Problems with Ozone Generators

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Problems with Ozone Generators

http://www.lungusa.org/site/pp.asp?c=dvLUK9O0E & b=39310

Ozone is a potent lung irritant and exposure to elevated levels is a

contributor to the exacerbation of lung disease; it is especially

dangerous for persons with asthma and other chronic lung diseases,

children, and the elderly. Residential indoor ozone is produced

directly by ozone generators and indirectly by ion generators and

some other electronic air cleaners. There is no difference, despite

some manufacturers' claims, between outdoor ozone and ozone produced

by these devices.

The Federal Trade Commission (FTC) took action in 1995 against two

manufacturers of ozone generating devices. The FTC charged that they

made unsubstantiated claims about the ability of their products to

clean air of various indoor air pollutants and to prevent or relieve

allergies, asthma and other conditions. Under the FTC's settlement,

the manufacturers are prohibited from making marketing claims that

ozone is effective in cleaning indoor air, that their products do

not create harmful by-products, and that they prevent or provide

relief from allergies, asthma, and other specified conditions,

unless the claims are supported by reliable and adequate

substantiation (FTC, 1995).

Consumer Reports (1992), the National Institute of Occupational

Safety and Health (NIOSH) (Boeniger, 1995), and the U.S. EPA (1995)

concluded that tabletop and room unit ozone generators are not

effective in improving indoor air quality. Studies have found that

while some indoor air pollutant concentrations decline in the

presence of ozone, other pollutants increase. In fact, upon reaction

with ozone, some previously undetected, toxic chemicals emerge in

indoor air, including formaldehyde and other aldehydes (Boeniger,

1995). There is a lack of evidence in the scientific literature that

would support the effectiveness of ozone at low concentrations in

removing organic contaminants from indoor air (Boeniger, 1995). A

recent study by the U.S. EPA demonstrates that ozone is not

effective for killing airborne molds and fungi even at high

concentrations (6-9 ppm) (U.S. EPA, 1995). At higher concentrations,

especially above 0.08 ppm, ozone is a potent irritant that can bring

about diminished lung function, cough, inflammation associated with

biochemical changes, and increased responsiveness to allergens.

(Horstman, et al., 1990). Current evidence of the health effects of

ozone suggests that there is no " safe " threshold concentration for

the onset of health responses due to exposure above background ozone

concentrations (Burnett, et al., 1994; U.S. EPA CASAC letter, 1995).

Also, simultaneous exposure to ozone and other compounds may produce

additive or synergistic effects (Last, et al, 1984). In addition,

persons with asthma have increased susceptibility to ozone and

exposure to low concentrations results in increased symptoms,

medications use and hospitalizations.

The FDA has set a limit of 0.05 ppm of ozone for medical devices. A

small percentage of air cleaners that claim a health benefit are

listed by the FDA and these devices conform to FDA regulations.

However, ozone generators, negative ion generators, and certain

other electronic air cleaners that are not listed by the FDA, or

cannot otherwise prove that their ozone emission levels are lower

than 0.05 ppm, may produce levels of ozone recognized as unsafe for

humans and are not recommended for use in occupied spaces because of

the risk of generation of ozone. For similar reasons, the American

Lung Association does not suggest the use of these products.