Im going to use a scrap piece of 3/4" plywood that I had in the garage to cover the top of this cinder block smoker I built. I've tested in a couple times and the top temperature I've gotten is about 175F, which is what I want. Is using plywood like this going to cause me any problems with chemicals leaching out? Or does plywood leach chemicals at 175F? Here's a photo of my smoker without the plywood top. Video coming soon.