[4-[α-[4-(dimethylamino)phenyl]benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium acetate

Endpoint summary

Description of key information

Skin irritation / corrosion = not irritant

Eye irritation = eye damage

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No GLP, aged study, poor detail on test conditions Read across from a similar substance which has the same main component and with a different counter ion that doesn't influence the characteristics related to the specific end-point

Reason / purpose for cross-reference:

reference to same study

Principles of method if other than guideline:

For skin application a site of 35 cm^2 was clipped 3 h before administration and the site covered by four-ply gauze and an elastic bandage.

GLP compliance:

no

Species:

other: rat and guinea pig

Strain:

Wistar

Details on test animals or test system and environmental conditions:

TEST ANIMALS
RATS
- Strain: Wistar rats, Mol: WIST (SPF)
- Weight at study initiation: 170-250 g
- Source: from Molllegard Breeding Centre (L1. Skensved, Denmark)

GUINEA PIG
- Strain: Ssc, AL
- Source: Statens Serumininstitut, (Copenhagen, Denmark)
- Weight at study initiation: 300 g

All were given food and water freely except 16 h before gavage.
For rats
- Temperature: kept at 22 ± 1°C
- Humidity: 60 ± 10%
- Light: from 21.00 to 09.00 with air changes eight times/h.

Type of coverage:

occlusive

Preparation of test site:

not specified

Vehicle:

water

Controls:

yes, concurrent no treatment

Amount / concentration applied:

TEST MATERIAL
- Vehicle: aqueous solution
- Concentration: MGH at 20%

Duration of treatment / exposure:

single dose application

Observation period:

1, 2, 3, and 5 h after dosing and each day for 14 days

Number of animals:

Groups of five animals of either sex

Details on study design:

For skin application a site of 35 cm^2 was clipped 3 h before administration and the site covered by four-ply gauze and an elastic bandage (Acrylastic, Beiersdorf AG, FRG)

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Remarks on result:

other: See report below

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Remarks on result:

other: See comments

No signs of systemic toxicity were observed after occlusive dermal application of 2000 mg/kg. As a 20% suspension of Malachite Green did not produce visible erythema or oedema on either rats or guinea pigs; authors hadn't deemed it meaningful doing a rabbit skin irritation study. Similarly, within the conditions of the guinea pig maximisation test no effects could be seen on controls or treated animals.

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

No signs of systemic toxicity were observed: not visible erythema or oedema on either rats or guinea pigs were observed.

Executive summary:

Rats ang guinea pig were tested for dermal acute toxicity. For skin application a site of 35 cm^2 was clipped 3 h before administration and the site covered by four-ply gauze and an elastic bandage.

No signs of systemic toxicity were observed after occlusive dermal application of 2000 mg/kg. As a 20% suspension of Malachite Green did not produce visible erythema or oedema on either rats or guinea pigs; authors hadn't deemed it meaningful doing a rabbit skin irritation study. Similarly, within the conditions of the guinea pig maximisation test no effects could be seen on controls or treated animals.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well described; no GLP Read across from a similar substance which has the same main component and with a different counter ion that doesn't influence the characteristics related to the specific end-point

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

yes

Remarks:

Observation period of 8 days; no observation at 14, and 21 days in order to determine the status of the lesions, and their reversibility or irreversibility

GLP compliance:

no

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Hagemann GmbH & C0
- Weight at study initiation: 2.4 kg
- Diet: Mummel Z ad libitum
- Water: ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature: 16 - 18°C
- Humidity: 40%
- Photoperiod: 12 Hrs cycle dark/light

Vehicle:

water

Controls:

not specified

Amount / concentration applied:

TEST MATERIAL
- Concentration 100 µL

Number of animals or in vitro replicates:

3 male rabbit

Details on study design:

SCORING SYSTEM:
OECD 405

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

ca. 3

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

ca. 3

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

ca. 3

Max. score:

4

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

ca. 2

Max. score:

2

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

ca. 2

Max. score:

2

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

ca. 2

Max. score:

2

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

ca. 12

Max. score:

20

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

ca. 12.6

Max. score:

20

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

ca. 12.6

Max. score:

20

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Reversibility:

not reversible

Remarks on result:

other: See comments

Irritant / corrosive response data:

cornea: pearl red. No visible details of iris. size of the pupil slightly different

Interpretation of results:

other: CLP: Eye dam. 1

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

The substance is classified as high irritant. No regression of tissue lesions before 8 day.

Executive summary:

Number of 3 Newzeland white rabbit as chosen to test Malachite Green for eye irritation/corrosion following OECD guideline 405.

The substance is classified as high irritant. No regression of tissue lesions before 8 day. Nevertheless no data available on reversibility or irreversibility of the substance, because no observation were conducted at 14, and 21 days in order to determine the status of the lesions.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irreversible damage)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation/Skin Corrosion

Clemmensen et al. (1984) tested the skin irritation of Malachite Green (MG) oxalate. A 20 % (200 mg/ml) suspension did not produce visible erythema or oedema on either rats or guinea pigs, therefore rabbit skin irritation study was not performed.

In the Dystar (1982) study, conducted following OECD guidelines, after the sample administrations the skin of the rabbit resulted coloured in green and oedema was not easily identifiable; slight dehydration of the skin and no complete repair within 8 days were noted, nevertheless it is reasonable to assume that the effect is reversible in 14 days. Considering that dryness is not clearly an irritation effect and based on the Clemmensen study, the substance can be considered as non skin irritant.

Eye irritation

A preliminary consideration has to be made: 1% solution (10 mg/ml) of MG in water has a pH of 1.4. Due to this low pH (< 3.0), the chemical is like to be a corrosive.

In a case it is reported that 1% solution of MG resulted in destructive keratinis with hypopyon (hypopyon is pus in the eye; it is a leukocyte exudate, seen in the anterior chamber, usually accompanied by redness of the conjunctiva) and terminated in bilateral blindness due to corneal opacification (Grant, 1974). In the same book, MG is reported to cause injury ranging in severity from conjunctiva oedema, hyperemia, purulent discharge to total opacification of corneal stroma (Grant, 1974., p. 431).

Clemmensen et al. (1984) tested eye irritation by MG Oxalate. Instillation of 8 % aqueous solution produced market oedema, substantial discharge and slight hyperemia of the conjunctiva, which disappeared after 24 h in two out of three rabbits. Treatment with fine crystals of MG produced a totally opaque corneas, bright red and oedematous conjunctivae up to four days.

Trans-corneal penetration studies revealed lack of detectable concentration of MG in the aqueous humour and showed that it is unlikely to cause intraocular toxicity (Velpandian, 2007). Furthermore in vitro tissue retention studies revealed that increasing the contact time increases tissue concentration of the substance (Velpandian, 2007).

In conclusion, all studies confirm that MG cause severe irritation.

Justification for selection of skin irritation / corrosion endpoint:

Clear results

Justification for selection of eye irritation endpoint:

Most reliable data

Effects on eye irritation: highly irritating

Justification for classification or non-classification

According to CLP regulation (EC1272/2008) Malachite Green Acetate is classified as Eye Dam 1, H318 (Causes serious eye damage).