2-hydroxyethyl palmitate

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:

read-across based on grouping of substances (category approach)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study with acceptable restrictions.

Justification for type of information:

The Glycol ester category covers esters of an aliphatic diol (ethylene glycol (EG), propylene glycol (PG) or 1,3-butyleneglycol (1,3-BG)) and one or two carboxylic fatty acid chains. The fatty acid chains comprise carbon chain lengths ranging from C6 to C18, mainly saturated but also mono unsaturated C16 and C18, branched C18 and epoxidized C18.
 
The available data allows for an accurate hazard and risk assessment of the category and the category concept is applied for the assessment of environmental fate and environmental and human health hazards. Thus, where applicable, environmental and human health effects are predicted from adequate and reliable data for source substance(s) within the group by interpolation to the target substances in the group (read-across approach) applying the group concept in accordance with Annex XI, Item 1.5, of Regulation (EC) No 1907/2006. In particular, for each specific endpoint the source substance(s) structurally closest to the target substance is/are chosen for read-across, with due regard to the requirements of adequacy and reliability of the available data. Structural similarities and similarities in properties and/or activities of the source and target substance are the basis of read-across.
A detailed justification for the grouping of chemicals and read-across is provided in the technical dossier (see IUCLID Section 13).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

yes

Remarks:

analytical purity of test substance not specified.

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.12 (Mutagenicity - In Vivo Mammalian Erythrocyte Micronucleus Test)

Deviations:

yes

Remarks:

analytical purity of test substance not specified.

GLP compliance:

yes

Type of assay:

micronucleus assay

Test material

Test material information

Constituent 1

Reference substance name:

Reference substance 001

Cas Number:

151661-88-0

Details on test material:

- Name of test material (as cited in study report): Fatty acid C18 and C18 unsaturated epoxidized. Ester with ethylene glycol.
- Physical state: white powder
- Analytical purity: no data
- Lot/batch No.: No. 41, dated February 24, 1988, with the designation 041/8/055
- Storage condition of test material: room temperature

Test animals

Species:

mouse

Strain:

other: CFW1

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Winkelmann, Borchen, Germany
- Age at study initiation: 7-8 weeks
- Weight at study initiation: 20.7 - 32.8 g (males) and 19.5 - 24.8 g (females)
- Assigned to test groups randomly: yes, after delivery the animals were allocated to the treatment groups according to a randomization table generated by a computer program
- Fasting period before study: animals were fasted overnight prior to administration and until approx 3-4 hours after administration
- Housing: male mice were housed individually in macrolon cages type I, female mice were housed in groups up to three in macrolon cages type II
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 7 days (dose range finding study) and at least 4 - 6 days (main study)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 ± 3
- Humidity (%): 30-70
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

- Vehicle(s)/solvent(s) used: arachis oil
- Concentration of test material in vehicle:
Dose finding test: 300, 400 and 500 mg/mL
Main study: 500 mg/mL
- Amount of vehicle (if gavage or dermal): 10 mL/kg bw

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
The test substance was dissolved in arachis oil (80 °C and applied after cooling at a temperature of approx. 35 °C) at an application volume of 10 mL/kg. The test substance concentrations were prepared immediately before use. Homogeneity was maintained during application using a magnetic stirrer.

Duration of treatment / exposure:

3 days

Frequency of treatment:

single treatment

Post exposure period:

24, 48 and 72 h after treatment

Doses / concentrations

Remarks:

Doses / Concentrations:
5000 mg/kg bw/ day
Basis:
actual ingested

No. of animals per sex per dose:

6

Control animals:

yes, concurrent vehicle

Positive control(s):

- Cyclophosphamide
- Route of administration: intraperitoneal
- Doses / concentrations: 10 mg/kg bw, application volume 10 mL/kg bw

Examinations

Tissues and cell types examined:

Tissue: bone marrow
Cell type: bone marrow cells, erythrocytes

Details of tissue and slide preparation:

CRITERIA FOR DOSE SELECTION: As the acute oral toxicity (LD50 mouse) was determined to be higher than 5000 mg/kg bw according to acute toxicity studies the following doses were chosen initially to determine the maximum tolerated dose: 3000, 4000 and 5000 mg/kg. According to the results of the dose range finding study, a dose level of 5000 mg/kg bw was chosen for the main study, because it is generally recommended to use the maximum tolerated dose for the micronucleus test.

DETAILS OF SLIDE PREPARATION: Sliedes were air dried, fixed in methanol and stained with Giemsa according to modification of Gollapudi and Kamra.

METHOD OF ANALYSIS: Three slides per animal were prepared, one was randomly chosen and analysed. The slides of 5 males and 5 females per group were analysed and the ratio of polychromatic and normochromatic erythrocytes was determined by counting and differentiating the first 1000 erythrocytes at the same time.

Evaluation criteria:

The test is considered acceptable if the positive control substance induced statistically significant increase in polychromatic erythrocytes. The test is considered positive if the test substance induced biologically as well as statistically significant (p<0.05) increase in micronuclei at any dose either in the male or in the female groups. The test is considered negative if the test substance did not induce any biologically as well as statistically significant (p<0.05) increase in micronuclei at any dose either in the male or in the female groups.

Statistics:

Statistical significance of test substance values versus negative controls are calculated with the aid of tables of Kastenbaum and Bowman.

Results and discussion

Test results

Sex:

male/female

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

RESULTS OF RANGE-FINDING STUDY
- Dose range: 3000, 4000 and 5000 mg/kg bw
- Solubility: soluble
- Clinical signs of toxicity in test animals: none

RESULTS OF DEFINITIVE STUDY
- Induction of micronuclei (for Micronucleus assay): no statistically significant induction
- Ratio of PCE/NCE (for Micronucleus assay): no statistically significant deviations from 1
- Statistical evaluation: The investigated sample does not induce a statistically significant (time dependent) increase in the number of micronucleated polychromatic erythrocytes in the bone marrow of male or female mice.

Any other information on results incl. tables

Table 1: Mean values per group of PCE and PCE/NCE

Treatment group (sampling time	Species and sex	Dose	Mean of
			Micronucleated cells/ 1000 PCE	Ratio of PCE/NCE
Negative control (24 h)	male mice	10 mL/kg	1.6	1.0
	female mice		1.8	0.9
Positive control (24 h)	male mice	10 mL/kg	9.8	1.1
	female mice		7.4	1.0
Test substance
24 h	male mice	5000 mg/kg	2.4	1.1
	female mice		1.6	1.0
48 h	male mice	5000 mg/kg	1.2	1.0
	female mice		1.4	1.0
72 h	male mice	5000 mg/kg	1.2	1.3
	female mice		1.4	1.2

PCE: Polychromatic erythrocytes

NCE: Nonchromatic erythrocytes

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative