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Nomination Summary for 2,3-pentanedione (N20902)

Nominated Substances: 2,3-Pentanedione

Nomination Date: 04/18/2008

Nominator: NIEHS

Rationale: 2,3-pentanedione (acetylpropionyl) is a diketone utilized as a flavoring agent in diverse food products and is one of the few chemicals that imparts butter flavoring. Similar diketones used in butter flavoring include diacetyl and acetoin. Diacetyl has been implicated as the etiological agent in popcorn lung, a condition first observed in microwaveable popcorn factory workers. Occupational exposure to diacetyl occurs by the inhalation route. Popcorn lung is characterized by fibrotic lesions in the airways. Fibrotic lesions in the airways result in a respiratory disorder called obliterative bronchiolitis. Diacetyl may be removed from the butter flavoring mix used in the microwaveable popcorn industry. Potential flavoring substitutes include acetoin, a diacetyl trimer and 2,3-pentanedione. 2,3-Pentanedione is generally regarded as safe under Title 21, Volume 3, Part 172, Subpart F and Section 172.515 of the Code of Federal Regulations. Fully up to date toxicology information via the oral route is located in the Priority-based Assessment of Food Additives (PAFA) database under document number 1189. Little to no data exists concerning the toxicity of inhaled 2,3-pentanedione. Due to the structural and occupational exposure similarities to diacetyl, investigation of 2,3-pentanedione is warranted.

NTP Principles: not specified

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: 600-14-6

Agent Name: 2,3-Pentanedione