[No public or meaningful name is available]

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 February 2021 - 4 March 2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Report date:

2021

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: Appendix to Director General Notification, No. 12-Nousan-8147. Agricultural Production Bureau, Ministry of Agriculture, Forestry and Fisheries of Japan (JMAFF)

Version / remarks:

November 2000, including most recent revisions

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EC No 440/2008, part B. Acute Toxicity (inhalation), May 2008, amended by COMMISSION REGULATION (EU) No 260/2014

Version / remarks:

January 2014

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1300 (Acute inhalation toxicity)

Version / remarks:

August 1998

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Version / remarks:

September 2009

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

traditional method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

N1,N3‐bis(3‐methylphenyl)‐5‐[(3‐methylphenyl)sulfamoyl]benzene‐1,3‐dicarboxamide

Molecular formula:

C29H27N3O4S

IUPAC Name:

N1,N3‐bis(3‐methylphenyl)‐5‐[(3‐methylphenyl)sulfamoyl]benzene‐1,3‐dicarboxamide

Test material form:

solid: particulate/powder

Details on test material:

- Appearance: Off-white powder
- Storage condition: At room temperature protected from light

Specific details on test material used for the study:

Physical description: Off-white powder
Storage conditions: At room temperature protected from light
Test item handling: No specific handling conditions required
Purity correction factor: No correction factor required

Test animals

Species:

rat

Strain:

other: Crl: WI(Han)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, Sulzfeld, Germany
- Females nulliparous and non-pregnant: yes
- Age at study initiation: approximately 9 weeks old
- Weight at study initiation: Males: 303 to 313 g; Females: 195 to 208 g.
- Housing: polycarbonate cages containing sterilized wooden fibers as bedding material; animals were group housed (up to 5 animals of the same sex ad the same exposure group together)
- For psychological/environmental enrichment, animals were provided paper (Enviro-dri), except when interrupted by study procedures/activities)
- Diet: ad libitum, pelleted rodent diet
- Water: ad libitum, municipal tap-water
- Acclimation period: at least 5 days
- Contaminants: Feed and water were analyzed; It is considered that there are no known contaminants in the feed and in the water that would interfere with the objectives of the study.

ENVIRONMENTAL CONDITIONS
- Temperature: 20 to 21°C (actual range)
- Humidity: 40 to 58%
- Air changes: 10 or greater air changes
- Photoperiod: 12-hour light/12-hour dark cycle

IN-LIFE DATES: From: 12 February 2021 To: 4 March 2021

Administration / exposure

Route of administration:

inhalation: dust

Type of inhalation exposure:

nose only

Vehicle:

air

Mass median aerodynamic diameter (MMAD):

>= 2.5 - <= 2.6 µm

Geometric standard deviation (GSD):

>= 2.1 - <= 2.3

Remark on MMAD/GSD:

The particle size distribution was characterized two times during the exposure period.

Target MMAD 1-4 µm, with range of 1.5-3 for gsd.

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: directed flow nose only inhalation chamber
- Exposure chamber volume: 20 L/min
- Method of holding animals in test chamber: Restraining tubes
- Source and rate of air (airflow): Administering the test item to a stream of pressurized air using a combination of a spiral feeder (Hethon 30) and an air mover (AIR-VAC, Milford, CT, USA) generated a dust. A magnetic vibrator was attached to the feeder to promote the feed. The dust was passed through a series of two cyclones, allowing larger particles to settle, before it entered the exposure chamber.
- Method of particle size determination: The particle size distribution was characterized twice during each exposure period. The samples were drawn with a flow of 2 L/min. from the test atmosphere through a tube mounted in one of the free animal ports of the exposure chamber. The samples were collected with an 8 stage Marple personal cascade impactor containing fiber glass filters (TE-290-GF. Tisch Environmental, Cleves, Ohio, USA) and a fiber glass back-up filter (SEC-290-F1, Westech, Upper Stondon, Bedfordshire, England). Amounts of test item collected were measured gravimetrically. Subsequently the Mass Median Aerodynamic Diameter (MMAD) and the Geometric Standard Deviation (GSD) were determined based on OECD guidance document No 39. Graphs of the cumulative mass of test item collected (percentage of total collected) against the cut points of the impactor stages were drawn on log-normal paper. When drawing the graphs more weight was given to the cut points where the cumulative mass sampled was within the range of 5 to 95%. The Mass Median Aerodynamic Diameter (MMAD), i.e. the particle size where 50% of the particle mass was borne by particles smaller than the MMAD and the σ84%, (the particle size where 84% of the particle mass was borne by particles smaller than the σ84%) was read from the graph. The geometric standard deviation (gsd) was calculated as σ84% / MMAD.
- Treatment of exhaust air: From the exposure chamber the test atmosphere was passed through a filter before it was released to the exhaust of the fume hood.
- Temperature and humidity in air chamber: The temperature of the atmosphere during the exposure was between 20.9 and 21.1 °C. The relative humidity was between 20 and 24%, which was considered appropriate for this relatively short 4 hours exposure duration.

