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Administrative data

Description of key information

2 year Dermal NOAEL: >= 1000 mg/kg bw/day

Key value for chemical safety assessment

Carcinogenicity: via oral route

Endpoint conclusion
Endpoint conclusion:
no study available

Carcinogenicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Carcinogenicity: via dermal route

Link to relevant study records
Reference
Endpoint:
carcinogenicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study
Reason / purpose for cross-reference:
reference to same study
Qualifier:
according to guideline
Guideline:
OECD Guideline 451 (Carcinogenicity Studies)
GLP compliance:
yes (incl. QA statement)
Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories France (l’Arbresle, France)
- Age at study initiation: approximately 7 weeks
- Weight at study initiation: 231 g (range: 194 to 285 g) for the males and 180 g (range: 143 to 215 g) for the females
- Fasting period before study: None reported
- Housing: individually in suspended wire-mesh cages (43.0 x 21.5 x 18.0 cm); autoclaved sawdust
- Diet (e.g. ad libitum): A04 C pelleted maintenance diet [SAFE, Villemoisson, Epinay-sur-Orge, France], ad libitum
- Water (e.g. ad libitum): tap (filtered with a 0.22 µm filter), ad libitum
- Acclimation period: 15 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2
- Humidity (%): 50 ± 20
- Air changes (per hr): 12
- Photoperiod (hrs dark / hrs light): 12h/12h (7:00 - 19:00)

IN-LIFE DATES: From: 9 Sept. 2003; To: 22 Sept. 2005
Route of administration:
dermal
Vehicle:
polyethylene glycol
Remarks:
PEG 400
Details on exposure:
TEST SITE
- Area of exposure: dorsum
- % coverage: 10
- Type of wrap if used: none
- Time intervals for shavings or clipplings: as needed, but not less than once per week.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): cotton swab moistened with water
- Time after start of exposure: before each dosing

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2.5 mL/kg-day
- Concentration (if solution): 40, 200, and 400 mg/mL
- Constant volume or concentration used: yes
- For solids, paste formed: yes (cream-like consistency)

VEHICLE
- Justification for use and choice of vehicle (if other than water): solubility / stability
- Lot/batch no. (if required): various
- Purity: no data

USE OF RESTRAINERS FOR PREVENTING INGESTION: none reported
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
The concentration was determined by HPLC on samples taken from each dosage form (including the control) prepared for use in weeks 1, 13, 26, 40, 52, 66, 78, 92 and 104.
Duration of treatment / exposure:
104 weeks
Frequency of treatment:
Daily
Post exposure period:
None
Remarks:
Doses / Concentrations:
0, 100, 500, 1000 mg/kg-bw/day
Basis:
other: nominal applied dose
No. of animals per sex per dose:
100
Control animals:
yes, concurrent no treatment
yes, concurrent vehicle
Details on study design:
Dose selection rationale:

Tinosorb S was not bioavailable. A dermal ADME test in rats did not show sufficient absorption of Tinosorb S to enable calculation of the AUC. The dose of 1000 mg/kg/day was tested dermally in rats for 13 weeks (CIT/Study No. 25378 TCR): (1) dosage formulation concentration was 400 mg Tinosorb S/mL vehicle (ca. 40% mixture) and was cream-like in consistency, (2) easily applied by syringe at the administration site (10% of body surface area), gave full, layered coverage to the administration site, no adverse effects related to Tinosorb S occurred. Testing a higher dose (up to 1500 mg Tinosorb S/kg bodyweight/day) was not practical or technically achievable: dose formulations of 500 mg Tinosorb S/mL and 600 mg/mL were prepared and found to be of a satisfactory consistency. However, they were much too viscous (less spreadable) and could not be applied to the administration site conveniently or effectively. Testing dermal dosages higher than 1000 mg/kg/day gave no added advantage: (1) a higher amount of Tinosorb S was not necessarily in contact with epidermis, (2) applying a thicker layer of dose form to the skin did not achieve a higher systemic dose.
Positive control:
None
Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Once daily

DERMAL IRRITATION (if dermal study): Yes
- Time schedule for examinations: from day 1 to week 4 inclusive, before each application.

BODY WEIGHT: Yes
- Time schedule for examinations: once before group allocation, on the first day of treatment, once a week during the first 13 weeks of the treatment period, then once every 4 weeks, and in week 105 on completion of the treatment period.

FOOD CONSUMPTION:
- Food consumption for each animal: Yes
- Time schedule: once a week during the first 13 weeks of the treatment period and then once every 4 weeks until the end of the study.

