Sodium (3-hydroxy-2-pentylcyclopentyl)acetate

Repeated dose toxicity: dermal

Administrative data

Endpoint:

short-term repeated dose toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2008-10-21 to 2009-10-01

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study according to GLP guideline 410

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 410 (Repeated Dose Dermal Toxicity: 21/28-Day Study)

Deviations:

yes

Remarks:

Application period amended

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Mexoryl SBO

IUPAC Name:

Mexoryl SBO

Test material form:

other: colorless to yellowish liquid

Details on test material:

- Name of test material (as cited in study report): Mexoryl SBO

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Janvier, Le Genest-Saint-Isle, France
- Age at study initiation: approximately 9 weeks old
- Weight at study initiation: 384 - 444 g males, 231 -261 g females
- Fasting period before study: no
- Housing: in individual suspended wire-mesh cages
- Diet (e.g. ad libitum): All animals had free access to SsniffR/M-H pelleted maintenance diet, batch Nos. 1860828 and 7691203 (SSNIFF Spezialdiäten GmbH, Soest, Germany), which was distributed weekly. During periods of fasting food was removed but the animals were not deprived of water.
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±2
- Humidity (%): 50±20
- Air changes (per hr): 12 cycles
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

water

Details on exposure:

TEST SITE
- Area of exposure: from 45 to 50 cm^2 in males and from 30 to 35 cm^2 in females
- % coverage: 10
- Type of wrap if used: a film
- Time intervals for clipplings: at least 4 hours before dosing and at least once a week

REMOVAL OF TEST SUBSTANCE
- Washing (if done): with tap water and dried with cotton wool
- Time after start of exposure: 6 hours

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.236, 0.472 and 0.943 mL/kg/day
- Concentration (if solution): 0, 250, 500 and 1000 mg/kg/day
- Constant volume or concentration used: no

USE OF RESTRAINERS FOR PREVENTING INGESTION: yes

Analytical verification of doses or concentrations:

no

Duration of treatment / exposure:

2 weeks

Frequency of treatment:

daily

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 250, 500, 1000 mg/kg/day
Basis:
nominal per unit body weight

No. of animals per sex per dose:

5

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: The dose-levels were specified by the Sponsor based on the results of a previous study (CIT/Study No. 26883 TSR) in which the test item, was administered daily by the oral route (gavage) at dose-levels of 100, 300 or 1000 mg/kg/day, or by the cutaneous route at 100 mg/kg/day for 4 weeks. In this previous study, the No Observed Adverse Effect Level (NOAEL) for the oral route was considered to be 300 mg/kg/day, and the No Observed Effect Level (NOEL) for the cutaneous route was considered to be higher than 100 mg/kg/day. When the test item was applied by the cutaneous route at 100 mg/kg/day, no overt toxic effects were observed. Scabs, associated with very slight or well-defined erythema, were transiently observed in some animals. Since these signs were observed transiently and with a similar incidence in control and treated animals, they were considered to be related to treatment with the vehicle rather than treatment with the test item.

- Rationale for animal assignment (if not random): during the acclimation periods, the required number of animals (20 males and 20 females for phase I and 10 males and 10 females for phase II) were selected according to body weight and clinical condition. They were then allocated to groups (by sex) according to a
computerized stratification procedure, so that the average body weight of each group was similar.

- Section schedule rationale (if not random): no data

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice a day

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: once a day

DERMAL IRRITATION (if dermal study): Yes
- Time schedule for examinations: before each daily treatment (including before dosing on day 1)

BODY WEIGHT: Yes
- Time schedule for examinations: once before group allocation, on the fist day of treatmentand on days 4, 8, 11 and 14.

