Why should I worry about PM?

• PM causes lung problems, from shortness of breath to worsening of respiratory and cardiovascular disease, damage to lung tissues, and cancer. People of highest risk of these effects include asthmatics, individuals with chronic heart or lung disease, as well as children and the elderly.
• Ultrafine PM (PM10) easily makes its way past the upper airway, and penetrates into the deepest tissues of the lungs, where accumulation can occur. These particles, and the chemicals absorbed to their surface, can then enter the blood stream; many of the chemicals are recognized human toxicants, carcinogens, reproductive hazards, or endocrine disruptors.
• PM decreases visibility, and causes aesthetic damage to buildings.
• There is no lower limit below which PM’s are safe.

Source - www.idontcareaboutair.com