Empty old broken suitcases make for nice fort walls. Although not China, I remember a case of mercury poisoning several years ago, apparently the source was a skin whitening cream from Vietnam, and it actually killed a few people here. You're right, China is likely the biggest violator because they have all the chemicals there cheaply available.
I do enjoy people watching at airports, and because I am easily entertained, just like you I can have fun simply wandering around and looking for new chairs to sleep in or snacks to eat 😃.