Changqing Lin

Estimation of health and economic costs of air pollution over the Pearl River Delta region in China.

The Pearl River Delta region (PRD) is the economic growth engine of China and also one of the most urbanized regions in the world. As a two-sided sword, rapid economic development causes air pollution and poses adverse health effects to the citizens in this area. This work estimated the negative health effects in the PRD caused by the four major ambient pollutants (SO2, NO2, O3 and PM10) from 2010 to 2013 by using a log linear exposure-response function and the WRF-CMAQ modeling system. Economic loss due to mortality and morbidity was evaluated by the value of statistical life (VSL) and cost of illness (COI) methods. The results show that the overall possible short-term all-cause mortality due to NO2, O3 and PM10 reached the highest in 2013 with the values being 13,217-22,800. The highest total economic loss, which ranged from 14,768 to 25,305million USD, occurred in 2013 and was equivalent to 1.4%-2.3% of the local gross domestic product. The monthly profile of cases of negative health effects varied by city and the types of ambient pollutants. The ratio of mortality attributed to air pollutants to total population was higher in urban areas than in rural areas. People living in the countryside should consider the possible adverse health effects of urban areas before they plan a move to the city. The results show that the health burden caused by the ambient pollutants over this region is serious and suggest that tighter control policies should be implemented in the future to reduce the level of air pollution.

Assessing Long-Term Trend of Particulate Matter Pollution in the Pearl River Delta Region Using Satellite Remote Sensing

Serious particulate matter (PM) pollution problems in many polluted regions of China have been frequently reported in recent years. Long-term exposure to ambient PM pollution is significantly associated with adverse health effects. Characterizing the long-term trends and variation in PM pollution is a basic requirement for evaluating long-term exposure and for guiding future policies to reduce the effects of air pollution on health. However, long-term, ground-based PM measurements are only available at a few fixed stations. In this study, an algorithm is developed and validated to estimate PM concentrations based on the satellite atmospheric optical depth with 1 km spatial resolution. The long-term trends of PM10 concentrations in the entire Pearl River Delta (PRD) region and different cities are quantified and discussed. From 2001 to 2013, the PM10 pollution of the entire PRD region was dominated by a decreasing trend of -0.15 ± 0.23 μg/m(3)·yr. This decreasing PM10 trend was apparent over 75% of the PRD area, with the most significant decreases observed in the center of the region. However, the remaining 25%, mostly located in the outskirts of the region, showed an increasing PM10 trend. This overall decreasing trend indicates the effectiveness of the control measures applied in the past decade for the primary pollutants.

Assessment of health burden caused by particulate matter in southern China using high-resolution satellite observation

As the major engine of economic growth in China, the Pearl River Delta (PRD) region is one of the most urbanized regions in the world. Rapid development has brought great wealth to its citizens; however, at the same time, increasing emissions of ambient pollutants from vehicles and industrial combustions have caused considerable air pollution and negative health effects for the regions residents. In this study, the concentration response function method was applied together with satellite-retrieved particulate matter (PM10 and PM2.5) concentration data to estimate the health burden caused by this pollutant from 2004 to 2013. The value of statistical life was used to calculate the economic loss due to the negative health effects of particulate matter pollution. Our results show that in the whole PRD region, the estimated number of deaths from the four diseases attributable to PM2.5 was the highest in 2012, at 45,000 (19,000-61,000); the number of all-cause hospital admissions due to PM10 was the highest in 2013, reaching up to 91,000 (0-270,000) (excluding Hong Kong). Among the 10 cities, the capital city Guangzhou suffered the most from ambient particulate matter pollution and had the highest mortality and morbidity over the 10years. The cost of mortality in this region was the highest in 2012, at 46,000 million USD, or around 6.1% of local total gross domestic product (GDP). The positive spatial relationship between the degree of urbanization and the particulate matter concentration proves that the urbanization process does worsen air quality and hence increases the health risks of local urban citizens. It is recommended that local governments further enhance their control policies to better guarantee the health and wealth benefits of local residents.

