ethyl 2-acetyl-4-methyltridec-2-enoate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

17 November to 28 December 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

conducted under GLP conditions

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Reference 2

Reference Type:

other: report amendment number 01

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Version / remarks:

2009

Deviations:

yes

Remarks:

For the 5 mg/L exposure group, no clinical observations and body weights were recorded on Day 2. Evaluation: Sufficient data was available to warrant the study integrity. The study integrity was not adversely affected by the deviation.

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.2 (Acute Toxicity (Inhalation))

Deviations:

yes

Remarks:

For the 5 mg/L exposure group, no clinical observations and body weights were recorded on Day 2. Evaluation: Sufficient data was available to warrant the study integrity. The study integrity was not adversely affected by the deviation.

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1300 (Acute inhalation toxicity)

Version / remarks:

1998

Deviations:

yes

Remarks:

For the 5 mg/L exposure group, no clinical observations and body weights were recorded on Day 2. Evaluation: Sufficient data was available to warrant the study integrity. The study integrity was not adversely affected by the deviation.

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

ethyl 2-acetyl-4-methyltridec-2-enoate

EC Number:

816-455-0

Cas Number:

960253-23-0

Molecular formula:

C18H32O3

IUPAC Name:

ethyl 2-acetyl-4-methyltridec-2-enoate

Test material form:

liquid

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

- Species: Rat: Crl:WI(Han) (outbred, SPF-Quality) Recognized by international guidelines as the recommended test system (e.g. OECD, EC).
Source: Charles River Deutschland, Sulzfeld, Germany.

- Number of animals: 5 males and 5 females (females were nulliparous and non-pregnant) for the first exposure level and 5 males for the second exposure level.

- Age and body weight: Young adult animals were selected (approximately 9 weeks old). Animals used within the study were of approximately the same age and body weight variation did not exceed +/- 20% of the sex mean.

- Identification: Individual unique number by tattoo on hind leg.

- Health inspection: At least prior to exposure. It was ensured that the animals were healthy and without any abnormality that might affect the study integrity.

- Conditions:
Environmental controls for the animal room were set to maintain 18 to 24°C, a relative humidity of 40 to 70%, at least 10 air changes/hour, and a 12-hour light/12-hour dark cycle. Any variations to these conditions were maintained in the raw data and had no effect on the outcome of the study.

- Accommodation:
Group housing of five animals per sex per cage in labelled Makrolon cages (type IV; height 18 cm) containing sterilized sawdust as bedding material (Lignocel S 8-15, JRS - J.Rettenmaier & Söhne GmbH + CO. KG, Rosenberg, Germany) and paper as cage-enrichment (Enviro-dri, Wm. Lillico & Son (Wonham Mill Ltd), Surrey, United Kingdom). Acclimatization period was at least 5 days before start of treatment under laboratory conditions.

- Diet:
Free access to pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany) except during exposure to the test item.

- Water:
Free access to tap water except during exposure to the test item.

- Animal husbandry on the day of exposure:
The animals were moved to the inhalation area to in order to perform the exposure. During the exposure, there was no access to food and water. After exposure, the animals were returned to their cages which were placed in a fume cupboard for a short time period to allow test item remnants to evaporate. A sheet of filter paper was used to cover the bedding material to prevent suffocation in case of bad health condition and in order to recover and to aid the clinical observations. The sheet was removed and before the end of the exposure day, the surviving animals were returned to the animal room.

Diet, water, bedding and cage enrichment evaluation for contaminants and/or nutrients was performed according to facility standard procedures. There were no findings that could interfere with the study.

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose only

Vehicle:

air

Mass median aerodynamic diameter (MMAD):

>= 2.9 - <= 3.1 µm

Geometric standard deviation (GSD):

>= 1.9 - <= 2.4

Remark on MMAD/GSD:

The Mass Median Aerodynamic Diameter (MMAD) and geometric standard deviation (gsd) were determined twice during the exposure period.

Details on inhalation exposure:

aerosol and nose only for 4 hours

Target concentrations were based on the cut off concentration values specified in the UN and EC classification guidelines. Five animals of each sex were exposed in a limit test for 4 hours to a target concentration of the test item of 5 mg/L. Based on the results, the males were identified as most sensitive sex and therefore one additional group of five males was exposed to the next lower target concentration of 1 mg/L.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

5mg/l and 1mg/l

No. of animals per sex per dose:

5 males and 5 females (females were nulliparous and nonpregnant) for the first exposure level and 5 males for the second exposure level.

Control animals:

no

Details on study design:

Assessment of acute inhalation toxicity with GR-86-6599 in the rat (nose-only)
The study was carried out based on the guidelines described in:
• OECD Guidelines, Section 4, Health Effects. No.403, "Acute Inhalation Toxicity", Sep 2009.
• Commission Regulation (EC) No 440/2008, B.2. Acute Toxicity (inhalation), L142, May 2008.
• EPA OPPTS 870.1300, Acute inhalation Toxicity. EPA 712-C-98-193, August 1998.
• JMAFF Guidelines (2000), including the most recent revisions.
GR-86-6599 was administered as an aerosol by nose-only inhalation for 4 hours to two groups of five male and five female Wistar rats. Mortality and clinical signs were observed daily during the observation period and body weights were determined on Days 1, 2, 4, 8 and 15 and at death. Macroscopic examination was performed on the day of death or after terminal sacrifice (Day 15).
For the 5 mg/L exposure group, the time-weighted mean actual concentration was 5.1 ± 0.1 mg/L. The nominal concentration (amount of test item used divided by the volume of pressurized air used) was 6.9 mg/L. The generation efficiency (ratio of actual and nominal concentration) was 74%. For the 1 mg/L exposure group, the time-weighted mean actual concentration was 1.2 ± 0.03 mg/L. The nominal concentration (amount of test item used divided by the volume of pressurized air used) was 1.7 mg/L. The generation efficiency (ratio of actual and nominal concentration) was 67%. The concentration measurements equally distributed over time showed that the item was sufficiently stable.
The Mass Median Aerodynamic Diameter (MMAD) and geometric standard deviation (gsd) were determined twice during the exposure period. At 5 mg/L, the MMAD was 3.0 μm (gsd 1.9) and 3.0 μm (gsd 2.1). At 1 mg/L, the MMAD was 2.9 μm (gsd 2.0) and 3.1 μm (gsd 2.4)

