Trichloro(2,4,4-trimethylpentyl)silane

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 7 May to 28 June 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted largely in accordance with the OECD guideline and with GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

doses not as recommended in OECD 423 (2001)

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Trichloro(2,4,4-trimethylpentyl)silane

EC Number:

242-262-0

EC Name:

Trichloro(2,4,4-trimethylpentyl)silane

Cas Number:

18379-25-4

Molecular formula:

C8H17Cl3Si

IUPAC Name:

trichloro(2,4,4-trimethylpentyl)silane

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 Deutschland GmbH, Sulzfeld, GERMANY
- Age at study initiation: 41 days (males), 48 days (females)
- Weight at study initiation: 179-215 g(males), 175-210 g (females)
- Fasting period before study: 16 h
- Housing: 2-3/Makrolon type III cage
- Diet: standard diet ad libitum
- Water: drinking water ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3
- Humidity (%): 55 +/- 15
- Air changes (per hr): no details
- Photoperiod (hrs dark / hrs light): 12 h/12 h

IN-LIFE DATES: 5 cycles (each of 1 day treatment and 14 days observation) overlapping in some cases From: 2002-05-07 To: 2002-06-28

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: neat at 2000 mg/kg bw; in corn oil at 200 and 25 mg/kg bw

Details on oral exposure:

VEHICLE
used for 200 and 25 mg/kg bw doses only
- Justification for choice of vehicle: not given
- Lot/batch no. (if required): 81K2204
- Purity: not stated

MAXIMUM DOSE VOLUME APPLIED: 1.87 ml/kg bw in all cases

DOSAGE PREPARATION (if unusual): not given

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: not given
Starting dose 2000 mg/kg bw. The subsequent doses of 200 and 25 mg/kg bw are not as recommended in OECD 423 or the equivalent EC guideline L248: B.1 tris. Also, it is not clear why testing at the mid-dose was repeated in a second sex

Doses:

2000, 200 and 25 mg/kg bw

No. of animals per sex per dose:

2000 mg/kg bw 3 males
200 mg/kg bw 3 males followed by 3 females
25 mg/kg bw 3 males followed by 3 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: 6 observations on day 1, then daily observations and weekly weighings
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Statistics:

None.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 25 - < 200 mg/kg bw

Mortality:

All males died at 2000 mg/kg bw and 2/3 died at 200 mg/kg bw. No females died at 200 mg/kg bw and no animals died at 25 mg/kg bw. (See also table 1.)

Clinical signs:

other: Slight to moderate reduced motiltiy, ataxia and dyspnoea, slightly reduced muscle tone or adopting a lateral or abdominal postition were noted in all animals of the 2000 mg/kg bw group. No clinical signs were noted in any other dose group. (See also table

Gross pathology:

No abnormalities were reported.

Other findings:

None

Any other information on results incl. tables

Table 1: Number of animals dead or with evident toxicity

Dose (mg/kg bw)	Mortality (dead/total)			Time range of deaths	Number with evident toxicity
	Male	Female	Combined		Male	Female
2000	3/3	-	3/3	1h, 1h, 24h*	3/3 reduced motility and ataxia; 2/3 reduced muscle tone, dyspnoea, prone position	-
200	2/3	0/3	2/6	1 day, 7 days	3/3 no clinical signs	3/3 no clinical signs
25	0/3	0/3	0/6	-	3/3 no clinical signs	3/3 no clinical signs

 * sacrificed as moribund

Applicant's summary and conclusion

Interpretation of results:

Toxicity Category III

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

A reliable study conducted very largely in compliance with the standard guideline and in accordance with GLP, identified an LD50 in the range 25-200 mg/kg bw in male and female rats. There was no evidence of toxicity at the lowest tested dose of 25 mg/kg bw.