OXALIC ACID | Occupational Safety and Health Administration

OXALIC ACID†

Chemical Identification
CAS #	144-62-7
Formula	C₂H₂O₄
Synonyms	ethanedioic acid; oxalic acid (aqueous); oxalic acid dihydrate

Physical Properties
Physical description	Colorless, odorless powder or granular solid.
Boiling point	sublimes	Molecular weight	90.04
Freezing point/melting point	372°F	Vapor pressure	<0.001 mmHg
Flash point		Vapor density	4.3
Specific gravity	1.90	Ionization potential
Lower explosive limit (LEL)		Upper explosive limit (UEL)
NFPA health rating	3	NFPA fire rating	1
NFPA reactivity rating	0	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1970
Sampling group
Sampler/Sampling media	GFF (37 mm), Type A/B [SKC 225-701]
Sampling time^*	100 min
Sampling volume (TWA)^*	100 L
Sampling flow rate (TWA)^*	1 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	IC
Method reference	OSHA PV2115 (partially validated)
Notes	Sample open-faced!!
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device
Model/Type
Sampling information (see manufacturer instructions)

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	1 mg/m³	REL-TWA	1 mg/m³	TLV-TWA	1 mg/m³ [2014]	PEL-TWA	1 mg/m³
PEL-STEL		REL-STEL	2 mg/m³	TLV-STEL	2 mg/m³ [2014]	PEL-STEL	2 mg/m³
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	N	Skin notation	N	Skin notation	N	Skin notation	N
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes:		Notes:		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	500 mg/m³
Carcinogenic classifications: Not listed		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Oxalic acid

NIOSH: Pocket Guide to Chemical Hazards - Oxalic acid

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Oxalic acid, anhydrous [144-62-7] and dihydrate [6153-56-6]. See annual publication for most recent information.
Chen, C.L., Chou, K.J., Wang, J.S., Yeh, J.H., Fang, H.C. and Chung, H.M.: Neurotoxic effects of carambola in rats: the role of oxalate. J. Formos. Med. Assoc. 101 (5): 337-441, 2002.
Pohanish, R.P. (editor): Oxalic 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. 1763-1765.
Rofe, A.M., James, H.M., Bais, R., Edwards, J.B. and Conyers, R.A.: The production of (14C) oxalate during the metabolism of (14C) carbohydrates in isolated rat hepatocytes. Aust. J. Exp. Biol. Med. Sci. 58 (2): 103-116, 1980.
Salinas, M.L., Ogura, T. and Soffchi, L.: Irritant contact dermatitis caused by needle-like calcium oxalate crystals, raphides, in Agave tequilana among workers in tequila distilleries and agave plantations. Contact Dermatitis 44(2): 94-96, 2001.
Tse, K.C., et al.: Star fruit intoxication in uraemic patients: case series and review of the literature. Intern. Med. J. 33 (7): 314-316, 2003.

Last Updated Date : 01/28/2021

OXALIC ACID†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References