Here is google search link regarding Olfa mat odor:
https://www.google.com/#q=olfa+mat+odor&
I had purchased one of the little 5 x 8 mats and the smell was so awful I could not use it. I tried everything listed and even left it out on my back porch in the fresh air for over a year.....yes a year! It kinda became a mission lol. I bought all kinds of sprays that said it would remove any odor but not on this little mat It still had that smell. I finally trashed it as I didn't have a lot of money invested and decided I would never buy another olfa mat. I could not return it because it had been so long since I purchased it. My sister says my nose is too sensitive because I can't even get near the things in the stores.
So, if the smell doesn't go away in a very reasonable time, I would return it.
Good luck and hopefully your mat will be usable soon.