When you put it on your skin, inorganic mercury comes with major risks, which, according to research from the World Health Organization, include kidney damage, skin rashes, skin discoloration, scarring, reduction in the skin’s resistance to bacterial and fungal infections, anxiety, depression, psychosis, and peripheral neuropathy (weakness, numbness, and pain in the hands and feet).
Vision problems and lung damage are also potential risks, according to the FDA. The way mercury exposure can cause vision loss — like peripheral vision loss — was explored in a 2014 study published in the journal Medical Science Monitor, which found chronic mercury exposure “has toxic effects on the retina [and] optical nerve neuronal fibers [which transmit visual messages from the eye to the brain].” Long-term use of skin-lightening creams that contain mercury is particularly dangerous, says Dr. Idriss. As mercury builds up in our system, it becomes harder to eliminate.
What steps are being taken to regulate mercury in skin-lightening creams?
The use of mercury in cosmetics is banned in many parts of the world, including throughout Europe and Africa, and is restricted in the United States. The World Health Organization lists mercury as one of the top 10 chemicals of major public health concern, along with arsenic, asbestos, and benzene.
There have even been multinational efforts to curb the use of mercury: In 2013, the Minamata Convention on Mercury, established by the United Nations Environment Programme, set an international limit on mercury in cosmetics of trace amounts of one part per million (ppm). As you probably deduced, it’s not just skin-lightening creams that can be contaminated with mercury; the convention noted that mercury can be found in other cosmetics such as eye makeup, eye-makeup remover, and topical antiseptics.
This is also the limit that the FDA adheres to: “Mercury compounds are allowed in cosmetics only as preservatives in eye-area products. They may be used only in a very small amount — the mercury must not be more than 65 parts per million (ppm) in the finished product — and only if no other effective and safe preservative is available. Mercury is not allowed in any other cosmetic products except in a trace amount of less than 1 ppm and only if its presence is unavoidable under good manufacturing practice.”
The Minamata Convention treaty, which was adopted by over 140 countries, went into effect in August 2017, though participating countries were given until 2020 to phase out the manufacture, import, and export of listed mercury-added products, including cosmetics.