High temperature (400°F) pan liners have become extremely popular in foodservice due to the attributes of labor savings; improved food quality; and operational savings. PanSaver® (M&Q Packaging Corporation) first introduced the high temperature pan liners concept at the NRA Show in May of '98. The strength of the high temperature liner concept was so strong that PanSaver® soon had several competitors.
At this stage in the growth of the pan liner category there are no manufacturing regulatory requirements. Considering that pan liners are in direct contact with food at elevated temperatures, eventually there will be government regulations which ensure the quality (purity) of the liners. However, at this time there are no regulations. This places the responsibility of pan liner quality assurance on the end user.
It is easy to confirm that the liners you are using are of food grade resin and safe for direct food contact at elevated temperatures.
Be advised that "food grade" resin is much more expensive than "industrial grade" resin. If the manufacturer is not ISO 9002 System Certified (which requires stringent manufacturing practices, copious record keeping which traces all aspects of the origin of the product, and regular audits by a licensed authority), a resin substitution is possible. Direct food contact with an industrial grade (non-food grade) resin at elevated temperatures may release known carcinogens into the food. If there is an illness reported, for any reason, and an investigation pursues, only an ISO System Certified manufacturer can produce records which clearly show that the pan liner material is safe for direct food contact at elevated temperatures.
To confirm the pedigree of your liner, simply call your supplier and request a current copy of the manufacturer's ISO certificate.
Be safe and be certain that the pan liner that you buy is manufactured in an ISO System Certified environment.