95% of World's Population Breathes Unsafe Air

A report released Tuesday found that 95 percent of the world's population is exposed to dangerous levels of air pollution, CNN reported.

The Health Effects Institute's (HEI) yearly State of Global Air report said that the outdoor air where 95 percent of humans live has particulate matter concentrations above the Word Health Organization's (WHO) air quality guidelines of 10 micrograms per square meter. Almost 60 percent live in areas where particulate matter exceeds even the WHO's less-strict transitional guidelines of 35 micrograms per square meter.

A map comparing particulate matter concentrations to WHO guidelines and interim targetsHEI

The report also looked at household air pollution caused by burning fuels in the home for cooking and heating and found that more than a third of the world's population is exposed to this type of air pollution as well, which can exceed WHO guidelines by a factor of 20.

The report found that the highest concentrations of air pollution, weighted for population, were in North Africa, West Africa and the Middle East. The next highest concentrations were in South Asia, especially Bangladesh, Nepal, India and Pakistan. The countries with the healthiest air were Australia, Brunei, Canada, Estonia, Finland, Greenland, Iceland, New Zealand, Sweden and countries in the Pacific islands.

Overall, global air pollution has gone up by 18 percent between 2010 and 2016, the least year for which data was available. In China, which has made a concerted effort to combat pollution, levels have actually slightly declined in the six year period, though they are still above the WHO interim target at 56 micrograms per square meter. Bangladesh, Pakistan and India have seen the largest increase in air pollution during the same period..

The report comes as public health researchers are finding more and more health risks associated with long-term exposure to air pollution. Most recently, scientists found that exposure to air pollution in Mexico City increased the risk that the city's young people would develop Alzheimer's.

The HEI study found that air pollution caused 4.1 million deaths from heart disease, stroke, lung cancer, chronic lung disease and respiratory infections in 2016. China and India bore the brunt of the health impacts of air pollution, accounting for 51 percent of the world's air pollution related deaths that year.

The number of deaths per country due to air pollution in 2016.HEI

HEI Vice President Bob O'Keefe told The Guardian that the report showed a growing gap between the most polluted developing countries and the least polluted wealthier ones. That gap has increased from six-fold to 11-fold between 1990 and 2016.

However, O'Keefe said the report was not all doom and gloom. "There are reasons for optimism, though there is a long way to go. China seems to be now moving pretty aggressively, for instance in cutting coal and on stronger controls. India has really begun to step up on indoor air pollution, for instance through the provision of LPG [liquefied petroleum gas] as a cooking fuel, and through electrification," he told The Guardian.