Sales of silicone implants made by Brazil's Silimed and used in thousands of patients in Britain have been suspended due to safety concerns, British medical regulators and suppliers said on Thursday.

The Medicines and Healthcare Products Regulatory Agency (MHRA) said it and other European regulators are testing Silimed's products - which include breast, penile and testicular implants - after contamination was detected during an audit of the company's manufacturing practices.

A German authority appointed to monitor Silimed "has recently carried out an inspection of the manufacturing plant in Brazil and established that the surfaces of some devices were contaminated with particles," it said in a statement.

The Silimed suspension covers devices used in plastic surgery such as breast and pectoral implants, urological devices including testicular and penile implants and vaginal stents, as well as other surgical devices, the MHRA said.

Eurosurgical, a company which distributes Silimed's products in Britain, said it had supplied around 13,000 implants in the UK over the past five years.

"The vast majority would have been breast implants, and around 60 percent of those would have been for use in cosmetic breast enlargement," Eurosurgical's Managing Director Peter Cranstone told Reuters.

A spokesman for the MHRA said it did not yet know whether any potentially contaminated products would have reached patients, and did not know how many Silimed products might be affected. "All those questions are part of our current investigations," he said.

The MHRA statement said, however, that "for the moment there has been no indication that these issues would pose a threat to the implanted person's safety."

"EU health regulators have initiated testing of samples of products to establish if there are any health risks," it said.

Silimed, which says on its website it is the third largest implant maker in the world, said in an email to Reuters it was preparing a technical note to show its products comply with national and international standards, and will send it to European health authorities.

The Silimed product suspension comes after medical authorities found in 2010 that one of the world's leading breast implant makers, France's Poly Implant Prothèse (PIP), was not using medical-grade silicone in its devices, leading them to have double the rupture rate of other implants.

Hundreds of thousands of patients across Europe and South America were affected, and PIP's president, Jean-Claude Mas, was given a four-year jail sentence in December 2013.

The British Association of Plastic, Reconstructive and Aesthetic Surgeons (BAPRAS) said it was aware of the Silimed issue and was working closely with British regulators.

"There has been no indication...that these issues pose a threat to patient safety, however we are advising our members to contact any patients who may be affected," BAPRAS president Nigel Mercer said in a statement.

He said any patients with concerns about implants should seek advice from their surgeon or clinic.