Environment/Climate Change
The association between hydrogen sulfide exposure and blood pressure in Carson, CA Arbor Quist* Arbor Quist Alexander Silverman Jerry Yuxuan Wu Meredith Franklin Jill Johnston
Hydrogen sulfide (H2S) is a toxic, colorless, odorous, gas known for its “rotten egg” smell. H2S exposure at moderate levels can harm the respiratory, neurological, and cardiovascular systems, and high-level exposure can result in death. Literature on the health effects of low-level H2S exposure is mixed, including literature on the association between low-level H2S exposure and blood pressure (BP). No studies to our knowledge have examined this association using modeled H2S. For this study, we partnered with community organizations in Carson, California, where residents have been concerned about odors and where elevated levels of H2S have been measured. Carson was also the location of a H2S crisis (concentrations reached 7000 ppb) in October 2021. We recruited 265 participants from the Carson area and collected 3 BP measurements for each participant ~1 year post-disaster. We averaged the BP measurements and defined hypertension as >130 mmHg systolic or >80 mmHg diastolic. We modeled H2S across time and space using Extreme Gradient Boosting, incorporating H2S concentrations from 13 ambient stationary monitors, wind speed, wind direction, and distance to refinery, among other variables. Participants were assigned the maximum H2S concentration at their home during the 30 days prior to their study visit. We conducted multivariable linear regression to examine the association between modeled H2S exposure (split into tertiles) and hypertension, adjusting for BMI, smoking status, distance to freeway, sex, age, and use of antihypertension medications. We observed higher odds of hypertension among participants exposed to the highest tertile of H2S (0.6-2.1 ppb) compared to the lowest tertile (0.1-0.5 ppb; OR=1.23, 95% CI: 1.09, 1.39). The association was stronger when restricted to participants who were exposed to >5 ppb H2S during the 2021 H2S crisis (OR=1.38, 95% CI: 1.17, 1.63, N=143). H2S exposure, even at relatively low levels, can increase odds of hypertension.