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Nomination Summary for Artificial butter flavoring & constituents (N20704)

Nominated Substances: Acetoin, 2,3-Butanedione

Nomination Date: 07/16/2006

Nominator: United Food and Commercial Workers International Union

Rationale: Several outbreaks of fatal lung disease have been documented among workers exposed to the vapors of butter flavoring in the manufacture of popcorn, the most prominent chemical exposures being from diacetyl and acetonin. The potency and severity of diacetyl has been demonstrated by short term laboratory tests conducted by NIOSH.

NTP Principles: 1, 5, 7

Agents and Status

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

CASRN: 513-86-0

Agent Name: Acetoin

CASRN: 431-03-8

Agent Name: 2,3-Butanedione