boron nitride (hexagonal)

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1990

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP conform study following US regulation for the enforcement of the "Federal Hazardous Substances Act 16 CFR 1500". Reports are not as detailed as modern protocols but include all required information. The principles and methodology used for testing are comparable to modern OECD 423 guideline. As no relevant deficiencies have been detected, the study is considered to be reliable.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: US Regulation of the Federal Hazardous Substances Act (16 CFR 1500)

Deviations:

no

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

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

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

boranylidyneamine

EC Number:

701-292-9

Cas Number:

10043-11-5

Molecular formula:

BN

IUPAC Name:

boranylidyneamine

Details on test material:

- Name of test material (as cited in study report): 89-006 (UHP 2020)
- Substance type: inorganic
- Physical state: solid
- Analytical purity: < 98.5 %
- Impurities (identity and concentrations): B2O3 0.1 %, carbon 0.4 %, ammonia 90 ppm, lead 20 ppm
- Stability under test conditions: stable
- Storage condition of test material: room temperature in plastic bag
- Particle size: D50 4.3 µm

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Sprague-Dawley Inc.
- Age at study initiation: young
- Weight at study initiation: 211-258 g
- Fasting period before study: yes
- Housing: wire mesh suspension cages, 5 per cage
- Diet (e.g. ad libitum): purina laboratory chow
- Water (e.g. ad libitum): water ad libitum
- Acclimation period: min. 2 days

ENVIRONMENTAL CONDITIONS
- Photoperiod (hrs dark / hrs light): 12 hrs light/12 hrs dark

Administration / exposure

Route of administration:

other: esophagel intubation

Vehicle:

corn oil

Remarks:

25% (v/v)

Doses:

5 g/kg body weight, calculated by using post-fasted body weights

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: Observation 2,5, 4,5 and 5 hours after dosing and once each day until end of the 14 day observation period. Body weights measured on the day of dosing and at the end of 14 day period.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

No deaths occured

Clinical signs:

other: other: No clinical signs observed

Gross pathology:

No observations in all rats

Other findings:

None

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The results of the performed test on acute oral toxicity of hexagonal boron nitride to rats demonstrated that the LD50 is > 5000 mg/kg body weight. Hexagonal boron nitride is therefore not classified as hazardous.

Executive summary:

Two groups, each of five male/female Sprague dawly rats, were treated with the test item by oral gavage administration at a dosage of 5000 mg/kg body weight. The test item was suspended in a vehicle (corn oil) at a concentration of 25% (v/v). All animals were allowed to acclimatise to the laboratory conditions for at least 2 days. The animals were observed for mortality/morbidity, clinical signs, body weights and examined macroscopically. All animals survived until the end of the 14-day observation period and no clinical signs were observed. At necropsy, no macroscopical findings were observed. Therefore, for hexagonal boron nitride the LD50 > 5000 mg/kg body weight and the substance should be not classified according to Annex I of Regulation (EC) 1272/2008.