(3E)-dec-3-en-2-one

Endpoint summary

Description of key information

The acute oral, dermal and inhalation toxicity of the target substance (3E)-dec-3-en-2-one was assessed in three in vivo studies conducted according to OECD test guideline 425, 402 and 403, respectively. Based on the results of the acute oral and dermal toxicity studies no classification is warranted for acute oral and dermal toxicity. Whereas, based on the results from the OECD 403 acute inhalation study, classifcation as Acute Tox. 4 (H332) is warranted in accordance with CLP Regulation 1272/2008.

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:

key study

Study period:

2009-04-16 to 2009-07-24

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 425 (Acute Oral Toxicity: Up-and-Down Procedure)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Deviations:

no

GLP compliance:

yes

Test type:

up-and-down procedure

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Remarks:

albino

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Received from Ace Animals, Inc., Boyertown, PA on April 7 and 21, 2009.
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: Young adult (9-10 weeks)
- Weight at study initiation: 170-186 g
- Housing: The animals were singly housed in suspended stainless steel caging with mesh floors, which conform to the size recommendations in the most recent Guide for the Care and Use of Laboratory Animals DHEW (NIH). Litter paper was placed beneath the cage and was changed at least three times per week.
- Diet (e.g. ad libitum): Purina Rodent Chow #5012
- Water (e.g. ad libitum): Filtered tap water was supplied ad libitum by an automatic water dispensing system.
- Fasting period: Prior to each dosing, experimentally naive rats were fasted overnight by removing the feed from their cages.
- Acclimation period: 7-15 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-23
- Humidity (%): 34-69
- Photoperiod (hrs dark / hrs light): 12 / 12

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

VEHICLE : none

DOSAGE PREPARATION:
Individual doses were calculated based on the initial body weights, taking into account the specific gravity (determined by EPSL) of the test substance.

Doses:

5000 mg/kg bw

No. of animals per sex per dose:

4

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were observed for mortality, signs of gross toxicity, and behavioral changes during the first several hours post-dosing and at least once daily thereafter for 14 days after dosing or until death occurred.
Observations included gross evaluation of skin and fur, eyes and mucous membranes, respiratory, circulatory, autonomic and central nervous systems, somatomotor activity and behavior pattern. Particular attention was directed to observation of tremors, convulsions, salivation, diarrhea, and coma. Individual body weights of the animals were recorded prior to test substance administration (initial) and again on Days 7 and 14 (termination) following dosing or after death.
- Necropsy of survivors performed: Surviving rats were euthanized via C02 inhalation at the end of the 14-day observation period. Gross necropsies were performed on all decedent and euthanized animals. Tissues and organs of the thoracic and abdominal cavities were examined.

Statistics:

N.a.

Preliminary study:

N.a.

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

One female died within two days of test substance administration. Prior to death, this animal was hypoactive and exhibited ano-genital staining, hunched posture, and soft feces.

Clinical signs:

other: One female died within two days of test substance administration. Prior to death this animal was hypoactive and exhibited ano-genital staining, hunched posture and soft faeces. The surviving animals exhibited ano-genital staining (3/3 animals) and/or were

Gross pathology:

Gross necropsy of the decedent revealed red intestines. No gross abnormalities were noted for the euthanized animals when necropsied at the conclusion of the 14-day observation period.

Interpretation of results:

GHS criteria not met

Conclusions:

In an acute oral toxicity study in rats conducted according to OECD 425, one female died within two days at a dose of 5000 mg/kg bw. Based on the results and in accordance with OECD guideline 425 the LD50 value was determined to be greater than 5000 mg/kg bw. Thus, the substance does not warrant classification as being toxic or harmful based upon its acute oral toxicity.

Executive summary:

An acute oral toxicity test was conducted in accordance with OECD test guideline 425 to determine the potential of (3E)-dec-3-en-2-one to induce acute oral toxicity in female Sprague-Dawley rats. An initial limit dose of 5000 mg/kg bw was administered to one healthy female rat by oral gavage. Due to the absence of mortality in this animal, two additional female animals received the same dose, one of which died. Therefore, a fourth animal was tested at this dose level and this animal survived. All animals were observed for mortality, signs of gross toxicity and behavioural changes at least once daily for 14 days.

