I have a BS in Criminal Justice with a Forensics Focus and a Minor in Chemistry.
I want to apply for an MS in Forensic Toxicology but am told that I would never get a job with a BS in Criminal Justice, even with the MS. Thus they wont admit me to the program.
I think this sounds short-sighted if employment is truly based on what my BS is in if I was able to complete the MS work with my background.
I've looked at employment ads and most of them do say, BS in physical or life science required but none of them say anything about the MS---I'm thinking of starting to call job posting to ask if I would be a candidate with the MS in Forensic Toxicology or Forensic Science and my BS in Criminal Justice.
I think you should call employers and see if they would accept a MS in Forensic Toxicology without a BS in life science or physical science. I don't think you will find any who will, but it would be worth the effort just in case some agency would.
I would expect that the real reason the college or university won't accept you into the Masters program is that you don't qualify for the program without a BS in physical or life science.
Most agencies require only a BS in life science or physical science (Biology is usually good) and not a MS degree. You may want to get a BS in biology instead of getting a MS. With the BS in life science or physical science you will qualify for most Forensic Science jobs.
My undergrad degree is in Political Science, my grad degree is an MFS. I had no problem finding job in the crime scene investigation field. I think you'll find the qualifications vary quite a bit based on the jurisdiction and location.