[Study on revision of standard limits for nitrogen dioxide in "Standards for indoor air quality（GB/T 18883-2022）" in China].

Nitrogen dioxide (NO2) is an important indoor air pollutant, with both outdoor and indoor sources contributing to indoor NO2 exposure levels. Considering the association of high NO2 exposure with adverse health effects, the Standards for indoor air quality (GB/T 18883-2022) have been revised to further restrict indoor NO2 limit values. The 1-h average concentration limit value for NO2 has been reduced from 0.24 mg/m3 to 200 µg/m3.This study analyzed the technical contents related to the determination of the limits of indoor NO2 in Standards for Indoor Air Quality (GB/T 18883-2022), including source, exposure level, health effects, and the process and evidence basis for determining the limit value. It also proposed prospects for the direction for the implementation of the indoor NO2 standard.

[A panel study on the acute respiratory effects of ambient particles of different sizes on children in Shanghai].

Objective: To explore the association between size-fractionated particle number concentrations (PNC) and respiratory health in children. Methods: From November 2018 to June 2019, there were 65 children aged 6-9 years from an elementary school in shanghai recruited in this panel study with three rounds of follow-up. The forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), and exhaled nitric oxide (FeNO) levels were measured and buccal mucosa samples of children were collected at each follow-up visit. The level of PNC, temperature and humidity of the elementary school was monitored from 3 days before each physical examination to the end of the physical examination. The linear mixed effects model was used to analyze the association between PNC and indicators of respiratory health in children. Results: Linear mixed effects model analysis revealed that, at lag 2 day, an interquartile range increase in PNC for particles measuring 0.25-0.40 µm was associated with the absolute changes in FVC, FEV1 and abundance-based coverage estimator (ACE) about -60.15 ml (95%CI:-88.97 ml, -31.32 ml), -34.26 ml (95%CI:-63.22 ml, -5.31 ml), -6.00 (95%CI:-9.15, -2.84) and percentage change in FeNO about 12.10% (95%CI: 3.05%, 21.95%), respectively. These adverse health effects increased with the decrease of particle size. Conclusion: The short-term exposure to particulate matter is associated with reduced lung function, buccal microbe diversity and higher airway inflammation level among children. These adverse health effects may increase with the decrease of particle size.

[Research progress of ambient air pollution and human health in China].

As one of the major environmental and health problems in China, ambient air pollution has attracted substantial public concerns. This paper reviews the current evidence on air pollution and population health in China, including acute health effect studies, chronic health effect studies, disease burden, and interventions studies. Future research directions are also discussed.

[Impact of fine particulate matters on the daily number of emergency visits and outpatient visits of 5 hospitals in Beijing, Shanghai, and Guangzhou, 2013-2015].

Objective: To explore the effect of fine particulate matters (PM(2.5)) exposure on emergency visits and outpatient visits of 5 hospitals in Beijing, Shanghai and Guangzhou from 2013 to 2015. Methods: Using convenient sampling method, 5 general hospitals in Beijing, Shanghai and Guangzhou were selected which included Beijing hospital, China-Japan friendship hospital, Xinhua hospital affiliated to Shanghai jiaotong University School of Medicine, the liwan hospital of the third affiliated hospital and the first affiliated hospital of Guangzhou Medical University. The emergency and outpatient data, air pollution monitoring data and meteorological data were collected from January 1, 2013 to December 31, 2015. A generalized additive model was used to analyze the effect of PM(2.5) exposure on daily hospital emergency and outpatient visits, and Meta analysis was used to obtain the combined effect value. Results: The number of emergency and outpatient visits of 5 hospitals was 1 378 501 and 18 139 779 in total, respectively. The mean±SD of PM(2.5) exposures in Beijing hospital, China-Japan friendship hospital, Xinhua hospital affiliated to Shanghai jiaotong University School of Medicine, the liwan hospital of the third affiliated hospital and the first affiliated hospital of Guangzhou Medical University were (81.8±68.7), (83.2±69.7), (54.4±34.1), (43.5±24.8) µg/m(3), respectively. Results of single pollutant model analysis showed that 0-1 day lag concentrations of PM(2.5) had the largest effect on emergency visits and outpatient visits. For a 10 µg/m(3) increase of PM(2).5 concentration, excess risk (ER) (95%CI) of emergency and outpatient visits was 0.56% (0.14%, 0.99%) and0.63% (0.07%, 1.19%), respectively. After adjusting for O(3), NO(2), SO(2), and CO, for a 10 µg/m(3) increase of PM(2.5) concentrations, the ER (95%CI) of emergency visits was 0.50% (0.10%, 0.90%), 0.34% (-0.02%, 0.69%), 0.36% (0.02%, 0.69%) and 0.56% (0.10%, 1.03%), respectively and the ER (95% CI) of outpatient visits was 0.65% (0.08%, 1.21%), 0.29% (-0.17%, 0.75%), 0.48% (-0.06%, 1.03%) and 0.48%(-0.02%, 0.99%), respectively. Conclusion: Our results suggested that PM(2.5) exposure can increase emergency and outpatient visits of 5 hospitals in Beijing, Shanghai and Guangzhou.

[Review on methods in the disease burden assessment attributable to household air pollution].

