Marina Kovalevskaya, 49, and her daughter, Yana Kovalevskaya, 26, were initially rushed to an emergency ward at the American Medical Center in Moscow and later transferred to the Sklifosovsky First Aid Institute.
A spokesman for the service declined to reveal any details saying that "the Moscow Department of Health has been working on the diagnosis."
But Lyubov Zhomova, a spokeswoman for the Moscow Department of Health, said in turn that "All information about their condition should be obtained via relatives or the U.S. Embassy in Moscow."
Thallium, a chemical used in rat poison and insecticides, has no smell, is tasteless and can be easily dissolved in water. As in the case of former Russian intelligence officer Alexander Litvinenko, who died last year in London, doctors presumed that he was poisoned with thallium. But later a closer medical examination revealed a large dose of polonium-210 in his body.
