# Environmental Health

2007
Chris P Nielsen and Mun S Ho. 2007. “Summary for policy.” In Clearing the air: The health and economic damages of air pollution in China, edited by Mun S Ho and Chris P Nielsen. Cambridge, MA: MIT Press. Publisher's VersionAbstract

An interdisciplinary, quantitative assessment of the health and economic costs of air pollution in China, and of market-based policies to build environmental protection into economic development.

China's historic economic expansion is driven by fossil fuels, which increase its emissions of both local air pollutants and greenhouse gases dramatically. Clearing the Air is an innovative, quantitative examination of the national damage caused by China's degraded air quality, conducted in a pathbreaking, interdisciplinary U.S.-China collaboration. Its damage estimates are allocated by sector, making it possible for the first time to judge whether, for instance, power generation, transportation, or an unexpected source such as cement production causes the greatest environmental harm. Such objective analyses can reset policy priorities.

Clearing the Air uses this information to show how appropriate "green" taxes might not only reduce emissions and health damages but even enhance China's economic growth. It also shows to what extent these same policies could limit greenhouse gases, suggesting that wealthier nations have a responsibility to help China build environmental protection into its growth.

Clearing the Air is written for diverse readers, providing a bridge from underlying research to policy implications, with easily accessible overviews of issues and summaries of the findings for nonspecialists and policymakers followed by more specialized, interlinked studies of primary interest to scholars. Taken together, these analyses offer a uniquely integrated assessment that supports the book's economic and policy recommendations.

Chris P Nielsen and Mun S Ho. 2007. “Summary for research.” In Clearing the air: The health and economic damages of air pollution in China, edited by Mun S Ho and Chris P Nielsen. Cambridge, MA: MIT Press. Publisher's VersionAbstract

An interdisciplinary, quantitative assessment of the health and economic costs of air pollution in China, and of market-based policies to build environmental protection into economic development.

China's historic economic expansion is driven by fossil fuels, which increase its emissions of both local air pollutants and greenhouse gases dramatically. Clearing the Air is an innovative, quantitative examination of the national damage caused by China's degraded air quality, conducted in a pathbreaking, interdisciplinary U.S.-China collaboration. Its damage estimates are allocated by sector, making it possible for the first time to judge whether, for instance, power generation, transportation, or an unexpected source such as cement production causes the greatest environmental harm. Such objective analyses can reset policy priorities.

Clearing the Air uses this information to show how appropriate "green" taxes might not only reduce emissions and health damages but even enhance China's economic growth. It also shows to what extent these same policies could limit greenhouse gases, suggesting that wealthier nations have a responsibility to help China build environmental protection into its growth.

Clearing the Air is written for diverse readers, providing a bridge from underlying research to policy implications, with easily accessible overviews of issues and summaries of the findings for nonspecialists and policymakers followed by more specialized, interlinked studies of primary interest to scholars. Taken together, these analyses offer a uniquely integrated assessment that supports the book's economic and policy recommendations.

