LONDON/ROME A radioactive substance that killed former Russian spy Alexander Litvinenko has been found in Italian contact Mario Scaramella but so far he shows no sign of radiation poisoning, a British hospital said on Saturday.
However, an Italian senator who spoke to Scaramella on Saturday said health officials had told Scaramella the dose of radiation he has received is usually fatal.
Litvinenko's mysterious poisoning by the radioactive isotope polonium 210 has sparked a health scare and strained London's relations with Moscow.
In another twist, British health officials said on Saturday they had checked an area of top soccer club Arsenal's London stadium for radiation as part of the Litvinenko probe, but had found no risk to public health.
Litvinenko, a former agent turned fierce Kremlin critic, accused Russian President Vladimir Putin of ordering his slow, agonizing death.
Moscow denies involvement. Other theories have centered on the possible involvement of rogue Russian agents.
Scaramella met Litvinenko at a London sushi restaurant on November 1, the same day the Russian fell ill, to show him e-mails from a source warning both their lives might be in danger.
Officials said a female relative of Litvinenko -- reported to be his widow Marina -- had traces of polonium 210 in her urine. They said she was not in short-term danger and any long-term risk was likely to be small.
The London hospital treating Scaramella said he was well and initial tests showed no evidence of radiation sickness.
Italian Senator Paolo Guzzanti, who spoke to Scaramella by phone, said health officials had told him the amount of polonium in his body was 10 or 20 times less than that detected in Litvinenko, but was still in a lethal quantity.
"They also said so far, nobody could ever survive this poison, so it is very unlikely he could. But, if he doesn't collapse in three months, there is a kind of hope ... They said that every six months ... the radioactivity decreases by half," he told Reuters.
Italy's chief medical officer was briefed by health officials in London on Saturday, a British government source said.
The check on Arsenal's new 60,000 seat stadium is intriguing because Andrei Lugovoi, a former KGB officer who met Litvinenko on November 1, told British newspapers he traveled to London on October 31 with his wife and three children to watch CSKA Moscow play Arsenal in a Champions League game on November 1.
Lugovoi told The Times last week Litvinenko had asked to see him to discuss a business opportunity and said he had nothing to do with any attempt on Litvinenko's life.
An Arsenal spokeswoman said the club had been assured that the stadium was absolutely safe to operate.
British authorities said this week that traces of radiation had been found at 12 sites and aboard planes that carried 33,000 passengers in the past month.
"We know of nobody who has reported to any UK hospital with symptoms similar to Litvinenko," the government source said.
Tests for radiation at the university where Russian politician Yegor Gaidar collapsed last week and at the hospital that treated him proved negative, Irish health officials said.
Russia's Defense Minister Sergei Ivanov promised full cooperation with the Litvinenko investigation.
"I don't see any reason to speculate - like the Western press is actively doing right now - that these are the long arms of KGB or FSB (Russia's intelligence service) or that Litvinenko knew a lot as a prominent spy, which is totally wrong," he said in comments shown by Russia's state television Vesti-24 which said they were first broadcast by Al Jazeera.
About five Greeks who stayed at a London hotel visited by Litvinenko last month were being tested as a precaution, a Greek health official said.
Britain's Health Protection Agency gave the "all clear" to two EasyJet planes Scaramella flew on as well as three British Airways planes linked to the Litvinenko case.