1、The Effect of Air Pollution on Human Health in China: A Macro Evaluation Zhigang Chen, Xianjin Huang School of Geographic human health; effect evaluation; health production function; China I. INTRODUCTION It is well known that the harm of air pollution to human health is relatively serious and direc
2、t. Its ever estimated by World Health Organization (WHO) that there are 2.7 million people died of air pollution around the world every year 1. Also its indicated by the research of American Cancer Association that with the rising of each 10g/m3fine Particulates in air, the fatalness of total mortal
3、ity, corpulmonale mortality and lung cancer mortality will be increased by 4%, 6% and 8% respectively 2. At present, China is at the rapid advancement stage of industrialization and urbanization, a large amount of air pollutants discharged by industrial production and residents living including dust
4、, sulfur dioxide and nitrogen oxides, etc. will inevitably do harm to human health. In order to explore the effect of air pollution on human health in China, the scholars have developed further and systematical research. From the existing literatures, the researches on the effect of air pollution on
5、 human health in China are mainly epidemiological studies and risk evaluation based on investigation data 3. It is very helpful to grasp the relationship between related diseases and air pollution, but goes against the overall control of the effect of air pollution on human heath of environmental ma
6、nagement departments. This paper is trying to build a health production function based on related macro statistical data to evaluate the effect of air pollution on human health in China to provide decision basis for the improvement of related environmental control policies. II. AIR POLLUTION AND HUM
7、AN HEALTH: GENERAL DESCRIPTION Air is one of the important environmental factors for living beings to live, which is directly involved in the living activities of human including metabolism and thermoregulation, etc Consequently, once the air is polluted, human health will certainly be seriously inf
8、luenced. The effect of air pollution on human health is manifested in many aspects: The first is the harm of inhalable particulates to human health. Inhalable particulates can be inhaled into bronchus and lung by breathing and cause sediment hence induce lung disease and cardiovascular disease, etc.
9、; these fine particulates are also carriers of poisonous and harmful elements like bacteria, virus, heavy metal and organic compounds, etc., and can cause carcinogenesis and cancer-promoting. The second is the harm of sulfur dioxide to human health. Sulfur dioxide takes part in oxidation reaction in
10、 the atmosphere and generates acid mist, which has acute stimulation to eye conjunctiva, nasal cavity and respiratory tract mucosa of people and cause pulmonary inflammation and pulmonary edema in severe case 4. The third is the harm of nitrogen oxide to human health. Under general conditions, when
11、the pollutant is mainly of nitrogen dioxide, the harm to lung will be more apparent, and may cause lesions mainly of pulmonary edema in severe case. While in case there is a large amount of nitric oxide in mixed gas, methemoglobinemia and central nervous system involvement will appear. The forth is
12、the harm of hydrogen sulfide gas and carbon monoxide to human health. Hydrogen sulfide gas has influence on respiratory system, circulatory system, digestive system, endocrine system and nervous system; and carbon monoxide is one kind of toxicant which is harmful to blood and nerve. The fifth is the
13、 harm of photochemical smog to human health. Photochemical smog is mainly formed by the photochemical reaction of nitrogen oxide and hydrocarbon of automobile exhausts under the action of intense sunlight, which will make the eyes, throat and This work was sponsored by the industry research project
14、for publicwelfare of the MLR of China (200811033) and the talent cultivation project of the MOE of China (NCET-05-0451). Corresponding author: Xianjin Huang 978-1-4244-2902-8/09/$25.00 2009 IEEE1extremities of the victim feel unwell and even cause consciousness disturbance in severe case 5. From the
15、 research of related fields, at present, some scholars have developed further epidemiological studies on air pollution in major cities of China including Beijing, Shanghai, Guangzhou, Shenyang and so on. These studies approve that air pollution has close relation with the increase of morbidity and m
16、ortality of respiratory system diseases and circulatory system diseases 6. III. EVALUATION OF EFFECTS OF AIR POLLUTION ON HUMAN HEALTH The above general description of the relationship between air pollution and human health is only the brief analysis based on related research achievements of epidemi
17、ology. However, in order to make a general evaluation of health effect of air pollution from national (or regional) level, it is necessary to carry out concretely by means of macro evaluation model. A. Evaluation Model: Health Production Function According to modern medical theory, human health depe
18、nds on various factors including environmental factor, living style and behavior factor, biological inheritance factor, medical and hygiene service factor and so on 7. Therefore, in order to evaluate the effect of air pollution on human health from macro level, it is obvious that other factors shall
19、 not be neglected. For this, the health production function proposed by Grossman based on health demand model provides an ideal model foundation to us. Grossman considers health as a kind of commodity, and people invest for self health (including purchasing commodities related with health, paying hy
20、giene on the 2other hand, it can also avoid the neglect of regional development characteristics while just using time series data for estimation. C. Estimated Results Based on above data, we select three periods for model estimation, respectively 20012007, 20012004 and 20042007. Therefore, we can no
21、t only master the overall effect of air pollution on human health from 2001 to 2007, but also primarily understand the changes of health effects of air pollution during this period. On the selection of model estimation method, firstly, we estimate the model by applying ordinary least squares (OLS).
