Urinary volatile organic compound metabolites and reduced lung function in U.S. adults

Independent and joint effects of volatile organic compounds on pulmonary function in U.S. adults from NHANES: the mediating role of platelet-to-lymphocyte ratio

Volatile organic compounds (VOCs) are known to impair pulmonary function. However, the specific VOC with the main significant impact on pulmonary function and the joint effect of combined VOC exposure on pulmonary health, and the underlying mechanisms remain unclear. We used the of data 1,697 participants aged ≥18 years old from the National Health and Nutrition Examination Survey 2007-2012. Forced expiratory volume in the first 1.0 s (FEV1), pre-bronchodilator forced vital capacity (FVC), peak expiratory flow rate (PEF) and FEV1/FVC % were used to evaluate pulmonary function. A covariate-adjusted multiple linear regression model evaluated associations between pulmonary function and blood concentrations of seven selected VOCs. Additionally, Bayesian kernel machine regression (BKMR) and weighted quantile sum (WQS) regression were employed to assess combined VOC effects, interactions, and nonlinear dose-response relationships. Parallel mediation analyses explored the mediating role of platelet-to-lymphocyte ratio (PLR) in the associations between VOC mixtures and pulmonary function, utilizing a WQS-derived VOC index. In an analytical sample of 1,697 general adults, the concentrations of blood 1,4-dichlorobenzene, m-/p-xylene, bromodichloromethane, and nitromethane were significantly negatively correlated with pulmonary function, whilst dibromochloromethane was significantly positively correlated with pulmonary function. The joint effect of the seven blood VOCs was also negatively associated with pulmonary function. Particularly, 1,4-dichlorobenzene (PIP = 0.992 for FEV1; 0.998 for FVC) and nitromethane (PIP = 0.990 for FEV1; 1.000 for FVC; 0.845 for PEF) as the most influential VOCs contributing to the overall mixture effect. PLR partially mediated the association between VOC mixtures and pulmonary function, particularly impacting FEV1, FVC, and PEF. This study demonstrated that in addition to chloroform, dibromochloromethane and toluene, the other four blood VOCs were associated with pulmonary function impairment. Their combined exposure effects reflect realistic environmental scenarios. Further research is needed to elucidate the underlying biological mechanisms of these associations.

Association between exposure to volatile organic compounds and atherogenic index of plasma in NHANES 2011-2018

Volatile organic compounds (VOCs) are prevalent in daily life, yet the relationship between VOCs exposure and the atherogenic index of plasma (AIP) remains inadequately explored, especially in populations with high levels of exposure. This study aims to investigate the non-linear association between VOCs exposure and AIP in the U.S. adult population. Data from the National Health and Nutrition Examination Survey (NHANES) collected between 2011 and 2018 were analyzed. A range of statistical techniques, including Spearman's correlation analysis, weighted quantile sum (WQS), multivariate logistic regression, restricted cubic splines (RCS), stratified threshold models, and bayesian kernel machine regression (BKMR), were systematically employed to assess the relationship between high-dose VOCs exposure and AIP in U.S. adults. The study included 6,027 participants, with an average age of 37 (18-59), and 50.46% were male. Of these, 3,011 had elevated AIP levels. The Mann-Whitney U test compared VOCs exposure across quartiles (Q1-Q4). Spearman models revealed strong joint exposure effects between VOCs like IPMA3 and HMPMA (ρ = 0.97). WQS regression showed a positive association between VOCs and total cholesterol (TC) (β = 5.45, 95% CI = 5.42-5.58, P = 0.04) and high-density lipoprotein cholesterol (HDL-C) (β = 1.07, 95% CI = 1.03-1.10, P = 0.02). After adjusting for confounders, logistic regression revealed that VOCs such as 3-4MHA, 34DMA, AAMA, ATCA, CYMA, HEMA, and SBMA were linked to higher AIP. RCS analysis indicated a nonlinear association between VOCs and AIP. Stratified modeling found that ATCA was significantly and positively associated with AIP (OR = 1.60, 95% CI = 1.20-2.14, p < 0.01), and that when ATCA levels exceeded 128.60 ng/mL, there was a 60% increased risk of elevated AIP. Higher urinary VOCs levels, particularly ATCA, are significantly associated with increased AIP, offering new insights into the potential link between VOCs exposure and cardiovascular disease.

