Maybe I am wrong but I thought these actually gave out negative ions. Why on earth would anyone want to reduce negative ions ? Negative ions actually aren't very negative as they actually make you feel better. After a large rain there is more negative ions in the air, which actually makes people feel happy.
Perhaps you mean negative energy and not negative ions. It is easy to get the two confused. Modern electronics can give out " dirty power " but that's not the same as negative ions.
Sorry I don't mean to be the grammar police or anything, and of course I could be wrong...I have made a mistake in the past, of course it's extremely rare