Could the Spinach Scare Happen Again?

ALICE PARK

Investigators believe they've found the culprit behind the E. coli outbreak. But studies show that the bacteria can spread more easily than we thought.

A week after the first cases were called into the Centers for Disease Control (CDC), health officials have finally found what they believe could be the smoking gun in the 23-state outbreak of spinach-related E. coli poisoning. Until Wednesday, investigators at the CDC and the Food and Drug Administration (FDA) had only suspected that fresh, bagged spinach had caused nearly 150 people to fall ill, and led to one death, from the bacterial infection. Researchers had not been able to trace the bacteria to fresh spinach until they tested one of several opened bags of the leafy vegetable from the homes of sickened people. DNA fingerprinting confirmed not only the presence of E. coli, but also linked the bacteria found on the spinach to the same ones isolated from patients. This new information allowed health officials to trace the source of the outbreak to three produce-growing counties in California: Monterey, San Benito and Santa Clara.

Investigators still don't know how the greens became contaminated with E. coli 0157, but have descended on the Salinas Valley, which local farmers proudly call the Salad Bowl to the World. Because E. coli normally originates from the feces of people or animals, a team from the FDA are inspecting sanitation procedures used both in the fields and in processing plants, and looking into water-quality logs and even weather patterns, to determine if flooding or poor drainage caused contaminated runoff to bring the bacteria into contact with produce.

So far, flooding seems to be a reasonable explanation for the contamination, and earlier studies found that it doesn't take much to taint growing produce. In 2004, Michael Doyle, director of the Center for Food Safety at University of Georgia, documented how long E. coli 0157 remained on produce such as carrots and green onions when these vegetables were planted in composted manure that his team had intentionally contaminated with E. coli. "We found that you only have to apply contaminated irrigation water once, and the E. coli can still get into the soil and then contaminate that produce as it is growing," he says. Depending on how long the produce remained in the ground, says Doyle, the bug stuck to the food for as long as 140 days. That's well beyond the period at which it would be harvested — meaning that if the produce isn't treated and cleaned properly, the bacteria have a good chance of hitching a ride all the way to a salad plate.

Even more disturbing are recent studies showing that the bacteria may not be content to just live on the surface of produce, and may actually set up shop inside plant tissues, making them impossible to eliminate with a simple dousing in a chlorine bath, the current way that most fresh produce is cleaned. Eric Triplett, chair of microbiology and cell science at University of Florida, has published two studies documenting the ability of bacteria like salmonella to travel into a plant through its root system. "We just inoculate the roots and up they go, they fully colonize all over the plant," he told TIME.

If bacteria can routinely burrow into produce this way, that means that standards regulating ready-to-eat produce need to get even stricter. Potential sources of bacterial contamination, from animal droppings to improperly drained fields or unclean irrigation systems, should be monitored more tightly if the $2.6 billion prewashed salad industry is to survive. Already, some spinach farmers in California have plowed their spinach fields under, convinced that for the time being at least, no one will be eager to eat their greens.

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Today in history - Sept. 23

The Associated Press

Today is Saturday, Sept. 23, the 266th day of 2006. There are 99 days left in the year. Autumn arrives at 12:03 a.m. Eastern time.

Today's Highlight in History:

Two hundred years ago, on Sept. 23, 1806, the Lewis and Clark expedition returned to St. Louis more than two years after setting out for the Pacific Northwest.

On this date:

In 1642, Harvard College in Cambridge, Mass., held its first commencement.

In 1779, during the Revolutionary War, the American warship Bon Homme Richard, commanded by John Paul Jones, defeated the HMS Serapis.

In 1780, British spy John Andre was captured along with papers revealing Benedict Arnold's plot to surrender West Point to the British.

In 1846, Neptune was identified as a planet by German astronomer Johann Gottfried Galle.

In 1938, a time capsule, to be opened in the year 6939, was buried on the grounds of the World's Fair in New York City.

In 1939, Sigmund Freud, the founder of psychoanalysis, died in London.

In 1952, Republican vice presidential candidate Richard M. Nixon went on television to deliver what came to be known as the "Checkers" speech as he refuted allegations of improper campaign financing.

In 1957, nine black students who had entered Little Rock Central High School in Arkansas were forced to withdraw because of a white mob outside.

In 1962, New York's Philharmonic Hall (since renamed Avery Fisher Hall) formally opened as the first unit of the Lincoln Center for the Performing Arts.

In 1973, former Argentine president Juan Peron won a landslide election victory that returned him to power.

Ten years ago: Space shuttle Atlantis left Russia's orbiting Mir station with astronaut Shannon Lucid, who ended her six-month visit with tender goodbyes to her Russian colleagues. Ross Perot sued the bipartisan commission that voted to keep him out of the presidential debates, arguing that excluding him would deepen public cynicism and cause his campaign "incalculable damage."

Five years ago: President Bush returned the American flag to full staff at Camp David, symbolically ending a period of national mourning. Thousands gathered at New York's Yankee Stadium to offer prayers for the victims of terrorism; Mayor Rudolph Giuliani pledged that "our skyline will rise again." Thirteen coal miners were killed in an explosion at the Blue Creek Mine in Brookwood, Ala.

One year ago: Hurricane Rita, down to Category 3, steamed toward refinery towns along the Texas-Louisiana coast, creating havoc even before it arrived: Levee breaks caused new flooding in New Orleans, and 23 people were killed when a bus carrying nursing-home evacuees caught fire in Texas. Embattled FDA Commissioner Lester Crawford abruptly resigned. Puerto Rican nationalist Filiberto Ojeda Rios, wanted in a 1983 robbery of a Connecticut armored truck, died during a gunbattle with FBI agents.

Today's Birthdays: Actor Mickey Rooney is 86. Singer Julio Iglesias is 63. Actor Paul Petersen ("The Donna Reed Show") is 61. Actress-singer Mary Kay Place is 59. Rock star Bruce Springsteen is 57. Actor Jason Alexander is 47. Actor Chi McBride is 45. Actress Elizabeth Pena is 45. Country musician Don Herron (BR549) is 44. Actor Erik Todd Dellums is 42. Actress LisaRaye is 40. Singer Ani DiFranco is 36. Rock singer Sarah Bettens (K's Choice) is 34. Recording executive Jermaine Dupri is 34. Pop singer Erik-Michael Estrada ("Making the Band") is 27.

Thought for Today:

"I saw old Autumn in the misty morn

Stand shadowless like silence, listening

To silence."

• Thomas Hood, English author (1799-1845).

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