Ethyl butyrate

Endpoint summary

Description of key information

Acute oral toxicity: 

Acute oral toxicity dose (LD50) of test chemical was considered based on experimental study conducted on rats, the LD50 value was considered to be >2000 mg/kg bw in rats. Thus, comparing this value with the criteria of CLP regulation, the test chemical cannot be classified for acute oral toxicity.

Acute Inhalation toxicity:

The acute Inhalation toxicity dose (LC50) for test chemical was considered based on the data available for the structurally and functionally similar read across chemicals. The study concluded that the LC50 value is >5 mg/L(>5000 mg/m3), for acute inhalation toxicity. Thus, comparing this value with the criteria of CLP regulation, test chemical cannot be classified for acute inhalation toxicity.

Acute Dermal Toxicity:

Acute Dermal toxicity dose (LD50) for test chemical was considered based on different experimental studies conducted on rats and rabbits, the value was considered to be >2000 mg/kg bw in rats and rabbits. Thus, comparing this value with the criteria of CLP regulation, the test chemical cannot be classified for acute dermal toxicity.

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

data is from experimental reports following standard procedures.

Qualifier:

according to guideline

Guideline:

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

Principles of method if other than guideline:

To determine the acute oral toxicity of test chemical in Sprague Dawley rats

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Specific details on test material used for the study:

- Substance Type: Organic
- Physical State: Liquid

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 0001
- Expiration date of the lot/batch:July; 2021
- Manufacturing Date: July; 2016

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Test Item and prepared formulation(s) were stored at ambient temperature.

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: The dose of 300 mg/kg of test item was prepared by dilution of the test item in distilled water to obtain 30 mg/ml strength of solution. The formulation was prepared fresh on the day of dosing. The test item was administered in the dose volume of 10 ml/kg body weight. Actual preparation procedures are documented in the raw data. The dose of 2000 mg/kg of test item was administered undiluted as supplied by the Sponsor.

OTHER - Safety Precautions: Safety precautions included use of protective clothing, gloves, masks and eye protection (glasses).

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: National Institute of Biosciences, Pune.
- Females (if applicable) nulliparous and non-pregnant: [yes/no] : yes
- Age at study initiation: Healthy young adult females were used. The age at study initiation was 8 to 12 weeks old
- Weight at study initiation: Body weights at the start : Female Mean : 199.48 g (= 100 %); Minimum : 194.3 g (- 2.60 %); Maximum : 207.2 g (+ 3.87 %)
- Fasting period before study: fasted rats (approximately 16 hours or more)
- Housing:polycarbonate cages.
- Diet (e.g. ad libitum): Rodent feed supplied by the Nutrivet Life Sciences, Pune, was provided ad libitum from individual feeders.
- Water (e.g. ad libitum):Water was provided ad libitum from individual bottles attached to the cages. All water was from a local source and passed through the reverse osmosis membrane before use.
- Acclimation period:All animals were acclimatized to laboratory conditions for minimum of 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20.4 to 22.0 degree centigrade
- Humidity (%): 53.1% to 58.2%.
- Air changes (per hr): ten to fifteen air changes per hour of 100% fresh air that had been passed through the HEPA filters
- Photoperiod (hrs dark / hrs light): An artificial light and dark cycle of 12 hours each was provided to the room.

IN-LIFE DATES: From: 31-05-2017 To: 19-06-2017

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 300 mg/kg and 2000 mg/kg
- Amount of vehicle (if gavage):10 ml per kg of body weight

MAXIMUM DOSE VOLUME APPLIED: 10 ml per kg of body weight was considered the maximum volume which could be administered to a rat.

DOSAGE PREPARATION (if unusual): The dose of 300 mg/kg of test item was prepared by dilution of the test item in distilled water to obtain 30 mg/ml strength of solution.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose:The doses were selected based on the available literature of the test item.

