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General Description

  • Synonyms: Acetyl methyl carbinol; 1-Hydroxyethyl methyl ketone; gamma-Hydroxy-beta-oxobutane; 3-hydroxy-2-butanone; 2,3-butanolone; Dimethylketol
  • OSHA IMIS Code Number: A624
  • (IMIS Name History: Acetylmethycarbinol prior to 1/28/09)
  • Chemical Abstracts Service (CAS) Registry Number: 513-86-0
  • NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: EL8790000
  • Department of Transportation Regulation Number (49 CFR 172.101) and Emergency Response Guidebook: 2621 127
  • Chemical Description and Physical Properties:
    • light yellow liquid
    • molecular formula: C4H8O2
    • molecular weight: 88.10
    • boiling point: 148°C
    • melting point: 15°C
    • flash point: 50°C

Exposure Limits and Health Effects

Exposure Limit Limit Values HE Codes Health Factors and Target Organs
OSHA Permissible Exposure Limit (PEL) Not established    
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL) Not established    
American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) Not established    
CAL/OSHA PELs Not established    
  • National Toxicology Program (NTP) carcinogenic classification: Not listed
  • International Agency for Research on Cancer (IARC) carcinogenic classification: Not listed
  • U.S. Environmental Protection Agency (EPA) carcinogenic classification: Not listed
  • EPA Inhalation Reference Concentration (RfC): Not listed
  • Agency for Toxic Substances and Disease Registry (ATSDR) Inhalation Minimal Risk Level (MRL): Not established
  • NIOSH Immediately Dangerous to Life or Health (IDLH) concentration: Not established
  • Notes on Other Potential Health Effects and Hazards
    1. Occupational lung diseases have been reported in workers in the microwave popcorn production industry. Several volatile organic compounds, including acetoin, are released from the butter flavoring (NTP 2007).

Date Last Revised: 9/6/2012

Literature Basis

Monitoring Methods used by OSHA

Primary Laboratory Sampling/Analytical Method (SLC1):
  • Two specially dried Silica Gel Tubes in series. Each tube has a single 600-mg 20/40 mesh section and a glass-fiber filter, the filter faces forward when sampling. SKC 226-183, or equivalent. Use an opaque tube holder or wrap tubes with aluminum foil or other opaque material while sampling.
  • maximum volume: 9 liters
  • minimum flow rate: 0.05 L/min for long-term sampling; 3 liters at 0.2 L/min for short-term sampling.
  • note: Separate the two tubes and cap both ends of each tube as soon as possible after sampling. Individually seal the two tubes. Protect tubes from light after sampling.
  • current analytical method 1: Gas Chromatography; GC/ECD
  • analytical solvent: (95:5) ethanol:water with 2 mg/mL PFBHA reagent
  • method reference: OSHA Analytical Method (OSHA 1012)
  • method classification: Fully Validated
  • current analytical method 2: Gas Chromatography; GC/FID
  • analytical solvent: (95:5) ethanol:water
  • method reference: OSHA Analytical Method (OSHA 1013)
  • method classification: Fully Validated

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