Iowa is the country's leading producer of both pigs and corn. A very large percentage of that corn ends up inside the bellies of all those pigs where it ultimately becomes almost unimaginable amounts of manure that is then spread over all the cornfields generating more corn, more feed, more poop ad infinitum. Kind of a nice efficient closed loop system, except that all the manure spread on the fields (besides smelling seriously awful and sometimes makes the air unbreathable for miles around) contains very unhealthy levels of nitrate and potassium which sometimes causes cancer and birth defects. In fact, half of all Iowa waterways tested contain dangerous levels of these chemicals and the city of Des Moines needs to spend $10,000 a day filtering nitrates out of its water. Now that'a a really crappy situation!