Pentyl formate

Endpoint summary

Description of key information

Acute oral toxicity:

LD50 was considered to be > 2000 mg/kg bw when rat were treated with Pentyl formate orally.

Acute dermal toxicity:

LD50 was considered to be > 2000 mg/kg bw when rabbits were treated with Pentyl formate dermally.

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:

13-10-2017 to 1-11-2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Principles of method if other than guideline:

Acute oral toxicity of Pentyl formate on rats according to OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

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
- Age at study initiation: Female rats of the age of approximately 8 to 12 weeks old were used at the commencement of its dosing
- Weight at study initiation: Body weight range was 194.3 to 206.4 grams.
Body weights at the start :
Female
Mean : 200.31 g (= 100 %)
Minimum : 194.3 g (- 3.00 %)
Maximum : 206.4 g (+ 3.04 %)
Total No. of animals : 12
- Identification: Each female rat was individually identified by the picric acid marking.
- Fasting period before study: Approximately 16 hours or more.
- Housing: The rats were housed in 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: 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20.0 to 22.0 degree centigrade.
- Humidity (%): 55.0% to 59.3%.
- Air changes (per hr): Ten to fifteen air changes per hour.
- Photoperiod (hrs dark / hrs light): An artificial light and dark cycle of 12 hours each was provided to the room.

IN-LIFE DATES: 13-10-2017 to 01-11-2017

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 300 mg/kg, 300 mg/kg, 2000 mg/kg and 2000 mg/kg
- Amount of vehicle (if gavage): No data available
- Justification for choice of vehicle: No data available
- Lot/batch no. (if required): No data available
- Purity: No data available

MAXIMUM DOSE VOLUME APPLIED: 10 ml/kg body weight.

DOSAGE PREPARATION (if unusual): No data available

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: No data available

Doses:

Dose Group I : 300 mg/kg
Dose Group I : 300 mg/kg
Dose Group II : 2000 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: Twice daily
- Necropsy of survivors performed: Yes
- Other examinations performed:
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:

No data

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other:

Remarks:

No mortality observed

Mortality:

Group I
Step I :
Animals treated at the dose level of 300 mg/kg body weight: All animals survived through the study period of 14 days.

Group I
Step II :
Animals treated at the dose level of 300 mg/kg body weight: All animals survived through the study period of 14 days.

Group II
Step I :
Animals treated at the dose level of 2000 mg/kg body weight: All animals survived through the study period of 14 days.

Group II
Step II :
Animals treated at the dose level of 2000 mg/kg body weight: All animals survived through the study period of 14 days.

Clinical signs:

other: Group I Step I : Animals treated at the dose level of 300 mg/kg body weight did not result in any signs of toxicity during the study period of 14 days. Group I Step II : Animals treated at the dose level of 300 mg/kg body weight did not result in any

Gross pathology:

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

Other findings:

No data available

Table No. I

Summary of Clinical Signs of Toxicity and Mortality

Test System : 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 No.II

Mean Body Weight and Percent Body Weight Gain (g)

Test System : 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	197.70	212.40	7.43	8.47	6.41	16.53
		± SD	2.96	3.61	5.38	0.75	0.20	1.47

 

 

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	199.27	213.07	6.92	230.87	8.36	15.86
		± SD	3.52	4.50	0.75	3.99	0.51	0.35

 

 

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	200.33	214.33	6.98	231.53	8.02	15.57
		± SD	1.53	3.66	1.08	5.10	0.77	1.86

 

 

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	203.93	216.97	6.39	234.17	7.92	14.82
		± SD	2.16	2.47	0.63	4.72	0.95	1.46

 

 

Table No.III

Summary of Gross Pathological Findings

Test System : 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:

Under the condition of the study, the acute oral LD50 of Pentyl formate (CAS No. 638-49-3) was >2000 mg/kg body weight. Thus, it was concluded that the acute toxicity study of Pentyl formate (CAS No. 638-49-3), when administered via oral route in Sprague Dawley rats falls into the “Category Not classified” criteria of CLP.

