10. The scourge of plastic bags littering county roads. Besides being ugly, they may be deadly because they’re made with polyethelyne, a suspected human carcinogen. Plastics have found their way into the food chain. According to Maryland’s Department of Natural Resources, the bags don’t just kill sea life by being ingested. 100% of water samples from the Bay contain microplastics, and 94% of U.S. drinking water contains microfibers.