2006
Xiaoqi Guo. 2006. “The economic value of air-pollution-related health risks in China.” Department of Agricultural, Environmental and Development Economics, Ohio State University.
James K Hammitt and Ying Zhou. 2006. “The economic value of air-pollution-related health risks in China: A contingent valuation study.” Environmental Resource Economics, 33, 3, Pp. 399-423. Publisher's VersionAbstract
The economic value of preventing adverse health effects related to air pollution is estimated using contingent valuation in three diverse locations in China. Values are estimated for three health endpoints: cold, chronic bronchitis, and fatality. Alternative statistical models are tested to study their impact on estimated willingness to pay (WTP) and on the relationship between WTP and respondent characteristics. Using the official exchange rate, the sample-average median WTP to prevent an episode of cold ranges between US$3 and US$6, the WTP to prevent a statistical case of chronic bronchitis ranges between US$500 and US$1,000, and the value per statistical life ranges between US$4,000 and US$17,000. Estimated mean values are between two and thirteen times larger. Our estimates are between about 10 and 1,000 times smaller than estimates for the US and Taiwan using official exchange rates. Indoor air quality, measured for a subset of respondents, shows no consistent relationship with WTP.
Ying Zhou, Jonathan I Levy, John S Evans, and James K Hammitt. 2006. “The influence of geographic location on population exposure to emissions from power plants throughout China.” Environment International, 32, 3, Pp. 365-373. Publisher's VersionAbstract
This analysis seeks to evaluate the influence of emission source location on population exposure in China to fine particles and sulfur dioxide. We use the concept of intake fraction, defined as the fraction of material or its precursor released from a source that is eventually inhaled or ingested by a population. We select 29 power-plant sites throughout China and estimate annual average intake fractions at each site, using identical source characteristics to isolate the influence of geographic location. In addition, we develop regression models to interpret the intake fraction values and allow for extrapolation to other sites. To model the concentration increase due to emissions from selected power plants, we used a detailed long-range atmospheric dispersion model, CALPUFF. Primary fine particles have the highest average intake fraction (1 × 10− 5), followed by sulfur dioxide (5 × 10− 6), sulfate from sulfur dioxide (4 × 10− 6), and nitrate from nitrogen oxides (4 × 10− 6). For all pollutants, the intake fractions span approximately an order of magnitude across sites. In the regression analysis, the independent variables are meteorological proxies (such as climate region and precipitation) and population at various distances from the source. We find that population terms can explain a substantial percentage of variability in the intake fraction for all pollutants (R2 between 0.86 and 0.95 across pollutants), with a significant modifying influence of meteorological regime. Near-source population is more important for primary coarse particles while population at medium to long distance is more important for primary fine particles and secondary particles. A significant portion of intake fraction (especially for secondary particles and primary fine particles) occurs beyond 500 km of the source, emphasizing the need for detailed long-range dispersion modeling. These findings demonstrate that intake fractions for power plants in China can be estimated with reasonable precision and summarized using simple regression models. The results should be useful for informing future decisions about power-plant locations and controls.
Shuxiao Wang, Jiming Hao, Mun S Ho, Ji Li, and Yongqi Lu. 2006. “Intake fractions of industrial air pollutants in China: Estimation and application.” Science of the Total Environment, 354, Pp. 127-141. Publisher's VersionAbstract
Intake fractions, an emissions-intake relationship for primary pollutants, are defined and are estimated in order to make simple estimates of health damages from air pollution. The sulfur dioxide (SO2) and total suspended particles (TSP) intake fractions for five cities of China are estimated for the four main polluting industries—electric power generation, mineral (mostly cement) products industry, chemical process industry and metallurgical industry (mainly iron and steel smelting). The Industrial Source Complex Long Term (ISTLT3) model is used to simulate the spatial distribution of incremental ambient concentrations due to emissions from a large sample of site-specific sources. Detailed population distribution information is used for each city. The average intake fractions within 50 km of these sources are 4.4 × 10- 6 for TSP, and 4.2 × 10- 6 for SO2, with standard deviations of 8.15 × 10- 6 and 9.16 × 10- 6, respectively. They vary over a wide range, from 10- 7 to 10- 5. Although the electric power generation has been the focus of much of the air pollution research in China, our results show that it has the lowest average intake fraction for a local range among the four industries, which highlights the importance of pollutant emissions from other industrial sources. Sensitivity analyses show how the intake fractions are affected by the source and pollutant characteristics, the most important parameter being the size of the domain. However, the intake fraction estimates are robust enough to be useful for evaluating the local impacts on human health of primary SO2 and TSP emissions. An application of intake fractions is given to demonstrate how this approach provides a rapid population risk estimate if the dose-response function is linear without threshold, and hence can help in prioritizing pollution control efforts.
Hong Wang and John Mullahy. 2006. “Willingness to pay for reducing fatal risk by improving air quality: A contingent valuation study in Chongqing, China.” Science of the Total Environment, 367, Pp. 50-57. Publisher's VersionAbstract

In China, 76% of all energy comes from coal consumption, which is the major cause of air pollution. One of the major barriers to developing sound policies for controlling air pollution is the lack of information related to the value of the health consequences of air pollution. We conducted a willingness-to-pay (WTP) study using contingent valuation (CV) methods in Chongqing, China to estimate the economic value of saving one statistical life through improving air quality.

A sample of 500 residents was chosen based on multistage sampling methods. A face-to-face household interview was conducted using a series of hypothetical, open-ended scenarios followed by bidding game questions designed to elicit the respondents' WTP for air pollution reduction. The Two-Part Model was used for estimations.

The results show that 96% of respondents were able to express their WTP. Their mean annual income is $490. Their WTP to save one statistical life is$34,458. Marginal increases for saving one statistical life is $240 with 1 year age increase,$14,434 with 100 yuan monthly income increase, and \$1590 with 1 year education increase. Unlike developed country, clean air may still be considered as a “luxury” good in China based on the estimation of income elasticity.

