An investigation into the chicken sold under Whole Foods’ private-label brand “365” has raised concerns about salmonella contamination linked to the products, according to a report by animal advocacy group Farm Forward. The findings suggest that much of the chicken sold at the upscale grocery chain originates from Perdue Farms processing plants, which also supply major retailers such as Walmart, Target, and Kroger.

The report, based on an analysis conducted the week of August 3, involved testing 247 raw chicken packages sourced from 30 Whole Foods locations across all six of the company’s sales regions. Farm Forward examined packages of breasts, thighs, and wings, identifying the processing facility via USDA federal codes. The group determined that 92% of the sampled chicken came from Perdue-operated plants.

Using USDA records, Farm Forward then assessed the presence and severity of salmonella contamination linked to those processing plants over the past year. The group found that 98% of the “365” brand chicken was processed at facilities with documented contamination by a highly virulent strain of salmonella.

Farm Forward’s executive director, Andrew deCorio-lis, stated that the group was initially unaware that Whole Foods sourced such a significant portion of its chicken from Perdue. The nonprofit, which aims to end factory farming, highlighted the disparity between Whole Foods’ marketing of its meat as antibiotic- and hormone-free and humanely raised, and the salmonella contamination risks identified.

Whole Foods describes its meat offerings on its website as meeting “rigorous standards” for humane animal treatment and being free of antibiotics and hormones. The company encourages customers to “feel good about the meat” they purchase.

Perdue Farms did not address the specific salmonella findings but noted it has practiced “No Antibiotics Ever” chicken raising methods for over a decade. Whole Foods did not respond to requests for comment regarding the report.

The investigation raises questions about food safety and transparency in poultry supply chains, particularly within private-label products marketed as premium by retailers like Whole Foods.