Ethyl hexanoate

Endpoint summary

Description of key information

The test item has a low acute toxicity by the oral and dermal route.

In rats, the LD50 value via the oral route is > 5000 mg/kg bw (value derived from Read -across compound Iso amyl isovalerate). In consideration of the molecular weight of both substances (172.27 and 144.21 g/mol), the corrected LD50 for the Ethyl caproate is > 4185.6 mg/kg.

In rats, the LD50 value via the dermal route is > 2000 mg/kg bw (value derived from Read -across compound Ethyl propionate). In consideration of the molecular weight of both substances (144.21 and 102.13 g/mol), the corrected LD50 for the target substance is > 2824 mg/kg.

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:

2016-03-16 to 2016-07-06

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)

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Remarks:

Crl:CD (SD), SPF

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 8 weeks old
- Weight at study initiation: 176.3-195.3 g
- Fasting period before study:animals were fasted overnight, approximately 16 hours prior to dosing
- Housing:cage in an animal room
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: for four days after three days of quarantine (including health examiniation)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.5-24.0 °C (measured), permissible range 19-25 °C
- Humidity (%): 43.5-58-5% (measured) permissible range 30-70 %
- Air changes (per hr): 10-15 clean, fresh, filterd air changes per hour
- Photoperiod (hrs dark / hrs light): 12 hours light/12 hours dark

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 500 mg/mL
- Lot/batch no. (if required): MKBS6944V

MAXIMUM DOSE VOLUME APPLIED: 10 ml/kg

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: due to the low expected toxicity of the test substance a starting dose of 5,000 mg/kg was selected.

Doses:

Step 1: starting dose of 5,000 mg/kg test substance was administered to one animal
Step 2: two animals were administered the test substance at 5,000 mg/kg, because there was no dead animal at 5,000 mg/kg (step 1)

No. of animals per sex per dose:

Step 1 : 1 animal
Step 2: 2 animals

Control animals:

no

Details on study design:

- Duration of observation period following administration:14 days
- Frequency of observations and weighing: observations for mortality, clinical signs, general conditions at 30 minutes after dosing and at 1,2,4,6 hours after dosing on day 0 and once daily thereafter for 14 days; body weight was recorded prior to dosing on day 0 and on day 1, 3,7, and on day of necropsy, day 14
- Necropsy of survivors performed: yes
- Other examinations performed: no histopathology, since no gross findings were obsereved at necropsy.

Statistics:

Statistical analysis was not performed. Mean scores and values are determined.

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

All animals at 5,000 mg/kg survived the duration of the study. There were no effects on the mortality. Refer to Table 1.

Clinical signs:

other: Mucous stool was observed in one animal at 5,000 mg/kg on Day 1 after dosing and it disappeared on Day 2 after dosing. Therefore, it was considered to be a test substance-related temporary change. Refer to table 2.

Gross pathology:

No gross visible evidence of morphological abnormalities was observed in any animal at 5,000 mg/kg.

Table 1: Summary of Mortality

Step / Dose (mg/kg)	No. of animals	Days after dosing															Mortality
		0	1	2	3	4	5	6	7	8	9	10	11	12	13	14
Step 1/ 5,000	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0/1
Step 2/ 5,000	2	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0/2

 

Table 2: Individual Clinical Signs

Step / Dose (mg/kg)	Animal ID	Clinical sign	Hours (Day 0) after dosing
			0.5	1	2	4	6
Step 1/ 5,000	2101		-	-	-	-	-
Step 2/ 5,000	2201		-	-	-	-	-
	2202		-	-	-	-	-

 

Step / Dose (mg/kg)	Animal ID	Clinical sign	Days after dosing
			0	1	2	3	4	5	6	7	8	9	10	11	12	13	14
Step 1/ 5,000	2101		-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
Step 2/ 5,000	2201		-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
	2202	Mucous stool	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-

