I always knew that Hydroquinone was not a positive addition to the skin care regime from my training many, many years ago. But now I am fascinated WHY hydroquinone is banned in some countries and other countries are fighting to have this added to the banned ingredients data base. I have been researching and reading through many scientific studies that have been published on this topic to learn more. Here is what I have found. What is Hydroquinone?
  • Available in 2% cosmetic formulations or 4% or more by prescription it does have potent antioxidant abilities.
  • Hydroquinone is used to lighten the dark patches of skin (also called hyperpigmentation, melasma, "liver spots," "age spots," freckles) caused by pregnancy, birth control pills, hormone medicine, or injury to the skin.
  • Hydroquinone does not bleach the skin but lightens it, and can only disrupt the synthesis and production of melanin hyperpigmentation.
  • It has been banned in some countries (e.g. France) because of fears of a cancer risk.
  • The European Union banned it from cosmetics in 2001, but it shows up in bootleg creams in the developing world.
  • It is sold in the United States as an over-the-counter drug, but with a concentration of hydroquinone not exceeding 2 percent.
  • Hydroquinone occurs in some plants as free hydroquinone or as arbutin (hydroquinoneβ-D-glucopyranoside) and therefore may be found in many consumer products, such as vegetables, fruits, grains, coffee, tea, beer, and wine. The concentration of hydroquinone may exceed 1% in some food preparations
What are the side effects of using Hydroquinone? 1. Skin Irritation: Studies involving larger groups generally note mild, transient adverse effects, usually in a fraction of subjects, that include erythema, skin peeling, burning sensation and irritant patch-test reactions  2. Contact Leukoderma/Vitiligo: skin whitening/losing its pigment. Vitiligo, or leukoderma, is a skin disease characterized by the loss of pigment due to the death or dysfunction of melanocytes. At least 5 cases of contact leukoderma have been reported in association with the use of hydroquinone-containing skin cream. The creams contained 2% or 3% hydroquinone. While the creams were being used for depigmentation to lighten areas of the skin, in these cases complete depigmentation, rather than lightening, was achieved in treated areas. The condition may lead to splotchy areas of depigmentation with confetti-like areas of hyperpigmentation (leukoderma-en-confetti). The condition is not an allergic response and is not detected by patch-tests.  3. Exogenous Ochronosis: Exogenous ochronosis is where your skin basically discolours a brown or blue/black colour due to topical exposure to various compounds, including hydroquinone. Because hydroquinone absorbs UV light in the “sunburn waveband” (peak at 293 nm), sunlight likely aggravates and accelerates exogenous ochronosis. Theories as to why this occurs is still being investigated. One theory is that the pigment cell (melanocyte) becomes resisitant to Hydroquinone and starts to over produce pigment. 4. Hydroquinone is Cytotoxic to our cells: and  has an effect on our cell differentiation and damages our DNA. Studies in rodents show "some evidence" that hydroquinone may act as a carcinogen or cancer-causing chemical, although its cancer-causing properties have yet to be proved in humans. 5. Hydroquinone passes through our urine and may affect our Renal Function. Hydroquinone is absorbed through the dermis and through the body and excreted through our urine. When Hydroquinone is metabolised it produces metabolites which has been proven to affect the health of our kidneys. One study showed that a 2% formulation average % absorbed was 57% with peak elimination from the body around 12 hours and full elimination by 5 days. Because hydroquinone has a high absorption rate in humans, additional studies to determine the safety of dermal use of products containing 2% hydroquinone are required. This is a topic I will keep an eye on, updating any new information from medical studies as they occur. Have a question about this topic? Or have a totally different question that you would like me to answer? Please email me here: sarah@skinmatrix.com.au Want advice with your Skin Care? Not sure which products are best for you? Complete our Matrix Program, an online skin care consultation for professional advice. Happy Skin Days, Sarah Wilkinson   References: http://ntp.niehs.nih.gov/ntp/noms/support_docs/hydroquinone_may2009.pdf http://en.wikipedia.org/wiki/Skin_whitening http://www.medicinenet.com/script/main/art.asp?articlekey=64167