Statistics:

No statistical analysis was performed.

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 1 - < 5 mg/L air (analytical)

Based on:

test mat.

Exp. duration:

4 h

Mortality:

At 5 mg/L, one male was found dead and one male and one female were sacrificed for humane reasons on Day 3. Two males were sacrificed between Days 7 and 9. No further mortality occurred in any of the other animals assigned to the study

Clinical signs:

other: After exposure at 5 mg/L, lethargy, hunched posture, slow breathing, labored respiration, rales, piloerection and ptosis up to Day 9. Scaleson the back of the females - Days 10 and 13. After exposure at 1 mg/L, hunched posture and rales - Days 1 and 4.

Body weight:

At 5 mg/L, body weight loss was noted for all surviving animals during the first week post exposure. All animals regained weight during the second week.
At 1 mg/L, the body weight gain shown by the animals over the study period was within the range expected for rats of this strain and age used in this type of study and was therefore considered not indicative of toxicity.

Gross pathology:

At 5 mg/L, macroscopic post mortem examination of the animals that were found dead or sacrificed for ethical reasons during the study revealed abnormalities of the lungs (pale with many dark red or black), stomach and intestines (distended with gas) and thymus (many dark red foci). No abnormalities were seen for the surviving animals

At 1 mg/L, no abnormalities were found at macroscopic examination of the animals.

Incidental findings included advanced autolysis for one male found dead (5 mg/L). This finding was toxicologically not relevant.

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

The inhalation LC50, 4h value of GR-86-6599 in Wistar rats was established to be within the range of 1 – 5 mg/L.

Executive summary:

Assessment of acute inhalation toxicity with GR-86-6599 in the rat (nose-only)

The study was carried out based on the guidelines described in:

• OECD Guidelines, Section 4, Health Effects. No.403, "Acute Inhalation Toxicity", Sep 2009.

• Commission Regulation (EC) No 440/2008, B.2. Acute Toxicity (inhalation), L142, May 2008.

• EPA OPPTS 870.1300, Acute inhalation Toxicity. EPA 712-C-98-193, August 1998.

• JMAFF Guidelines (2000), including the most recent revisions.

GR-86-6599 was administered as an aerosol by nose-only inhalation for 4 hours to two groups of five male and five female Wistar rats. Mortality and clinical signs were observed daily during the observation period and body weights were determined on Days 1, 2, 4, 8 and 15 and at death. Macroscopic examination was performed on the day of death or after terminal sacrifice (Day 15).

For the 5 mg/L exposure group, the time-weighted mean actual concentration was 5.1 ± 0.1 mg/L. The nominal concentration (amount of test item used divided by the volume of pressurized air used) was 6.9 mg/L. The generation efficiency (ratio of actual and nominal concentration) was 74%. For the 1 mg/L exposure group, the time-weighted mean actual concentration was 1.2 ± 0.03 mg/L. The nominal concentration (amount of test item used divided by the volume of pressurized air used) was 1.7 mg/L. The generation efficiency (ratio of actual and nominal concentration) was 67%. The concentration measurements equally distributed over time showed that the item was sufficiently stable.

The Mass Median Aerodynamic Diameter (MMAD) and geometric standard deviation (gsd) were determined twice during the exposure period. At 5 mg/L, the MMAD was 3.0 μm (gsd 1.9) and 3.0 μm (gsd 2.1). At 1 mg/L, the MMAD was 2.9 μm (gsd 2.0) and 3.1 μm (gsd 2.4)

At 5 mg/L, one male was found dead and one male and one female were sacrificed for humane reasons on Day 3. Two males were sacrificed between Days 7 and 9. No further mortality occurred in any of the other animals assigned to the study.

At 5 mg/L, slow respiration was noted during exposure. After exposure, lethargy, hunched posture, slow breathing, labored respiration, rales, piloerection and ptosis were seen for the animals up to Day 9. Scales were seen on the back of the females between Days 10 and 13. At 1 mg/L, no abnormalities were noted during exposure. After exposure, hunched posture and rales were seen for the animals between Days 1 and 4.

At 5 mg/L, body weight loss was noted for all surviving animals during the first week post exposure. All animals regained weight during the second week. At 1 mg/L, the body weight gain shown by the animals over the study period was considered not indicative of toxicity.

At 5 mg/L, macroscopic post mortem examination of the animals that were found dead or sacrificed for ethical reasons during the study revealed abnormalities of the lungs (pale with many dark red or black), stomach and intestines (distended with gas) and thymus (many dark red foci). No abnormalities were seen for the surviving animals. At 1 mg/L, no abnormalities were found at macroscopic examination of the animals.

The inhalation LC50, 4h value of GR-86-6599 in Wistar rats was established to be within the range of 1 – 5 mg/L.