Reaction mass of lithium 3-hydroxy-2,2,4-trimethylpentanoate and lithium isobutyrate and sodium 3-hydroxy-2,2,4-trimethylpentanoate and sodium isobutyrate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

9 May 2013 to 24 May 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline and GLP compliant study with no deviations affecting study integrity

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of lithium 3-hydroxy-2,2,4-trimethylpentanoate and lithium isobutyrate and sodium 3-hydroxy-2,2,4-trimethylpentanoate and sodium isobutyrate

EC Number:

939-200-6

IUPAC Name:

Reaction mass of lithium 3-hydroxy-2,2,4-trimethylpentanoate and lithium isobutyrate and sodium 3-hydroxy-2,2,4-trimethylpentanoate and sodium isobutyrate

Constituent 2

Reference substance name:

Sodium Isobutyrate Solution

IUPAC Name:

Sodium Isobutyrate Solution

Test material form:

other: reaction mass semi-liquid solution

Details on test material:

- Name of test material (as cited in study report): Sodium Isobutyrate Solution

- Substance type:Reaction mass
- Physical state: Light yellow semi liquid
- Analytical purity: 86.5%

- Composition of test material, percentage of components: confidential information

- Purity test date: 12 April 2013
- Lot/batch No.: W195_02
- Expiration date of the lot/batch: 17 October 2013

- Storage condition of test material:room temperature

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: CRL:WI Wistar rats from Charles River Laboratories, Research Models and Services, Germany GmbH, Sandhofer Weg 7, D-97633 Sulzfeld
- Age at study initiation: 8 weeks
- Weight at study initiation: 184-199g
- Fasting period before study: Overnight prior to dosing and up to 3 hours post dosing
- Housing: Group housing, 3 per cage, in Type II polypropylene/polycarbonate cages
- Diet (e.g. ad libitum):ssniff® SM R/M "Autoclavable complete diet for rats and mice – breeding and maintenance - available ad libitum produced by ssniff Spezialdiäten GmbH, D-59494 Soest Germany
- Water (e.g. ad libitum): municapal supply tap water ad libitum
- Acclimation period: 9 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C):20.4 – 25.0 °C
- Humidity (%):35 – 70 %
- Air changes (per hr):15 – 20 air exchanges/hour
- Photoperiod (hrs dark / hrs light):12 hours daily, from 6.00 a.m. to 6.00 p.m.

IN-LIFE DATES: From: 9 May 2013 To: 24 May 2013

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Remarks:

distilled

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 mg/mL
- Amount of vehicle (if gavage): 10 mL/kg bw

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg bw

DOSAGE PREPARATION (if unusual): The formulation was freshly prepared at a concentration of 200 mg/mL and stirred continuous until dosing was completed

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose:The initial dose level was selected by the study director to be that which is most likely to produce mortality in some of the dosed animals. In the lack of any preliminary toxicological information, 2000 mg/kg bw was selected to be the starting dose. an initial group of three females was treated at this dose followed by a second group of three females similarly dosed.

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

3 females per group, two groups treated.

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Daily observations and weekly bodyweight recording. Additional clinical observations recorded on Day 1, 30 mins, 1, 2, 3, 4 and 6 hours post administration
- Necropsy of survivors performed: yes

Statistics:

Not applicable for a limit test

Results and discussion

Preliminary study:

Not applicable

Effect levels

Sex:

male/female

Dose descriptor:

approximate LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: Based on the acute Toxic Class Method, the median lethal dose was estimated to exceed the highest dose level administered, in the absence of any mortality or signs of toxicity at 2000 mg/kg bw

Mortality:

There were no deaths in either group dosed at 2000 mg/kg bw

Clinical signs:

other: Clinical signs of treatment were observed on Day 1 only - 3/6 rats showed decreased activity; 5/6 developed a hunched back and 2/6 had evidence of pilo-erection but all animals were overtly symptom free within 24 hours of dose administration

Gross pathology:

No macroscopic abnormalities were observed during necropsy of all surviving rats at termination on Day 14

Other findings:

No other findings

Any other information on results incl. tables

Bodyweights

Group	Animal Number	Bodyweight (g) on Day				Bodyweight gain (g)
		-1	0	7	14	-1 to 0	0 to 7	7 to 14	overall
1	1137	214	199	232	247	-15	33	15	33
	1138	210	197	237	243	-13	40	6	33
	1139	212	192	214	250	-20	22	36	38
2	1140	200	184	209	222	-16	25	13	22
	1141	195	186	213	223	-9	27	10	28
	1142	211	194	232	253	-17	38	21	42
Mean		207.0	192.0	222.8	239.7	-15.0	30.8	16.8	32.7

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information LD50 greater than 2000 mg/kg bw Criteria used for interpretation of results: EU

Conclusions:

The acute oral LD50 in rats for Sodium Isobutyrate Solution was found to exceed 2000 mg/kg bw in female CRL:(WI) rats.
The study result triggers no classification/labelling according to Regulation (EC) No 1272/2008 (CLP).

Executive summary:

The acute oral toxicity of sodium isobutyrate solution was assessed according to the acute toxic class method (OECD 423 and Commission Regulation (EC) No 440/2008 of 30 May 2008, B.1.Tris) in two groups of female CRL:(WI) rats treated at a dose level of 2000 mg/kg bw. Initially, three females were treated at 2000 mg/kg bw and, as no mortality was observed, a confirmatory group was treated at the same dose level. No mortality was observed in the confirmatory group, therefore no further testing was required according to OECD 423 and Commission Regulation (EC) NO 440/2008 of 30 May 2008, B.1.Tris.

Rats were given a single oral treatment by gavage following overnight fasting. Sodium isobutyrate solution was

formulated in distilled water at a concentration of 200 mg/mL and was dosed in a volume of 10 mL/kg bw. Clinical observations were performed at 30 minutes, 1, 2, 3, 4 and 6 hours after dosing and daily for 14 days thereafter. Body weights were measured on Days -1, 0 and 7 and before necropsy. All animals were subjected to a necropsy and a macroscopic examination. There were no mortalities among the six rats dosed at 2000 mg/kg bw. Various clinical signs were observed on day 1 only - decreased activity affecting 3 rats, hunched back (5 rats) and piloerection (2 rats). All were symptom free within 24 hours of dosing. Bodyweight gains showed no effects of treatment. No macroscopic abnormalities were apparent during necropsy. The acute oral LD50, estimated using the Acute Toxic Class method, was greater than 2000 mg/kg bw and no classification is required for oral toxicity.