While some of the victims told investigators that they had not eaten green onions , '' with green vegetables there is a possibility of cross-contamination from onions to other food substances in the production line , '' said Harry Duran , public health epidemiologist for Camden County , N.J. As the inquiry widened , federal and state officials were investigating two New Jersey suppliers to Taco Bell : McLane Foodservice , of Burlington , and Ready Pac Produce in Florence .