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Nomination Summary for Comfrey & its alkaloids (N98001)

Nominated Substances: Comfrey, Comfrey + Symphytine mixture, Symphytine

Nomination Date: 10/01/1997

Nominator: NIEHS

Rationale: The nomination of comfrey and symphytine by the NIEHS for testing is based on the potential for chronic human exposure and the limited amount of carcinogenicity data.

NTP Principles: 1, 2, 3, 5

More Detailed Information