TEST ATMOSPHERE
- Brief description of analytical method and equipment used: A total of 17 representative samples were taken for determination of the actual concentration during exposure. Samples were drawn from the test atmosphere through a tube mounted in one of the free animal ports of the exposure chamber. Samples were drawn through a glass fiber filter. Sample volumes were measured by means of a dry gas meter. The collected amount of test item in the air sample was measured gravimetrically. Subsequently the time-weighted mean concentration with the standard deviation was calculated.
- Samples taken from breathing zone: yes

TEST ATMOSPHERE
- MMAD was 2.6 μm (gsd 2.3) and 2.5 μm (gsd 2.1)

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

time-weighted mean actual concentration: 5.2 ± 0.2 mg/L.

No. of animals per sex per dose:

5 males and 5 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: Post exposure observations were performed at periodic intervals on the day of exposure (at least two times) and once daily thereafter.
- Frequency of weighing: Animals were weighed individually on Day 1 (pre exposure), 2, 4 and 8 and 15.
- Necropsy of survivors performed: yes
- Clinical signs: Animals were checked for mortality twice daily, behavioral signs of distress and effects on respiration at least three times during exposure.

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 5 mg/L air (analytical)

Exp. duration:

4 h

Mortality:

No mortality occurred.

Clinical signs:

other: During exposure, shallow/slow breathing was seen for all animals. After exposure, shallow/slow breathing, labored breathing, abnormal breathing sounds, hunched posture and/or erected fur was observed.

Body weight:

Overall body weight gain in males and females was within the range expected for rats of this strain and age used in this type of study and were therefore considered not indicative of toxicity.

Gross pathology:

No abnormalities were found at macroscopic post-mortem examination of the animals.

Other findings:

The time-weighted mean actual concentration was 5.2 ± 0.2 mg/L. The nominal concentration (amount of test item used divided by the volume of pressurized air used) was 129.8 mg/L.
This resulted in a generation efficiency (ratio of actual and nominal concentration) of 4.0%.
The particle size distribution was characterized two times during the exposure period. The MMAD was 2.6 μm (gsd 2.3) and 2.5 μm (gsd 2.1).

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

An acute inhalation toxicity study was performed according to OECD guideline 403 and in accordance with GLP principles. The inhalation LC50, 4h value of Pergafast 425 in Wistar Han rats was established to exceed 5 mg/L.

Executive summary:

An acute inhalation toxicity study was performed according to OECD guideline 403 and in accordance with GLP principles. Pergafast 425 was administered as a dust by nose only inhalation for 4 hours to one group of five male and five female Wistar Han rats at a target concentration of 5 mg/L. Mortality and clinical signs were observed daily during the observation period and body weights were
determined on Days 1, 2, 4, 8 and 15. Macroscopic examination was performed after terminal sacrifice (Day 15).
The time-weighted mean actual concentration was 5.2 ± 0.2 mg/L. The nominal concentration (amount of test item used divided by the volume of pressurized air used) was 129.8 mg/L.
This resulted in a generation efficiency (ratio of actual and nominal concentration) of 4.0%.
The results of the concentration measurements demonstrated that the item was sufficiently stable over time.
The particle size distribution was characterized two times during the exposure. The MMAD was 2.6 μm (gsd 2.3) and 2.5 μm (gsd 2.1).
No mortality occurred.
During exposure, shallow/slow breathing was seen for all animals. After exposure, shallow/slow breathing, labored breathing, abnormal breathing sounds, hunched posture and/or erected fur were was seen for all animals between Days 1 and 3. One male also showed hunched posture on Days 4 and 5.
Overall body weight gain in males and females was within the range expected for rats of this strain and age used in this type of study and were therefore considered not indicative of toxicity.
No abnormalities were found at macroscopic post-mortem examination of the animals.
The inhalation LC50, 4h value of Pergafast 425 in Wistar Han rats was established to exceed 5 mg/L.
Based on these results Pergafast 425 does not have to be classified and has no obligatory labelling requirement for acute inhalation toxicity according to the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) of the United Nations (2017) (including all amendments) and Regulation (EC) No 1272/2008 on classification, labelling and packaging of items and mixtures (including all amendments).