Executive summary:

The study now reported was designed and conducted to determine the acute oral toxicity profile of Pentyl formate (CAS No. 638-49-3) in Sprague Dawley rats.

Initially, three female animals were treated at the dose level of 300 mg/kg body weight of the test item (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 (Step - II). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality after the dosing.

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 (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 (Step - II). Administration of the test item at 2000 mg/kg did not result in any signs of toxicity and mortality after the dosing.

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

The acute oral LD50 of Pentyl formate (CAS No. 638-49-3) was >2000 mg/kg body weight.

Thus, it was concluded that the acute toxicity study of Pentyl formate (CAS No. 638-49-3), 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 study report

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

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:

11-09-2017 to 28-12-2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Data is from study report

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Principles of method if other than guideline:

This study was designed to determine the dermal LD50 of the test item (up to 2000 mg/kg) or to establish a non-lethal dose level of 2000 milligram of test item per kilogram of body weight.

GLP compliance:

yes

Test type:

other: Acute dermal toxicity

Limit test:

no

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
- Age at study initiation: Young adult (8 to 10 weeks old) female rats were used.
- Weight at study initiation: The weight range of approximately 218.0 to 246.5 grams at initiation of dosing.
Body weights at the start : Female - Mean: 231.16 g (= 100 %); Minimum : 218.0 g (- 5.69 %); Maximum : 246.5 g (+ 6.64 %)
- Identification: Each rat was individually identified by the cage number.
- Housing: The rats were individually housed in polycarbonate cages with paddy husk as bedding.
- Diet (e.g. ad libitum): Rodent feed 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: 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19.2 to 21.8 degree centigrade.
- Humidity (%): 56.0% to 59.1%.
- Air changes (per hr): Ten to fifteen air changes per hour.
- Photoperiod (hrs dark / hrs light): An artificial light and dark cycle of 12 hours each was provided to the room.

IN-LIFE DATES: 11-09-2017 to 28-12-2017

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: the trunk (dorsal surface and sides from scapular to pelvic area)
- % coverage: approximately 10% of the total body surface area
- Type of wrap if used: The test item was held in contact with the skin using a porous gauze dressing and non irritating tape around the animal to cover the exposure site. Elizabethan collar was placed on each animal for first 24 hours after application of the test item. These collars prevent ingestion of test item.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): 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

Duration of exposure:

24 hours

Doses:

Dose Range Finding Study:
Group I : 200 mg/kg
Group I : 1000 mg/kg
Group I : 2000 mg/kg
Main Study: Group II : 2000 mg/kg

No. of animals per sex per dose:

Dose Range Finding Study:
Group I : 200 mg/kg - 1
Group I : 1000 mg/kg - 1
Group I : 2000 mg/kg - 1
Main Study: Group II : 2000 mg/kg - 2

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Twice daily
- Necropsy of survivors performed: yes, 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).
- Other examinations performed: 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 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.
Histopathology:
No gross abnormalities were observed in animals sacrificed terminally hence, no histopathology was performed.

Statistics:

not specified

Preliminary study:

Dose Finding Study: A single dose of 200 mg/kg body weight of the test item was administered to 1 female animal. No death or clinical signs of toxicity was observed during first 48 hours, hence, additional 1 female animal was administered at the dose of 1000 mg/kg body weight. Administration of 1000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours, hence, additional 1 female animal was administered at the dose of 2000 mg/kg body weight. Administration of 2000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours.

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

Dose Range Finding Study: All animals survived through the study period of 14 days at 200 mg/kg, 1000 mg/kg and 2000 mg/kg body weight .
Main Study: Group II : All animals survived through the study period of 14 days.

Clinical signs:

other: Dose Range Finding Study: Animals treated at the dose level of 200 mg/kg, 1000 mg/kg and 2000 mg/kg body weight did not result in any signs of toxicity during the study period of 14 days. Main Study: Group II : Animals treated at the dose level of 2000 m

Gross pathology:

Gross pathological examination did not reveal any abnormalities in animals from 200 mg/kg, 1000 mg/kg and 2000 mg/kg dose groups from dose range finding study and main study sacrificed terminally.