22、Then, considering that the data selected here are panel data, we also adopt generalized least squares (GLS) in addition to OLS for model estimation. Table and table list the OLS and GLS results of model estimation respectively. TABLE I. THE OLS RESULTS OF MODEL ESTIMATION Variables Estimated Coeffic
23、ients 20012007 20012004 20042007 C 2.050* (18.811) 2.001* (13.310) 1.921* (10.520) ln pg 0.027* (2.192) 0.022 (1.270) 0.011 (0.551) ln ph 0.099* (3.579) 0.079* (2.294) 0.149* (3.429) ln pa 0.009* (1.922) 0.009 (1.388) 0.008 (1.309) Adj. R20.170 0.121 0.191 F-statistic 15.728 6.632 10.653 Note: the v
24、alue in the brackets is the t value of the corresponding coefficient; *, * and * respectively means that the significant level of the statistical test is 10%, 5% and 1%. TABLE II. THE GLS RESULTS OF MODEL ESTIMATION Variables Estimated Coefficients 20012007 20012004 20042007 C 2.062* (35.100) 1.936*
25、 (25.836) 2.017* (18.711) ln pg 0.031 (5.039) 0.017* (2.117) 0.026* (2.155) ln ph 0.092* (8.360) 0.085* (7.845) 0.127* (6.191) ln pa 0.015* (5.279) 0.013* (3.798) 0.016* (5.372) Adjusted R20.998 0.999 0.998 F-statistic 43357 51789 26906 Note: the value in the brackets is the t value of the correspon
26、ding coefficient; *, * and * respectively means that the significant level of the statistical test is 10%, 5% and 1%. Judging from the overall results of model estimation, the estimated results of GLS are much better than those of OLS, for the former not only greatly improve the goodness of fit (Adj
27、usted R2) of model estimation, but also improve the significance level of most of estimated coefficients. The main reason why the estimated results of GLS are better than those of OLS is that GLS estimation can reduce the bias caused by multicollinearity and heteroscedasticity that may exist simulta
28、neously in panel data. Therefore, here we shall analyze the concrete effect of air pollution on human health from the following two aspects, according to GLS estimation results. On one hand, per capita GDP, the index reflecting economy & living conditions and number of doctors per thousand people, t
29、he index reflecting hygiene & medical conditions, have significant positive effect on human health. According to the corresponding elastic coefficients, we can see that from 2001 to 2007, with the rising of each 1% per capita GDP or number of doctors per thousand people, the human mortality will be
30、decreased by 0.03% and 0.09% respectively. Taking 2004 as the watershed, the positive effect of economy & living conditions and hygiene & medical conditions on human health during 20042007 is obviously better than that during 20012004. It is obvious that the positive effect of economic development a
31、nd improvement of hygiene & medical conditions on human health in China is expanding. On the other hand, the index reflecting air pollution degree has obvious negative effect on human health. According to the corresponding elastic coefficient, we can see that from 2001 to 2007, with the rising of ea
32、ch 1% air pollution degree, the human mortality will be increased by 0.015%. Also taking 2004 as the watershed, we can conclude that the negative effect of air pollution on human health shall tend to reinforcement. In Table 1, we can see that the influencing elasticity (0.016) of air pollution on mo
33、rtality during 20042007 is obviously higher than that of 20012004 (0.013). It is obvious that the negative effect of air pollution on human health in China is expanding. Therefore, in order to improve the health level of Chinese population, we must strictly control air pollution and expedite the pol
34、lution treatment. IV. CONCLUSIONS Based on the general description of the relationship between air pollution and human health, this paper has brought factors of air pollution into health production function model and evaluated the effect of air pollution on human health in China by applying related
35、macro statistical data. The results show that, from 2001 to 2007, with the rising of each 1% air pollution degree in China, the human mortality will be increased by nearly 0.015%. While from the influence variation of air pollution on human health around 2004, we can see that the influencing elastic
36、ity of air pollution on human mortality after 2004 is increased by 23% than that before 2004. Of course, the results of positive analysis also reveal that the improvement of both economic & living conditions and hygiene & medical conditions would promote the health conditions of population in China.
37、 Therefore, in order to improve the human health conditions in China, on one hand, related environmental control policies must be optimized, especially the strict control of discharge of air pollutants and harnessing strength of air pollution. On the other hand, it is also one of the important measu
38、res to improve the health conditions 3of population in China that promote sustainable economic development and improve hygiene & medical conditions. REFERENCES 1 WHO, “WHO Guidelines for air quality,” Fact sheet No. 187. 2003. 2 C. G. Cai, X. Y. Zheng, “The payment of the human health loss caused by
39、 air pollution in Beijing,” Economic Science, 2007, No. 1, pp. 107-115. 3 Committee of Environment, Chinese Academy of Engineering, “The effect of environment pollution on human health: the proceedings of international workshop of environment pollution and human health,” Beijing: China Environmental
40、 Science Press, 2005. 4 F. Z. Chao, “Reports for environment and human health in China,” Beijing: China Environmental Science Press, 1999. 5 G. Z. Zhang, R. Chu, Z. R. Zhong, “Influence of air pollution on the health and economic loss in Lanzhou,” Journal of Arid Land Resources and Environment, 2008
41、, vol. 22, No. 8, pp. 120-123. 6 M. X. Han, X. M. Guo, “Effect of air pollution on residents health in Chinas cities,” City Planning Review, 2006, vol. 30, No. 6, pp. 84-87. 7 M. A. Lalonde, “New perspective on the health of Canadians,” Ottawa: Health and Welfare, 1974. 8 M. Grossman, “On the concep
42、t of health capital and the demand for health,” Journal of Political Economy, 1972, vol. 80, pp. 223-255. 9 A. T. Flegg, “Inequality of income, illiteracy and medical care as determinants of infant mortality in underdeveloped countries,” Population Studies, 1982, vol. 36, pp. 441-458. 10 L. Pritchet
43、t, L. Summers, “Wealthier is healthier,” Journal of Human Resources, 1996, vol. 31, pp. 841-868. 11 Y. Q. Miao, “Effects of air pollution on health in Linfen city: method of health production function,” China Population, Resources and Environment, 2008, vol. 18, No. 5, pp. 205-209. 12 J. Wang, Z. Z. Chang, “China macro health production function: theory and positive analysis,” Nankai Economic Studies, 2007, No. 2, pp. 20-42. 4
