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BACKGROUND: Aging is related to an increased risk of morbidity and mortality and is affected by environmental factors. Exposure to polycyclic aromatic hydrocarbons (PAHs) is associated with adverse health outcomes; but the association of such exposure with DNA methylation aging, a novel aging marker, is unclear. OBJECTIVES: Our aim was to investigate the association of PAH exposure with methylation aging. METHODS: We trained and validated a methylation age predictor suitable for Chinese populations using whole blood methylation data in 989 Chinese and 160 Caucasians. We defined two aging indicators: Aage, as methylation age minus chronological age; and aging rate, the ratio of methylation to chronological age. The association of PAH exposure with aging indicators was evaluated using linear regressions in three panels of healthy Chinese participants (N = 539, among the aforementioned 989 Chinese participants) whose exposure levels were assessed by 10 urinary monohydroxy-PAH metabolites. RESULTS: We developed a methylation age predictor providing accurate predictions in both Chinese individuals and Caucasian persons (R = 0.94-0.96, RMSE = 3.8-4.3). Among the 10 urinary metabolites that we measured, 1-hydroxypyrene and 9-hydroxyphenanthrene were associated with methylation aging independently of other OH-PAHs and risk factors; 1-unit increase in 1-hydroxypyrene was associated with a 0.53-y increase in Δage [95% confidence interval (CI): 0.18,0.88; false discovery rate (FDR) FDR = 0.004] and 1.17% increase in aging rate (95% CI: 0.36,1.98; FDR = 0.02), whereas for 9- hydroxyphenanthrene, the increase was 0.54-y for Δage (95% CI: 0.17, 0.91; FDR = 0.004), and 1.15% for aging rate (95% CI: 0.31, 1.99; FDR = 0.02). The association direction was consistent across the three Chinese panels with the association magnitude correlating with the panels' exposure levels; the association was validated by methylation data of purified leukocytes. Several cytosine-phosphoguanines, including those located on FHL2 and ELOVL2, were found associated with both aging indicators and monohydroxy-PAH levels. CONCLUSIONS: We developed a methylation age predictor specific for Chinese populations but also accurate for Caucasian populations. Our findings suggest that exposure to PAHs may be associated with an adverse impact on human aging and epigenetic alterations in Chinese populations. [ABSTRACT FROM AUTHOR]

This study presents the chemical compositional analysis of cow manure in terms of holocellulose (35.97%), lignin (19.02%), and ash (17.47%). Activated carbons (of specific surface area 114 to 893 m2/g, iodine value 219 to 718 mg/g, methylene blue adsorption value 40.5 to 501 mg/g, and ash 16.17% to 22.3%) were prepared from cow manure by using various activator compounds such as potassium carbonate. The results showed that the activation effect of potassium carbonate and zinc chloride was better under the given conditions. The main ash found in the activated carbons was silica, which was reduced to about 3% by washing with sodium hydroxide solution. The prepared activated carbons were used to treat the wastewater from the cow farm and for the pollutant removal that effectively met the discharge standard requirements. These results indicated that the production of activated carbons from cow manure is a promising method for the cleaner production in intensive dairy farms. [ABSTRACT FROM AUTHOR]

Pressure-volume (P-V) curves were measured on shoots of Larix gmelinii and leaves of Fraxinus mandshurica in northeast China to analyze the effects of nonrehydrated, rehydrated, and extended rehydrated treatments on water relations parameters. For L. gmelinii, increasing rehydration time significantly increased the estimate of osmotic potential at full turgor (ψπ100) and at turgor loss point (ψtlp) and decreased the estimate of the relative water content at turgor loss point (RWCtlp), bulk elastic modulus (ε), and symplastic solute content per dry mass (RNs). However, in F. mandshurica, increasing the rehydration time did not significantly change key parameters. The difference in response among these two species relates to the increase in the percent volume of apoplastic water content (AWC) in rehydrated tissues. For L. gmelinii, average AWC was 18.5% in rehydrated and 27.9% in extended rehydration treatments. For F. mandshurica, the average AWC was 4.7% in rehydrated and 4.3% in extended rehydration treatments. In contrast, the AWC value of the nonrehydrated tissue was only 0.7% for L. gmelinii and 2.7% for F. mandshurica. We recommend making P-V curves using unrehydrated tissue whenever possible to avoid potential errors caused by rehydration on the estimates of water relations parameters. [ABSTRACT FROM AUTHOR]

