The AQLI is based on a pair of peer-reviewed studies co-authored by Greenstone that quantify the causal relationship between long-term human exposure to particulate pollution and life expectancy. The results from these studies are then combined with hyper-localized, global particulate matter measurements, yielding unprecedented insight into the true cost of air pollution in communities around the world. The index also illustrates how air pollution policies can increase life expectancy when they meet the World Health Organization’s guideline for what is considered a safe level of exposure, existing national air quality standards or user-defined air quality levels. This information can help to inform local communities and policymakers about the importance of air pollution policies in very concrete terms.
Seventy-five percent of the global population, or 5.5 billion people, live in areas where particulate pollution exceeds the WHO guideline. The AQLI reveals that India and China, which make up 36 percent of the world’s population, account for 73 percent of all years of life lost due to particulate pollution. On average, people in India would live 4.3 years longer if their country met the WHO guideline—expanding the average life expectancy at birth there from 69 to 73 years. In the United States, about a third of the population lives in areas not in compliance with the WHO guideline. Those living in the country’s most polluted counties could expect to live up to one year longer if pollution met the WHO guideline.
Globally, the AQLI reveals that particulate pollution reduces average life expectancy by 1.8 years, making it the greatest global threat to human health. By comparison, first-hand cigarette smoke leads to a reduction in global average life expectancy of about 1.6 years. Other risks to human health have even smaller effects: Alcohol and drugs reduce life expectancy by 11 months; unsafe water and sanitation take off 7 months; and HIV/AIDS, 4 months. Conflict and terrorism take off 22 days. So, the impact of particulate pollution on life expectancy is comparable to that of smoking, twice that of alcohol and drug use, three times that of unsafe water, five times that of HIV/AIDS, and more than 25 times that of conflict and terrorism.
“While people can stop smoking and take steps to protect themselves from diseases, there is little they can individually do to protect themselves from the air they breathe,” Greenstone said. “The AQLI tells citizens and policymakers how particulate pollution is affecting them and their communities and reveals the benefits of policies to reduce particulate pollution.”
The index stands apart from most work in this space in a few important respects. Previous efforts to summarize the health effects of air pollution have relied on associational studies that are prone to confounding the effects of air pollution with other determinants of human health. They also relied on extrapolations of associational evidence from the low levels in the United States or on extrapolations from cigarette studies. In contrast, the AQLI’s underlying research allows it to isolate the effect of air pollution from other factors that impact health and it does so based on pollution data at the very high concentrations that prevail in many parts of Asia today. Further, the AQLI delivers estimates of the loss of life expectancy for the average person, while other approaches report the number of people who die prematurely, leaving unanswered how much their life was cut short or if they were more predisposed to be impacted from it (e.g. elderly or sick).
To further explain the basis for the AQLI and showcase some of its top-level results, EPIC compiled a report that provides more information about particulate pollution, where it comes from and how it impacts the body.
—Article originally appeared on the Energy Policy Institute website