Exposure to volatile organic compounds and chronic respiratory disease mortality, a case-cohort study

BACKGROUND

Chronic respiratory diseases (CRDs) are the third leading cause of death worldwide. Data of the associations between specific volatile organic compounds (VOCs), a major component of air pollution and tobacco smoke, and subsequent CRD mortality in the general population are scarce.

METHODS

In a case-cohort analysis within the population-based Golestan cohort study (n = 50045, aged 40-75 years, 58% women, enrollment: 2004-2008, northeastern Iran), we included all participants who died from CRD during follow-up through 2018 (n = 242) as cases and stratified them into 16 strata defined by age, sex, residence, and tobacco smoking. Subcohort participants (n = 610) were randomly selected from all eligible cohort participants in each stratum, and sampling fractions were calculated. Baseline urine samples were used to measure 20 VOCs using ultra high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry. After excluding participants with previous history of CRDs, we used stratified Cox regression models weighted by the inverse sampling fractions (i.e. inverse probability weighting) adjusted for potential confounders, including urinary cotinine and pack-years of smoking, to calculate hazard ratios (HR) for the associations between biomarker tertiles and CRD mortality.

RESULTS

Data from 545 non-case, sub-cohort participants and 149 cases (69.1% chronic obstructive pulmonary disease, 13.4% asthma, 17.5% other CRDs) were assessed in this study. During a follow-up of 10.5 years, associations [2nd and 3rd vs. 1st tertiles, HR (95% confidence interval), p for trend] were observed between metabolites of acrolein [1.56 (0.64,3.79), 3.53 (1.53,8.16), 0.002] and styrene/ethylbenzene [1.17 (0.53,2.60), 3.24 (1.37,7.66), 0.005] and CRD mortality, which persisted after excluding the first four years of follow-up.

CONCLUSION

Our findings support prior research suggesting respiratory toxicity of VOCs. Further investigation and monitoring of these compounds, especially acrolein and styrene/ethylbenzene, as CRD risk factors, are recommended.

Volatile organic compounds exposure associated with skin cancer among U. S. adults: results from NHANES 2011-2018

Skin cancer, including melanoma, squamous cell carcinoma, and basal cell carcinoma, ranks as the fifth most common cancer globally. It exhibits a high incidence rate, with men being more susceptible, particularly as they age, making middle-aged and older men a high-risk group. This study analyzed data from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018 to investigate the relationship between skin cancer and 15 urinary volatile organic compounds (VOC). VOC are a class of gases that are volatile at room temperature and atmospheric pressure, with carbon as the main structural atom. We used binary logistic regression to comprehensively assess the potential association between each urinary VOC exposure and skin cancer, while weighted quantile sum regression was employed to explore the associations of mixed co-exposures. Specific VOC, notably mercapturic acid (MA), showed significant correlations with skin cancer risk, particularly in females. Our research presents a comprehensive assessment of the link between VOC and skin cancer, aiming to provide a scientific basis for understanding the correlation between VOC and skin cancer within human populations.

1-Bromopropane induces mitochondrial damage and lipid metabolism imbalance in respiratory epithelial cells through the PGC-1α/PPARα pathway

1-Bromopropane (1-BP) has become a new air pollutant in occupational and living environments due to its advantages in industrial applications and as a representative compound of volatile organic compounds (VOCs). As an irritant, its damaging effects on respiratory epithelium are worthy of further study. This study aimed to explore the damage effects of 1-BP on respiratory epithelial cells and reveal its underlying mechanisms. We found that exposure to 1-BP markedly reduced the viability of respiratory epithelial cells in a dose-dependent manner, and induced oxidative stress and vacuolation changes in respiratory epithelial cells. Subsequently, through RNA-seq analysis, we identified that the 1-BP-induced damage of respiratory epithelial cells was related to the mitochondrial function pathway and further verified that 1-BP caused mitochondrial damage of respiratory epithelial cells, which was manifested as ultrastructural damage, decreased membrane potential, ATP, and MFN2 levels. These damages were associated with cellular oxidative stress responses. Pretreating cells with the agonists of PGC-1α and PPARα, we revealed that 1-BP affected the expression of PGC-1α and interfered with its coactivator PPARα levels, causing an increase in the expression of lipid-producing genes and a decrease in the expression of lipid-decomposing genes, thus leading to a lipid accumulation in respiratory epithelial cells. Meanwhile, the imbalance of lipid metabolism in respiratory epithelial cells induced by 1-BP further caused mitochondrial damage, and the effect was bidirectional. These findings suggested that 1-BP has a potential role in inducing respiratory epithelial cell damage and is associated with the PGC-1α/PPARα signaling pathway.

