Worse Air Pollution Found to Decrease Happiness Levels

Another reason that the world should convert to renewable, clean sources of power in the fight against climate change. Happiness is one of the most important things in life, and therefore it’d be good if the world’s political systems better prioritized the general happiness of people instead of largely prioritizing big business profits.

Now researchers at MIT have discovered that air pollution in China’s cities may be contributing to low levels of happiness amongst the country’s urban population.

In a paper published in the journal Nature Human Behaviour, a research team led by Siqi Zheng, the Samuel Tak Lee Associate Professor in MIT’s Department of Urban Studies and Planning and Center for Real Estate, and the Faculty Director of MIT China Future City Lab, reveals that higher levels of pollution are associated with a decrease in people’s happiness levels.

The paper also includes co-first author Jianghao Wang of the Chinese Academy of Sciences, Matthew Kahn of the University of Southern California, Cong Sun of the Shanghai University of Finance and Economics, and Xiaonan Zhang of Tsinghua University in Beijing.

Despite an annual economic growth rate of 8 percent, satisfaction levels amongst China’s urban population have not risen as much as would be expected.

Alongside inadequate public services, soaring house prices, and concerns over food safety, air pollution — caused by the country’s industrialization, coal burning, and increasing use of cars — has had a significant impact on quality of life in urban areas.

Research has previously shown that air pollution is damaging to health, cognitive performance, labor productivity, and educational outcomes. But air pollution also has a broader impact on people’s social lives and behavior, according to Zheng.

To avoid high levels of air pollution, for example, people may move to cleaner cities or green buildings, buy protective equipment such as face masks and air purifiers, and spend less time outdoors.

“Pollution also has an emotional cost,” Zheng says. “People are unhappy, and that means they may make irrational decisions.”

On polluted days, people have been shown to be more likely to engage in impulsive and risky behavior that they may later regret, possibly as a result of short-term depression and anxiety, according to Zheng.

“So we wanted to explore a broader range of effects of air pollution on people’s daily lives in highly polluted Chinese cities,” she says.

To this end, the researchers used real-time data from social media to track how changing daily pollution levels impact people’s happiness in 144 Chinese cities.

In the past, happiness levels have typically been measured using questionnaires. However, such surveys provide only a single snapshot; people’s responses tend to reflect their overall feeling of well-being, rather than their happiness on particular days.

“Social media gives a real-time measure of people’s happiness levels and also provides a huge amount of data, across a lot of different cities,” Zheng says.

The researchers used information on urban levels of ultrafine particulate matter — PM 2.5 concentration — from the daily air quality readings released by China’s Ministry of Environmental Protection. Airborne particulate matter has become the primary air pollutant in Chinese cities in recent years, and PM 2.5 particles, which measure less than 2.5 microns in diameter, are particularly dangerous to people’s lungs.

To measure daily happiness levels for each city, the team applied a machine-learning algorithm to analyze the 210 million geotagged tweets from China’s largest microblogging platform, Sina Weibo.

The tweets cover a period from March to November 2014. For each tweet, the researchers applied the machine-trained sentiment analysis algorithm to measure the sentiment of the post. They then calculated the median value for that city and day, the so-called expressed happiness index, ranging from 0 to 100, with 0 indicating a very negative mood, and 100 a very positive one.

Finally, the researchers merged this index with the daily PM2.5 concentration and weather data.

They found a significantly negative correlation between pollution and happiness levels. What’s more, women were more sensitive to higher pollution levels than men, as were those on higher incomes.

When the researchers looked at the type of cities that the tweets originated from, they found that people from the very cleanest and very dirtiest cities were the most severely affected by pollution levels.

Plants Can Absorb Toxins, Increasing Indoor Air Quality

Air quality is an important aspect of indoor environments, yet there is surprisingly little research on optimizing the role of plants for increasing that air quality, and even how plants can absorb indoor toxins doesn’t seem widely known.

People in industrialized countries spend more than 80% of their lives indoors, increasingly in air-tight buildings. These structures require less energy for heating, ventilating, and air conditioning, but can be hazardous to human health if particulate matter and potentially toxic gases, including carbon monoxide, ozone, and volatile organic compounds, from sources such as furniture, paints, carpets, and office equipment accumulate. Plants absorb toxins and can improve indoor air quality, but surprisingly little is known about what plants are best for the job and how we can make plants perform better indoor.

[…]

Plants improve air quality through several mechanisms: they absorb carbon dioxide and release oxygen through photosynthesis, they increase humidity by transpiring water vapor through microscopic leaf pores, and they can passively absorb pollutants on the external surfaces of leaves and on the plant root-soil system. But plants are usually selected for indoor use not for their air-purifying abilities but for their appearance and ability to survive while requiring little maintenance.

Study: 95% of World Population Exposed to Harmful Air Pollution

It’d thus be a good idea to redesign the energy systems of the world to use clean energy instead of fossil fuels such as oil and coal. Last year a major study found that pollution caused 9 million deaths and lead $4.6 trillion in damages annually.

More than 95 percent of people worldwide are exposed to dangerous air pollution, which kills millions each year and threatens billions more, according to a new analysis.

State of Global Air 2018: A Special Report on Global Exposure to Air Pollution and Its Disease Burden (pdf), published by the Health Effects Institute (HEI), details how exposure to air pollution—both indoor and outdoor—poses a mounting threat to public health.

Researchers found that air pollution is the top environmental cause of death globally, and ranks fourth overall among risk factors —behind high blood pressure, smoking, and dietary choices.

Household air pollution and ambient particular matter—a component of outdoor pollution—were listed individually among the top ten risk factors, and were tied to a combined 6.7 million deaths in 2016, the last year studied. Ozone, a harmful gas that contributes to outdoor pollution, was listed separately and tied to 234,000 deaths from chronic lung disease.

The study, said HEI president Dan Greenbaum, “leads a growing worldwide consensus—among the WHO, World Bank, International Energy Agency and others—that air pollution poses a major global public health challenge.”

“Nowhere is that risk more evident than in the developing world,” Greenbaum noted, “where a third of the world’s population faces a double burden of indoor and outdoor air pollution.”

The report found that “the elderly in low- and middle-income countries experience the greatest loss of healthy life-years due to the non-communicable diseases” linked to air pollution, such as cardiovascular disease, stroke, lung cancer, and COPD.

The new analysis comes as the Trump administration moves to scale back air pollution protections to cater to U.S. manufacturers, part of the administration and Environmental Protection Agency’s broader deregulatory agenda.

Recent studies have shown that similar to the rest of the world, non-White Americans and those living in poverty are more likely to be exposed to polluted air.