Negative Ion Generators were evidently the rage in the late 70's and early 80's. Mine was a gift from a retiring alternative medicine practitioner who was cleaning out her storage unit of old smudge sticks, Grateful Dead posters, and Negative Ion Generators.
Ions are molecules that have gained or lost an electrical charge. . They are created in nature when air molecules break apart due to sunlight, wind, and radiation.
Negative ions are the odorless, tasteless, and invisible molecules that we inhale in certain environments, such as by waterfalls or the ocean. Negative ions are believed to increase levels of Serotonin, helping to alleviate depression, relieve stress, and boost energy.
There is no doubt that a negative ion generator will reduce the amount of particulates, such as dust or smoke in the air. This can be dramatically demonstrated using a bell jar full of smoke and a negative ion generator - When you turn it on, the smoke disappears almost instantly. Dust falls to the lowest surface.
Whether negative ion generators can be successfully used to treat depression is still open to discussion. I can tell you that since I have had my negative ion generator, I have generally been a happy and contented person. I should probably disclose that I was generally happy before I had my Modulion, and frequently it is not plugged in if I need the power outlet for something else.
When I feel illness coming on, or if I need to be at peak performance level, I try to get a lot of sleep, take a long shower, eat a good breakfast, take a quality multivitamin and some fish oil, and I crank up the negative ion generator. I will accept whatever benefit or positive placebo effect might be provided - I am not willing to take a chance (In Singapore, this personality trait is called being 'Kiasu').
One drawback of negative ion generators is that they may create static electricity resulting in small shocks when you touch certain objects.