METHOTREXATE

Lapse in Appropriations

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Chemical Identification
CAS #	59-05-2
Formula	C₂₀H₂₂N₈O₅
Synonyms	amethopterin; 4-amino-l0-methylfolic acid; 1-glutamic acid, N-(4-(((2,4-diamino-6-pteridinyl)methyl)methylamino))benzoyl; glutamic acid, N-(p-(((2,4-diamino-6-pteridinyl)methyl)methylamino)benzoyl)-, L; methopterin; amethopterine; HDMTX; MTX; L-N-(p-(((2,4-diamino-6-pteridinyl)methyl)methylamino)benzoyl) glutamic acid

Physical Properties
Physical description	Bright yellow-orange, odorless, crystalline powder.
Boiling point		Molecular weight	454.46
Freezing point/melting point	356-399°F	Vapor pressure
Flash point		Vapor density
Specific gravity		Ionization potential
Lower explosive limit (LEL)		Upper explosive limit (UEL)
NFPA health rating		NFPA fire rating
NFPA reactivity rating		NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	M106
Sampling group
Sampler/Sampling media	OSHA versatile sampler (OVS-2) - 13 mm XAD-2 tube (270/140 mg) with GFF enclosed [SKC 226-30-16]
Sampling time^*	120 min
Sampling volume (TWA)^*	120 L
Sampling flow rate (TWA)^*	1 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	HPLC
Method reference	OSHA PV2146 (partially validated)
Notes
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		REL-TWA		TLV-TWA		PEL-TWA
PEL-STEL		REL-STEL		TLV-STEL		PEL-STEL
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	NA	Skin notation	NA	Skin notation	NA	Skin notation	NA
Notes: Not established		Notes: Not established		Notes: Not established		Notes: Not established
Health factors: See NIH-NLM PubChem.		IDLH
Carcinogenic classifications: IARC-3		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Methotrexate

NIOSH: Pocket Guide to Chemical Hazards - Methotrexate

Literature References

Bawle, E.V., Conard, J.V. and Weiss, L.: Adult and two children with fetal methotrexate syndrome. Teratology 57(2): 51-55, 1998.
Dastychová, E.: Allergic contact dermatitis in methotrexate manufacture. Contact Dermatitis 48(4): 226-227, 2003.
Deng, H., et al.: Investigating genetic damage in workers occupationally exposed to methotrexate using three genetic end-points. Mutagenesis 20(5): 351-357, 2005.
Izzedine, H., Launay-Vacher, V. Karie, S., Caramella, C., de Person, F. and Deray, G.: Is low-dose methotrexate nephrotoxic? Case report and review of the literature. Clin. Nephrol. 64(4): 315-319, 2005.
Kalantzis, A., Marshman, Z., Falconer, D.T., Morgan, P.R. and Odell E.W.: Oral effects of low-dose methotrexate treatment. Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod. 100(1): 52-62, 2005.
Lateef, O., Shakoor, N. and Balk, R.A.: Methotrexate pulmonary toxicity. Expert Opin. Drug Saf. 4(4): 723-730, 2005.
Pohanish, R.P. (editor): Methotrexate. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1504-1505.
Sessink, P.J., Friemel, N.S., Anzion, R.B. and Bos, R.P.: Biological and environmental monitoring of occupational exposure of pharmaceutical plant workers to methotrexate. Int. Arch. Occup. Environ. Health 65(6): 401-403, 1994.

Last Updated Date : 01/05/2021

Lapse in Appropriations

METHOTREXATE

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References