PFAS health effects database: Protocol for a systematic evidence map

Background: Per- and polyfluoroalkyl substances (PFAS) confer waterproof, greaseproof, and non-stick properties when added to consumer products. They are also used for industrial purposes including in aqueous film forming foams for firefighting. PFAS are ubiquitous in the environment, are widely detected in human biomonitoring studies, and are of growing regulatory concern across federal, state, and local governments. Regulators, scientists, and citizens need to stay informed on the growing health and toxicology literature related to PFAS. Objectives: The goal of this systematic evidence map is to identify and organize the available health and toxicology related literature on a set of 29 PFAS of emerging and growing concern. Search and study eligibility: We will search the electronic database PubMed for health or toxicological studies on 29 PFAS of emerging concern. Eligible studies must contain primary research investigating the link between one or more of the PFAS of interest and a health effect, toxicological, or biological mechanistic endpoint. Study appraisal and synthesis methods: Title and abstract screening and full text review will require a single reviewer for inclusion to the next level and two independent reviewers for exclusion. Study quality will not be conducted for this evidence mapping. Study characteristics will be extracted and coded from the included studies and checked for accuracy by a second reviewer. The extracted and coded information will be visualized in a publicly available, interactive database hosted on Tableau Public. Results of the evidence mapping will be published in a narrative summary.