"It was later confirmed that such material had been taken from all 51 victims during post mortem examinations."
A report to be made public in the next few weeks will confirm that organs and tissue were taken without the permission of next-of-kin.
Fifty-one people lost their lives when the pleasure boat collided with the dredger Bowbelle on the River Thames on 20 August 1989.
Last year Deputy Prime Minister John Prescott ordered a public inquiry after relatives protested over the removal of 25 victims' hands at the time of the accident.
Second burials
During the inquiry, chaired by Lord Justice Clarke, it was revealed that the coroner, Dr Paul Knapman, had ordered the practice "for identification purposes".
Some families are now considering holding second funerals to reunite those who died with their hands and major organs.
Billy Gorman, who lost his sister-in-law Carmella Lennon-Gorman in the accident said: "My family would seriously consider taking legal action if we can against whichever hospital is involved - it's a violation of human rights".
Margaret Lockwood Croft, whose son Shaun, 26, died in the tragedy said: "We were informed that containers holding tissues or body parts of four of the victims had been found in the mortuary.
"It was later confirmed that such material had been taken from all 51 victims during post mortem examinations."
She added: "We want to know why these actions were taken when drowning was deemed the cause of death for all 51.
"This information is a further distressing note added to the burdens already borne by the families."
Two reports into the disaster are due to be made public within weeks.
Toxicology tests
One is a formal investigation into the collision, and the second is a non-statutory report into what happened to the bodies in the process of identification.
The bereaved were originally told that just blood and urine samples were taken for toxicology tests for drugs and alcohol.
Many of the victims of the Marchioness disaster were young men and women who had been celebrating a friend's birthday.
Earlier this year it was announced that RNLI lifeboats would take to the Thames for the first time, a move hailed by the families of Marchioness victims.