In a submission to MSPs meeting at the museum and gallery in Glasgow on Monday to hear an array of expert testimony, the Donor Watch group says "fidelity to donors' wishes is a precious matter".
Sir William Burrell, who gifted his collection to the city in 1944, stipulated the art should not be allowed to travel overseas. As a shipping magnate, he feared for the safety of his art while in transit.
Glasgow City Council, Glasgow Life, which runs the city's museums and galleries, and the Burrell Trustees believe air travel is safe enough to render Sir William's stipulations out of date, but have to pass the Burrell Collection (Lending and Borrowing) Bill through the Scottish Parliament to tour the treasures abroad.
The Burrell Collection building in Glasgow's Pollok Park is in need of a multimillion-pound revamp and will be closed from 2016 to 2020.
The committee will hear from Archie Graham, Glasgow City Council deputy leader, Dr Bridget McConnell, Glasgow Life chief executive and Sir Angus Grossart, Glasgow Life board member and chairman of Burrell Renaissance, at Pollok House on Monday.
Also speaking will be Jeremy Warren, collections and academic director of the Wallace Collection, Ben Thomson, chairman of the National Galleries of Scotland and Christopher McLaren, chairman of the Samuel Courtauld Trust.
Yesterday, it was revealed that, in a confidential submission, the director of the National Gallery in London, Dr Nicholas Penny, questioned the safety of transporting art overseas.
Dr Selby Whittingham, of Donor Watch, says in his submission: "There can be a case for departing from the terms of a bequest when those are incapable of being carried out wholly or safely ... but that does not apply in the Burrell case in this instance.
"This bill is a consequence of the current vogue for loan exhibitions and for using outward loans as barter for inward loans.
"This vogue is not wholly benign. It deprives visitors to a museum of works which they may expect to see. And we are not convinced that the transport of works of art is as free from hazard as the advocates of this measure optimistically maintain."
Dr Whittingham concedes it could be argued Sir William Burrell's conditions have already been broken "by the siting of the museum, and so it is no great thing to break another".
However, he adds: "To accept that is to abandon any pretence a donor's conditions are treated seriously. Perhaps the 'thin end of the wedge' argument is not always a compelling one, but it has proved to be an accurate prediction of future behaviour in [such] cases..."
In the meeting the committee will consider the general principles of the private bill at preliminary stage and decide whether it should proceed as a private bill.
In his submission to the Scottish Parliament committee considering the bill, Dr Penny said moving works of art has led to several major accidents, incidents and damage to works, many of which have not come to public attention.
He said he would be prepared to describe them in confidence to a "trustworthy individual nominated by Scottish Government" if the committee desired.
The director said he knew of 10 major accidents in transported art during his 27 years working in museums and galleries. The submission was removed from the Scottish Parliament's website on Thursday night. It was apparently posted in error, and the submission was meant to be confidential.