TPCH (Toxics in Packaging Cleaning House) was established in 1992, formerly known as CONEG (Coalition of Northeast Governors). TPCH is specifically responsible for promoting and coordinating the implementation of the Model Toxics in Packaging Legislation in the United States, a coordinated regulation aimed at reducing the content of certain harmful substances in packaging materials.

Due to the successful promotion of the TPCH bill, people often refer to the US regulations on the control of harmful substances in packaging materials as the TPCH packaging test (also known as the CONEG packaging test). Prior to this, 19 states in the United States had adopted this law. This regulation, which was implemented in 1989, mainly requires that heavy metals such as lead, cadmium, mercury, and hexavalent chromium will not be intentionally added to packaging or packaging components at any concentration, and the sum of the four heavy metal contents cannot exceed 100ppm when accidentally contained.

In February 2021, TPCH announced an update to the Packaging Toxic Substances Act. The updated content includes the addition of perfluoroalkyl and perfluoroalkyl substances (PFAS) and phthalates as categories of regulated chemicals, as well as new procedures and guidelines for identifying and controlling other chemicals of high concern in packaging.

Each state will increase the control of newly identified chemical substances based on its own situation, which will be officially implemented two years after its announcement.