The Washington state Department of Health announced a recall of Gibson Farms, Inc. bulk organic walnuts April 30.

They were joined by the U.S. Food and Drug Administration and the federal Centers for Disease Control and Prevention in advising people to stop eating organic walnut halves and pieces sold in bulk at several stores in Washington because of possible contamination with E. coli bacteria.

The Skagit Valley Food Co-op posted its own announcement on May 2. It does not use Gibson Farms walnuts in its deli or bakery foods.

The Department of Health reported at least 12 people in California...