Association of 1-bromopropane exposure with asthma prevalence: A Korean National health and Nutritional examination survey (2020-2021)-based study

Exposure to 1-bromopropane (1-BP) is an emerging environmental and health concern due to its increasing environmental prevalence. Although the health effects of 1-BP exposure have been under-recognized, current evidence suggests the possibility of adverse pulmonary health effects due to 1-BP exposure. However, the association between 1-BP exposure and asthma prevalence remains unclear. Thus, we aimed to examine the association between 1-BP exposure and asthma prevalence in the general population. Using nationally representative data, we explored the potential impacts of indoor air quality (IAQ)-related behavioral factors on the level of 1-BP exposure. This study included 1506 adults from the 2020-2021 Korea National Health and Nutrition Examination Survey. The prevalence of asthma was based on self-reported physician-diagnosed asthma. Urinary N-acetyl-S-(n-propyl)-L-cysteine (BPMA) levels were measured as a biomarker of 1-BP exposure, using high-performance liquid chromatography-mass spectrometry. Multiple logistic regression models were performed to investigate the associations between urinary BPMA metabolite and asthma prevalence after adjusting for potential confounders. Log-linear multiple regression models were used to examine the association between IAQ-related behavior and urinary BPMA concentration. Forty-seven individuals with asthma and 1459 without asthma were included. Individuals in the highest quartile of urinary BPMA concentration had a 2.9 times higher risk of asthma than those in the lowest quartile (odds ratio [OR]: 2.85, 95% confidence interval [CI]: 1.02-7.98). The combination of natural and mechanical ventilation was associated with a reduced urinary BPMA concentration. Our findings suggest that 1-BP exposure is associated with the prevalence of asthma in adults and revealed higher urinary levels of BPMA in our study population compared to those in other countries. Given the emerging importance of IAQ, actively managing and modifying behavioral patterns to reduce 1-BP exposure in indoor environments could substantially attenuate the risk of asthma-related to 1-BP exposure.

Disinfection byproducts in US drinking water and cancer mortality

Trihalomethanes, the main drinking water disinfection byproducts, may be carcinogenic and are regulated to amaximum total trihalomethanes (TTHM) of 80 µg/l in the US. We aimed to determine whether total and individual trihalomethanes in drinking water across the US are associated with higher cancer mortality in 6,260 adult participants to the National Health and Nutrition Examination Surveys from 1999 to 2008 followed for mortality until 2019 (median: 14.4 years). At baseline, the geometric mean (standard error) of TTHM in drinking water was 9.61 (0.85) µg/l. During follow-up, 873 deaths occurred, including 207 from cancer. In Cox proportional hazards regression adjusted for relevant covariates, drinking water TTHM (HR: 1.45, 95% CI: 1.16-1.82), chloroform (HR: 1.35, 95% CI: 1.12-1.64), and bromodichloromethane (HR: 1.30, 95% CI: 1.05-1.59) were associated with 30% to 45% higher cancer mortality. Therefore, drinking water trihalomethanes, especially chloroform and bromodichloromethane maybe risk factors for cancer mortality.

