By Natasha Baker
TORONTO, July 2 (Reuters) - Worried about breathing polluted air? A new app shows users the air quality in their area and lets them know when it might be best to stay indoors.
State of the Air, a free app released by the American Lung Association, provides real-time updates on levels of ozone and particulate pollution in the atmosphere -- the two most widespread air pollutants, and among the most dangerous, in the United States.
"More than 127 million people live in areas of the country where there are dangerous levels of ozone and particulate pollution, which are the two key pollutants that we address in our new smartphone app," said Carrie Martin Munk, a former vice president of communications and marketing for the American Lung Association.
"We really wanted to empower individuals with the tools that can help them live healthier lives."
Ground-level ozone, produced by emissions from industrial plants, electric utilities and motor vehicle exhaust, is one of the most common air pollutants, causing lung irritation and other health concerns.
Particulates, a mix of breathable bits of soot, exhaust, metals and chemicals, are detrimental to both the heart and lungs and among the most dangerous air pollutants.
Air quality data within the app is provided by the Environmental Protection Agency (EPA) and includes current pollution levels, as well as forecasts for later in the day and the following day.
Along with pollutant levels, the app provides alerts based on the Air Quality Index (AQI), which is a scale showing how clean or polluted the air is. Based on the AQI, the app provides guidelines on whether it might be best to cut back on outdoor activities, especially for at-risk individuals.
"It's especially valuable for moms whose kids have asthma for when they have after-school soccer practices to know what kind of air they're going to be dealing with and to make decisions for a healthier life," Munk said.
Although healthy individuals are affected by poor air quality, people suffering from a range of illnesses are especially at risk to its negative health effects.
"Often times poor air quality can mean life or death to people who are suffering from lung disease, like asthma or COPD, people with heart disease, diabetes, older adults and even children," Munk said.
Users can also share the quality of the air through the app to Facebook, Twitter and email, which the association hopes will raise awareness about air pollution.
"It's an interesting challenge to raise people's awareness about the air -- because you can't see pollutants," Munk said.
The American Lung Association also releases the State of the Air report online each year. It provides a historical look and gives a grade for air pollution in cities across the United States.
Among the most polluted cities, according to the report, are Los Angeles, Bakersfield, and Fresno, all in California. Santa Fe, New Mexico; Cheyenne, Wyoming, and Prescott, Arizona, are among the cleanest cities.
The free app is available in the United States for iOS and Android devices. (Editing by Patricia Reaney and John Wallace)