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Nomination Summary for Tryptophan microcontaminants (N97001)

Nominated Substances: 1,1-Ethylidenebis(tryptophan), 3-(Phenylamino)alanine

Nomination Date: 11/02/1996

Nominator: Private Individual

Rationale: Some people who used the dietary supplement L-tryptophan developed illnesses such as eosinophilia-myalgia syndrome (EMS). It was hypothesized that tryptophan microcontaminants such as 1, 1-ethylidenebis(tryptophan) (EBT) and 3-phenylamino) alanine (PAA) were responsible for the reported illnesses.

NTP Principles: not specified

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