BACKGROUND: Smoking is a risk factor for many human diseases. DNA methylation has been related to smoking, but genome-wide methylation data for smoking in Chinese populations is limited. OBJECTIVES: We aimed to investigate epigenome-wide methylation in relation to smoking in a Chinese population. METHODS: We measured the methylation levels at > 485,000 CpG sites (CpGs) in DNA from leukocytes using a methylation array and conducted a genome-wide meta-analysis of DNA methylation and smoking in a total of 596 Chinese participants. We further evaluated the associations of smoking-related CpGs with internal polycyclic aromatic hydrocarbon (PAH) biomarkers and their correlations with the expression of corresponding genes. RESULTS: We identified 318 CpGs whose methylation levels were associated with smoking at a genome-wide significance level (false discovery rate < 0.05), among which 161 CpGs annotated to 123 genes were not associated with smoking in recent studies of Europeans and African Americans. Of these smoking-related CpGs, methylation levels at 80 CpGs showed significant correlations with the expression of corresponding genes (including RUNX3, IL6R, PTAFR, ANKRD11, CEP135 and CDH23), and methylation at 15 CpGs was significantly associated with urinary 2-hydroxynaphthalene, the most representative internal monohydroxy-PAH biomarker for smoking. CONCLUSION: We identified DNA methylation markers associated with smoking in a Chinese population, including some markers that were also correlated with gene expression. Exposure to naphthalene, a byproduct of tobacco smoke, may contribute to smoking-related methylation. [ABSTRACT FROM AUTHOR]

Rationale: Exposure to polycyclic aromatic hydrocarbons (PAHs) has been associated with adverse effects on the respiratory system. However, the association between internal levels of PAH metabolites and lung function levels remains unclear.Objectives: We investigated the relationships between urinary PAH metabolite concentrations and lung function levels in a general Chinese population.Methods: Lung function and 12 urinary PAH metabolites were measured in 2,747 participants from the Wuhan-Zhuhai cohort in China. Associations between urinary PAH metabolites and lung function were analyzed by linear mixed models. We also investigated associations among urinary PAH metabolite concentrations, traffic exposure time, and dietary PAH exposure.Measurements and Main Results: We found significant associations between increased levels of urinary PAH metabolites and reduced lung function. Each 1-U increase in log-transformed levels of 2-hydroxynaphthalene, 9-hydroxyfluorene, 2-hydroxyfluorene, 4-hydroxyphenanthrene, 9-hydroxyphenanthrene, 3-hydroxyphenanthrene, 1-hydroxyphenanthrene, 2-hydroxyphenanthrene, 1-hydroxypyrene, or total urinary PAH metabolites was associated with a 23.79-, 19.36-, 41.76-, 36.87-, 33.47-, 27.37-, 39.53-, 34.35-, 25.03-, or 37.13-ml reduction in FEV1, respectively (all P < 0.05). Each 1-U increase in 2-hydroxynaphthalene, 2-hydroxyfluorene, 4-hydroxyphenanthrene, 1-hydroxyphenanthrene, 2-hydroxyphenanthrene, or total urinary PAH metabolites was associated with a 24.39-, 33.90-, 27.15-, 28.56-, 27.46-, or 27.99-ml reduction in FVC, respectively (all P < 0.05). The total urinary PAH metabolites concentration was positively associated with both traffic exposure time and dietary PAH exposure among nonsmokers.Conclusions: Total and specific urinary PAH metabolites were associated with lung function reduction in a general Chinese population. Further studies are needed to investigate the potential mechanism by which PAHs induces lung function reduction. [ABSTRACT FROM AUTHOR]

Objective: Reduced pulmonary function is an important predictor of environment-related pulmonary diseases; however, evidence of an association between exposures to various metals from all possible routes and altered pulmonary function is limited. We aimed to investigate the association of various metals in urine with pulmonary function, restrictive lung disease (RLD) and obstructive lung disease (OLD) risks in the general Chinese population. Design: A cross-sectional investigation in the Wuhan cohort population. Setting: A heavily polluted Chinese city. Participants: A total of 2460 community-living Chinese adults from the Wuhan cohort were included in our analysis. Main outcome measures: Spirometric parameters (FVC, forced vital capacity; FEV1, forced expiratory volumes in 1 s; FEV1/FVC ratio), RLD and OLD. Results: The dose-response associations of pulmonary function, and RLD and OLD, with 23 urinary metals were assessed using regression analysis after adjusting for potential confounders. The false discovery rate (FDR) method was used to correct for multiple hypothesis tests. Our results indicated that there were positive dose-response associations of urinary iron with FEV1 and FEV1/FVC ratio, vanadium with FEV1, and copper and selenium with FEV1/FVC ratio, while a negative dose-response association was observed between urinary lead and FEV1/FVC ratio (all p<0.05). After additional adjusting for multiple comparisons, only iron was dose dependently related to FEV1/FVC ratio (FDR adjusted p<0.05). The dose-response association of iron and lead, with decreased and increased chronic obstructive pulmonary disease risk, respectively, was also observed (both p<0.05). Additionally, we found significant association of urinary zinc with RLD and interaction effects of smoking status with lead on FEV1/FVC, and with cadmium on FVC and FEV1. Conclusions: These results suggest that multiple urinary metals are associated with altered pulmonary function, and RLD and OLD prevalences. [ABSTRACT FROM AUTHOR]

Objective: To investigate indoor factors affecting fractional exhaled nitric oxide (FeNO) in community residents. Methods: A total of 2404 adults (865 men, 1539 women, mean age 51.7 ± 13.3 years) were recruited to the study. Factors affecting FeNO were analyzed by multiple linear regression analysis. Results: Participants without a kitchen exhaust fan/hood had higher FeNO (GM: 10.21%, 95% CI: 4.18%-16.59%). Participants engaged in home cooking who used only liquefied petroleum gas had higher FeNO (GM: 5.75%, 95% CI: 0.10%- 11.73%) compared to those using natural gas for residential (home) cooking. Conclusion: Nonuse of a kitchen exhaust fan/hood and use of liquefied petroleum gas among persons engaged in home cooking were associated with higher FeNO levels. [ABSTRACT FROM AUTHOR]

