Berkeley Earth released a study showing that air pollution kills an average of 4000 people every day in China, 17% of all China’s deaths. For 38% of the population, the average air they breathe is “unhealthy” by U.S. standards. With unprecedented detail, the sources of pollution throughout China are mapped directly from ground-level measurement.
The most harmful pollution is PM2.5, particulate matter 2.5 microns and smaller. This penetrates deeply into lungs and triggers heart attacks, stroke, lung cancer, and asthma. “Beijing is only a moderate source PM 2.5; it receives much of its pollution from distant industrial areas, particularly Shijiazhuang, 200 miles to the southwest,” says Robert Rohde, coauthor of the paper. Since the sources aren’t local, reducing pollution for the 2022 Olympics may prove difficult
Why does air pollution kill so many people it is like forcing everyone in the air polluted area in China to smoke 1.5 cigarettes every hour. This forced smoking includes babies (including premature births), elderly people, and people with lung disease or asthma.
The paper has been accepted for publication in the refereed journal PLOS ONE. Berkeley Earth analyzed hourly measurements of 1500 ground stations covering 4 months. The fact that sources of PM2.5 match those of sulfur implies that most of the pollution comes from coal. Worldwide, [outdoor] air pollution kills over three million people per year–more than AIDS, malaria, diabetes or tuberculosis
During the period analyzed, 92% of the population of China experienced >120 hours of unhealthy air (as defined by the US EPA standard), and 38% experienced average concentrations that were unhealthy. China’s population-weighted average exposure to PM2.5 was 52 μg/m3.
The calculated mortality is somewhat higher than the 1.2 million deaths/year previously estimated from a Huai River study using Chinese air pollution measurements and mortality data.