Dibutyl hydrogen phosphate

Endpoint summary

Description of key information

A valid oral toxicity study according OECD 401 is available that shows an LD50 of > 2000 mg/kg bw.
In a valid in-vitro corrosion test according OECD TG 431, dibutyl hydrogen phosphate was corrosive. Therefore an acute inhalation and dermal toxicity study does not need to be conducted according REACH Annex VII column 2.

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: scientifically acceptable and sufficient documented

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Principles of method if other than guideline:

5 male and 5 female rats were administered a single dose of dibutyl hydrogen phosphate per gavage. Animals were observed for mortality, body weight and clinical signs. A gross necropsy was performed on animals sacrificed at the end of the study.

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

other: Crj:CD(SD)

Sex:

male/female

Route of administration:

oral: gavage

Vehicle:

not specified

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5 males and 5 females/dose

Control animals:

no

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: No deaths occurred

Mortality:

none

Clinical signs:

other: During the course of the study, a decrease in locomotor activity, deep and slow respiration, blepharoptosis and blotted fur with urine on the lower abdomen were observed in males and females, and lacrimation and red urine were additionally observed in som

Gross pathology:

No macroscopic abnormalities were seen in pathological examination for both male and female groups.

Interpretation of results:

GHS criteria not met

Conclusions:

LD50 > 2000 mg/kg bw (rats, male and female).

Executive summary:

Five male and five female rats were administered a single dose of dibutyl hydrogen phosphate per gavage. Animals were observed for mortality, body weight and clinical signs. A gross necropsy was performed on animals sacrificed at the end of the study.

During the course of the study, a decrease in locomotor activity, deep and slow respiration, blepharotosis and blotted fur with urine on the lower abdomen were observed in males and females, and lacrimation and red urine were additionally observed in some rats.

Body weight gain was slightly suppressed on the following day of treatment in many rats. No deaths occurred, and no macroscopic abnormalities were seen in pathological examination for both male and female groups.

LD50 > 2000 mg/kg bw (rats, male and female)

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Quality of whole database:

The materials/methods and results are described in detail und are sufficient for evaluation.

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

In the oral toxicity key study of dibutyl hydrogen phosphate 5 male and 5 female rats were administered a single dose of 2000 mg/kg bw per gavage (OECD TG 401). Animals were observed for mortality, body weight and clinical signs. A gross necropsy was performed on animals sacrificed at the end of the study.

No deaths occurred, and no macroscopic abnormalities were seen in pathological examination for both male and female groups.

In the acute oral toxicity study from a secondary source, in rats the oral LD50 is > 3200 mg/kg bw.

No acute inhalation and dermal toxicity study was conducted for animals welfare reasons, because dibutyl hydrogen phosphate is corrosive according to a valid in-vitro corrosion test following OECD 431.

 

Justification for classification or non-classification

In the acute oral toxicity study an oral LD50 > 2000 mg/kg bw (discriminating dose) was found.

No acute inhalation and dermal toxicity study was conducted for animals welfare reasons, because dibutyl hydrogen phosphate is corrosive according a valid in-vitro corrosion test following OECD 431.

According to CLP classification criteria (Regulation (EC) No 1272/2008) a classification is not justified.