A China air pollution study that was sensationalized in the Western press and local expat media in 2017 has since been updated.
The original study caused quite a stir in the expat community as it indicated living in China could take years off your life. Here we will take a deeper look at this series of studies conducted by the Energy Policy Institute of Chicago University (EPIC) that now paint a more sanguine picture of China's battle with air pollution.
Does living in Shanghai really take six years off your life due to air pollution?
Reports with headlines such as ‘Living in China Takes 3½ Years Off Your Life’ and ’Living in Shanghai Takes Nearly 6 Years Off Your Life’ were shared extensively by the expat community on social media in 2017.
These articles were based on a China air pollution study released by the University of Chicago’s Energy Policy Institute; “The Impact of Sustained Exposure to Particulate Matter on Life Expectancy: New Evidence from China’s Huai River Policy”.
The researchers used an in-depth analysis of mortality data to show the connection between China’s policy of installing coal-powered residential heating systems in Chinese cities North of the Huai River since the 1950’s and an increase in cardiorespiratory related deaths in those areas due to the increased particulate matter (PM) emitted. This study was a follow up to an earlier study which analyzed the same phenomenon.
The Huai river is located between China’s Northern Yellow River and Central Yangtze River and traditionally is considered the demarcation line between North and South China.
Based on an analysis of the statistics the researchers calculated that life expectancy for residents North of the Huai River was on average 3.1 years less than for residents living to the South of the River where no such coal-powered heating infrastructure was installed.
The researchers further used their data to come up with a metric showing the impact of increased PM2.5 exposure on life expectancy. They estimate that for every extra 10 μg/m3 of average PM2.5 life-time exposure 1.03 life-years are lost.
Based on this metric the same institute has developed an Air Quality-Life Index™ to estimate how average life expectancy around the world is impacted by local air pollution. The ALQI website (under the Data and Methodology tab) explains how they made their calculations.
The Western and local expat media seized on this metric to create their sensational headlines.
The fact that air pollution has serious effects on our health is not in contention, and this China air pollution study does provide valuable evidence of the serious health impact from coal-burning emissions.
A different interpretation of the same study, however, can show us how efforts since 2013 to reduce air pollution in China are increasing life expectancy.
The average annual PM2.5 density in Shanghai dropped from 62 ug/m3 in 2013 to 45 in 2016 and in Beijing from 89.5 to 73 in the same time span.
By applying the UofC AQLI metric, therefore, we can come up with a much more sanguine interpretation; the decrease in PM2.5 air pollution between 2013 and 2016 has increased life expectancy in both Shanghai and Beijing by about 1.7 years.
Even when compared to a PM2.5 density of 0; a very unlikely level for most major cities, Shanghai’s 2016 average PM2.5 density of 45 would only result in a hit on life-expectancy of less than 5 years to long-term residents.
Considering that average PM2.5 pollution in most large North American and European cities is between 15 and 20 ug/m3, the hit on life expectancy for long-term residents in Shanghai directly related to air pollution was less than 3 years in 2016 when compared to living in most Western cities; and even lower today as Shanghai's air quality continues to improve.
Another conclusion of the University of Chicago's China air pollution study was that the Huai River Policy "...had disastrous consequences for human health".
Analyzing the real-world situation, however, does not support this argument.
Due to the colder weather to the North of the Huai River more winter heating is essential for a livable environment.
The central heating systems use coal-fired boilers to heat water which is pumped to radiators in residences. These boilers do cause heavy emissions, but we should compare this drawback to the alternatives available.
Clean and green energy were not economically viable until recently. The more likely alternative, therefore, was coal or wood stoves inside residences which would likely create just as much outdoor air pollution and certainly more indoor air pollution.
After making a comeback in the UK in recent years, experts have warned that residential wood burning stoves are also disastrous to our health. The Mayor of London has launched a campaign to ban the practice to tackle air pollution.
In 2017 China began to invest heavily to switch from coal-fired heating systems to natural gas and other cleaner energies.
This switch to cleaner sources of energy for heating originally led to some unanticipated consequences. People in some cities in North China which had installed new gas lines and shut down coal-fired boilers were left in the cold, literally, when gas ran out. Old coal-fired boilers have had to be turned back on.
Concluding that such essential heating systems were 'disastrous', therefore, is not accurate.
In an online report by the University of Chicago to announce the launch of the China air pollution study it was also acknowledged that "Since the earlier paper, China has increased its efforts to confront its air pollution challenge. China is switching its primary source of heating from coal-fired boilers to gas-fired or electric units, and it has shut down many polluting plants. The consequence is that particulate air pollution in some of China’s most polluted cities, such as Beijing, has improved significantly."
In 2018 EPIC released another follow-up to its China air pollution study.
Acknowledging the great success of China's first air pollution action plan covering the years 2013 to 2017 which brought significant decreases in average PM2.5 concentrations in China, the institute noted that based on its AQLI metric Chinese residents life expectancy was on average 2.4 years longer at the end of 2017 than when the plan was launched in 2013.
Beijing residents saw an even bigger life expectancy increase of approximately 3.3 years.
The Director of EPIC and one of the study's lead authors, Michael Greenstone, commended "We don't have a historical example of a country achieving such rapid reductions in air pollution. It's remarkable.”
Moreover, China’s rapid increase in life expectancy in the last 40 years should also be acknowledged.
In 1980 when China began its new industrialization under its opening and reform policy which brought about the higher levels of air pollution, life expectancy was 65.5 years. By 2015 it had increased to 76.1 years; moving China from 79th place in the world up to 55th place.
And life expectancy in Beijing is not far behind at about 82 years.
So, clearly, while China's industrialization did bring higher levels of air pollution it has also brought benefits which have helped to improve people's health in China.
Air pollution in China continued to fall in 2018, but it is still higher that China's own ambient air quality standard calling for the annual average PM2.5 concentration to be within 35 ug/m3. Further efforts in the war on air pollution, therefore, are needed to improve the health of residents in China.
EPIC's ongoing research notes that China's average life span could increase by a further 3 years if the country could bring its average annual PM2.5 concentration down to the World Health Organizations (WHO) standard of 10 ug/m3.
This, however, will be extremely hard to accomplish as Jiang Kejun, a research professor at China's Energy Research Institute noted; "It would be very difficult for China to meet the WHO standards even with strong efforts to reduce industrial emissions and fossil fuel consumption. Emissions from non-industrial sectors, agriculture for instance, also play a big part in air pollution and are hard to put under control.”
Expats in China, therefore, should continue to use air pollution solutions to protect their health while the battle for blue skies in China continues.
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