The National List of Allowed and Prohibited Substances identifies the synthetic substances that may be used and the nonsynthetic (natural) substances that may not be used in organic crop and livestock production. It also identifies a limited number of non-organic substances that may be used in or on processed organic products.
In general, synthetic substances are prohibited for crop and livestock production unless specifically allowed and non-synthetic substances are allowed for crop and livestock production unless specifically prohibited.
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 the National List of Allowed and Prohibited Substances>
Changing the National List
Changes to the National List are initiated through a petition to add or remove a substance, or through the sunset review process. Anyone can submit a petition to amend the National List. The National Organic Standards Board (NOSB), a Federal Advisory Committee, reviews petitions and makes formal recommendations to USDA. The NOSB also reviews every substance on the National List every five years during the “sunset review” to confirm that the substance continues to meet required criteria.
Related Information
- List of Petitioned Substances: Access an alphabetical list of National List substances and substances that have been petitioned; some of these are also on the National List, but many are not. Substances may not be used in organic production or handling unless the substance has been added to the National List through a final rule.
- Learn more about Sunset Review
- National List Sunset Dates (pdf)
- How to Submit a Petition