Advice on Wet Specimen Storage

I've worked in a vet clinic for over a year and everyone loves to take things home after surgeries, such as testicles or fetuses, and I recently heard that the specimens are not safe to store long term in formalin. Is this true? And if it is, what else could I transfer the specimen to after soaking in formalin?

​

For example, when my cat got neutered I was able to keep his testicles, which have been sitting in formalin for around four months. I have isopropyl alcohol that i can transfer things to, I'm just unsure of the process and if I need to clean it before transferring. Any advice would be great!!!