People are rarely exposed to chemicals one at a time. PeopleImages/iStock via Getty Images Plus Imagine an ordinary Tuesday. You wash your hair, put on deodorant, drink coffee, pack lunch in a plastic container and commute through traffic to get to work. At work, the custodial staff wipes down a shared table with disinfectant. At home, you cook dinner, clean the kitchen and run the dishwasher. Each of these ordinary moments can involve exposure to chemicals. By itself, that is not a reason for c