California Growers Adjust Safety Practices After Last Year's Deadly E. Coli Outbreak

A group that oversees food safety programs for big California lettuce growers has changed its protocols in the wake of an E. coli outbreak last spring which caused five deaths and sickened more than 200 people across 36 states.  

The outbreak was linked to romaine lettuce grown in Yuma, Arizona. It was a deja vu moment for food safety specialists says Erin DiCaprio, a Food Virologist with the UC Davis Cooperative Extension.

“The romaine lettuce outbreak triggered some old memories of some past outbreaks,” says DiCaprio.

Notably, an E. coli outbreak in 2006 which was traced back to fresh spinach grown in California. In the wake of that case, the California Leafy Greens Marketing Agreement was formed as an industry-led effort to standardize food safety practices.

In the most recent outbreak, investigators with the U.S. Food and Drug Administration found that “the outbreak strain was present in some irrigation canals in close proximity to these farms,” explains DiCaprio. “It’s likely the E. coli in those irrigation canals came from a CAFO — or concentrated animal feed operation — that was adjacent to those canals."

Those findings have implications for California growers, who produce nearly three-quarters of the lettuce consumed in the U.S.

In response, California LGMA recently updated its food safety practices in several areas. Currently, leafy greens growers are already required to test their water on a monthly basis, according to Horsfall.

Going forward, "(growers) using surface water that is run adjacent one of these very large CAFOs, then they would also be required to treat their water with a disinfectant," says Horsfall.

When the winter lettuce planting season begins, growers will also need to triple the buffer zone between CAFOs and lettuce from 400 to 1,200 feet.

Patty Lovera with Washington, DC-based environmental group Food and Water Watch added a note of caution about how standards are set for buffer zones, water testing and water treatment.

"We just don't know what the right distance is,” she argues. “We don't know exactly how risky this contamination is. And so, a lot of what's happening is just trying to add margins of safety."

Lovera argues that more research is needed to understand what conditions create what risks.

As for the LGMA standards, they are not law; they are a “marketing agreement,” as Lovera points out.

“This is something that very large players in the industry do themselves," she says. "They come up with the standards and they enforce those standards. This is something the industry is doing to get out in front of this issue.”

Lovera says these food safety guidelines are in place in the absence of FDA rules on water testing requirements and other standards for the produce industry.