1-phenylethyl acetate

Endpoint summary

Description of key information

The NOAEL for the 90-Day Repeated Dose Toxicity study on Gardenol dosed via the oral route was >= 150 mg/kg bw/day, the highest dose level in the study.

The NOAEL for the supporting structurally similar analogue benzyl acetate was 250 mg/kg bw/day for females and 500 mg/kg bw/day for males according to a study performed in line with methodology considered to be equivalent or similar to OECD Guideline 408.

 

Repeated Dose Toxicity studies: Dermal and Inhalation: Data waivers have been submitted to address repeat dose toxicity via the dermal and inhalatory routes. Exposure via the oral route is considered to be the most likely route of exposure and sufficient repeat dose oral toxicity studies have been submitted.

Key value for chemical safety assessment

Toxic effect type:

dose-dependent

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Reference 1

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1974

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was performed in line with good scientific principles to a method comparable to current standardised guidelines. A high level of detail was included in both the methods and the results.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity Study in Rodents)

Deviations:

no

GLP compliance:

not specified

Limit test:

no

Specific details on test material used for the study:

Name of test material: 1-phenylethyl acetate- Name of test material (as cited in study report): Methylphenylcarbinyl acetate- Physical state: colourless liquid- Analytical purity: 98 %- Specific gravity (25/25 °C): 1.023-1.026- Refractive index: 1.494-1.496

Species:

rat

Strain:

other: CFE

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS- Weight at study initiation: 82-115 g males, 68-104 g females- Housing: Five per cage- Diet: ad libitum- Water: ad libitumENVIRONMENTAL CONDITIONS- Temperature (°C): 21 ± 1 °C- Humidity (%): 50-60 %

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

VEHICLE- Amount of vehicle (if gavage): 5 mL/kg bw

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

13 weeks

Frequency of treatment:

Once a day, seven days a week

Dose / conc.:

15 mg/kg bw/day (actual dose received)

Dose / conc.:

50 mg/kg bw/day (actual dose received)

Dose / conc.:

150 mg/kg bw/day (actual dose received)

No. of animals per sex per dose:

15 males and 15 females per group dosed for the entire 13 weeks, additionally, five rats of each sex were dosed with the 0, 50 or 150 mg/kg bw/day for 2 or 6 weeks.

Control animals:

yes, concurrent vehicle

Positive control:

NA

Observations and examinations performed and frequency:

CLINICAL OBSERVATIONS: YesBODY WEIGHT: Yes- Time schedule for examinations: Recorded weeklyFOOD CONSUMPTION: Recorded 24 hours prior to weighing- Food consumption for each animal determined and mean daily diet consumption calculated as g food/rat/day: Yes WATER CONSUMPTION: Yes- Time schedule for examinations: Recorded 24 hours prior to weighingHAEMATOLOGY: Yes, at the end of each exposure period, animals were scarified by exsanguination under barbiturate anaesthesia- Time schedule for collection of blood: Blood was collected from the aorta at sacrifice- Animals fasted: Yes, 24 hours- Parameters checked: Haemoglobin, packed cell volume, red blood cells, reticulocytes, neutrophils, eosinophils, lymphocytes and monocytesCLINICAL CHEMISTRY: Yes, at the end of each exposure period, animals were scarified by exsanguination under barbiturate anaesthesia- Time schedule for collection of blood: Blood was collected from the aorta at sacrifice- Animals fasted: Yes, 24 hours- Parameters checked: Urea, glucose and activities of glutamic—oxalacetic transaminase, glutamic-pyruvic transaminase and lactic dehydrogenaseURINALYSIS: Yes- Time schedule for collection of urine: During the final week of treatment.- Parameters checked: Appearance, microscopic constituents and content of glucose, ketones, bile salts and blood were examined. A renal concentration test was also performed. At week 6 and 13, the specific gravity and volume of the urine produced during a 6 hour period of water deprivations, during a 2 hour period following a water load of 25 mL/kg and from 16-20 hours after the water load. At week 2, these measurements were only made during a 6 hour deprivation period. A count of the number of cells in in the urine was carried out with the 6 hour urine sample.

Sacrifice and pathology:

GROSS PATHOLOGY: YesThe following were weighed and examined grossly for macroscopic alterations: brain, pituitary, thyroid, heart, liver, stomach, small intestine, caecum, spleen, kidneys, adrenal glands and gonads.HISTOPATHOLOGY: Yes, the aforementioned tissues that underwent macroscopic examination were also prepared for microscopic examination along with samples of salivary gland, trachea, aorta, lung, lymph nodes, urinary bladder, colon, rectum, pancreas, uterus and skeletal muscle.

Statistics:

Effects were assessed for statistical significance

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

Food consumption was slightly increased in males treated with 150 mg/kg/day.

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

no effects observed

Description (incidence and severity):

Water consumption was slightly increased in males treated with 150 mg/kg/day.

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

no effects observed

Description (incidence and severity):

Cell excretion was 7.3 x 10³/hr at week 6 in males given 150 mg/kg/day compared with 4.3 x 10³/hr in the control group.

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

Increased stomach weights seen in 50 and 150 mg/kg/day females at 2 weeks. Testes weights decreased in treated males at week 6.
At 13 weeks mean relative liver and kidney weights were increased in the 150 mg/kg/day males (not statistically significant).

Gross pathological findings:

no effects observed

Description (incidence and severity):

Thickening of the pericardium and an adhesion between the heart and pericardium were noted in a female dosed with 50 mg/kg/day.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

no effects observed

Description (incidence and severity):

Histopathological findings were not considered to be related to the toxicity of the test substance.

Histopathological findings: neoplastic:

no effects observed

Description (incidence and severity):

One control female killed after 6 weeks had multiple small nodules in the lung (reticulum-cell neoplasm type A).

Other effects:

not specified

Details on results:

CLINICAL SIGNS AND MORTALITYNo behavioural or obvious clinical symptoms were noted in the animals during the course of the study. The two deaths noted in the study were due to accidental intratracheal administration and not attributed to the toxicity of the test substance.BODY WEIGHT AND WEIGHT GAINNo statistically significant differences noted in the study. In the group of animals with the lower testes weight occurred in animals with lower bodyweights.FOOD CONSUMPTIONFood consumption was slightly increased in males receiving 150 mg/kg/day.WATER CONSUMPTIONFood consumption was slightly increased in males receiving 150 mg/kg/day.HAEMATOLOGYNo statistically significant differences.CLINICAL CHEMISTRYNo statistically significant differences.URINALYSISRenal dilution and concentration results did not indicate any significant differences between treated and control animals and no abnormal constituents were noted. Cell excretion was 7.3 x 10³/hour at week 6 in males given 150 mg/kg/day compared with 4.3 x 10³/hour in the control group, this was 70 % higher than controls, however no similar effects were noted in any other group.ORGAN WEIGHTSIncreased stomach weights were seen in 50 and 150 mg/kg/day females at 2 weeks. Testes weights were decreased in treated males at week 6. These were not found to be significant when expressed as relative to bodyweight. At 13 weeks mean relative liver and kidney weights were increased in the 150 mg/kg/day males (not statistically significant). This was considered to be an increase enzyme activity in the liver, metabolising the test substance (coping mechanism) rather than a toxic effect of the test substance. These differences were not accompanied by histopathological changes.GROSS PATHOLOGYOne female in the 50 mg/kg/day at 13 weeks had thickening of the pericardium and an adhesion between the heart and pericardium.HISTOPATHOLOGY: NON-NEOPLASTICIn the female with the thickening of the pericardium, oil droplets were noted in the thoracic cavity, pericarditis and a granulomatous reaction of the pericardium containing oil droplets were noted. One male dosed with 15 mg/kg/day (13 weeks) also demonstrated similar effects. These were considered to be due to misadministration of the dose (intratracheal).Evidence of a mild pulmonary infection, early changes characteristic of glomerulonephrosis and splenic haemosiderin deposition were recorded, however these effects were also noted in the control with comparable severity. Two females in the 150 mg/kg/day groups (13 weeks) also had hydrometra in the uteri.HISTOPATHOLOGY: NEOPLASTICOne control female killed after 6 weeks had multiple small nodules in the lung (reticulum-cell neoplasm type A).

Key result

Dose descriptor:

NOEL

Effect level:

15 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

food consumption and compound intake

water consumption and compound intake

other: slight increase in liver and kidney weights

Remarks on result:

other:

Remarks:

No effects on histopathology for both liver and kidney

Key result

Dose descriptor:

NOAEL

Effect level:

150 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: food consumption;water consumption and organ weights

Remarks on result:

other:

Remarks:

No effects on histopathology for both liver and kidney. Effects considered adaptive.

Key result

Critical effects observed:

no

Table 1: Results for bodyweight and food and water consumption

Dose level (mg/kg)

Bodyweight (g) at day

Bodyweight gain (g) at day 95

Mean food consumpation (g/rat/day)

Mean water consumpation (mL/rat/day)

0

32

60

95

Males

0

101

287

376

432

331

16.1

22.3

15

101

288

368

429

328

15.9

22.9

50

104

302

383

446

342

16.4

23.4

150

103

302

381

447

344

17.5**

24.5*

Females

0

88

194

231

258

170

13.4

19.4

15

89

199

241

260

171

13.4

19.8

50

91

203

238

265

174

12.5

18

150

92

201

233

265

173

13.7

20.2

Bodyweights are mean of 15 animals

Food and water values are the means for three cages of five animals

*P<0.05

**P<0.01

 

Table 2: Results of haematological references

Sex and dose level (mg/kg)

No. of rats examined

Hb (g/100 mL)

PCV (%)

RBC (10⁶/mm³)

Retics (% of RBCs)

Leucocytes

Total (10³/mm³)

Differential (%)

N

E

L

M

Male

Week 2

0

5

11.7

41

4.79

2.4

5.0

10

0

89

1

50

5

11.4

41

4.47

3.0

4.6

6

0

92

2

150

5

11.9

40

4.66

2.8

5.5

8

1

89

2

Female

Week 2

0

5

12.1

39

5.04

2.3

7.0

8

1

89

2

50

5

11.6

40

4.54*

1.8

5.6

10

1

88

1

150

5

12.5

41

5.11

1.8

3.5**

11

1

87

1

Male

Week 6

0

5

14.7

45

6.67

1.1

8.3

11

1

87

1

50

5

14.6

45

6.82

1.0

7.4

18

1

80

1

150

5

14.5

44

6.39

1.1

7.6

13

0

86

1

Female

Week 6

0

5

13.6

42

6.17

0.9

6.9

16

1

82

1

50

5

14.9*

44

6.21

1.0

5.5

13

1

85

1

150

5

14.4

43

6.12

1.0

4.7

12

2

85

1

Male

Week 13

0

14

14.3

45

7.18

1.0

6.1

15

1

82

2

15

14

14.4

44

7.08

1.1

5.5

15

1

83

1

50

15

14.2

45

7.32

1.0

6.3

18

1

80

1

150

15

14.3

45

7.24

1.0

7.4

13

1

84

2

Female

Week 13

0

15

14.0

43

6.13

1.1

3.6

13

2

84

1

15

15

13.8

42

5.98

1.1

4.2

13

1

85

1

50

14

13.9

40

6.17

1.3

4.3

10

1

88

1

150

15

14.0

43

9.12

1.1

4.2

14

1

84

1

Hb- Haemoglobin, PCV - packed cell volume, RBC - red blood cells, Retics - reticulocytes, N - neutrophils, E - eosinophils, L - lymphocytes and M - monocytes

 

Table 3: Mean organ weights

Sex and dose level (mg/kg)

No. of rats examined

Relative organ weights (g/100 g bodyweight)

Terminal bodyweight (g)

