Dodecanoic acid, ester with oxybis[propanediol]

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:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented publication which meets basic scientific principles. The test was performed within a oral subchronic toxicity study and no positive controls were included in the study.

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Genetic Toxicology Studies of SALATRIM Structured Triacylglycerols. Lack of Genetic Damage in in Vitro Mammalian Cell Assays and the in Vivo Micronucleus Assay

Author:

Hayes, J.R. et al.

Year:

1994

Bibliographic source:

J. Agrlc. Food Chem. 42, 521-527

Reference 2

Reference Type:

publication

Title:

Subchronic Toxicity Studies of SALATRIM Structured Triacylglycerols in Rats. 3. Triacylglycerols Composed of Stearate, Acetate, Propionate, and Butyrate

Author:

Hayes, J.R. et al.

Year:

1994

Bibliographic source:

J. Agric. Food Chem. 42, 552-562

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

yes

Remarks:

test was performed within an oral subchronic toxicity study and no positive controls were included.

Principles of method if other than guideline:

The rats received the test material in the diet for 13 weeks.

GLP compliance:

not specified

Type of assay:

micronucleus assay

Test material

Test material information

Constituent 1

Reference substance name:

short- and long-chain triacylglycerols (SALATRIM 234CA)

IUPAC Name:

short- and long-chain triacylglycerols (SALATRIM 234CA)

Constituent 2

Reference substance name:

short- and long-chain triacylglycerols (SALATRIM 234CS)

IUPAC Name:

short- and long-chain triacylglycerols (SALATRIM 234CS)

Details on test material:

- Name of test material (as cited in study report): only trade names given
- Lot/batch No.: A019 and A018
- Analytical purity: no data
- Composition of test material, percentage of components: see table 1 and 2 under "Any other information on materials and methods incl. tables".
- Other:
The test material lot A019 was produced from triacetin, tripropionin, tributyrin, and hydrogenated canola oil. This results in a relatively random distribution of acetic, propionic, and butyric acids among the short chain fatty acids (SCFA) esterified to glycerol.
The test material lot A018 was similar except the precursor fat was hydrogenated cottonseed oil. This resulted in a fat similar to the test material lot A019 with stearic acid still the predominant long chain fatty acid (LCFA) but with a slightly different distribution of other LCFA.

Test animals

Species:

rat

Strain:

other: Crl:CD BR VAF/Plus

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Portage, MI, USA
- Age at study initiation: 5-6 weeks
- Weight at study initiation: 150-201 g (males), 114-158 (females)
- Housing: animals were individually housed in stainless stell, wire-bottom cages
- Diet: NIH-07 Rat and Mouse Ration 5018 (Purina Mills, Inc), ad libitum
- Water: ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 50 ± 20
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: feed

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
The test material or corn oil were mixed separately with the diet.

DIET PREPARATION
- Rate of preparation of diet: every two weeks
- Mixing appropriate amounts with: NIH-07 Rat and Mouse Ration 5018
- Storage temperature of food: food for the first week was stored at room temperature, food for the second week was stored frozen at -5 to -20 °C.

Duration of treatment / exposure:

13 weeks

Frequency of treatment:

daily, 7 days/week

Post exposure period:

no

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
10% (w/w)
Basis:
nominal in diet

Doses / concentrations 2

Remarks:

Doses / Concentrations:
approx. 7000 mg/kg bw/day
Basis:
other: calculated based on measured food consumption

No. of animals per sex per dose:

20

Control animals:

other: yes, 10% corn oil in diet

Positive control(s):

Due to the study design as a 13-week subchronic toxicity study, no positive control for micronuclei formation was included.

Examinations

Tissues and cell types examined:

Tissue: bone marrow
Cell type: bone marrow cells

Details of tissue and slide preparation:

TREATMENT AND SAMPLING TIMES:
At necropsy, duplicate bone marrow slides for each rat were prepared for clinical pathology. One set of unstained bone marrow slides was shipped to a laboratory for the micronucleus assay.

DETAILS OF SLIDE PREPARATION/METHOD OF ANALYSIS:
Upon arrival, the slides were fixed in methanol and stained with acridine orange. A bone marrow slide from each of the 20 rat per group (with the exception of the test material lot A018 group, where only 18 slides were available) was analysed using fluorescent microscopy. One thousand polychromatic erythrocytes per rat were scored for micronuclei. Identification of micronuclei was based upon the criteria of Schmid (1976). The scoring unit was the micronucleated cell, not the number of micronuclei. Therefore, a cell that contained more than one micronucleus was scored as a single micronucleated cell. The frequency of micronucleated cells was expressed as percent micronucleated cells based upon the total number of polychromatic erythrocytes scored. The normal frequency of micronucleated erythrocytes for this strain of rat is 0.0-0.4% .

Evaluation criteria:

The criteria for a positive response was a significant increase in micronucleated polychromatic erythrocytes compared with the corn oil control group. If no increase was found, the test fats were considered negative in this assay.

Statistics:

Statistical analysis of the data was done by analysis of variance on the square root arcsine transformation. Tukey’s Studentized range test (Sokal and Rohlf, 1981) was used to determine statistical significance (p < 0.05) from the corn oil control group.

Results and discussion

Test results

Sex:

male/female

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

not examined

Additional information on results:

Comparison of the data for the two test substance fats with the results of the corn oil group indicated that neither of the test substances increased the incidence of micronucleated polychromatic erythrocytes. Therefore, the test materials were considered to be negative in the assay.

Any other information on results incl. tables

Table 3: Percent Micronucleated Polychromatic Erythrocytes in Bone Marrow of Rats Fed Diets Containing 10% of the test material Lot A019 or Lot A018 and Corn Oil for 13 Weeks (mean ± standard deviation, n= 18 -20 rats per sex per group).

Compound	(% MN/1000 PCE) Males	(% MN/1000 PCE) Females	(% MN/1000 PCE)  Combined males and females
Corn oil	0.18 ± 0.11	0.17 ± 0.13	0.17 ± 0.12
SALATRIM 234CA Lot A019	0.25 ± 0.17	0.17 ± 0.11	0.21 ± 0.14
SALATRIM 234CS Lot A018	0.21 ± 0.17	0.12 ± 0.12	0.16 ± 0.14

MN = micronucleated cells

PCE = polychromatic erythrocytes

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative