Candles: A Burning Question
Part 1

Many of us burn candles to relax, to set a mood and freshen the air. In fact, the candle industry sells more than a billion dollars in scented candles every year.

But where there's fire, there's smoke.

Have you ever wondered about that stream of smoke you see occasionally when you burn a candle? You may be surprised and concerned when you hear what the experts are saying about it.

As hard as she's washed, scrubbed and bleached, Mindy Wright can't get this mysterious grey stuff off her lights, walls or windows.

It built slowly and evenly in corners, along the framework, so subtlely that the walls just look dirty.

When the lights are on, the marks are hard to see. Turn them off, and it looks like smoke damage.

But Mindy isn't a smoker. She doesn't have a fireplace and her furnace was just checked. But she does burn scented candles.

Mindy Wright: "I WOULD TRIM THE WICKS LIKE THEY TELL YOU TO, AND THERE WAS STILL BLACK SMOKE BURNING. AND I WOULD BURN THEM LESS FREQUENTLY, AND OVER SEVERAL MONTHS I NOTICED MORE AND MORE BLACK."

A few miles away, the same gray stuff showed up on Heather Peterson's walls. She's since repainted.

But inside closets where she tried bleaching it out, in some spots it just won't go away.

Heather Peterson: "I HAD PEOPLE FROM SALT LAKE COME UP, PEOPLE FROM THE HEALTH DEPARTMENT, PEOPLE FROM THE MICROBIOLOGY LAB AT UTAH STATE, ALL JUST RUNS TONS OF TESTS AND TAKE SAMPLES."

Heather doesn't have a fireplace or a wood burning stove, and investigators ruled out her furnace and her ventilation system -- everything BUT her scented candles.

Heather Peterson: "I'D HAVE TWO OR THREE CANDLES GOING SOMETIMES." "HOW LONG?" "I'D ALWAYS HAVE ONE GOING. I'D LIGHT IT IN THE MORNING AND THEN BLOW IT OUT AT NIGHT."

In fact, state air quality experts found candle soot on nearly every surface in her home.

Bruce Allen/Utah Air Quality: "THE SOOT WOULD DEPOSIT ON THE COLDER PARTS OF THE WALL. IT'S THERMAL BRIDGING OR GHOSTING, AS IT'S OFTEN CALLED."

That same ghosting covered the walls inside Terry Allen's home. She was surprised when she heard her scented candles were a likely cause.

Terry Allen: "IT WAS SO BLACK, AND IT LOOKED LIKE OUR HOUSE WAS A JAILHOUSE."

Stacey Butler/Eyewitness News: "YOU'VE PROBABLY NEVER HEARD BEFORE THAT BURNING CANDLES CAN CAUSE THAT KIND OF DAMAGE. THAT'S BECAUSE PEOPLE ARE JUST FINDING OUT HOW SIGNIFICANT THIS PROBLEM IS. IN FACT, JUST A FEW DAYS AGO, THE ENVIRONMENTAL PROTECTION AGENCY RELEASED A STUDY OF CANDLE SOOT -- AND IT CONTAINS SOME UNSETTLING ANSWER TO SOME BURNING QUESTIONS."

The key finding-- "It is now believed that frequent candle burning is one of the sources of black soot." And, sooting can cause property damage by blackening surfaces.

The phenomenon is called ghosting, carbon tracking and dirty house syndrome.

Homes with black soot deposition often have stained carpets, and the particles are electrically charged to freezers and other plastic surfaces.

The study finds "complaints have risen sharply as the popularity of scented candles has spiked."

And few know more about the problem than Indoor Air Quality expert, David Krause, who began his candle research after more and more homeowners in Florida complained of the strange shadowing in their homes.

David Krause: "THE SOOT GENERATED FROM A CANDLE IS INDISTINGUISHABLE ON A MICROSCOPIC SCALE FROM DIESEL GENERATED BY A DIESEL TRUCK."

We spoke to several candle manufacturers, who all say they are unaware of any serious problems with soot from their products.

If you are concerned about a problem, here is some advice from experts:

• The more fragrance in the candle the more soot is created.

• The longer you burn a candle, the greater the chances of a problem.

• The larger the candle, the greater potential for soot.

• The same goes for the wick. Experts advise that you keep it trimmed -- under a quarter inch -- to reduce the problem.

E.P.A. Study