2003
Y. Zhou, Jonathan I Levy, James K Hammitt, and John S Evans. 2003. “Estimating population exposure to power plant emissions using CALPUFF: A case study in Beijing, China.” Atmospheric Environment, 37, 6, Pp. 815-826. Publisher's VersionAbstract
Epidemiological studies have shown a significant association between ambient particulate matter (PM) exposures and increased mortality and morbidity risk. Power plants are significant emitters of precursor gases of fine particulate matter. To evaluate the public health risk posed by power plants, it is necessary to evaluate population exposure to different pollutants. The concept of intake fraction (the fraction of a pollutant emitted that is eventually inhaled or ingested by a population) has been proposed to provide a simple summary measure of the relationship between emissions and exposure. Currently available intake fraction estimates from developing countries used models that look only at the near field impacts, which may not capture the full impact of a pollution source. This case study demonstrated how the intake fraction of power plant emissions in China can be calculated using a detailed long-range atmospheric dispersion model—CALPUFF. We found that the intake fraction of primary fine particles is roughly on the order of 10−5, while the intake fractions of sulfur dioxide, sulfate and nitrate are on the order of 10−6. These estimates are an order of magnitude higher than the US estimates. We also tested how sensitive the results were to key assumptions within the model. The size distribution of primary particles has a large impact on the intake fraction for primary particles while the background ammonia concentration is an important factor influencing the intake fraction of nitrate. The background ozone concentration has a moderate impact on the intake fraction of sulfate and nitrate. Our analysis shows that this approach is applicable to a developing country and it provides reasonable population exposure estimates.
Scott A. Venners, B.Y. Wang, Z.G. Peng, Y. Xu, L.H. Wang, and X.P. Xu. 2003. “Particulate matter, sulfur dioxide, and daily mortality in Chongqing, China.” Environmental Health Perspectives, 111, 4, Pp. 562-567. Publisher's VersionAbstract
In 1995, daily mortality in a district of Chongqing, China, was analyzed from January through
December for associations with daily ambient sulfur dioxide and fine particles (airborne particles
with diameters ≤ 2.5 μm; PM2.5). The mean concentration of PM2.5 was 147 μg/m3 (maximum,
666 μg/m3), and that of SO2 was 213 μg/m3 (maximum, 571 μg/m3). On average, 9.6 persons
died each day. We used a generalized additive model using robust Poisson regression to estimate
the associations of mean daily SO2 and PM2.5 with daily mortality (on the same day and at lags up
to 5 days) adjusted for trend, season, temperature, humidity, and day of the week. The relative
risk of mortality associated with a 100 μg/m3 increase in mean daily SO2 was highest on the second
lag day [1.04; 95% confidence interval (CI), 1.00–1.09] and the third lag day (1.04; 95% CI,
0.99–1.08). The associations between daily mortality and mean daily PM2.5 were negative and statistically
insignificant on all days. The relative risk of respiratory mortality on the second day after
a 100 μg/m3 increase in mean daily SO2 was 1.11 (95% CI, 1.02–1.22), and that for cardiovascular
mortality was 1.10 (95% CI, 1.02–1.20). The relative risk of cardiovascular mortality on the
third day after a 100 μg/m3 increase in mean daily SO2 was 1.20 (95% CI, 1.11–1.30). The relative
risks of mortality due to cancer and other causes were insignificant on both days. The estimated
effects of mean daily SO2 on cardiovascular and respiratory mortality risk remained after controlling for PM2.5.
2002
Ying Zhou. 2002. “Evaluating Power Plant Emissions in China: Human Exposure and Valuation.” Harvard School of Public Health.
Mun S Ho, Dale W Jorgenson, and Wenhua Di. 2002. “Pollution taxes and public health.” In Economics of the Environment in China, edited by Jeremy J. Warford and Yi Ning Li. Bethesda, MD: Aileen International Press.
Jonathan I Levy, Scott K. Wolff, and John S Evans. 2002. “A regression-based approach for estimating primary and secondary particulate matter intake fractions.” Risk Analysis, 22, 5, Pp. 893-901. Publisher's VersionAbstract
One of the common challenges for life cycle impact assessment and risk assessment is the need to estimate the population exposures associated with emissions. The concept of intake fraction (a unitless term representing the fraction of material or its precursor released from a source that is eventually inhaled or ingested) can be used when limited site data are available or the number of sources to model is large. Although studies have estimated intake fractions for some pollutant‐source combinations, there is a need to quickly and accurately estimate intake fractions for sources and settings not previously evaluated. It would be expected that limited source or site information could be used to yield intake fraction estimates with reasonable accuracy. To test this theory, we developed regression models to predict intake fractions previously estimated for primary fine particles (PM2.5) and secondary sulfate and nitrate particles from power plants and mobile sources in the United States. Our regression models were able to predict pollutant‐specific intake fractions with R2 between 0.53 and 0.86 and equations that reflected expected relationships (e.g., intake fraction increased with population density, stack height influenced the intake fraction of primary but not secondary particles). Further analysis would be needed to generalize beyond this case study and construct models applicable across source categories and settings, but our analysis demonstrates that inclusion of a limited number of parameters can significantly reduce the uncertainty in population‐average exposure estimates.