Satellite-based estimates of long-term exposure to fine particulate matter are associated with C-reactive protein in 30 034 Taiwanese adults

Abstract Background Particulate matter (PM) air pollution is associated with the risk of cardiovascular morbidity and mortality. However, the biological mechanism underlying the associations remains unclear. Atherosclerosis, the underlying pathology of cardiovascular disease, is a chronic inflammatory process. We therefore investigated the association of long-term exposure to fine PM (PM2.5) with C-reactive protein (CRP), a sensitive marker of systemic inflammation, in a large Taiwanese population. Methods Participants were from a large cohort who participated in a standard medical examination programme with measurements of high-sensitivity CRP between 2007 and 2014. We used a spatiotemporal model to estimate 2-year average PM2.5 exposure at each participant’s address, based on satellite-derived aerosol optical depth data. General regression models were used for baseline data analysis and mixed-effects linear regression models were used for repeated data analysis to investigate the associations between PM2.5 exposure and CRP, adjusting for a wide range of potential confounders. Results In this population of 30 034 participants with 39 096 measurements, every 5 μg/m3 PM2.5 increment was associated with a 1.31% increase in CRP [95% confidence interval (CI): 1.00%, 1.63%) after adjusting for confounders. For those participants with repeated CRP measurements, no significant changes were observed between the first and last measurements (0.88 mg/l vs 0.89 mg/l, P = 0.337). The PM2.5 concentrations remained stable over time between 2007 and 2014. Conclusions Long-term exposure to PM2.5 is associated with increased level of systemic inflammation, supporting the biological link between PM2.5 air pollution and deteriorating cardiovascular health. Air pollution reduction should be an important strategy to prevent cardiovascular disease.

Particulate matter air pollution, physical activity and systemic inflammation in Taiwanese adults

BACKGROUND The protective effects of physical activity (PA) against chronic disease can be partially ascribed to its anti-inflammatory effects. On the other hand, long-term exposure to particulate matter with an aerodynamic diameter less than 2.5μm (PM2.5) may induce systemic inflammation. OBJECTIVE To investigate the joint effects of habitual PA and long-term exposure to PM2.5 on systemic inflammation in a large cohort of Taiwanese adults. METHODS We studied 359,067 adult participants from a cohort consisting of Taiwanese residents who participated in a standard medical examination program from 2001 to 2014. Peripheral white blood cell (WBC) and differential counts were measured as indicators of systemic inflammation. Two-year average concentration of PM2.5 was estimated at each participants address using a satellite-based spatio-temporal model. Habitual PA level was assessed by questionnaire (inactive, low, moderate and high). Mixed-effects linear regression model was used to examine the associations of WBC counts with PM2.5 and PA. RESULTS Compared with inactive participants, those with low, moderate or high PA levels had 0.36% [95% confidence interval (CI): 0.31%, 0.41%], 0.70% (95%CI: 0.65%, 0.76%) and 1.16% (95%CI: 1.11%, 1.22%) lower WBC counts, respectively, after adjusting for PM2.5 exposure and a wide range of confounders. Long-term PM2.5 exposure was associated with increased WBC counts at all PA levels. Analyses for differential counts generated similar results. No significant interaction was observed between PA and PM2.5 exposure (P for interaction=0.59). CONCLUSIONS Habitual PA was associated with statistically significant lower markers of systemic inflammation across different levels of PM2.5. Effects of PA and PM2.5 exposure on systemic inflammation are independent.

