Inorganic arsenic exposure and modifying factors: a systematic evidence map

Evidence maps employing systematic review screening tools have been used for identifying and categorizing chemical-specific literature that may be potentially relevant to scientific assessment. Inorganic arsenic (iAs), naturally distributed throughout the Earth's crust, is found in water, food, soil, and air. The epidemiologic evidence shows that iAs is associated with cancer and noncancer human health outcomes. Increased susceptibility to iAs-related disease is associated both with intrinsic and extrinsic factors. Our objective was to explore the use and feasibility of the systematic evidence map (SEM) approach to provide a clearer picture of the available literature on modifying factors that may alter the relationship between iAs exposure and health effects. A literature search (2014-2022) was conducted using PubMed, Web of Science, and Toxnet to identify studies with modifying factors of iAs health effects defined in Populations, Exposures, Comparators, Outcomes (PECO) criteria. Where applicable, health effects were also categorized. The literature search identified 584 studies with modifying factors that met the PECO criteria. Studies on the following modifying factors were identified: alcohol consumption (n= 8), chemical co-exposure (n= 104), genetic polymorphisms (n= 172), lifestages (n=228), microbiome (n=6), nutritional deficiencies (n=150), pre-existing conditions (n= 9), sex (n=65), smoking (n= 45), and other (e.g., arsenic metabolism, epigenetics, UV/sun exposure, DNA damage/repair, coffee consumption) (n=227). The SEM method was effectively utilized to identify studies on modifying factors for inorganic arsenic.