OSWIECIM, Poland - In a modern conservation laboratory on the grounds of the former Auschwitz camp, a man wearing blue rubber gloves uses a scalpel to scrape away rust from the eyelets of small brown shoes worn by children before they were murdered in gas chambers.

Colleagues at the other end of a long work table rub away dust and grime, using soft cloths and careful circular motions on the leather of the fragile objects. The shoes are then scanned and photographed in a neighboring room and cataloged in a database.

The work is part of a two-year effort launched last month to preserve 8,000 children’s shoes at the former concentration and extermination camp where German forces murdered 1.1 million people during World War II. Most of the victims were Jews killed in dictator Adolf Hitler’s attempt to exterminate the Jews of Europe.

The site was located during the war in a part of Poland occupied by German forces and annexed to the German Reich. Today it is a memorial and museum managed by the Polish state, to whom the solemn responsibility has fallen to preserve the evidence of the site, where Poles were also among the victims. The Germans destroyed evidence of their atrocities at Treblinka and other camps, but they failed to do so entirely at the enormous site of Auschwitz as they fled the approaching Soviet forces in chaos toward the war’s end.

Eight decades later, some evidence is fading away under the pressures of time and mass tourism. Hair sheared from victims to make cloth is considered a sacred human remain which cannot be photographed and is not subjected to conservation efforts. It is turning to dust.

But more than 100,000 shoes of victims remain, some 80,000 of them in huge heaps on display in a room where visitors file by daily. Many are warped, their original colors fading, shoe laces disintegrated, yet they endure as testaments of lives brutally cut short.

The tiny shoes and slippers are especially heart-rending.

“Children’s shoes are the most moving object for me because there is no greater tragedy than the tragedy of children,” said Miroslaw Maciaszczyk, a conservation specialist from the museum’s conservation laboratories.

“A shoe is an object closely related to a person, to a child. It is a trace, sometimes it’s the only trace left of the child.”

Maciaszczyk said that he and the other conservation workers never lose sight of the human tragedy behind the shoes, even as they focus on the technical aspects of their conservation work. Sometimes they are overcome by emotion and need breaks. Volunteers working with adult shoes in the past have asked for new assignments.