Plastics mimic estrogen?
You've probably heard of bisphenol A, more fondly known as BPA. It was first synthesized in 1891, and scientists in the 1930s developed it for use as a synthetic estrogen -- plastic bottles were the next step, obviously.
Just kidding. When BPA was replaced by a more effective synthetic estrogen, chemists went all mad scientist, mixed BPA with phosgene, a toxic gas used in WWI (yikes!), and voila: clear, shatter-resistant polycarbonate plastics were born.
BPA soon became a superstar of the plastic world, being used in everything from headlights, to water pipes, to canned food lining, to receipts, to your trusty unbreakable water bottle.