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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro cytogenicity / chromosome aberration study in mammalian cells
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Well conducted study, carried out by the Hatano research Institute, Food and Drug Safety Center (Japan), Guideline study, GLP; german translation available, only study summary is written English.

Data source

Referenceopen allclose all

Reference Type:
study report
Title:
Unnamed
Year:
1997
Report date:
1997
Reference Type:
publication
Title:
Relevance of chemical structure and cytotoxicity to the induction of chromosome aberrations based on the testing results of 98 high production volume industrial chemicals.
Author:
Kusakabe H, Yamakage K, Wakuri S, Sasaki K, Nakagawa Y, Watanabe M, Hayashi M, Sofuni T, Ono H, Tanaka N
Year:
2002
Bibliographic source:
Mutation Research 517 (1-2): 187-198

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)
Qualifier:
according to guideline
Guideline:
JAPAN: Guidelines for Screening Mutagenicity Testing Of Chemicals
GLP compliance:
yes
Type of assay:
in vitro mammalian chromosome aberration test

Test material

Constituent 1
Chemical structure
Reference substance name:
2-hydroxyethyl methacrylate
EC Number:
212-782-2
EC Name:
2-hydroxyethyl methacrylate
Cas Number:
868-77-9
Molecular formula:
C6H10O3
IUPAC Name:
2-hydroxyethyl methacrylate
Test material form:
liquid
Specific details on test material used for the study:
Supplier: Nippon Shokubai
Batch No. 5P05LA
Purity: 97.6 %
Ethylenglycol dimethacrylate: 0.2 - 0.3 %
Diethylenglycol monomethacrylate: 2.0 -2.5%
Stabilzer: 50 ppm Hydrochinon monomethylether

Method

Species / strain
Species / strain / cell type:
other: Chinese hamster lung (CHL/IU) cells
Cytokinesis block (if used):
The cytotoxic effect of the test substance on CHL/IU cells was determined using a monolayer cell density meter (Monocellater TM, manufactured by Olympus Kogaku Kogyo (AG)) by determining the growth rate for each group.
The cell growth was compared control group with /neutral/ medium. It was found that with both continuous and short-term medication, the cytotoxic did not exceed 50% at all concentrations used.
Metabolic activation:
with and without
Metabolic activation system:
Rat liver S9-mix
Test concentrations with justification for top dose:
-S9 mix (continuous treatment): 0, 0.16, 0.33, 0.65, 1.3 mg/ml; -S9-mix and +S9-mix(short-term treatment): 0, 0.33, 0.65 and 1.3 mg/ml
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: water
- Justification for choice of solvent/vehicle: solubility tests
Controls
Untreated negative controls:
not specified
Negative solvent / vehicle controls:
not specified
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: -S9 mix, Mitomycin C; +S9 mix, Cyclophosphamide S-9: Rat liver, induced with phenobarbital and 5,6-benzoflavone
Details on test system and experimental conditions:
Test duration: continous treatment: 24-hours                
short-term treatment: 6-hours
Plates/test: 2
Evaluation criteria:
A substance is considered clastogenic if: - any dose level shows
a statistically signicant increase in aberration-bearing
cells - the increase is over historical controls - the increase is present in both replicates
Statistics:
yes

Results and discussion

Test results
Species / strain:
other: Chinese hamster lung (CHL/IU) cells
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
other: Toxicity was not observed up to 0.65 mg/ml in continuous and short-term treatment with or without S9-mix.
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Additional information on results:
Structural chromosomal aberrations (including gap) were induced under the following conditions: 
24 h continuous treatment (0.65 and 1.3 mg/ml: mid and high concentrations, 10.0 and 70.6 %, respectively); 
48 h continuous treatment (0.16 - 0.65 mg/ml: all concentrations, 6.0 - 84.0 %);
short-term treatment with an exogenous metabolic activation system (1.3 mg/ml: high concentration, 13.0 %). 
Polyploidy was induced under the following conditions: the 48 h continuous treatment (0.65 mg/ml, 3.25 %); 
short-term treatment with an exogenous metabolic activation system (0.65 mg/ml: mid concentration, 1.25 %); 
short-term treatment without the metabolic activation system (0.33 and 1.3 mg/ml: low and high concentrations, 0.88 and 6.13 %, respectively). 
However, a trend test showed no dose-dependency for the  polyploidy with short-term treatment and the metabolic activation system.
Lowest concentration producing cytogenetic effects in vitro:
Without metabolic activation (continuous treatment): 0.16 mg/ml (clastogenicity)                           
0.65 mg/ml (polyploidy)
Without metabolic activation (short-term treatment):  0.33 mg/ml (polyploidy)
With metabolic activation (short-term treatment): 1.3 mg/ml (clastogenicity)      
0.65 mg/ml (polyploidy)

Any other information on results incl. tables

Result table see under attachments

Applicant's summary and conclusion

Conclusions:
Interpretation of results:
positive

Structural chromosomal aberrations (including gap) were induced under the conditions of the study.
Executive summary:

HEMA has been evaluated for its ability to induce chromosomal aberrations in mammalian cells in culture (MHW 1997). Kusakabe et al. (2002) evaluated the clastogenic potential of HEMA along with a large number of other substances in Chinese hamster lung cells in culture, exposed to concentrations up to 1.3 mg/ml. HEMA was reported to induce structural chromosome aberrations following 6-hour exposure of cells but only in the presence of S9 at 1.3 mg/ml. Continuous exposure of cells for 24 or 48 hours without S9 also caused an elevated incidence of chromosome aberrations (from 0.16 mg/ml for the 48-hour exposure and from 0.65 mg/ml for the 24-hour exposure). Polyploidy was reported after both short-term treatment and 48-hour continuous treatment exposures. However, no dose-dependency was observed for polyploidy in the short-term treatment with metabolic activation. These effects were found at exposure levels without cytotoxicity or at concentrations which caused <50% cell death (no toxicity up to 0.65 mg/ml). For careful interpretation of these results two publications by Fujita et al (2016) should be considered. If the cytotoxicity index relative cell count (RCC) is replaced with a new index, RICC or RPD (relative increase in cell count/relative population doubling), the result was identified as being possibly false positive.