Chemical Sampling Information
	Methacrylic acid
Quick Links General Description Exposure Limits Health Factors Monitoring Search    [use word(s)/phrase] Table of Contents By Name A B C D E F G H I J K L M N O P Q R S T U V W X Y Z By CAS Number General Description Synonyms: Methacrylic acid (glacial), Methacrylic acid (inhibited), alpha-Methacrylic acid, 2-Methylacrylic acid, 2-Methylpropenoic acid; 2-Methylene propionic acid OSHA IMIS Code Number: M339 Chemical Abstracts Service (CAS) Registry Number: 79-41-4 NIOSH, Registry of Toxic Effects (RTECS) Identification Number: OZ2975000 Department of Transportation Regulation Number (49 CFR 172.101) and Guide: 2531 153P (inhibited) [27 KB, PDF] NIOSH Pocket Guide to Chemical Hazards, Methacrylic acid: chemical description, physical properties, potentially hazardous incompatibilities, and more Exposure Limits American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): 20 ppm; 70 mg/m3 TWA National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): 20 ppm, 70 mg/m3 TWA; Skin Health Factors Potential symptoms: Irritation of eyes, skin, mucous membranes; eye, skin burns; cough, shortness of breath, labored breathing, pulmonary edema (may be delayed); skin blisters, loss of vision; INGES ACUTE: burning sensation; weakness; abdominal cramps, pain; SKIN ABS. Health Effects: Irritation-Eyes, Nose, Throat, Skin---Marked (HE14); Respiratory effects---pulmonary edema (HE11). Affected organs: Eyes, skin, respiratory system Notes: OSHA does not have a PEL for methacrylic acid. In 13-week inhalation studies with mice, the NOAEL of methacrylic acid was reported to be 352 mg/m3. Methacrylic acid is a substrate of the “valine pathway,” being metabolized to carbon dioxide and water via methylmalonyl-CoA and succinyl-CoA (substrates of the citric acid cycle). Although esters of methacrylic acid are skin sensitizers, contact dermatitis from methacrylic acid, itself, appears to be primarily due to a concentration-related irritation, ranging in intensity from mildly irritative to severely corrosive. Date Last Revised: 05/03/2007 Literature Basis: NIOSH Pocket Guide to Chemical Hazards: Methacrylic acid. International Chemical Safety Cards (WHO/IPCS/ILO): Methacrylic acid. Cosmetic Ingredient Review Expert Panel: Final report of the safety assessment of methacrylic acid. Int. J. Toxicol. 24(Suppl. 5): 33-51, 2005. Greim, H., et al.: Assessment of structurally related chemicals: toxicity and ecotoxicity of acrylic acid and acrylic acid alkyl esters (acrylates), methacrylic acid and methacrylic acid alkyl esters (methacrylates). Chemosphere 31(2): 2637-2659, 1995. Lazarov, A.: Sensitization to acrylates is a common adverse reaction to artificial fingernails. J. Eur. Acad. Dermatol. Venereol. 21(2): 169-174, 2007. Pohanish, R.P. (editor): Methacrylic Acid. In, Sittig’s Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1490-1491. Monitoring Methods used by OSHA Laboratory Sampling/Analytical Method: sampling media: Two Anasorb 708 Tubes in series analytical solvent: Methanol maximum volume: 24 Liters   maximum flow rate: 0.1 L/min current analytical method: High Performance Liquid Chromatography; HPLC/UV method reference: OSHA Analytical Method (OSHA PV2005) method classification: Partially Validated All Trademarks are the property of their respective owners. Accessibility Assistance: Contact the OSHA Directorate of Science, Technology and Medicine at 202-693-2300 for assistance accessing PDF materials.