Is there any danger of preservatives in cosmetics?

A few days ago, 17 masks in Hong Kong were found to contain preservatives , and the preservative problem once again became the focus of attention. So, how does the preservative in cosmetics cause harm to the human body?
For cosmetics containing preservatives, Wang Wei, director of the dermatology department of the First Affiliated Hospital of Tsinghua University, said: "In fact, this is a common phenomenon. Cosmetics have various ingredients, each of which has various effects, such as whitening, In addition to keratin, skin rejuvenation, etc., including a variety of starch and gel, these ingredients contain protein, so the long-term quality of cosmetics must be added with a certain amount of preservatives, the only difference is the type and dosage.
Wang Wei further pointed out: "The cosmetics not only contain preservatives, but also various other additives, such as emulsifiers, forming agents, etc. The addition of additives can guarantee the texture of the cosmetics on the one hand, and the shape of the cosmetics on the other hand. If the forming agent is added, the related cosmetics can be formed into a "paste" shape, and if the water and oil are separated, the emulsifier can be added to the water and oil fusion. Of course, how to add and add these additives should be clearly defined by the state."
Preservatives will not harm the skin . Wang Wei explained: "From a medical point of view, there are two types of preservatives, one is harmful to the human body, such as industrial preservatives, even if it is extremely small. Can not be added; the other is a preservative that can be added, such preservatives include many different types, different types have different amounts when added, the Food and Drug Administration has related quantities and indicators It is stipulated that the addition of preservatives is safe within the scope of national laws and regulations."
From the influence of the chemical composition of preservatives, Wang Wei pointed out: "It may cause abnormal skin hyperplasia and cancer; chemical changes in related components under the irradiation of sunlight, making people sensitive to light, redness and blackening of skin , pain; cause allergies, red or oxygen symptoms; or cause skin burns. These adverse reactions are not necessarily present, if it is proportionally speaking, it is almost one in 100,000." Wang Wei also said: "General For example, if preservatives are added to the normal range, most people will have no problem."
Scientific response to preservatives Although some skin care products are packaged with “preservative-free”, the shelf life is 2 to 3 years, which seems to be somewhat contradictory. Guo Wenchao pointed out: "There is also a preservative in cosmetics. Consumers should treat it correctly. The use of preservatives in cosmetics can protect products and protect against microbial contamination. Although researchers continue to "preservative-free cosmetics" "Initiating challenges, but there are still difficulties in achieving and popularizing technology. Therefore, it is best for consumers to use cosmetics properly if they are unlikely to completely evade preservatives."
Adding a small amount of preservative to cosmetics that are generally certified for national safety does not cause excessive damage to the skin. However, there are still two precautions: First, use cosmetics as little as possible during sensitive periods of the skin, or use a single formula to reduce the irritation caused by preservatives. Second, some women like to mix and match cosmetics. Branded products, then the preservatives are mostly the same, which can reduce the stimulation caused by the combination of preservatives.