Background: Particulate air pollution has been recognized to be associated with a wide range of adverse health effects, including increased mortality, morbidity, exacerbation of respiratory conditions. However, earlier physiological or pathological changes or long-term bodies' reaction to air pollutants have not been studied in depth in China. The Wuhan-Zhuhai (WHZH) cohort study is designed to investigate the association between air pollutants exposure and physiological or pathological reactions on respiratory and cardiovascular system. Methods/Design: The cohort is a community-based prospective study that includes 4812 individuals aged 18-80 years. The collections of data were conducted from April to May 2011 in Wuhan city and in May 2012 in Zhuhai city. At baseline, data on demographic and socioeconomic information, occupational history, family disease history, lifestyle, cooking mode, daily travel mode, physical activity and living condition have been collected by questionnaires. Participants underwent an extensive physical examination, including anthropometry, spirometry, electrocardiography, and measurements of blood pressure, heart rate, exhaled nitric oxide and carbon monoxide. Potential conditions in the lung, heart, liver, spleen, and skin were synchronously performed. In addition, samples of morning urine, fasting blood serum and plasma were collected during physical health examination. DNA were extracted and were stored at -80°C. Environment concentrations of particulate matter and chemicals were determined for 15 days in each of four seasons. Participants are followed for physiological or pathological changes or incidence of cardiopulmonary diseases every 3 years. Discussion: The results obtained in WHZH cohort study may increase a better understanding of the relationship between particulate air pollution and its components and possible health damages. And the potential mechanisms underlying the development of cardiopulmonary diseases has implications for the development of prevention and treatment strategies. [ABSTRACT FROM AUTHOR]

Objectives To investigate the effects of the urinary metabolite pro les of background exposure to the atmospheric pollutants polycyclic aromatic hydrocarbon (PAH) and Framingham risk score (FRS), which assesses an individual's cardiovascular disease risk, on heart rate variability (HRV). Methods The study conducted from April to May 2011 in Wuhan, China, included 1978 adult residents with completed questionnaires, physical examinations, blood and urine samples, and 5-min HRV indices (including SD of all normal to normal intervals (SDNN), root mean square successive difference (rMSSD), low frequency (LF), high frequency (HF) and their ratio (LF/HF), and total power) obtained from 3-channel Holter monitor. 12 urinary PAH metabolites were measured by gas chromatography-mass spectrometry. FRS was calculated by age, sex, lipid pro les, blood pressure, diabetes and smoking status. Linear regression models were constructed after adjusting for potential confounders. Results Elevated total concentration of hydroxynaphthalene (ΣOHNa) was significantly associated, in a dose-responsive manner, with decreased SDNN and LF/HF (ptrend =0.014 and 0.007, trend respectively); elevated total concentration of hydroxyfluorene (ΣOHFlu) was significantly associated with reduced SDNN, LF and LF/HF (ptrend = 0.027, 0.003, and <0.0001, respectively); and elevated total concentration of all PAH metabolites (ΣOH-PAHs) was associated with decreased LF and LF/HF (ptrend = 0.005 and <0.0001, respectively). Moreover, increasing quartiles of FRS were significantly associated with decreased HRV indices, except LF/HF (all ptrend <0.0001). Interestingly, individuals in low-risk subgroups had greater decreases in SDNN, LF and LF/HF in relation to ΣOH-PAHs, ΣOHNa and ΣOHFlu than those in high-risk subgroups (all p<0.05). Conclusions Environmental PAH exposure may differentially affect HRV based on individual coronary risk profiles. [ABSTRACT FROM AUTHOR]

Diabetes is related to exposure to polycyclic aromatic hydrocarbons (PAHs), inflammation in the body, and housing characters. However, associations of urinary monohydroxy-PAHs (OH-PAHs) or fractional exhaled nitric oxide (FeNO) with diabetes risk in relation to housing characters are unclear. In this study, 2645 individuals were drawn from the baseline survey of the Wuhan-Zhuhai Cohort Study. Associations of diabetes with urinary OH-PAHs or FeNO among cooking participants were estimated using logistic regression models. Among women with self-cooking meals, urinary OH-PAH levels were positively associated with diabetes risk (P < .05); the cooking women with high FeNO (≥25 ppb) had a 59% increase in the risk of diabetes (OR: 1.59, 95% CI: 1.06, 2.38), compared with those with low FeNO (<25 ppb). The cooking women with use of kitchen exhaust fans/hoods had a 52% decrease in the risk of diabetes (OR: 0.48, 95% CI: 0.27, 0.84), compared with those with nonuse of kitchen exhaust fans/hoods. The results indicated that the cooking women had an elevated risk of diabetes, which may be partly explained by an increase in the PAH body burden and higher inflammatory responses. Use of kitchen exhaust fan/hood can be associated with a lower risk of diabetes., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)