Registration Dossier

Administrative data

Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
6 February - 3 June 2008
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

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

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EPA OPPTS 870.1200 (Acute Dermal Toxicity)
Deviations:
no
Qualifier:
according to
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
Deviations:
no
GLP compliance:
yes
Test type:
fixed dose procedure
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Specific details on test material used for the study:
- Lot No. of test material: 07-170-FIL-2/3
- Appearance: White powder
- Expiration date: May 2010
- Purity: 98.4%
- Storage condition of test material: Room temperature

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Texas Animal Specialties, Humble, TX
- Females nulliparous and non-pregnant: yes
- Age at study initiation: Approx. 9 weeks old
- Weight at study initiation: Males 239 - 304 g; Females 165 - 219 g
- Fasting period before study: No
- Housing: Suspended, wire bottom, stainless steel cage; 1 animal per cage
- Diet: PMI Feeds Inc. Formulab #5008 available ad libitum
- Water: Municipal water supply available ad libitum from automatic water system
- Acclimation period: Not specified

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3°C
- Humidity (%): 30 - 70%
- Air changes (per hr): 10 - 12 air changes/ hour
- Photoperiod (hrs dark / hrs light): 12 hour light/dark cycle

IN-LIFE DATES: From: 27 February 2008 To: 13 March 2008

Administration / exposure

Type of coverage:
semiocclusive
Vehicle:
water
Details on dermal exposure:
TEST SITE
- Area of exposure: The test material was applied to the dorsal surface of the trunk in a thin uniform layer.
- % coverage: Not less than 10% of the total body surface area was clipped
- Type of wrap if used: The area of application was covered with a 5 x 10 cm surgical gauze patch and secured with non-irritating adhesive tape. The trunk of each animal was then wrapped with vet wrap which was secured in place with non-irritating adhesive tape to prevent possible ingestion of the test substance.

REMOVAL OF TEST SUBSTANCE
- Washing: The test sites were gently washed with room temperature tap water and a clean cloth to remove as much residual test material as possible.
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): The dose amount was 1.21 - 1.54 g in males and 0.823 - 1.01 g in females.
- Concentration (if solution): An individual dose was calculated for each animal based on its Day 0 bodyweight just before exposure.
- Constant volume or concentration used: no
- For solids, paste formed: The test material was moistened with water.

VEHICLE
- Concentration (if solution): Each dose was moistened with a sufficient amount of deionised water at a concentration of 1.0 mL/g of test substance.
Duration of exposure:
24 hours exposure to test material
Doses:
5050 mg/kg
No. of animals per sex per dose:
5 animals/ sex
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations for mortality and clinical/ behavioural signs of toxicity: 2-3 times on the day of exposure (Day 0) and at least once daily thereafter for 14 days
- Frequency of weighing: Individual body weights were recorded just prior to dosing and on days 7 and 14.
- Frequency of dermal irritation observations: approximately 60 minutes after removal of wrappings and on Days 4, 7, 11 and 14.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, gross necropsy

Results and discussion

Effect levels
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 5 050 mg/kg bw
Based on:
test mat.
Remarks on result:
no indication of skin irritation up to the relevant limit dose level
Mortality:
There was no mortality during the study.
Clinical signs:
All animals appeared normal for the duration of the study. Irritation included very slight erythema in one animal on Day 1.
Body weight:
All animals exhibited normal weight gain during the post treatment observation period.
Gross pathology:
The gross necropsy conducted at termination of the study revealed no observable abnormalities.
Other findings:
- Actual temperature: 20 - 24°C
- Actual relative humidity: 27 - 90% (Humidity was outside of the protocol range but did not affect the study outcome)

Any other information on results incl. tables

Table 1: Body weights, time of death and gross necropsy (Dose level 5050 mg/kg)

Animal No.

Dose amount (g)

Body weights (g)

Time of death*

Gross necropsy findings

Day 0

Day 7

Final

251-M

1.21

239

269

284

Day 14

No observable abnormalities

252-M

1.42

282

311

337

Day 14

No observable abnormalities

253-M

1.45

288

318

342

Day 14

No observable abnormalities

254-M

1.41

279

315

346

Day 14

No observable abnormalities

255-M

1.54

304

336

349

Day 14

No observable abnormalities

256-F

0.944

187

198

207

Day 14

No observable abnormalities

257-F

0.914

181

196

212

Day 14

No observable abnormalities

258-F

1.01

200

215

227

Day 14

No observable abnormalities

259-F

1.01

219

237

249

Day 14

No observable abnormalities

260-F

0.823

165

177

189

Day 14

No observable abnormalities

* Day of dosing is Day 0; Day 14 is terminal sacrifice

M – Male

F – Female

Note: Animal 259 dose amount should have been 1.11 g

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
The acute dermal LD50 of the test substance, Formononetin, is estimated to be greater than 5050 mg/kg in males and females.