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Nomination Summary for Blue-green algae supplements (N20040)

Nominated Substances: Blue-green algae, Microcystin LR

Nomination Date: 09/00/2000

Nominator: NCI

Rationale: Blue-green algae supplements containing cyanobacteria are believed to be taken by over a million consumers. Measurable levels of microcystins, a potent hepatotoxin and suspected liver carcinogen, and anabaena, which contain possible neurotoxins, have been found in the supplements. It is suspected that some toxic metabolites found in cyanobacteria may be tumor promoters. Also, there is a lack of information re the chronic toxicity of cyanobacteria metabolites that are not acutely toxic.

NTP Principles: 2, 3, 5

Agents and Status

The following information relates to the specific agent and may include history from earlier or later nominations for this same agent.


Agent Name: Blue-green algae

CASRN: 101043-37-2

Agent Name: Microcystin LR