FOOD CONSUMPTION:
- Food consumption for each animal determined and mean daily diet consumption calculated as mg food/kg body weight/day: Yes

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: No data

WATER CONSUMPTION: No data

OPHTHALMOSCOPIC EXAMINATION: No data

HAEMATOLOGY: Yes
- Time schedule for collection of blood: day 15
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: Yes
- How many animals: all
- Following parameters were examined: Erythrocytes (RBC), Hemoglobin (HB), Mean cell volume (MCV), Packed cell volume (PCV), Mean cell hemoglobin concentration (MCHC), Men cell hemoglobin (MCH), Thrombocytes (PLT), Leucocytes (WBC), Differential white cell count with cell morphology: neutrophils (N), eosinophils (E), basophils (B), lymphocytes and large unstained cells (L+LUC), monocytes (M); Reticulocytes (RTC), Prothrombin time (PT), Activated partial thromboplastin time (APTT), Fibrinogen (FIB).

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: day 15
- Animals fasted: Yes
- How many animals: all
- Following parameters were examined: Sodium (Na+), Potassium (K+), Chloride (Cl-), Calcium (Ca++), Inorganic phosphorus (I. PHOS), Glucose (GLUC), Urea (UREA), Creatinine (CREAT), Total bilirubin (TOT.BIL.), Total proteins (PROT), Albumin (ALB),Albumin/globulin ratio (A/G), Total cholesterol (CHOL), Triglycerides (TRIG), Alkaline phosphatase (ALP), Aspartate aminotransferase (ASAT), Alanine aminotransferase (ALAT).

URINALYSIS: Yes
- Time schedule for collection of urine: week 3 (end of the treatment period)
- Metabolism cages used for collection of urine: Yes
- Animals fasted: Yes
- Following parameters were examined: volume (Volume), pH (pH), Specific gravity (SP.GRAV), Proteins (PROT), Glucose (GLUC), Ketones (CETO), Bilirubin (BILI), Nitrites (NITR), Blood (haemoglobin) (BLOOD), Urobilinogen (UROB), Cytology of sediment: leucocytes (WBC), erythrocytes (RBC), cylinders (CYLIN), magnesium ammonium phosphate crystals (AMM.PH), calcium phosphate crystals (CAL.PH), calcium oxalate crystals (CAL.OX.), epitelial cells (CELLS); Appearance (APP), Color (COLOR).

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (see Table 2)
HISTOPATHOLOGY: Yes (see Table 2)

Statistics:

please see Table 1

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Dermal irritation:

effects observed, treatment-related

Description (incidence and severity):

females

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not specified

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

not specified

Ophthalmological findings:

not specified

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Description (incidence and severity):

higher urea and creatinine levels in females were compared with literature data and considered to be within the normal fluctuation range.

Urinalysis findings:

no effects observed

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

not specified

Histopathological findings: neoplastic:

no effects observed

Description (incidence and severity):

A mammary carcinoma was recorded in a female treated at 1000 mg/kg/day. The process leading to tumor demands several weeks or months. A relationship to treatment given for 2 weeks was therefore excluded.

Details on results:

CLINICAL SIGNS AND MORTALITY
No effects

BODY WEIGHT AND WEIGHT GAIN
No effects

FOOD CONSUMPTION
No effects

FOOD EFFICIENCY
No data

WATER CONSUMPTION
No data

OPHTHALMOSCOPIC EXAMINATION
No data

HAEMATOLOGY
No effects

CLINICAL CHEMISTRY
Higher urea and creatinine levels in females were compared with literature data and considered to be within the normal fluctuation range.

URINALYSIS
No effects

NEUROBEHAVIOUR
Not examinated

ORGAN WEIGHTS
No effects

GROSS PATHOLOGY
No effects

HISTOPATHOLOGY: NON-NEOPLASTIC
No data

HISTOPATHOLOGY: NEOPLASTIC (if applicable)
A mammary carcinoma was recorded in a female treated at 1000 mg/kg/day. The process leading to tumor demands several weeks or months. A relationship to treatment given for 2 weeks was therefore excluded.

Effect levels

1

Key result

Dose descriptor:

NOEL

Effect level:

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

Based on:

test mat.

