Even low levels of air pollution can be deadly
Source: https://www.earth.com/news/even-low-levels-of-air-pollution-can-be-deadly/
Author: Andrei Lonescu
In 2016, the World Health Organization (WHO) estimated that over 4.2 million people die prematurely each year from long-term exposure to fine particulate outdoor air pollution (known in the scientific community as PM2.5). However, a new study led by McGill University in Canada suggests that the yearly global death toll from air pollution may be significantly higher than previously thought, and that mortality risk was increased even at very low levels of PM2.5 – which can lead to cardiovascular and respiratory diseases, as well as some types of cancers. The scientists arrived at this conclusion by combining health and mortality data for a cohort of seven million Canadians gathered over a period of 25 years with information about the levels of pollution across the country. Since Canada is a country with low levels of outdoor PM2.5, it is the perfect place to study health impacts at low concentrations. While the WHO recently set out ambitious new guidelines for annual average air pollution, reducing by half its earlier recommendations – from concentrations of 10 to concentrations of five micrograms per cubic meter – the current standards of the U.S. Environmental Protection Agency are 12 micrograms.