2001
Scott A. Venners, Binyan Wang, Jiatong Ni, Yongtang Jin, Jianhua Yang, Zhian Fang, and Xiping Xu. 2001. “Indoor air pollution and respiratory health in urban and rural China.” International Journal of Occupational and Environmental Health , 7, 3, Pp. 173-181. Publisher's VersionAbstract
During the summer of 1999, information about respiratory health outcomes and relevant covariates was collected from 3,709 Chinese adults in Beijing, Anqing City, and rural communities in Anqing Prefecture. Indoor PM10 and SO2 were measured in a random sample of selected households. Using logistic regression and controlling for important covariates (excluding PM10 and SO2) and familial intraclass correlation, highly significant differences were found between study areas in the prevalences of chronic cough, chronic phlegm, wheeze, and shortness of breath, but not physician-diagnosed asthma. Generally, the lowest prevalence of respiratory symptoms was observed in Anqing City, a higher prevalence in rural Anqing, and the highest prevalence in Beijing. Median indoor concentrations of PM10 were similar in Anqing City (239 microg/m3) and rural Anqing (248 microg/m3), but much higher in Beijing (557 microg/m3). Median indoor concentrations of SO2 were similar in all three areas (Beijing: 14 microg/m3, Anqing City: 25 microg/m3, rural Anqing: 20 microg/m3).
2000
Z.Y. Xu, D.Q. Yu, L.B. Jing, and X.P. Xu. 2000. “Air pollution and daily mortality in Shenyang, China.” Archives of Environmental Health, 55, 2, Pp. 115-120. Publisher's VersionAbstract
The authors analyzed daily mortality data in Shenyang, China, for calendar year 1992 to identify possible associations with ambient sulfur dioxide and total suspended particulates. Both total suspended particulate concentrations (mean = 430 μmlg/m3, maximum = 1,141 μmlg/m3) and sulfur dioxide concentrations (mean 197 = μmlg/m3, maximum = 659 μmlg/m3) far exceeded the World Health Organization's recommended criteria. An average of 45.5 persons died each day. The lagged moving averages of air-pollution levels, calculated as the mean of the nonmissing air-pollution levels of the concurrent and 3 preceding days, were used for all analyses. Locally weighted regression analysis, including temperature, humidity, day of week, and a time variable, showed a positive association between daily mortality and both total suspended particulates and sulfur dioxide. When the authors included total suspended particulates and sulfur dioxide separately in the model, both were highly significant predictors of daily mortality. The risk of all-cause mortality increased by an estimated 1.7% and 2.4% with a 100-μmlg/m3 concomitant increase in total suspended particulate and sulfur dioxide, respectively. When the authors analyzed mortality separately by cause of death, the association with total suspended particulates was significant for cardiovascular disease (2.1%), but not statistically significant for chronic obstructive pulmonary diseases (2.6%). In contrast, the association with sulfur dioxide was significant for chronic obstructive pulmonary diseases (7.4%), but not for cardiovascular disease (1.8%). The mortality from cancer was not associated significantly with total suspended particles or with sulfur dioxide. The correlation between sulfur dioxide and total suspended particulates was high (correlation coefficient = .66). When the authors included sulfur dioxide and total suspended particulates simultaneously in the model, the association between total suspended particulates and mortality from all causes and cardiovascular diseases remained significant. Sulfur dioxide was associated significantly with increased mortality from chronic obstructive pulmonary diseases and other causes. The results of the current study reveal increased mortality associated with both total suspended particulates and sulfur dioxide.
1999
B.Y. Wang, Z.G. Peng, X.B. Zhang, Y. Xu, H.J. Wang, G. Allen, L.H. Wang, and X.P. Xu. 1999. “Particulate matter, sulfur dioxide, and pulmonary function in never-smoking adults in Chongqing, China.” International Journal of Occupational and Environmental Health , 5, 1, Pp. 14-19. Publisher's VersionAbstract
Chongquing is one of the most polluted cities in China. To study the respiratory health effects of air pollution for this city, the authors monitored the ambient levels of particulate matter (PM2.5) and sulfur dioxide (SO2) in urban and suburban areas and performed pulmonary function testing on 1,075 adults 35 to 60 years of age who had never smoked and did not use coal stoves for cooking or heating. The mean concentration of SO2 in the urban areas (213 micrograms/m3) was twice as high as that in suburban areas (103 micrograms/m3). Mean PM2.5 levels were high in both urban (143 micrograms/m3) and suburban (139 micrograms/m3) areas. A generalized additive model was used to estimate the differences between the two areas in FEV1, FVC, and FEV1/FVC%, with adjustment for potential confounding factors, including sex, age, height, education, passive smoking, and occupational exposures to dust, gas, or fumes. Estimated differences in FEV1 between the urban and suburban areas were 199 mL (SE = 50 mL) for men and 87 mL (SE = 30 mL) for women, both statistically significant. When the men and women were pooled, the estimated difference in FEV1 was 126 mL (SE = 27 mL). Similar trends were observed for FVC and FEV1/FVC%. After exclusion of 104 subjects with histories of occupational exposures to dust, gas, or fumes, the estimated difference was some-what smaller than that of the total samples. However, the effects on FEV1 and FEV1/FVC% remained significant for both men and women.
1998
X.P. Xu. 1998. “Air pollution and its health effects in urban China.” In Energizing China: Reconciling Environmental Protection and Economic Growth, edited by M.B. McElroy, C.P. Nielsen, P. Lydon, and eds.. Cambridge, MA: HUCE/Harvard University Press. Publisher's VersionAbstract

