Association between Exposure to a Mixture of Metals, Parabens, and Phthalates and Fractional Exhaled Nitric Oxide : A Population-Based Study in Us Adults

Abstract

With the surge in personal skincare consumption, the effects of environmental endocrine-disrupting chemicals (EDCs) (eg, phthalates, parabens, and metals) on health have received much attention in recent years. However, few studies evaluated the relationship between the above chemicals and fractional exhaled nitric oxide (FeNO) (a biomarker of airway inflammation). We aimed to investigate comprehensively the relationship between three types of chemicals (six phthalate metabolites, two parabens, two heavy metals) and FeNO. Data of adults aged ≥20 years from the National Health and Nutrition Examination Survey (NHANES, 2007-2012) were collected and analyzed. The generalized linear (GLM) regression model was used to explore the association of chemicals with FeNO. The combined effect of 10 chemicals on the overall association with FeNO was evaluated by the weighted quantile sum regression (WQS) model. In addition, The Bayesian kernel machine regression (BKMR) model was explored to investigate the interaction and joint effects of multiple chemicals with FeNO. Of the 3296 study participants ultimately included, among the GLMs, we found that mercury (Hg) (β=0.842, 95%CI:0.324-1.359), mono-2-ethyl-5-carboxypentyl phthalate (MECPP) (β=0.526, 95%CI:0.014-1.039), methyl paraben (MPB) (β=0.468,95%CI:0.157-0.780), mono-(2-ethylhexyl phthalate (MEHP) (β=0.513, 95%CI:0.070-0.955) were positively correlated with FeNO. In the WQS model, the combined effect of chemicals almost had a significantly positive association with FeNO and the top three contributors to the WQS index were Hg (40.2%), MECPP (22.1%), and MPB (19.3%). BKMR model analysis showed that there may be interactions between MPB and Hg, MCOP and Hg and the overall effect of the mixture showed a positive correlation with FeNO. In conclusion, our study strengthens the credibility of the view that EDCs can affect respiratory health. In the future, we should be particularly careful with products containing Hg, MECPP, MPB, and MEHP for the prevention of respiratory diseases.

Keywords: Fractional exhaled nitric oxide, BKMR, WQS, Parabens, Metals, Phthalates