Doses:

Dose Group I : 300 mg/kg
Dose Group II : 2000 mg/kg

No. of animals per sex per dose:

Three females were used at each step

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Clinical Observations and General Appearance: Animals were observed for clinical signs, mortality and morbidity, until sacrifice.Onset, duration and severity of any sign were recorded. The clinical signs and mortality observations were conducted at immediately (0 to 5 minutes), 5, 10, 30, 60 minutes, 2, 4 and 6 hours on the day of dosing and once daily thereafter for 14 day. Daily observation was done as far as possible at the same time. The observations were included general clinical signs, observations of eyes, mucous membranes, respiratory, circulatory system and behavior pattern.
Body weights: Individual animal body weights were recorded, before fasting, prior to administration of the test item (fasting body weights), weekly thereafter and at termination on day 14. Weight changes were calculated and recorded.
Gross Pathology: Necropsy was performed on all animals at the end of the study period on day 15. Macroscopic examination of all the orifices, cavities and tissues were made and the findings were recorded. All animals surviving the study period were sacrificed by the carbon dioxide asphyxiation technique.
Histopathology: No gross abnormalities were observed in animals sacrificed terminally hence, no histopathology was performed.

Statistics:

Mean ± SD

Preliminary study:

not specified

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: No mortality was observed

Mortality:

No mortality was observed at all the tested concentrations at all times

Clinical signs:

other: No clinical signs and signs of toxicity were observed.

Gross pathology:

Gross pathological examination did not reveal any abnormalities in animals from 300 mg/kg and 2000 mg/kg dose groups.

Other findings:

- Histopathology: No gross abnormalities were observed in animals sacrificed terminally hence, no histopathology was performed.

Table 1: Summary of Clinical Signs of Toxicity and Mortality

Sprague Dawley Rat

Sex : Female

Group I :   

Step No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days From - to	Mortality
I	300	No clinical signs observed	3	1,2,3	Day 0 - Day 14	0/3

 

 

 

Group I :

Step No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days From - to	Mortality
II	300	No clinical signs observed	3	4,5,6	Day 0 - Day 14	0/3

 

Group II :

Step No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days From - to	Mortality
I	2000	No clinical signs observed	3	7,8,9	Day 0 - Day 14	0/3

 

Group II :

Step No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days From - to	Mortality
II	2000	No clinical signs observed	3	10,11, 12	Day 0 - Day 14	0/3

 

 

 

Table 2: Mean Body Weight and Percent Body Weight Gain (g)

Sprague Dawley Rat

Sex : Female

Group I :

Step No.	Dose (mg/kg body weight)		Before Fasting Body weight	Body weight Day 7	% body weight gain day 0-7	Body weight Day 14	% body weight gain day 7- 14	% body weight gain day 0- 14
I	300	Mean	199.03	205.60	3.32	223.10	8.51	12.11
		± SD	3.23	1.90	2.28	2.48	0.63	2.11

 

 

Group I :

Step No.	Dose (mg/kg body weight)		Before Fasting Body weight	Body weight Day 7	% body weight gain day 0-7	Body weight Day 14	% body weight gain day 7- 14	% body weight gain day 0- 14
II	300	Mean	203.43	209.37	2.91	227.20	8.52	11.68
		± SD	4.60	5.75	0.75	5.64	0.37	0.43

 

 

Group II :

Step No.	Dose (mg/kg body weight)		Before Fasting Body weight	Body weight Day 7	% body weight gain day 0-7	Body weight Day 14	% body weight gain day 7- 14	% body weight gain day 0- 14
I	2000	Mean	199.17	206.67	3.77	227.90	10.27	14.43
		± SD	2.14	2.81	1.00	4.19	0.67	1.78

 

 

Group II :

Step No.	Dose (mg/kg body weight)		Before Fasting Body weight	Body weight Day 7	% body weight gain day 0-7	Body weight Day 14	% body weight gain day 7- 14	% body weight gain day 0- 14
II	2000	Mean	196.30	201.80	2.80	220.83	9.44	12.50
		± SD	2.17	2.61	0.20	1.40	1.13	0.94

