A mixture of isomers of branched tetracosane

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Between 27 October 1994 and 17 November 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

adopted 24 Feb 1987

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OTS 798.1175 (Acute Oral Toxicity)

Version / remarks:

Toxic Substances Control Act (TSCA), Health Effects Testing Guidelines: Subpart 8, Section 798.1175 "Acute Oral Toxicity"

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPP 81-1 (Acute Oral Toxicity)

Version / remarks:

FIFRA, Pesticide Assessment Guidelines Subdivision F; Hazard Evaluation Human and Domestic Animals Section 81-1 "Acute Oral Toxicity Study". Revised Edition Nov 1984.

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

The work described was performed in compliance with the UK principles of Good Laboratory Practice (The United Kingdom Compliance Programme, Department of Health 1989).

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

A mixture of isomers of branched tetracosane

EC Number:

417-060-2

EC Name:

A mixture of isomers of branched tetracosane

Cas Number:

151006-61-0

Molecular formula:

C24 H50

IUPAC Name:

A mixture of isomers of branched tetracosane

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source:
Charles River (UK) Ltd., Margate, Kent, UK.

- Age at study initiation:
Approximately eight weeks old.

- Weight at study initiation:
The males weighed 207 - 234 g and the females 202 - 219 g.

- Fasting period before study:
Overnight fast immediately before dosing and two hours after dosing.

- Housing:
Housed in groups of five by sex in grid bottom polypropylene cages.

- Diet (e.g. ad libitum):
Free access to food (Rat and Mouse Expanded Diet No. 1, Special Diets Services Limited, Witham, Essex, UK) was allowed throughout the study.

- Water (e.g. ad libitum):
Free access to water was allowed throughout the study

- Acclimation period:
Minimum acclimation period of at least seven days

ENVIRONMENTAL CONDITIONS
- Temperature (°C):
The animal room was maintained at a temperature of 19 to 21 deg C

- Humidity (%):
The animal room was maintained at a relative humidity of 49 to 54%

- Air changes (per hr):
The rate of air exchange was approximately 15 changes per hour

- Photoperiod (hrs dark / hrs light):
Lighting was controlled by a time switch to give 12 hours continuous light and 12 hours darkness.


IN-LIFE DATES: From: Day one To: Day fourteen

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

VEHICLE
- Concentration in vehicle:
Not applicable

- Amount of vehicle (if gavage):
Not applicable

- Justification for choice of vehicle:
Not applicable

- Lot/batch no. (if required):
Not applicable

- Purity:
Not applicable

MAXIMUM DOSE VOLUME APPLIED:
6.28 ml/kg


DOSAGE PREPARATION (if unusual):
For the purpose of the study the test material was used as supplied. The specific gravity was determined by Safepharm Laboratories Limited and used to calculate the appropriate dose volume for the required dose level.
The absorption of the test material was not determined.

All animals were dosed once only by gavage using a metal cannula attached to a graduated syringe. The volume of test material administered to each animal was calculated according to its fasted bodyweight at the time of dosing.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose:
A range finding study was performed to establish a dosing regime. Based on the results of the range-finding study a further group of animals was treated.

Doses:

Range-finding study: 5000 mg/kg
Main study: 5000 mg/kg

No. of animals per sex per dose:

Range finding study:
1 male
1 female

Main study
5 male
5 female

Control animals:

no

Details on study design:

- Duration of observation period following administration:
14 days

- Frequency of observations and weighing:
The animals were observed for deaths or overt signs of toxicity 1, 2.5 and 4 hours after dosing and subsequently once daily for 14 days.

Individual bodyweights were recorded prior to dosing on Day 0 and on Days 7 and 14.

- Necropsy of survivors performed:
At the end of the study the animals were killed by an overexposure of CO2 and subjected to gross pathological examination. This consisted of an external examination and opening of the abdominal and thoracic cavities. The appereance of any macroscopic abnormalities was recorded. No tissues were retained.

- Other examinations performed:
clinical signs and body weight

Statistics:

Data evaluations included the relationship, if any, between the animals' exposure to the test material and the incidence and severity of all abnormalities including behavioural and clinical observations, gross pathological lesions, bodyweight changes, mortality and any other toxicological effects.

Using the mortality data obtained, an estimate of the acute oral median lethal dose LD50 of the test material was made.

Results and discussion

Preliminary study:

Individual clinical observations an mortality data are given in Table 1. Individual necropsy findings are given in Table 2.

There were no deaths or clinical signs of toxicity. No abnormalities were noted at necropsy.

