Hi! What are the effects, both positive and 'negative' of a negative ion generator?

They take oders out of the air.

you get a better result by having the window open and letting fresh, clean, air into your home. if you don't have access to such air you may be inclined to using the generator. the independent test results have been mixed.

Ionizers are great air cleaners indoors. Dust particles in the air are charged with a static electricity. They are attracted together like magnets, become heavy and drop to the floor or attach to a surface with opposite charge. That's how the Ionic Breeze works. The plates are positive and the ionizer shoots a static charge in the air. As the air passes the plates, particles attach to the metal surface. Ions are abundant in the air near water and the earths surface in natural areas. This is why a walk in the forest or on the beach is refreshing. Other chemicals are also cleaned from the air with ionizers. Indoor pollution levels are greater than outdoors. Plastics and chemical bottles in the house, (especially in winter when windows are closed), out gas dangerous chemicals. These low level chemical have an accumulative negative effect on our health. The body can not tolerate many chemicals or deal with them at all. They stay in the body and increase in concentration as we are exposed, like lead and mercury. CRT monitors are statically charged. Have you noticed black dust collecting by them?