The articles and links below show how negative ions benefit people.

Negative Ions and Ozone: Myths vs. Facts http://www.bright.net/~comtech/ions...yths_facts.html
Negative ions - Vitamins of the Air http://www.bright.net/~comtech/ions_vitamins.html
Negative ions and Computers http://www.bright.net/~comtech/negions_computers.html
Reader's Digest article: Ions Can Do Strange Things To You http://www.bright.net/~comtech/readersdigest_ions.html
Project: Air - Asthma and ions http://mypage.direct.ca/g/gcramer/asthma.html
An introduction to indoor air quality (EPA) http://www.epa.gov./iaq/ia-intro.html
Negative ions and the treatment of depression http://www.websciences.org/sltbr/yoa7395a.htm
Chronobiology and Depression Home Page http://www.lightandions.org/
Negative Ion Therapy Page http://www.cet.org/ions.htm

News

It now appears that the exact relationship of melatonin (and perhaps serotonin) to seasonal depression - if any - is unconfirmed. Recently, researchers have suggested that the issue may be, not the actual levels, but how a lack of negative ions and/or light might disrupt the cycle of production of these brain chemicals. More research needs to be done in this area.

Hope you find something useful,
Doreen