Get to Know Your Spinach

A billboard promotes spinach in California, where the search for the origin of the E. coli outbreak is focused. (By Marcio Jose Sanchez -- Associated Press)

Suddenly, spinach is scary. Forget the payload of fiber, folate, calcium and iron this praiseworthy super-food delivers. The recent outbreak of a deadly strain of E. coli bacteria forced retailers to pull bagged spinach from their shelves.

Food dangers have always been with us. If your great-grandmother was careless when she canned the beans, she might have poisoned you with botulism. But these days a food scare makes the national news because its impact is national -- or global -- as food producers expand in size and food travels farther. In the current outbreak, at least 175 people in 25 states have been sickened.

In the United States, we generally assume our food is safe. But the tainted spinach has served to remind us just how disconnected most of us have become from our fruits and vegetables.

After almost a month of investigation, authorities have traced the contamination to farms in three California counties and to a processing plant in San Juan Bautista operated by Natural Selection Foods, a large producer of organic and non-organic greens in California, where about 75 percent of the nation's spinach is grown.

The possible causes in a case like this are many. Infection with E. coli comes from exposure to feces from the intestinal tract of mammals (such as cows, sheep, pigs, humans) borne by soil, water, tainted equipment or unwashed hands. In this case the transformation from good spinach to bad could have occurred at a number of points in the long trail from field to plate, and that's a good part of the problem right there -- a large company with a product sourced from many farms and handled by many workers, then shipped to many points of distribution.

Arun K . Bhunia, professor of food science at Purdue University, acknowledges that food-borne pathogens on fruits and vegetables have increased in recent years. This is partly because "much of it comes from countries outside the U.S. where quality is not assured properly," he says. But in this particular case, "large-scale distribution in multiple states really had a severe impact on the outbreak." Even the bags in which the product was sold contributed to the problem, acting as incubators for bacteria. These provide "the perfect environment in which to grow," Bhunia said. "As soon as the product is raised above refrigeration temperature, the bacteria start to grow and can multiply several-fold." He cites the consumer's demand for conveniently bagged produce as a factor in the rise of outbreaks.

A disaster like this is heartbreaking for both farmer and victim. It can happen on a small farm just as easily as a large one, and on organic or chemical farms alike if good husbandry is not observed. Water used to wash produce must be of drinking quality. Employees must wash hands before handling produce. Fresh manure should not be allowed to drift onto crops through wind, water runoff or irrigation. Fertilizing crops with manure is something farmers have done for thousands of years, and is an excellent practice if managed properly.

The manure used to fertilize fields -- or your vegetable garden -- can best be made safe by composting it (which heats it to a degree that kills pathogens) or by not applying it to any crop it will physically touch within 120 days of harvest. This is the standard enforced in organic agriculture -- although no such oversight is required on a non-organic farm -- and it is the standard that a home gardener should observe as well.

If the contamination had come from a small farm down the road from you, it would be a sad day for your community, but it would take much less time to track where the pathogen had come from and where it had traveled. The problem would be a painful, personal one, but it could be more speedily resolved. I once heard a German farmer describe how he felt about the members of his CSA (Community Supported Agriculture), a subscription-based farm where you purchase a share of the harvest in advance and then receive a weekly portion. There were several CSAs in his town (as there often are in the United States), and he felt honored that shoppers had chosen him as their professional grower and entrusted their families' health to him. Local residents can make such choices by observing which farmers are conscientious and run clean, well-managed operations.

Or they can grow their own food. Spinach, with a bit of protection, is a year-round crop, and if you have planted some for fall it is probably looking pretty good right now, as cool days favor its growth and sweeten its flavor. You will have the satisfaction of picking a bowlful for tonight's salad, a luxury that is priceless.