Sign up for CNN’s Wonder Theory newsletter to uncover science news from across the cosmos. Get updates on breakthroughs, scientific feats, and much more. Facing a curious group of reporters, the inventor Thomas Midgley Jr. confidently poured a lead-infused substance over his hands while inhaling its fumes for nearly sixty seconds. “I could do this every day without any ill effects,” he proclaimed. It wasn’t long before Midgley himself sought medical care. But the broader impact of this