Enbucrilate

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study and GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: Tests for Genotoxicity, Carcinogenicity and Reproductive Toxicity; ISO 10993-3 (1992)

GLP compliance:

yes

Type of assay:

micronucleus assay

Test material

Test material information

Constituent 1

Reference substance name:

Polymerised Indermil

IUPAC Name:

Polymerised Indermil

Constituent 2

Reference substance name:

Enbucrilate

EC Number:

229-552-2

EC Name:

Enbucrilate

Cas Number:

6606-65-1

Molecular formula:

C8H11NO2

IUPAC Name:

butyl 2-cyanoprop-2-enoate

Test material form:

other: extract

Details on test material:

TEST ARTICLE:
- Polymerised Indermil (n-butylcyanoacrylate, CAS 6606-65-1) - Disk (Area 64.7cm2 approx, 4g weight - 2 pieces )
- Lot/Batch Number: U02B41, Lab Book Refs: 2696/74-48; 2696/74-55
- Physical State: Solid
- Color: Amber
- Density: N/S
- Stability: Highly Stable
- Solubility: Practically insoluble
- Expiration Date: N/S
- Storage Conditions: Room Temperature
- Safety Precautions: Standard Toxikon Laboratory Safety Precautions

NEGATIVE CONTROL ARTICLE:
- 0.9% USP Sodium Chloride for Injection (NaCl)
- Toxikon QC#: CSC-02-01-002-VIV
- Physical State: Liquid
- Color: Clear, Colorless
- Storage Conditions: Room Temperature
- Safety Precautions: Standard Laboratory Safety Precautions

POSITIVE CONTROL ARTICLE:
- Mitomycin C (MMC)
- Toxikon QC #: CSC-02-03-017-CC
- Physical State: Solid
- Color: White
- Storage Conditions: 4±2°C
- Safety Precautions: Standard Laboratory Safety Practices

Test animals

Species:

mouse

Strain:

Swiss

Sex:

male/female

Details on test animals or test system and environmental conditions:

ANIMALS:
38 Swiss Albina mice (mus musculus)
- Weight range: 22.9 to 34.6 g (weighed to the nearest 0.1 g)
- Age: at least 6 weeks old (adult)
- Animal Identification: ear punch
- Animal purchase: Harlan, Indianapolis, IN.
- Acclimatization: Minimum 5 days und er the same conditions as for the actual test.
- Animal Selection: selected from a larger pool of animals and examined to ensure lack of adverse clinical signs.

CARE AND MAINTENANCE:
- Housing: group housing (5 of same sex/cage)
- Cages: polycarbonate cages
- Bedding: hardwood chips (contact): P.W.I. Industries, St-Hyacinthe, Quebec, Canada
- Animal room temperature: 68±5°F
- Animal room relative humidity: 30-70%
- Air exchanges per hour: 10 to 15
- Lights: 12-hour light/dark cycle, full spectrum fluorescent lights
- The laboratory and animal rooms were maintained as limited-access facilities.
- Animal rations: TEK 7012, Rodent Diet, Harlan Teklad, Madison, WI
- Water: tap water, ad libitum
There were no known contaminants present in the feed, water, or bedding expected to interfere with the test data.

Administration / exposure

Route of administration:

intravenous

Vehicle:

NaCl

Duration of treatment / exposure:

single injection

Frequency of treatment:

once

Post exposure period:

24h and 48h

Doses / concentrations

Remarks:

Doses / Concentrations:
50mL/kg bw
Basis:
other: extract in NaCl (0.2g/mL)

No. of animals per sex per dose:

TOTAL: 19 males and 19 females
- TEST: 10 each (5 males and 5 females) for 24h or 48h
- NEGATIVE CONTROL: 6 each (3 males and 3 fmeales) for 24h or 48h respectively
- POSITIVE CONTROL: 6 (3 males and 3 fmeales) for 24h

Control animals:

yes

Positive control(s):

Mitomycin C (200 µg/kg bw, dissolved in NaCl) intraperitoneal

Examinations

Tissues and cell types examined:

bone marrow (femur) / erythrocytes

Evaluation criteria:

EVALUATION: The number of micronucleated polychromatic erythrocytes for the positive and negative controls should be in the range of expected historical control values. The frequency of micronucleated PCEs in the positive control group should be statistically significantly greater than the negative control group. If these conditions are not met the test should be repeated.