Based on this information, a dose level of 5000 mg/kg bodyweight was selected for the main study.

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Remarks on result:

other: 95% CL not recorded

Mortality:

Individual mortality data are given in Table 3.

There were no deaths.

Clinical signs:

Individual clinical observations are given in Table 3.

No signs of systemic toxicity were noted during the study.

Body weight:

Individual bodyweights, together with weekly bodyweight gains are given in Table 4.

All animals showed expected gain in bodyweight during the study.

Gross pathology:

Individual necropsy findings are given in Table 5.

No abnormalities were noted at necropsy.

Other findings:

No other findings recorded.

Any other information on results incl. tables

Table 1 Individual Clinical Observations and Mortality Data in the Range-Finding Study

Dose Level mg/kg	Animal Number and Sex	Effects Noted After Dosing (Hours)			Effects Noted During Period After Dosing (Days)
		1	2.5	4	1	2	3	4	5
5000	1-0 Male	0	0	0	0	0	0	0	0
	2-0 Female	0	0	0	0	0	0	0	0

Table 2 Individual Necropsy Findings in the Range-Finding Study

Dose Level mg/kg	Animal Number and Sex	Time of Death	Macrospopic Observations
5000	1-0 Male	Killed Day 5	No abnormalities detected
	2-0 Female	Killed Day 5	No abnormalities detected

Table 3 Individual Clinical Observations and Mortality Data in the Main Study

Dose Level mg/kg	Animal Number and Sex	Effects Noted After Dosing (Hours)			Effects Noted During Period After Dosing (Days)
		1	2.5	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
5000	3-0 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-1 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-2 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-3 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-4 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-0 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-1 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-2 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-3 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-4 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

Table 4 Individual Bodyweights and Weekly Bodyweight Gain in the Main Study

Dose Level mg/kg	Animal Number and Sex	Bodyweight (g) at Day			Bodyweight Gain (g) During Week
		0	7	14	1	2
5000	3-0 Male	231	304	355	73	51
	3-1 Male	219	270	304	51	34
	3-2 Male	207	276	329	69	53
	3-3 Male	234	293	333	59	40
	3-4 Male	215	280	328	65	48
	4-0 Female	202	230	250	28	20
	4-1 Female	203	225	340	22	15
	4-2 Female	219	259	276	40	17
	4-3 Female	203	215	230	12	15
	4-4 Female	206	242	261	36	19

Table 5 Individual Necropsy Findings in the Main Study

Dose Level mg/kg	Animal Number and Sex	Time of Death	Macroscopic Observations
5000	3-0 Male	Killed Day 14	No abnormalities detected
	3-1 Male	Killed Day 14	No abnormalities detected
	3-2 Male	Killed Day 14	No abnormalities detected
	3-3 Male	Killed Day 14	No abnormalities detected
	3-4 Male	Killed Day 14	No abnormalities detected
	4-0 Female	Killed Day 14	No abnormalities detected
	4-1 Female	Killed Day 14	No abnormalities detected
	4-2 Female	Killed Day 14	No abnormalities detected
	4-3 Female	Killed Day 14	No abnormalities detected
	4-4 Female	Killed Day 14	No abnormalities detected

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute oral median lethal dose (LD50) of the test material, Alkane 2, in the Sprague-Dawley strain rat was found to be greater than 5000 mg/kg bodyweight.

Executive summary:

1. A study was performed to assess the acute oral toxicity of the test material in the Sprague-Dawley strain rat.

The study was designed to comply with the requirements of the U.S Environmental Protection Agency (EPA) Guidelines, the OECD Guidelines for Testing of Chemicals No. 401 "Acute Oral Toxicity" (adopted 24 Feb 1987) and Method B1 of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC) and the Japanese Ministry of Agriculture, Forestry and Fisheries (MAFF), Testing Guidelines for Toxicological Studies, 59 NohSan No. 4200, January 28 1985.

2. Following a range-finding study, a group of ten fasted animals (five males and five females) was given a single oral dose of undiluted test material at a dose level of 5000 mg/kg bodyweight. The animals were observed for fourteen days after the day of dosing and were then killed and subjected to gross necropsy.

3. There were no deaths. No signs of systemic toxicity were noted during the study.

4. All animals showed expected gain in bodyweight during the study.

5. No abnormalities were noted at necropsy.

6. The acute oral median lethal dose (LD50) of the test material in the Sprague-Dawley strain rat was found to be greater than 5000 mg/kg bodyweight.