Ruptured PIP breast implants should not cause any long-term health problems, experts have said.
Worried women who have been given the faulty implants will welcome the news that if the devices rupture they could cause irritation but will not have any significant lasting effects.
The NHS Medical Directors expert group said the gel materials used inside the implants are not toxic or carcinogenic.
Around 47,000 British women are believed to have been given the implants manufactured by French company Poly Implant Prothese (PIP). They were filled with non-medical grade silicone intended for use in mattresses and have been linked to rupture and swelling in the body.
But the experts warned that PIP implants are twice as likely to rupture as other brands. The group, led by NHS medical director Professor Sir Bruce Keogh, found that after 10 years the PIP implants have a 15% to 30% chance of rupturing. Other breast implant brands have a 10% to 14% rupture rate in the same timeframe.
The implants also contain the chemical compound siloxane, which is chemically similar to silicone and is found in many consumer products including hair and skin products and antiperspirants and deodorants.
But in the final report on the implants, the experts said the chemical does not present a health risk. They said that if a PIP implant does rupture, it has been found to cause local reactions in a small proportion of women, which can result in symptoms such as tenderness or swollen lymph glands.
Prof Keogh said: "This has been an incredibly worrying time for women. We have been determined to look thoroughly at all available evidence so we are able to give them the best clinical advice possible. Repeated tests on different batches of PIP implants have been carried out in the UK, France and Australia according to international standards. Those tests have shown that the implants are not toxic and therefore we do not believe they are a threat to the long-term health of women who have PIP implants.
"We have, however, found that these implants are substandard when compared to other implants, and that they are more likely to rupture. We would therefore advise that women who have symptoms of a rupture - for example tenderness, soreness or lumpiness - should speak to their surgeon or GP. I would ask all GPs to refer any patient who has concerns about their PIP implants to a specialist. I sincerely hope this helps to reassure women that their long- term health is not at risk."
The group, which studied information on 240,000 implants of differing brands that have been given to 130,000 women in England, also called for surgeons and clinics that have used PIP implants to contact their patients and share the latest information with them.