Body weights were recorded prior to administration and again on Days 7 and 14 (termination) following dosing or after death. Necropsies were performed on all animals. One female died within two days of test substance administration. Prior to death this animal was hypoactive and exhibited ano-genital staining, hunched postures and soft faeces. The surviving females exhibited ano-genital staining, hunched posture, piloerection, reduced faecal volume, soft faeces and facial stains following test substance administration but recovered by Day 6 and appeared active and healthy, gaining bodyweight over the 14-day observation period. Gross necropsy of the decedent revealed red intestines; no gross abnormalities were noted for the euthanized animals when necropsied at the conclusion of the 14-day observation period. Based on the results the oral LD50 can be considered to greater than 5000 mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

GLP guideline study

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2009-04-16 to 2009-07-24

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1300 (Acute inhalation toxicity)

Deviations:

no

GLP compliance:

yes

Test type:

traditional method

Limit test:

no

Species:

rat

Strain:

not specified

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Received from Ace Animals, Inc., Boyertown, PA on March 31 and April 28, 2009.
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 9-11 weeks
- Weight at study initiation: 267 - 346 g (males) and 210 - 248 (females)
- Housing: The animals were singly housed in suspended stainless steel caging with mesh floors which conform to the size recommendations in the most recent Guide for the Care and Use of Laboratory Animals DHEW (NIH). Litter paper was placed beneath the cage and was changed at least three times per week.
- Diet (e.g. ad libitum): Purina Rodent Chow #5012
- Water (e.g. ad libitum): Tap water was supplied ad-libitum by an automatic water dispensing system except during exposure.
- Acclimation period: 13 - 20 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-23
- Humidity (%): 50-67
- Photoperiod (hrs dark / hrs light): 12 / 12

Route of administration:

inhalation

Type of inhalation exposure:

nose only

Vehicle:

air

Mass median aerodynamic diameter (MMAD):

>= 2.6 - <= 3 µm

Geometric standard deviation (GSD):

>= 1.85 - <= 1.87

Remark on MMAD/GSD:

An eight-stage Andersen cascade impactor was used to assess the particle size distribution of the test atmosphere. Samples were withdrawn
from the breathing zone of the animals at two intervals during each exposure. The filter paper collection stages were weighed before and after sampling to determine the mass collected upon each stage. The aerodynamic mass median diameter and geometric standard deviation were determined graphically using two-cycle logarithmic probit axes.

Details on inhalation exposure:

The exposure chamber, air supply and equipment used to measure particle size distribution, airflow and chamber concentration were the same as used during the pre-test trials and are described below.
- Nose-Only Exposure Chamber: A nose-only inhalation chamber with an internal volume of approximately 6.7 liters (Mini-Nose Only Inhalation Chamber, ADG Developments LTD) was used for exposure. Animals were individually housed in polycarbonate holding tubes which seal to the chamber with an "0" ring during exposure. The base unit terminates the chamber with a 0.5-inch diameter tube for discharged air.
- Air Supply: Filtered air was supplied by an air compressor (JUN-AIR, Model #6-15) to the spray atomization nozzle. Additional compressed mixing air, supplied from a compressed air tank (Airgas), was introduced into the chamber to help uniformly distribute the test atmosphere by creating a vortex at the chamber inlet. Compressed airflow was measured with a Mass Flowmeter (Omega, Model #FMA-5613). Chamber airflow was monitored throughout the exposure period and recorded periodically.
- Ambient Conditions: The temperature and relative humidity within the chamber as well as the room were monitored continuously during each exposure. In-chamber measurements were made with a Humidity-Temperature Indicator (Taylor, Model #5502) and room conditions were measured with a Temperature-Humidity Monitor (Dickson, Model #TH550). Temperature and humidity values were recorded every 15 minutes for the first hour of exposure and every 30 minutes thereafter.
- Atmosphere Generation: The test atmosphere was generated using a1/4 inch JCO atomizer (Spraying Systems Co.), FC3 fluid cap (Robert Miller Associates) and 70SS air cap (Spraying Systems Co.). The test substance was metered to the atomization nozzle through size 13 or 14 Viton tubing, using a peristaltic pump (Master Flex, Model #7520-35).
- Chamber Concentration Measurements: Gravimetric samples were withdrawn at 6 intervals from the breathing zone of the animals during each exposure. Samples were collected using 25 mm glass fiber filters (GF/B Whatman) in a filter holder attached by 1/4, inch tygon tubing to a vacuum pump (Reliance Electric, Model #G557X). Filter papers were weighed before and after collection to determine the mass collected. This value was divided by the total volume of air sampled to determine the chamber concentration. Sample airflows were measured using a Flowmeter (Omega, Model #FMA-5610).
- Exposure Period: For each exposure level, the animals were exposed to the targeted chamber concentration for at least 4 hours. At each level, the exposure period was extended beyond 4 hours to allow the chamber to reach equilibrium (T99). At the end of each exposure period, the generation was tenninated and the chamber was operated for a further 15 minutes with clean air. At the end of this period the animals were removed from the exposure tube. Prior to being returned to their cages, excess test substance was removed from the fur of each animal.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

