The US Food and Drug Administration (FDA) sent a warning letter to a Nestle Purina PetCare manufacturing facility in Allentown, Pennsylvania, after an inspection in September 2014 revealed "significant deviations from the LACF (acidified and low-acid canned foods) regulations, Title 21, Code of Federal Regulations, Parts 108 and 113 (21 CFR Parts 108 and 113)."

Violations include:

• failure to process each low-acid canned food in conformity with at least the scheduled process filed with FDA
• failure to identify, from a processor chack or otherwise, deviations from the scheduled process of critical factors which are out of control and failure to record these deviations in a separate log
• failure to chlorinate or otherwise sanitize cooling water as necessary for cooling canals and recirculated water supplies
• failure to establish a system for product traffic control in the retort room to prevent un-retorted product from bypassing the retort process
• failure to install the mercury-in-glass thermometers in a location where they can be accurately and easily read
• failure to have records of all processing and production signed or initialed by a representative of plant management who is qualified by suitable training or experience

Keith Schopp, a spokesman for Nestle Purina, said the company is confident there are no food safety issues or risks to pet health with the company's products. Schopp said officials are in the process of providing FDA with measures it intends to take to correct the production errors.

The FDA said it requires a written response addressing the alleged violations, and that "failure to take appropriate corrective action may subject your firm and products to further actions, such as emergency permit control, injunction or seizure."