Brain

Heart

Liver

Spleen

Kidneys

Stomach

Small intestine

Caecum

Adrenals^a

Gonads^b

Pituitary^a

Thyroid^a

Male

Week 2

0

5

0.94

0.47

3.90

0.43

0.93

0.68

4.13

0.46

26

1.11

5.0

-

177

50

5

0.91

0.44

3.83

0.41

0.88

0.69

4.23

0.45

29

1.20

4.9

-

181

150

5

0.96

0.44

3.87

0.43

0.92

0.67

4.35

0.44

27

1.19

5.1

-

176

Female

Week 2

0

5

1.14

0.53

3.88

0.46

0.94

0.78

4.74

0.56

35

98

7.0

-

143

50

5

1.08

0.44

3.92

0.42

0.90

0.85

4.47

0.49

38

106

7.0

-

153

150

5

1.13

0.64

4.11

0.46

0.94

0.85

4.52

0.57

35

108

6.1

-

147

Male

Week 6

0

5

0.65

0.38

3.01

0.30

0.78

0.54

2.69

0.33

18

1.19

3.1

-

317

50

5

0.66

0.39

2.96

0.33

0.79

0.56

2.94

0.34

20

1.17

3.2

-

291*

150

5

0.69

0.38

3.06

0.30

0.82

0.59

2.81

0.35

19

1.20

3.1

-

278*

Female

Week 6

0

5

0.92

0.43

2.92

0.33

0.78

0.69

2.63

0.38

35

135

6.2

-

190

50

5

0.98

0.44

3.09

0.35

0.81

0.70

3.05

0.40

39

141

6.4

-

187

150

5

0.97

0.45

3.18

0.37

0.80

0.66

3.07

0.40

36

158

5.6

-

187

Male

Week 13

0

15

0.47

0.29

2.58

0.19

0.58

0.46

2.32

0.26

15

0.85

2.5

4.0

411

15

14

0.45

0.28

2.53

0.18

0.58

0.46

2.25

0.24

15

0.88

2.3

4.6

405

50

15

0.45

0.30

2.73

0.19

0.62

0.46

2.24

0.25

16

0.87

2.4

4.6

422

150

15

0.45

0.30

2.78*

0.19

0.63**

0.47

2.31

0.25

15

0.85

2.4

4.4

418

Feale

Week 13

0

15

0.71

0.34

2.48

0.25

0.62

0.56

2.84

0.37

27

56

4.6

6.4

252

15

15

0.71

0.35

2.49

0.26

0.62

0.55

2.81

0.30

27

55

4.1

7.3

255

50

14

0.66

0.34

2.50

0.25

0.62

0.55

2.71

0.27

27

61

4.7

6.2

260

150

15

0.69

0.35

2.51

0.25

0.61

0.54

2.66

0.31

27

59

4.7

6.8

258

^aValues expressed in mg/100 g bodyweight

^bValues for ovaries expressed in mg/100 g bodyweight

Values are means for the no. of rats shown

Statistically significant (Student's t test) * P<0.005 **P< 0.01

Conclusions:

Under the conditions of the test, the test substance 1-phenylethyl acetate induced only minimal effects in male and female rats when dosed up to 150 mg/kg bw/day in corn oil for 13 weeks. In the absence of information to the contrary, the study reports a NOEL of 15 mg/kg bw/day although the authors consider, that the actual NOEL is between 15 and 50 mg/kg bw/day. The NOAEL is considered to be 150 mg/kg bw/day.

Executive summary:

The subchronic toxicity of 1 -phenylethyl acetate was investigated in CFE rats at doses of 0, 15, 50 and 150 mg/kg bw/day (in corn oil). Although not reported as performed in line with a standardised guideline, the methods were comparable to that of OECD 408. Male and female rats were dosed via oral gavage for 13 weeks (with the relevant satellite groups terminated at 2 and 6 weeks), and periodically assessed for signs of toxicity. At the end of the study all remaining animals were sacrificed and assessed for any gross pathological or histopathological changes. Under the conditions of the test, the test substance 1 -phenylethyl acetate induced only minimal effects in male and female rats when dosed up to 150 mg/kg bw/day in corn oil for 13 weeks. In the absence of information to the contrary, the study reports a NOEL of 15 mg/kg bw/day although the authors consider that the actual NOEL is between 15 and 50 mg/kg bw/day. The NOAEL is considered to be 150 mg/kg bw/day.

Reference 2

Endpoint:

sub-chronic toxicity: oral

Type of information:

other: Experimental study for structurally similar analogue included as relevant supporting information.

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

A valid study is available for the analogue substance benzyl acetate. It is conducted in compliance with good scientific principles, with no or minor deviations from standard protocols. The read-across is considered to be suitable based on the structural and “mechanistic action” similarities between the target substance (1-phenylethyl acetate) and source substance (benzyl acetate) and their similar physico-chemical properties.

Reason / purpose for cross-reference:

reference to other study

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity Study in Rodents)

Deviations:

yes

Principles of method if other than guideline:

The methods are comparable to those of OECD Guideline 408. Deviations were present, such as dosing 5 days per week instead of 7 days, with no justification provided and no haematological examinations were performed.

GLP compliance:

not specified

Limit test:

no

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS- Source: Harlan Industries, Indianapolis, IN- Age at study initiation: 6 weeks old- Housing: Polycarbonate, Lab Products Inc., Garfield, NJ, USA- Bedding: Beta-Chips heat treated hardwood chips, Northeastern Products Corp., Warrensburg, NY- Diet (e.g. ad libitum): Wayne Lab-Blox, Allied Mills Inc, Chicago ad libitum- Water (e.g. ad libitum): tap water ad libitum- Acclimation period: observed for 13 days before start of the testENVIRONMENTAL CONDITIONS- Temperature (°C): 21-23 ºC- Humidity (%): 40-60%- Air changes (per hr): 15

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:- Doses were prepared on a weight-to-volume basis by pipetting the appropriate amount of benzyl acetate into a vessel and adding enough corn oil to give the desired concentration. Solutions were mixed until they were visually homogenous. Once prepared, mixtures were stored at 5 °C for no more than 11 days.VEHICLE- Justification for use and choice of vehicle (if other than water): The study opted to dose in corn oil via gavage due to the substance’s volatility and it’s reactivity with moisture.- Amount of vehicle (if gavage): 5 mL/kg

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Samples of benzyl acetate in corn oil were selected at random and analysed periodically at Southern Research Institute.Method used until 04.04.79:Samples of benzyl acetate were received as corn oil mixtures. 0.5 ml aliquots were dissolved in 10 ml chloroform. Analysis was by vapour-phase chromatography under the following conditions:Instrument: Perkin-Elmer 910Detection: Flame ionizationColumn: 3% OV-17 on 80/100 Suplecoport, 1.8 m x 4 mm I.D., glassTemperatures: Inlet, 140 ºC; Oven, 100 ºC, isothermal; Detector, 170 ºCInjection Size: 2 µlRetention time: 2.8 minThere was no correction for workup loss since samples were injected without any extraction or workup procedure. The gavage samples were compared with the reference standards of benzyl acetate prepared volume/volume in corn oil, dissolved in chloroform in the same manner as the gavage samples and analysed under the same chromatographic conditions.Method used after 04.04.79:Samples of benzyl acetate were received as corn oil mixtures in sealed syringe bottles. Samples were extracted with methanol for 3 minutes (20 ml methanol with 0.5ml of sample made up in corn oil). Analysis was by vapour-phase chromatography under the following conditions:Instrument: Sigma 1Detection: Flame ionizationColumn: 3% OV-17 on 80/100 Suplecoport, 1.8 m x 4 mm I.D., glassTemperatures: Inlet, 140 ºC; Oven, 100 ºC, isothermal; Detector, 170 ºCCarrier gas: HeliumInjection Size: 1 µlRetention time: 2.5 minThe gavage samples were compared with the reference standards of benzyl acetate prepared volume/volume in corn oil then extracted with methanol in the same manner as the sample. There was no correction applied to the samples since samples and reference standard were treated in the same manner.

Duration of treatment / exposure:

13 weeks

Frequency of treatment:

5 days per week

Remarks:

Doses / Concentrations:0, 62.5, 125, 250, 500 and 1000 mg/kg bwBasis:

No. of animals per sex per dose:

Ten

Control animals:

no

Details on study design:

- Dose selection rationale: on the basis of results from 14 day study

Observations and examinations performed and frequency:

MORTALITY AND MORBIDITY: Yes- Time schedule: twice daily. Animals judged to be moribund were killed and necropsiedDETAILED CLINICAL OBSERVATIONS: Yes- Time schedule: weekly including palpation for tissue masses or swellingBODY WEIGHT: Yes- Time schedule for examinations: weeklyWATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): NoOPHTHALMOSCOPIC EXAMINATION: NoHAEMATOLOGY: NoCLINICAL CHEMISTRY: NoURINALYSIS: NoNEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: YesOn days 92-96, survivors were killed with carbon dioxide. Necropsies were performed on animals that survived to the end of the study and on all animals found dead (unless precluded in whole or part by autolysis or cannibalization).HISTOPATHOLOGY: YesThe following were examined microscopically for controls, for the highest dose group with at least 60% survivors at the time of group kill and for all animals that died before the survivors of the group were killed; gross lesions, tissue masses, abnormal lymph nodes, skin, mandibular lymph nodes, mammary gland, salivary gland, thigh muscle, bone, bone marrow, thymus, trachea, lungs and bronchi, heart, thyroid, parathyroid, oesophagus, stomach, duodenum, jejunum, ileum, colon, mesenteric lymph nodes, liver, pancreas, spleen, kidneys, adrenals, urinary bladder, seminal vesicles/prostate/testes, ovaries/uterus, nasal cavity, brain, pituitary and spinal cord. Tissues were preserved in 10% neutral buffered formalin, embedded in paraffin, sectioned and stained with hematoxylin and eosin.

Clinical signs:

effects observed, treatment-related

Mortality:

mortality observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

no effects observed

Details on results:

CLINICAL SIGNS AND MORTALITY2/10 males and 1/10 females treated at 1000 mg/kg bw died on day 86. No other animals died. Clinical signs in males and females treated at 1000 mg/kg bw and females treated at 500 mg/kg bw included trembling, ataxia and sluggishness.BODY WEIGHT AND WEIGHT GAINFinal mean body weights of males treated at 1000 mg/kg bw were approximately 12% lower than the control group.GROSS PATHOLOGYThickened stomach walls were observed in 2/9 males and 4/10 females treated at 1000 mg/kg bw. Tissues were re-examined in 1993 as part of an investigation dosing benzyl acetate in feed, performed by the same laboratory. On reexamination, lesions were observed in the brain of male and female 1,000 mg/kg rats (these lesions were less severe than those in the 1993 feed study). The lesions consisted of hippocampal necrosis with a higher incidence and greater severity in males than in females (males 8/8, females 4/10).HISTOPATHOLOGYNo histopathologic effects were observedANALOGUE APPROACH JUSTIFICATION:- See attached “Justification for read-across” document for full details.- In summary, important considerations for the use of read-across for acute toxicity are: i) 1-phenylethyl acetate (the target chemical) has similar physico-chemical properties as benzyl acetate (the source substance), ii) there are structural similarities between the two chemicals, iii) the OECD QSAR Toolbox assigns an identical toxicity profiles to both chemicals, and iv) both chemicals have been tested for acute oral toxicity, which demonstrated that neither substance requires classification for acute toxicity and that the benzyl acetate will represent a worst-case scenario, and are adequate for classification and labelling and risk assessment purposes. The information reported in this summary is included to demonstrate comparability between the source (benzyl acetate) and target (1-phenyl-ethyl acetate) substance.

Dose descriptor:

NOAEL

Effect level:

500 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male

Dose descriptor:

NOAEL

Effect level:

250 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

female

Critical effects observed:

not specified

Table 1: Survival and mean bodyweight of rats administered benzyl acetate by gavage for 13 weeks

		Mean bodyweights (g)
Dose (mg/kg)	Survival	Initial	Final	Change	Final weight relative to controls
Male
0	10/10	119.9 ± 4.5	328.3 ± 11.2	+ 208.4 ± 7.6
62.5	10/10	117.0 ± 3.5	329.7 ± 10.3	+ 212.7 ± 8.5	100.4%
125	10/10	127.1 ± 4.3	334.6 ± 12.0	+ 207.5 ± 9.1	101.9%
250	10/10	124.6 ± 4.4	336.3 ± 7.6	+ 211.7 ± 6.4	102.4%
500	10/10	116.6 ± 4.2	336.8 ± 6.5	+ 200.2 ± 5.1	102.6%
1000	8/10	123.3 ± 4.7	287.6 ± 8.7	+ 164.3 ± 6.2	87.6%
Female
0	10/10	96.7 ± 4.2	180.1 ± 8.2	+ 83.4 ± 5.2
62.5	10/10	95.7 ± 3.2	188.3 ± 6.1	+ 92.6 ± 5.1	104.6%
125	10/10	94.3 ± 1.9	179.9 ± 5.2	+ 85.6 ± 3.7	99.9%
250	10/10	96.0 ± 3.4	183.2 ± 4.4	+ 87.2 ± 3.1	101.7%
500	10/10	103.5 ± 4.4	198.1 ± 6.0	+ 94.6 ± 3.2	110.0%
1000	9/10	84.9 ± 3.0	170.4 ± 5.7	+ 85.5 ± 3.3	94.6%

Conclusions:

Under the conditions of the test, 2/10 males and 1/10 females treated at 1000 mg/kg bw died on day 86 of the study but no other mortality was observed. Final mean body weights of males treated at 1000 mg/kg bw were 12% lower than the control group but no other effects on bodyweights were observed. Clinical signs such as trembling, ataxia and sluggishness were seen in males and females treated at 1000 mg/kg bw and females treated at 500 mg/kg bw. Thickened stomach walls were seen in 2/9 males and 4/40 females treated at 1000 mg/kg bw but no histopathological effects were observed during the course of the study. Tissues were re-examined in 1993 as part of an investigation dosing benzyl acetate in feed, performed by the same laboratory. On reexamination, lesions were observed in the brain of male and female 1,000 mg/kg rats (these lesions were less severe than those in the 1993 feed study). The lesions consisted of hippocampal necrosis with a higher incidence and greater severity in males than in females (males 8/8, females 4/10). The NOAEL has been determined to be 500 mg/kg bw for males and 250 mg/kg bw for females.

Executive summary:

In a non-GLP study, the repeat-dose toxicity of benzyl acetate was investigated in rats. Animals were treated at 0, 62.5, 125, 250, 500 and 1000 mg/kg bw by oral gavage for 13 weeks. Two out of ten males and one out of ten females treated at 1000 mg/kg bw died on day 86 of the study but no other mortality was observed. Final mean body weights of males treated at 1000 mg/kg bw were approximately 12% lower than the control group but no other effects on bodyweights were observed. Clinical signs such as trembling, ataxia and sluggishness were seen in males and females treated at 1000 mg/kg bw and females treated at 500 mg/kg bw. Thickened stomach walls were seen in two out of nine males and four out of ten females treated at 1000 mg/kg bw but no histopathological effects were observed during the course of the study. Tissues were re-examined in 1993 as part of an investigation dosing benzyl acetate in feed, performed by the same laboratory. On reexamination, lesions were observed in the brain of male and female 1,000 mg/kg rats (these lesions were less severe than those in the 1993 feed study). The lesions consisted of hippocampal necrosis with a higher incidence and greater severity in males than in females (males 8/8, females 4/10). The NOAEL has been determined to be 500 mg/kg bw for males and 250 mg/kg bw for females. Based on the results from this study, doses of 250 and 500 mg/kg were selected for both sexes for the two year study.

Reference 3

Endpoint:

sub-chronic toxicity: oral

Type of information:

other: Experimental study for structurally similar analogue included as relevant supporting information.

Adequacy of study:

supporting study

Study period:

30th April 1985 to 2nd August 1985

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

A valid study is available for the analogue substance benzyl acetate. It is conducted in compliance with good scientific principles, with no or minor deviations from standard protocols. The read-across is considered to be suitable based on the structural and “mechanistic action” similarities between the target substance (1-phenylethyl acetate) and source substance (benzyl acetate) and their similar physico-chemical properties.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity Study in Rodents)

GLP compliance:

not specified

Limit test:

no

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS- Source: Frederick Cancer Research Facility (Frederick, MD)- Age at study initiation: average 43 days- Housing: Polycarbonate cages, 5 animals per cage- Diet: NIH-07 open formula meal rat and mouse diet ad libitum- Water: ad libitum- Acclimation period: 13 daysENVIRONMENTAL CONDITIONS- Temperature (°C): 23.6 ± 3 °C- Humidity (%): 46 to 65 %- Air changes (per hr): Minimum of 10 per hour- Photoperiod (hrs dark / hrs light): 12 hours/dayIN-LIFE DATES: From: 30 April 1985 To: 30 July 1985

Route of administration:

oral: feed

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

DIET PREPARATION- Rate of preparation of diet (frequency): Weekly- Mixing appropriate amounts with (Type of food): NIH-07 open formula meal rat and mouse diet (Zeigler Brothers, Inc., Gardners, PA)- Storage temperature of food: -20 °C in the dark

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Homogeneity and stability of the (330 ppm from the mouse study) dose formulations were conducted. 10 g samples of dose formulations were extracted with 50 mL methanol and centrifuged, and 20 mL aliquots of the extracts were mixed with a 2 mL solution of valerophenone (0.66 mg/mL in methanol) and diluted to 25 mL with methanol. The solutions were analysed with gas chromatography with an FID and 10 % SP-2330 on 100/120 Supelcoport and a nitrogen carrier gas at a flow rate of 30 mL/minute with an oven temperature program of 120 °C for 20 minutes, then 120 °C to 200 °C at 10 °C/minute, with a 6-minute hold at 200 °C. Homogeneity was confirmed, stability (with losses of approximately 4 %) was established for at least 3 weeks when the dose formulations were stored in the dark at -20 °C. Dose formulations stored open to air and light showed significant loss (approximately 11 %).Based on the appearance of another peak during the gas chromatographic analysis, the dose formulations were analysed for benzyl alcohol. Benzyl alcohol was identified in the dose formulation by full mass scan gas chromatography/mass spectroscopy. A 10 g sample of the dose formulations was extracted with 50 mL methanol and analysed with a gas chromatographic system similar to that used in the homogeneity study but with a helium carrier gas and an oven temperature program of 40 °C for 3 minutes, then 40 °C to 225 °C at 10 °C/minute. For quantification of benzyl alcohol, dose formulations were extracted with methanol, 0.06 mg/mL valerophenone in methanol was added and the extracts were diluted further with methanol prior to gas chromatographic analysis. The system was the same as that used for the homogeneity studies, but the oven temperature was 110 °C. These analyses indicated concentrations of benzyl alcohol ranging from 0.9 % to 2.0 % relative to benzyl acetate concentrations after 3 days storage under simulated animal cage conditions.Dose formulations of benzyl acetate were analysed by the study laboratory using gas chromatography with the system described for the homogeneity study but with an oven temperature program of 125 °C for 5 minutes, then 125 °C to 140 °C at 5 °C/minute, with a 10-minute hold at 140 °C. Dose formulations were analysed four times during the study. All dose formulations were equal to or within 10 % of the target concentrations.

Duration of treatment / exposure:

Food was available ad libitum for 13 weeks

Frequency of treatment:

Daily

Remarks:

Doses / Concentrations:0, 3130, 6250, 12,500, 25,000 and 50,000 ppmBasis:other: analytical concentration

Remarks:

Doses / Concentrations:0, 230, 460, 900, 1750 or 4390 mg/kg bw/day (males) and 0, 240, 480, 930, 1870 or 4500 mg/kg bw/day (females)Basis:actual ingested

No. of animals per sex per dose:

10

Control animals:

yes, plain diet

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes- Time schedule: Twice dailyDETAILED CLINICAL OBSERVATIONS: Yes- Time schedule: Weekly.BODY WEIGHT: Yes- Time schedule for examinations: Bodyweights were recorded initially, then weekly and at the end of the studyFOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: YesThe average feed consumption during weeks 2 through 13 was expressed as grams per animal per day. Feed consumption was not calculated for week 1.HAEMATOLOGY: Yes, blood was collected from the orbital sinus.- Parameters checked: haematocrit, haemoglobin, erythrocytes, mean erythrocyte volume, mean erythrocyte haemoglobin, mean erythrocyte haemoglobin concentration, platelets, reticulocytes, and leukocyte count and differential.CLINICAL CHEMISTRY: Yes, blood was collected for analysis from the orbital sinus. - Parameters: Cholesterol and triglyceride were analysed from the blood samples. ENZYME ASSAYS:Pancreas samples from all controls and exposed rats, except the 50,000 ppm exposure group, were collected. Liver samples from controls, 25,000 and 50,000 ppm females were also collected. Enzymes: amylase, lipase, carboxypeptidase, chymotrypsin and ribonuclease were analysed from the pancreatic samples. Liver peroxisomes were analysed by electron microscopy.

Sacrifice and pathology:

GROSS PATHOLOGY: Yes, animals were examined grossly at necropsyHISTOPATHOLOGY: Yes. Histopathologic examinations were performed on all control, 25,000 and 50,000 ppm animals. In addition to gross lesions, tissue masses, and associated lymph nodes, the following tissues were examined: adrenal gland, bone (including marrow), brain, oesophagus, heart, kidney, large intestine (cecum, colon and rectum), liver, lung, mammary gland, nose, ovary, pancreas, parathyroid gland, pituitary gland, preputial or clitoral gland, prostate gland, salivary gland, skin, small intestine, spleen, stomach (forestomach and glandular), testis with epididymis and seminal vesicle, thigh muscle, thymus, thyroid gland, tongue, trachea, urinary bladder and uterus. The testis with epididymis of 6250 and 12,500 ppm male rats were also examined.

Statistics:

Differences in mean bodyweights compared to the control group were assessed using Williams' or Dunnett's test (P=<0.05). Histopathological lesions such as the hepatic peroxisomes were assessed by mophometric analysis, statistical significance was measured using Student's t-test (P=<0.001). Incidences of nonneoplastic lesions compared to the control group were assessed using Fisher's exact test (P=<0.01).

Clinical signs:

effects observed, treatment-related

Mortality:

mortality observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

effects observed, treatment-related

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

no effects observed

Details on results:

