Junfeng Zhang

The objective of this paper is to conduct an integrated analysis of the energy, greenhouse gas, and air quality impacts of a new type of boiler briquette coal (BB-coal) in contrast to those of the raw coal from which the BB-coal was formulated (R-coal). The analysis is based on the source emissions data and other relevant data collected in the present study and employs approaches including the construction of carbon, energy, and sulfur balances. The results show that replacing R-coal with BB-coal as the fuel for boilers such as the one tested would have multiple benefits, including a 37% increase in boiler thermal efficiency, a 25% reduction in fuel demand, a 26% reduction in CO2 emission, a 17% reduction in CO emission, a 63% reduction in SO2 emission, a 97% reduction in fly ash and fly ash carbon emission, a 22% reduction in PM2.5 mass emission, and a 30% reduction in total emission of five toxic hazardous air pollutant (HAP) metals contained in PM10. These benefits can be achieved with no changes in boiler hardware and with a relatively small amount of tradeoffs: a 30% increase in PM10 mass emission and a 9-16% increase in fuel cost.

BACKGROUND/AIM: Melatonin is a free radical scavenger and an anti-inflammatory biomolecule. Air pollution exposure has been associated with increased inflammatory responses. We hypothesize that endogenous melatonin plays a role in inflammatory responses to air pollution exposure. METHODS: We tested this hypothesis in a cohort of 53 healthy adults (22-52 years old, 16 women), none of whom were on melatonin supplementation. Early morning urine and fasting blood were collected from each participant longitudinally up to three times. We analyzed urinary 6-sulfatoxymelatonin (aMT6s), as a surrogate of circulating melatonin, and pro- and anti-inflammatory cytokines in the plasma samples. Indoor and outdoor air pollutants were measured and combined with participants' time-activity patterns to calculate personal exposure to O3, PM2.5, NO2, and SO2 averaged over 12-hour, 24-hour, 1-week, and 2-week periods prior to biospecimen collection, respectively. Linear mixed-effects models were used to examine the relationships among urinary aMT6s, personal pollutant exposure, and plasma cytokines. A mediation analysis was conducted to examine the role of aMT6s in the relationships between pollutant exposures and inflammatory cytokines. RESULTS: One interquartile range (4.2 ppb) increase in 2-week O3 exposure was associated with a -26.2% (95% CI: -43.9% to -2.8%) decrease in aMT6s. Within the range of endogenous aMT6s concentrations (0.5-53.0 ng/ng creatinine) across the participants, increased aMT6s was associated with decreased pro-inflammatory cytokines including IL-1β, IL-8, IL-17A, IFN-γ, and TNF-α. These cytokines were significantly and positively associated with 2-week average O3 exposure. Furthermore, 7.4% to 17.4% of the O3-cytokine associations were mediated by aMT6s. We did not find similar effects for the other pollutants. CONCLUSIONS: Pro-inflammatory responses to O3 exposure in the preceding 2 weeks partly resulted from the depletion of endogenous melatonin by O3.

BACKGROUND:The importance of airway mechanics has been increasingly recognized in pediatric asthma. However, no studies have examined responses of airway mechanics to air pollution exposure in asthmatic children. METHODS:In this panel study involving indoor air filtration manipulation that created a large gradient of personal exposure to PM2.5, the airway mechanics and lung function of 43 asthmatic children 5-13 years old in a suburb of Shanghai were measured four times within 3 consecutive months. Concentrations of indoor and outdoor PM2.5 and ozone were coupled with individual time-activity data to calculate personal exposures. Linear mixed effects models were used to examine the relationships of personal exposure with indicators of airway mechanics and lung function, respectively. RESULTS:An interquartile range (IQR) increase in 24-hour average PM2.5 personal exposure (30.3 µg/m3) in the prior day was associated with significant increases in small airway resistance (R5-R20) of 15.8%, total airway resistance (R5) of 6.3%, and airway inflammation (FeNO) of 9.6%. These associations were stronger in children with lower blood eosinophil counts (<450/µL). No significant associations were found between personal PM2.5 exposure and lung function. Low-level ozone exposure (daily maximum 8-hour exposure range 1.1-56.4 ppb) was not significantly associated with any of the outcomes. CONCLUSION:Changes in personal PM2.5 exposure, partly enhanced by air filtration, were associated with significant changes in airway resistance and inflammation in children with asthma. These findings suggest the importance of reducing PM2.5 exposure, via personal air quality management, in improving airflow limitation in the airways, especially the small airways.

