[No public or meaningful name is available]

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2021

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Test material

Test material information

Constituent 1

Reference substance name:

Tributyl(ethyl)phosphonium diphenyl phosphate

Cas Number:

2409816-82-4

Molecular formula:

C26H42O4P2

IUPAC Name:

Tributyl(ethyl)phosphonium diphenyl phosphate

Test material form:

liquid

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

Age at First Dose: 8 - 12 weeks; female animals were non-pregnant and nulliparous
The health condition of animals was examined by a veterinarian before initiation of the study.
The animals were acclimated to the condition identical to the condition during the experiment at least 5 days prior to the start of treatment. The acclimation was according to standard operation procedures.
The animals were housed in plastic cages suspended on stainless steel racks, up to 3 animals per cage, in a room equipped with central airconditioning. The room temperature was maintained within the range of 22±2 °C. The relative humidity will be 55±10 %. The light regime was set to a 12-hour light / 12-hour dark cycle. The sanitation was performed according to standard operation procedures.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

olive oil

Doses:

The starting dose can be selected from the fixed dose levels of 5, 50, 300, and 2000 mg/kg body weight. Available information indicated that the test item was likely to be non-toxic regarding acute toxicity therefore we chose a dose of 2000 mg of Tributyl(ethyl)phosphonium diphenyl phosphate per kg body weight to be used as a starting dose. In the first step, one group of 3 females was dosed. The test item in limit dose caused mortality in all 3 females. Therefore we continued with a lower dose of 300 mg/kg. The test item in this dose did not cause mortality for 48 hours and therefore, in a third step, another 3 females were treated at the same dose level.

No. of animals per sex per dose:

The starting dose can be selected from the fixed dose levels of 5, 50, 300, and 2000 mg/kg body weight. Available information indicated that the test item was likely to be non-toxic regarding acute toxicity therefore we chose a dose of 2000 mg of Tributyl(ethyl)phosphonium diphenyl phosphate per kg body weight to be used as a starting dose. In the first step, one group of 3 females was dosed. The test item in limit dose caused mortality in all 3 females. Therefore we continued with a lower dose of 300 mg/kg. The test item in this dose did not cause mortality for 48 hours and therefore, in a third step, another 3 females were treated at the same dose level.

Results and discussion

Preliminary study:

Mortality of 3/3 females at limit dose of 2000 mg/kg body weight was observed.
All six female animals survived after administration at the dose of 300 mg/kg body weight. No signs of intoxication, change of health, nor any other adverse reactions during 24 hours and 14-days observation period at this dose was observed.

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - < 2 000 mg/kg bw

Mortality:

Mortality of 3/3 females at limit dose of 2000 mg/kg body weight was observed.
All six female animals survived after administration at the dose of 300 mg/kg body weight. No signs of intoxication, change of health, nor any other adverse reactions during 24 hours and 14-days observation period at this dose was observed.

Clinical signs:

other: Mortality of 3/3 females at limit dose of 2000 mg/kg body weight was observed. All six female animals survived after administration at the dose of 300 mg/kg body weight. No signs of intoxication, change of health, nor any other adverse reactions during 24

Gross pathology:

No visible pathological findings were observed in all animals.

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

LD50 of the test item “Tributyl(ethyl)phosphonium diphenyl phosphate” is greater than 300 mg/kg body weight and lower than 2000 mg/kg body weight after single oral administration to Wistar rats.

Executive summary:

Based on Annex 2d Test Procedure with a Starting Dose of 2000 mg/kg body weight of OECD Guideline 423 it can be concluded that the test item “Tributyl(ethyl)phosphonium diphenyl phosphate” is classified in GHS Category 4 with a LD50 cut off value 500 mg/kg body weight, after single oral administration to Wistar rats.