2011-274. Request for Information on 2,3-Pentanedione and Other Alpha-Diketones Used As Diacetyl Substitutes

AGENCY:

National Institute for Occupational Safety and Health (NIOSH) of the Centers for Disease Control and Prevention (CDC), Department of Health and Human Services (HHS).

ACTION:

Notice of public comment period.

SUMMARY:

The National Institute for Occupational Safety and Health (NIOSH) of the Centers for Disease Control and Prevention (CDC) intends to evaluate the scientific data on 2,3-pentanedione (CAS #600-14-6, also known as pentane-2,3-dione; acetyl propionyl) and other alpha-diketones and develop appropriate communication documents, such as a Current Intelligence Bulletin, Criteria Document and/or other informational products, and potentially establish a Recommended Exposure Limit (REL) for diacetyl substitutes. NIOSH is requesting information on the following: (1) Published and unpublished reports and findings from in vitro and in vivo toxicity studies with 2,3-pentanedione, and other alpha diketones, (2) information on possible health effects observed in workers exposed to 2,3-pentanedione, and other alpha-diketones, (3) information on workplaces and products in which 2,3-pentanedione and other alpha-diketones can be found, (4) description of work tasks and scenarios with a potential for exposure to 2,3-pentanedione and other alpha-diketones, (5) workplace exposure data, and (6) information on control measures (e.g., engineering controls, work practices, personal protective equipment) that are being used in workplaces where potential exposures to 2,3-pentanedione and other alpha diketones occur.

Public Comment Period: Comments must be received by February 9, 2011.

ADDRESSES:

You may submit comments, identified by docket number NIOSH-189 by any of the following methods:

• Mail: NIOSH Docket Office, Robert A. Taft Laboratories, MS-C34, 4676 Columbia Parkway, Cincinnati, OH 45226.
• Facsimile: [phone].
• E-mail: [e-mail].

All information received in response to this notice will be available for public examination and copying at the NIOSH Docket Office, Room 111, 4676 Columbia Parkway, Cincinnati, Ohio 45226. A complete electronic docket containing all comments submitted will be available on the NIOSH Web page at http://www.cdc.gov/​niosh/​docket,, and comments will be available in writing by request. NIOSH includes all comments received without change in the docket, including any personal information provided.

FOR FURTHER INFORMATION CONTACT:

Lauralynn Taylor McKernan, NIOSH, Robert A Taft Laboratories, MS-C32, 4676 Columbia Parkway, Cincinnati, OH 45226, telephone: [phone] .

SUPPLEMENTARY INFORMATION:

2,3-pentanedione is an alpha-diketone that has received attention as a substitute for diacetyl. 2,3-pentanedione is structurally very similar to diacetyl since 2,3-pentanedione is a 5-carbon alpha-diketone and diacetyl is a 4-carbon alpha-diketone. Published reports on the toxicity of 2,3-pentanedione are currently only in abstract form but suggest that in rats 2,3-pentanedione causes airway epithelial damage similar to that produced by diacetyl (Hubbs et al. 2010b; Morgan et al. 2010). Preliminary data also suggest that, under certain conditions, both diacetyl and 2,3-pentanedione can cause changes in the central nervous system (Hubbs et al. 2010a). Additional alpha-diketones of interest include, but are not limited to, those used in food manufacturing such as 2,3-hexanedione and 2,3-heptanedione (Kreiss et al. 2010).

NIOSH seeks to obtain materials, including published and unpublished reports and research findings, to evaluate the possible health risks of occupational exposure to 2,3-pentanedione and other alpha-diketones used as diacetyl substitutes. Examples of requested information include, but are not limited to, the following:

(1) Identification of industries or occupations in which exposures to 2,3-pentanedione, and other alpha-diketones used as diacetyl substitutes may occur;

(2) Trends in the production and use of 2,3-pentanedione, and other alpha-diketones;

(3) Description of work tasks and scenarios with a potential for exposure to 2,3-pentanedione, and other alpha-diketones used as diacetyl substitutes;

(4) Workplace exposure measurement data in various types of industries and jobs where 2,3-pentanedione, and other alpha-diketones are used;

(5) Case reports or other health information demonstrating potential health effects in workers exposed to 2,3-pentanedione, and other alpha-diketones;

(6) Research findings from in vitro and in vivo toxicity studies;

(7) Information on control measures (e.g., engineering controls, work practices, personal protective equipment) being taken to minimize worker exposure to 2,3-pentanedione, and other alpha-diketones used as diacetyl substitutes;

(8) Educational materials for worker safety and training on the safe handling of 2,3-pentanedione and other alpha-diketones; and

(9) Data pertaining to the feasibility of establishing a REL for 2,3-pentanedione, and other alpha-diketones.

References

Hubbs, A. F., Cumpston, A., Goldsmith, W. T., Battelli, L. A., Kashon, M. L., Jackson, M. C., Frazer, D. G., Fedan, J. S., Goravanahally, M. P., and Sriram, K. (2010a). Acute central neurotoxicity of inhaled alpha-diketon butter flavoring compounds in the rat brain. Vet Path 47(6), 57S.

Hubbs, A. F., Moseley, A. E., Goldsmith, W. T., Jackson, M. C., Kashon, M. L., Battelli, L. A., Schwegler-Berry, D., Goravanahally, M. P., Frazer, D., Fedan, J. S., Kreiss, K., and Castranova, V. (2010b). Airway epithelial toxicity of the flavoring agent, 2,3-pentanedione. The Toxicologist: Supplement to Toxicological Sciences 114(1), 319.

Kreiss, K., Day, G. A., Cummings, K. J., and Kullman, G. (2010). Diacetul substitutes in bakery product manufacture Am J Respir Crit Care Med 181(1), A4650.

Morgan, D. L., Kirby, P. J., Price, H. C., Bosquet, R. W., Taylor, G. J., Gage, N., and Flake, G. P. (2010). Inhalation toxicity of acetyl proprionyl in rats and mice. The Toxicologist: Supplement to Toxicological Sciences 114(1), 316.

John Howard,

Director, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention.