Reaction mass of methyl dihydrogen phosphate and orthophosphoric acid and dimethyl hydrogen phosphate

Endpoint summary

Description of key information

Acute toxicity after single oral application was tested in female rats, which received up to 6647 mg/kg bw. Three females out of ten died at 1688 mg/kg bw, 4 at 2638 mg/kg bw, and all animals at 4220 mg/kg bw and above. The LD50 value for acute oral toxicity was calculated to be 2690 mg/kg bw.

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:

weight of evidence

Study period:

Apr 1968

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study design similar to OECD 401 with deviations and restricted reporting

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

7 days recovery, females tested

GLP compliance:

no

Remarks:

performed before GLP

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 99.6 g (mean)
- Fasting period before study: 12 h
- Diet (e.g. ad libitum): Standard Altorim R (Altromin GmbH, Lage/Lippe, Germany), ad libitum
- Water (e.g. ad libitum): tap water, ad libitum

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 10%

Doses:

1.0; 1.6; 2.5; 4.0 or 6.3 mL/100 g bw
according to
1055; 1688; 2638; 4200 or 6647 mg/kg bw ((assuming a density of 1.055 g/cm3 in case of a 10% solution)

No. of animals per sex per dose:

10 females/dose

Control animals:

no

Details on study design:

- Duration of observation period following administration: 7 days

Statistics:

LD50 derivation according Kärber method

Sex:

female

Dose descriptor:

LD50

Effect level:

2.55 other: (10% solution)/100 g bw

Remarks on result:

other: corresponding to 2690 mg/kg bw/d

Mortality:

Dose: 1055 mg/kg bw; Mortality rate: 0/10
Dose: 1688 mg/kg bw, Mortality rate: 3 / 10
Dose: 2638 mg/kg bw, Mortality rate: 4 / 10
Dose: 4220 mg/kg bw, Mortality rate: 10 / 10
Dose: 6647 mg/kg bw, Mortality rate: 10 / 10

Clinical signs:

other: no data

Gross pathology:

no data

Other findings:

no data

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The median lethal dose of the testsubstance was 2690 mg per kg body weight. Based on the result of this study the test substance is not subject for labelling and classification requirements according to regulatory requirements.

Executive summary:

The test item was tested for its acute oral toxicity potential. 10 female rats were treated with doses of 1055, 1688, 2638, 4220 or 6647 mg/kg bw and observed for 7 days.

The median lethal dose was 2690 mg per kg body weight. Based on the result of this study the test substance is not subject for labelling and classification requirements according to regulatory requirements.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 690 mg/kg bw

Quality of whole database:

2 (reliable with restrictions)

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no study available

Quality of whole database:

n.a.

Additional information

Based on the results of an oral toxicity study the LD₅₀value for acute oral toxicity was calculated to be 2690 mg/kg bw.
According to EU regulation 1907/2006, Annex VII, column 2 an acute dermal or inhalation toxicity study needs not to be conducted sincereaction mass of Methyl dihydrogen phosphate and Orthophosphoric acid and Dimethyl hydrogen phosphateis classified as corrosive to the skin.

Justification for selection of acute toxicity – oral endpoint
Study design similar to OECD 401 with deviations and restricted reporting

Justification for selection of acute toxicity – inhalation endpoint
n.a.

Justification for classification or non-classification

Due to the findings described in the acute oral toxicity study (LD50 oral in rats 2690 mg/kg bw)reaction mass of Methyl dihydrogen phosphate and Orthophosphoric acid and Dimethyl hydrogen phosphatedoes not have to be classified as acute orally toxic. Based on the substance's corrosive properties further acute testing is not mandatory.
Reaction mass of Methyl dihydrogen phosphate and Orthophosphoric acid and Dimethyl hydrogen phosphatedoes not have to be classified as acute toxic.