化妆品贮存时间过长或长期受日光照射,与空气接触发生过氧或自身氧化,使化妆品中的香精挥发、硬脂酸及水受杂菌侵蚀,膏体酸败,变色、变味、微生物繁殖,产生对人体有害的醛、酮之类化合物。所以,陈化、变质的化妆品不宜再继续使用。 护肤品,如雪花膏、香脂等,保质期一般为一年,超过这一期限极易变质。 Cosmetics storage time is too long or long-term exposure to sunlight, exposure to air over oxygen or its own oxidation, so that the volatile essence of cosmetics, stearic acid and water erosion by bacteria, paste rancidity, discoloration, odor, microbial proliferation, resulting Harmful to the human body aldehydes, ketones and other compounds. Therefore, the aging, deterioration of cosmetics should not continue to use. Skin care products, such as creams, balsams, etc. Shelf life is generally one year, exceeding the deadline can easily deteriorate.