In the past decades, people's work and life styles have dramatically changed during the rapid economic development and urbanization in China. A national survey reported that Chinese adults spend an average of 81% of daily time in indoor environment. Exposure to indoor air pollution plays key roles for human health but is likely to be neglected due on the relatively lower concentration levels and lower awareness among common people. Till now, published studies focus more on the pollution levels or the toxicological effects of indoor air pollutants but there is a lack of disease burden assessment attributable to indoor air pollution. In this review, several international studies were introduced on the disease burden estimation attributable to indoor air pollution, as well as the estimation methods. The current situation of national study was also reviewed. The strengths and limitations of the representative international studies were discussed. This review is helpful in providing data to guide the research on disease burden assessment attributable to indoor air pollution in China, and further helps to prioritize the indoor air pollution control based on disease burden ranking among pollutants and motivate public policies to protect the public health.

[The impact of ambient fine particulate matter on the blood pressure of an urban population in Shanghai, China: a panel study].

OBJECTIVE: To investigate the impact of particulate matter 2.5 (PM2.5) on the blood pressure of urban residents in Shanghai, China. METHODS: A panel study was conducted from May 27(th) to June 5(th) 2014 in a cohort of 30 adults in an urban community. Participants were 50-80 years old, had lived in the community for at least 5 years, and had a good health status. Key exclusion criteria were current smoking, smoking during the last 3 years, passive smoking, alcohol consumption, and severe cardiopulmonary disease. A total of 28 participants were eligible. Information on demographic characteristics, including of age, sex, height, weight, education, income and chronic comorbidities were collected. Participants were requested to have six weekly blood pressure measurements. Real-time concentrations of PM2.5 and gaseous pollutants were obtained from a nearby air quality monitor during 40 d. Pearson correlation was applied to analyze the correlation between PM2.5 and SO2, NO2, CO and O3. Linear mixed models were applied to analyze the association between PM2.5 and blood pressure, after controlling for time-related trends, day of the week, mean temperature, relative humidity and individual characteristics. RESULTS: The mean systolic and diastolic blood pressure was (124.0±15.0) mmHg (1 mmHg=0.133 kPa) and (74.0±7.7) mmHg, respectively. At 24 h before blood pressure measurement, the mean PM2.5, SO2, NO2, O3 and CO concentration were (8.3±4.9), (46.6±12.9) , (79.2±27.4) µg/m(3) and (0.8±0.2) mg/m(3). The Pearson correlation coefficient R, between PM2.5 and O3, SO2, NO2 and CO was 0.79, 0.59, 0.34 and 0.45, respectively, with corresponding P-values of <0.001, 0.006, 0.012 and 0.009, respectively. The significant correlation between PM2.5 and systolic blood pressure occurred at lag 1 day, was strongest at lag 3 day, but attenuated thereafter. A 10 µg/m(3) increase in 3-day average concentrations of PM2.5 was associated with changes of 1.86 (95%CI: 0.62-3.09) mmHg in systolic blood pressure and -0.05 (95%CI: 0.59-0.50) mmHg in diastolic blood pressure. CONCLUSION: Short-term exposure to PM2.5 may significantly elevate the systolic blood pressure of urban residents in Shanghai.

[Progress and future perspective of epidemiological research of air pollution and climate change in the context of achieving carbon peaking and carbon neutrality goals].

Climate change is the great health challenge for human beings in the 21st century. Air pollution is also an important public health problem worldwide. China announced the climate commitment to achieve carbon peaking by 2030 and carbon neutrality by 2060. Achieving these goals would not only have far-reaching effects on air pollution control and climate change, but also improve the population health in China. Air pollution and climate change epidemiology are important aspects of environmental epidemiology. In this paper, we discuss the current status and future development of epidemiological research of air pollution and climate change in the context of achieving carbon peaking and carbon neutrality goals to provide ideas and suggestions for environmental and health studies in the future.

Reduced prostate cancer risk with green tea and epigallocatechin 3-gallate intake among Hong Kong Chinese men.

BACKGROUND: In vitro and in vivo studies suggested that polyphenol epigallocatechin 3-gallate (EGCG) in tea may have anti-carcinogenic effect on prostate cells, but this protective effect has less been examined in epidemiology studies. We aimed to investigate the association between prostate cancer (PCA) risk and habitual green tea intake among Chinese men in Hong Kong; meanwhile, the relationship with EGCG was also explored. METHODS: We consecutively recruited 404 PCA cases and 395 controls from the same hospital who had complete data on habitual tea consumption, including green, oolong, black and pu'er tea. We reconstructed the level of EGCG intake according to a standard questionnaire and the analytic values for EGCG extracted from the literature published by Lin et al. in 2003. We calculated odds ratios (ORs) for tea consumption and EGCG intake using unconditional multiple logistic regression, and examined their exposure--response relationships with PCA risk. RESULTS: A total of 32 cases and 50 controls reported habitual green tea drinking, showing an adjusted OR of 0.60 (95% confidence interval (CI): 0.37, 0.98). A moderate excess risk was observed among the habitual pu'er tea drinkers (OR=1.44, 95% CI: 1.02, 1.91). A significantly lower intake of EGCG was observed among cases (54.4 mg) than the controls (72.5 mg), which resulted in an inverse gradient of PCA risk with the increasing intake of EGCG (test for trend, P=0.015). CONCLUSION: PCA risk among Chinese men in Hong Kong was inversely associated with green tea consumption and EGCG intake, but these results need to be replicated in larger studies.