Top 6 Myths: About Bottled Water
Do you wear a filter over your face when you walk outside? If not, why do think you need to spend significant amounts of money to install and regularly replace the filter in your car?
Yes, if you intake unfiltered external air through the grill you will suck in some really nasty air that contains toxic gases and particles from the area just above the road where exhaust pipes spout. But if you set your system to recycle, you are breathing the very same air that came from out front of your own house when you got in the car. Also, opening your windows is shown to significantly improve air quality because the highest concentration of toxic gases is right at exhaust pipe height, which is unfortunately nearly the same as intake grill height.
Finally, these filters effectively remove particles, but they are unable to do anything about the toxic pollutant gases which are very harmful. It is a false sense of security to waste your money on filters.
For certain individuals with medical conditions that make them highly sensitive to irritant particles, a HEPA filter used in conjunction with the recycle option on the system is your best bet. But for normal individuals, you might as well burn your money.