E. coli is found only in the intestines of cows, birds, pigs, and other warm-blooded animals. Society's dependence on meat and dairy products means that millions of cows must be intensively raised in animal factories. Under such crowded conditions, it is easy for E. coli bacteria to spread from cow to cow. In fact, most of the 10 billion cows, pigs, and birds butchered every year in this country are covered with E. coli bacteria (though not necessarily the 0157 variety), an indicator of fecal contamination.
Plant-based foods, on the other hand, don't normally harbor E. coli or other fecal bacteria. When fruits or vegetables do contain E. coli, it is because animal manure was used to fertilize crops or has leaked into waterways. Cross-contamination can also occur when fruits and vegetables are placed on the same surface as meat.
According to The Los Angeles Times, investigators have traced the tainted spinach to California's Central Coast, and suspect that waste runoff from nearby livestock operations is responsible for the bacterial contamination.
Shocking as this is, it's no big surprise. The Environmental Protection Agency has reported that livestock operations pollute our waterways more than all other industrial sources combined. Animals raised for food produce approximately 130 times as much excrement as the entire human population-an astounding 87,000 pounds per second. The waste often seeps into our waterways, killing marine life and sickening people.
It only takes a few bacteria to make people sick: Scientist Guy Plunkett of the University of Wisconsin-Madison, where the genetic code of E. coli was mapped, reports that as few as 10 to 100 E. coli bacteria are sufficient to infect a human. According to The Los Angeles Times, a single cow can shed as much as 100 billion fecal bacteria a day.