Combined association of urinary volatile organic compounds with chronic bronchitis and emphysema among adults in NHANES 2011-2014: The mediating role of inflammation

Evidence on the association of volatile organic compounds (VOCs) with chronic bronchitis (CB) and emphysema is spare and defective. To evaluate the relationship between urinary metabolites of VOCs (mVOCs) with CB and emphysema, and to identify the potential mVOC of paramount importance, data from NHANES 2011-2014 waves were utilized. Logistic regression was conducted to estimate the independent association of mVOCs with respiratory outcomes. Least absolute shrinkage and selection operator (LASSO) regression was performed to screen a parsimonious set of CB- and emphysema-relevant mVOCs that were used for further co-exposure analyses of weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR). Mediation analysis was employed to detect the mediating role of inflammatory makers in such associations. In single exposure analytic model, nine mVOCs were individually and positively associated with CB, while four mVOCs were with emphysema. In WQS regression, positive association between LASSO selected mVOCs and CB was identified (OR = 1.82, 95% CI: 1.25 to 2.69), and N-acetyl-S-(4-hydroxy-2-butenyl)-l-cysteine (MHBMA3) weighted the highest. Results from BKMR further validated such combined association and the significance of MHBMA3. As for emphysema, significantly positive overall trend of mVOCs was only observed in BKMR model and N-acetyl-S-(N-methylcarbamoyl)-l-cysteine (AMCC) contributed most to the mixed effect. White blood cell count (WBC) and lymphocyte number (LYM) were mediators in the positive pattern of mVOCs mixture with CB, while association between mVOCs mixture and emphysema was significantly mediated by LYM and segmented neutrophils num (NEO). This study demonstrated that exposure to VOCs was associated with CB and emphysema independently and combinedly, which might be partly speculated that VOCs were linked to activated inflammations. Our findings shed novel light on VOCs related respiratory illness, and provide a new basis for the contribution of certain VOCs to the risk of CB and emphysema, which has potential public health implications.

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.

Urinary volatile organic compound metabolites and COPD among US adults: mixture, interaction and mediation analysis

BACKGROUND

Volatile organic compounds (VOCs) encompass hundreds of high production volume chemicals and have been reported to be associated with adverse respiratory outcomes such as chronic obstructive pulmonary disease (COPD). However, research on the combined toxic effects of exposure to various VOCs on COPD is lacking. We aimed to assess the effect of VOC metabolite mixture on COPD risk in a large population sample.

METHODS

We assessed the effect of VOC metabolite mixture on COPD risk in 5997 adults from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2020 (pre-pandemic) using multivariate logistic regression, Bayesian weighted quantile sum regression (BWQS), quantile-based g-Computation method (Qgcomp), and Bayesian kernel machine regression (BKMR). We explored whether these associations were mediated by white blood cell (WBC) count and total bilirubin.

RESULTS

In the logistic regression model, we observed a significantly increased risk of COPD associated with 9 VOC metabolites. Conversely, N-acetyl-S-(benzyl)-L-cysteine (BMA) and N-acetyl-S-(n-propyl)-L-cysteine (BPMA) showed insignificant negative correlations with COPD risk. The overall mixture exposure demonstrated a significant positive relationship with COPD in both the BWQS model (adjusted odds ratio (OR) = 1.30, 95% confidence interval (CI): 1.06, 1.58) and BKMR model, and with marginal significance in the Qgcomp model (adjusted OR = 1.22, 95% CI: 0.98, 1.52). All three models indicated a significant effect of the VOC metabolite mixture on COPD in non-current smokers. WBC count mediated 7.1% of the VOC mixture associated-COPD in non-current smokers.

CONCLUSIONS

Our findings provide novel evidence suggesting that VOCs may have adverse associations with COPD in the general population, with N, N- Dimethylformamide and 1,3-Butadiene contributing most. These findings underscore the significance of understanding the potential health risks associated with VOC mixture and emphasize the need for targeted interventions to mitigate the adverse effects on COPD risk.

