2-(hydroxymethylamino)ethanol

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from USEPA HPV report

Data source

Reference

Reference Type:

review article or handbook

Title:

Genetic Toxicity in vivo Ethanol, 2-(hydroxymethylamino) _ (CAS# 34375-28-5)

Author:

US EPA HPV Chemical Challenge Program- Troy Corporation

Year:

2005

Bibliographic source:

U.S Environmental Protection Agency/ High Production Volume Information System (HPVIS) 2005

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Principles of method if other than guideline:

Genetic toxicity in vivo test was conducted to assess the potential induction of micronuclei by 2-(Hydroxymethyl) aminoethanol in bone marrow cells of mice.

GLP compliance:

no

Type of assay:

micronucleus assay

Test material

Test material information

Constituent 1

Reference substance name:

2-(hydroxymethylamino)ethanol

EC Number:

251-974-0

EC Name:

2-(hydroxymethylamino)ethanol

Cas Number:

34375-28-5

Molecular formula:

C3H9NO2

IUPAC Name:

2-[hydroxy(methyl)amino]ethanol

Details on test material:

- Name of test material: Troysan 174
- Molecular formula: C3H9NO2
- Molecular weight: 91.1091 g/mol
- Substance type: Organic
- Physical state: Liquid
- Purity: 74.3%
- Impurities (identity and concentrations): No data available

Specific details on test material used for the study:

- Name of test material: Troysan 174, (2[(Hydroxymethyl)amino] ethanol)
- IUPAC name: 2-[hydroxy(methyl)amino]ethanol
- Molecular formula: C3H9NO2
- Molecular weight: 91.1091 g/mol
- Substance type: Organic
- Physical state: No data
- Purity: 74.3 %
- Impurities (identity and concentrations): 26.7%

Test animals

Species:

mouse

Strain:

CD-1

Details on species / strain selection:

No data

Sex:

male/female

Details on test animals or test system and environmental conditions:

No data available

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

- Vehicle(s)/solvent(s) used: water
- Justification for choice of solvent/vehicle: The test chemical was soluble in water
- Concentration of test material in vehicle: 0, 150, 300 and 600 mg/kg
- Amount of vehicle (if gavage or dermal): No data available
- Type and concentration of dispersant aid (if powder): No data available
- Lot/batch no. (if required): No data available
- Purity: No data available

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: The test chemical was dissolved in water to give a dose range of 0, 150, 300 or 600 mg/Kg

DIET PREPARATION
- Rate of preparation of diet (frequency): No data
- Mixing appropriate amounts with (Type of food): No data
- Storage temperature of food: No data

Duration of treatment / exposure:

Duration of test: 72 hrs
Duration of exposure: 24, 48 or 72 hours

Frequency of treatment:

Single dose

Post exposure period:

No data available

Doses / concentrations

Remarks:

0, 150, 300 and 600 mg/kg

No. of animals per sex per dose:

Total: 140
0 mg/Kg bw: 15 males and 15 females
150 mg/Kg bw: 15 males and 15 females
300 mg/Kg bw: 15 males and 15 females
600 mg/Kg bw: 20 males and 20 females
Positive control: 5 males and 5 females

Control animals:

yes, concurrent vehicle

Positive control(s):

- Positive controls: Mitomycin C
- Justification for choice of positive control(s): No data
- Route of administration: oral by intragastric gavage.
- Doses / concentrations: 12 mg/kg bodyweight

Examinations

Tissues and cell types examined:

bone marrow cell

Details of tissue and slide preparation:

No data available

Evaluation criteria:

A positive response is normalyy indicated by a substantial, statistically significant increase (P< 0.01) in the incidence of micronucleated polychromatic erythrocytes compared to the incidence for the concurrent vehicle control group for at least one of the dampling times; Individual and/or group mean values should exceed the laboratory historiacal control range. A negative result is indicated where individual and group mean incidences of micronucleated polychromatic erythrocytes for animals treated with the test substance are not significantly greater (P> 0.01) than incidences for the concurrent control gorup and where these values fall within the historical control range. An equvivalent response is obtained when the resukts cannot be adequately classified using the criteria for a positive or negative response.

Bone marrow cell toxicity (or depression) is normally indicated by a substantial, statistically significant decrease (P<00.1) in the ration of polychromatic to normochromatic erythrocytes. This decrease would normally be evident at both the 48 and 72 hrs sampling points, a decrease at the 24 hour point is not necessarily expected because of the relatively long transition time of erythroid cells. A very large decrease in this ration would be indicative of a cytotoxic effect.

