Skin whitening cells causes the skin to naturally regenerate itself. Excess melanin comes to the surface and peels off in a few days. This is particularly useful in sensitive areas like the genitals where laser treatment could leave a scar. Efficacy of the treatment depends on the depth of the pigment. There is evidence to suggest that some types of skin-whitening products use active ingredients, such as mercurous chloride and hydroquinone, which can be harmful. Hydroquinone is not available without a prescription in Europe. It is only available when prescribed by a medical doctor (e.g. a general practitioner). This is also the
White (horse) as described below, can act to produce off-white phenotypes. Horses with strongly diluted coat colors usually have pale blue eyes, cream-colored coats, and rosy-pink skin. White markings are usually visible upon closer inspection. Although white horses are sometimes called "albino" there are no reported cases of a true "albino" horse. There are also references in literature calling white horses "albino". Dominant white in horses is caused by the absence of pigment cells (melanocytes), whereas albino animals have a normal distribution of melanocytes. In other animals, patches of unpigmented skin, hair, or eyes due to the lack of pigment cells (melanocytes)