As China develops its booming, fossil fuel-powered economy, is it taking lessons from the history of Western industrialization and the unforeseen environmental harms that accompanied it? Given the risks of climate change, is there an imperative, shared responsibility to help China respond to the environmental effects of its coal dependence? By linking global hazards to local air pollution concerns—from indoor stove smoke to burgeoning ground-level ozone—this volume of eighteen studies seeks integrated strategies to address simultaneously a range of harmful emissions. Counterbalancing the scientific inquiry are key chapters on China’s unique legal, institutional, political, and cultural factors in effective pollution control.

Energizing China, the stage-setting publication of an ongoing program of Harvard–China research collaboration, is distinguished by its conceptual breadth and spirit of exchange. Its contributors include twenty-two Western and seventeen Chinese scholars with a disciplinary reach that includes science, public health, engineering, economics, public policy, law, business, and China studies.

1998. Energizing China: Reconciling Environmental Protection and Economic Growth. Cambridge, MA: HUCE/Harvard University Press. Publisher's VersionAbstract

As China develops its booming, fossil fuel-powered economy, is it taking lessons from the history of Western industrialization and the unforeseen environmental harms that accompanied it? Given the risks of climate change, is there an imperative, shared responsibility to help China respond to the environmental effects of its coal dependence? By linking global hazards to local air pollution concerns—from indoor stove smoke to burgeoning ground-level ozone—this volume of eighteen studies seeks integrated strategies to address simultaneously a range of harmful emissions. Counterbalancing the scientific inquiry are key chapters on China’s unique legal, institutional, political, and cultural factors in effective pollution control.

Energizing China, the stage-setting publication of an ongoing program of Harvard–China research collaboration, is distinguished by its conceptual breadth and spirit of exchange. Its contributors include twenty-two Western and seventeen Chinese scholars with a disciplinary reach that includes science, public health, engineering, economics, public policy, law, business, and China studies.

R.C. Peng, L.H. Wang, H. Wang, K.B. He, and X.P. Xu. 1998. “Indoor air pollution from residential energy use in China.” In Energizing China: Reconciling Environmental Protection and Economic Growth, edited by M.B. McElroy, C.P. Nielsen, P. Lydon, and eds.. Cambridge, MA: HUCE/Harvard University Press. Publisher's VersionAbstract

As China develops its booming, fossil fuel-powered economy, is it taking lessons from the history of Western industrialization and the unforeseen environmental harms that accompanied it? Given the risks of climate change, is there an imperative, shared responsibility to help China respond to the environmental effects of its coal dependence? By linking global hazards to local air pollution concerns—from indoor stove smoke to burgeoning ground-level ozone—this volume of eighteen studies seeks integrated strategies to address simultaneously a range of harmful emissions. Counterbalancing the scientific inquiry are key chapters on China’s unique legal, institutional, political, and cultural factors in effective pollution control.

Energizing China, the stage-setting publication of an ongoing program of Harvard–China research collaboration, is distinguished by its conceptual breadth and spirit of exchange. Its contributors include twenty-two Western and seventeen Chinese scholars with a disciplinary reach that includes science, public health, engineering, economics, public policy, law, business, and China studies.