Statistics:

Kruskal-Wallis’s test, Jonckheere’s test for trend, Wilcoxon’s sum of ranks test

Results and discussion

Test results

Sex:

male/female

Genotoxicity:

negative

Toxicity:

not specified

Vehicle controls validity:

valid

Negative controls validity:

not specified

Positive controls validity:

valid

Remarks:

Mitomycin C did not cause any statistically significant decreases in the p/a ratio at the 24 hour sampling time [P>0.01 using Wilcoxon’s sum of ranks test].

Additional information on results:

RESULTS OF RANGE-FINDING STUDY
- Dose range: A preliminary toxicity test had previously shown 600 mg/kg to be approximately the maximum tolerated dosage.
- Solubility: No data available
- Clinical signs of toxicity in test animals: None of these animals showed signs of misdosing at post mortem examination. No adverse clinical signs were obtained for the vehicle control or positive control treated animals over the duration of the test
- Evidence of cytotoxicity in tissue analyzed: No data available
- Rationale for exposure: No data available
- Harvest times: No data available
- High dose with and without activation: No data available
- Other:

RESULTS OF DEFINITIVE STUDY
- Types of structural aberrations for significant dose levels (for Cytogenetic or SCE assay): No data available

- Induction of micronuclei (for Micronucleus assay): A slight but statistically significant increase (P< 0.01 using Kruskal-Wallis’s test) in the frequency of micronucleated polychromatic erythrocytes was obtained at the 24 hour sampling time for animals treated at the intermediate level (300 mg/kg) of the test substance. This increase was small and was not dose related (P>0.01 using Jonckheere’s test for trend) and was not apparent at the later sampling times. Slides from this group along with those from the concurrent vehicle control were re-examined by a second slide reader and, in this instance, no significant increase in the incidence of micronucleated polychromatic erythrocytes was recorded. In all cases the group mean and individual animal incidence of micronucleated polychromatic erythrocyte values obtained were well within the laboratory historical control range. The increase recorded in the original examination is therefore thought to be the result of chance variation and is not indicative of chromosome damage. At all other sampling times and does levels, mice treated with 2-(Hydroxymethyl)aminoethanol did not show any significant increase in the frequency of micronucleated polychromatic erythrocytes.

- Ratio of PCE/NCE (for Micronucleus assay): There was no significant decrease in the ratio of polychromatic to normochromatic erythrocytes after treatment

- Appropriateness of dose levels and route: No data available

- Statistical evaluation: No data available

Any other information on results incl. tables

Table: Micronucleus test- mortality data

Dose (mg/Kg)	Mortality ratio (No. of deaths/ No. dosed)
	Male	Female	Combined
0	0/15	0/15	0/30
150	0/15	0/15	0/30
300	0/15	0/15	0/30
600	3/20	5/20	8/40
Mitomycin C (12 mg/Kg)	0/5	0/5	0/10

Applicant's summary and conclusion

Conclusions:

Ethanol, 2-(hydroxymethylamino) did not show any evidence of causing chromosome damage or bone marrow cell toxicity when administered orally to CD-1 mouse. Hence, the substance Ethanol, 2-(hydroxymethylamino) is not genotoxic to CD-1 mouse.

Executive summary:

Genetic toxicity in vivo test was conducted to assess the potential induction of micronuclei by 2-(Hydroxymethyl) aminoethanol in bone marrow cells of mice. 15 male and 15 female mice per dose were treated with a single acute oral administration of the test substance by intragastric gavage at dosages of 0, 150, 300 and 600 mg/kg. Mitomycin C used as positive control at 12 mg/kg bodyweight and water was used as solvent control.

Bone marrow smears were obtained from five male and five female animals in the negative control and test substance groups at 24, 48 or 72 hours after dosing. Bone marrow smears were obtained from the positive control group 24 hours after dosing. One smear from each animal was examined for the presence of micronuclei in 1000 polychromatic erythrocytes. The ratio of polychromatic to normochromatic erythrocytes was assessed by examination of at least 1000 erythrocytes from each animal.

Three male and five female animals died after treatment with the highest level of 2-(Hydroxymethyl)aminoethanol in the micronucleus test. At post mortem examination, none of these animals showed signs of misdosing. No adverse clinical signs were obtained for the vehicle control or positive control treated animals over the duration of the test. A slight but statistically significant increase in the frequency of micronucleated polychromatic erythrocytes was obtained at the 24 hour sampling time for animals treated at the intermediate level (300 mg/kg) of the test substance. This increase was small and was not dose related and was not apparent at the later sampling times. There was no significant decrease in the ratio of polychromatic to normochromatic erythrocytes after treatment of the animals with 2-(Hydroxymethyl)aminoethanol. Ethanol, 2-(hydroxymethylamino) did not show any evidence of causing chromosome damage or bone marrow cell toxicity when administered orally to CD-1 mouse. Hence, the substance Ethanol, 2-(hydroxymethylamino) is not genotoxic to CD-1 mouse.