Ethyl benzoate

Endpoint summary

Description of key information

oral:
The LD50 values determined on three studies on rabbits and rats are greater than 2000 mg/kg bw.
inhalation:
Ethyl benzoate was not toxic as concentrated vapour to rats in an 8 hour inhalation study.
dermal:
Several studies on different animal species revealed a LD50 of >2000 mg/kg bw.

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:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Well documented publication, the described study is conducted equivalent or similar to an OECD Guideline.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

not specified

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Species:

rabbit

Strain:

not specified

Sex:

not specified

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Fasting period before study: 24-48 hours

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Doses:

After preliminary orientation tests, four groups of three rabbits each were used in the range of LD50 +/- 0.5 g/kg bw.

No. of animals per sex per dose:

3

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: no data

Statistics:

no data

Key result

Sex:

not specified

Dose descriptor:

LD50

Effect level:

2 630 mg/kg bw

Based on:

test mat.

Clinical signs:

other: other: Signs of central nervous stimulation and prostration (12-24 hours) were observed in the rabbits before death.

Gross pathology:

no data

Interpretation of results:

GHS criteria not met

Conclusions:

Ethyl benzoate was administered to rabbits by gavage in three concentrations. As a result, the LD50 value was found to be 2630 mg/kg bw in rabbits.

Executive summary:

In this publication, a study is described which was conducted to assess the oral toxicity of ethyl benzoate in several animals including rabbits. Ethyl benzoate was administered to a total of 12 rabbits by gavage. Four rabbits each were exposed to one of three concentrations. These concentrations were in the range of the LD50 value +/- 0.5 g /kg bw determined by a preliminary toxicity study. As a result, the LD50 value was found to be 2630 mg/kg bw in rabbits.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The available studies used in this weight of evidence approach are sufficient for assessment.

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:

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

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

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study conducted in compliance with GLP and OECD Guideline.

Justification for type of information:

For justification of read across see section 13.

Reason / purpose for cross-reference:

read-across source

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:

rabbit

Strain:

New Zealand White

Sex:

male/female

Type of coverage:

not specified

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST MATERIAL
- Amount applied: 2000 mg/kg bw

Duration of exposure:

single exposure, test substance was not washed off afterwards

Doses:

one dose, 2000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Animals were weighted on days 1, 2, 4, 7 and 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, organ weights, histopathology

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred.

Clinical signs:

other: other: No treatment-related findings were recorded.

Gross pathology:

No abnormal findings were recorded.

Other findings:

- Other observations: Cysts in the oviduct were found in three females which were considered to be normal for this strain of rabbits and therefore not treatment-related.

Interpretation of results:

GHS criteria not met

Conclusions:

Methyl bezoate was tested for its dermal toxicity in 10 New Zealand White rabbits. It was shown that a single dose of 2000 mg/kg bw did not lead to any deaths, and therefore the LD 50 was found to be >2000 mg/kg bw.

Executive summary:

Methyl bezoate was tested for its dermal toxicity in 10 New Zealand White rabbits (5 males and 5 females). Therefore, a single dose of 2000 mg/kg bw was applied to the rabbits' skin. Loss of test substance was prevented by using a collar. The animals were weighted (on days 1, 2, 4, 7 and 14) and observed during the 14 -day observation period. No deaths occurred. The treated skin sites showed signs of irritaion. A decrease in body weights was observed in four male and three female rabbits on day 1 and one female showed a decrease in body weight during days 4 and 7. At necropsy, no treatment related findings were observed. Therefore, the LD50 after dermal application was found to be greater than 2000 mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The available studies used in this weight of evidence approach are sufficient for assessment.

Additional information

Acute toxicity

Oral route

Three studies are available for this endpoint and are used for a weight of evidence approach. In the first publication, a study is described which was conducted to assess the oral toxicity of ethyl benzoate in several animals including rabbits. Ethyl benzoate was administered to a total of 12 rabbits by gavage. Three concentrations were tested, each dose group consisted of 4 rabbits. As a result, the LD50 value was found to be 2630 mg/kg bw in rabbits.

 

In the second study which is described in the same publication the material was tested on rats. Ethyl benzoate was administered to a total of 45 rats by gavage. Five rats per group were exposed to one of nine concentrations. As a result, the LD50 value was found to be 2100 mg/kg bw in rats.

