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Toxicological information

Skin irritation / corrosion

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Administrative data

Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Study initiation: 25 January 2012 Final report: 09 March 2012
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
comparable to guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2012
Report Date:
2012

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
GLP compliance:
yes (incl. certificate)
Remarks:
Korea

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid
Specific details on test material used for the study:
Chemical Name: 1,3,2-Dioxathiolane, 2,2-dioxide
Product Name : ESA
Received date : 22 November 2011
Appearance : lemon-yellow solid
Purity : 99.1 %
Storage condition : Room temperature or refrigerator (2 - 8 ºC)
Stability: stable
Supplier: LG Chemicals Co., Ltd.

Test animals

Species:
rabbit
Strain:
New Zealand White
Details on test animals and environmental conditions:
Species and strain: Specific Pathogen Free (SPF) New Zealand White (NZW) rabbits.
Supplier: ORIENT BIO INC.(Address; 143-1, Sangdaewondong, Jungwon-gu, Seongnam-si, Gyeonggi-do, Korea)
Producer: Laboratory animals center, Cheonan yonam college (Address : San 3-1, Suhyang-ri, Seonghwan-eup, Seobuk-gu, Cheonan-si, Chungcheongnam-do, Korea)
Species selection Justification: The NZW rabbits used in this study are widely used in general dermal irritation experiments for toxicity testing. In addition, sufficient raw data associated with this species has been accumulated and is available for interpretation and evaluation of study results.
Date of the acquisition: 30 January 2012
Number of received animals: 5 male animals
Body weights and ages on arrival: 1783.78 - 1894.90 g, 10 weeks old
Quarantine and acclimation: On arrival, animals were examined based on the certificate provided by the supplier. The period of acclimation was 7 days. Only healthy animals was used for the test after observing general symptoms in the acclimated period.
Body weights and ages at administration: 2015.96 g, 11 weeks old
Number of animals administered test substance: 1 animal (male)
Grouping: After selection of animal weighed more than 2.0 kg, the dorsal skin of rabbits was shaved using an electric clipper to expose normal naked skin, within 24
hours, before administration. Attention was given not to make a wound. Rabbits with healthy skin were chosen randomly.
Identification of animals: Each animal was identified for this study by a unique number marked indelibly on the inner surface of the ear and written on the cage label. Information about animals and study was also posted on the door of the animals room.
Disposal of remaining animals: All remaining animals were euthanized by CO2 over-inhalation on experimental completion day.

Animal Care Facility
Range of temperature and humidity during test work: Temperature of 22.2±0.7 ºC, Relative humidity of 44.3±2.4 %
Ventilation frequency: 10-15 air changes /hr.
Lighting cycle: 12 hrs lighting duration (lighting on at 8 a.m. ~ lighting off at 8 p.m.)
Lighting intensity: 288 Lux.
Ambient noise level: 53.9 dB
Ammonia concentration : less than 5 ppm
Housing: All animals were individually housed in stainless steel cages (380W×500D×330H mm) during the test period.
Feed: Laboratory rabbit diet, Agribrands Purina Korea Inc. (Address: 8th Floor Hanlimwon Building, 7-1, Gu Mi-Dong, BunDang-Gu, Sung Nam-Shi, Kyong Gi-Do, Korea)
Supplied ad libitum. Analysis carried out by supplier. No significant factors to affect the experimental results were found.
Water: Incheon, Korea municipal tap water purified by reverse osmosis filtering system. Supplied ad libitum. Analysis was performed by national certificated inspection organization. No significant factors to affect the experimental results were found.

Test system

Type of coverage:
occlusive
Preparation of test site:
shaved
Vehicle:
unchanged (no vehicle)
Controls:
yes, concurrent negative control
Amount / concentration applied:
0.5 g of test substance
Duration of treatment / exposure:
3 minutes, 1 hour and 4 hours
Observation period:
1 and 24 hours
Number of animals:
one male
Details on study design:
Application method
Preparation of test site:
Shaved area was divided into left and right sections. 6 cm2 areas were marked in each section. The left sections was used for application of test substance, and the right sections was used for control.
Application method and volume:
Before the administration, the dorsal back side of one rabbit were clipped free of fur. 0.5 g of test substance was applied onto left treated section of about 6 cm2 once. To ensure sufficient good skin contact, gauze patch moistened with the smallest amount of Physiological saline (87J6P61) covered on treated section. The entire trunk of the animals was wrapped with non-irritant adhesive tape (TegadermTM 1626W, 3M Health Care). Separately, 0.5 mL of physiological saline (87J6P61, DAIHAN Pharm Co. Ltd) was applied for the control in the same way as the test substance.
Frequency of administration & period of administration:
The test substance was applied once at dermal. In the initial test, the test substance was applied by patch in one rabbit. First patch was removed after 3 minutes and no skin reaction was observed. Second patch was applied at a different site and removed after 1 hour and some irritaion was observed. Third patch was applied and removed after 4 hours at another site and the corrosion was observed. Therefore, the confirmatory test was not performed.
After application, the treated sections were washed gently with the physiological saline (087J6P61, DAIHAN Pharm Co. Ltd) to remove the residual of test substance.
Selection of dosage:
The volume of test substance was determined 0.5 g in accordance with National Institute of Environmental Research Notification No.2010-29 "Designation of chemical hazard test research organization"(16 August 2010).

