Reaction products of monoethanolamine and boric acid (1:3)

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Justification for type of information:

A read-across approach is applied between Reaction products of monoethanolamine and boric acid (1:1) and Reaction products of monoethanolamine and boric acid (1:3) for the human health endpoints due to the structural similarity of the two reaction products (Scenario 6 in ECHA’s RAAF document), both resulting from the same starting materials (only the ratio is different), and through the same manufacturing process.
Commercial MEA Polyborate products are commonly formulated at either 1:1 or 1:3 mole ratios of MEA to boric acid, or sometimes at ratios in between. All compositions in this range contain equilibrium mixtures of the exact same chemical species, but with somewhat different population distributions.
The existing physico-chemical, toxicological, environmental fate and ecotoxicological data already showed good correlation with no significant differences between the two ratios.

The results of the newly commissioned, additional anchoring studies (water solubility, vapour pressure and octanol-water coefficient, Salmonella typhimurium reverse mutation assay and in the Escherichia coli reverse mutation assays, acute toxicity studies via dermal route and oral route) showed good correlation between Reaction products of monoethanolamine and boric acid (1:1) and Reaction products of monoethanolamine and boric acid (1:3), and therefore further supported our category hypothesis.

Based on the lack of dermal irritation responses in the rabbit from dermal application of MEA Polyborate 1:3, no GHS classification for skin irritation is proposed for both 1:1 and 1:3 ratios. Three 0.5 ml doses of undiluted MEA Polyborate 1:3 were applied to the dorsum of a single New Zealand White rabbit. Each test site was covered by a gauze patch, which was removed after exposure periods of 3 minutes, one hour and four hours. Dermal reactions were assessed immediately after removal of each dressing. All dermal sites were re-assessed 24, 48 and 72 hours after removal of the last dressing. No dermal irritation was observed at any of the three sites or time periods (Covance 1998b). In addition, in vitro and in vivo eye irritation studies are available on both ratios, and show correlation with only slight difference, i.e. MEA Polyborate 1:1 is not irritating in an in vivo eye irritation study, whilst MEA Polyborate 1:3 is moderately irritating.
On this basis MEA Polyborate 1:1 is considered not to be an irritant to skin.
Category: MEA Polyborates

Materials and methods

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

1

Reference substance name:

3-hydroxypropan-1-aminium; tetrahydroxyspiro[5.5]pentaboroxan-6-uide

EC Number:

701-024-0

Cas Number:

26038-87-9

Molecular formula:

C2H7NO.xBH3O3

IUPAC Name:

3-hydroxypropan-1-aminium; tetrahydroxyspiro[5.5]pentaboroxan-6-uide

Test material form:

liquid

Remarks:

clear colourless

Details on test material:

UVCB
At room temperature protected from light
31 March 2018 (expiry date)

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Remarks:

mean

Time point:

24/48/72 h

Score:

0

Reversibility:

no data

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Remarks:

mean

Time point:

24/48/72 h

Score:

0

Reversibility:

not specified

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Remarks:

mean

Time point:

24/48/72 h

Score:

0.3

Reversibility:

not specified

Results 4

Irritation parameter:

edema score

Basis:

animal #1

Remarks:

mean

Time point:

24/48/72 h

Score:

0

Reversibility:

no data

Results 5

Irritation parameter:

edema score

Basis:

animal #2

Remarks:

mean

Time point:

24/48/72 h

Score:

0

Reversibility:

not specified

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Remarks:

mean

Time point:

24/48/72 h

Score:

0

Reversibility:

not specified

Irritant / corrosive response data:

1 hour observation
Rabbit number Erythema Oedema Comments
660 0 0 None
677 0 0 None
678 1 0 None
24 hour observation
Rabbit number Erythema Oedema Comments
660 0 0 None
677 0 0 None
678 1 0 None
48 hour observation
Rabbit number Erythema Oedema Comments
660 0 0 None
677 0 0 None
678 0 0 None
72 hour observation
Rabbit number Erythema Oedema Comments
660 0 0 None
677 0 0 None
678 0 0 None

Other effects:

none

Any other information on results incl. tables

Mean scores for erythema and oedema (calculated from the values recorded at the 24,48 and 72 hour readings) were used.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

According to the criteria described in EEC Commission Directive 91/325/EEC of 1st March 1991, MEA Polyborate 1:1 is not classified for skin irritation/corrosion. Based on the justification in the field ' Justification for type of information', this results is applicable for MEA Polyborate 1:3.

Executive summary:

The purpose of this study was to assess the degree of irritation produced by the test article when applied to the skin of the albino rabbit. The procedures e used were in accordance with EEC Annex V guidelines.

A 0.5 aliquot of the test article was applied over a previously clipped area of about 6 sq cm of the dorsal skin of each of 3 albino rabbits. The test article was held in contact with the skin, under a semi-occlusive patch assembly, for a 4 hour period. The patches were then removed and skin reaction assessed after one, 24, 48 and 72 hours.

The treated site on 2 of the 3 rabbits remained free from apparent irritation throughout the 72 hour observation period. A barely perceptable erythema was noted at the treated site on the third animal one and 24 hours after patch removal but was no longer apparent at the 48 and 72 hour examinations.

The test article did not produce significant irritation in any animal.

According to the criteria described in EEC Commission Directive 91/325/EEC of 1st March 1991, MEA Polyborate 1:1 is not classified for skin irritation/corrosion. Based on the justification in the field ' Justification for type of information', this results is applicable for MEA Polyborate 1:3.