Air pollution prevention has saved 46,000 Chinese people in five years

From 2013 to 2017, about 46,000 people in China avoided suicide due to air pollution control, accounting for about ten percent of the total reduction in suicide cases. Researchers quantified for the first time the relationship between PM 2.5 particulate air pollution and suicide incidents, and concluded that fine dust is most dangerous to the mental health of older women. The results of their study are published in the population journal Nature Sustainability.

Every year, more than 700,000 suicides are committed worldwide. People are pushed to them by reasons related to economic, social, cultural and natural factors, which in many ways have yet to be studied. China, where up to 16 percent of suicides occur, but where the number of suicides has declined dramatically in recent decades, may be a good place for such a study. The country is also interesting for the marked improvement in air quality it has seen in recent years, with a number of epidemiologic and neurobiologic studies suggesting a link between air pollution and suicide.

A team of scientists from China and the United States, led by Peng Zhang of the Chinese University of Hong Kong and Tamma Carleton of the University of California, Santa Barbara, has for the first time quantified the link between PM2.5 (fine particulate matter) air pollution and suicide in China. Because changes in air quality affect not only human health but also economic performance, the researchers used a statistical model that accounts for short-term changes in particulate matter concentration in the air following meteorological indicators (temperature inversions) rather than long-term industry shifts.

It turns out that as PM2.5 concentrations increase by one standard deviation, the number of suicides per week increases by 0.24 ± 0.09 per million (p = 0.006). This represents a jump of 25 percent over the weekly average, with this trend across 597 counties in China in different seasons and for populations with different income levels. Analysis of the heterogeneity in the association between air pollution and suicide showed that people aged 65-85 years were most vulnerable to exposure to PM2.5 particles, and especially women: in women over 65, for every microgram of PM2.5 in the air, the number of suicides per week increased by 63 percent relative to the average in this category (p = 0.007). The authors calculated that government efforts to reduce industrial emissions prevented 45,970 ± 16,712 suicides in China from 2013 to 2017.

Clean air makes populations not only healthier, but also more satiated. Scientists recently found that lowering the concentration of ground-level ozone in the air to a tolerable level increases corn yields in China by nearly eight percent.