Elemental Sulfur Use and Associations with Pediatric Lung Function and Respiratory Symptoms in an Agricultural Community (California, USA)

BACKGROUND: Elemental sulfur, “the oldest of all pesticides,” is the most heavily used agricultural pesticide in California and Europe. Sulfur is considered relatively safe and is used in both conventional and organic farming systems. Adverse respiratory effects have been reported in applicators and animals, but the effect on residential populations, and especially on children living in proximity to fields treated with elemental sulfur, is not known. OBJECTIVES: We evaluated associations between residential proximity to elemental sulfur applications and respiratory symptoms and spirometry of children living in an agricultural community. METHODS: Participants were enrolled in the CHAMACOS longitudinal birth cohort. We collected respiratory symptomatology for 347 children at 7 y of age and measured spirometry on a subset of 279. Of these, estimations of proximity to sulfur application and relevant covariate data were available for 237 and 205 children for whom we had symptomatology information and [Formula: see text] measurements, respectively. Data from the California Pesticide Use Reporting System were used to estimate the amount of elemental sulfur applied within 0.5, 1, and [Formula: see text] of a child’s residence during the week, month, and 12 mo prior to pulmonary evaluation. Regression models controlled for maternal smoking during pregnancy; season of birth; [Formula: see text] (particulate matter [Formula: see text] in aerodynamic diameter); breast feeding duration; child’s sex, age, and height; technician; and other covariates. RESULTS: Adverse associations with respiratory outcomes were found for sulfur applications within 0.5- and [Formula: see text] radii. Specifically, asthma medication usage and respiratory symptoms increased [[Formula: see text]; 95% confidence interval (CI): 1.50, 8.23, [Formula: see text]; [Formula: see text]; 95% CI: 1.27, 3.46, [Formula: see text] , respectively] and [Formula: see text] decreased ([Formula: see text]; 95% CI: [Formula: see text] , [Formula: see text] , [Formula: see text]) per 10-fold increase in the estimated amount of sulfur used within [Formula: see text] of child residence during the year prior to pulmonary evaluation. CONCLUSIONS: This study suggests that elemental sulfur use, allowed in both organic and conventional farming, in close proximity to residential areas, may adversely affect children’s respiratory health. https://doi.org/10.1289/EHP528