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Oh my goodness please no one take this seriously. Heating pennies will result in harmful zinc off-gassing. You do not want to breathe this in. Use dry beans for blind-baking. They are almost infinitely reusable with no harmful effects.
Using pennies has long been recommended by reputable cookbooks. Is there really a risk at 375 degrees F? I would think the everyday fumes from an unventilated gas oven are a much more significant problem, and that's fairly common in many parts of the US. Anyway, I've done it a hundred times, and my brain and lungs still work good-ish?
Good to know! I had never read that America's Test Kitchen actually recommended them. I heard pennies minted after 1982 had too thin a coating of copper and when scratched would release zinc. I guess you need much higher temperatures though. Ha! I've always just used a bag of dry black beans and recycled them for years.