Dicarbonyl(pentane-2,4-dionato-O,O')rhodium

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Eye test carried out to guideline (US). Limited reporting, notably of test material (e.g. purity).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1978

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: As described in US Federal Register 1973 Eye test.

Deviations:

not specified

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

yes

Remarks:

Affected animals terminated after 3 days - lesion progression/reversibility not assessed

GLP compliance:

no

Remarks:

Predates GLP

Test material

Test material information

Constituent 1

Reference substance name:

Dicarbonyl(pentane-2,4-dionato-O,O')rhodium

EC Number:

238-947-9

EC Name:

Dicarbonyl(pentane-2,4-dionato-O,O')rhodium

Cas Number:

14874-82-9

Molecular formula:

C7H7O4Rh

IUPAC Name:

Dicarbonyl(pentane-2,4-dionato-O,O')rhodium

Details on test material:

- Name of test material (as cited in study report): Rhodium Dicarbonyl Acetylacetonate
- Substance type: Dark coloured metallic powder
- Physical state: Solid
- Lot/batch No.: 61078/XX

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: "Recognised breeders"
- Age at study initiation: 14-16 weeks
- Weight at study initiation: 2.2 kg
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum):ad libitum

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: right eye treated; left eye untreated - control

Amount / concentration applied:

100 mg

Duration of treatment / exposure:

72 hours

Observation period (in vivo):

up to 72 hours

Number of animals or in vitro replicates:

6

Details on study design:

SCORING SYSTEM: Draize method - corneal opacity, iris inflammation, conjunctival irritation

TOOL USED TO ASSESS SCORE: hand-slit lamp

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

corrected cumulative score

Time point:

other: 24, 48, 72 hours

Score:

6.4

Max. score:

80

Reversibility:

not specified

Remarks on result:

other: See Tables 1 and 2

Results 2

Irritation parameter:

iris score

Basis:

mean

Remarks:

corrected cumulative score

Time point:

other: 24, 48, 72 hours

Score:

2.5

Max. score:

10

Reversibility:

not specified

Remarks on result:

other: See Tables 1 and 2

Results 3

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

corrected cumulative score

Time point:

other: 24, 48, 72 hours

Score:

7.5

Max. score:

20

Reversibility:

not specified

Remarks on result:

other: See Tables 1 and 2

Irritant / corrosive response data:

Corneal damage was seen in two of the treated animals at all time points, and in an additional animal at 72 hours. Effects on the iris of four animals was seen at 24 hours but in only two animals at 72 hours. All 6 animals showed redness to the conjunctivae after 24 and 48 hours, the effect also being seen in 5/6 animals at 72 hours. Chemosis and conjunctival discharge was seen in three animals at all time points examined and in one (chemosis) and two (discharge) at 24 hours only. See Table 1 for total and average scores.

Other effects:

No data

Any other information on results incl. tables

Table 1. Individual scores for the group of 6 rabbits

No.	Time/hr	Cornea		Iris	Conjunctivae			Corrected score			Total
		O	A		R	Ch.	Dis.	Cr.	Ir.	Cj.
1	24	1	4	1	1	2	3	20	5	12	37
	48	2	2	1	2	1	1	20	5	8	33
	72	1	4	0	1	2	2	20	0	10	30
2	24	0	0	0	2	1	2	0	0	10	10
	48	Dull	Dull	0	2	0	0	0	0	4	4
	72	0	0	0	1	0	0	0	0	2	2
3	24	0	0	1	2	0	1	0	5	6	11
	48	0	0	0	1	0	0	0	0	2	2
	72	0	0	0	1	0	0	0	0	2	2
4	24	0	0	0	2	0	0	0	0	4	4
	48	0	0	0	1	0	0	0	0	2	2
	72	0	0	0	0	0	0	0	0	0	0
5	24	0	0	1	2	2	2	0	5	12	17
	48	Dull	Dull	1	3	2	1	0	5	12	17
	72	1	2	1	2	2	2	0	5	12	17
6	24	1	3	1	2	3	2	15	5	14	34
	48	1	3	1	3	2	1	15	5	12	32
	72	1	3	1	1	2	2	15	5	10	30

O: Opacity; A: Area; R: Redness; Ch.: Chemosis; Dis.: Discharge; Cr.: Cornea; Ir.: Iris; Cj.: Conjunctivae

Table 2. Total and average score for the group of 6 rabbits

Time	Cornea	Iris	Conjunctivae	Total
24 hours	35	20	59	114
48 hours	35	15	40	90
72 hours	45	10	36	91
Total	115	45	135	295
Average	19.2	7.5	22.5	49.2

All 6 rabbits showed a positive response

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritating to eyes) based on GHS criteria

Conclusions:

In an in vivo eye irritation study, undiluted rhodium dicarbonyl acetylacetonate (0.1 g) produced eye irritation in all six treated albino rabbits, following a 72-hr observation period. The reversibility of the lesions (after 21 days) was not investigated, though the general trend in the irritation scores suggests classification as an eye irritant (category 2) is appropriate.

Executive summary:

In a US guideline in vivo eye irritation study, undiluted rhodium dicarbonyl acetylacetonate (0.1 g) was instilled into the right eye of 6 female New Zealand white rabbits. The animals were assessed for signs of irritation after 24, 48 and 72 hr and the data scored according to the Draize method. The eyes of the treated animals were not rinsed at any time and no observations beyond 72 hours were made.

 

Corneal damage was seen in two of the treated animals at all observation points, and in an additional animal at 72 hr. Effects on the iris of four animals was seen at 24 hours but in only two animals at 72 hours. All 6 animals showed redness to the conjunctivae after 24 and 48 hours, the effect also being seen in 5/6 animals at 72 hours. Chemosis and conjunctival discharge was seen in three animals at all time points examined and in one (chemosis) and two (discharge) at 24 hours only.

 

The reversibility of the lesions (after 21 days) was not investigated. However, the iris and conjunctivae scores showed a general decrease over the three time periods. While the corneal scores were slightly increased at 72 hr due to reactions in a single animal, effects were consistent across the time points in two animals and no corneal effects were observed in the remaining three animals at any time point.

 

The investigators concluded that as all 6 treated animals showed a positive response to the test material it would be classified as an eye irritant according to the US Federal register 1973 Eye Test.

 

All six rabbits showed respective scores for iritis and corneal opacity of less than 1.5 and 3. While the observation period was limited to 3 days (OECD guideline recommends 21 days), there is sufficient evidence to indicate a general reversibility in the observed effects. As such, classification of rhodium dicarbonyl acetylacetonate as an eye irritant (category 2), is appropriate on the basis of the findings of this study and according to EU CLP criteria (EC 1272/2008).