Urinary arsenic concentration and bronchial asthma prevalence in children from Arica, Chile

Introduction: Bronchial asthma is the most common chronic inflammatory disease in children. Globally, the asthma prevalence is estimated to be 10.8% in children aged 6 to 7 years and 13.8% in 13 to 14 years. Environmental factors have been associated with asthma, including exposure to metals. In Arica city, northern Chile, arsenic levels in soils of natural and anthropocentric origin have generated exposure in the population. Our study aim was to examine the association between urinary arsenic concentration and bronchial asthma diagnosis in children and adolescents from Arica. Methods: Cross-sectional design. A database of 2,026 subjects under 18 years of age enrolled in the Environmental Health Center between 2009 and 2021 was analyzed. Arsenic exposure was obtained through a urine sample and; diagnosis of bronchial asthma from the computerized system of management of explicit health guarantees. The association between urinary arsenic and bronchial asthma adjusted for confounding variables was assessed by logistic regression models. Results: The prevalence of bronchial asthma was 7.4%, and the median inorganic arsenic was 15 μg/L (IQ range: 7.0 - 26 μg/L). Children with urinary arsenic concentrations above the median were more likely to develop bronchial asthma [Odds Ratio (OR): 1.91 95% CI 1.26 - 2.91)] adjusted for sex, age, ethnicity, and urinary creatinine. Also, the adjusted model revealed a higher chance of developing asthma at concentrations ≥ 22 μg/L of arsenic (OR 1.90, 95% CI 1.12 - 3.20). Conclusion: This study reveals that urinary inorganic arsenic concentration might be associated with the development of bronchial asthma in children and adolescents. Despite the inherent limitations of cross-sectional data analysis, it is necessary to reduce arsenic exposure to prevent possible chronic health effects in children.