时间: 2018年10月12日（周五）14：00 – 15：30
研究简介： In the past three decades, China has experienced a historically unprecedented economic growth. However, this economic miracle does not come without any expense, one of which is the severe environmental crisis in the form of water pollution and, in particular, ambient air pollution. Nowadays, air quality is notoriously poor and has become a big public concern in China.
There is probably no disagreement that air pollution poses risks on human health. It has been well documented that air pollution is closely associated with many diseases, such as the cardiovascular disease, respiratory disease and so on, and then it in turn increases the cardiorespiratory mortality and decreases the life expectancy. However, studies that adopting quasi-experimental approach to estimate the causal effect of the air pollution on health are relatively limited and the majority of them overwhelmingly focus on developed countries. So far, only a very limited evidence on the causal effect of the air pollution on health in China. And as far as we know, so far there is no research estimating the causal effect of the long-term exposure of PM2.5 on the Chinese elderly health and the pollution-sensitive diseases.
This paper attempts to fill the gap mentioned above. Using PM2.5 data computed from NASA satellite data and 2011 wave of Chinese Longitudinal Healthy Longevity Survey, this paper estimates the causal effects of air pollution on elderly health and multiple chronic diseases. We adopt an instrumental variable constructed using the wind speed for the indicator of air pollution, PM2.5 mass concentration level. Consistent with most existing research, it finds that the elevation of air pollution is detrimental to elderly health and increases the risk of cardiovascular and respiratory diseases. Specifically, an increase of 10 μg/m3 in the PM2.5 mass concentration will lead to an increase of 6, 12, and 4 percentage points in ADL impaired, cardiovascular and respiratory diseases, respectively.
We conduct a set of robustness checks and a placebo test, and our results survive, which shows our results are robust and credible. Meanwhile, our heterogeneity analysis shows that the adverse health impact does not distributed evenly across different groups. Generally speaking, the female, rural, uneducated, and poor elders suffered more health loss from the air pollution.
We further try to monetize the health impact by estimating the medical expenditure due to the cardiovascular and respiratory disease related to air pollution. Our estimate shows, an increase of 10 μg/m3 in PM2.5, the marginal increase of national medical expenditure due to cardiovascular and respiratory disease will exceed 80 billion RMB for the elders.
This paper is the first attempt to estimate the causal effect of the long-term exposure of PM2.5 on the elderly health and related diseases amidst Chinese elderly. It helps to quantitate the public health benefits of improving air quality and hence provide the policy makers with evidence to better balance the trade-off between the related economic costs and public health benefits when making environment regulations.