mash tun - are all coolers the same type of plastic?

Basically, are square and round coolers made out of the same type of plastic? I have opened a couple of non-rounds that seemed to have a chemical "plastic" odor to them. Am I over thinking this?

Side rant- I went to buy a home depot round cooler and the help couldn't find the 3 that were somewhere in the store in an hour I know its out of season, but come on

I don't have a answer for you but I would also like to know.

I know that some of them have Micro-ban infused in the plastic, I don't want that in my beer!

I use a round beverage cooler. It's made to hold and serve liquid from and the inside is pretty hard plastic. Other coolers are made to hold ice and food or canned drinks, so the plastic walls never touch the food. My rectangular cooler def has softer plastic inside. Just some observations but this is one of the reasons I went with the Bev cooler. Plus, easier to stir. Who uses a rectangle or square pot? J

After tour first mash it will smell like grain, don't worry about the smell. Rinse it with pbw first and you should be good to go.

Don't think they're all the same. I suggest using only those made of HDPE 2.