Lemon essential oil, Citrus limonium, possesses strong germicidal disinfectant properties, and it is a pleasant addition to formulations intended to purify the air. The astringency of lemon makes it useful for combating oily skin and hair. It can also help with bronchial problems and asthma, and it stimulates concentration. Products containing lemon essential oil help rid the air of second-hand smoke. Citrus oils may become cloudy when subjected to cold temperatures due to natural citrus wax present in the oil. Strong photosensitizer. Do not use within 4 hours of exposure to the sun.