Effect of long-term exposure to fine particulate matter on lung function decline and risk of chronic obstructive pulmonary disease in Taiwan: a longitudinal, cohort study

BACKGROUND Information on the effects of long-term exposure to fine particulate matter with an aerodynamic diameter of 2·5 μm or less (PM2·5) on lung health is scarce. We aimed to investigate the associations between long-term exposure to PM2·5, lung function, and chronic obstructive pulmonary disease (COPD) in a large-scale longitudinal cohort. METHODS We included 285 046 participants aged 20 years or older from the Taiwan MJ Health Management Institution cohort, who were recruited between 2001 and 2014 and had spirometric tests during the medical examination visit. We used a satellite-based spatiotemporal model to estimate the 2-year average ground concentration of PM2·5 (for the calendar year of each participants medical examination and for the previous year) at each participants address. We used the generalised linear mixed model to examine the associations between PM2·5 concentrations and lung function and the Cox proportional hazard regression model with time-dependent covariates to investigate the PM2·5 effects on COPD development. FINDINGS Every 5 μg/m3 increment in PM2·5 was associated with a decrease of 1·18% for forced vital capacity (FVC), 1·46% for forced expiratory volume in 1 s (FEV1), 1·65% for maximum mid-expiratory flow (MMEF), and 0·21% for FEV1:FVC ratio. The decrease accelerated over time. Additional annual declines were observed for FVC (0·14%), FEV1 (0·24%), MMEF (0·44%), and FEV1:FVC ratio (0·09%). Compared with the participants exposed to the first quartile of PM2·5, participants exposed to the fourth, third, and second quartiles of PM2·5 had a hazard ratio of 1·23 (95% CI 1·09-1·39), 1·30 (1·16-1·46), and 1·39 (1·24-1·56) for COPD development, respectively. INTERPRETATION Long-term exposure to ambient PM2·5 is associated with reduced, and faster declines in, lung function. Long-term exposure to ambient PM2·5 is also associated with an increased risk of the incidence of COPD. This study reinforces the urgency of global strategies to mitigate air pollution for improvement of pulmonary health and prevention of COPD. FUNDING Environmental Health Research Fund of the Chinese University of Hong Kong and PhD Studentship of the Chinese University of Hong Kong.

Exposure to ambient fine particulate matter and semen quality in Taiwan

Objectives Environmental exposure to chemicals has been considered a potential factor contributing to deteriorated semen quality. However, previous literature on exposure to air pollution and semen quality is inconsistent. We therefore investigated the health effects of short-term and long-term exposure to fine particulate matter (PM2.5) on semen quality in Taiwanese men from the general population. Methods A cross-sectional study was conducted among 6475 male participants aged 15–49 years who participated in a standard medical examination programme in Taiwan between 2001 and 2014. Semen quality was assessed according to the WHO 1999 guidelines, including sperm concentration, total motility, progressive motility and morphology. Three-month and 2-year average PM2.5 concentrations were estimated at each participant’s address using a spatiotemporal model based on satellite-derived aerosol optical depth data. Multivariable linear and logistic regressions were used to examine the associations between PM2.5 and semen quality. Results A robust association was observed between exposure to PM2.5 and decreased normal morphology. Every increment of 5 µg/m3 in 2-year average PM2.5 was significantly associated with a decrease of 1.29% in sperm normal morphology and a 26% increased risk of having the bottom 10% of sperm normal morphology, after adjusting for a wide range of potential confounders (p<0.001). On the other hand, an increment of 5 µg/m3 in 2-year average PM2.5 was associated with an increase of 1.03×106/mL in sperm concentration and a 10% decreased risk of being the bottom 10% of sperm concentration (both p<0.001). Similar results were found for 3-month PM2.5. Conclusions Exposure to ambient PM2.5 air pollution is associated with a lower level of sperm normal morphology and a higher level of sperm concentration.

Long-term exposure to ambient particulate matter (PM2.5) is associated with platelet counts in adults

