2-phenoxyethanol

Repeated dose toxicity: oral

Administrative data

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

No English test report is available (study in Japanese), but an English summary and all tables and figures in English are available.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-phenoxyethanol

EC Number:

204-589-7

EC Name:

2-phenoxyethanol

Cas Number:

122-99-6

Molecular formula:

C8H10O2

IUPAC Name:

2-phenoxyethan-1-ol

Specific details on test material used for the study:

- Name of test material (as cited in study report): 2-Phenoxyethanol
- Analytical purity: 99.9%
- Lot/batch No.: WAL415

Test animals

Species:

rat

Strain:

Fischer 344/DuCrj

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: the average weight of males was 126 g and 99 g of the females

Administration / exposure

Route of administration:

oral: drinking water

Vehicle:

unchanged (no vehicle)

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Stability was confirmed using quantitative HPLC analysis

Duration of treatment / exposure:

13 weeks

Frequency of treatment:

Daily, the test substance was administered to the drinking water.

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

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

Remarks:

male

Doses / concentrations 2

Dose / conc.:

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

Remarks:

male

Doses / concentrations 3

Dose / conc.:

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

Remarks:

male

Doses / concentrations 4

Dose / conc.:

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

Remarks:

male

Doses / concentrations 5

Dose / conc.:

1 514 mg/kg bw/day (actual dose received)

Remarks:

male

Doses / concentrations 6

Dose / conc.:

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

Remarks:

female

Doses / concentrations 7

Dose / conc.:

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

Remarks:

female

Doses / concentrations 8

Dose / conc.:

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

Remarks:

female

Doses / concentrations 9

Dose / conc.:

1 000 mg/kg bw/day (actual dose received)

Remarks:

female

Doses / concentrations 10

Dose / conc.:

1 702 mg/kg bw/day (actual dose received)

Remarks:

female

Doses / concentrations 11

Dose / conc.:

1 250 mg/L drinking water

Doses / concentrations 12

Dose / conc.:

2 500 mg/L drinking water

Doses / concentrations 13

Dose / conc.:

5 000 mg/L drinking water

Doses / concentrations 14

Dose / conc.:

10 000 mg/L drinking water

Doses / concentrations 15

Dose / conc.:

20 000 mg/L drinking water

No. of animals per sex per dose:

10

Control animals:

yes, concurrent no treatment

Examinations

Observations and examinations performed and frequency:

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: weekly

BODY WEIGHT: Yes
- Time schedule for examinations: weekly

FOOD CONSUMPTION, WATER CONSUMPTION AND BODY WEIGHT:
- Time schedule: weekly

HAEMATOLOGY:
- Time schedule for collection of blood: The surviving animals were bled at the end of the study.
- Anaesthetic used for blood collection: No data
- Animals fasted: No data
- How many animals: Haematology was examined in every male rat from all dose groups. Haematology in female rats was examined in all rats from all dose groups with the exception from 1 rat in the control group.
- Parameters: Red blood cell count, haemoglobin, haematocrit, mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration, platelet count, reticulocytes, prothrombin time, activated partial thromboplastin, white blood cell count, and differential white blood cell count.

CLINICAL CHEMISTRY:
- Time schedule for collection of blood: The surviving animals were bled at the end of the study.
- Animals fasted: No data
- How many animals: All animals
- Parameters: Plasma chemistry analyses included total protein, albumin, A/G ratio, total bilirubin, glucose, total cholesterol, triglyceride, phospholipid, aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), γ-glutamyl transpeptidase, creatine phosphokinase, urea nitrogen, creatinine, sodium, potassium, chloride, calcium, and inorganic phosphorus.

URINALYSIS:
- Time schedule for collection of urine: Urine samples were collected for urinalyses at the end of treatment.
- Metabolism cages used for collection of urine: No data
- Animals fasted: No data
- Parameters: pH, protein, glucose, ketone body, bilirubin, occult blood, and urobilinogen

Sacrifice and pathology:

GROSS PATHOLOGY AND HISTOPATHOLOGY: Yes, gross pathology at necropsy, organ weights (thymus, adrenal, testes, ovary, heart, lung, kidney, spleen, liver, brain, and thyroid) and histopathology were conducted.

