Illegal teeth whitening caused 'excruciating pain'

A number of beauticians in #London are performing illegal teeth-whitening procedures, which can leave patients in crippling pain if they go wrong.

One place was secretly filmed by BBC London using illegal levels of the hydrogen peroxide at a strength of 25%.

http://snip.ly/et84h#http://www.bbc.co.uk/news/uk-england-london-42906910