The U.S. Department of Agriculture on Friday amended the Organic Foods Production Act, adding three substances to the National List of Allowed and Prohibited Substances as a tool for managing the substances used in organic production.

In general, natural substances are allowed in organics and synthetic substances are prohibited. The National List identifies the limited exceptions to these general rules and identifies nonagricultural and nonorganic agricultural substances or ingredients that may be used in organic handling.

The amendment allows the use of oxalic acid as a pesticide for apiculture, nonorganic pullulan for dietary supplements with “made with organic” claims and collagen gel as a casing for organic products such as sausages.