CLINICAL SIGNS AND MORTALITYNine males and nine females receiving 50,000 ppm test substance died or were killed moribund between weeks 2 and 8 of the study. One 12,500 ppm female died under anaesthesia during blood collection at the end of the study. Clinical findings related to toxicity observed in the 50,000 ppm animals included tremors, ataxia and urine stains. These findings were first observed on day 15 of the study in nine males and six females and continued until the end of the study.BODY WEIGHT AND WEIGHT GAINThe mean bodyweight and bodyweight gain of 25,000 ppm males were significantly lower than those of the control. The final mean bodyweight of 25,000 ppm males was 10% lower than that of the control group, whereas the final bodyweights of the surviving 50,000 ppm males and females were less than half those of the controls. Final mean bodyweights of males and females of other exposed groups were similar to or slightly lower than those of the controls.FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study)Feed consumption was comparable with the control in all groups except 25,000 and 50,000 ppm males and 50,000 ppm females. The reduced feed consumption by 25,000 and 50,000 ppm males and 50,000 ppm females may have been due to decreased palatability and/or toxicity.HAEMATOLOGYExcluding the data from the 50,000 ppm males and females (only one survivor in each group), haematology values for all exposed groups were similar to those of the control groups.CLINICAL CHEMISTRYThe clinical chemistry evaluations showed significantly lower cholesterol levels in 12,500 and 25,000 ppm females than in the controls. No chemical-related differences occurred in the cholesterol or triglyceride levels in exposed males.ENZYME ASSAYSNo chemical-related differences in the activity of pancreatic enzymes in the homogenate of pancreata were found. No evaluations of the highest exposure group were made due to reduced survival. The amylase and carboxypeptidase A activities increased with exposure level and chymotrypsin activity decreased with exposure level in males. Since these enzymes are produced by pancreatic acinar cells, and since no chemical-related increase in the incidence of pancreatic acinar cell hyperplasia was observed, the differences in activities observed in these enzymes were not considered to be related to test substance administration.ORGAN WEIGHTSSlight differences in organ weights were observed and were considered secondary to the reduced bodyweights.HISTOPATHOLOGY: NON-NEOPLASTICIn the evaluation of hepatic peroxisomes in females, significant increases in volume, surface, and numerical densities of peroxisomes in liver occurred in the 25,000 ppm group. Compared to control values, 25,000 ppm females had a 1.6-fold increase in peroxisomal volume, a 2.0-fold increase in surface density, and a 2.9-fold increase in numerical density.In exposed females, peroxisomes were identified by the cytochemical localisation of catalase activity. The hepatocytes of 25,000 ppm females had typical morphology; however, the number, size, and shape of the peroxisomes varied considerably. In the livers of two female rats receiving 25,000 ppm, numerous bizarrely shaped degenerating peroxisomes occurred.The diffusion of electron-dense reactions products was visible through the peroxisomal membrane. The peroxisomes apparently degenerated through autophagic vacuoles. A higher magnification examination of hepatocytes in exposed females showed a close spatial relationship between a smooth endoplasmic reticulum and peroxisomes. The limiting membrane of the peroxisomes appeared to be intact, although in some of the peroxisomes, diffusion of catalase was visible. Membrane continuity between peroxisome and microperoxisome was also observed. Peroxisomes in the proximity of lipid droplets and mitochondria were apparent.The principal non-neoplastic lesions occurred in the brain, kidney, tongue and skeletal muscles of the thigh. Necrosis of the brain involving the cerebellum and/or hippocampus occurred in all 50,000 ppm males and females but did not occur in any of the 25,000 ppm animals. The lesions were consistent in location, primarily involved the granular layer of the cerebellum and the pyramidal layer of the hippocampus, and were characterised by degeneration and extensive necrosis of neurons and glial cells. The necrosis was moderate or marked in severity in all 50,000 ppm males and in most females and mild in a few females. The severity of the lesion increased with length of exposure to the test substance. The Purkinje cells of one female were markedly vacuolated. Concretions suggestive of mineral deposits were associated with cerebellar necrosis in three males and one female of the 50,000 ppm groups. The concretions appeared as localised or focal aggregates of roughly spherical basophilic structures. This lesion was mild to marked in severity and occurred in those animals with the longest exposure to the test substance.Renal tubule degeneration and regeneration occurred in seven males and eight females in the 50,000 ppm groups. The changes occurred primarily in the outer cortex of the kidney, with the severity ranging from minimal to moderate. Renal tubule degeneration was characterised by slightly basophilic cells with vacuolated cytoplasm lining the renal tubules, which in some instances had dilated lumina. Karyorrhectic nucleu occasionally occurred in renal tubule epithelial cells, denoting minimal necrosis. Renal tube regeneration was characterised by increased numbers of mitotic figures. These degenerative and regenerative renal lesions did not occur in 25,000 ppm rats. Nephropathy, a spontaneous kidney change primarily occurring in male rats, occurred in nine control male rats and in four 25,000 ppm males and was minimal in severity. Nephropathy did not occur in any 50,000 ppm males and may have been masked by the chemical-related renal tubule degeneration and regeneration.Degeneration and sarcolemma nuclear hyperplasia occurred in the skeletal muscles of the thigh and in the tongue of most 50,000 ppm males and female. Degeneration was characterised by randomly arranged muscle fibers with increased basophilia, loss of cross-striations, and faint vacuolation. The severity of the lesion varied from mild to marked, and in some of the more severe cases, the degenerated muscle fibres had increased eosinophilia and marked dissolution with the infiltration of mixed inflammatory cells. Accompanying the degenerative changes were increased numbers (proliferation) of the sacrolemmal nuclei of mild to marked severity. In one 50,000 ppm female, diffuse infiltration of mast cells and neutrophils into the tongue musculature occurred. Mild chronic inflammation of the tongue in one male and one 25,000 ppm female was focal in nature and probably spontaneous. No chemical-related skeletal muscle or tongue lesions occurred in the 25,000 ppm groups.Testicular changes related to chemical exposure occurred in males receiving 12,500, 25,000 and 50,000 ppm dosed feed. The lesions were characterised by mild or moderate aspermatogenesis in two 50,000 ppm animals and atrophy of seminiferous tubules in two 25,000 ppm and one 12,500 ppm animal. In one 25,000 ppm animal, the seminiferous tubule atrophy was marked in severity and included atypical cells (enlarged, degenerated spermatozoa) in the corresponding epididymis and mild interstitial cell hyperplasia. The seminiferous tubule atrophy was minimal in severity in one 12,500 ppm animal. No testicular lesions occurred in the 6,250 ppm or lower exposure levels.Several changes in 50,000 ppm animals were considered indirectly related to chemical exposure. These changes included depletion of the cellular components of the bone marrow, thymus (atrophy), and splenic lymphoid follicles, zymogen granule depletion and increased basophilia of the pancreated acinar cells (cytoplasmic alteration), minimal to mild erosions of the glandular stomach, secretory depletion of the seminal vesicles and immature/hypoplastic uterus. These changes are frequently observed in rodents and are usually caused by debilitation, stress, age or poor nutrition. Although ultrastructural changes of liver peroxisomes occurred in 25,000 ppm females, no chemical-related lesions were found in the liver of either sex using light microscopy.ANALOGUE APPROACH JUSTIFICATION:- See attached “Justification for read-across” document for full details.- In summary, important considerations for the use of read-across for acute toxicity are: i) 1-phenylethyl acetate (the target chemical) has similar physico-chemical properties as benzyl acetate (the source substance), ii) there are structural similarities between the two chemicals, iii) the OECD QSAR Toolbox assigns an identical toxicity profiles to both chemicals, and iv) both chemicals have been tested for acute oral toxicity, which demonstrated that neither substance requires classification for acute toxicity and that the benzyl acetate will represent a worst-case scenario, and are adequate for classification and labelling and risk assessment purposes. The information reported in this summary is included to demonstrate comparability between the source (benzyl acetate) and target (1-phenyl-ethyl acetate) substance.

Dose descriptor:

NOAEL

Effect level:

12 500 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: see 'Remark'

Dose descriptor:

NOEL

Effect level:

6 250 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Equivalent to 460 mg/kg bw/day for male rats and 480 mg/kg bw/day for female rats.

Critical effects observed:

not specified

Table 1: Survival, Mean Bodyweights, and Feed consumption

Dose (ppm)	Survival	Mean bodyweights (g)			Final weight relative to controls (%)	Feed consumption^a
		Initial	Final	Change
Male
0	10/10	131 ± 2	349 ± 5	219 ± 4		17.8
3130	10/10	131 ± 2	352 ± 5	222 ± 6	101	17.8
6250	10/10	127 ± 3	348 ± 8	221 ± 9	100	17.7
12500	10/10	130 ± 3	342 ± 6	212 ± 7	98	17.1
25000	10/10	129 ± 2	315 ± 8**	186 ± 6**	90	15.8
50000	1/10^b	127 ±3	128	-	36	10.2
Female
0	10/10	104 ± 2	199 ± 2	95 ± 2		11.8
3130	10/10	105 ± 2	196 ± 3	91 ± 2	98	11.6
6250	10/10	104 ± 2	194 ± 4	90 ± 3	97	11.5
12500	9/10^c	106 ± 2	191 ± 3	85 ± 3*	96	11.1
25000	10/10	105 ± 2	189 ± 5	84 ± 4**	95	11.0
50000	1/10^d	102 ± 2	93	-	47	9.0