 

Table 3: Summary of Gross Pathological Findings

Sprague Dawley Rat

Sex : Female

 

        Group I :

Step No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	300	1 - 3	TS	No abnormality detected

 

 

        Group I :

Step No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
II	300	4 - 6	TS	No abnormality detected

 

 

                    Group II :

 

Step No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	2000	7 - 9	TS	No abnormality detected

 

 

                    Group II :

 

Step No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
II	2000	10 - 12	TS	No abnormality detected

 

                     TS = Terminal Sacrifice

 

                    

 

 

 

Interpretation of results:

other: Not classified

Conclusions:

The acute oral LD50 value for test chemical can be considered to be >2000mg/kg. Hence, it was concluded that the acute toxicity of test chemical, when administered via oral route in Sprague Dawley rats falls into the “Category Not classified” criteria of CLP.

Executive summary:

The study was designed and conducted to determine the acute oral toxicity profile of test chemical in Sprague Dawley rats. The study was performed according to OECD 423 - Acute Toxic Class Method. Initially, three female animals were treated at the dose level of 300 mg/kg body weight of the test item (Group I Step I). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality at 24 hours after the dosing. As no mortality was observed at 24 hours after the dosing, three female animals were added to the study and treated with the same dose of 300 mg/kg of the test item (Group I Step II). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality after the dosing. As no mortality was observed at 300 mg/kg dose group, hence additional three female animals were treated with the higher dose of 2000 mg/kg of the test item (Group II Step I). Administration of the test item at 2000 mg/kg did not result in any signs of toxicity and mortality after the dosing. As no mortality were observed at 24 hours after the dosing, additional three female animals were treated with the higher dose of  2000 mg/kg of the test item (Group II Step II). Administration of the test item at 2000 mg/kg did not result in any signs of toxicity and mortality after the dosing. No mortality or gross pathological abnormalities were observed in animals from 300 mg/kg and 2000 mg/kg dose groups. Therefore, the acute oral LD50 value for test chemical can be considered to be >2000mg/kg. Hence, it was concluded that the acute toxicity of test chemical, when administered via oral route in Sprague Dawley rats falls into the “Category Not classified” criteria of CLP.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

Data is Klimisch 1 and from experimental study report.

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

Experimental data of read across substances

Justification for type of information:

Data for the target chemical is summarized based on the structurally and functionally similar read across chemicals

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: As mentioned below

Principles of method if other than guideline:

WoE report is based on two acute inhalation toxicity studies as- WoE 2 and WoE 3.
Acute inhalation toxicity test was carried out to study the effects of the test chemicals on rodents

GLP compliance:

not specified

Test type:

other: not specified

Limit test:

no

Species:

rat

Strain:

other: 1. Sprague-Dawley 2. not specified

Sex:

male/female

Details on test animals or test system and environmental conditions:

1. TEST ANIMALS
- Source: Charles River UK
- Age at study initiation: 6 to 8 weeks
- Weight at study initiation: ca. 200 g
- Housing: Animals were kept in cages.
- Diet (e.g. ad libitum): Food was provided
- Water (e.g. ad libitum): water was provieded
2. not specified

Route of administration:

other: 1. inhalation: aerosol 2. inhalation

Type of inhalation exposure:

other: 1. whole body 2. not specified

Vehicle:

other: 1. clean air 2. not specified

Mass median aerodynamic diameter (MMAD):

5.8 µm

Geometric standard deviation (GSD):

2.23

Remark on MMAD/GSD:

1. Sampling with a Marple cascade impactor 35 minutes after the start of exposure.
2. not specified

Details on inhalation exposure:

1. GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: exposure chamber
- Exposure chamber volume: 120 L
- Method of holding animals in test chamber: Animals were held in 10 separate animal compartments.
- Source and rate of air: Respirable aerosol in clean dried air produced by aerosol generator (equilibration period 9 min),
- Temperature, humidity, pressure in air chamber: supply pressure 15 l/min, flow rate in the exposure chamber: 0.8 ml/min per pump, total flow rate 1.6 ml/min.

