For years, animal care records from UMass Chan Medical School in Worcester, Massachusetts show the same pattern: small animals left to suffer through incomplete or delayed euthanasia instead of a quick, painless death, as the law requires.

According to public records obtained by the animal rights group PETA, staff at the school have repeatedly failed the most basic promise a research lab makes to the animals in its care: a humane death. In 2018, two newborn mice were found thrown in the trash along with soiled bedding. In 2021, a hamster who was supposed to have been euthanized was found still in his cage next to two dead cage mates, a violation federal inspectors called serious enough to issue an Official Warning. Between 2023 and 2024, staff overfilled gas chambers with mice and dumped dozens of animals, including days-old babies, into a carcass freezer without ever checking whether they were dead. As recently as January 2026, months after UMass Chan adopted a "no-tolerance" euthanasia policy, an experimenter gassed mice and again skipped the physical check needed to confirm they weren't still alive.

"UMass Chan experimenters cannot even provide animals the final consolation of a humane death, instead stuffing them in freezers and trash cans while they're still alive," said Dr. Katherine Roe, PETA's chief scientist.

At least 121 animals have suffered through this pattern, and retraining and corrective plans haven't stopped it. The National Institutes of Health (NIH) shouldn't keep funding animal experiments at a school that can't guarantee animals even a merciful death. Its Office of Laboratory Animal Welfare should revoke UMass Chan's Public Health Service Assurance, the approval the school needs to receive federal funding for animal research, until it proves these animals are treated humanely.

Sign the petition to demand the NIH revoke UMass Chan's Public Health Service Assurance, before more animals are left to die slowly and alone.