Association of Heavy Metals with Measures of Pulmonary Function in Youth: Findings from the 2011-2012 National Health and Nutrition Examination Survey (NHANES)

摘要

Exposure to cadmium, cobalt, lead, and manganese occurs through inhalation of industrial pollution and tobacco smoke, or ingestion of contaminated food and water. High exposure to these metals has been associated with decreased pulmonary function in adults. Little is known about these associations in children exposed at low levels in the United States (U.S.). We evaluated the cross-sectional associations of blood and urinary concentrations of cadmium, cobalt, lead, and manganese in relation to pulmonary function [forced expiratory volume in one second (FEV1; mL), forced vital capacity (FVC; mL), FEV1 to FVC ratio (FEV1:FVC), and midexhalation forced expiratory flow rate (FEF 25-75%; mL/second) in a sample of 1,234 U.S. children and adolescents aged 6 to 17 years from the 2011-2012 cycle of the National Health and Nutrition Examination Survey (NHANES). Survey-weighted linear regression models were performed to estimate beta coefficients and their 95% confidence intervals (CIs), adjusting for age, race, sex, height, family income, respiratory medication use, exposure to tobacco smoke, and urinary creatinine concentration (urinary exposure models only). Blood manganese concentration was inversely associated with FVC (3 for highest versus lowest quartile=-97.1, 95% CI=-230.6, 36.4; p for trend=0.03). The associations of blood manganese with both FEV1 and FVC differed by age (p for interactions.04 and 0.03, respectively), indicating an inverse trend that was strongest among youth aged 11-17. Urinary manganese was inversely associated with FEV1:FVC and FEF 25-75% (p=0.05 and 0.02, respectively). Urinary lead was inversely associated with FEF 25-75% (p=0.01). Our findings suggest that environmental manganese and lead exposure may adversely impact the pulmonary function of children. This association highlights the need to prioritize environmental health protection, evaluate these associations prospectively, and further investigate underlying mechanisms.