Urinary Volatile Organic Compound Metabolites Are Associated with Reduced Lung Function in U.S. Children and Adolescents

(1) Background: Volatile organic compounds (VOCs) are indoor pollutants absorbed by inhalation. The association of several VOCs with lung function in children and adolescents is unknown. (2) Methods: We analyzed 505 participants, 6-17-year-olds from the 2011-2012 National Health and Nutrition Examination Survey. Multiple linear regression models were fitted to estimate the associations of VOC metabolites with spirometry outcomes adjusting for covariates. (3) Results: Urinary metabolites of xylene, acrylamide, acrolein, 1,3-butadiene, cyanide, toluene, 1-bromopropane, acrylonitrile, propylene oxide, styrene, ethylbenzene, and crotonaldehyde were all detected in ≥64.5% of participants. Forced expiratory volume in 1 s (FEV1) % predicted was lower in participants with higher levels of metabolites of acrylamide (β: -7.95, 95% CI: -13.69, -2.21) and styrene (β: -6.33, 95% CI: -11.60, -1.07), whereas the FEV1 to forced vital capacity (FVC) ratio % was lower in children with higher propylene oxide metabolite levels (β: -2.05, 95% CI: -3.49, -0.61). FEV1 % predicted was lower with higher crotonaldehyde metabolite levels only in overweight/obese participants (β: -15.42, 95% CI: -26.76, -4.08) (Pinteraction < 0.001) and with higher 1-bromopropane metabolite levels only in those with serum cotinine > 1 ng/mL (β: -6.26, 95% CI: -9.69, -2.82) (Pinteraction < 0.001). (4) Conclusions: We found novel associations of metabolites for acrylamide, propylene oxide, styrene, 1-bromopropane and crotonaldehyde with lower lung function in children and adolescents.

The urinary metabolites of volatile organic compounds and asthma in young children: NHANES 2011-2018

The vast majority of volatile organic compounds (VOCs) are of biological origin and do not affect human health, while some VOCs or their oxidation products can damage the respiratory system, nervous system, digestive system and blood system after long-term inhalation by humans. There is limited evidence regarding the association of VOCs exposure with childhood asthma. In this study, we examined the associations between metabolites of VOCs (mVOCs) in urine and childhood asthma. We included a total of 1542 children aged 3-12 years who had information on urinary mVOCs, asthma and essential covariates in the current analyses. After controlling for covariates, we used logistic regression to assess the association between urinary mVOCs and childhood asthma. Then, we examined effect measure modification by child age, gender, race/ethnicity and serum cotinine. 2-Methylhippuric acid (xylene metabolites) (OR: 1.14; 95 % CI: 0.87, 1.59), N-acetyl-S-(benzyl)-l-cysteine (toluene metabolites) (OR: 1.15 95 % CI: 0.76, 1.71), N-acetyl-S-(2-carboxyethyl)-l-cysteine (acrolein metabolites) (OR: 1.09; 95 % CI: 0.61, 1.75), N-acetyl-S-(3-hydroxypropyl)-l-cysteine (acrolein metabolites) (OR: 1.10; 95 % CI: 0.66, 1.80), and N-acetyl-S-(3-hydroxypropyl-1-methyl)-l-cysteine (crotonaldehyde metabolites) (OR: 1.18; 95 % CI: 0.68, 2.01) were weakly associated with the prevalence of asthma in children. Among female children, 2MHA (2-methylhippuric acid) in urine was significantly associated with the prevalence of asthma (OR: 1.81 95 % CI: 1.07, 3.05). At the same time, BMA (N-acetyl-S-(benzyl)-l-cysteine) was significantly associated with the prevalence of asthma in non-Hispanic White (OR:2.09 95 % CI: 0.91, 4.66) and Black (OR:1.90 95 % CI: 0.96, 3.71) children. We found that gender modified the associations between urinary 2MHA and the odds of asthma (interaction term p value = 0.03). Therefore, exposure to VOCs and the development of childhood asthma remains controversial, and the interpretation of these results needs to be treated with caution and should be confirmed in future studies.Therefore, exposure to VOCs and the development of childhood asthma remains controversial, and the interpretation of these results needs to be treated with caution and should be confirmed in future studies.