TEST ATMOSPHERE (if not tabulated)
- Particle size distribution:
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.): mass median aerodynamic diameter (MMAD): 5.8 µm, geometric standard deviation: 2.23, 59.5% in the respirable range (< 7 µm).

CLASS METHOD (if applicable)
- Rationale for the selection of the starting concentration: Analytical determination, sampling through a gas absorption trap, 3 samples were taken during the exposure period
2. not specified

Analytical verification of test atmosphere concentrations:

not specified

Duration of exposure:

1 h

Remarks on duration:

not specified

Concentrations:

1. 7.38 mg/l +- 0.131 (nominal 58 mg/l or 7380 mg/m3)
2. 4000 ppm

No. of animals per sex per dose:

1. 5 males, 5 females per group
2. not specified

Control animals:

other: 1. yes, clean air only 2. not specified

Details on study design:

1. - Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Clinical signs: continuously during exposure, twice daily during the observation period.
Body weights: daily. Food and water consumption per cage.
- Necropsy of survivors performed: yes
- Other examinations performed: Macroscopic organ examination at necropsy, lung weights.
2. not specified

Statistics:

1. not specified
2. not specified

Preliminary study:

1. not specified
2. not specified

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 7 380 mg/m³ air (analytical)

Based on:

test mat.

Exp. duration:

1 h

Remarks on result:

other: No mortality was observed

Sex:

not specified

Dose descriptor:

LC50

Effect level:

> 4 000 ppm

Based on:

test mat.

Remarks on result:

other: No mortality was observed

Mortality:

1. No mortality was observed at 7380 mg/m3.
2. No mortality was observed

Clinical signs:

other: 1. During observation period, immediately after removal from the exposure chamber: exaggerated respiratory movements and matted fur (all rats), wet fur around the snout and jaws (2 males) and clear discharge from the eyes (3 females), brown staining aroun

Body weight:

1. Slightly reduced body weight and food consumption on day 1, thereafter comparable to control. Water consumption not affected.
2. not specified

Gross pathology:

1. At necropsy there were no macroscopic abnormalities in the rats.
2. not specified

Other findings:

1. Lung to body weight ratio were comparable between test and control animals.
2. not specified

Interpretation of results:

other: Not classified

Conclusions:

According to CLP regulation, the test chemical test chemical cannot be classified for acute inhalation toxicity, as the LC50 value is >5 mg/L (>5000 mg/m3).

Executive summary:

Data available for the structurally and functionally similar read across chemicals has been reviewed to determine the acute inhalation toxicity of the test chemical.The studies are as mentioned below:

1. Acute inhalation toxicity study of test chemical was conducted in 10 male and female Sprague-Dawley rats at the dose concentration of 7380 mg/m3 (7.38 mg/l). The exposure was given to whole body, respirable aerosol in clean dried air produced by aerosol generator (equilibration period 9 min), and exposure chamber 120 l with 10 separate animal compartments. The control animals received clean air only. Animals were observed for - clinical signs: continuously during exposure, twice daily during the observation period; body weights: daily; Food and water consumption per cage. Necropsy of survivors was performed. Macroscopic organ examination at necropsy and lung weights was done. No mortality was observed at 7380 mg/m3.During observation period, immediately after removal from the exposure chamber: exaggerated respiratory movements and matted fur (all rats), wet fur around the snout and jaws (2 males) and clear discharge from the eyes (3 females), brown staining around the snout and jaws (1 female) were observed. All symptoms were reversible within 24 hours. Slightly reduced body weight and food consumption on day 1, thereafter comparable to control. Water consumption not affected. At necropsy there were no macroscopic abnormalities in the rats. Lung to body weight ratio were comparable between test and control animals. Therefore, LC50 value was considered to be >7380 mg/m3, when 10 male and female Sprague-Dawley rats were treated with test chemical via inhalation route by aerosol to whole body exposure for 1 hour.