Observations
Clinical signs:
All animals were observed daily from on day of test substance application until experiment termination day for appearance, food and water consumption, clinical signs and survival.
Body weight:
Individual body weight was measured before test substance application, and at 24 hours after application.
Observation of application site:
Test sites were evaluated for corrosion and irritation (erythema, eschar and edema etc.) at 1 and 24 hours after patch removal.
Evaluation of dermal irritation/corrosion
The skin responses were scored according to 'Grading of skin reaction by National Institute of Environmental Research Notification No.2010-29 "Designation of chemical hazard test research organization"(16 August 2010). The corrosive responses were evaluated according to 'Skin and eye irritation assessment guidelines' by National Institute of Environmental Research Notification Guidelines (12 November 2008).
Histopathological examination:
The animal in the initial test was euthanized by CO2 over-inhalation at 24 hours after patch removal. The skins were collected in sites exposed to control and test substance. The skins were fixed in a 10% formalin solution containing neutral phosphate-buffered saline and stained with hematoxylin and eosin and examined under light microscopy to clarify skin corrosion.

Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
erythema score
Basis:
animal #1
Remarks:
4 hr exposure
Time point:
24 h
Score:
4
Max. score:
4
Reversibility:
other: not expected to be reversible
Remarks on result:
other: animal humanely killed
Irritation parameter:
edema score
Basis:
animal #1
Remarks:
4 hr exposure
Time point:
24 h
Score:
4
Max. score:
4
Reversibility:
other: not expected to be reversible
Remarks on result:
other: animal humanely killed
Irritation parameter:
erythema score
Basis:
animal #1
Time point:
48 h
Remarks on result:
other: not applicable
Irritation parameter:
erythema score
Basis:
animal #1
Time point:
72 h
Remarks on result:
other: not applicable
Irritation parameter:
edema score
Basis:
animal #1
Time point:
48 h
Remarks on result:
other: not applicable
Irritation parameter:
edema score
Basis:
animal #1
Time point:
72 h
Remarks on result:
other: not applicable
Irritant / corrosive response data:
Observation of application site
Erythema and eschar formation:
Moderate erythema was observed at 1 hour after exposure of test substance. Severe erythema and partially skin necrosis were observed at 4 hour after exposure of test substance.
Severe erythema and partially skin necrosis were observed at 1 and 24 hours after patch removal.
In the negative control, no signs were observed on the skin during the experimental period.
Edema:
No edema was not observed at 3 minutes and 1 hour after exposure of test substance. Severe edema was observed at 4 hour after exposure of test substance.
Severe edema was observed at 1 and 24 hours after patch removal. In the negative control, no signs were observed on the skin during the experimental period.

Histopathological examination:
Broadly diffuse necrosis and swelling in epidermis and dermis were observed at test site. Also, desquamation of stratum corneum in epidermis and congestion in dermis layer were observed.

Evaluation of corrosion
Based on the results of skin response at 1 and 24 hours after patch removal and histopathological examination, the test substance, ESA is considered a corrosive material.
Other effects:
Mortalities and clinical signs:
In the initial test, no significant clinical signs and mortalities was observed.
Body weight changes:
In body weight changes, temporary decrease was observed after test substance application.

Applicant's summary and conclusion

Interpretation of results:
Category 1 (corrosive) based on GHS criteria
Remarks:
In the study report only initial observations were included for 3 minute and 1 hour treatment. It is not clear if further observations were made for these treatment times. Therefore, a sub-category cannot be assigned.
Conclusions:
This study was performed to evaluate first irritation and corrosion of ESA in one male New Zealand White Rabbits. 0.5 g of the test substance was applied to the skin of NZW rabbits for 4 hours. Parameters (mortalities, clinical signs, body weight changes and skin response) were measured.
No clinical sign and mortality was observed relating to test substance treatment. Decrease in body weight at the next day of application was observed, but the sign was considerd temporary by the stress of treatment.
In the initial test, erythema was observed at 1 hour after exposure of test substance. Erythema, edema and partially necrosis were observed at 4 hours after exposure of test substance.
Severe erythema and edema with skin necrosis were observed at 1 and 24 hours after patch removal. The animal was humanely killed without additional observation because the effects of test substance was not expected to be recovered. In the histopathological examination to clarify corrosion, broadly diffuse necrosis, swelling in epidermis and dermis, desquamation of stratum corneum in epidermis and congestion in dermis layer were observed. In the negative control, no signs were observed during the experimental period.
On the basis of the above results, ESA on skin application of New Zealand White rabbit is not related to clinical signs, mortality and body weights and is considered a corrosive material that causes irreversible response.
Executive summary:

This study was performed to evaluate irritation potential of ESA. In one male New Zealand White Rabbit, the test substance of 0.5 g was applied to the dorsal skin of NZW rabbits for 4 hours. Parameters measured were mortalities, clinical signs and body weight changes after test substance application. The response of each local irritation was evaluated by National Institute of Environmental Research Notification No. 2010-29. The

skin reaction was assessed in comparison with application site for test substance and intact site for the control. The finding results were as follows :

1) No clinical signs and mortalities related to test substance treatment were observed.

2) No significant body weight changes related to test substance treatment was observed.

3) In the initial test, erythema, eschar, edema and necrotic lesion of skin were observed at 1 and 24 hours after patch removal. The test was terminated because the effect of test substance was not expected to be recovered. In the negative control, no signs were observed on the skin during the experimental period.

On the basis of the above results, ESA on skin application of New Zealand White rabbit is considered a corrosive material that causes irreversible response.