-: No observable abnormality

+: Observable abnormality

Table 3. Individual Body Weights

Step/Dose (mg/kg)	Animal ID	Days after dosing					Gain 0 ~ 14
		0	1	3	7	14
Step 1 5,000	2101	176.3	185.9	202.0	212.9	234.9	58.6
Step 2 5,000	2201	184.6	193.8	213.4	223.8	227.5	42.9
	2202	195.3	198.9	214.1	228.6	235.5	40.2
	Mean	190.0	196.4	213.8	226.2	231.5	41.6
	S.D.	7.6	3.6	0.5	3.4	5.7	1.9
	N	2	2	2	2	2	2

 

 

Table 4. Individual Body Weights during an Acclimation Period

Animal ID	Temporary Animal ID	Receipt	Group assignment
2101	2002	170.9	198.0
2201 2202	2001	174.3	192.5
	2004	180.4	204.4
	2003	183.9	211.3
	Mean	177.4	201.6
	S.D.	5.9	8.1
	N	4	4

 

 

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the result of the acute oral toxicity study in Sprague-dawley rats, the test substance has an LD50 value >5000 mg/kg bw. Therefore, it was not classified according to CLP.

Executive summary:

The purpose of this study was to assess the potential toxicity of the test substance following a single oral dose administration to female Sprague-Dawley rats and to classify the test substance under GHS classification.

 

Two dose groups were designed as Steps 1 and 2 at 5,000 mg/kg. Step 1 consisted of one female and Step 2 consisted of two females. All animals were monitored for clinical signs and body weight changes during the 14-day observation period after administration. They were subjected to gross necropsy at the end of the observation period.

 

There were no deaths of animals at 5,000 mg/kg. Mucous stool was observed in an animal on Day 1 after dosing and it disappeared on Day 2 after dosing. A tendency to suppress body weight gain was observed in animals on Day 1 after dosing. Then, these animals returned to normal on Day 3. No test substance-related effects were observed in the necropsy in any animal.

 

Based on the result of the acute oral toxicity study in Sprague-Dawley rats, the test substance was not classified according to the GHS classification and the median lethal dose derived was: LD50 cut off> 5,000 mg/kg b.w.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

4 185.6 mg/kg bw

Quality of whole database:

The key study has been identified as reliability 1: reliable without restrictions. However, these data have been scored as reliability 2: reliable with restrictions when used for read across to the target test substance. The supporting study, based on the test substance, has been identified as reliability 4, due to the limited available data.

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

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:

2016-11-03 to 2017-02-17

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

The read across justification is included as an attachment to section 13.

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: Males 8 weeks old; Females 9 weeks old
- Weight at study initiation: Males 267.5-283.4g; Females 217.6-231.5g
- Housing: one animal per cage
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: four days after three days of quarantine (including health examinations)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.1-24.6°C (measured), permissible range 19.0-25.0°C
- Humidity (%): 47.7-61.7% (measured), permissible range 30.0-70.0%
- Air changes (per hr): 10-15 clean, fresh, filtered air changes per hour
- Photoperiod (hrs dark / hrs light): 12 hours light/12 hours dark

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: dorsal surface
- % coverage: 5 cm x 6 cm
- Type of wrap if used: lint, Soft Cloth Tape with Liner and surgical tape

REMOVAL OF TEST SUBSTANCE
- Washing (if done): cotton moistened with tepid water
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2.25 mL/kg bw

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5 animals per sex per dose

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: observations for mortality, clinical signs, general conditions at 30 minutes after dosing and at 1, 2, 4, 6 hours after dosing on day 0 and once daily thereafter for 14 days; body weight was recorded prior to dosing on day 0 and on day 3, 7, and on day of necropsy, day 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, no histopathology, since no gross findings were observed at necropsy.

Statistics:

Statistical analysis was performed using SAS progam V9.3.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

All animals at 2000 mg/kg bw survived the duration of the study. There were no effects on mortality (see table 1).