Volatile organic compounds exposure associated with depression among U.S. adults: Results from NHANES 2011-2020

Volatile organic compounds (VOCs) are important contributors to air pollution. VOCs exposure was associated with various human diseases. Depression is one of the most prevalent mental disorders and poses a serious mental health burden. Although VOCs are neurotoxic and can damage the central nervous system, the association between VOCs exposure and depression remains obscure. Based on data from the National Health and Nutrition Examination Survey, we included 5676 adult individuals and 15 major components of urinary volatile organic compound metabolites (mVOCs). We comprehensively evaluated the potential association between each single urinary mVOC exposure and depressive symptoms using binary logistic and restricted cubic spline regression, whereas the weighted quantile sum regression and least absolute shrinkage and selection operator regression model were used to explore the mixture co-exposure association. The results indicated significantly higher mean concentrations of the 11 urinary mVOC components in the depression group than that in the non-depression group. And 12 mVOC components had a significantly positive association with depression. The overall effect of all 15 mVOCs components was also significantly positive. The corresponding odds ratio was 1.56 (95%CI: 1.2-2.03) in the categorical variable model and the regression coefficient was 0.36 (95%CI: 0.12-0.6) in the numerical variable model. Five urinary mVOCs (URXCYM, URXPHG, URX34 M, URXMB3, and URXAMC) were identified as the most relevant components associated with depression, with 89.06% total weights in the categorical variable model and 89.39% in the numerical variable model. The mVOCs were the biomarkers of VOCs, their concentrations in urine could specifically represent the contents of their metabolic parents in the human body. Considering that the metabolic parents of the above five mVOCs were predominantly acrylonitrile, toluene, styrene, acrylamide, 1,3-Butadiene, and xylenes, our results further indicated that exposure to these VOCs was closely related to depression, and more attention should be paid to the mental health risks of VOCs exposure.

Prenatal exposure to replacement flame retardants and organophosphate esters and childhood adverse respiratory outcomes

BACKGROUND

The association of prenatal exposure to organophosphate esters (OPEs) and replacement brominated flame retardants (RBFRs) with respiratory outcomes has not been previously investigated in humans, despite reports that these chemicals can cross the placenta and alter lung development as well as immune functions.

METHODS

In a cohort of 342 pregnant women recruited between 2003 and 2006 in the greater Cincinnati, Ohio Metropolitan area, we measured indoor dust OPEs and RBFRs at 20 weeks of gestation and urinary OPEs at 16 and 26 weeks of gestation and at delivery. We performed generalized estimating equations and linear mixed models adjusting for covariates to determine the associations of prenatal OPEs and RBFRs exposures with adverse respiratory outcomes in childhood, reported every six months until age 5 years and with lung function at age 5 years. We used multiple informant modeling to examine time-specific associations between maternal urinary OPEs and the outcomes.

RESULTS

Dust concentrations of triphenyl phosphate (TPHP) (RR: 1.40, 95% CI: 1.18-1.66), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (RR: 1.51, 95% CI: 1.23-1.85), and bis(2-ethylhexyl) tetrabromophthalate (RR: 1.57, 95% CI: 1.28-1.94) were associated with higher risk of wheezing during childhood. Dust TPHP concentrations were associated with higher risk of respiratory infections (RR: 1.43, 95% CI: 1.08-1.94), and dust tris-(2-chloroethyl) phosphate concentrations were associated with hay fever/allergies (RR: 1.11, 95% CI: 1.01-1.21). We also found that dust tris-(2-chloroethyl) phosphate loadings were associated with lower lung function. Urinary OPEs mainly at week 16 of gestation tended to be associated with adverse respiratory outcome, while bis(1-chloro-2-propyl) phosphate and diphenyl phosphate at delivery were associated with lower risk of hay fever/allergies.

CONCLUSIONS

In-utero exposure to OPEs and RBFRs may be a risk factor for adverse respiratory outcomes in childhood, depending on the timing of exposure.

Exposure to volatile organic compounds is a risk factor for diabetes: A cross-sectional study

Currently, more studies showed that environmental chemicals were associated with the development of diabetes. However, the effect of volatile organic compounds (VOCs) on diabetes remained uncertain and needed to be studied. This cross-sectional study examined whether exposure to low levels of VOCs was associated with diabetes, insulin resistance (TyG index) and glucose-related indicators (FPG,HbA1c, insulin) in the general population by using the NHANES dataset (2013-2014 and 2015-2016). We analyzed the association between urinary VOC metabolism (mVOCs) and these indicators in 1409 adults by multiple linear regression models or logistic regression models, further Bayesian kernel machine regression (BKMR) models were performed for mixture exposure analysis. The results showed positive associations between multiple mVOCs and diabetes, TyG index, FPG, HbA1c and insulin, respectively. Among them, HPMMA concentration in urine was significantly positively correlated with diabetes and related indicators (TyG index, FPG and HbA1c), and the concentration of CEMA was significantly positively correlated with insulin. The positive association of mVOCs with diabetes and its related indicators was more significant in the female group and in the 40-59 years group. Thus, our study suggested that exposure to VOCs affected insulin resistance and glucose homeostasis, further affecting diabetes levels, which had important public health implications.

