3-dimethylaminopropan-1-ol

Endpoint summary

Additional information

Dimethylaminopropanol was tested in the Ames reverse mutation assay (GLP compliant study according to OECD guideline 471 and 472) using Salmonella typhimurium strains TA98, TA100, TA1535 and TA1537 and Escherichia coli WP2 uvr A at 20 to 5000 µg/plate (standard plate and preincubation test) with and without metabolic activation. Dimethylaminopropanol was slightly cytotoxic at the highest concentration in all 4 strains of S. typhimurium and in E.coli WP2 uvr A. Under the conditions tested, dimethylaminopropanol was not mutagenic in any of the S. typhimurium strains and E.coli WP2 uvr A.

HPRT assay:

In a GLP-compliant study performed according to OECD guideline 476, the potential of 3-Dimethylaminopropan-1-ol to induce gene mutations at the hypoxanthine-guanine phosphoribosyl transferase (HPRT) locus in Chinese hamster ovary (CHO) cells in vitro was investigated (BASF 2013). The assay was performed in two independent experiments, using two parallel cultures each. The first main experiment was performed at the following concentrations 0, 137.5, 275.0, 550.0, 1100.0 μg/mL. The second experiment was performed at the following concentrations 0, 200, 400, 800, 1100 μg/mL. The test item was dissolved in the aqueous culture medium (Ham's F12). Following attachment of the cells for 20-24 hours, cells were treated with the test substance for 4 in the absence of metabolic activation and for 4 hours in the presence of metabolic activation. Subsequently, cells were cultured for 6-8 days and then selected in 6-thioguaninecontaining medium for another week. Finally, the colonies of each test group were fixed with methanol, stained with Giemsa and counted. The vehicle controls gave mutant frequencies within the range expected for the CHO cell line. Both positive control substances, EMS and DMBA, led to the expected increase in the frequencies of forward mutations. In this study in the absence and the presence of metabolic activation no cytotoxicity was observed up to the highest required concentration evaluated for gene mutations. Based on the results of the present study, the test substance did not cause any relevant increase in the mutant frequencies either without S9 mix or after the addition of a metabolizing system in two experiments performed independently of each other. Thus, under the experimental conditions of this study, the test substance 3-Dimethylaminopropan-1-ol is not mutagenic in the HPRT locus assay under in vitro conditions in CHO cells in the absence and the presence of metabolic activation.

Micronucleus test (in vitro):

In a GLP compliant study performed according OECD guideline 487 the substance 3-Dimethylaminopropan-1-ol was assessed for its potential to induce micronuclei in V79 cells of the Chinese hamster in vitro (clastogenic or aneugenic activity). (BASF 2013). Two independent experiments were carried out, both with and without the addition of liver S9 mix from induced rats (exogenous metabolic activation). Based on the observations and the toxicity data of a previously performed pretest for a HPRT study the following concentrations were tested. In the first experiment with 4 hours exposure and 24 hours harvest time; with and without S9 mix: the concentrations 0, 34.4, 68.8, 137.5, 275, 550 and 1100 μg/mL were tested. The concentrations 275, 500, and 1100 µg/mL were evaluated for cytogenetic damage. In the second experiment without metabolic activation, 24 hours exposure, and 24 hours harvest time concentrations of 0, 34.4, 68.8, 137.5, 275, 550 and 1100 μg/mL were tested and the concentrations 34.4, 68.8 and 137.5 µg/mL were evaluated for cytogenetic damage. In the second experiment with metabolic activation, 4 hours exposure, and 24 hours harvest time, the concentrations 0, 137.5, 275, 550, 825 and 1100 μg/mL were tested and the concentrations 550, 825, and 1100 µg/mL were evaluated. A sample of at least 1000 cells for each culture were analyzed for micronuclei, i.e. 2000 cells for each test group. The vehicle controls gave frequencies of micronucleated cells within the historical negative control data range for V79 cells. Both positive control substances, EMS and cyclophosphamide, led to the expected increase in the number of cells containing micronuclei. In this study, cytotoxicity indicated by reduced relative increase in cell count (RICC) was observed at the highest applied test substance concentration after 24 hours continuous test substance treatment without S9 mix only. On the basis of the results of the present study, the test substance did not cause any biologically relevant increase in the number of cells containing micronuclei either without S9 mix or after adding a metabolizing system. Thus, under the experimental conditions described, 3-Dimethylaminopropan-1-ol is considered not to have a chromosome-damaging (clastogenic) effect nor to induce numerical chromosomal aberrations (aneugenic activity) under in vitro conditions in V79 cells in the absence and the presence of metabolic activation.

Short description of key information:
Dimethylaminopropanol did not cause gene mutations in Salmonella typhimurium (Ames test). The study was performed in the absence and presence of metabolic activation. The test substance, 3-Dimethylaminopropan-1-ol, is not mutagenic in the HPRT locus assay under in vitro conditions in CHO cells in the absence and the presence of metabolic activation. 3-Dimethylaminopropan-1-ol is considered to be non-mutagenic in the in vitro Micronucleus test system in V79 cells in the absence and the presence of metabolic activation.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Based on the results of the Ames tests, the in vitro micronucleus test, and the HPRT assay, dimethylaminopropanol does not need to be classified according to the EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.