Anal bleaching is a very new and controversial area of cosmetic procedures, in which the dark skin around the anus is whitened or bleached to a much lighter shade in an attempt to increase the perceived attractiveness of the anus.
It is important to note that the anus is covered by very sensitive and delicate skin and mucosa, which are susceptible to a variety of irritant and allergic reactions to a wide range of chemicals.
Most skin bleaching creams and formulations contain potentially toxic or unsafe ingredients, which could sensitize or burn the anal skin and even be absorbed, albeit in small quantities, through the anal mucosa if it comes into contact with it.
The result of such contact could be severe discomfort, temporary burning, permanent scarring, hyperpigmentation of the anus, and anal incontinence due to burning of the anal sphincter fibers.
Spread of Infection
Another area in which chemical anal bleaching is potentially dangerous is its use in possibly unsterile environments, promoting the spread of the herpes virus or other infective agents.
Adverse Reactions to Specific Agents
Many bleaching creams contain hydroquinone, a potent bleaching agent, which is banned in many countries around the world, especially in European countries. It inhibits the enzyme tyrosinase, which is involved in a rate-limiting step of melanin production, and thus restricts skin coloration. It was de-recognized as generally safe for cosmetic use in 2006 by the US FDA, pending more detailed study on its adverse effects over both the short term and long term.
Hydroquinone is known to cause ochronosis, a skin condition in which the skin acquires a permanent bluish-black hue. It is also suspected to be carcinogenic. However, despite available evidence, its use has not yet been banned and many bleaching creams containing hydroquinone are still available for over-the-counter use.
Hydroquinone also results in thickening of collagen fibers in the perianal skin, causing it to appear rough or bumpy later on. Apart from chemical burns, hydroquinone results in photosensitization, increasing the susceptibility to sunburn. Moreover, should the area be exposed to ultraviolet rays later, this will cause an even darker color than before.
Arbutin is another ingredient used in skin lightening creams. Also known as bearberry, arbutin is touted as completely safe and natural, being obtained for medicinal use primarily from the leaves of Arctostaphylos uva-ursi. It is used both at home and in professional bleaching salons. However, it is converted to hydroxyquinone in the body and thus shares the dangers and toxicity of the latter.
Many bleaching preparations from outside the US contain mercury, an effective bleaching agent that also confers an extremely high risk of liver and kidney failure, cancer, and other symptoms of mercury poisoning.
Another ingredient used for skin bleaching or lightening is kojic acid. This is an organic acid derived from several fungi, especially Aspergillus oryzae, or koji. It is moderately effective in reducing tyrosinase activity, but is a much more potent skin sensitizer, provoking allergic reactions. It is also a category 2 carcinogen (may be carcinogenic, but without sufficient evidence to name it as a presumed or known human carcinogen) under the Globally Harmonized System of classification and labeling of chemicals.
Azelaic acid is yet another natural skin lightening product, often used along with aloe vera or ascorbic acid. It has a much milder action on skin color, yet may produce irritation and allergy in sensitive skin, resulting in symptoms of burning, itching, stinging, dryness or tenderness.
Laser or Cryogenic Bleaching
Laser or cryogenic anal bleaching can also lead to side effects, such as hyperpigmentation following the procedure, pain, scarring, and uneven loss of color.
Anal bleaching, like other skin bleaching procedures, is not a one-time event because melanin production will resume once the tyrosinase enzyme is regenerated. For this reason, chronic use of the bleaching chemicals is required, and the effects of cumulative exposure to this type of agent are not yet well understood in humans, though as mentioned above, several of them are carcinogenic in animals.