 ^agrams per animal per day based on weeks 2 to 13

^bweek of death: 2, 3, 4, 4, 4, 5, 6, 7, 8

^cweek of death: 13

dweek of death: 2, 2, 3, 3, 3, 4, 4, 4, 5

* significantly different from control (p ≤ 0.05)

** p ≤ 0.01

Table 2: Mophometric Analysis of Hepatic Peroxisomes for Females^a

Dose (ppm)	0	25000	50000
n	10	10	1
Volume density (% cytoplasm)	1.04 ± 0.05	1.65 ± 0.12*	3.100
Surface density (µm^2/µm^3)	0.114 ± 0.004	0.231 ± 0.011*	0.300
Numerical density (µm^-3)	0.140 ± 0.013	0.404 ± 0.040	0.341

 ^amean ± standard deviation

*significantly different (p ≤ 0.001) from the control group

Table 3: Selected Incidences of Nonneoplastic Lesions

Dose (ppm)		0	25000	50000
Male
Brain (Cerebellum/Hippocampus)		10	10	9
	Necrosis	0	0	9*(3.5)
	Concretions	0	0	3 (3.0)
Kidney		10	10	9
	Renal Tubule Degeneration	0	0	7*(2.1)
	Renal Tubule Regeneration	0	0	6*(2.3)
Skeletal Muscle		10	10	9
	Degeneration	0	0	8*(2.2)
	Sacrolemma Nuclear Hyperplasia	0	0	9*(3.1)
Tongue		10	10	9
	Degeneration	0	0	7*(2.3)
	Sacolemma Nuclear Hyperplasia	0	0	9*(2.4)
Female
Brain (Cerebellum/Hippocampus)		10	10	10
	Necrosis	0	0	10*(2.9)
	Concretions	0	0	1 (4.0)
Kidney		10	10	10
	Renal Tubule Degeneration	0	0	8*(1.7)
	Renal Tubule Regeneration	0	0	8*(2.0)
Skeletal Muscle		10	10	10
	Degeneration	0	0	8*(2.6)
	Sacrolemma Nuclear Hyperplasia	0	0	8*(2.7)
Tongue		10	10	10
	Degeneration	0	0	6*(2.2)
	Sacolemma Nuclear Hyperplasia	0	0	9*(2.3)

*significantly difference (p≤0.01) from control group by Fisher's exact test

Conclusions:

Nine males and nine females receiving 50,000 ppm test substance died or were killed moribund between weeks 2 and 8 of the study. The mean bodyweight gain and the final mean bodyweight of the 25,000 ppm males were significantly lower (P=<0.01) than those of the control group. Feed consumption by exposed rats, except the 25,000 and 50,000 ppm males and 50,000 ppm females, was similar to that by the controls. The reduced feed consumption by 25,000 and 50,000 ppm males and 50,000 ppm females may have been due to toxicity or decreased palatability. Tremors and ataxia occurred only in the 50,000 ppm animals. These findings were observed on day 15 in nine males and six females and continued until the end of the study. Cholesterol levels in 12,500 and 25,000 ppm females and triglyceride levels in 25,000 ppm females were lower than those in the controls. Chemical related lesions occurred in the brain, kidney, tongue and skeletal muscles of the thigh. Necrosis of the brain involving the cerebellum and/or hippocampus, degeneration and regeneration of the renal tubule epithelium and degeneration of the sacrolemma nuclear hyperplasia of the tongue and skeletal muscles occurred in most male and female 50,000 ppm animals.

Executive summary:

In a GLP study performed to a method similar to OECD Guideline 408, groups of 10 male and 10 female F344/N rats were fed diets containing 0, 3130, 6250, 12,500, 25,000 or 50,000 ppm (0, 230, 460, 900, 1750 or 3900 mg/kg bw for males and 0, 240, 480, 930, 1870 or 4500 mg/kg for females) benzyl acetate for 13 weeks.

Nine males and nine females receiving 50,000 ppm benzyl acetate died or were killed moribund between weeks 2 and 8 of the study. The mean bodyweight gain and the final mean bodyweight of the 25,000 ppm males were significantly lower (p≤0.01) than those of the control group. Feed consumption by exposed rats, except the 25,000 and 50,000 ppm males and 50,000 ppm females, was similar to that by the controls. The reduced feed consumption by 25,000 and 50,000 ppm males and 50,000 ppm females may have been due to toxicity or decreased palatability. Tremors and ataxia occurred only in the 50,000 ppm rats. These findings were observed on day 15 in nine males and six females and continued until the end of the study. Cholesterol levels in 12,500 and 25,000 ppm females and triglyceride levels in 25,000 ppm females were lower than those in the controls.

Chemical related lesions occurred in the brain, kidney, tongue and skeletal muscles of the thigh. Necrosis of the brain involving the cerebellum and/or hippocampus, degeneration and regeneration of the renal tubule epithelium and degeneration of the sacrlemma nuclear hyperplasia of the tongue and skeletal muscles occurred in most male and female 50,000 ppm rats.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

150 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

The key study is performed in line with sound scientific principles in line with a method comparable to an appropriate standardised guideline and is of sufficient quality with a Klimisch score of 2. Sufficient supporting studies are also available.

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

The NOAEL for the 90-Day Repeated Dose Toxicity study on Gardenol dosed via the oral route was 150 mg/kg bw/day.

The NOAEL for the supporting structurally similar analogue benzyl acetate was 250 mg/kg bw/day for females and 500 mg/kg bw/day for males according to a study performed in line with methodology considered to be equivalent or similar to OECD Guideline 408.

 

Repeated Dose Toxicity studies: Dermal and Inhalation: Data waivers have been submitted to address repeat dose toxicity via the dermal and inhalatory routes. Exposure via the oral route is considered to be the most likely route of exposure and sufficient repeat dose oral toxicity studies have been submitted.

Justification for classification or non-classification

The key study submitted to evaluate the repeated dose toxicity of the test substance via the oral route (considered the most relevant route) indicated that the test substance does not require classification for repeated dose toxicity in accordance with Directive 67/548/EEC and Regulation 1272/2008. This is further supported by the data on the structurally closely related analogue benzyl acetate provided as supporting information.