An ionic air freshener is designed to remove dust and other pollutants from the air using a stream of negatively charged particles. These negative ions pass their charge onto pollutants in the air which are then attracted to a positively charged plate by magnetism. There is, however, some debate over whether an ionic air freshener is actually effective in cleaning the air, and some medical professionals are concerned that the machines emit ozone, which can be dangerous.
In 1978, researchers at the Swiss Meteorological Institute reported a correlation between seasonal winds and health conditions. They showed a link between seasonal winds in many regions and physical and mental conditions such as headache, depression and even heart attack. They also noted that these winds all came with a positive ionic charge. Air quality studies around waterfalls and after rain identified a negative ion charge and linked the negative charge to better air quality.
The ionic air freshener is built around this premise, generating a steady stream of negative ions into the air. As ions encounter particles floating in the air, such as dust, they pass on their negative charge. After being charged, the particles are attracted to positively charged molecules, forming clusters that become too heavy to float and fall out of the atmosphere. A positively charged plate is often installed on an ionic air freshener to attract pollutants like a magnet.
Manufacturers claim that the ionic air freshener can remove odors, dust, smoke, allergens and other irritants from the air. Some machines are equipped with a fan to circulate air and draw in pollutants, but they are otherwise silent. Advocates also point out that the ozone generated by an ionic air freshener acts as an oxidizer and germicide, making the air cleaner and safer to breathe.
Some experts have doubted the ability of the ionic air freshener to improve air quality, especially in models that are not equipped with fans. Without some mechanism for circulating the air, negative ions reach only a short distance from the machine. The air on the other side of the room might be entirely unaffected.
Even when circulation is not an issue, the charged plate does not effectively collect particles, some experts have said. As dust lands on the plate, negative and positive ions cancel each other out and sharply reduce the plate’s effectiveness. Charged particles are more likely to attach to walls or television screens until the charge dissipates, after which they are returned to the atmosphere.
Ozone is another source of concern. Although ozone is an excellent germicide, it also is dangerous to humans if concentrations get too high. An ionic air freshener produces only low levels of ozone, but in an enclosed space, levels of ozone can rise to dangerous levels.