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

WATER CONSUMPTION: No

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: all animals before the beginning of the treatment period and on 10 animals/sex from groups 2 and 5 in weeks 26, 52, 78 and 103.

HAEMATOLOGY: Yes
- Time schedule for collection of blood: during weeks 52 and 78, and week 105.
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: No
- How many animals: all animals, except week 105 only 10 surviving animals per sex per dose group.
- Parameters attached: yes

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: week 105
- Animals fasted: Yes, at least 14 hours overnight
- How many animals: 10 surviving per sex per dose group.
- Parameters attached: yes

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: No

OTHER: Blood samples for the determination of plasma levels of the test item were taken in order to check possible exposure to the test item at the following time-points: (1) in weeks 13, 26, 52, 78 and 104, and (2) one time-point (before daily dosing): five animals/sex and group on each sampling occasion.
Sacrifice and pathology:
GROSS PATHOLOGY: Yes, a complete macroscopic post-mortem examination was performed on all study animals. This included examination of the external surfaces, all orifices, the cranial cavity, the external surfaces of the brain and spinal cord, the thoracic, abdominal and pelvic cavities with their associated organs and tissues and the neck with its associated organs and tissues.

HISTOPATHOLOGY: Yes, a microscopic examination was performed on all animals.

PARAMETERS ATTACHED: Yes
Statistics:
The statistical analysis of tumor data was performed according to the methods described by Peto et al. (1980), taking into account between-group variation in intercurrent mortality, and whether a tumor was considered fatal or not. Each treated group was separately compared with the control group, and tests were made for heterogeneity and for dose-related trend. See attached diagram.
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
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
no effects observed
Haematological findings:
no effects observed
Clinical biochemistry findings:
no effects observed
Urinalysis findings:
no effects observed
Behaviour (functional findings):
not examined
Organ weight findings including organ / body weight ratios:
no effects observed
Gross pathological findings:
effects observed, treatment-related
Histopathological findings: non-neoplastic:
effects observed, treatment-related
Histopathological findings: neoplastic:
no effects observed
Details on results:
Scabs were seen on the application site at a higher incidence and severity in males treated at 100 mg/kg/day and in animals treated at 500 and 1000 mg/kg/day, without clear dose-relationship between 500 and 1000 mg/kg/day. In addition, the scabs appeared earlier in animals treated at 500 and 1000 mg/kg/day. Among decedent animals, a higher incidence of scabs, scars or sores was seen at the treated skin area and/or at various other skin locations in all test-treated male groups or females treated at 500 and 1000 mg/kg/day. At terminal sacrifice, there was a higher incidence of scabs at the treated skin area in males treated at 500 and animals treated at 1000 mg/kg/day.

At the treated skin, a dose-related pattern of epidermal injury, accompanied by inflammatory and progressive changes, was observed that was considered to be indicative of a chronic and moderate local skin irritation, caused by long-term exposure to the test item dosage form (Greaves, 2000; Klein-Szanto and Conti, 2002). Test item-related effects at the untreated skin were very minor and interpreted as consequence of an unintentional contamination with the test item dosage forms, e.g. by licking or scratching. Diffuse sebaceous gland hypertrophy/hyperplasia, observed at the treated skin and -to a very minor degree- at the untreated skin from 100 mg/kg/day is a well-known effect of chronic exposure to locally irritant chemical agents (Klein-Szanto and Conti, 2002). In the present study, although less prominent, an increased incidence of diffuse sebaceous gland hypertrophy/hyperplasia was also seen at the application site of animals treated with the vehicle only, thus underlining the unspecific character of this reactive change. There were no non-neoplastic findings which were attributed to treatment with the test item at any dose-levels, in the other tissues.

The systemic exposure of the animals seemed similar in the different treated groups and remained at very low levels despite the high applied dose-levels.
Relevance of carcinogenic effects / potential:
Not carcinogenic following daily dermal exposures up to 1000 mg/kg-bw/day for 104 weeks in male and female rats.
Dose descriptor:
NOAEL
Effect level:
>= 1 000 mg/kg bw/day (nominal)
Based on:
test mat.
Sex:
male/female
Remarks on result:
other: Effect type: carcinogenicity (migrated information)
Conclusions:
The daily treatment with the test item for 104 weeks induced only non-neoplastic findings at the treated skin area indicative of a chronic and moderate local skin irritation and substantiated that higher doses could not have been used. Consequently, under the experimental conditions of the study, the test item, FAT 70’884/C, was not carcinogenic by cutaneous application at 100, 500 and 1000 mg/kg/day.
Executive summary:

