The harm caused by plastic pollution is wide-ranging. It chokes wildlife above and below the waterline. An estimated one million sea birds and an unknown number of sea turtles die each year due to plastic debris clogging their digestive tracts, and marine animals of all sorts can become tangled and incapacitated by discarded fishing lines and plastic bags. Fish and other marine life ingest microplastics, which can find their way into the human food chain.