For those of you who are interested, FastFret is pure mineral oil.

When my dog was a puppy she raided my music bag, stole the FretFret tube and proceeded to open the container and chew the applicator into joyous splinters before I caught her. Since the container didn't have any info about the toxicity of the compound I called the company and asked if there was a material safety data sheet for the product (an OSHA requirement in most factories). The customer service rep spoke to the proper people, they found the sheet, and informed me that the lubricant was standard mineral oil, and therefore non-toxic to my puppy.