Phthalimide

Endpoint summary

Additional information

Phthalimide is not active in a variety of mutagenicity tests in vitro. It is not mutagenic in bacterial reverse mutation test (OECD TG 471 and 472) in the presence and absence of metabolic activation system (S9-mix). It does not induce mutations in the mouse lymphoma assay. In the chromosomal aberration test (OECD TG 473) no polyploidy is observed at any concentration in the absence and presence of metabolic activation. Weak clastogenic effects are observed in the presence of metabolic activation at high concentrations where cytotoxicity is seen in parallel. Genotoxicity studies in vivo are not available. Overall phthalimide is considered to be not genotoxic in vitro and based on the available data it is anticipated that it will not be genotoxic in vivo.

Short description of key information:
OECD SIDS
Studies in Animals
In vitro Studies
Phthalimide was not mutagenic in bacterial reverse mutation tests (OECD TG 471 and 472) in the absence or presence of metabolic activation in different Salmonella typhimurium and Escherichia coli strains at doses of up to 5000 µg per plate by the pre-incubation or plating method (Bayer AG, 1993; MHW Japan, 1999).
In a chromosomal aberration test (OECD TG 473) no polyploidy or clastogenicity was observed in the absence of metabolic activation in Chinese hamster CHL/IU cells. Slight induction of structural chromosome aberrations was observed in the presence of metabolic activation at the 2500 µg/ml dose, and this observation became statistically significant at 5000 µg/ml. This weak induction was observed only at high concentrations where cytotoxicity was seen in parallel (50% growth inhibition concentration with S9-mix 4524 µg/mL) (MHW Japan, 1999). In view that the observed effects just meets the investigator´s criterion for a positive response (>= 10%) and the effects were seen only at high, cytotoxic concentrations the relevance of these observations appears to be rather limited. Consequently, phthalimide was considered to be not clastogenic (MHW Japan, 1999).
Positive and negative controls gave the expected results in all in vitro Studies reported.
In vivo Studies
No data on in vivo mutagenicity are available

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Based on the available data there is no reason for classification.