Masks can cut air pollution risks.
http://www.environmentalhealthnews.org/ehs/newscience/2012/01/2012-0402-masks-reduce-air-effects/
"Face masks can help protect those with coronary heart disease (CHD) from symptoms and health effects triggered by exposure to polluted air, a study from Beijing, China finds. Heart disease symptoms and blood pressure were both reduced when older men and women diagnosed with CHD wore the masks while walking in the city. The masks effectively filtered out almost all of the harmful fine and ultrafine particles released from cars and other traffic in the urban area."
http://www.environmentalhealthnews.org/ehs/newscience/2012/01/2012-0402-masks-reduce-air-effects/
"Face masks can help protect those with coronary heart disease (CHD) from symptoms and health effects triggered by exposure to polluted air, a study from Beijing, China finds. Heart disease symptoms and blood pressure were both reduced when older men and women diagnosed with CHD wore the masks while walking in the city. The masks effectively filtered out almost all of the harmful fine and ultrafine particles released from cars and other traffic in the urban area."
