Registration Dossier

Administrative data

Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
8 June to 18 August 2010
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP-Study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report Date:
2010

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.3 (Acute Toxicity (Dermal))
Deviations:
no
GLP compliance:
yes
Test type:
standard acute method
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): "3-hydroxy-2-(hydroxymethyl)-2-methylpropionaldehyde"
- Molecular formula (if other than submission substance): C5H10O3
- Physical state: Colourless, high viscous
- Composition of test material, percentage of components: ~ 82 % Dimethylpropanale, ~ 10 % Hydroxyethanesulfonic acid, Na-salt (CAS No.: 870-72-4), ~ 6 % water, ~ 2 % Potassiumformiate (CAS No.: 590-29-4)
- Lot/batch No.: CH 138067/001
- Expiration date of the lot/batch: 30 November 2010
- Stability under test conditions: Min. 1 year
- Storage condition of test material: Room temperature

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
Species, strain: Rats, Crl:CD(SD).
Supplier: Charles River Deutschland GmbH, D-97633 Sulzfeld.
Number of animals and sex: 5 males and 5 females, females were nulliparous and non-pregnant.
Age: Approximately 8 weeks (males) and 12 weeks (females) at the time of administration.
Health conditions: A health inspection was performed prior to the commencement of treatment to ensure, that the animals were in a good state of health. Special attention was paid to the skin to be treated, which was intact and free from any abnormality.
Hygienic status: Optimal hygienic conditions.
Room number: EH1-23.
Room temperature: Ranges from 19.93 to 21.90 °C (continuous control and recording).
Relative humidity: Ranges from 40.91 to 73.72 % (continuous control and recording).
Air exchange: 12 per hour.
Light: Artificial light from 6 a.m. to 6 p.m.
Cages: Single caging in Makrolon cages type III (37.5 cm x 21.5 cm bottom area, 18 cm height). Wire mesh lids. Sanitation of cages once a week.
Bedding material: Aspen wood chips, Fa. ABEDD Dominik Mayr KEG, A-8580 Köflach, autoclaved. Random samples of the bedding material are analysed for contaminants by the supplier. Changes 1 / week.
Environmental enrichment: Nibbling wood bricks (10 cm x 2 cm x 2 cm) and nesting material, both from the same material and source as the bedding material, were offered to the animals once a week.
Feed: Ssniff R/M-H maintenance diet for rats and mice (item V1534-300) ad libitum, supplied by Ssniff Spezialdiäten GmbH, 59494 Soest, Germany. Analysis of the feed for ingredients and contaminants is performed randomly by Ssniff.
Water: Tap water, from an automatic watering system, ad libitum, random samples of the water are analysed by the "AGES", A-1226 Vienna, to check, if the water fulfils the requirements for drinking water for humans.
Identification: Labelling with felt-tipped pen on the tail and on the cage.
Acclimatisation: At least 7 days.

Administration / exposure

Type of coverage:
semiocclusive
Vehicle:
unchanged (no vehicle)
Details on dermal exposure:
A single dermal administration was performed by spreading the test substance on an area of at least 10 % of the estimated body surface:
The body surface was calculated using the formula: body surface (cm²) = 10 x body weight (g)2/3
The test site was located on the dorsal thoracic region. An area of 6.5 cm x 8 cm (52 cm2) was marked on a relaxed animal.
The hair of the dorsal trunk was clipped with an electrical hair clipper (Aesculap GH, 0.1 mm cutter head) one day before application of the test substance. The amounts of the test substance were calculated and weighed for each individual using the body weights determined on the day of the administration.
A cellulose patch (Pehazell, Hartmann AG) with the calculated amount of the test substance on the surface and soaked with deionised water to get optimal contact with the skin, was applied to the test site and held in place by fixing marginally with non irritating tape (Blenderm Wundpflaster, 3M).
The test site was covered by a semi-occlusive dressing (Fixomull Stretch, Fa. Beiersdorf).
The duration of exposure was 24 hours.
At the end of the exposure period the dressing, the tape and the patch were removed.
Residual test substance was wiped off using wet cellulose tissue, if necessary.
Duration of exposure:
24 hours
Doses:
2000 mg/kg body weight
No. of animals per sex per dose:
5
Control animals:
not required
Details on study design:
Observations were performed 0 - 0.5, > 0.5 - 1, > 1 - 2, > 2 - 4 and > 4 - 6 hours after administration of the test substance (p.a.) and then at least once a day for a total of 14 days. Observations included but were not limited to changes in skin, fur, eyes, the occurrence of secretions and excretions, autonomic activity, changes in gait, posture and the presence of convulsions.
No skin examination of the administration site was possible during the exposure period, while it was covered by the patch and wrappings.

Body weights were determined
• before administration.
• 7 days p.a.
• 14 days p.a.
Body weight gain was calculated for each week of the study, i.e. between
• 0 and 7 days p.a.
• 7 and 14 days p.a.

All animals were sacrificed by inhalation of 80 % CO2 + 20 % O2 14 days p.a. and subjected to a necropsy including a gross pathological examination.

