sheltox doesnt work unless you direct spray on the Mr.Keong, basically sheltox is a layer of liquid that prevent the Mr from taking air, they do not have nose, they take air through their skin, so the sheltox doesnt kill it, it just die because of cannot take the o2. and sheltox is not harmful to human, unless u dont have a nose =P

stop eating in your car, remove all possible food for the Mr.Keong, ie newspaper, eventually they will die or leave your car.