The association between exposure to volatile organic compounds and serum lipids in the US adult population

BACKGROUND AND AIM

Epidemiological evidence on the relationship between exposure to volatile organic compounds (VOCs), both single and mixed, and serum lipid levels is limited, and their relationship remains unclear. Our study aimed to investigate the associations of exposure to VOCs with serum lipid levels in the US adult population.

METHODS AND RESULTS

The study examined the association of 16 VOC levels (2-methylhippuric acid, 3- and 4-methylhippuric acid, N-acetyl-S-(2-carbamoylethyl)-L-cysteine, N-acetyl-S-(N-methylcarbamoyl)-L-cysteine, 2-aminothiazoline-4-carboxylic acid, N-acetyl-S-(benzyl)-L-cysteine, N-acetyl-S-(n-propyl)-L-cysteine, N-acetyl-S-(2-carboxyethyl)-L-cysteine, N-acetyl-S-(2-cyanoethyl)-L-cysteine, N-acetyl-S-(3,4-dihydroxybutyl)-L-cysteine, N-acetyl-S-(2-hydroxypropyl)-L-cysteine. N-Acetyl-S-(3-hydroxypropyl)-L-cysteine, mandelic acid, N-acetyl-S-(4-hydroxy-2-butenyl)-L-cysteine, phenylglyoxylic acid and N-acetyl-S-(3-hydroxypropyl-1-methyl)-L-cysteine) with total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL) and high-density lipoprotein cholesterol (HDL) using data from the National Health and Nutrition Examination Survey (NHANES) between 2011 and 2015, and a total of 1410 adults were enrolled. The association was evaluated by Bayesian kernel machine regression (BKMR), multiple linear regression and weighted quantile sum (WQS) regression. In BKMR analysis, exposure to VOCs is positively correlated with levels of TC, TG, and LDL-C. However, statistical significance was observed only for the impact on TG. Our linear regression analysis and WQS regression generally support the BKMR results. Several VOCs were positively associated with serum lipid profiles (e.g., the ln-transformed level of mandelic acid (MA) displayed an increase in estimated changes of 7.01 (95% CIs: 2.78, 11.24) mg/dL for TC level), even after the effective number of tests for multiple testing (P < 0.05).

CONCLUSIONS

Exposure to VOCs was associated with serum lipids, and more studies are needed to confirm these findings.

Assessing volatile organic compounds exposure and chronic obstructive pulmonary diseases in US adults

Background

Volatile organic compounds (VOCs) are a large group of chemicals widely used in People's Daily life. There is increasing evidence of the cumulative toxicity of VOCs. However, the association between VOCs and the risk of COPD has not been reported.

Objective

We comprehensively evaluated the association between VOCs and COPD.

Methods

Our study included a total of 1,477 subjects from the National Health and Nutrition Examination Survey, including VOCs, COPD, and other variables in the average US population. Multiple regression models and smooth-curve fitting (penalty splines) were constructed to examine potential associations, and stratified analyses were used to identify high-risk groups.

Results

We found a positive association between blood benzene and blood o-xylene concentrations and COPD risk and identified a concentration relationship between the two. That is, when the blood benzene and O-xylene concentrations reached 0.28 ng/mL and 0.08 ng/mL, respectively, the risk of COPD was the highest. In addition, we found that gender, age, and MET influence the relationship, especially in women, young people, and people with low MET.

Significance

This study revealed that blood benzene and blood o-xylene were independently and positively correlated with COPD risk, suggesting that long-term exposure to benzene and O-xylene may cause pulmonary diseases, and providing a new standard of related blood VOCs concentration for the prevention of COPD.