BACKGROUND The prothrombotic effects of particulate matter (PM) may underlie the association of air pollution with increased risks of cardiovascular disease. This study aimed to investigate the association between long-term exposure to PM with an aerodynamic diameter ≤2.5 μm (PM2.5) and platelet counts, a marker of coagulation profiles. METHODS The study participants were from a cohort consisting of 362,396 Taiwanese adults who participated in a standard medical examination program between 2001 and 2014. Platelet counts were measured through Complete Blood Count tests. A satellite-based spatio-temporal model was used to estimate 2-year average ambient PM2.5 concentration at each participants address. Mixed-effects linear regression models were used to investigate the association between PM2.5 exposure and platelet counts. RESULTS This analysis included 175,959 men with 396,248 observations and 186,437 women with 397,877 observations. Every 10-μg/m3 increment in the 2-year average PM2.5 was associated with increases of 0.42% (95% CI: 0.38%, 0.47%) and 0.49% (95% CI: 0.44%, 0.54%) in platelet counts in men and women, respectively. A series of sensitivity analyses, including an analysis in participants free of cardiometabolic disorders, confirmed the robustness of the observed associations. Baseline data analyses showed that every 10-μg/m3 increment in PM2.5 was associated with higher risk of 17% and 14% of having elevated platelet counts (≥90th percentile) in men and women, respectively. CONCLUSIONS Long-term exposure to PM2.5 appears to be associated with increased platelet counts, indicating potential adverse effects on blood coagulability.

PM2·5 concentration and elderly tuberculosis: analysis of spatial and temporal associations

Abstract Background China periodically has severe ambient particulate matter (PM) pollution, which could cause compromised pulmonary immunity in the population and result in high cardio-respiratory morbidity and mortality. Acknowledging the highly prevalent latent tuberculosis in elderly people, we hypothesise that they are more prone to tuberculosis reactivation in the presence of air pollution. Methods We examined the spatial and temporal association between PM 2·5 concentration and the number of reported cases of tuberculosis in elderly people aged 65 years and older in Hong Kong. Tuberculosis notification data in 2005–07 were collected from the Chinese Governments TB and Chest Service. Monthly and annual PM 2·5 concentration by geographical subdistrict (DCCA) for the corresponding years were derived from satellite images. Age–gender standardised notification rate (SNR) of tuberculosis cases in elderly people was calculated per DCCA/time. Their temporal association with PM 2·5 was examined by dynamic linear regression in R, and spatial association by spatial regression in GeoDa. Findings Among 17 294 new cases of tuberculosis reported in 2005–07, 6879 (40%) cases were in elderly people (2·69 men for every woman). The mean monthly SNR for elderly men was 35·4 per 100 000 persons (range 25·2–45·3), and the mean of mean PM 2·5 in DCCA was 30·5 μg/m 3 (16·1–47·1). Temporally, the SNR for elderly men was associated with PM 2·5 in lag 0, lag −1 (ie, moving PM 2·5 1 month earlier), and lag −4 to −6 months, with the most significant positive association at lag −6 months. However, no temporal association between the SNR for elderly women and PM 2·5 was observed. Spatially, the SNR was associated with PM 2·5 for elderly men in all 3 years but only for women in 2005. Interpretation We detected spatial and temporal associations between cases of tuberculosis in elderly men and PM 2·5 . Tuberculosis reactivation might have occurred after exposure to high PM 2·5 in the environment, as inferred from the lag interval of 6 months revealed in our results. The discrepancy between sexes and the effects of potential confounders such as sunshine duration, income level, and locality would need to be further investigated. Funding Research Grants Council under Theme-based Research Scheme (T32-102/14N).

Analysis of the adverse health effects of PM2.5 from 2001 to 2017 in China and the role of urbanization in aggravating the health burden

In this study, the trend of PM2.5 concentrations and its adverse health effects in China from 2001 to 2017 are estimated utilizing 1-km high-resolution annual satellite-retrieved PM2.5 data. PM2.5 concentrations for most of the provinces/cities remained stable from 2001 to 2012; however, following the issue of the Air Pollution Prevention and Control Action Plan (APPCAP) by the central government of China, a dramatic decrease in PM2.5 concentrations from 2013 to 2017 occurred. Premature mortality caused by PM2.5 dropped from 1,078,800 in 2014 to 962,900 in 2017. The PM2.5 caused 17-year average mortality ranges from 3800 in Hainan Province to 124,800 in Henan Province. The health cost benefits gained by the reduction of PM2.5 pollution amounted to US