Skin accounts for 7 percent of our body weight. It helps protect the body from external and internal threats and maintains bodily temperature. However, the epidermis and dermis are not known to be impermeable to chemicals. When toxic substances (irritants and allergens) permeate the skin layers, they result in skin inflammation. Skin hazard classification is critical in cosmetics as it helps to understand the impact of ingredients on people's everyday routines. This segment addresses irritative or allergic contact dermatitis, and how irritants can lead to inflammatory skin diseases. Contact dermatitis from photo irritants and photosensitivity are both light reactions, and they seem to occur when exposed to the resulting mixture of the chemical. It is thus crucial to perform research on these diseases and the effects of chemicals on the skin under sunlight (UV light) to safeguard human skin. Since almost all cosmetics are applied to the face and body, product safety is essential.

Index Terms: Skin, Cosmetic, Contact dermatitis, Disease