2. The acute inhalation toxicity study was conducted by using test chemical in rats at the concentration of 4000 ppm. No mortality was observed at 4000 ppm. Hence, LC50 value was considered to be >4000 ppm, when rats were exposed to test chemical via inhalation route.

Thus, based on the above summarised studies, test chemical and it’s structurally and functionally similar read across substances, it can be concluded that LC50 value is >5 mg/L. Thus, comparing this value with the criteria of CLP regulation, test chemical cannot be classified for acute inhalation toxicity.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC50

Value:

5 000 mg/m³ air

Quality of whole database:

Data is Klimisch 2 and from authoritative database.

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

data is from experimental reports following standard procedures

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Principles of method if other than guideline:

To determine the acute dermal toxicity of test chemical in Sprague Dawley rats.

GLP compliance:

yes

Test type:

fixed dose procedure

Limit test:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 0001
- Expiration date of the lot/batch:July; 2021
- Manufacturing Date: July; 2016

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Test Item and prepared formulation(s) were stored at ambient temperature.

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: The test item was used undiluted and as supplied by the Sponsor.

OTHER - Safety Precautions: Safety precautions included use of protective clothing, gloves, masks and eye protection (glasses).

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Sex: Male and Female
- Source: National Institute of Biosciences, Pune.
- Age at study initiation: Young adult male and female rats aged between 8 – 12 weeks
- Weight at study initiation: Body weights at the start : Male - Mean: 258.62 g (= 100 %); Minimum : 251.4 g (- 2.79 %); Maximum : 266.4 g (+ 3.01 %)
Total No. of animals : 5
Female- Mean : 230.04 g (= 100 %); Minimum : 224.3 g (- 2.50 %); Maximum : 238.4 g (+ 3.63 %)
Total No. of animals : 5
- Housing:individually housed in polycarbonate cages with paddy husk as bedding
- Diet (e.g. ad libitum): Rodent feed supplied by the Nutrivet Life Sciences, Pune, was provided ad libitum from individual feeders.
- Water (e.g. ad libitum):Water was provided ad libitum from individual bottles attached to the cages. All water was from a local source and passed through the reverse osmosis membrane before use.
- Acclimation period:All animals were acclimatized to laboratory conditions for minimum of 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20.4 to 22.0 degree centigrade
- Humidity (%): 55.4% to 58.8%.
- Air changes (per hr): ten to fifteen air changes per hour of 100% fresh air that had been passed through the HEPA filters
- Photoperiod (hrs dark / hrs light): An artificial light and dark cycle of 12 hours each was provided to the room.

IN-LIFE DATES: From: 06-06-2017 To: 21-06-2017

Type of coverage:

occlusive

Vehicle:

water

Details on dermal exposure:

TEST SITE
- Area of exposure: dorsal surface and sides from scapular to pelvic area
- % coverage: approximately 10% of the total body surface area
- Type of wrap if used: using a porous gauze dressing and non irritating tape
REMOVAL OF TEST SUBSTANCE

- Washing (if done): yes, the wrapping was removed and the test site wiped free of excess test item. Distilled water was used to remove residual test item.
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg

Duration of exposure:

24 hrs

Doses:

2000 mgkg

No. of animals per sex per dose:

A single dose of 2000 mg of the test item per kilogram of body weight was administered to ten rats (five males and five females).

