Exploring the link between exposure to volatile organic chemicals and incidence of infertility:A cross-sectional study

Abstract

Background: Growing evidence suggests that environmental pollutants exert a detrimental impact on female fertility. Among these pollutants, volatile organic compounds (VOCs), easily encountered in the environment, have garnered significant attention as prevalent airborne contaminants. Nevertheless, a definitive consensus regarding the association between VOCs and the incidence of infertility remains elusive.

Method: Conducted as a cross-sectional study, this research utilized data from three survey cycles of the NHANES program spanning from 2013 to 2018. The objective was to delve into the relationship between volatile organic compounds and the prevalence of infertility. The definition of infertility relied upon information derived from the reproductive health questionnaire. In order to comprehensively explore this relationship, various analytical models, including logistic regression, weighted quantile sum (WQS), and Bayesian kernel-machine regression (BKMR), were employed.

Result: A total of 1098 participants, 120 in the infertility group and 978 in the control group, were included. All 15 volatile organic compounds showed higher concentrations in the infertility group's urine. Multivariate regression revealed that the highest AMCC (N-acetyl-S-(N-methylcarbamoyl)-L-cysteine) and CYMA (2-hydroxyethyl mercapturic acid) quartiles associated with significant infertility increases, approximately 191 % and 128 %, respectively, versus the lowest quartile (OR for AMCC = 2.91; 95%CI: 1.33, 6.37; OR for CYMA = 2.28; 95%CI: 1.01, 5.15). This emphasizes AMCC and CYMA's role in infertility, supported by WQS and BKMR studies. Inflammation mediates AMCC's impact on infertility, enhancing our understanding of volatile organic compounds and reproductive health.

Conclusion: The study highlights the correlation between VOCs exposure, notably AMCC and CYMA, and infertility. It identifies inflammation as a mediating factor connecting AMCC to infertility.

Keywords: Environment pollution; Inflammation; NHANES; Volatile organic chemicals.

Graphical abstract

Fig. 1

Flowchart of participants included in this study. NHANES, National Health and Nutrition Examination Survey. VOCs, volatile organic compound metabolites.

Fig. 2

The association between urine VOCs and infertility. The solid red line represents the smooth curve fit between variables. Blue bands represent the 95 % confidence interval from the fit.

Fig. 3

(A) The thermogram of urinary VOCs mixture displays positive correlations in blue. (B-C) Weight map for WQS regression index of urine VOCs mixture. (D) The comprehensive impact of urine VOCs mixture on infertility in the BKMR model.