>= 4 h

Remarks on duration:

At each level, the exposure period was extended beyond 4 hours to allow the chamber to reach equilibrium (T99). At the end of each exposure period, the generation was terminated and the chamber was operated for a further 15 minutes with clean air.

Concentrations:

0.52, 2.04 mg/L

No. of animals per sex per dose:

5 Males and 5 Females (2.04 mg/L)
5 Males (0.52 mg/L)

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: All animals were observed for mortality during each exposure period. All animals were observed for mortality during each exposure period. The animals were examined for signs of gross toxicity, and behavioral changes upon removal from the exposure chamber and at least once daily thereafter for up to 14 days or until death occurred. Observations included gross evaluation of skin and fur, eyes and mucous membranes, respiratory, circulatory, autonomic
and central nervous systems, somatomotor activity and behavior pattern. Particular attention was directed to observation of tremors, convulsions, salivation, diarrhea, and coma. Individual body weights of the animals were recorded prior to test substance exposure (initial) and again on Days 7 and 14 (termination) or after death.
- Necropsy of survivors performed: Surviving rats were euthanized via C02 inhalation on Day 14. Gross necropsies were performed on all decedents and euthanized animals. Tissues and organs of the thoracic and abdominal cavities were examined.

Key result

Sex:

male

Dose descriptor:

LC50

Effect level:

> 0.52 - < 2.04 mg/L air

Based on:

test mat.

Exp. duration:

4 h

Key result

Sex:

female

Dose descriptor:

LC50

Effect level:

> 2.04 mg/L air

Based on:

test mat.

Exp. duration:

4 h

Mortality:

At the 0.52 mg/L dose level one animal (male) died within one day of exposure to the test atmosphere. Prior to death, this animal was hypoactive and exhibited irregular respiration and moist rales.
At 2.04 mg/L one male died following exposure to the test atmosphere. There were no clinical signs observed for this animal prior to death. Two males died within two days of exposure to the test atmosphere. Prior to death these animals were hypoactive and exhibited abnormal respiration, nasal discharge, facial staining, hunched posture, reduced fecal volume and were cold to touch.

Clinical signs:

other: 0.52 mg/L exposure level: Clinical signs exhibited for the surviving animals included irregular respiration, rales, hunched posture, hypoactivity, reduced fecal volume, facial and/or ano-genital staining. However, these animals recovered by Day 7 gaining

Body weight:

At 0.52 mg/L survival animals gained weight.
At 2.04 mg/L three animals lost weight by Day 7, all animals gained body weight over the 14-day observation period.

Gross pathology:

At 0.52 mg/L gross necropsy of the decedent revealed extremely red lungs. No gross abnormalities were noted for any of the necropsied animals at the conclusion of the 14-day observation period.
At 2.04 mg/L gross necropsy of the decedent revealed edema and discoloration of the lungs, discoloration of the liver, gas distended yellow intestines and/or rigor mortis. No gross abnormalities were noted for the euthanized animals when necropsied at the conclusion of the 14-day observation period.