Statistics:

Incidences of non-neoplastic lesions and urinalysis were analyzed by Chi-square test. Changes in body weight, water consumption, food consumption, hematological and blood biochemical parameters, and organ weights were analyzed by Dunnett’s test.

Results and discussion

Results of examinations

Description (incidence and severity):

Soiled fur around genitalia was observed in all animals administered with 20,000 mg/L test substance and in a few animals exposed to 5000 and 10,000 mg/L.

Description (incidence):

One male rat in the 20000 mg/L dose group did not survive the 13th study week, all other animals survived until necropsy.

Description (incidence and severity):

After 13 weeks a significant decrease in body weight was observed in both sexes of the 20,000 mg/L dose group (±19% lower compared to the control group). Decrease in body weight was also observed in females administered with 10,000 mg/L test substance (±8% lower compared to the control group)

Description (incidence and severity):

During the entire study a decrease in food consumption was observed in males and females in the 20,000 mg/L dose groups (±20% relative to controls) and in females in the 10,000 mg/L dose group (±10% relative to controls).

Description (incidence and severity):

During the entire study water consumption was decreased in females administered with 20,000 mg/L. The decrease in females was approximately 30-40%. In males dosed with 5000, 10000, and 20000 mg/L decreased water consumption was observed untill the 9th week of the study.

Description (incidence and severity):

Red blood cell count and platelet count were reduced in the 10000 and 20000 mg/L dose groups of both sexes. In males platelet count was also reduced in animals exposed to 5000 mg/L. The reduction of platelets in the 5000 mg/L dose group was less then 10% compared to controls and no changes were observed in coagulation parameters. Therefore no evidence of a functional effect was present. In the 10000 and 20000 mg/L dose groups in females and in the 20000 mg/L dose group in males haemoglobin was reduced. MCV and MCH were increased in males (10000 and 20000 mg/L) and females (20000 mg/L). In females administered with 20000 mg/L an increased reticulocyte count was measured.

Description (incidence and severity):

In males exposed to 20000 mg/L test substance a reduction in total protein, glucose, sodium, calcium and an increase in A/G ratio, total cholesterol, phospholipids, urea nitrogen, potassium was observed. In the 10000 mg/L dose group only the effects on total protein, cholesterol, phospholipids, sodium and potassium were present. No effects were observed at lower dose levels. In female exposed to 20000 mg/L increases in A/G ratio, ALP, and urea nitrogen was observed. In the 10000 mg/L dose group total protein was decreased and urea nitrogen was increased.

Description (incidence and severity):

Statisticaly significant decrease in pH was observed after administration of 20000 mg/L in both sexes. This could be the result of excretion of 2-phenoxyacetic acid, the major metabolite of the test substance.

Description (incidence and severity):

In the 10000 mg/L dose groups, the relative liver weight was increased in males and females. In addition in females absolute adrenal weight was decreased and relative kidney and brain weights were increased. In males of the 20000 mg/L dose group a decrease in absolute thymus, testes, heart, lung, and spleen was observed. In addition an increase in relative testes, lung, kidney, liver, brain, and thyroid was determined. In females of the 20000 mg/L dose group decreases in absolute thymus, adrenals, ovaries, heart, lungs, and spleen weights were determined. Relative kidney, liver, and brain weights were increased.

Description (incidence and severity):

In 2 males and 1 female dosed with 10000 mg/L, slight urothelial hyperplasia of the renal pelvis was observed. Slight to moderate urothelial hyperplasia was observed in 6 males of the highest dose group. In 2 and 7 females dosed with 10000 and 20000 mg/L test substance, respectively slight to moderate urinary bladder transitional epithelial hyperplasia was observed. Slight urinary bladder transitional epithelial hyperplasia was also observed in one male of the high dose group.

