Air Cleaning System Could Destroy Anthrax

An indoor air cleaning system developed to zap dust mites and mold spores also destroys airborne anthrax and other pathogenic microbes, says the University of Florida (UF) engineering professor who pioneered the technology.

The system has been tested against a close cousin of the anthrax bacteria and could be installed in office and home heating and air conditioning systems at low cost, said Yogi Goswami, a UF professor of mechanical engineering and director of UF's Solar Energy and Energy Conversion Laboratory. "There are other technologies for air cleaning, but for air disinfection, there is no more effective system."

The air cleaning system relies on the interaction between light and titanium dioxide, a common chemical. When light is absorbed into the titanium dioxide, it acts as a catalyst to produce an oxidizing agent.

The agent, called a hydroxyl radical, "is like a bullet for the bacteria," Goswami said, destroying dust mites, mold spores and pathogens by disrupting or disintegrating their DNA.

Goswami came up with the system in the mid 1990s as a cure for sick building syndrome, when poor ventilation and a build up of mold or mildew cause illnesses for people who work inside. Initial research proved that the system kills the mold spore aspergillus niger, considered to be one of nature's hardiest spores, he said.

More recent research has shown that the system also destroys bacillus subtilis, a spore that causes