Table 1: Mortality data

Dose (mg/L)	Males	Females	Combined
0.52	1/5	-*	1/5
2.04	3/5	0/5	3/5

* Based on the results of the 2.04 mg!L exposure level, only five males were tested at the 0.5 mg/L level.

Table 2: Clinical observations

Observation	0.52 mg/L	2.04 mg/L
	Males*	Males*	Females
Rales	4/4	2/2	3/5
Irregular respiration	4/4	2/2	5/5
Hypoactivity	3/4	2/2	5/5
Reduced faecal volume	2/4	2/2	5/5
Ano-genital staining	2/4	0/2	0/5
Facial staining	2/4	2/2	4/5
Oral/nasal discharge (red)	0/4	0/2	3/5

* Data from surviving animals only are recorded, since intercurrent deaths occurred within 2 hours of the end of exposure.

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

Based on the results from an acute inhalation toxicity test conducted in accordance with OECD test guideline 403, it can be concluded that the acute inhalation LC50 is between 0.52 mg/L and 2.04 mg/L in male rats and is greater than 2.04 mg/L in female rats. According to CLP Regulation 1272/2008 classification as Acute Tox. 4, H332 is warranted.

Executive summary:

In an acute inhalation toxicity study (OECD 403, GLP) groups of young adult male and female rats were exposed by inhalation route to (3E)-dec-3-en-2-one for 4 hours nose only at concentrations of 0.52 and 2.04 mg/L. Animals were observed for 14 days. At the 0.52 mg/L exposure level five males were exposed. One animal died and clinical signs exhibited for the surviving animals included irregular respiration, rales, hunched posture, hypoactivity, reduced fecal volume, facial and/or ano-genital staining. However, these animals recovered by Day 7 gaining body weight and appearing active and healthy for the remainder of the 14-day observation period. Gross necropsy of the decedent revealed extremely red lungs. No gross abnormalities were noted for any of the necropsied animals at the conclusion of the 14-day observation period.

At the 2.04 mg/L exposure level five males and five females were exposed. One male died following exposure to the test atmosphere. Two males died within two days of exposure to the test atmosphere. Following exposure, clinical signs for the surviving animals included hypoactivity, hunched posture, abnormal respiration, reduced fecal volume, nasal and oral discharge and/or facial staining. However, these animals recovered by Day 10 and appeared active and healthy for the remainder of the study. Although three animals lost weight by Day 7, all animals gained body weight over the 14-day observation period. Gross necropsy of the decedent revealed edema and discoloration of the lungs, discoloration of the liver, gas distended yellow intestines and/or rigor mortis. No gross abnormalities were noted for the euthanized animals when necropsied at the conclusion of the 14-day observation period.

Under the conditions of this study, the acute·inhalation LC50 of the test substance is between 0.52 mg/L and 2.04 mg/L in male rats and is greater than 2.04 mg/L in female rats.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LC50

Value:

0.52 mg/m³ air

Quality of whole database:

GLP guideline study

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2009-04-16 to 2009-07-24

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Remarks:

albino

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Received from Ace Animals, Inc., Boyertown, PA on April 21, 2009.
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 8-9 weeks
- Weight at study initiation: 217 - 238 g (males) and 182 - 208 (females)
- Housing: The animals were singly housed in suspended stainless steel caging with mesh floors, which conform to the size recommendations in the most recent Guide for the Care and Use of Laboratory Animals DHEW (NIH). Litter paper was placed
beneath the cage and was changed at least three times per week.
- Diet (e.g. ad libitum): Purina Rodent Chow #5012
- Water (e.g. ad libitum): Filtered tap water ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-23
- Humidity (%): 51-66
- Photoperiod (hrs dark / hrs light): 12 / 12

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: 2 x 3 inches
- % coverage: 10% of the body surface
- Type of wrap if used: 3-inch Durapore tape

REMOVAL OF TEST SUBSTANCE
- Washing (if done): not specified, but the test sites were gently cleansed of any residual test substance
- Time after start of exposure: 24 hrs

