Photocatalytic Air Cleaning System Promises To Help Allergy Sufferers

October 9, 1997

GAINESVILLE — Allergy and asthma sufferers soon may have a new weapon in their fight against airborne enemies: an indoor-air cleaning system that uses light and simple chemicals to destroy the dust mites and mold spores that cause many allergies.

Developed at the University of Florida’s Solar Energy and Energy Conversion Laboratory, the photocatalytic air filtration system has been tested in medical and industrial settings and already has proven successful at zapping odors and impurities caused by chemicals, viruses and bacteria. It soon will be available for home use, said Yogi Goswami, professor and director of the laboratory.

“This technology will revolutionize our notions about the quality of indoor air,” said Goswami. “With people spending more and more time indoors, it becomes increasingly important to provide clean air.”

The system uses light, which reacts with a titanium dioxide-based chemical catalyst as air passes through. The result is oxidation, which attacks and destroys microbes by disintegrating their DNA. The reaction also kills dust mites and mold.

Goswami said that the photocatalytic process is superior to conventional techniques using filters, which must be changed and disposed of.

“With this system, contaminants are destroyed rather than transferred. No toxic chemicals are employed,” said Goswami. Allergy and asthma suffers may find great relief once dust mites and mold spores are eliminated from the air they breathe, he said.

“Dust mites in the air cause allergic reactions in an estimated 15 to 20 percent of the population, and have been linked to the development of childhood asthma. The droppings of dust mites live in bedding and carpeting, but they also circulate in the air,” said Goswami.

“Inhaled mold spores are also responsible for many allergy symptoms and aggravate asthma. Mold seeds are microscopic and need to be 100 percent destroyed. Otherwise they lie dormant and grow back. Because mold spores also circulate in the air, cleaning an environmental surface is not an efficient way of eliminating molds. This system eliminates molds altogether.”

Goswami said the system has been tested successfully in medical research settings where the air in laboratories must be microbe-free.

“We’ve tested the photocatalytic air cleaning system on a variety of indoor air problems, including toxic bacteria, such as those found to cause Legionnaire’s disease,” said Goswami. “Surgical suites and hospital nurseries are just two obvious places for this system. Sick building syndrome will be a thing of the past where this system is used. The photocatalytic system can quickly kill off 100 percent of bacteria in indoor air,” said Goswami.

The technology is being readied for the market by Universal Air Technology at the Sid Martin Phototechnology Development Institute, a biotechnical business incubator of the University of Florida. The home units, Goswami said, may cost as little as $500.