Richard Nixon exposed to radiation on Moscow trip in 1959, documents reveal

Richard Nixon and his wife, Pat, were exposed to potentially harmful radiation while staying at the US ambassador’s residence in Moscow in 1959, according to declassified Secret Service documents.

Nixon, who was vice-president at the time, was not informed of the threat, and the state department was only informed in 1976, when a member of his Secret Service detail, James Golden, revealed that detection equipment had measured significant levels of radiation in and around the Nixons’ sleeping quarters at the residence, Spaso House.

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Golden said he was later told by the state department that he had been exposed to “massive dosages” of ionising radiation produced by an atomic battery used by Soviet spies to power bugging devices hidden in the building. However, Golden had doubts about that explanation and it was not confirmed.

The incident was reported after Golden’s revelations in 1976, but this is the first time the underlying documentation has been made available online, after a request to the Nixon presidential library from the National Security Archive at George Washington University. One of the archive’s senior analysts, William Burr, who made the request, said “this unusual and virtually unknown cold war episode deserves more attention so the mysteries surrounding it can be resolved”.

The documents have been published as part of a series on the Soviet use of radiation of different kinds against US targets, including the exposure of the US embassy in Moscow to microwave radiation for many years. The records have fresh relevance in light of the current mystery surrounding Havana Syndrome, a cluster of mostly neurological symptoms suffered by scores of US diplomats and spies in recent years.

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Ionising radiation is defined as having sufficient energy to damage cells and alter DNA. The dosimeters in Spaso House during Nixon’s visit measured 15 roentgen per hour. That is short of a lethal dose, but the permissible standard for occupational exposure in the US at the time was just 5 roentgen per year.

After Secret Service agents denounced Soviet dirty tricks in earshot of the listening devices in the residence, the radiation stopped.

“We sat down on the beds facing each other and began berating the Russians in loud voices cursing them for pulling a trick like this and wondering in loud voices why they were taking us for fools and asking each other if they thought they were going to get away with doing this,” Golden testified.

Before his Moscow visit, Nixon was asked by another member of his Secret Service detail, John Sherwood, whether he wanted radiation detection devices taken on the trip. Sherwood pointed out that Soviet officials visiting the US had asked for Geiger counters. The vice-president turned down Geiger counters, but yes to more discreet dosimeters – though he said he would not wear one himself and did not want it known that the matter had been discussed.

On the first evening of the visit, on 23 July 1959, the dosimeter readings climbed rapidly, leading a senior military official in the entourage, Adm Hyman Rickover, an expert on nuclear naval propulsion, to suspect that there had been a nuclear accident. Rickover and the US ambassador, Llewellyn Thompson, agreed not to tell Nixon.

Golden was sceptical of the analysis by the state department’s medical division that the radiation came from atomic batteries used to power listening devices inside Spaso House. He pointed out that the radiation had stopped while he was in the building, so no one could have come in and removed the batteries. He concluded the state department experts were not being frank with him.