Beyond the mercury-based preservative thimerosal,  .  Thimerosal was taken out of childhood vaccines in the United States in 2001. Measles, mumps, and rubella (MMR) vaccines do not and never did contain thimerosal. Varicella (chickenpox), inactivated polio (IPV), and pneumococcal conjugate vaccines have also never contained thimerosal.  https://www.cdc.gov/vaccinesafety/concerns/thimerosal/index.html