Details on results:

CLINICAL SIGNS AND MORTALITY
Soiled fur around genitalia was observed in all animals administered with 20,000 mg/L test substance and in a few animals exposed to 5000 and 10,000 mg/L. One male rat in the 20000 mg/L dose group did not survive the 13th study week, all other animals survived until necropsy.

BODY WEIGHT AND WEIGHT GAIN
After 13 weeks a significant decrease in body weight was observed in both sexes of the 20,000 mg/L dose group (±19% lower compared to the control group). Decrease in body weight was also observed in females administered with 10,000 mg/L test substance (±8% lower compared to the control group)

FOOD CONSUMPTION AND WATER CONSUMPTION
During the entire study a decrease in food consumption was observed in males and females in the 20,000 mg/L dose groups (±20% relative to controls) and in females in the 10,000 mg/L dose group (±10% relative to controls). During the entire study water consumption was decreased in females administered with 20,000 mg/L. The decrease in females was approximately 30-40%. In males dosed with 5000, 10000, and 20000 mg/L decreased water consumption was observed untill the 9th week of the study.

HAEMATOLOGY
Red blood cell count and platelet count were reduced in the 10000 and 20000 mg/L dose groups of both sexes. In males platelet count was also reduced in animals exposed to 5000 mg/L. The reduction of platelets in the 5000 mg/L dose group was less then 10% compared to controls and no changes were observed in coagulation parameters. Therefore no evidence of a functional effect was present. In the 10000 and 20000 mg/L dose groups in females and in the 20000 mg/L dose group in males haemoglobin was reduced. MCV and MCH were increased in males (10000 and 20000 mg/L) and females (20000 mg/L). In females administered with 20000 mg/L an increased reticulocyte count was measured.

CLINICAL CHEMISTRY
In males exposed to 20000 mg/L test substance a reduction in total protein, glucose, sodium, calcium and an increase in A/G ratio, total cholesterol, phospholipids, urea nitrogen, potassium was observed. In the 10000 mg/L dose group only the effects on total protein, cholesterol, phospholipids, sodium and potassium were present. No effects were observed at lower dose levels. In female exposed to 20000 mg/L increases in A/G ratio, ALP, and urea nitrogen was observed. In the 10000 mg/L dose group total protein was decreased and urea nitrogen was increased.

URINALYSIS
Statisticaly significant decrease in pH was observed after administration of 20000 mg/L in both sexes. This could be the result of excretion of 2-phenoxyacetic acid, the major metabolite of the test substance.

ORGAN WEIGHTS
In the 10000 mg/L dose groups, the relative liver weight was increased in males and females. In addition in females absolute adrenal weight was decreased and relative kidney and brain weights were increased. In males of the 20000 mg/L dose group a decrease in absolute thymus, testes, heart, lung, and spleen was observed. In addition an increase in relative testes, lung, kidney, liver, brain, and thyroid was determined. In females of the 20000 mg/L dose group decreases in absolute thymus, adrenals, ovaries, heart, lungs, and spleen weights were determined. Relative kidney, liver, and brain weights were increased.

HISTOPATHOLOGY
In 2 males and 1 female dosed with 10000 mg/L, slight urothelial hyperplasia of the renal pelvis was observed. Slight to moderate urothelial hyperplasia was observed in 6 males of the highest dose group. In 2 and 7 females dosed with 10000 and 20000 mg/L test substance, respectively slight to moderate urinary bladder transitional epithelial hyperplasia was observed. Slight urinary bladder transitional epithelial hyperplasia was also observed in one male of the high dose group.

ANALYTICAL DATA DRINKING WATER:
Analytical data verified that the test material content in drinking water was within acceptable limits of the target concentrations (101-102%).

Effect levels

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

haematology

histopathology: non-neoplastic

Target system / organ toxicity

Critical effects observed:

not specified