4-poly(propyl), benzene sulfonic acid

Endpoint summary

Additional information

The genotoxic potential of the substance was investigated in fully compliant in vitro (gene mutation in bacterial cells and chromosome aberration assay) and in vivo (micronucleus) studies.

In the Ames test both Salmonella typhimurium and Escherichia coli strains were used. The test substance was tested up to the limit dose of 5000 µg/plate, a concentration at which precipitation occurred but not precluded the evaluation, both in the absence and the presence of metabolic activation. The results of the study were negative.

Similarly, in a chromosome aberration assay using cultured human peripheral blood lymphocytes performed up to concentrations causing reductions in the mitotic index and/or precipitation (i.e. 1^stexperiment: without metabolic activation the concentration of 432 µg/mL had a precipitate at the end of the treatment period and a 49% reduction in mitotic index; with metabolic activation the concentration of 432 µg/mL had a precipitate at the end of the treatment period and a 30% reduction in mitotic index; 2^ndexperiment: without metabolic activation the concentration of 203 µg/mL had a 54% reduction in mitotic index; with metabolic activation the concentration of 450 µg/mL had a precipitate at the end of the treatment period and a 51% reduction in mitotic index), results were negative.

In an in vivo micronucleus test, the substance was injected intraperitoneally to male mice, to allow maximal delivery to the test system, up to the dosage of 100 mg/kg bw that was considered to be the maximum tolerated dose (MTD) on the basis of a range-finding test. Hunched posture was noted in 1 and 2 of the 7 male mice treated at the MTD, 24 and 48 hrs following dosing, respectively. In addition, although not statistically significant, all treated groups had PCE/NCE ratios lower than their concurrent vehicle controls. These observations indicate that systemic absorption had occurred, and exposure of the target organ achieved. Under these conditions, the substance was negative for micronuclei formation.

Short description of key information:
The following information is available for the genetic toxicity endpoints:

Thompson P.W. (2007) AS305BD: Salmonella typhimurium and Escherichia coli/mammalian-microsome reverse mutation assay. Testing laboratory: Safepharm Laboratories Limited. Report no.: 0703-0380. Owner company: Chevron Energy Technology Company. Report date: 2007-10-08.

Murli H. (2007) Chromosomal Aberrations in Cultured Human Peripheral Blood Lymphocytes. Testing laboratory: Covance Laboratories Inc. Report no.: 6183-144. Owner company: Chevron Energy Technology Company. Report date: 2007-11-16.

Duward R. & Flanders L. (2007) AS305BD: Micronucleus test in the mouse. Testing laboratory: Safepharm Laboratories Limited. Report no.: 0703/0381. Owner company: Chevron Energy Technology Company. Report date: 2007-09-20.

These studies have been rated as 1 under the Klimisch scoring system and so are considered to be sufficient to address these endpoints.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

These studies form an adequate basis to conclude that the substance is not mutagenic.