(5-ethyl-1,3-dioxan-5-yl)methyl acrylate

Endpoint summary

Additional information

Gene mutation in bacteria

5 -ethyl-1,3 -dioxan-5 -yl-methyl acrylate was not mutagenic in a standard plate test and in a pre-incubation Ames test with and without metabolic activation, tested up to 6500 μg/plate (adjusted to purity, equals 5000µg/plate pure substance) in Salmonella typhimurium strains TA1535, TA 1537, TA 98 and TA 100 and E.coli WP2 uvrA. S9 fraction was prepared from the liver of male Sprague-Dawley rats, treated with a single dose of phenobarbital and β-naphthoflavone. Cytotoxicity was observed >1000 µg/plate, depending on test strain and test conditions.

Gene mutation in mammalian cells

5 -ethyl-1,3 -dioxan-5 -yl-methyl acrylate was also not mutagenic in a HPRT assay using CHO cells. After an attachment period of 20 - 24 hours and a treatment period of 4 hours both with and without metabolic activation and 24 hours without metabolic activation, an expression phase of about 6 - 8 days and a selection period of about 1 week followed. The colonies of each test group were fixed with methanol, stained with Giemsa and counted. S9 fraction was prepared from the liver of male Sprague-Dawley rats, treated with a single dose of phenobarbital and β-naphthoflavone. The doses used were selected according to the cytotoxic properties of the test substance as determined in a range-finding study:

• 4 hours exposure -S9: 1.25, 2.5, 5, 10µg/ml
• 24 hours exposuse -S9: 0.63, 1.25, 2.5, 5µg/ml
• 4 hour exposure +S9: 10, 20, 40, 80µg/ml (1st experiment) 12.5, 25, 50, 100µg/ml (2nd experiment)

Cytotoxicity was observed at the next higher dose used.

 

Genetic toxicity in vivo

A micronucleus test was conducted using the intraperitoneal route in groups of seven mice (males) at the maximum tolerated dose (MTD) 300 mg/kg and at 150 and 75 mg/kg. Animals were killed 24 or 48 hours (only high dose) later, the bone marrow was extracted, and smear preparations made and stained. Polychromatic ( PCE) and normochromatic (NCE) erythrocytes were scored for the presence of micronuclei. 7 mice were dosed intraperitoneally with arachis oil as negative control, and 5 futher mice dosed orally with cyclophosphamide served as positive control.

Hunched posture, ptosis, tip-toe gait, and pilo-erection were observed in animals of all groups. A modest statistically significant decrease in the PCE/NCE ratio was observed in the 24-hour 300 mg/kg test item group when compared to the vehicle control group. Although not statistically significant, modest decreases in the PCE/NCE ratio were also observed after 48 -hour in high dose mice and in animals of the 150 mg/kg group. These decreases, together with the observation of clinical signs, were taken to indicate that systemic absorption had occurred and exposure to the target tissue had been achieved.

There was no evidence of a significant increase in the incidence of micronucleated polychromatic erythrocytes in animals dosed with the test item when compared to the vehicle control group. Positive control mice showed the expected increase in micronucleated

polychromatic erythrocytes.

Short description of key information:
Genetic toxicity in vitro:
Ames negative (OECD 471, GLP, BASF 2012)
HPRT negative (OECD 476, GLP, BASF 2012)

Genetic toxicity in vivo
MNT (i.p.) negative (OECD 474, GLP, Sun Chemicals 2011)

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

5 -ethyl-1,3 -dioxan-5 -yl-methyl acrylate did not induce gene mutations in bacteria or mammalian cells. It was also non-genotoxic in an in vivo micronucleus test, while inducing systemic toxicity. Thus, the substance has not to be classified according to EU criteria (67/548/EEC) or CLP/EU-GHS for genetic toxicity.