Other findings:

Dose Range Finding Study: Group I : Animal treated at the dose level of 200 mg/kg body weight did not result in any skin reaction during the study period of 14 days.
Group I : Animal treated at the dose level of 1000 mg/kg body weight did not result in any skin reaction during the study period of 14 days.
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.
Main Study: Group II : Animals 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 No. I

Summary of Clinical Signs of Toxicity and Mortality

 

Laboratory Test Item Code :TAS/122/055

Test System : Sprague Dawley Rat

Sex : Female

Dose Finding Study:

Group  No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	200	No clinical signs observed	1	1	Day 0 - Day 14	0/1

 

Group  No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	1000	No clinical signs observed	1	2	Day 0 - Day 14	0/1

 

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	1	3	Day 0 - Day 14	0/1

 

Main Study:

Group  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	2	4, 5	Day 0 - Day 14	0/2

Table No. II 

Summary of Evaluation of Dermal Reaction

 

Laboratory Test Item Code :TAS/122/055

Test System : Sprague Dawley Rat

Sex : Female

Dose Finding Study:

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to
I	200	No dermal reaction observed	1	1	Day 0 - Day 14

 

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to
I	1000	No dermal reaction observed	1	2	Day 0 - Day 14

 

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to
I	2000	No dermal reaction observed	1	3	Day 0 - Day 14

 

Main Study:

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to
II	2000	No dermal reaction observed	2	4, 5	Day 0 - Day 14

 

Table No.III

Mean Body Weight and Percent Body Weight Gain (g)

 

Laboratory Test Item Code :TAS/122/055

Test System : Sprague Dawley Rat

Sex : Female

Dose Finding Study:

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	200	Mean	233.3	245.1	5.06	257.0	4.86	10.16
		± SD	-	-	-	-	-	-

 

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	1000	Mean	218.0	230.8	5.87	240.9	4.38	10.50
		± SD	-	-	-	-	-	-

 

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	224.5	233.0	3.79	245.6	5.41	9.40
		± SD	-	-	-	-	-	-

Main Study:

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
II	2000	Mean	240.00	251.10	4.64	257.15	2.39	7.13
		± SD	9.19	7.92	0.71	11.24	1.25	0.58

Table No.IV

Summary of Gross Pathological Findings

 

Laboratory Test Item Code :TAS/122/055

Test System : Sprague Dawley Rat

Sex : Female

Dose Finding Study:

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	200	1	TS	No abnormality detected

 

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	1000	2	TS	No abnormality detected

 

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	2000	3	TS	No abnormality detected

 

                    Main Study:

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
II	2000	4, 5	TS	No abnormality detected

 

                     TS = Terminal Sacrifice

Interpretation of results:

other: Not classified

Conclusions:

It was concluded that the acute dermal median lethal dose (LD50) of the given test chemical, when administered to female Sprague Dawley rats was considered to be >2000 mg/kg body weight. Thus, according to CLP criteria for acute toxicity rating for the chemicals, it infers that the given test chemical does not classify as an acute dermal toxicant. CLP Classification: “Not classified”.

Executive summary:

The reported study was designed and conducted to determine the acute dermal toxicity profile of Pentyl formate (CAS No. 638-49-3) as per OECD Guideline 402 (Acute Dermal Toxicity) in Sprague Dawley rats.

In the dose range finding study a single dose of 200 mg/kg body weight of the test item was administered to 1 female animal. No death or clinical signs of toxicity was observed during first 48 hours, hence, additional 1 female animal was administered with the dose of 1000 mg/kg body weight. Administration of 1000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours, hence, additional 1 female animal was administered at the dose of 2000 mg/kg body weight. Administration of 2000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours.

As the dose range finding study revealed no mortality or clinical signs at the maximum dose of 2000 mg/kg, the main study was initiated with two additional animals. The animals were administered with a dose of 2000 mg/kg body weight in sequential manner at 48 hours intervals.

Animals from dose range finding study treated at the dose levels of 200 mg/kg, 1000 mg/kg and 2000 mg/kg and animals from main study treated at the dose level of 2000 mg/kg exhibited normal body weight gain and revealed no clinical signs of toxicity or mortality during the study period of 14 days. Gross pathological examination did not reveal any abnormalities attributable to the treatment.

