Bay Area residents are being encouraged to carpool, bike, walk or take public transportation to work Wednesday because of a Spare the Air alert, the Bay Area Air Quality Management District announced today.

Citing unhealthy air quality forecast for Wednesday, the district issued its 19th alert for the region this year.

Hot temperatures and light winds combined with motor vehicle exhaust from traffic is expected to create unhealthy ozone accumulation throughout the Bay Area, district officials said.

"Exhaust from the millions of cars on Bay Area roads will cause unhealthy air quality on Wednesday," air district executive officer Jack Broadbent said in a statement. "Even a short heat wave reminds us that we need to make necessary changes to our commute to reduce pollution every day like carpooling, biking and walking."

Ozone, also known as smog, is linked to throat irritation, congestion and chest pain. It can also trigger asthma and inflammation in the linings of the lungs, as well as worsen bronchitis and emphysema, district officials said.

Long-term exposure to ozone pollution can cause reduced lung function. Young children, seniors and those with respiratory and heart conditions are most at risk, according to the district.

When Spare the Air alerts are in effect, residents are encouraged to perform outdoor exercises in the early morning hours when ozone concentrations are the lowest.

Additionally, residents are being discouraged from driving alone, not just on Spare the Air days, but every day in order to reduce unhealthy smog in the region, district officials said.

For a list of transportation programs available to commuters throughout the Bay Area, residents can visit stacommutetips.org.

To find out when Spare the Air alerts have been issued, residents can visit sparetheair.org, call 800-HELP-AIR, or download the Spare the Air mobile app on iTunes or Google Play.