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Nordihydroguaiaretic Acid (NDGA) from Canada

NDGA is a potent antioxidant polyphenol from creosote bush used in food preservation and pharmaceuticals. HTS 2907.29.90.00 covers this tetraphenolic lignan as 'other' polyphenol. Synthetic versions also commercially available.

Duty Rate — Canada → United States

15.5%

Rate breakdown

9903.05.2910%Section 301 (forced labor) — additional 10% ad valorem on products of Canada

Import Tips

Include prior sanction letters for food additive use

Specify natural vs synthetic origin

Document peroxide value for antioxidant efficacy