Methyltetrahydrophthalic anhydride

Agent Name
Methyltetrahydrophthalic anhydride
CAS Number
26590-20-5
Formula
C9-H10-O3
Major Category
Plastics & Rubber
Methyltetrahydrophthalic anhydride formula graphical representation
Synonyms
1,3-Isobenzofurandione, 3a,4,7,7a-tetrahydromethyl-; AC 220; AC 220J; Lindride; Methyl tetrahydrophthalic anhydride; 1,2,3,6-Tetrahydromethylphthalic anhydride; Phthalic anhydride, methyltetrahydro-; [ChemIDplus]
Category
Acid Anhydrides, Cyclic
Description
Liquid; [ICSC]
Sources/Uses
Exposures have been reported in workers applying polyester resin glues and curing epoxy and alkyl resins; [NIOSHTIC] Used as a hardener in epoxy resin systems; [ChemIDplus]
Comments
Occupational asthma reported in workers curing epoxy resins; [Malo] [Tarvainen K, et al. Immunologic contact urticaria due to airborne methylhexahydrophthalic and methyltetrahydrophthalic anhydrides. Contact Dermatitis. 1995 Apr;32(4):204-9.] Prolonged or repeated exposure may cause asthma and contact urticaria; [ICSC] Causes asthma, rhinitis, allergic conjunctivitis, and rarely, allergic urticaria; "A surface limit (TLV-SL) of 0.7 mg/100 cm2 is recommended to protect against induction of respiratory sensitization from skin contact with workplace surfaces." [ACGIH] See "ACID ANHYDRIDES."
Biomedical References

Exposure Assessment

TLV (ACGIH)
7E-05 ppm, (TLV-SL = 0.7 mg/100 cm2)
STEL (ACGIH)
0.0003 ppm, (TLV-SL = 0.7 mg/100 cm2)

Adverse Effects

Asthma
Yes

Diseases, Processes, and Activities Linked to This Agent

Diseases

Occupational diseases associated with exposure to this agent:

Processes

Industrial Processes with risk of exposure: