Exposure to volatile organic compounds induces cardiovascular toxicity that may involve DNA methylation

Assessing the impact of volatile organic compounds on cardiovascular health: Insights from the National Health and Nutrition Examination Survey 2011-2020

Volatile organic compounds (VOCs) are environmental pollutants that may negatively impact cardiovascular health. This study investigates the association between VOC mixtures, measured through urinary VOC metabolites (VOCMs), and cardiovascular health using Life's Essential 8 (LE8) scores. Data from the National Health and Nutrition Examination Survey (NHANES) 2011-2020 were analyzed for 2967 adults aged 20-79 years. Multiple statistical methods, including correlation analysis, variance inflation factor (VIF) analysis, quantile g-computation (q-gcomp), and Bayesian kernel machine regression (BKMR), were applied to assess the association between VOCMs and LE8 scores. Sensitivity analyses were conducted with different random seeds and subsampling techniques to confirm robustness. Correlation and VIF analyses revealed strong collinearity among VOCMs, highlighting the need for advanced models. Survey-weighted regression indicated that lower VOC exposure was associated with better cardiovascular health. Q-gcomp identified both positive and negative associations between individual VOCMs and LE8 scores, with some unexpected positive associations. BKMR highlighted the complex mixture effects of VOCMs on cardiovascular health. Sensitivity analyses confirmed the consistency of these findings. This study underscores the intricate relationship between VOC exposure and cardiovascular health and the necessity of advanced statistical methods for mixture analysis. Despite some unexpected findings, the results suggest that VOC exposure, as reflected by urinary VOCMs, is associated with adverse cardiovascular health outcomes. Further research is needed to clarify the biological mechanisms and implications of these associations.

Maternal multivitamin supplementation mitigates the risk of fetal congenital heart disease associated with high indoor total volatile organic compounds exposure in east china: a case-control study

BACKGROUND

Congenital heart disease (CHD) is a common birth defect. Our previous studies suggest that indoor air pollution, especially total volatile organic compounds (TVOCs), may increase fetal CHD risk, whereas vitamin and folic acid (FA) supplements in early pregnancy might offer protection against CHD. However, limited research has explored whether FA or multivitamin supplementation can mitigate the effects of TVOCs exposure on CHD.

METHODS

We conducted a case-control study to investigate the association between maternal nutrient supplementation, household indoor air pollutant exposure during pregnancy, and CHD in offspring. Pregnant women with 22-30 gestational weeks were recruited from two hospitals in East China between January 2016 and March 2022. A comprehensive approach was used, incorporating questionnaires to collect nutrient supplement information, blood sample analysis to detect serum folate, vitamin B12, and homocysteine (HCY) concentrations, and field investigations to assess indoor benzene, toluene, xylene, formaldehyde, and TVOCs exposures. Logistic regression analysis was performed to identify CHD risk factors, and stratified analysis was used to evaluate the combined effects of nutrient supplementation and TVOCs on CHD.

RESULTS

The study included 53 cases and 77 controls. Logistic regression analysis identified high maternal serum HCY (> 6.125 µmol/L) and high household TVOCs exposure (> 0.0165 mg/m³) as risk factors for CHD in offspring, with adjusted odds ratios of 2.98 (95% CI: 1.31-6.36) and 9.23 (95% CI: 3.78-22.53), respectively. Regular multivitamin supplementation mitigated the risk of high TVOCs exposure on fetal CHD, while the adverse effect of high serum HCY-related CHD risk was attenuated in the group with regular FA supplementation.

CONCLUSION

Exposure to high indoor TVOCs concentrations increases the risk of fetal CHD. Regular multivitamin supplementation may reduce the adverse effects of high TVOCs exposure on fetal CHD.

Ambient volatile organic compounds in a typical industrial city in southern China: Impacts of aromatic hydrocarbons from new industry

New industrial parks, including fine chemical, medical manufacturers, etc., are emerging in modern cities in China, whereas their emissions and impacts have not been fully illuminated. In this study, ambient volatile organic compounds (VOCs) in Huizhou were measured in three functional zones, namely new industrial, roadside, and residential zones. The average mixing ratios of total VOCs were as follow: industrial (56.22 ± 15.06 ppbv) > roadside (39.30 ± 12.96 ppbv) > residential (26.03 ± 7.31 ppbv). The ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAP) of VOCs in the industrial zone were 1.5-2.3 and 1.7-3.1 times those in the other zones, respectively. Aromatics contributed the most to OFP (39.8 % - 44.8 %) and SOAP (78.9 % - 91.0 %), with much less contributions to VOCs mixing ratios (18.3 % - 21.2 %). Naphthalene was the most abundant aromatic species across the three zones and ranked among the top contributors to OFP and SOAP among all VOCs species. Source apportionment identified that new industrial emissions and solvent use was the largest VOCs contributor in the industrial zone (53.9 %), traffic-related emissions dominated in the roadside zone (40.7 %), while new industrial and traffic-related emissions contributed similar in the residential zone (32.9 % and 34.7 %, respectively). The carcinogenic and non-carcinogenic risks of hazardous VOCs were above the acceptable threshold, primarily due to new industrial and traffic-related emissions. Our results suggested to strengthen the control of new industrial emissions and aromatics sources in Huizhou city to improve air quality and protect human health.

Exposure to volatile organic compounds and mortality in US adults: A population-based prospective cohort study

Volatile organic compounds (VOCs) are ubiquitous in both indoor and outdoor environments. Evidence on the associations of individual and joint VOC exposure with all-cause and cause-specific mortality is limited. Measurements of 15 urinary VOC metabolites were available to estimate exposure to 12 VOCs in the National Health and Nutritional Examination Survey (NHANES) 2005-2006 and 2011-2018. The environment risk score (ERS) was calculated using LASSO regression to reflect joint exposure to VOCs. Follow-up data on death were obtained from the NHANES Public-Use Linked Mortality File through December 31, 2019. Cox proportional hazard models and restricted cubic spline models were applied to evaluate the associations of individual and joint VOC exposures with all-cause and cause-specific mortality. Population attributable fractions were calculated to assess the death burden attributable to VOC exposure. During a median follow-up of 6.17 years, 734 (8.34 %) deaths occurred among 8799 adults. Urinary metabolites of acrolein, acrylonitrile, 1,3-butadiene, and ethylbenzene/styrene were significantly associated with all-cause, cardiovascular disease (CVD), respiratory disease (RD), and cancer mortality in a linear dose-response manner. Linear and robust dose-response relationships were also observed between ERS and all-cause and cause-specific mortality. Each 1-unit increase in ERS was associated with a 33.6 %, 39.1 %, 109.8 %, and 67.8 % increase for all-cause, CVD, RD, and cancer mortality risk, respectively. Moreover, joint exposure to VOCs contributed to 17.95 % of all-cause deaths, 13.49 % of CVD deaths, 35.65 % of RD deaths, and 33.85 % of cancer deaths. Individual and joint exposure to VOCs may enhance the risk of all-cause and cause-specific mortality. Reducing exposure to VOCs may alleviate the all-cause and cause-specific death burden.