Sex:

male

Basis for effect level:

other:

Remarks on result:

not determinable due to absence of adverse toxic effects

2

Key result

Dose descriptor:

NOEL

Effect level:

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

Based on:

test mat.

Sex:

female

Basis for effect level:

other: very slight to well-defined erythema, were observed in 3/5 females, and scab formations at the application site were observed in one female

3

Dose descriptor:

LOAEL

Remarks:

local

Effect level:

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

Based on:

test mat.

Sex:

female

Basis for effect level:

other: very slight to well-defined erythema in 3 out of 5 females and scab formations at the application site in one female

4

Dose descriptor:

LOAEL

Remarks:

local

Effect level:

8 mg/cm² per day

Based on:

test mat.

Sex:

female

Basis for effect level:

other: assuming 330 g bw of rat and 41.8 cm^2 body surface, 10 % exposed area

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

Under the experimental conditions of this study, the NOEL was considered to be 1000 mg of Mexoryl SBO/kg bw/day in males and 500 mg of Mexoryl SBO/kg bw/day in females. The local LOAEL was considered to be 1000 mg of Mexoryl SBO/kg bw/day in females.

Executive summary:

The GLP compliant study was based on the OECD TG 410, however, the potential toxicity of the test item following daily cutaneous application to rats was conducted during 2 weeks and not during 21/28 days as it is recomended in the guideline.

During phase I, three treated groups (groups 2 to 4) of five male and five female Sprague-Dawley rats received the test item by daily cutaneous application at dose-levels of 250, 500 or 1000 mg/kg/day for 2 weeks. The test item was supplied "ready-to-use" and administered under dosage-volumes of 0.236, 0.472 and 0.943 mL/kg/day, respectively. A group of five males and five females received the control item (purified water) under the same experimental conditions and acted as a control group (group 1). Due to a technical issue with the material used for the administration to group 3 males and to group 4 males and females, and based on the absence of toxic effects noted in the males at 1000 mg/kg/day during phase I, an additional control group (group 5) and an additional high-dose group (group 6) were treated under the same experimental conditions as groups 1 and 4 (phase II). The results of group 4 animals are presented for information, but the group 6 results are considered to be the representative results of daily administration at 1000 mg/kg/day. The dosage form was applied to the dorsum, over an area of approximately 10% of the total body surface. The animals wore a protective collar over a period of at least 6 hours after each application in order to avoid ingestion of the test item. After the exposure period, the application site was cleaned using tap water and dried with cotton wool. The animals were checked twice daily for mortality, and clinical signs were observed once a day. The body weight of each animal was recorded once before the beginning of the study, then on the first day of treatment and on days 4, 8, 11 and 14. Food consumption was recorded once a week during the study. On completion of the treatment periods, hematology, blood biochemistry and urinalysis investigations were performed before sacrifice and the animals were examined macroscopically. Designated organs were weighed and selected tissues were preserved. A microscopic examination of designated organs was performed.

No treatment-related findings were noted at 250 or 500 mg/kg/day. During phase II, the following findings at 1000 mg/kg/day were considered to be test item-related: local reactions, including very slight to well-defined erythema, were observed in 3/5 females, and scab formations at the application site were observed in one female. At this dose-level, increased urea (+17%) and creatinine (+10%) levels were recorded in the females. However applicant consider these urea and creatinine data as not treatment-related, since literature source (Handbook of toxicology) show the fluctuation of these parameters within a normal permissible range. Microscopic findings consisted of acanthosis, observed in most of the control and treated animals; it was most probably secondary to clipping and thus of no toxicological importance.

No treatment-related findings were recorded at 250 or 500 mg/kg/day. At 1000 mg/kg/day test item-related findings of minimal to slight intensity at the application site were recorded in females only. Consequently, under the experimental conditions of this study, the NOEL (No Observed Effect Level) was considered to be 1000 mg of Mexoryl SBO/kg/day in males and 500 mg of are not part of the disclosed dossier information by ECHA/kg/day in females. The local LOAEL was considered to be 1000 mg of Mexoryl SBO /kg bw/day in females.