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Clinical Observations and General Appearance: Animals were observed for clinical signs, mortality, until sacrifice. Onset, duration and severity of any sign were recorded. The clinical signs and mortality observations were conducted at 10, 30, 60 minutes, 2, 4 and 6 hours on the day of dosing and once daily thereafter for 14 day. Daily observation was done as far as possible at the same time. The observations were included general clinical signs, observations of eyes, mucous membranes, respiratory, circulatory system and behavior pattern.
Evaluation of Dermal Reaction: Dermal reaction was observed daily for study period of 14 days.
Body weights: Individual animal body weights were recorded pre-test (prior to administration of the test item), day 7 and at termination on day 14.
Gross Pathology: Necropsy was performed on animals surviving at the end of the study. Macroscopic examination of all the orifices, cavities and tissues were made and the findings were recorded. All animals surviving the study period were sacrificed by the carbon dioxide asphyxiation technique (day 15).
Histopathology: No gross abnormalities were observed in animals sacrificed terminally hence, no histopathology was performed.

Statistics:

not specified

Preliminary study:

not specified

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: no other details available

Mortality:

Sex : Male Group I - Animal treated at the dose level of 2000 mg/kg body weight did not result in any signs of toxicity during the study period of 14 days. All animals survived through the study period of 14 days.
Sex : Female Group I - Animal treated at the dose level of 2000 mg/kg body weight did not result in any signs of toxicity during the study period of 14 days. All animals survived through the study period of 14 days

Clinical signs:

other: Sex : Male Group I - Animal treated at the dose level of 2000 mg/kg body weight did not result in any skin reaction during the study period of 14 days. Sex : Female Group I - Animal treated at the dose level of 2000 mg/kg body weight did not result in an

Gross pathology:

Gross pathological examination did not reveal any abnormalities in animals from 2000 mg/kg dose group

Other findings:

Evaluation of Dermal Reaction - Animal treated at the dose level of 2000 mg/kg body weight did not result in any skin reaction during the study period of 14 days.

Table 1: Summary of Clinical Signs of Toxicity and Mortality

Sprague Dawley Rat

Sex : Male

Group  No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	2000	No clinical signs observed	5	1 - 5	Day 0 - Day 14	0/5

 Sex : Female

 

Group  No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	2000	No clinical signs observed	5	6 - 10	Day 0 - Day 14	0/5

Table 2: Summary of Evaluation of Dermal Reaction

Sprague Dawley Rat

Sex : Male 

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	2000	No dermal reaction observed	5	1 - 5	Day 0 - Day 14	0/5

 

Sex : Female

 

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	2000	No dermal reaction observed	5	6 - 10	Day 0 - Day 14	0/5

 

Table 3: Mean Body Weight and Percent Body Weight Gain (g)

Sprague Dawley Rat

Sex : Male

Group No.	Dose (mg/kg body weight)		Body weight Day 0	Body weight Day 7	% body weight gain day 0-7	Body weight Day 14	% body weight gain day 7- 14	% body weight gain day 0- 14
I	2000	Mean	258.62	283.10	9.46	303.84	7.33	17.48
		± SD	5.70	6.54	0.57	7.88	1.51	1.35

Sex : Female

Group No.	Dose (mg/kg body weight)		Body weight Day 0	Body weight Day 7	% body weight gain day 0-7	Body weight Day 14	% body weight gain day 7- 14	% body weight gain day 0- 14
I	2000	Mean	230.04	241.18	4.84	252.74	4.79	9.86
		± SD	5.50	6.35	0.50	7.32	0.44	0.83

 

Table 4: Summary of Gross Pathological Findings

Sprague Dawley Rat

Sex : Male

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	2000	1 - 5	TS	No abnormality detected

Sex : Female

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	2000	6 - 10	TS	No abnormality detected

                     TS = Terminal Sacrifice

 

Interpretation of results:

other: Not classified

Conclusions:

The acute dermal LD50 value for test chemical can be considered to be >2000mg/kg bw. Hence, it was concluded that the acute toxicity of test chemical, when applied via dermal route in Sprague Dawley rats falls into the “Category Not classified” criteria of CLP.

