Raw, fresh chili should be washed in clean water before used in cooking in order to remove any residual fungicides, sand and soil. Chili either fresh or powder form, can cause severe burning sensation to hands and may cause severe irritation to nasal passages, eyes and throat. Therefore, it may be advised in some sensitive individuals to use thin hand gloves and face masks while handling chilies.
Chili peppers contain chemical compound capsaicin. Capsaicin and its co-compounds used in the preparation of ointments, rubs and tinctures for their astringent, counter-irritant and analgesic properties.
Healthy, sane humans do not stab themselves in the thighs, or bathe their eyes in lemon juice. So why do we so love to assault one of the most sensitive organs in the human body, the tongue, with what amounts to chemical warfare? Chillies are unique among foods that we should otherwise not enjoy. For example, humans also have natural aversions to the bitterness of coffee or the harshness of tobacco, but those substances have some addictive qualities, which might make them desirable. Capsaicin, the compound that provides the mouth-watering punch of chillies, does not seem to have any addictive qualities whatsoever. And yet the preference for capsaicin is almost universal; nearly every culture has incorporated it into their cuisine in some way, for milllennia.