Isooctyldinitrophenol

Endpoint summary

Description of key information

ORAL
- LD50 = 122 mg/kg, mouse (male), equivalent/similar to OECD 401, DeCrescente (1982)
- LD50 = 96 mg/kg, mouse (female), equivalent/similar to OECD 401, DeCrescente (1982)
- LD50 = 0.285 ± 0.005 cc/kg, rat (male), no guideline followed, Haag (1954)
DERMAL
- LD50 = in excess of 200 mg/kg, Section 191.10 of the Final Order, Enforcement Regulations, Federal Register, Vol. 26, No. 155, P. 7336, 12 August 1961, Shalanski & Moldovan (1969)
- LD50 = 1.33 ± 0.60 cc/kg, rabbit (male), no guideline followed, Haag (1954)

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

96 mg/kg bw

Quality of whole database:

The quality of the database is considered to be sufficient; two studies have been assigned a reliability score of 2, whereas one study cannot be assigned a reliability score other than 4 as limited information on materials and methods is provided.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

200 mg/kg bw

Quality of whole database:

A high quality database is not available for this endpoint; it was not possible to assign either of the two available studies a reliability score other than 4 as limited information on materials and methods are provided. However the available data is sufficient to address this endpoint for this type of registration.

Additional information

Oral

This endpoint has been addressed with three studies in a weight of evidence approach.

 

The first study, DeCrescente (1982) investigated the acute oral toxicity of the test material in which groups of 10 male CD-1 mice were administered a suspension of test material in corn oil at 0 (vehicle control), 60, 75, 95, 119, or 150 mg/kg bw, orally, via gavage. The mice were observed over a period of 14 days for mortality and clinical signs; body weights were recorded at study initiation and again at termination (group average). All animals were subjected to gross necropsy at termination.

The study was conducted to sound scientific principles and so was assigned a reliability score of 2 in line with the principles for assessing data quality as defined by Klimisch et al. (1997).

Under the conditions of the study, the acute oral LD50 was determined to be 122 mg/kg to male CD-1 mice.

 

The second study, DeCrescente (1982) investigated the acute oral toxicity of the test material in a study in which groups of 10 female CD-1 mice were administered a suspension of test material in corn oil at 0 (vehicle control), 60, 75, 95, 119, or 150 mg/kg bw, orally, via gavage. The mice were observed over a period of 14 days for mortality and clinical signs; body weights were recorded at study initiation (group average) and at termination (in one animal). All animals were subjected to gross necropsy at termination. The study was conducted to sound scientific principles and so was assigned a reliability score of 2 in line with the principles for assessing data quality as defined by Klimisch et al. (1997).

Under the conditions of the study, the acute oral LD50 was determined to be 96 mg/kg to female CD-1 mice.

 

The third study, Haag (1954) contained limited information on materials and methods; it is therefore not possible to assess the reliability of the relevant results.

Groups of 10 fasted male rats were administered a suspension of test material in corn oil orally, by gavage, at doses of 0.25, 0.30 or 0.34 cc/kg. Mortality was recorded.

Under the conditions of the study, the LD50 of the test material to male rats was reported to be 0.285 ± 0.005 cc/kg.

 

Dermal

This endpoint has been addressed with two studies in a weight of evidence approach.

 

The first study, Shalanski & Moldovan (1969), was performed on 10 albino rabbits according to the method described under Section 191.10 of the Final Order, Enforcement Regulations, Federal Register, Vol. 26, No. 155, P. 7336, 12 August 1961.

During the study 10 rabbits received 200 mg/kg test material to a site of intact skin. None of the animals died during the study.

There is limited information on materials and methods within this study; it is therefore not possible to assess the reliability of the relevant results.

The acute dermal LD50 was therefore reported to be in excess of 200 mg/kg.

Although the LD50 value was determined to be above 200 mg/kg, it is not possible to determine that the LD50 value does not fall into Category 3 with the data that is available. Therefore this classification has been applied on a precautionary basis.

 

The second study, Haag (1954) contains limited information on materials and methods within this study; it is therefore not possible to assess the reliability of the relevant results.

Within this study, Groups of young male rabbits were clipped free of hair and topically administered test material at 0.5, 1.0, 1.5, 2.0, 2.5, or 3.0 and above cc/kg. Mortality was recorded.

Under the conditions of the study, the LD50 of the test material was reported to be 1.33 ± 0.60 cc/kg.

Justification for selection of acute toxicity – oral endpoint
No study has been selected as key; this endpoint has been addressed via a weight of evidence approach using three studies.

Justification for selection of acute toxicity – dermal endpoint
No study has been selected as key; this endpoint has been addressed via a weight of evidence approach using two studies.

Justification for classification or non-classification

In accordance with the criteria for classification as defined in Annex I, Regulation (EC) No. 1272/2008, substance requires classification with respect to acute (oral) toxicity as Category 3 (H301: Toxic if swallowed).

In accordance with the criteria for classification as defined in Annex I, Regulation (EC) No. 1272/2008, substance requires classification with respect to acute (dermal) toxicity as Category 3 (H311: Toxic in contact with skin).