Registration Dossier

Administrative data

Endpoint:
short-term repeated dose toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2 October 2007 to 14 January 2008
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2008
Report Date:
2008

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 410 (Repeated Dose Dermal Toxicity: 21/28-Day Study)
Deviations:
yes
Remarks:
Only 8% of the body surface was covered
GLP compliance:
no
Remarks:
The study was not commissioned with compliance with REACH as a goal, rather the study was commissioned during early product development.
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Q14A-14
- Purity: 99%

Test animals

Species:
rat
Strain:
other: Crl:CD(SD)
Details on species / strain selection:
The Sprague-Dawley rat was used because it is a widely used strain for which significant historical control data are available.
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories, Inc., Raleigh, North Carolina
- Females nulliparous and non-pregnant: yes
- Age at study initiation: The animals were approximately 58 days old at the initiation of dose administration.
- Weight at study initiation: individual body weights ranged from 260 g to 298 g for males and from 190 g to 220 g for females.
- Housing: housed individually
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 10 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 68.2°F to 70.6°F (20.1°C to 21.4°C)
- Humidity (%): 33.6% to 52.2%
- Air changes (per hr): minimum of 10 fresh air changes per hour.
- Photoperiod (hrs dark / hrs light): 12 / 12

IN-LIFE DATES: From: 10 October 2007 To: 9 November 2007

Administration / exposure

Type of coverage:
occlusive
Vehicle:
unchanged (no vehicle)
Details on exposure:
The test was conducted as non-GLP study. The test substance at the level of 0.91 mL/kg bw (equivalent to 1,300 mg/kg bw based on the density of 1.432 g/mL) was dosed to individual animals via dermal application to clipped dorsum under occlusive conditions once daily for a minimum of 6 hours per day for 28 consecutive days.
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Samples were typically within 4% of expected concentration. Examination of the HPLC chromatograms showed OFPMA eluting near 1.55 minutes as expected, and revealed no incipient peaks.
Duration of treatment / exposure:
A minimum of 6 hours per day for 28 consecutive days.
Frequency of treatment:
28 consecutive days
Doses / concentrations
Dose / conc.:
1 300 mg/kg bw/day (nominal)
No. of animals per sex per dose:
10/sex/dose
Control animals:
yes
Positive control:
None

Examinations

Observations and examinations performed and frequency:
All animals were observed twice daily for mortality and moribundity. Clinical examinations were performed daily. Detailed clinical examinations were performed weekly.
Sacrifice and pathology:
Pathology evaluations were performed on all animals on the day of scheduled necropsy (Day 28 of the study). Complete necropsies were conducted on all animals.
Other examinations:
Application sites were examined once per week at the time of the detailed physical examination and treated and untreated skin was examined macroscopically and microscopically. Individual body weights and food consumption were recorded weekly. Ophthalmic examinations were performed during study weeks -2 and 3. Blood and urine samples for clinical pathology evaluations (hematology, coagulation, serum chemistry and urinalysis) were collected from all animals on the day of the scheduled necropsy (study day 28).
Statistics:
All statistical tests were performed using appropriate computing devices or programs.

Results and discussion

Results of examinations

Clinical signs:
effects observed, non-treatment-related
Description (incidence and severity):
There were no test substance-related effects noted on clinical findings, including dermal observations.
Dermal irritation:
effects observed, non-treatment-related
Description (incidence and severity):
There were no test substance-related effects noted on clinical findings, including dermal observations.
Mortality:
mortality observed, non-treatment-related
Description (incidence):
One male in test group was found dead on Day 13 of the study. The cause of the death was undetermined. Due to lack of significant indication of toxicity in the treated animals, this death was considered by the study authors to be likely not test substance related
Body weight and weight changes:
effects observed, non-treatment-related
Description (incidence and severity):
There were no test substance-related effects noted on body weights.
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:
effects observed, non-treatment-related
Description (incidence and severity):
There were no test substance-related effects noted in haematology or coagulation parameters.
Clinical biochemistry findings:
effects observed, treatment-related
Description (incidence and severity):
Lower total protein (-5%) and globulin (-9%) levels were recorded as treatment related alterations in serum chemistry parameters in the test substance treated males. The values for the total protein and globulin were within historical control ranges for the laboratory and hence study authors considered the alterations as non-adverse.
Urinalysis findings:
no effects observed
Description (incidence and severity):
There were no test substance-related effects noted in urinalysis parameters.
Behaviour (functional findings):
not examined
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
effects observed, non-treatment-related
Description (incidence and severity):
One statistically significant difference was observed when the vehicle control and test article-treated groups were compared. Mean thymus relative to final body weight was lower (13.4%) than the vehicle control group in the treated group males but was within the WIL historical control range (version 2.4) for male rats 9-12 and 13-15 weeks of age. This alteration was a function of a slightly lower (but also within the historical control ranges) mean absolute thymus weight and slightly higher mean final body weight in the treated group males and not an effect of test article administration.
Gross pathological findings:
effects observed, non-treatment-related
Description (incidence and severity):
White area(s) were seen in the liver from 1 of 10 males and females in the treated group compared to none in the vehicle control group. These foci correlated to areas of hepatocellular necrosis seen histologically. However, smaller foci of necrosis, that went undetected at necropsy, were seen microscopically in vehicle control group rats, indicating that the white areas and hepatocellular necrosis were incidental changes unrelated to test article administration.
Neuropathological findings:
not examined
Histopathological findings: non-neoplastic:
effects observed, non-treatment-related
Description (incidence and severity):
There were no test substance related effects noted in selected organs and microscopic tissue samples. Minimal to mild acute inflammation of the urinary bladder was observed in 2 of 10 test substance treated females and was considered by the study authors to be related to the administration of the test substance and to be non-adverse. No test substance related microscopic findings were noted on treated skin tissues.
Histopathological findings: neoplastic:
not examined
Other effects:
not examined

