Dialuminum tetramagnesium carbonate dodecahydroxide

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March 1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was performed similar to OECD 405 guideline but without GLP. Limited information on test material and environmental conditions.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Principles of method if other than guideline:

The extent of DHT-4A ocular mucous membrane-stimulating effects were investigated in rabbits using the Draize's rating scale.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Aluminium magnesium carbonate hydroxide

EC Number:

943-434-4

Cas Number:

11097-59-9

Molecular formula:

[Al2Mg4(OH)12] CO3

IUPAC Name:

Aluminium magnesium carbonate hydroxide

Details on test material:

Chemical Formula: Mg4.5AL2(OH)13CO3 3.5H2O
Chemical nomenclature: Hydrotalcite DHT-4A

Test animals / tissue source

Species:

rabbit

Strain:

other: male Japanese rabbits (Yugengaisha Ichikaway)

Details on test animals or tissues and environmental conditions:

Healthy white Japanese rabbits weighing approximately 3kg (Yugengaisha I chikawaya ) were used for this study .
All were male, totaling 9. Solid food manufactured by Clea Japan Inc. (CR-l) and normal drinking water in a bottle were taken ad libitum.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

100 mg of undiluted test drug was dropped into the everted lower lid;
upper and lower lids were separated after light contact.

Duration of treatment / exposure:

The rabbits were divided into the 3 whose eyes were not washed after treatment, the 3 those whose eyes were washed with 20ml of mild warm water 2 seconds after treatment, and the 3 those whose eyes were washed with 20 ml of tepid water 4 seconds after treatment.

Observation period (in vivo):

All rabbits were observed 1, 2, 3, 4 and 7 days later and evaluated according to rating criteria.

Number of animals or in vitro replicates:

9

Details on study design:

The experiment was carried out according to the following procedure .
(a ) Nine white male Japanese rabbits (weighing approximately 3kg ) , adjudged normal following a cornea test with fluorescein paper (Haag-streit ag
liebefed-dern Switzerland) were used .
(b) The test drug was dropped into the right eye, the left eye being left untreated for comparison. 100 mg of undiluted test drug was dropped into the everted lower lid; upper and lower lids were separated after light contact.
(c) The rabbits were divided into the 3 whose eyes were not washed after treatment, the 3 those whose eyes were washed with 20ml of mild warm
water 2 seconds after treatment,and the 3 those whose eyes were washed with 20 mL of tepid water 4 seconds after treatment.
(d) all the rabbits were observed 1,2,,3,4, and 7 days later and evaluated according to rating criteria.
(e) after 7- days of observation the animals were killed for autopsy; the upper and lower eyelids, nicititating membranes eyeballs and optic nerves were removed and preserved in formalin fixative.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

animal #1, #2 and #3

Time point:

other: overall 24, 48 and 72 h

Score:

0

Max. score:

4

Remarks on result:

other: eyes not washed

Results 2

Irritation parameter:

iris score

Basis:

mean

Remarks:

animal #1, #2 and #3

Time point:

other: overall 24, 48 and 72 h

Score:

0

Max. score:

2

Remarks on result:

other: eyes not washed

Results 3

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

mean

Remarks:

animal #1 and #3

Time point:

other: overall 24, 48 and 72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Remarks on result:

other: eyes not washed

Results 4

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #2

Time point:

other: overall 24, 48 and 72 h

Score:

0

Max. score:

3

Remarks on result:

other: eyes not washed

Results 5

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

animal #1 and #2

Time point:

other: overall 24, 48 and 72 h

Score:

0

Max. score:

4

Remarks on result:

other: eyes not washed

Results 6

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

other: overall 24, 48 and 72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 hours

Remarks on result:

other: eyes not washed

Irritant / corrosive response data:

In ocular response to DHT-4A undiluted, chief symptoms were conjunctival changes , whereas there were no changes in the cornea or iris.

1. Rabbits whose eyes were not washed
On the first day of eye - dropping, accelerated congestion of the conjunctiva was noted in two of the three rabbits,
while exaggerated conjunctival edema and excess discharge were observed in the other .
However, on the second day of eye-dropping , conjunctival congestion , edema and discharge began to disappear .

2. Rabbits whose eyes were washed 2 seconds after treatment.
On the first day of eye-dropping, excessive discharge was observed in two out of the three.
On the second day of eye-dropping , such disc harge began to cease.

3 . Rabbits whose eyes were washed 4 seconds after treatment .
On the first day of eye-dropping, accelerated conjunctival congestion was noticed in two of the three rabbits, but it disappeared on the second day.

Other effects:

In all the animals killed at the end of the test period , there were no significant changes in the upper or lower lids ,
nictitating membranes, eye balls , optic nerves or other organs.

Any other information on results incl. tables

In ocular response to DHT-4A undiluted, chief symptoms were conjunctival changes , whereas there were no changes in the cornea or iris.

1. Rabbits whose e yes were not washed

On the first day of eye - dropping, accelerated congestion of the conjunctiva was noted in two of the three rabbits,

while exaggerated conjunctival edema and excess discharge were observed in the other .

However, on the second day of eye-dropping , conjunctival congestion , edema and discharge began to disappear .

2. Rabbits whose eyes were washed 2 seconds after treatment.

On the first day of eye-dropping, excessive discharge was observed in two out of the three.

On the second day of eye-dropping , such disc harge began to cease.

3 . Rabbits whose eyes were washed 4 seconds after treatment .

On the first day of eye-dropping, accelerated conjunctival congestion was noticed in two of the three rabbits, but it disappeared on the second day.

Applicant's summary and conclusion

Interpretation of results:

slightly irritating

Remarks:

Migrated information The very slight effects were fully reversible 48 hours after application. Criteria used for interpretation of results: EU

Conclusions:

This study of the primary stimulating effect of DHT- 4A on the ocular mucous membrane of the rabbit performed similar to OECD 405 guideline, indicated that DHT-4A showed very slight conjunctivae in 2 animals and very slight chemosis in one animal. The effects were fully reversible 48 hours after application.

Executive summary:

This study of the primary stimulating effect of DHT- 4A on the ocular mucous membrane of the rabbit performed similar to OECD 405 guideline.

DHT-4A showed very slight conjunctivae in 2 animals and very slight chemosis in one animal. The effects were fully reversible 48 hours after application. Based on the results, DHT-4A does not have to be classified for eye irritation according to Regulation (EC) No 1272/2008.

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