Methyl vinyl ether

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

-in vitro bacteria gene mutation: negative
-in vitro mammalian gene mutation: negative

Genetic toxicity in vivo

Description of key information

-no clastogenic or aneugenic effects in the mouse micronucleus test

Additional information

In vitro gene mutation in bacteria

Methyl vinyl ether was not mutagenic in S. typhimurium TA98, TA100, TA1535, TA1537, TA1538 in the presence or absence of metabolic activation at vapour concentrations from 0.5 to 25% in two independent trials. Atmospheres containing 25% of the test substance were cytotoxic (GAF 1979).

In a 2nd study (Araki 1994) also no mutagenic activity was detected in Salmonella typhimurium TA98, TA100, TA1535, TA1537, and E.coli WP2 uvrA tested with and without metabolic activation at cytotoxic vapour concentration and/or the max. vapour concentration of 50%.

In vitro gene mutation in mammalian cells

Methyl vinyl ether (Cas: 107-25-5) was assessed for its potential to induce gene mutations at the hypoxanthine-guanine phosphoribosyl transferase (HPRT) locus in Chinese hamster ovary (CHO) cells in vitro. Two independent experiments were carried out, both with and without the addition of liver S9 mix from phenobarbital- and β-naphthoflavone induced rats (exogenous metabolic activation). Test groups in1st Experiment with and without S9 mix 0; 1250.0; 2500.0; 5000.0; 10000.0; 20000.0μg/mL. In the 2nd Experiment without S9 mix 0; 2500.0; 5000.0; 10000.0; 15000.0; 20000.0μg/mL and with S9 mix 0; 1250.0; 2500.0; 5000.0; 10000.0; 15000.0; 20000.0μg/mL. Cells were treated with the test substance for 4 hours in the absence and presence of metabolic activation. The vehicle controls gave mutant frequencies within the range expected for the CHO cell line. Both positive control substances, ethyl methane sulfonate (EMS) and 7,12-dimethylbenz[a]- anthracene (DMBA), led to the expected statistically significant increase in the frequencies of forward mutations. Without metabolic activation, no cytotoxicity occurred up to the highest applied concentration. After the addition of a metabolizing system, cytotoxicity was observed in both experiments at least at the highest concentrations evaluated for gene mutations. Thus, under the experimental conditions of this study, the test substance methyl vinyl ether is not mutagenic in the HPRT locus assay under in vitro conditions in CHO cells in the absence and the presence of metabolic activation (BASF, 2017).

In vivo micronucleus test

No signs of toxicity were noted in male and female CD-1 mice repeatedly exposed to MVE at 5000 or 25000 ppm (n=5 per dose per sex; 6 h/day for 5 days; the high dose level is very close to the lower explosion level; corresponding to 0; 12; 60 mg/L). Examination of erythrocytes from bone marrow (sacrifice 24 h after the last exposure) gave no indication of an induction of clastogenic/aneugenic effects or cytotoxicity. Vehicle control and positive control were valid. Positive results seen in only one subgroup (high-dose males) in a previous study are outweighed and attributable to some technical flaw in the procedure (BG Chemie 1987).

In a 2nd micronucleus test (Dow 1990) MVE did not produce dose related or biologically significant increases in the incidence of micronucleated polychromatic erythrocytes in the peripheral blood of Swiss-Webster mice (5 mice per sex and dose) at concentrations of 0, 5000, 10000, and 19500 ppm (12, 24, and 47 mg/L) in a study performed in accordance with EPA guidelines. The blood samples were obtained at 30, 48, and 72 hours after a single 6-hour whole-body vapor exposure.

Short description of key information:
-in vitro bacteria gene mutation: negative
-in vitro mammalian gene mutation: negative
-no clastogenic or aneugenic effects in the mouse micronucleus test

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Classification for genetic toxicity is not warranted according to the criteria of EU Directive 67/548/EEC and EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.