WHO revises air quality norms for the first time since 2005

·        The World Health Organization has tightened global air quality guidelines in its first revision since 2005. The organization said air pollution is one of the "greatest environmental threats to human health".

·        Under the guidelines, WHO lowered recommended exposure levels for major pollutants including ozone, nitrogen dioxide, sulfur dioxide, carbon monoxide and particulate matter?

·        According to the WHO, exposure to air pollution causes 7 million premature deaths each year, as well as the loss of millions more healthy years of life.

Important facts

About WHO

v The World Health Organization is a specialized agency of the United Nations responsible for international public health. The WHO constitution states its main objective as "the attainment of the highest possible standard of health by all people".

v Headquarters: Geneva, Switzerland

v Founded: 7 April 1948