Survey of human studies that met PECO criteria, organized by route of exposure, population, and health systems evaluated. Numbers represent the number of references that investigated a health system, not the number of references that identified an association with exposure to naphthalene. If a reference evaluated multiple health systems, it is shown here multiple times. Column totals, row totals, and grand total indicate total numbers of distinct references. See the “Human Evidence” tab in the interactive dashboard in Tableau Public for a more detailed description of study design and results (https://public.tableau.com/views/NaphthaleneEvidenceMap/ReadMe?:language=en&:display_count=y&publish=yes&:origin=viz_share_link). Note: PECO, populations, exposures, comparators, and outcomes.