Urinary 3-phenoxybenzoic acid (3-PBA) concentration and pulmonary function in children: A National Health and Nutrition Examination Survey (NHANES) 2007–2012 analysis

Epidemiological studies have reported association of urinary 3-phenoxybenzoic acid (3-PBA), a major metabolite of pyrethroid insecticides (PYRs), with respiratory disease. However, knowledge regarding its effect on pulmonary function in susceptible children is limited. This study aimed to assess the associations between environmental 3-PBA concentrations and pulmonary function in children aged 6–17 years. Using data on 1174 children aged 6–17 years from the U.S. National Health and Nutrition Examination Survey (NHANES) 2007–2012, the exposure to PYRs was assessed by measuring urinary 3-PBA concentrations and pulmonary function was assessed by spirometry. Multivariable linear regression and generalized linear models (GLMs) were used to examine the associations between 3-PBA concentrations and pulmonary function in children, controlling for confounders. We found that 3-PBA concentrations were inversely associated with forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and peak expiratory flow (PEF) in the pediatric population (p-trends < 0.05). When stratified by age (6–10 and 11–17 years) and gender (boys and girls), the adverse effects of PYR exposures on pulmonary function were more pronounced among boys aged 11–17 years. Among this age group, 3-PBA concentrations were negatively associated with FEV1, FVC, forced expiratory flow between 25% and 75% of FVC (FEF25–75%), and PEF. However, among children aged 6–10 years, no associations were found between 3-PBA concentrations and any of the pulmonary function measures, in either boys or girls. Our findings suggest that environmental PYR exposures may adversely affect children's pulmonary function, with the strongest associations among 11–17 years old boys.