Bis(2,4-di-tert-butyl-6-methylphenyl)ethyl phosphate

Endpoint summary

Description of key information

- Acute oral toxicity (OECD guideline 401 & GLP): LD50 > 2000 mg/kg bw (CIBA-GEIGY Ltd., 924081, 1992)
- Acute dermal toxicity (OECD guideline 402 & GLP): LD50 > 2000 mg/kg bw (CIBA-GEIGY Ltd., 924082, 1992)

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:

1992-07-07 to 1992-09-10

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-Guideline study (OECD Guideline 401)

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

adopted on 24-Feb-1987

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

other: Tif: RAI f (SPF)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: CIBA-GEIGY Ltd.
- Age at study initiation: Young adult
- Weight at study initiation: 176 to 220 g
- Fasting period before study: Prior to dosing, the animals were fasted overnight
- Housing: Segregated by sex, group-housed (5 animals per cage) in Macrolon cages type 4, with standardized soft wood bedding
- Diet: Rat chow (NAFAG 890 Tox, NAFAG, Gossau/SG, Switzerland), ad libitum
- Water: ad libitum
- Acclimation period: At least 5 days before administration

ENVIRONMENTAL CONDITIONS
- Temperature: 22 +/- 2°C
- Humidity: 55 +/- 10%
- Air changes: 15 air changes/h
- Photoperiod: 12 hour/ day light cycle

Route of administration:

oral: gavage

Vehicle:

arachis oil

Details on oral exposure:

VEHICLE
- Amount of vehicle (if gavage): 10 ml/kg body weight

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5 rats

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Observations:
Mortality: daily/ a.m. and p.m. on working days, a.m. on weekend days
Signs and symptoms: daily for 14 days
Body weight: immediately before administration and on days 7 and 14
Necropsies: The animals were submitted to a gross necropsy at the end of the observation period.

Statistics:

From the body weights, the group means and their standard deviations were calculated.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred.

Clinical signs:

other: Piloerection, hunched posture, and dyspnea were seen, being common symptoms in acute tests. Additionally, reduced locomotor activity was observed in all animals. The animals recovered within 4 to 5 days.

Gross pathology:

No deviations from normal morphology were found.

Interpretation of results:

practically nontoxic

Remarks:

Migrated information

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1992-07-07 to 1992-09-10

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-Guideline study (OECD Guideline 402)

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

adopted on 24-Feb-1987

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

other: Tif: RAI f (SPF)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: CIBA-GEIGY Ltd.
- Age at study initiation: Young adult
- Weight at study initiation: 216 to 256 g
- Housing: Segregated by sex, group-housed (5 animals per cage) in Macrolon cages type 4, with standardized soft wood bedding
- Diet: Rat chow (NAFAG 890 Tox, NAFAG, Gossau/SG, Switzerland), ad libitum
- Water: ad libitum
- Acclimation period: At least 5 days before administration

ENVIRONMENTAL CONDITIONS
- Temperature: 22 +/- 2°C
- Humidity: 55 +/- 10%
- Air changes: 15 air changes/h
- Photoperiod: 12 hour/ day light cycle

Type of coverage:

semiocclusive

Vehicle:

arachis oil

Details on dermal exposure:

TEST SITE
- Area of exposure: Back of the rat
- % coverage: 10 % of the body surface
- Type of wrap if used: Gauze-lined semiocclusive dressing fastened around the trunk with an adhesive elastic bandage

REMOVAL OF TEST SUBSTANCE
- Washing: The skin was cleaned with lukewarm water at the end of the exposure period

- Time after start of exposure: 24 hrs

VEHICLE
- Amount(s) applied (volume): 4 mL/kg bw
- Constant volume or concentration used: yes (per kg bw)

Duration of exposure:

24 hrs

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5 rats

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Mortality: daily; Signs and symptoms: daily for 14 days; Body weight: at start and on days 7 and 14
- Necropsy of survivors performed: yes

Statistics:

From the body weights, the group means and their standard deviations were calculated.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred.

Clinical signs:

other: Piloerection was seen, being a common symptom in acute dermal tests. The animals recovered within one day.

Gross pathology:

No deviations from normal morphology were found.

Interpretation of results:

practically nontoxic

Remarks:

Migrated information

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

Acute oral toxicity

The acute oral toxicity of the test substance was assessed in GLP-compliant study following OECD guideline 401 (CIBA-GEIGY Ltd., 924081, 1992). In the limit test, a single dose of 2000 mg/kg bw in arachis oil was applied by gavage to five male and five female rats. No mortality occurred within the timeframe of the study. Piloerection, hunched posture and dyspnea were seen, being common symptoms in acute tests. Additionally, reduced locomotor activity was observed in all animals. All animals recovered within 4 to 5 days. Necropsy did not reveal any abnormalities. Overall, under the chosen test conditions, the test substance was not toxic after single oral administration: Oral LD50 > 2000 mg/kg bw

Acute dermal toxicity

As a second exposure route acute dermal toxicity was investigated (CIBA-GEIGY Ltd., 924082, 1992). In the GLP-compliant study according to OECD guideline 402, the Standard Acute Method using a single dose of 2000 mg/kg bw (vehicle: arachis oil) in a limit test was performed using five male and five female rats. No mortality occurred within the timeframe of the study. Clinical signs were limited to piloerection, a common symptom in acute dermal tests. All animals recovered within 1 day. At autopsy, no deviations from normal morphology were found. Overall, under the chosen test conditions, the test substance does not have toxic properties in case of single dermal exposure: Dermal LD50 > 2000 mg/kg bw

Acute inhalation toxicity

No data available.

Justification for selection of acute toxicity – oral endpoint
GLP-compliant guideline study

Justification for selection of acute toxicity – dermal endpoint
GLP-compliant guideline study

Justification for classification or non-classification

Dangerous Substance Directive (67/548/EEC)

The available experimental test data is reliable and suitable for the purpose of classification under Directive 67/548/EEC. Based on the data, classification for acute toxicity is not warranted under Directive 67/548/EEC.

 

Classification, Labeling, and Packaging Regulation (EC) No. 1272/2008

The available experimental test data are reliable and suitable for the purpose of classification under Regulation (EC) No.1272/2008. Based on the data, classification for acute toxicity is not warranted under Regulation (EC) No.1272/2008.