TEST MATERIAL
- Amount(s) applied : 5000 mg/kg bw

VEHICLE
- Amount(s) applied : none

Duration of exposure:

24 hours

Doses:

5000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

Application of Test Substance:
Five thousand mg/kg of body weight of the test substance was applied evenly over a dose area of approximately 2 inches x 3 inches (approximately 10% of the body surface) and covered with a 2-inch x 3-inch, 4-ply gauze pad. The gauze pad and entire trunk of each animal were then wrapped with 3-inch Durapore tape to avoid dislocation of the pad and to minimize loss of the test substance. The rats were then returned to their designated cages. The day of application was considered Day 0 of the study.
After 24 hours of exposure to the test substance, the pads were removed and the test sites were gently cleansed of any residual test substance.

Body Weights:
Individual body weights of the animals were recorded prior to test substance application (initial) and again on Days 7 and 14 (termination) or after death.

Cage-Side Observations:
The animals were observed for mortality, signs of gross toxicity, and behavioral changes during the first several hours after application and at least once daily thereafter for up to 14 days or until death occurred. Observations included gross evaluation of skin and fur, eyes and mucous membranes, respiratory, circulatory, autonomic and central nervous systems, somatomotor activity and behavior pattern. Particular attention was directed to observation of tremors, convulsions, salivation, diarrhea, and coma.

Necropsy:
Surviving rats were euthanized via C02 inhalation at the end of the 14-day observation period. Gross necropsies were performed on decedent and euthanized animals. Tissues and organs of the thoracic and abdominal cavities were examined.

Statistics:

N.a.

Preliminary study:

N.a.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

One female died within two days of test substance application. Prior to death, this animal was hypoactive and exhibited prone posture.

Clinical signs:

other: The animal survivors were also hypoactive, but recovered by Day 2. Dermal irritation was noted at the dose site of all surviving animals between Days 1 and 14.

Gross pathology:

No abnormalities were observed at gross necropsy for the animals which survived until termination at day 14. Extremely red intestines were observed at gross necropsy for the animal which died during the study.

Other findings:

N.a.

Table 1: Mortality of tests animals

Dose (mg/kg bw)	Males	Females	Combined
5000	0/5	1/%	1/10

Table 2: Clinical observations

Observation	Males	Females
Mechanical damage due to unwrapping	5/5	5/5
Hypoactivity	4/5	4/5
Erythema	4/5	4/5
Light pink stain at dose site	5/5	5/5
Desquamation	5/5	3/5
Hyperkeratosis	0/5	1/5

Interpretation of results:

GHS criteria not met

Conclusions:

In an acute dermal toxicity study in rats conducted according to OECD 402, one female died within two days at a dose of 5000 mg/kg bw. Based on the results and in accordance with OECD guideline 402 the LD50 value was determined to be greater than 5000 mg/kg bw in male and female rats. Thus, the substance does not warrant classification as being toxic or harmful based upon its acute dermal toxicity.

Executive summary:

An acute dermal toxicity test was conducted in accordance with OECD test guideline 402 to determine the potential of (3E)-dec-3-en-2-one to induce acute dermal toxicity in male and female Sprague-Dawley rats. 5000 mg/kg bw was applied to the skin of 5 rats per sex for 24 hours. The animals were observed for mortality, signs of gross toxicity, and behavioural changes at least once daily for up to 14 days. Body weights were recorded prior to application and again on Days 7 and 14 (termination) or after death. Necropsies were performed on all animals.

One female died within two days of test substance application. Prior to death, this animal was hypoactive and exhibited prone posture. Seven survivors were also hypoactive but recovered by Day 2. Dermal irritation was noted at the dose site of all surviving animals between Days 1 and 14. Gross necropsy of the decedent revealed extremely red intestines. No gross abnormalities were noted for the euthanized animals when necropsied at the conclusion of the 14-day observation period. Under the conditions of this study, the single dose acute dermal LD50 of the test item is greater than 5000 mg/kg bw in male and female rats.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

GLP guideline study

Additional information

The acute oral, dermal and inhalation toxicity of the substance (3E)-decen-2 -one was assessed in three in vivo studies conducted according to OECD 425, 402 and 403, respectively.

