You may seek to dazzle with your grin . . . but whitening your teeth could be putting you at risk.
Experts have discovered that 18 out of 20 whitening kits tested contain illegal levels of bleach.
One product they looked at contained 230 times the legal level of hydrogen peroxide, the common active ingredient.
The chemical, which can be used to dye hair blonde, could cause serious burning to the mouth.
The findings were revealed by the Trading Standards Institute yesterday at its annual conference.
Manufacturers and suppliers of those kits which did not meet the legal limit of 0.1 per cent for hydrogen peroxide, are being advised to withdraw them for sale and could face prosecution.
However, the unsafe brands have not been named.
Chief executive Ron Gainsford said: "Hydrogen peroxide is a chemical well known in the hairdressing industry, but it is also used in teeth whitening products to bleach teeth.
"Many people these days aspire to having the perfect Hollywood smile and some stars have paid a lot of money to achieve this through cosmetic dental treatment.
"There are much cheaper kits on sale for home use, for instance, some of those tested by Trading Standards cost as little as £14.
"But this could end up burning more than a hole in your pocket.
"We strongly recommend that anyone considering having their teeth whitened cosmetically should consult a qualified dentist."
In the last five years, the desire for cosmetic dentistry has increased.
But as well as causing chemical burns to the mouth, high levels of the bleach can aggravate gum disease and cause sensitive teeth.
Source - Daily Mail