Registration Dossier

Administrative data

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Gene mutation has been investigated in bacteria using strains ofSalmonella typhimuriumandEscherichia coli, in accordance with OECD/EU test methods. Five tester strains TA1535, TA1537, TA98, TA100 and WP2uvrA were used and experiments were performed both in the absence and presence of metabolic activation, using liver S9 fraction from rats pre-treated with phenobarbitone and betanaphthoflavone. The substance, 1, 2, 3, 6 tetrahydrophthalic anhydride (THPA), did not induce reverse mutation in the tester strains, neither in the absence nor presence of S9 metabolism.


Tetrahydrophthalic anhydride (THPA) has been assayed for the ability to cause chromosomal damage in cultured human lymphocytes followingin vitrotreatment in the absence and presence of S9 metabolic activation. Methods used were in accordance with OECD/EU test methods. The substance does not induce chromosomal aberrations in human lymphocytes.


Tetrahydrophthalic anhydride was examined for mutagenic activity by assaying for the induction of 5trifluorothymidine resistant mutants in mouse lymphoma L5178Y cells afterin vitrotreatment using OECD/EU test methods. It was concluded that the substance does not induce mutation at the TK locus of L5178Y mouse lymphoma cellsin-vitro.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (negative)

Additional information

Justification for classification or non-classification

Non classification is justified based on negative findings in 3 separate and key in-vitro tests for gene mutation / mutagenicity.