Dose-Response of the Pro-Inflammatory Potential Induced by Indoor Settled Dust from Homes with Different Levels of Water-Damage during Hurricane Maria in San Juan, Puerto Rico

Rationale: Hurricane Maria (September 2017), caused extensive indoor wind- and water-damage to homes throughout Puerto Rico. This environmental hazard increases the risk for household occupants to chronic exposures to indoor pollution, which can result in chronic immune reactivity. We hypothesized that settled dust from water-damaged homes will induce a higher dose-dependent pro-inflammatory potential than non-water damaged homes. Method(s): Settled dust samples were collected from homes (n=50) within an affected community in San Juan, PR, one year after Hurricane Maria made landfall. Based on self-reported surveys, of 26 homes in areas from no external flooding, 13 had internal water damage; 24 homes were from in areas with external flooding (11 with some internal water damage and 13 had inside flooding). Settled dust water extracts were prepared, and diluted (3:10, 1:10, 3:100, 1:100) and non-diluted extracts were assessed for their pro-inflammatory potential based on the induced concentration of the pro-inflammatory cytokine interleukin(IL)-1beta in the human whole-blood pyrogen assay. Result(s): Undiluted extracts induced 24% to 46% higher IL-1beta (p < 0.001) than diluted extracts, and extracts diluted 3:10 induced 17% higher (p = 0.04 to 0.009) than 3:100 and 1:100. Extracts with the highest diluted retained IL-1beta-inducing potential higher than baseline. Also, extracts from homes that self-reported inside flooding induced a higher dose-response (p < 0.05) than all other homes. Conclusion(s): Homes that self-reported been flooding during Hurricane Maria potentially increased the likelihood of exposure to indoor contaminants with the potential to induce pro-inflammatory immune activation in a dose-dependent manner.Copyright © 2020