Uronium hydrogen sulphate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

end on 30-MAY-2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Uronium hydrogen sulphate

EC Number:

244-343-6

EC Name:

Uronium hydrogen sulphate

Cas Number:

21351-39-3

Molecular formula:

CH4N2O.H2O4S

IUPAC Name:

amino(hydroxy)methaniminium hydrogen sulfate

Details on test material:

- Name of test material (as cited in study report): Lower-7/Acid Flow/Enquik
- Substance type: monoconstituent substance
- Physical state: liquid
- Stability under test conditions: data not available
- Storage condition of test material: room temperature in darkness

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Granja San Bernardo, SL (Tulebras, Navarra)
- Age at study initiation: approximate age of 11-12 weeks
- Weight at study initiation: 2.8-3.2 kg
- Housing: the rabbits were housed individually in stainless steel cages (52.0 x 58.0 x 43.0 cm) placed on shelves and equipped with slatted floors.
- Diet: free access to a standard diet for rabbits Panlab 112
- Water: ad libitum
- Acclimation period: a minimum period of seven days

ENVIRONMENTAL CONDITIONS
- Temperature: 20-25 ºC
- Humidity: 30-65%
- Air changes: data not avaiable
- Photoperiod: 12 hours of light (7:00 to 19:00) and 12 hours of darkness every 24 hours

IN-LIFE DATES: data not available

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied: 0.5 mL
- Concentration: undiluted

Duration of treatment / exposure:

4 hours

Observation period:

14 days

Number of animals:

3 animals

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm
- % coverage: data not available
- Type of wrap if used: semi-occlusive patches used were fixed with a band or adhesive micro-porous hypoallergenic

REMOVAL OF TEST SUBSTANCE
- Washing: yes
- Time after start of exposure: after exposure with distilled water

SCORING SYSTEM: according to OECD guideline

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: mean value (24, 48, 72h)

Score:

1.22

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

other: mean value (24, 48, 72h)

Score:

0.22

Max. score:

2

Reversibility:

fully reversible within: 48 hours

Irritant / corrosive response data:

It initially used a single animal (no. 1995), sequentially applying three dressings. The first dressing was removed after three minutes. After no serious skin reaction, it was applied a second dressing, which was retired after 1 hour. There was no serious skin reaction to either remove the second pack, so it was applied a third, which was removed at 4 hours d exposure.
At 60 minutes, at 24, 48 and 72 hours, 7 and 14 days after removal of patches exposed for 3 minutes and 1 hour respectively, there were no injuries in the area administered.
At 60 minutes after removing the patch exposed for four hours, it was observed well-defined erythema (grade 2) with slight edema (grade 2). At 24 hours after removal of the patch, there was very slight erythema (grade 1) accompanied by very slight edema (grade 1). At 48 and 72 hours after removal of the patch exposed for four hours the edema had complete remission, although there was again well-defined erythema (grade 2), which decreased to very slight edema (grade 1) during the observation at 7 days after removal of the patch. No skin changes were observed at 14 days after removing the patch in this animal, except slight scaling.
Subsequently it was applied to two animals (no. 2004 and 2005) a dressing with the test, it was was removed after 4 hours of exposure.
At 60 minutes after removing the patch, in one of these two animals (no. 2004) was recorded very slight erythema (grade 1) with very slight edema (grade 1). At 24, 48 and 72 hours in this animal was observed very slight erythema (grade 1). At 7 and 14 days after removing the patch, there were no skin lesions in this animal, although there was slight scaling during the observation at 7 days.
At 60 minutes after removing the patch, in the remaining animal (No. 2005) showed well defined erythema (grade 2) with slight edema (grade 2). At 24, 48 and 72 hours in this animal was recorded very slight erythema (grade 1), with very slight edema (grade 1) only in the reading performed at 24 hours. At 7 days after removing the patch, there were no skin lesions in this animal.
Mean ratings of erythema and edema at 24, 48 and 72 hours of the three animals after a 4-hour exposure were 1.22 (erythema) and 0.22 (edema).

Other effects:

The behavior and physical condition of the rabbits, and the evolution of body weight was normal during the study.

Any other information on results incl. tables

Table 1: Irritant/corrosive response data for each animal at each observation time up to removal of each animal from the test

Score at time point / Reversibility	Erythema	Edema
	Max. score: 4	Max. score: 2
60 min	2 / 1 / 2	2 / 1 / 2
24 h	1 / 1 / 1	1 / 0 / 1
48 h	2 / 1 / 1	0 / 0 / 0
72 h	2 / 1 / 1	0 / 0 / 0
Average 24h, 48h, 72h	1.7 / 1 / 1	0.3 / 0 / 0.3
7 days	1 / 0 / 0	0 / 0 / 0
14 days	0 / 0 / -	0 / 0 / -
Reversibility*)	yes	yes
Average time for reversion	14 days	48 hours

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

Urea sulphate is not considered as irritant to the skin.

Executive summary:

In a primary dermal irritation study (OECD 404, GLP), young adult New Zealand White rabbits (3 animals) were dermally exposed to 0.5 mL of undiluted Lower-7/Acid Flow / Enquik (Uronium hydrogen sulphate) for 4 hours under semi-occlusive conditions. Animals then were observed for 14 days. Irritation was scored by the method cited in OECD guideline.

 

Mean ratings of erythema and edema at 24, 48 and 72 hours of the three animals after a 4-hour exposure were 1.22 (erythema) and 0.22 (edema).

 

In this study, Lower-7/Acid Flow / Enquik (uronium hydrogen sulphate) is not a dermal irritant. Classification is not required according to EU legislation (DSD or CLP).