RSS-4, DRY SUBSTANCE

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2008/11/11-2008/12/10

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:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

UK GLP standards (Schedule 1, Good Laboratory Practice Regulations 1999 (SI 1999/3106 as amended by SI 2004/0994)).

Test type:

fixed dose procedure

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

421-140-2

EC Name:

-

Molecular formula:

C12H22O4Mg

IUPAC Name:

magnesium(2+) bis(2-ethylbutanoate)

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source:
Harlan Laboratories UK Ltd., Bicester, Oxon, Uk.
- Age at study initiation:
8-12 weeks.
- Weight at study initiation:
156-173g
- Fasting period before study:
Overnight
- Housing:
suspended solid-floor polypropylene cages furnished with wood flakes.
- Diet (e.g. ad libitum):
Ad libitum, apart from overnight period of fasting before initiation of study and approximately 3-4 hours after dosing.
- Water (e.g. ad libitum):
Ad libitum, apart from overnight period of fasting before initiation of study and approximately 3-4 hours after dosing.
- Acclimation period:
At least 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C):
19-25 deg C
- Humidity (%):
70%
- Air changes (per hr):
15 changes per hour
- Photoperiod (hrs dark / hrs light):
12 hours dark/12 hours light


IN-LIFE DATES: From: Day 1 To: Day 14

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

arachis oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle:
300mg/kg dose level: 30 mg/ml
2000mg/kg dose test: 200 mg/ml
- Amount of vehicle (if gavage):
300mg/kg dose level: 10 mg/kg
2000mg/kg dose test: 10 mg/kg
- Justification for choice of vehicle:
Arachia Oil BP was used because the test material did not dissolve/suspend in distilled water.
- Lot/batch no. (if required):
CTO-35
- Purity:
Not stated.


MAXIMUM DOSE VOLUME APPLIED:
200mg/kg

DOSAGE PREPARATION (if unusual):
Not applicable.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose:
In the absence of data regarding the toxicity of the test material, 300 mg/kg was chosen as the starting dose.

Doses:

300mg/kg
2000mg/kg

No. of animals per sex per dose:

300mg/kg dose: 1 female
2000mg/kg dose: 5 female

Control animals:

no

Details on study design:

- Duration of observation period following administration:
14 days
- Frequency of observations and weighing:
daily
- Necropsy of survivors performed:
Yes
- Other examinations performed:
clinical signs, body weight, organ weights, histopathology, behavoural abservations.

Statistics:

Not applicable.

Results and discussion

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

-300 mg/kg bw group:
There was no mortality.

-2000 mg/kg bw group:
One animal treated was killed in extremis one day after dosing.

Clinical signs:

other: -300 mg/kg bw group: Signs of systemic toxicity noted during the day of dosing were hunched posture and pilo erection. The animal appeared normal four hours after dosing. -2000 mg/kg bw group: Signs of systemic toxicity noted were hunched posture, pilo-e

Gross pathology:

-300mg/kg bw group:
Necropsy findings are given in Table 3.
No abnormalities were noted at necropsy.

-2000 mg/kg bw group:
Individual necropsy findings are given in Table 6.
Abnormalities noted at necropsy of the animal that was killed in extremis were abnormally red lungs, dark liver and dark kidneys. No abnormalities were noted at necropsy of animals that were killed at the end of the study.

Other findings:

- Organ weights:
No abnormalities deteched.
- Histopathology:
Not stated.
- Potential target organs:
Not stated.
- Other observations:
Not stated.

Any other information on results incl. tables

Table1              Individual Clinical Observations and Mortality Data -300mg/kg

Dose Level mg/kg	Animal Number and Sex	Effects Noted After Dosing (Hours)				Effects Noted During Period After Dosing (Days)
		½	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
300	1-0 Female	HP	HP	HP	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

0= No signs of systemic toxicity

H = Hunched posture

P = Pilo-erection

Table2              Individual Bodyweights and Bodyweight Changes -300mg/kg

Dose Level mg/kg	Animal Number and Sex	Bodyweight (g) at Day			Bodyweight Gain (g) During Week
		0	7	14	1	2
300	1-0 Female	170	188	198	18	10