Executive summary:

The study was designed and conducted to determine the acute dermal toxicity profile of test chemical in Sprague Dawley rats. The study was performed according to OECD 402 Guidelines. The test item was applied to shorn skin of 5 male and 5 female animals at 2000 mg/kg body weight. Administration of the test item at 2000 mg/kg did not result in any skin reaction at the site of application during the study period of 14 days. Administration of the test item did not result in any signs of toxicity and mortality during the study period of 14 days. Animals exhibited normal body weight gain through the study period of 14 days. No mortality or gross pathological abnormalities were observed in animals at the limit dose 2000 mg/kg bw. Therefore, the acute dermal LD50 value for test chemical can be considered to be >2000mg/kg bw. Hence, it was concluded that the acute toxicity of test chemical, when applied via dermal route in Sprague Dawley rats falls into the “Category Not classified” criteria of CLP.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

Data is Klimisch 1 and from experimental study report.

Additional information

Acute oral toxicity:

In different experimental studies, test chemical has been investigated for acute oral toxicity to a greater or lesser extent. Often are the studies based on in-vivo experiments in rodents, i.e. most commonly in rats and rabbits for test chemical. The studies are summarized as below –

The study was designed and conducted to determine the acute oral toxicity profile of test chemical in Sprague Dawley rats. The study was performed according to OECD 423 - Acute Toxic Class Method. Initially, three female animals were treated at the dose level of 300 mg/kg body weight of the test item (Group I Step I). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality at 24 hours after the dosing. As no mortality was observed at 24 hours after the dosing, three female animals were added to the study and treated with the same dose of 300 mg/kg of the test item (Group I Step II). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality after the dosing. As no mortality was observed at 300 mg/kg dose group, hence additional three female animals were treated with the higher dose of 2000 mg/kg of the test item (Group II Step I). Administration of the test item at 2000 mg/kg did not result in any signs of toxicity and mortality after the dosing. As no mortality were observed at 24 hours after the dosing, additional three female animals were treated with the higher dose of  2000 mg/kg of the test item (Group II Step II). Administration of the test item at 2000 mg/kg did not result in any signs of toxicity and mortality after the dosing. No mortality or gross pathological abnormalities were observed in animals from 300 mg/kg and 2000 mg/kg dose groups. Therefore, the acute oral LD50 value for test chemical Ethyl Butyrate (CAS No. 105-54-4) can be considered to be >2000mg/kg. Hence, it was concluded that the acute toxicity of test chemical when administered via oral route in Sprague Dawley rats falls into the “Category Not classified” criteria of CLP.

The above experimental study is supported with the study mentioned in different sources, for the test chemical . Acute oral toxicity study was conducted in groups of 10 male and female Osborne-Mendel rats at the dose concentration range of 12210-13940 mg/kg bw. The test chemical (undiluted) was administered via oral gavage route. All animals were maintained under close observation for recording toxic signs and time of death for 14 days. Such observation was continued until animals appeared normal and showed weight gain. LD50’s were computed by the method of Litchfield & Wilcoxon (1949). Death occurred within 4 to 18 hours. Depression showed within a few minutes, with coma on higher doses. Therefore, LD50 value was considered to be 13050 mg/kg bw, with 95% confidence limits of 12210-13940 mg/kg bw, when groups of 10 male and female Osborne-Mendel rats were treated with test chemical via oral gavage route.

Both the above experimental studies are further supported with the study mentioned.The acute oral toxicity study was conducted in 10-35 male and female rabbits at the dose concentration of 5228 mg/kg bw. The test chemical was dissolved in saline and administered via oral gavage route. 50% mortality was observed in treated animals. Therefore, LD50 value was considered to be 5228 mg/kg bw, when 10-35 male and female rabbits were treated with test chemical via oral gavage route.

Thus, based on the above experimental studies on test chemical, it can be concluded that LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, test chemical cannot be classified for acute oral toxicity.