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Mortality:
All animals survived until the scheduled termination of the study.
Clinical signs:
General findings: All animals but one male did not show any clinical signs during the entire observation period.
Chromodacryorrhoea was noted in one male from 4 h until 6 h p.a. This might be due to the discomfort, caused by the dressing and was not considered to be toxicologically relevant.
Observations of skin condition: A yellow staining of the skin was observed in all animals from 1 d until a maximum of 14 d p.a. This stain is attributed to a staining property of the test substance and not considered to be a toxic effect. No other alterations to the exposed skin by the test substance were found.
Body weight:
All animals gained weight in both weeks p.a.
Gross pathology:
No abnormal findings were made in the animals at terminal necropsy.

Any other information on results incl. tables

Table: Body weights and body weight gain.

Individual data, mean and standard deviation SD.

 

Dose

Animal

Body weight (g)

Body weight gain (g)

Sex

No.

before
administr.

7 days
p.a.

14 days
p.a.

death

0-7 days
p.a.

7-14 days
p.a.

 

11

272

313

354

-

41

41

2000 mg/kg

12

287

339

393

-

52

54

male

13

283

310

345

-

27

35

 

14

270

312

355

-

42

43

 

15

272

304

343

-

32

39

 

mean

276.8

315.6

358.0

-

38.8

42.4

 

SD

7.7

13.5

20.3

-

9.7

7.1

 

16

239

249

267

-

10

18

2000 mg/kg

17

230

242

255

-

12

13

female

18

229

237

247

-

8

10

 

19

227

257

263

-

30

6

 

20

237

247

260

-

10

13

 

mean

232.4

246.4

258.4

-

14.0

12.0

 

SD

5.3

7.5

7.7

-

9.1

4.4

Table: Observations in life.

Findings

Dose
(mg / kg), sex

No. of the affected animals

Observation time
(p.a.)
   first      last

chromodacryorrhoea

2000, m

11

4 h - 6 h

test substance related stain of skin

2000, m

11

1 d - 14 d

 

 

12

1 d - 14 d

 

 

13

1 d - 12 d

 

 

14

1 d - 12 d

 

 

15

1 d - 14 d

 

2000, f

16

1 d - 13 d

 

 

17

1 d - 14 d

 

 

18

1 d - 12 d

 

 

19

1 d - 12 d

 

 

20

1 d - 14 d

Table: Necropsy findings.

SYSTEM
Organ, finding

Dose
(mg / kg)
sex

No. of affected
animals

no abnormal findings

2000, m

11, 12, 13, 14, 15

 

2000, f

16, 17, 18, 19, 20

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
No local or systemic test substance related effects were noted from clinical observations or post-mortem examination at a dose of 2000 mg test substance per kg body weight. The LD50,dermal of "3-hydroxy-2-(hydroxymethyl)-2-methylpropionaldehyde" is higher than 2000 mg/kg body weight in rats.
Executive summary:

The aim of the study was to investigate acute toxic effects of the test substance after a single dermal administration to rats.

Methods

Methods and investigations were performed in conformance with the OECD-Guideline 402, 1987 and theCouncil Regulation (EC) No 440/2008, Method B.3.

Administration of the test substance

"3-hydroxy-2-(hydroxymethyl)-2-methylpropionaldehyde"was administered once topically on an area of approximately 6.5 cm x 8 cm on the dorsal thoracicregion of 5 male and 5 female Sprague Dawley rats.

The dose was 2000 mg per kg body weight.

A cellulose patch with the calculated amount of the test substance on the surface and soaked with deionised water to get optimal contact with the skin, was applied to the test site and held in place by fixing marginally with non irritating tape.

The test site was covered by a semi-occlusive dressing.

The duration of the exposure was 24 hours.

Investigations

·      Body weights: before the administration, 7 and 14 days after the administration (p.a.).

·      Clinical observations: at least once per day.

·      Necropsy: All animals were sacrificed and necropsied 14 days p.a.

Results

dose
(mg/kg)

sex

No. of animals

prominent findings

exposed

affected

deceased

in life

post mortem

 

 

 

 

 

systemic

local

 

2000

male

5

1

0

none

chromodacryorrhoea

none

2000

female

5

0

0

none

none

none

Staining of the skin which is attributed to the staining property of the test substance was observed in all animals.

 

presence of clinical signs in 1/10 animals

from 4 h to 6 h p.a.

full recovery of the animal

yes

body weights

all animals gained weight in both weeks p.a.

sex differences

no

 

 

findings in life and post-mortem indicate

no toxic effects present

 

 

LD50, dermal

> 2000 mg/kg body weight

 

 

Conclusion

 

No local or systemic toxic effects related to administration of the test substance were noted from clinical observations or post-mortem-examination at a dose of 2000 mg of the test substance per kg body weight.

No mortality occurred.

 

No classification of"3-hydroxy-2-(hydroxymethyl)-2-methylpropionaldehyde"is therefore derived from the results of this study according to the Directive 2001/59/EC.