Magnesium metaborate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016-08-23 - 2016-08-26

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

The contract to conduct an in vivo skin irritation study was signed before the entry into force of the amendments (Commission Regulation (EU) 2016/863 from 31 May 2016) to Annexes VII and VIII of the REACH Regulation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Certificate issued by "The Department of Health and of the Government of the United Kingdom" (2016-10-28).

Test material

Test material information

1

Reference substance name:

Magnesium metaborate

EC Number:

237-235-5

EC Name:

Magnesium metaborate

Cas Number:

13703-82-7

Molecular formula:

BHO2.1/2Mg

IUPAC Name:

magnesium metaborate

Test material form:

liquid

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Envigo RMS (UK) Limited, Leicestershire, UK
- Age at study initiation: 12 to 52 weeks
- Weight at study initiation: 3.5 or 3.66 kg
- Housing: Individually housed in suspended cages. The animals were provided with environmental enrichment items which were considered not to contain any contaminant of a level that might have affected the purpose of integrity of the study.
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 to 23 °C
- Humidity (%): 30 - 70 %
- Air changes (per hr): at least 15 per hr
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Remarks:

with veterinary clippers

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL
- Concentration: used as provided

Duration of treatment / exposure:

4 hours

Observation period:

72 hours

Number of animals:

Two females

Details on study design:

TEST SITE
- Area of exposure: 2.5 cm x 2.5 cm
- Type of wrap if used: cotton gauze patch secured with surgical adhesive tape. The trunk of each rabbit was wrapped in elasticated corset to prevent the animals interfering with the patches.

REMOVAL OF TEST SUBSTANCE
- Washing: Residual test item removed by gentle swabbing with cotton wool soaked in 74% industrial methylated spirits.
- Time after start of exposure: 4 hours

OBSERVATION TIME POINTS
Immediately following removal of the patches and approximately 1, 24, 48 and 72 hours later. Test sites were examined for evidence of primary irritation and scored. Any other skin reaction and clinical signs of toxicity, if present, were also recorded.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

0.3

Reversibility:

fully reversible within: 24 hours

Results 2

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Reversibility:

fully reversible within: 24 hours

Results 3

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.3

Reversibility:

fully reversible within: 24 hours

Irritant / corrosive response data:

Very slight erythema was noted for both treated skin sites at the 24 hour observation. Very slight edema was noted at one treated skin site at the 24 hour observation.

Other effects:

There were no deaths during the study.
Animals showed expected gain in body weight during the study.

Any other information on results incl. tables

Table 1: Individual Skin Reactions.

Skin Reaction	Observation Time (following patch removal)	Individual Scores		Mean 24, 48 and 72 Hour Scores
		Rabbit Number and Sex
		75517 Female	75518 Female
Erythema/ Eschar Formation	Immediately	0	0	0.3
	1 Hour	0	0
	24 Hours	1	1
	48 Hours	0	0
	72 Hours	0	0
Edema Formation	Immediately	0	0	0.0 and 0.3, respectively
	1 Hour	0	0
	24 Hours	0	1
	48 Hours	0	0
	72 Hours	0	0

Applicant's summary and conclusion

Interpretation of results:

other: EU GHS (CLP) criteria not met

Remarks:

not irritating

Conclusions:

The test item produced individual mean scores of 0.3 for erythema (both animals) and 0.0 and 0.3 respectively for edema.

Executive summary:

The in vivo study was performed to assess the irritancy of the test item to the skin of New Zealand White rabbit in accordance with OECD Guideline 404 and EU Method B.4 and in compliance with GLP criteria.

A suitable test site was selected at the back of each rabbit. A quantity of 0.5 mL of the test item was applied directly to the skin under a 2.5 cm x 2.5 cm cotton gauze patch. The patch was secured with a strip of surgical adhesive tape. Residual test item removed by gentle swabbing with cotton wool soaked in 74% industrial methylated spirits after a 4 hour exposure of the test item. Observations were made immediatly following removal of the patches and approximately 1, 24, 48 and 72 hours later. The single 4 -hour, semi occluded application of the test item to the intact skin of two rabbits produced very slight erythema at both treated skin sites at the 24 hour observation. Very slight edema was noted at one treated skin site at the 24 hour observation. Mean scores following grating at 24, 48 and 72 hours following patch removal were calculated for erythema and edema. Calculation of the Primary Irritation Index and Grading of Irritancy Potential Using the Daize Scheme. If irreversible alterations of the dermal tissue is noted in any rabbit, as judged by the Study Director, which include ulceration and clear necrosis or signs of scar tissue, the test item is considered to be corrosive to rabbit skin. Grading according to Draize may, therefore, not be applicable.

The test item produced individual mean scores of 0.3 for erythema (both animals) and 0.0 and 0.3 respectively for edema.