Dimethoxymethyloctadecylsilane

Endpoint summary

Description of key information

Oral (OECD 423), rat: LD50 >2000 mg/kg bw

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13 May - 12 Sep 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Freie und Hansestadt Hamburg, Behörde für Arbeit, Gesundheit uns SozialesFreie und Hansestadt Hamburg, Behörde für Arbeit, Gesundheit uns Soziales, Germany

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

other: Crl:CD

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: 42 (males) or 53 (females) days
- Weight at study initiation: 215 - 230 g (males); 206 - 231 g (females)
- Fasting period before study: yes (16 h before administration)
- Housing: 2-3 animals per cage during the 14-day observation period (MAKROLON cages, type III).
- Diet: ssniff/R/M-H V 1530 (ssniff Spezialdiäten GmbH, Soest, Germany), ad libitum
- Water: tap water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±3
- Humidity (%): 55±15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 13 May 2002 To : 02 Jul 2002

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 2.35 ml/kg bw

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

First step: 3 males
Second step: 3 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observations were performed before and immediately, at 5, 15, 30 and 60 min, as well as at 3, 6 and 24 hours after administration. All surviving animals were observed for a period of 14 days (once daily). Body weight was determined before administration and weekly thereafter.
- Necropsy of survivors performed: yes
- Other examinations performed: Changes of skin and fur, eyes and mucous membranes, respiratory and circulatory, autonomic and central nervous system, somatomotor activity and behaviour pattern were observed at least once daily until all symptoms subsided (afterwards each working day).

Statistics:

No statistical analysis was performed

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred.

Clinical signs:

No clinical signs of toxicity were observed.

Body weight:

All surviving animals gained the expected body weight.

Gross pathology:

No abnormalities were observed.

Table 1: Body weights, body weight gain and autopsy findings of the surviving rats.

Body weights (body weight gain) [g]	Dose, oral gavage: 2000 mg/kg bw
	male	female
start	225.0	216.3
after 7 days	283.0 (+25.7)	240.3 (+11.1)
after 14 days	308.3 (+37.0)	249.3 (+15.3)
Inhibition of body weight gain	none	none
Autopsy finding	none	none
Mortality	0/3	0/3

Interpretation of results:

other: CLP/EU GHS criteria are not met, no classification required according to Regulations (EC) No 1272/2008

Conclusions:

In an acute oral toxicity study conducted according to OECD 423 and in compliance with GLP, a LD50 >2000 mg/kg bw was observed in rats. No mortality and no clinical signs were observed. No effects on body weight gain and no abnormalities at necropsy were reported.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The available information comprises an adequate and reliable study (Klimisch score 1), and is thus sufficient to fulfil the standard information requirements set out in Annex VII, 8.6, of Regulation (EC) No 1907/2006.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

A key study is available with dimethoxymethyloctadecylsilane (CAS 70851-50-2), which was conducted according to OECD 423 and in compliance with GLP (LPT, 2002). In a first step 3 male Crl:CD rats were treated with the limit dose of 2000 mg/kg bw. No mortality and no clinical signs were observed. In accordance with the testing strategy supplied in OECD guideline 423, 3 female animals were treated with the limit dose of 2000 mg/kg bw. Again, no mortality and no clinical signs were observed. No findings after necropsy and no effects on body weight were observed in any animal. In conclusion, a LD50 >2000 mg/kg bw was derived for dimethoxymethyloctadecylsilane after oral treatment.

Justification for classification or non-classification

The available data on acute oral toxicity of the registered substance do not meet the criteria for classification according to Regulation (EC) 1272/2008 and according to Directive 67/548/EEC, and are therefore conclusive but not sufficient for classification.

No data on acute dermal and inhalation toxicity are available.