RATIONALE:Associations between urban (outdoor) airborne particulate matter (PM) exposure and TB and potential biological mechanisms are poorly explored. OBJECTIVES:To examine whether in vivo exposure to urban outdoor PM in Mexico City and in vitro exposure to urban outdoor PM2.5 (< 2.5 µm median aerodynamic diameter) alters human host immune cell responses to Mycobacterium tuberculosis. METHODS:Cellular toxicity (flow cytometry, proliferation assay (MTS assay)), M. tuberculosis and PM2.5 phagocytosis (microscopy), cytokine-producing cells (Enzyme-linked immune absorbent spot (ELISPOT)), and signalling pathway markers (western blot) were examined in bronchoalveolar cells (BAC) and peripheral blood mononuclear cells (PBMC) from healthy, non-smoking, residents of Mexico City (n=35; 13 female, 22 male). In vivo-acquired PM burden in alveolar macrophages (AM) was measured by digital image analysis. MEASUREMENTS AND MAIN RESULTS:In vitro exposure of AM to PM2.5 did not affect M. tuberculosis phagocytosis. High in vivo-acquired AM PM burden reduced constitutive, M. tuberculosis and PM-induced interleukin-1β production in freshly isolated BAC but not in autologous PBMC while it reduced constitutive production of tumour necrosis factor-alpha in both BAC and PBMC. Further, PM burden was positively correlated with constitutive, PM, M. tuberculosis and purified protein derivative (PPD)-induced interferon gamma (IFN-γ) in BAC, and negatively correlated with PPD-induced IFN-γ in PBMC. CONCLUSIONS:Inhalation exposure to urban air pollution PM impairs important components of the protective human lung and systemic immune response against M. tuberculosis. PM load in AM is correlated with altered M. tuberculosis-induced cytokine production in the lung and systemic compartments. Chronic PM exposure with high constitutive expression of proinflammatory cytokines results in relative cellular unresponsiveness.

PURPOSE:Specific medical and living conditions in rural China may predispose people there to a poor quality of life. This study aimed to evaluate factors affecting the quality of life among married women in rural China. METHODS:This cross-sectional study was conducted in rural areas of Liaoning Province in China. Out of the 3900 married women, 3163 (81%) completed the questionnaire survey. Quality of life was assessed using the WHOQOL-BREF scale. Sociodemographic factors, such as monthly income, and living and health conditions, such as left-behind status, stress (quantified by the Perceived Stress Scale), and coping styles (assessed by the Simplified Coping Style Questionnaire) were collected through self-reported questionnaires. Hierarchical multiple regression was used to explore the factors related to quality of life. RESULTS:The mean scores of quality of life were 14.08 ± 2.27 for the domain of physical health, 11.78 ± 2.28 for psychological health, 13.07 ± 2.69 for social relationships, and 12.26 ± 2.67 for environmental conditions. Older age, having chronic diseases, being left-behind, sense of marriage insecurity, and stress were all negatively associated with quality of life scores, whereas a higher monthly income was associated with higher scores. Coping styles could be moderating factors in the relationship between stress and quality of life. CONCLUSIONS:Overall, married women living in rural China had relatively low scores for quality of life. Improving family income, providing access to affordable and high-quality medical care, facilitating couple communication, and promoting active coping styles could be intervention strategies to improve the quality of life of these rural residents.