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Administrative data

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information
GLP and non-GLP studies equivalent to OECD guidelines 471, 473 and 482 are available for propylene glycol methyl ether. In addition non-GLP studies equivalent to OECD guidelines 476, 479 and 474 are available.
Link to relevant study records
Reference
Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: gene mutation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1983
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP study, equivalent to OECD guideline no. 471.
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay
Species / strain / cell type:
other: salmonella typhimurium strains TA 1535, TA 1537, TA 1538, TA 98, TA 100
Metabolic activation:
with and without
Metabolic activation system:
S9 rat liver homogenate (aroclor 1254 induced)
Test concentrations with justification for top dose:
2; 10; 50; 250; 1250; 6250 µg/plate
Vehicle / solvent:
none (test material solutions were prepared in distilled water), DMSO for positive controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene (TA98, TA100, TA1535, TA1537/+S9); 4-nitro-o-phenylenediamine (TA98, TA 1538/-S9); N-methyl-N'-nitrosoguanidine (TA100, TA1535, TA 1537/-S9)
Details on test system and experimental conditions:
METHOD OF APPLICATION: plate incorporation

- Incubation period: 48 hours

NUMBER OF REPLICATIONS:
3 replicates per dose / 2 independent repeats

DETERMINATION OF CYTOTOXICITY
- Method: bacterial background lawn evaluation
- no cytotoxcity observed
Evaluation criteria:
Concentrations of the test chemical which are overtly toxic are easily visualized as showing no bacterial growth on the plate (i.e. absence of background lawn). Lower levels of toxicity may be seen as a thin or sparse bacterial lawn, a reduction in the number of revertants, or the appearance of microcolonies (overgrown background lawn). Positive and negative controls were run concurrently with the test chemical, and appropriate responses for these controls are prerequesites for evaluating the response of the bacteria to the test chemical.

A test chemical is considered a bacterial mutagen if both the mean number of revertant colonies observed is at least three times higher than the mea
Statistics:
Means and standard deviations for each treatment were calculated and recorded. An analysis of variance was performed on ecah set of data to give the F-statistic.
Species / strain:
other: salmonella typhimurium strains TA 1535, TA 1537, TA 1538, TA 98, TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

See attachments for supportive graphs and tables.

Conclusions:
Interpretation of results (migrated information):
negative

Dowanol Propylene glycol methyl ether (Dowanol PM) did not cause mutations in the Ames Salmonela reverse mutation assay both with or without S-9 metabolic activation. Hence, the test material was classified as negative in the Ames test under the experimental conditions used.
Executive summary:

Propylene glycol methyl ether was evaluated in the Salmonella/mammalian-microsome bacterial mutagenicity assay (Ames test) using a plate incorporation assay. The test was conducted using Salmonella typhimurium bacetrial tester strains TA98, TA100, TA1535, TA 1537 and TA1538 at 6 doses in triplicate. The test agent was assayed at 2, 10, 50, 250, 1250, 6250 µg/plate.

The assay was repeated independently . All solvent (negative) control plates and positive control plates gave frequencies of induced revertants within expected ranges. Slight variation in the control were seen for most of the strains with S-9 in both the experiments but was quite normal (not significant).

No evidence of toxicity or insolubility was seen in experiment upto 6250 µg/plate, which is highest dose used.

The test material did not induce a mutagenic response in any of the tester strains in either of the assays as judged by the frequencies of histidine-independent (his+) revertants. Hence, the test material was classified as negative in the Ames under the experimental conditions used.

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

Additional information

Additional information from genetic toxicity in vitro:

Genetic toxicity in vitro: propylene glycol methyl ether showed negative results in a series of Ames tests. Effects on lung (V79) cells of Chinese hamsters included cell growth inhibition, slight increase in Sister Chromatide Exchanges (SCEs), and dose dependent inhibition on intercellular communication (at non-cytotoxic levels). However, SCEs were only noted at very high concentrations, and the resulting dose response correlation was weak. As such, these data are not convincing of a true genotoxic effect. Propylene glycol methyl ether was not toxic to Chinese hamster ovary (CHO) cells at concentrations up to 5 mg/mL. However, survival was decreased to 50% at 10 mg/mL. Treatment of cells with propylene glycol methyl ether resulted in a few marginal increases in gap and aberrations at some doses in the absence of S9, but none of these were statistically significant. In the presence of S9, frequencies of gaps and aberrations all decreased from the solvent control with propylene glycol methyl ether pre-treatment.

Genetic toxicity in vivo: Concentrations up to 6,000 mg/kg administered to mice did not increase the frequency of micronuclei in polychromatic erythrocytes harvested from bone marrow.


Justification for selection of genetic toxicity endpoint
GLP and guideline conforming study

Justification for classification or non-classification

Propylene glycol methyl ether was not mutagenic in bacteria (Salmonella typhimuriumTA 1535, TA 1537, TA 1538, TA 98, and TA 100), in vitro in mammalian cells, or in vivo in mice. The data available indicates that propylene glycol methyl ether is not genotoxic.