Three test-treated groups of 100 Wistar Han rats (50 males and 50 females) received the test item, FAT 70’884/C (batch No. 02464CL3), at 100, 500 or 1000 mg/kg/day by daily cutaneous application for 104 weeks (under a dosage volume of 2.5 mL/kg/day). Another group of 50 males and 50 females received no treatment and acted as an untreated control group. An additional group of 50 males and 50 females received the vehicle alone (polyethylene glycol 400) under the same experimental conditions and acted as vehicle control group. The animals were checked daily for mortality, clinical signs and possible signs of skin irritation. The animals were palpated every 2 weeks after 6 months of treatment in order to monitor the onset and progression of any masses. Body weight and food consumption were recorded at designated intervals (weekly during the first 3 months of treatment and then monthly). Ophthalmological examinations were performed on all the animals before the beginning of the treatment period and on 10 animals/sex in the vehicle control and high-dose groups in weeks 26, 52, 78 and 103. The differential white cell count was determined in weeks 52 and 78 for the animals in the vehicle control and high-dose groups. Blood samples for the determination of plasma levels of the test item were taken in weeks 13, 26, 52, 78 and 104. On completion of the treatment period, blood samples were taken from 10 animals/sex and group for hematology and blood biochemistry investigations. All surviving animals were euthanized and submitted to a macroscopic post-mortem examination. Designated organs and any masses or lesions were sampled from each animal and retained for microscopic examination.

 

There was no effect of the test item on survival rate during the 104-week treatment period.

 

The incidence, nature and time of onset of the clinical signs observed in test-treated animals during the study period were similar to those observed in control animals.

 

Scabs were seen on the application site at a higher incidence and severity in males treated at 100 mg/kg/day and in animals treated at 500 and 1000 mg/kg/day, without clear dose-relationship between 500 and 1000 mg/kg/day. In addition, the scabs appeared earlier in animals treated at 500 and 1000 mg/kg/day.

 

The palpable masses observed during the treatment period were considered to be of a spontaneous nature and usual for animals of this strain and age. They were not attributed to treatment with the test item.

 

The body weight and food consumption were unaffected by treatment with the test item at all dose-levels during the study.

 

No ophthalmological findings were attributed to treatment with the test item at any dose-level.

 

No hematological or blood biochemical differences were attributed to treatment with the test item.

 

The systemic exposure of the animals seemed similar in the different treated groups and remained at very low levels despite the high applied dose-levels.

 

There were no relevant differences between control and test-treated animals at any dose-levels.

 

Among decedent animals, a higher incidence of scabs, scars or sores was seen at the treated skin area and/or at various other skin locations in all test-treated male groups or females treated at 500 and 1000 mg/kg/day. At terminal sacrifice, there was a higher incidence of scabs at the treated skin area in males treated at 500 and animals treated at 1000 mg/kg/day.

 

Treatment did not induce any neoplastic changes at the site of topical application. The overall incidence of systemic neoplastic findings in all other tissues examined did not indicate any treatment-related increase.

 

At the treated skin, a dose-related pattern of epidermal injury, accompanied by inflammatory and progressive changes, was observed that was considered to be indicative of a chronic and moderate local skin irritation, caused by long-term exposure to the test item dosage form (Greaves, 2000; Klein-Szanto and Conti, 2002). Test item-related effects at the untreated skin were very minor and interpreted as consequence of an unintentional contamination with the test item dosage forms, e.g. by licking or scratching. Diffuse sebaceous gland hypertrophy/hyperplasia, observed at the treated skin and -to a very minor degree- at the untreated skin from 100 mg/kg/day is a well-known effect of chronic exposure to locally irritant chemical agents (Klein-Szanto and Conti, 2002). In the present study, although less prominent, an increased incidence of diffuse sebaceous gland hypertrophy/hyperplasia was also seen at the application site of animals treated with the vehicle only, thus underlining the unspecific character of this reactive change.

 

There were no non-neoplastic findings which were attributed to treatment with the test item at any dose-levels, in the other tissues.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
1 000 mg/kg bw/day
Study duration:
chronic
Species:
rat

Justification for classification or non-classification

Based on the absence of carcinogenic activity in a 2-year dermal study, Bemotrizinol would not be classified as a carcinogen under either the EU DSD classification system (EU Directive 67/548/EEC) or the EU CLP classification system (EU Regulation 1272/2008).

Additional information

The daily treatment with the test item for 104 weeks induced only non-neoplastic findings at the treated skin area indicative of a chronic and moderate local skin irritation and substantiated that higher doses could not have been used. Consequently, under the experimental conditions of the study, the test item, Bemotrizinol, was not carcinogenic by cutaneous application at 100, 500 and 1000 mg/kg/day (CIT, 2006)