An Italian restaurant in Mayfair is the latest location to be contaminated with the radioactive element that killed the Russian former spy Alexander Litvinenko.
The Health Protection Agency (HPA) said polonium-210 had been discovered at the Pescatori Restaurant in Dover Street.
Staff there are being offered urine tests to see if they have been contaminated.
The restaurant is believed to be among the locations visited by three Russian men who met Mr Litvinenko at the Millennium Hotel in Mayfair on the day he fell ill
The HPA said that remedial work had been carried out and the restaurant, a small family-run establishment specialising in seafood, was now open for business.
"As a result of a recent request from the Metropolitan Police, the Health Protection Agency has carried out monitoring of Pescatori Restaurant in Dover Street, Mayfair, which has been linked to the Litvinenko police investigation," the agency said.
"Some evidence of contamination with polonium 210 has been detected.
"Remediation measures have been carried out successfully at the restaurant, which is now open for business. On the basis of the monitoring results received there is no public health concern."
The HPA said it did not anticipate any significant health risk to staff or customers of the restaurant.