Effect levels

Key result
Dose descriptor:
NOAEL
Effect level:
1 300 mg/kg bw/day (nominal)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: No adverse effects noted at the dose level of 1300 mg/kg bw/day via dermal route

Target system / organ toxicity

Critical effects observed:
no

Applicant's summary and conclusion

Conclusions:
Repeated dermal application of test substance to rats for 6 hours daily for 28 consecutive days was well-tolerated with no physical observations of toxicity. Evidence of systemic, non-adverse effects attributable to the test article was limited to lower total protein and lower globulin in treated males on study day 28. Although, the microscopic finding of minimal or mild acute inflammation of the urinary bladder observed in 2 treated females is considered to be related to test article administration, it does not appear to be adverse.
Executive summary:

The test article was administered via dermal application to clipped dorsum (approximately 8% of total body surface area) once daily for a minimum of 6 hours per day for 28 consecutive days to 1 group (Group 2) of rats. The application site for each animal was covered with 8-ply gauze, covered with an occluded non-porous latex bandage and held in place with non-irritating tape. Elizabethan collars were applied to restrict access to the wrapped dosing site. The dosage level was 1300 mg/kg/day. A concurrent vehicle control group (Group 1) received the vehicle on a comparable regimen. The dose volume was 1.3 mL/kg for Group 1 and 0.91 mL/kg for Group 2. Each group consisted of 10 animals/sex. Following 28 days of dose administration, all animals were euthanized and necropsied.

 

All animals were observed twice daily for mortality and moribundity. Clinical examinations were performed daily, and detailed physical examinations were performed weekly. Application sites were examined once per week at the time of the detailed physical examination and treated and untreated skin was examined macroscopically and microscopically. Individual body weights and food consumption were recorded weekly. Ophthalmic examinations were performed during study weeks -2 and 3. Clinical pathology evaluations (hematology, coagulation, serum chemistry and urinalysis) were performed on all animals on the day of the scheduled necropsy (study day 28). Complete necropsies were conducted on all animals, and selected organs were weighed at the scheduled necropsy. Selected tissues were examined microscopically from all animals.

In the test article-treated group, one male was found dead on study day 13. While the cause of death was undetermined, due to overall lack of significant indications of toxicity in the treated animals, this death was probably not test article-related. There were no test article-related effects on clinical findings, including dermal observations, nor any test article-related effects on body weights, food consumption, hematology, coagulation or urinalysis parameters or organ weights were noted. There were no test article-related macroscopic findings. There were no test article-related microscopic findings on treated skin.

 

Test article-related non-adverse alterations in serum chemistry parameters included lower total protein and glucose levels in the treated males when compared to the vehicle control group. A test article-related but non-adverse microscopic finding was minimal or mild acute inflammation of the urinary bladder observed in 2 treated females.

Repeated dermal application of test substance to rats for 6 hours daily for 28 consecutive days was well-tolerated with no physical observations of toxicity. Evidence of systemic, non-adverse effects attributable to the test article was limited to lower total protein and lower globulin in the treated males on study day 28. Although, the microscopic finding of minimal or mild acute inflammation of the urinary bladder observed in 2 treated females is considered to be related to test article administration, it does not appear to be adverse.