HOUSTON -

The World Health Organization (WHO) reports around 7 million died as a result of air pollution exposure in 2012. That is one in eight of the total global deaths.

WHO said this recent finding more than doubles previous estimates. Air quality season is just getting started, and this week is Air Quality Awareness Week.

We have heard a lot about ozone and even have ozone alert days issued by the National Weather Service. But we also need to be concerned with particulate matter.

"A lot of the evidence has been suggesting the most deadly consequences come from the smaller particles because those small particles are the ones that can deeply penetrate into the lungs," explained Dr. Daniel Cohan, Professor of Environmental Engineering at Rice University.

According to the WHO, heart disease and stroke top the list of outdoor air pollution caused deaths.

Here is the breakdown:
•    40% – ischaemic heart disease;
•    40% – stroke;
•    11% – chronic obstructive pulmonary disease (COPD);
•    6% - lung cancer; and
•    3% – acute lower respiratory infections in children.

"The risks from air pollution are now far greater than previously thought or understood, particularly for heart disease and strokes," says Dr Maria Neira, Director of WHO’s Department for Public Health, Environmental and Social Determinants of Health. "Few risks have a greater impact on global health today than air pollution; the evidence signals the need for concerted action to clean up the air we all breathe."

So what is particulate matter and where does it come from? The answer is complex.

"When we say ozone, that always means three ozone atoms in a molecule." explained Cohan. "But when we say particulate matter, it could really mean a whole range different sizes; it could mean a whole range of different chemicals, like organic carbon, sulfates, nitrates."

Some particulates come from nature like volcanoes or pollen.

Some sources are manmade like cars and factories.

All of these particles combine together to make up this broad, umbrella category called particulate matter.

But the particulate matter we need to be most concerned with according to Cohan are those that have a diameter of 2.5 microns or smaller. (A micron is a millionth of a meter.)

"Health researches find that the very simple measure of 2.5 is very highly correlated with health effects and very highly correlated with death rates," said Cohan.

To better get an idea of air quality across Houston, Rice University has teamed up with atmospheric scientists at the University of Houston to operate a mobile lab.

The lab will roam the streets of Houston's neighborhoods and gather data on particulate matter.

They will then compare that data to health records collected over the past decade by the University of Texas Health Science Center at Houston.

They are hoping to identify neighborhoods that are most at risk from poor air quality and especially particulate matter.

So far, University of Houston's Barry Lefer said they have sampled the Conroe area and the Woodlands very well.

He adds they have done a lot of work in Sugar Land and hope to drive around Westside over the summer.

Find Out Your Air Quality

•AirNow.gov: http://www.airnow.gov/index.cfm?action=airnow.local_city&cityid=236
•Real-time ozone conditions: http://houstoncleanairnetwork.com/
•TCEQ Ozone Measurements: http://www.tceq.texas.gov/agency/data/ozone_data.html
•TCEQ Particulate Matter Measurements: http://www.tceq.texas.gov/agency/data/pm25.html
•TCEQ Air Quality Alerts And Forecasts: http://www.tceq.texas.gov/airquality/monops/ozone_email.html

Taking Action This Week

The EPA has suggestions for the rest of the week to reduce your contribution to air pollution:

Walk Somewhere Wednesday: Walk to nearby locations instead of driving. Increasing the number of steps you take will improve your health.

No Drive-Thru Thursday: Avoid the drive-thru and go inside to order your food, coffee or prescriptions. By doing this you will reduce exhaust emissions.

Fuel After Dark Friday: Hot temperatures and gasoline fumes create ground-level ozone. Reduce the effect and refuel your vehicle at night time.

Sweep It Up Saturday: Sweep your driveway, patio, deck, etc. instead of using a leaf blower. Get some exercise and breathe in fresh air while you burn a few calories.