Clinical signs:

other: All animals at 2000 mg/kg bw and in the control group showed no clinical signs (see table 2).

Gross pathology:

No gross findings were observed in any animal at 2000 mg/kg bw.

Table 1: Summary of Mortality

Sex	dose (mg/kg)	No. animals	Days after dosing															mortality
			0	1	2	3	4	5	6	7	8	9	10	11	12	13	14
male	0	5	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0/5
	2000	5	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0/5
Female	0	5	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0/5
	2000	5	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0/5

Table 2: Individual Clinical Signs

Sex	Dose (mg/kg)	No. animals	Clinical sign	Hours (day 0) after dosing
				0.5	1	2	4	6
Male	0	5	NOA	5	5	5	5	5
	2000	5	NOA	5	5	5	5	5
Female	0	5	NOA	5	5	5	5	5
	2000	5	NOA	5	5	5	5	5

Sex	Dose (mg/kg)	No. animals	Clinical sign	Days after
				1	2	3	4	5	6	7	8	9	10	11	12	13	14
Male	0	5	NOA	5	5	5	5	5	5	5	5	5	5	5	5	5	5
	2000	5	NOA	5	5	5	5	5	5	5	5	5	5	5	5	5	5
Female	0	5	NOA	5	5	5	5	5	5	5	5	5	5	5	5	5	5
	2000	5	NOA	5	5	5	5	5	5	5	5	5	5	5	5	5	5

NOA: No observable abnormality

Table 3: Individual Body Weights

Sex	Dose		Days after dosing				Gain
			0	3	7	14	0-14
Male	0	Mean	274.9	288.3	315.7	358.1	83.2
		S.D.	3.2	1.9	6.9	12.8	12.4
		N	5	5	5	5	5
	2000	Mean	276.0	284.1	305.2	344.9	68.9
		S.D.	6.8	10.2	12.1	18.9	14.1
		N	5	5	5	5	5
Female	0	Mean	225.5	228.0	237.2	248.4	22.9
		S.D.	4.9	3.2	7.5	14.0	10.0
		N	5	5	5	5	5
	2000	Mean	226.3	227.6	239.2	254.4	28.2
		S.D.	7.0	2.4	4.4	5.2	8.7
		N	5	5	5	5	5

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the result of the acute dermal study in Sprague-Dawley rats, the test substance has an LD50 of > 2000 mg/kg bw. Therefore, the target substance was not classified according to CLP classification.

Executive summary:

The purpose of this study was to assess the potential toxicity and the approximate LD50 value of the test substance, following a single dermal application to Sprague-Dawley rats.

 

Test groups consisted of one dose group at a dose of 2,000 mg/kg and a control group, and each group consisted of 5 males and 5 females. All animals were monitored for clinical signs and body weight changes after dosing during the 14-day observation period. They were subjected to gross necropsy at the end of the observation period.

 

There were no deaths of animals in the 2,000 mg/kg groups. No test substance-related effects were observed in clinical signs, body weight data or necropsy findings in the 2,000 mg/kg groups. Based on the result of this study, the LD50 value of the test substance was considered to be greater than 2,000 mg/kg in male and female rats under the conditions of this study.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 824 mg/kg bw

Quality of whole database:

The key source study has been identified as reliability 1: reliable without restrictions. However, these data have been scored as reliability 2: reliable with restrictions when used for read across to the target test substance. The supporting study, based on the test substance, has been identified as reliability 4, due to the limited available data.

Additional information

In the supporting acute oral toxicity study an LD50 of >5000 mg/kg bw in rats was determined.

In the supporting acute dermal toxicity study an LD50 of >5000 mg/kg bw in rabbits was determined.

Based on the available information these studies were selected as supporting studies as they are insufficiently documented and therefore less reliable.

Justification for classification or non-classification

Based on the available results, the test substance is not classified under CLP for acute oral and dermal toxicity according to Regulation (EC) No 1272/2008.