POSITIVE RESPONSE: The test article was considered to have caused a positive response in the assay if the test article had exhibited a reproducible and statistically significant increase over its concurrent negative control article.

Statistics:

Data was analyzed separately for male and female animals. The frequency of micronucleated PCEs in each dose group was compared to that in the respective negative control and to each other using the program: "Newman-Keuls Test" by R.J. Tallarida and R.B. Murray, (Manual of Pharmacologic Calculations with Computer Programs, Springer-Verlag, New York, 1986, pp. 121- 125). Biological and statistical significance was considered in the evaluation. Results were considered not significant with p>=0.05.

Results and discussion

Test results

Sex:

male/female

Genotoxicity:

negative

Toxicity:

yes

Remarks:

lethargy and clonic convulsions immediately after injections only

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Any other information on results incl. tables

ANIMAL WEIGHTS, DOSING AND CLINICAL OBSERVATIONS:

Animal weight (prior to dosing and prior to sacrifice), dosing data and clinical observations were recorded for all the animals, during the course of the study. All animals had gained weight at the time of sacrifice.

Eight Animals out of the test article group showed signs of lethargy and clonic convulsions immediately after injections. These signs of clinical toxicity were resolved by the 24-hour observation and did not impact on the mutagenicity properties of the test article. No other clinical signs of toxicity were observed for any of the test or control animals.

MICRONUCLEUS SCORING:

There was a statistically significant increase in the number of micronucleated cells in the positive control group, as compared to the negative control group, thus validating the conduct of the assay.

There was no statistically significant increase in the number of micronucleated cells in the test article extract group at all time points, as compared to the concurrent negative control groups.

AVERAGE RESULTS PER GROUP

 

Group	PCE	NCE	PCE/NCE	MNC	MNC/PCE	Weight change
Test article 24h (male)	2000	1675	1.20	4.20	0.0021	+ 2.04 g
Test article 24h (female)	2000	1637	1.23	4.00	0.0020	+ 1.76 g
Test article 48h (male)	2000	1626	1.23	4.40	0.0022	+ 2.12 g
Test article 48h (female)	2000	1603	1.25	4.60	0.0023	+ 1.54 g
Negative control 24h (male)	2000	1614	1.24	5.00	0.0025	+ 1.50 g
Negative control 24h (female)	2000	1667	1.20	4.67	0.0023	+ 1.67 g
Negative control 48h (male)	2000	1745	1.15	5.67	0.0028	+ 2.00 g
Negative control 48h (female)	2000	1656	1.21	5.33	0.0027	+ 1.37 g
Positve control 24h (male)	2000	1979	1.02	57.33	0.0287	+ 1.90 g
Positve control 24h (female)	2000	2181	0.92	62.00	0.0310	+ 1.67 g

 

PCE: Polychromatic Erythrocytes

NCE: Normochromatic Erythrocytes

MNC: Micronucleated Cells

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative
The test article, Polymerised Indermil (n-butylcyanoacrylate), is considered non-mutagenic, under the experimental conditions utilized.

Executive summary:

SUMMARY

The extract of the test article was tested for its ability to induce a statistically significant increase in the number of micronucleated cells in rodent bone marrow. The 0.9% USP Sodium Chloride for Injection (NaCl) extract of the test article, Polymerised Indermil (n-butylcyanoacrylate), was tested at the neat concentration, and did not induce a statistically significant increase in micronucleated cells as compared to the negative control at 24 and 48 hours after dosing. The positive control, Mitomycin C, caused a statistically significant increase in micronucleated cells as compared to the negative control.

Based on the criteria ofthe study protocol, the test article, Polymerised Indermil (n-butylcyanoacrylate), is considered non-mutagenic, under the experimental conditions utilized.