Grist: A deadly outbreak of E. coli in 2006, traced to a California spinach field, spurred an overhaul of food-safety regulations in the leafy-greens industry and thats got to be a good thing, right? Not so fast, says a study published last week in the journal Nature. Those regulations have contributed to a major loss of ecosystem diversity in Californias Salinas Valley, while at the same time doing little to alleviate the risk of food-borne illness. In an effort to reduce the potential for contamination,...