEMs) have been identified as an underutilised tool for chemical risk assessment. They provide a core and reliable approach to evidence-based toxicology, which is informed by engagement with expert stakeholders, and based on the PECO (Population, Exposure, Comparator, Outcome) approach to question formulation (Morgan et al., 2018). The goal of this systematic evidence map is to identify, organise and map the available evidence on the (eco)toxicological effects of FR substances across ecologically relevant endpoints. 

Methods: We will search several electronic academic (PubMed, Web of Science, Google Scholar) databases, in addition to grey literature sites (OpenGrey) for existing evidence on the (eco)toxicological effect of FR substances to the environment. Eligible studies must contain primary research investigating the risk (or hazard) of one or more FR substances (as listed in Bevington et al., 2022) and study an ecologically relevant adverse effect, outcome and/or endpoint. Ecologically relevant effects include impacts on growth, development, survival, reproduction and behaviour. Taxonomic groups considered for inclusion are those classified as animal, plant, bacteria and/or fungi. Human data will not be included. Articles will be screened in two phases – firstly, Title and Abstract, before a full-text review. A single reviewer will screen all articles with an independent reviewer confirming articles for exclusion. Assessment of each article's quality will not be assessed for this evidence map. Results of the evidence map will be published in a narrative summary and visualised in a publicly available interactive map.