Not trying to hijack, just offering some info. Just because it's petroleum based does not mean that it is the only thing in there.
The MSDS lists " non hazardous materials" as less than 10 % of the content, I would venture a guess that herring oil would fall into this category. Check this site out and look in the sidebar entitled "scent secrets" they also talk about it.
http://www.outdoorcanada.ca/gear/recipe_success2.shtml