Summertime, and the breathing's not easy. Hot and hazy means there's something unhealthy in the air. One out of ten Americans live in areas with unhealthy levels of air pollution, according to the American Lung Association's State of the Air 2008 report. The smoke and soot from wildfires in California and North Carolina contain fine particulate matter, also produced by coal-burning power plants, cars and trucks.

Sudden spikes in particles smaller than 10 microns (PM10), which can penetrate deep into the lungs, have led to cardiopulmonary deaths within the following 24 to 48 hours, a study revealed this year. Pregnant women's exposure to PM10 has also been associated with lower birth weights in their babies. Prolonged exposure to combustion byproducts known as polycyclic aromatic hydrocarbons (PAHs) can cause cancer (in addition to the aforementioned, sources include charred meat and barbecues).

Then there's bad old smog, formed by the action of sunlight and high temperatures upon air pollutants and containing toxic ozone gas, according to the U.S. Environmental Protection Agency. Smog can trigger everything from asthma to sudden heart attacks.

Makes you afraid to inhale, doesn't it? Even the healthiest among us can choke up in hot, humid, dirty air, but it can really hurt sensitive groups such as young children, the elderly, and those with asthma, heart disease and diabetes. What to do?

* Check for air quality alerts in local media, or enter your state at EPA's Air Now site, which gives levels of ozone and PM. Code Orange means levels are unhealthy for sensitive groups (USG). 

* During Code Orange or Red days, keep outdoor exercise to a minimum. Close windows and turn on air conditioners, or go to an air conditioned place.

* Even on clean ambient air days, keep outdoor exercise to non-rush-hour times and at least 100 yards from major roads, where levels of ozone and PM are always higher.

* Keep air conditioner filters clean and changed regularly, and consider getting a vaccuum cleaner with a HEPA filter, which traps PM.

* Do your part to reduce air pollution by conserving energy at home and driving less and, well, smarter.

* Write your Congressional delegation urging them to support legislation forcing dirty old power plants to clean up their act.

* Take a bad air day. Head for the beach or the mountains. You deserve it, and so do your hardworking lungs!

This article originally appeared in Plenty in July 2008. The story was added to

Copyright Environ Press 2008