An acute oral toxicity test was conducted in accordance with OECD test guideline 425 to determine the potential of (3E)-decen-2 -one to induce acute oral toxicity in female Sprague-Dawley rats. A limit dose of 5000 mg/kg bw was administered to female rats by oral gavage. All animals were observed for mortality, signs of gross toxicity and behavioural changes at least once daily for 14 days. One female died within two days of test substance administration. Prior to death this animal was hypoactive and exhibited ano-genital staining, hunched postures and soft faeces. The surviving females also exhibited ano-genital staining, hunched posture, piloerection, reduced faecal volume, soft faeces and facial stains following test substance administration but recovered by Day 6 and appeared active and healthy, gaining bodyweight over the 14-day observation period. Gross necropsy of the decedent revealed red intestines; no gross abnormalities were noted for the euthanized animals when necropsied at the conclusion of the 14-day observation period. Based on this results the oral LD50 can be considered to be greater than 5000 mg/kg bw.

In an acute inhalation toxicity study (OECD 403, GLP), groups of young adult male and female rats (five animals per sex) were exposed by inhalation (nose only) to 2.04 mg/L of (3E)-decen-2-one for 4 hours. In the same way, five additional male rats were also exposed (nose only) to 0.52 mg/L of (3E)-dec-3-en-2-one for 4 hours. Animals were observed for 14 days. At the 0.52 mg/L exposure level one male rat died. Surviving animals exhibited irregular respiration, rales, hunched posture, hypoactivity, reduced faecal volume, facial and/or ano-genital staining. However, these animals recovered by Day 7 gaining body weight and appearing active and healthy for the remainder of the 14-day observation period. Gross necropsy of the decedent revealed extremely red lungs. No gross abnormalities were noted for any of the necropsied animals at the conclusion of the 14-day observation period.

At the 2.04 mg/L no female rats died. While, one male died without exhibiting clinical signs following exposure to the target substance and two males died within two days of exposure to the target substance. Following the exposure, surviving male and female rats exhibited hypoactivity, hunched posture, abnormal respiration, reduced faecal volume, nasal and oral discharge and/or facial staining. However, these animals recovered by Day 10 and appeared active and healthy for the remainder of the study. Although three animals (one male and two females) lost weight by Day 7, all animals gained body weight over the 14-day observation period. Gross necropsy of the decedent revealed oedema and discoloration of the lungs, discoloration of the liver, gas distended yellow intestines and/or rigor mortis. No gross abnormalities were noted for the euthanized animals when necropsied at the conclusion of the 14-day observation period.Under the conditions of this study, the acute·inhalation LC50 of the test substance is considered to be between 0.52 mg/L and 2.04 mg/L in male rats and greater than 2.04 mg/L in female rats.

An acute dermal toxicity test was conducted in accordance with OECD test guideline 402 to determine the potential of (3E)-decen-2-one to induce acute dermal toxicity in male and female Sprague-Dawley rats. 5000 mg/kg bw was applied to the skin of five rats per sex for 24 hours.One female died within two days of test substance application. Prior to death, this animal was hypoactive and exhibited prone posture. Seven survivors were also hypoactive but recovered by Day 2. Dermal irritation was noted at the dose site of all surviving animals between Days 1 and 14. Gross necropsy of the decedent revealed extremely red intestines. No gross abnormalities were noted for the euthanized animals when necropsied at the conclusion of the 14-day observation period. Under the conditions of this study, the single dose acute dermal LD50 of the test substance is considered to be greater than 5000 mg/kg bw in male and female rats.

Justification for classification or non-classification

Based on the available data, (3E)-3 -decen-2 -one does not warrant classification for acute oral and dermal toxicity. The LD₅₀values for both the oral and the dermal route are above the limit dose of 2000 mg/kg bw of the CLP regulation (EC) No 1272/2008. While, based on the results of the acute inhalation study performed according to OECD test guideline 403, classification as Acute Tox. 4 (H332) is warranted in accordance with CLP Regulation 1272/2008.