Species identification is critical because edible food-grade seaweeds (such as nori, wakame, and kombu) face FDA food safety requirements and must meet labeling standards, while industrial-grade algae destined for carrageenan or alginate extraction may be treated as raw material inputs with different compliance pathways. Certificates of species identity and processing method from the exporter help customs and FDA reviewers determine the correct regulatory treatment at entry.

Yes — seaweeds bioaccumulate iodine, arsenic, and heavy metals from their growing environment, and FDA has issued guidance on elevated inorganic arsenic levels in certain seaweed species. Importers of food-grade seaweed should request certificates of analysis covering heavy metals and iodine content from each production lot, and should verify that the exporting facility's food safety controls address marine environmental contamination. Admissibility and classification are complex; consult a licensed customs broker or FDA before importing.