Acute Inhalation Toxicity:

Data available for the structurally and functionally similar read across chemicals has been reviewed to determine the acute inhalation toxicity of the test chemical.The studies are as mentioned below:

1. Acute inhalation toxicity study of test chemical was conducted in 10 male and female Sprague-Dawley rats at the dose concentration of 7380 mg/m3 (7.38 mg/l). The exposure was given to whole body, respirable aerosol in clean dried air produced by aerosol generator (equilibration period 9 min), and exposure chamber 120 l with 10 separate animal compartments. The control animals received clean air only. Animals were observed for - clinical signs: continuously during exposure, twice daily during the observation period; body weights: daily; Food and water consumption per cage. Necropsy of survivors was performed. Macroscopic organ examination at necropsy and lung weights was done. No mortality was observed at 7380 mg/m3.During observation period, immediately after removal from the exposure chamber: exaggerated respiratory movements and matted fur (all rats), wet fur around the snout and jaws (2 males) and clear discharge from the eyes (3 females), brown staining around the snout and jaws (1 female) were observed. All symptoms were reversible within 24 hours. Slightly reduced body weight and food consumption on day 1, thereafter comparable to control. Water consumption not affected. At necropsy there were no macroscopic abnormalities in the rats. Lung to body weight ratio were comparable between test and control animals. Therefore, LC50 value was considered to be >7380 mg/m3, when 10 male and female Sprague-Dawley rats were treated with test chemical via inhalation route by aerosol to whole body exposure for 1 hour.

2. The acute inhalation toxicity study was conducted by using test chemical in rats at the concentration of 4000 ppm. No mortality was observed at 4000 ppm. Hence, LC50 value was considered to be >4000 ppm, when rats were exposed to test chemical via inhalation route.

Thus, based on the above summarised studies, test chemical and it’s structurally and functionally similar read across substances, it can be concluded that LC50 value is >5 mg/L. Thus, comparing this value with the criteria of CLP regulation, test chemical cannot be classified for acute inhalation toxicity.

Acute Dermal toxicity:

In different experimental studies, test chemical has been investigated for acute dermal toxicity to a greater or lesser extent. Often are the studies based on in vivo experiments in rodents, i.e. most commonly in rats and rabbits for test chemical. The studies are summarized as below –

The study was designed and conducted to determine the acute dermal toxicity profile of test chemical in Sprague Dawley rats. The study was performed according to OECD 402 Guidelines. The test item was applied to shorn skin of 5 male and 5 female animals at 2000 mg/kg body weight. Administration of the test item at 2000 mg/kg did not result in any skin reaction at the site of application during the study period of 14 days. Administration of the test item did not result in any signs of toxicity and mortality during the study period of 14 days. Animals exhibited normal body weight gain through the study period of 14 days. No mortality or gross pathological abnormalities were observed in animals at the limit dose 2000 mg/kg bw. Therefore, the acute dermal LD50 value for test chemical can be considered to be >2000mg/kg bw. Hence, it was concluded that the acute toxicity of test chemical, when applied via dermal route in Sprague Dawley rats falls into the “Category Not classified” criteria of CLP.

The above experimental study is supported with the study mentioned in publication, handbook and authoritative databases, for the test chemical. The acute dermal toxicity study was conducted in rabbits at the dose concentration of 2000 mg/kg bw. No mortality was observed at 2000 mg/kg bw. Therefore, LD50 value was considered to be >2000 mg/kg bw, when rabbits were treated with test chemical by dermal application.

Thus, based on the above experimental studies on test chemical, it can be concluded that LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation,test chemical cannot be classified for acute dermal toxicity.

Justification for classification or non-classification

Based on the above experimental studies on test chemical and it’s structurally and functionally similar read across substances, it can be concluded that LD50 value is >2000 mg/kg bw, for acute oral and acute dermal toxicity; and LC50 value is >5 mg/L, for acute inhalation toxicity. Thus, comparing these values with the criteria of CLP regulation, test chemical cannot be classified for acute oral, acute dermal and acute inhalation toxicity.