It was concluded that the acute dermal median lethal dose (LD50) of Pentyl formate (CAS No. 638-49-3), when administered to female Sprague Dawley rats was considered to be >2000 mg/kg body weight. Thus, according to CLP criteria for acute toxicity rating for the chemicals, it infers that Pentyl formate (CAS No. 638-49-3) does not classify as an acute dermal toxicant. CLP Classification: “Not classified”.

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 study report

Additional information

Acute oral toxicity:

In different studies, Pentyl formate 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 for Pentyl formate along with the study available.

The study reported was designed and conducted to determine the acute oral toxicity profile of Pentyl formate (CAS No. 638-49-3) in Sprague Dawley rats.

Initially, three female animals were treated at the dose level of 300 mg/kg body weight of the test item (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 (Step - II). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality after the dosing.

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 (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 (Step - II). Administration of the test item at 2000 mg/kg did not result in any signs of toxicity and mortality after the dosing.

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

The acute oral LD50 of Pentyl formate (CAS No. 638-49-3) was >5000 mg/kg body weight.

Thus, it was concluded that the acute toxicity study of Pentyl formate (CAS No. 638-49-3), when administered via oral route in Sprague Dawley rats falls into the “Category Not classified” criteria of CLP.

In a experimental study summarized, rat were treated with Pentyl formate in the concentration of 5000 mg/kg bw orally. No mortality was observed in treated rat at 5000 mg/kg bw. Therefore, LD50 was considered to be > 5000 mg/kg bw when rat were treated with Pentyl formate orally.

In another study, the acute oral toxicity was estimated for Pentyl formate. The LD50 was estimated to be 3500 mg/kg bw in rat and 2100 mg/kg bw when mice exposed orally with Pentyl formate.

Thus, based on the above studies and predictions on Pentyl formate and its read across substances and by applying weight of evidence, it can be concluded that LD50 value is greater than 2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, Pentyl formate can be Not classified as acute oral toxicity.

Acute dermal toxicity:

In different studies, Pentyl formate 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 rabbits.

The reported study was designed and conducted to determine the acute dermal toxicity profile of Pentyl formate (CAS No. 638-49-3) as per OECD Guideline 402 (Acute Dermal Toxicity) in Sprague Dawley rats.

In the dose range finding study a single dose of 200 mg/kg body weight of the test item was administered to 1 female animal. No death or clinical signs of toxicity was observed during first 48 hours, hence, additional 1 female animal was administered with the dose of 1000 mg/kg body weight. Administration of 1000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours, hence, additional 1 female animal was administered at the dose of 2000 mg/kg body weight. Administration of 2000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours.

As the dose range finding study revealed no mortality or clinical signs at the maximum dose of 2000 mg/kg, the main study was initiated with two additional animals. The animals were administered with a dose of 2000 mg/kg body weight in sequential manner at 48 hours intervals.

Animals from dose range finding study treated at the dose levels of 200 mg/kg, 1000 mg/kg and 2000 mg/kg and animals from main study treated at the dose level of 2000 mg/kg exhibited normal body weight gain and revealed no clinical signs of toxicity or mortality during the study period of 14 days. Gross pathological examination did not reveal any abnormalities attributable to the treatment.

It was concluded that the acute dermal median lethal dose (LD50) of Pentyl formate (CAS No. 638-49-3), when administered to female Sprague Dawley rats was considered to be >2000 mg/kg body weight. Thus, according to CLP criteria for acute toxicity rating for the chemicals, it infers that Pentyl formate (CAS No. 638-49-3) does not classify as an acute dermal toxicant. CLP Classification: “Not classified”.

Thus, based on the above studies on Pentyl formate, it can be concluded that LD50 value is greater than 2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, Pentyl formate can be Not classified as acute dermal toxicity.

Justification for classification or non-classification

Based on the above studies on Pentyl formate and its read across substances and by applying weight of evidence, it can be concluded that LD50 value is greater than 2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, Pentyl formate can be Not classified as acute oral and dermal toxicity.