Consumers are being warned to steer clear of skin lightening creams that can “act like paint stripper”.
Many contained the bleaching agent hydroquinone – the creams can also contain mercury.
The British Skin Foundation said people should speak to a doctor if they had any concerns about their skin.
The toxic products are being sold by rogue retailers, as well as online and at car boot sales and market stalls.
And they do not always spell out the correct levels of ingredients, putting consumers at risk.
Hydroquinone, described as “the biological equivalent of paint stripper”, can remove the top layer of skin, increasing the risk of skin cancer, and cause fatal liver and kidney damage. Mercury can cause similar life-threatening health problems.
Unless they are issued on prescription by a doctor, creams containing hydroquinone, steroids or mercury are banned in the UK – because of their potentially serious side-effects.