Anti-nerve agent experiments were conducted on discarded tissue taken from patients without consent, an ex-public health boss has revealed.
Dr Gabriel Scally said Salisbury District Hospital had sold skin discarded after breast reduction surgery to Porton Down laboratory.
He said he put an end to the practice after discovering it 21 years ago.
The hospital said NHS common practice at the time was different to modern standards and consent is now given.
During the Cold War, Porton Down carried out tests on servicemen to determine the effects of nerve agents on human subjects
Most recently, the Ministry of Defence lab identified the nerve agent used in the Salisbury attacks.
Dr Scally, former head of Public Health England for the South West, said he made the discovery following a tip-off which led him to trawl hospitals to find out if human tissue had been retained without permission, and had now decided to go public with the details.
"I received a tip-off that tissue was being removed for purely clinical purposes, for surgical purposes from patients in Salisbury hospital and was being sold to the Ministry of Defence," he told BBC West health correspondent Matthew Hill.
"This was surplus skin removed in abdominal or breast reduction operations.
"I was told this was research of national importance into the protection against nerve agents.
"My reaction is, you still need permission from the patients. There may well be patients who may well have had an objection on ethical or moral grounds."
The spokeswoman for Salisbury NHS Foundation Trust said: "Until the Human Tissue Act came into force in 2004, there was a lack of clarity in the legislation and common practice in the NHS was different from modern standards.
"Between 1998 and 2003, Salisbury hospital acted in accordance with the recognised standards of the time."
The spokeswoman added that in 2007/8 it did send tissue samples obtained during abdominoplasty or breast surgery to Porton Down for research, but this was done so with patients' consent.
A spokeswoman for the Defence, Science and Technology Laboratory at Porton Down said: "We operate according to regulations laid out in the Human Tissues Act of 2004.
"Human tissue donation will not be undertaken without consent."
She added the lab's oldest records with Salisbury District Hospital dated back to 2003.