Phosphoric acid, butyl ester, sodium salt

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)

Version / remarks:

2001

Deviations:

no

GLP compliance:

yes

Test type:

fixed dose procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Dibutyl hydrogen phosphate

EC Number:

203-509-8

EC Name:

Dibutyl hydrogen phosphate

Cas Number:

107-66-4

Molecular formula:

C8H19O4P

IUPAC Name:

dibutyl hydrogen phosphate

Test material form:

liquid

Test animals

Species:

rat

Strain:

Crj: CD(SD)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Nippon Charles River (Co., Ltd.)
- Age at study initiation: 5 weeks
- Weight at study initiation: males 149 (137-153) g, females 122 (118-129) g
- Fasting period before study: from 5 pm in the evening prior to dosing (dosing time: 10.49-11.00 am)
- Housing: During the acclimation period and the pre-dosing observation period, the animals were housed, sex-segregated, in stainless steel mesh cages (276 mm wide × 426 mm deep × 200 mm high), 2-3 animals per cage, in a barrier system animal house
- Diet: ad libitum, Labo MR Stock solid feed, manufactured by Nihon Nosan Kogyo K.K., batch number 92.1 0.67
- Water: tap water
- Acclimation period: 12 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 55 ± 10
- Air changes (per hr): 10
- Photoperiod (hrs dark / hrs light): 12 / 12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: sesame oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 20 w/v %
- Amount of vehicle: 10 mL/kg bw

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: On the dosing day, general observation of symptoms and confirmation of survival was undertaken once within 1 hour of dosing, once approximately 3 hours after dosing and once approximately 6 hours after dosing. This was taken as day 0. From the following day (day 1) onwards, observation was undertaken at least once a day. Bodyweight was measured immediately before dosing (day 0), and on days 1, 3, 7 and 14.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Statistics:

not necessary

Results and discussion

Preliminary study:

In preliminary experiments undertaken to set the dose, no male or female fatalities were observed even on administration of 2000 mg/kg bw.

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

no mortality observed

Clinical signs:

other: After administration of 2000 mg/kg bw there were no male or female fatalities. On general observation of the symptoms after dosing, decreased locomotor activity, deepening respiration, eyelid ptosis, salivation, urine-stained abdomens, excretion of red ur

Gross pathology:

No abnormalities were observed visually in any of the males or females on necropsy.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The LD50 value of the test substance is > 2000 mg/kg bw.

Executive summary:

A study of the acute oral toxicity of the test item in rats was undertaken. No fatalities were observed after administration of 2000 mg/kg bw (chosen on the basis of the results of preliminary test). The symptoms of toxicity observed in males and females after dosing were as follows: there were symptoms of systemic suppression such as decreased locomotor activity, deepening respiration and eyelid ptosis. Abdomina were urine-stained and on the day after dosing inhibition of body weight increase or body weight decrease was observed. Some animals exhibited transient salivation and the excretion of red urine. There was recovery such that by 4 days after dosing none of these changes were observed anymore. Necropsy revealed no visible abnormalities of the organs. From these results it was concluded that the minimum lethal dose and thus also the LD50 is higher than 2000 mg/kg bw.