Table3              Necropsy Findings -300 mg/kg

Dose Level mg/kg	Animal Number and Sex	Time of Death	Macroscopic Observations
300	1-0 Female	Killed Day 14	No abnormalities detected

Table4              Individual Clinical Observations and Mortality Data -2000mg/kg

Dose Level mg/kg	Animal Number and Sex	Effects Noted After Dosing (Hours)				Effects Noted During Period After Dosing (Days)
		½	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	2-0 Female	0	0	HLARl	HLARlWt	HARl	H	0	0	0	0	0	0	0	0	0	0	0	0
	3-0 Female	H	HLA	HLAP	HLAP	HLAPRd	HPRd	H	H	0	0	0	0	0	0	0	0	0	0
	3-1 Female	H	HLA	HLAP	HLAP	HLAPRd (RrHoDh)X*
	3-2 Female	H	HLA	HLAP	HLAP	HP	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-3 Female	H	HLA	HLAP	HLAP	H	0	0	0	0	0	0	0	0	0	0	0	0	0

0= No signs of systemic toxicity

H = Hunched posture

P = Pilo-erection

L = Lethargy

A = Ataxia

Rd = Decreased respiratory rate

Rl = Laboured respiration

Wt = Tiptoe gait

Rr = Loss of righting reflex

Ho = Hypothermia

Dh = Dehydration

( ) = Observations noted prior to killingin extremis

X* = Animal killedin extremis

Table5              Individual Bodyweights and Bodyweight Changes-2000mg/kg

Dose Level mg/kg	Animal Number and Sex	Bodyweight (g) at Day			Bodyweight (g) at Death	Bodyweight Gain (g) During Week
		0	7	14		1	2
2000	2-0 Female	168	170	184		2	14
	3-0 Female	160	167	179		7	12
	3-1 Female	173	-	-	162	-	-
	3-2 Female	159	176	180		17	4
	3-3 Female	156	166	183		10	17

Table6              Individual Necropsy Findings-2000mg/kg

Dose Level mg/kg	Animal Number and Sex	Time of Death	Macroscopic Observations
2000	2-0 Female	Killed Day 14	No abnormalities detected
	3-0 Female	Killed Day 14	No abnormalities detected
	3-1 Female	Killedinextremis Day 1	Lungs: abnormally red Liver: dark Kidneys: dark
	3-2 Female	Killed Day 14	No abnormalities detected
	3-3 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 in the female Wistar strain rat was estimated to be greater than 2000 mg/kg bodyweight (Globally Harmonised Classification System - Category 5).

Executive summary:

Introduction. 

The study was performed to assess the acute oral toxicity of the test material in the Wistar strain rat. The method was designed to meet the requirements of the following:

§        OECD Guidelines for Testing of Chemicals No 420 “Acute Oral Toxicity - Fixed Dose Method” (2001)

§        Method B1bisAcute Toxicity (Oral) of Commission Directive 2004/73/EC

Method. 

Following a sighting test at dose levels of300 mg/kg and2000 mg/kg, a further group of four fasted females was given a single oral dose of test material, as asuspensioninarachis oil BP, at a dose level of2000 mg/kg bodyweight. Clinical signs and bodyweight development were monitored during the study. All animals were subjected to gross necropsy.

Mortality.

One animal treated at a dose level of 2000 mg/kg was killedin extremisone day after dosing. There were no deaths noted at a dose level of 300 mg/kg.

Clinical Observations.

Signs of systemic toxicity noted in both dose groups were hunched posture and pilo-erection. Additional signs of systemic toxicity noted in animals treated at a dose level of 2000 mg/kg were lethargy, ataxia, decreased respiratory rate, laboured respiration, tiptoe gait, loss of righting reflex, hypothermia and dehydration. Surviving animals appeared normal four hours or two to five days after dosing.

Bodyweight.

Surviving animals showed expected gains in bodyweight.

Necropsy. 

Abnormalities noted at necropsy of the animal that was killedin extremiswere abnormally red lungs, dark liver and dark kidneys. No abnormalities were noted at necropsy of animals that were killed at the end of the study.

Conclusion. The acute oral median lethal dose (LD₅₀) of the test material in the female Wistar strain rat was estimated to be greater than 2000 mg/kg bodyweight (Globally Harmonised Classification System-Category 5).