2,5-di-tert-pentylhydroquinone

Endpoint summary

Description of key information

Acute oral toxicity of 2,5-Di-t-pentylhydroquinone was tested in one study with male and female rats. In addition, acute dermal toxicity of 2,5-Di-t-pentylhydroquinone was tested in one study with male and female rabbits.

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:

1974

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study is not performed under GLP conditions, used methods and results are preliminary documented.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline followed

Principles of method if other than guideline:

Rats were administered 1260, 1580, 2000, 2510, 3160 mg/kg bw Santovar A in corn oil as single oral dose and were observed for 14 days.

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

no information provided

Route of administration:

oral: unspecified

Vehicle:

corn oil

Doses:

1260, 1580, 2000, 2510, 3160 mg/kg bw Santovar A

No. of animals per sex per dose:

3 or 2

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Other examinations performed: clinical signs, body weight

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

1 900 mg/kg bw

95% CL:

> 1 800 - < 2 000

Mortality:

Yes

Clinical signs:

other: Reduced appetite and activity, increasing weakness, collapse, and death.

Gross pathology:

Hemorrahagic areas of the lungs, slight liver hyperemia, and acute gastrointestinal inflammation.

Other findings:

none

Interpretation of results:

sligthly toxic

Remarks:

Migrated information Criteria used for interpretation of results: not specified

Conclusions:

A study in rats suggested that Santovar was slightly toxic, an oral LD50 of 1900 mg/kg bw was reported. The study was not performed according to the general guidelines for acute oral toxicity under GLP conditions and was very poorly documented. Therefore, the information may be considered reliable with major restrictions.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

1 900 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:

1974

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study is not performed under GLP conditions, used methods and results are preliminary documented.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline followed

Principles of method if other than guideline:

Rats were exposed to 2000, 3160, 5010, 7940 mg/kg bw Santovar A in corn oil during 24 hours and were observed for 14 days.

GLP compliance:

not specified

Test type:

standard acute method

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Type of coverage:

not specified

Vehicle:

corn oil

Duration of exposure:

24 hours

Doses:

2000, 3160, 5010, 7940 mg/kg bw Santovar A

No. of animals per sex per dose:

1 or 2 at highest dose

Control animals:

no

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 3 160 mg/kg bw

Mortality:

Yes, at 5010 and 7940 mg/kg bw after 4 and 5 days, resp.

Clinical signs:

other: Reduced appetite and activity, increasing weakness, collapse, and death.

Gross pathology:

Lung and liver hyperemia, enlarged gall bladder, and gastrointestinal inflammation.

Other findings:

none

Interpretation of results:

sligthly toxic

Remarks:

Migrated information Criteria used for interpretation of results: not specified

Executive summary:

A study in rabbits suggested that Santovar was slightly toxic, a dermal LD50 of > 3160 mg/kg bw was reported. The study was not performed according to the general guidelines for dermal toxicity under GLP conditions and was very poorly documented. Therefore, the information may be considered reliable with major restrictions.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

3 160 mg/kg bw

Additional information

The studies were not performed according to the general guidelines for acute oral/dermal toxicity testing neither performed under GLP-conditions and were documented poorly. Therefore, the data should be considered as indicative only. Upon oral administration of 2,5-Di-t-pentylhydroquinone to rats an LD50 of 1900 mg/kg bw is reported and upon dermal administration of 2,5-Di-t-pentylhydroquinone to rabbits an LD50 of > 3160 mg/kg bw is reported.

Justification for classification or non-classification

Based on the above mentioned results, the substance shall be classified for acute toxicity with R22 according to Dangerous Substance Directive 67/548/EC and Acute tox 4 according to CLP Regulation (EC) 1272/2008.