Dibenzo[d,f][1,3,2]dioxaphosphepin, 6,6'-[[3,3',5,5'-tetrakis(1,1-dimethylethyl)[1,1'-biphenyl]-2,2'-diyl]bis(oxy)]bis-

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP OECD 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 403 (Acute Inhalation Toxicity)

Version / remarks:

adopted 07 Sep 2009

GLP compliance:

yes (incl. QA statement)

Remarks:

BASF SE, Experimental Toxicology and Ecology, 67056 Ludwigshafen, Germany

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Test material form:

not specified

Details on test material:

- Name of test material (as cited in study report): L4-Ligand
- Physical state: solid, white
- Analytical purity: 97.0 g/100 g
- Lot/batch No.: 0005473663
- Stability under test conditions: The stability under storage conditions over the study period was guaranteed by the sponsor.
- Storage condition of test material: Room temperature; under N2; protect against humidity

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories B.V., Kreuzelweg 53, 5961 NM Horst, The Netherlands
- Age at study initiation: male animals approx. 8 weeks, female animals approx. 10 weeks
- Weight at study initiation: mean: males: 232 g, females: 204 g
- Housing: Single housing or up to 5 animals per cage
- Diet: Kliba-Labordiät (Maus / Ratte Haltung “GLP”), Provimi Kliba SA, Kaiseraugst, Basel, Switzerland, ad libitum
- Water: Tap water ad libitum
- Acclimation period: for at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 30 - 70
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation: dust

Type of inhalation exposure:

nose/head only

Vehicle:

air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Head-nose inhalation system INA 10 (glass-steel construction, BASF SE, volume V ≈ 34 L): the animals were restrained in glass tubes and their snouts projected into the inhalation system.
- Exposure chamber volume: 34 L
- Source and rate of air: Compressed air is produced by an oil-free compressor (HT 6, Josef Mehrer GmbH & Co KG, Germany). For this purpose, air is filtered by an inlet air strainer and introduced into the compressor. After passed through an second ultra filter (SMF 5/3, 108 mm, Donalson), the compressed air (15 bar) is stored in a storage of 1500 or 5000 L. The compressed air is conducted to the labs via pipes, where the pressure is reduced to 6 bar. In the lab, the compressed air can be taken as required.
- Method of conditioning air: Central air conditioning system provides cold air of about 15°C. This cold air will pass through an activated charcoal filter, be adjusted to room temperature of 20 to 24°C and pass through a second particle filter (H13 (HEPA) Camfil Farr, Germany). The so generated conditioned air is used to generate inhalation atmospheres.
- System of generating particulates/aerosols: The dust was produced inside the dust pre-chamber with the Dosing-wheel dust generator and compressed air and passed via the cyclonic separator into the inhalation system.
- Method of particle size determination: Before sampling, the impactor were assembled with preweighed glass-fiber collecting discs, and equipped with a backup particle filter. The impactor was connected to the vacuum pump and two samples were taken from the breathing zone of the animals sampling occurred 30 minutes (or later) after the beginning of the exposure. The sample volume for each sample was 6 L. After sampling the impactor was taken apart. The collecting discs and the backup particle filter were re-weighed. The amounts of material adsorbed to the walls of the impactor and in the sampling probe (wall losses) were also determined quantitatively.
- Treatment of exhaust air: The flow was adjusted and continuously measured with a flowmeter.
- Temperature, humidity: 20.7 ± 0.4°C, 32.7 ± 3.6 % relative humidity

TEST ATMOSPHERE
- Brief description of analytical method used: Gravimetric measurement of the inhalation atmosphere concentration. Preweighed filters were placed into the filtration equipment. By means of the vacuum pump metered volumes of the dust were drawn through the filter. For each sample the dust concentration in mg/L was calculated from the difference between the preweight of the filter and the weight of the filter after sampling, with reference to the sample volume of the inhalation atmospheres. Mean and standard deviation were calculated for the concentration from the results of the individual measurements.
Calculation of the concentration:
For each sample the concentration was calculated in mg/L from the analytically determined mass values of the test substance in the samples and the respective volume sampled from the inhalation atmosphere. Mean and standard deviation were calculated for the concentration from the results of the individual measurements.
- Samples taken from breathing zone: yes

TEST ATMOSPHERE (if not tabulated)
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.):
Sample 1: MMAD: 2.7 µm and GSD: 2.0
Sample 2: MMAD: 2.9 µm and GSD: 2.0

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

1,868 mg /L (maximum technically attainable analytical concentration; the limit concentration of 5 mg/L could not be attained because the substance contains large fraction of coarse particles)

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: Individual body weights once during the acclimatization period, shortly before exposure (day 0) and at least on days 1, 3 and 7, and before the sacrifice of the animals at the end of the observation period. Detailed clinical observations were recorded for each animal separately several times during exposure and at least once daily on the pre-exposure day and during the observation period. A check for any dead or moribund animal was made twice each workday and once on Saturdays, Sundays and on public holidays.
- Necropsy of survivors performed: yes

Statistics:

In this study, only one concentration was tested, where no animals died. The result belonged to the type ”LC50 greater than”. Therefore, binomial test was used for statistical evaluation.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 1.868 mg/L air (analytical)

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: maximum technically attainable tested concentration

Mortality:

No lethality occurred at the maximum technically attainable tested concentration of 1,868 mg/L during the study period of 14 days.

Clinical signs:

other: Clinical signs and findings were observed during (up to 4 hours) and after exposure (> 4 hours) - see table 1. No abnormalities were detected in the animals during the post exposure observation period from study day 3 onwards.

Body weight:

The mean body weights of the animals decreased during the first post exposure observation day and increased from study day 3 onward.

Gross pathology:

No gross pathological abnormalities were noted during the necropsy in the animals at the termination of the study.

Any other information on results incl. tables

Table 1: Duration of clinical signs:

Test group 1 (1868 mg/L)	Male animals	Female animals
Fur, substance contaminated	d0	d0
Respiration, abdominal	d0 – d2	d0 – d2
Respiration, labored	h3 – h4	h3 – h4
Piloerection	d0 – d1	d0 – d2

Applicant's summary and conclusion

Interpretation of results:

practically nontoxic

Remarks:

Migrated information Criteria used for interpretation of results: EU