Max Murison, a consultant plastic surgeon in South Wales, said that "we see people on a regular basis, probably monthly, where something terrible has gone wrong", as treatment has been done incorrectly, they have gone to someone not adequately trained, or tried to administer a product themselves.
He told our Correspondent Carl Edwards "these things can cause a lot of long-term harm, and we really need to protect the public."
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Aaron Ramsey has told his English team-mates at Arsenal to beware Wales overtaking them in the FIFA rankings.
Plenty of fine dry weather to come today and prolonged spells of sunshine. A cool easterly breeze will take the edge off the temperatures.
The three-day event in the Welsh capital is expected to attract more than 20,000 visitors.