Last updated at 10:20 PM on 28th June 2011
Claims that the government is covering up 'clusters' of cancer among Transport Security Administration workers have sparked fears the agency's airport scanning machines could pose a risk to travellers.
The Electronic Privacy Information Center has gone on the attack against the TSA and the Department of Homeland Security after securing a selection of government emails in a Freedom of Information request.
Executive director Marc Rotenberg told media that documents show that the government 'has not been forthcoming with the public about the true extent of radiation risk with the airport body scanners.'
He claimed union representatives at Boston's Logan airport have already discovered a 'cluster' of cancer cases among TSA workers there.
He said the Department appears to have just 'dismissed' the concerns.
WHAT THE DOCUMENTS ARE SAID TO REVEAL
According to EPIC, the documents released on June 24 by its FOI request include agency emails, radiation studies, agreements concerning radiation testing programmes, and the results of some radiation tests.
EPIC says the records show that TSA employees have identified 'cancer clusters allegedly linked to radiation exposure while operating body scanners and other screening technology'.
It also claims the records show that the Department of Homeland Security has 'publicly mischaracterised the findings of the National Institute of Standards and Technology' over the devices.
DHS head Janet Napolitano claimed in a 2010 USAToday article that NIST 'affirmed the safety' of full body scanners.
According to the EPIC documents, NIST said in an email that it was concerned about the claim and that it did not test full body scanners for safety, nor does it do product testing.
The documents are also said to show NIST warning workers to avoid standing next to full body scanners.
And they cite a Johns Hopkins University study showing the radiation zones around the scanners could exceed safety limits.
However the TSA told 9NEWS NOW that it has implemented 'stringent safety protocols to ensure that technology used at airports to screen people and property is safe for all passengers, as well as the TSA workforce'.
The agency added: 'In addition to regular maintenance, each individual machine that uses X-ray technology is regularly tested to ensure the radiation emitted falls within the national safety standards.'
The agency claims it has the science to prove the machines are safe.
However scientists at the University of California have already written to President Barack Obama's science advisor to claim: 'There is still no rigorous, hard, data for the safety of X-ray airport passenger scams'.
They claim the agency is relying on tests performed by the machines' manufacturers.
EPIC also claimed that union representatives in Boston have cited a 'cancer cluster' among TSA workers there.
They have asked the agency to allow its members to wear radiation monitoring devices.
In 2010 EPIC filed a lawsuit to suspend the use of scanners at U.S. airports pending an independent review.
According to its website, EPIC, founded in 1994, is a 'public interest research centre in Washington, DC'.
The group was founded to 'focus public attention on emerging civil liberties issues and to protect privacy, the First Amendment, and constitutional values.'