SAN DIEGO -- When the fires raged on the ground, ash and smoke gathered in the air.

Building materials, plastics, chemicals, and electronics – those are some of the harmful substances that burned up and polluted the air San Diegans breathe.

Local lung experts told 10News that when the smoke clears there are lingering hazards, even now.

Kaiser pulmonary specialist Dr. David Levine said, "The air quality is still not going to be good for several weeks and people still need to be concerned."

Minute particles that remain in the air, or get stirred up by winds, are the chief danger, experts said.

"(Particles) can lodge deep down in the airways and is associated with a host of respiratory symptoms and sometimes even associated with an increase in heart attacks and cardiac events," said University of California, San Diego pulmonary specialist Dr. Smita Desai.

Levine added, "If they have symptoms they should see their doctor. And those symptoms can be eye irritation, nasal congestion, sore throat, and more serious things such as coughs, shortness of breath, wheezing like someone with asthma."

The county of San Diego's Air Pollution Control District monitors air quality and posts that information on its Web site.

"Cedar Fire studies from the 2003 fires showed that air quality was worse than normal for up to a month out," said Desai.

Ash on the ground is another concern.

After the fires, viewers wrote to 10News asking about the dangers of ash on fruits, vegetables and soil in their home gardens.

10News weathercaster and garden expert Loren Nancarrow offered some advice.

"We were under the smoke as much as anyone here in the North County so everything has been coated with a fine to thick cover of ash. I'm just treating as though it was poison so I'm washing it extra well," said Nancarrow. "Everything I've been able to find on the Internet says it you wash it off it, and this includes the county of San Diego, says if you wash it off it will be fine."

10News' Steve Atkinson asked Nancarrow, "We're talking about lingering effects of some of this stuff. If you till it up, is it still going to be in the soil? What does that do for the soil?"

"It will break it down. Micro-organisms will break it down. But from a gardener's point of view it really screws up the soil. Our soil is really alkaline and so we don't need to add anything that will make it more so and ash just sends it through the roof. What I'm going to be doing and recommending to people is taking household vinegar and spraying whole property and that will bring the PH back down," said Nancarrow.