(NAFB.com) – The nonprofit group Farm Forward joined a consumer class-action lawsuit against Whole Foods alleging that the retail giant is deceiving shoppers about beef products in its stores. Since 1981, Whole Foods has claimed that all of the animals within its supply chain are raised without antibiotics. However, an independent laboratory found antibiotic residue in “antibiotic-free” meat bought from a Whole Foods store in California. Antibiotic-free meat can cost as much as 20 percent or more than conventional meat, and surveys show 75 percent of consumers are willing to pay more for it. In April, Farm Forward released results of a program that tested Whole Foods meat for antibiotic residues. Among the findings, Farm Forward found residue of an antibiotic that can be used to promote growth in cattle in a meat product labeled “organic” and “antibiotic free.” Farm Forward says it has proof of deceptive marketing practices by Whole Foods.