Must read: Brother of man hospitalized in Vegas says he believes man was sickened by ricin

SAN DIEGO - A man who has been hospitalized since Valentine's Day with respiratory ailments and failing kidneys told his brother he believes he was contaminated by the deadly ricin poison found in his Las Vegas motel room.

Roger Bergendorff regained consciousness on Wednesday and was upgraded to fair condition Monday at a Las Vegas medical center.

His younger brother, Erich Bergendorff, told The Associated Press that they spoke briefly on the telephone Sunday for the first time since the ricin was found, and said Roger claimed he had never had any intention of endangering anyone with the toxin.

'He did mention that he would have never done anything to anybody,' said Erich Bergendorff. 'He himself is under the impression he was contaminated by it - he did mention the ricin and seemed to say something like, 'Gee, it sure worked on me.'

Erich Bergendorff said his brother told him the ricin was easy to make. But he added that his brother, who was on a ventilator until last week, still had a hard time speaking clearly, so it was not clear whether Roger Bergendorff made it himself or watched someone else manufacture the powder.

'He did talk as though he just had it there, he was almost kind of casual about it,' said Erich Bergendorff, who talked to his brother on the phone from his home in Escondido, Calif., north of San Diego. 'It's almost as though in his own mind it wasn't that big of a deal.'

Roger Bergendorff, 57, was questioned by investigators from the FBI and the Las Vegas police on Friday in hopes that he could provide information about the Feb. 28 discovery of the ricin powder and castor beans, from which it is derived.

Officials from both agencies declined to comment about what they learned.

Doctors have not formally diagnosed Roger Bergendorff. Experts said his symptoms appeared consistent with ricin exposure, but the poison breaks down in the body within days, making it hard to trace.

Ricin can be lethal in amounts the size of the head of a pin. It has no antidote and is only legal for cancer research.

In court documents, police described the amount of ricin found in the vials as 'a large quantity' and characterized the poison as a 'biological weapon.' But officials have said they have not found evidence in the motel room or elsewhere of contamination and have downplayed the possibility that Bergendorff posed a threat.