Uric acid

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

1

Reference substance name:

Uric acid

EC Number:

200-720-7

EC Name:

Uric acid

Cas Number:

69-93-2

Molecular formula:

C5H4N4O3

IUPAC Name:

7,9-dihydro-1H-purine-2,6,8(3H)-trione

Test material form:

solid: particulate/powder

Details on test material:

It was manufactured by MOLAR CHEMICALS Ltd.

Test animals / tissue source

Species:

cattle

Strain:

not specified

Details on test animals or tissues and environmental conditions:

Test System : Isolated Cornea from the eyes of freshly slaughtered cattles
Source : Deonar Abattoir slaughter house, Mumbai, Maharashtra
Bovine Age : Between 1 to 5 years (age of the animals was determined based on the teeth count and horn ring count)
Transportation Condition : Transported under cold condition in Hanks’ Balanced Salt Solution containing antibiotics [e.g., penicillin at 100 IU/mL and streptomycin at 100 μg/mL]

Test system

Vehicle:

other: corn oil

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

750 μL ( 20 w/v% formulation)

Duration of treatment / exposure:

4h

Observation period (in vivo):

90 min at 32C

Duration of post- treatment incubation (in vitro):

90 min at 32C

Number of animals or in vitro replicates:

3/group

Details on study design:

3 parallel treatment were performed with physiological salinates, imidazole ( 20 w/v%), corn oil, uric acid at 20 w/v% in corn oil.
Application volulme was 0.75 ml/ cornea.

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Run / experiment:

3

Value:

ca. 0.46

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Any other information on results incl. tables

Bovine Corneal Opacity and Permeability Test for Uric Acid

 

TABLE 1:In VitroIrritation Score

 

Group : Normal Saline, 0.75 mL
Cornea Holder N°	Io  (LUX)	I (Initial) (LUX)	Initial Opacity Value	I (Post Treatment) (LUX)	Post Treatment Opacity Value	Corr. Opacity Value	OD490 Value	Corr. OD490 Value	IVIS
1	1107	1000	4.69	992	5.04	0.35	0.054	0.009	0.49
2	1112	999	4.93	1006	4.62	-0.31	0.053	0.008	-0.19
3	1098	1030	3.05	1005	4.11	1.06	0.052	0.007	1.17
Mean						0.37	-	0.008	0.49
SD						0.69	-	0.001	0.68

 

Group : Imidazole at 20% (w/v) in normal saline, 0.75 mL
Cornea Holder N°	Io  (LUX)		I (Initial) (LUX)		Initial Opacity Value	I (Post Treatment) (LUX)		Post Treatment Opacity Value	Corr. Opacity Value	Final Opacity Value		OD490 Value	Corr. OD490Value	Final OD490Value		IVIS
4	1056		946		5.05	284		108.72	103.67	103.30		1.623	1.578	1.570		126.85
5	1070		1014		2.62	302		101.74	99.12	98.75		2.983	2.938	2.930		142.70
6	1084		1010		3.34	291		108.99	105.65	105.28		2.15	2.105	2.097		136.74
Mean										102.44		-	2.207	2.199		135.43
SD										3.35		-	0.686	0.686		8.01
Group : Corn Oil, 0.75 mL
Cornea Holder N°		Io  (LUX)		I (Initial) (LUX)		Initial Opacity Value	I (Post Treatment) (LUX)		Post Treatment Opacity Value		Corr. Opacity Value		OD490 Value		Corr. OD490 Value		IVIS
7		1096		1031		2.93	1023		3.27		0.34		0.064		0.019		0.63
8		1099		1011		3.89	999		4.41		0.52		0.060		0.015		0.75
9		1095		1042		2.45	1021		3.31		0.86		0.070		0.025		1.24
Mean											0.57		-		0.020		0.87
SD											0.26		-		0.005		0.32

Keys: IVIS =In VitroIrritation Score, Io =Baseline Reading (With medium but without cornea), I = LUX   Reading with Medium and Cornea, OD₄₉₀= Optical Density at 490 Wave Length, - = Not Applicable, Corr.             = Corrected. Blank OD₄₉₀value = 0.045.

 

TABLE 1 (Continued)

Group : Uric Acid (suspension) at 20% (w/v) in Corn Oil, 0.75 mL
Cornea Holder N°	Io (LUX)	I (Initial) (LUX)	Initial Opacity Value	I (Post Treatment) (LUX)	Post Treatment Opacity Value	Corr. Opacity Value	Final Opacity Value	OD490 Value	Corr. OD490 Value	Final OD490 Value	IVIS
10	1106	1005	4.43	975	5.78	1.35	0.78	0.061	0.016	-0.004	0.72
11	1083	971	5.02	968	5.16	0.14	-0.43	0.119	0.074	0.054	0.38
12	1081	1000	3.65	981	4.48	0.83	0.26	0.066	0.021	0.001	0.28
Mean							0.20	-	0.037	0.017	0.46
SD							0.61	-	0.032	0.032	0.23

Keys: IVIS =In VitroIrritation Score, Io =Baseline Reading (With medium but without cornea), I = LUX   Reading with Medium and Cornea, OD₄₉₀= Optical Density at 490 Wave Length, - = Not Applicable, Corr.             = Corrected. Blank OD₄₉₀value = 0.045.

InitialOpacity Value = [((Io⁄I)-b)/a)], Where I = Initial LUX, Io = Baseline Reading Note: a (0.0251) and b (0.9894) are constant. Example:Initial Opacity Value = [((1107/1000)-0.9894)/0.0251] =4.69

Post TreatmentOpacity Value = [((Io⁄I)-b)/a)], Where, I = Post Treatment LUX, Io = Baseline Reading. Note: a (0.0251) and b (0.9894) are constant. Example:Initial Opacity Value = [((1107/992)-0.9894)/0.0251] =5.04

Corr. Opacity Value = Post Treatment Opacity Value - Initial Opacity Value Example:Corr. Opacity Value = 5.04 – 4.69 =0.35

Final Opacity Value = Corr. Opacity Value – Mean Corr. Opacity Value of Control (Group I) Example:Final Opacity Value= 103.67 – 0.37 =103.30

Corr. OD490Value = OD490Value – Blank OD490Value, Where Blank Value for this trial was 0.045 Example:Corr. OD490Value = 0.054 -0.045 = 0.009

Final OD490Value = Corr. OD490Value –Mean Corr.OD490Valueof Control (Group I) Example:Final OD490Value = 1.578 -0.008 = 1.570

IVIS (Control) = Corr. Opacity Value + (15 x Corrected OD490) Example:IVIS = 0.35 + [15 x 0.009] =0.49

IVIS (Treatment) = Final Opacity Value + (15 x Final OD490) Example:IVIS = 103.30 + (15 x 1.570) =126.85

 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The IVIS cut-off values for identifying test item as inducing serious eye damage (UN GHS Category 1) and test item not requiring classification for eye irritation or serious eye damage (CLP no Category)

Executive summary:

test item not requiring classification for eye irritation or serious eye damage (CLP No Category)

The IVIS score for the corneas treated with 750 μLuric acid(suspension) at 20% (w/v) concentration incorn oilwere found to be 0.46.