 

In the third publication an acute oral toxicity tests of ethyl benzoate and other substances in rats is described. Therefore, female Carworth-Wistar rats were used. The test substance was administered to five rats per dose group. The maximum dose volume did not exceed 10 mL. Rats were observed for a period of 14 days and deaths were recorded. As a result, the LD50 value of the test substance to female rats was determined to be 6480 mg/kg bw.

 

Inhalation route

As studies are available on acute toxicity by oral and dermal route, studies on the acute toxicity by inhalation do not need to be provided. But, as a publication is available, the results are nevertheless summarized. In this publication it is described how ethyl benzoate, among other substances, was tested for its acute toxicity after inhalation in rats. Therefore, female Carworth-Wistar rats were exposed to concentrated vapour of the test substance for 8 hours. As no deaths occured, it was concluded that the LD50 lies over the saturated vapour concentration of the test substance. Therefore the study revealed that ethyl benzoate is not toxic via inhalation and thus supports the waiving.

 

Dermal route

Several studies on different animal species are available analyzing the acute dermal toxicity of ethyl benzoate or read across substances. These studies were used in an weight of evidence approach.

 

As a read across substance methyl benzoate was tested for its dermal toxicity in 10 New Zealand White rabbits (5 males and 5 females). Therefore, a single dose of 2000 mg/kg bw was applied to the rabbits' skin. Loss of test substance was prevented by using a collar. The animals were weighted (on days 1, 2, 4, 7 and 14) and observed during the 14 -day observation period. No deaths occurred. The treated skin sites showed signs of irritation. A decrease in body weights was observed in four male and three female rabbits on day 1 and one female showed a decrease in body weight during days 4 and 7. At necropsy, no treatment related findings were observed. Therefore, the LD50 after dermal application was found to be greater than 2000 mg/kg bw.

 

To assess the acute dermal toxicity of ethyl benzoate, additionally a publication is available which describes a study conducted on cats. 20 mL of the substance were applied undiluted to the clipped backs of two cats. Both animals died after an average time of 20 hours. Before death, the animals exhibited excessive salivation, twitching of the treated area, generalized tremor, muscular incoordination, paralysis of the hind limbs, violent convulsions and respiratory failure. These results indicate that the LD50 dose lies under the dose applied, which was calculated to be 10000 mg /kg bw (far above the required limit dose for acute dermal toxicity testing) assuming a bodyweight of 2 kg.

 

Ethyl benzoate was also applied to the back of mice in another study. Four different concentrations were used: 10 %, 20 %, 50 % and 100 %. Acetone was used as a vehicle. 2 -4 mice of the same sex were used per dose. The test material was applied to 1/3 of the body surface. During a 7 days observation period, the skin temperature, survival, body weight , behaviour and food intake were observed. An autopsy was performed afterwards. As a result, the highest tolerable dose was found to be 10 %.

 

Additionally, ethyl benzoate was applied as an emulsion or solution to the whole body surface of calves at four different concentrations: 10 %, 20 %, 50 % and 100 %. The test animals were 5-6 months old. During a 15 days observation period, no deaths occurred and no other adverse effects were observed.

 

As another read across substance, isopropyl benzoate was applied on the skin of 5 rabbits per dose group. After a 14 days observation period the LD50 was determined to be >2000 mg/kg bw.

 

Additionally, a single dose of butyl benzoate was applied to the clipped skin of 10 rabbits (8 males and 2 females). The exposure site was occluded for 24 hours and afterwards wiped to remove excess material. Diarrhea was observed during the 14 days observation period. As no deaths occurred, the LD50 was determined to be >5000 mg/kg bw.

 

All these studies indicate an LD50 of >2000 mg/kg bw and therefore no acute dermal toxicity of the test substance.

 

Overall summary: The test item showed no acute oral, dermal and inhalation toxicity up the limit dose and above in rats and rabbits.

Justification for classification or non-classification

The available data gave no indications for acute toxic properties of the test substance either via oral or dermal route or via inhalation. On the basis of these data the substance is not considered to be classified for acute toxicity under Directive 67/548/EEC (DSD) or under Regulation (EC) No 1272/2008 (CLP).