For easy reference, the NOP has published NOP 5611, National List Sunset Dates, a table of the sunset or expiration dates for all substances included on the National List of Allowed and Prohibited Substances (National List).

Under the Organic Foods Production Act of 1990, the National Organic Standards Board must review all substances on the National List every five years and recommend renewing, removing, or changing each listing. This process is commonly referred to as "sunset review." NOP 5611 is intended to provide the public an easy way to identify the sunset or expiration date for all substances included on the National List. It has been incorporated as part of the NOP Program Handbook.

The National List of Allowed and Prohibited Substances identifies substances that may and may not be used in organic crop and livestock production. It also lists the substances that may be used in or on processed organic products. In general, synthetic substances are prohibited unless specifically allowed and non-synthetic substances are allowed unless specifically prohibited. For example, a vaccine used to prevent pinkeye in livestock is an allowed synthetic substance while arsenic is an example of a prohibited natural substance. Some substances on the National List may only be used in specific situations, e.g. only for certain crops or up to a maximum amount. View National List. 

The NOP facilitates trade and ensures integrity of organic agricultural products by consistently implementing organic standards and enforcing compliance with the regulations throughout the world. Learn more.