Clioquinol

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from authoritative database.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Principles of method if other than guideline:

The study was conducted with the following objectives:
- To find out the clinical sign of toxicity of the given test chemical at different dose level in wistar albino rats.
- To study the histopathological effect of the given test chemical at different dose level in wistar albino rats.

GLP compliance:

yes

Test type:

other: Acute Dermal Toxicity

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Diiodohydroxyquinoline

EC Number:

201-497-9

EC Name:

Diiodohydroxyquinoline

Cas Number:

83-73-8

IUPAC Name:

5,7-diiodoquinolin-8-ol

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material: diiodohydroxyquinoline
- Molecular formula: C9H5I2NO
- Molecular weight: 396.95
- Substance type: organic
- Physical state: solid

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Institute for Industrial Research and Toxicology Ghaziabad,
- Age at study initiation: 8 to 10 weeks
- Weight at study initiation: 200±20g
- Fasting period before study: Animals were fasted overnight prior to test and food was offered three hours after dosing.
- Housing:Groups of three animals of same sex in polypropylene cages with stainless steel grill top, facilities for food and water bottle, and bedding of clean paddy husk.
- Identification :By cage tag and corresponding colour body marking
- Diet (e.g. ad libitum): Pelleted feed,
- Water (e.g. ad libitum):Fresh and clean water filtered through ‘Aqua Guard on line water filter’, was kept in glass bottles Ad libitum
- Acclimation period: The healthy wistar albino rats selected for study acclimatized to standard laboratory condition for period of one week under close Veterinary supervision.
- Randomization:After acclimation and Veterinary examination all the animals randomly divided into two groups and each group having five male and five female rats.
ENVIRONMENTAL CONDITIONS
- Temperature (°C): Temperature between 22-25°C
- Humidity (%): 40-60%
- Air changes (per hr): Air conditioned rooms with 10-15 air changes per hour
- Photoperiod (hrs dark / hrs light): illumination cycle set to 12 hours artificial fluorescent light and 12 hours dark.

Administration / exposure

Type of coverage:

occlusive

Vehicle:

water

Details on dermal exposure:

TEST SITE
- Area of exposure: back skin of total body surface area
- % coverage: Approximate 10 percent
- Type of wrap if used: The test compound was held in contact with the skin with an impervious dressing secured in place with an adhesive tape.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): The dressing was removed and the site of application was cleaned with lukewarm water wiping the test compound.
- Time after start of exposure: 24 hours

VEHICLE
- Concentration (if solution): The test compound was moistened with distilled water and then applied at the dose level of 2000 mg/kg b.wt.

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

No. of animals per dose group : 10 (5male & 5 female)

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: All the animals were observed for mortality at 30 minutes time interval for first six hours on the day of test compound administration and thereafter twice a day for 14 days. The body weight of all the animals was observed weekly on day 0 (pre treatment), 7th and 14th (post treatment). The treated animals were closely observed for clinical signs of intoxication, first 4 hours and thereafter for every 1 hrs interval for 24 hrs after dosing and twice a day for 14 days. All the rats were observed at least twice daily with the purpose of recording any symptoms of ill-health or behavioral changes. These observations included changes in skin and fur in the eyes and mucous membranes, respiratory, circulatory, central nervous, and autonomic nervous systems, somatomotor activity and behavioral changes. The following clinical signs were observed in female rats to characterize with erythema, hypersensitivity, edema etc.
- Necropsy of survivors performed: yes, necropsy was carried out on all the animals that died during the study or surviving animals were sacrificed at the end of the study to observe any gross pathological changes.

Statistics:

not specified

Results and discussion

Preliminary study:

LIMIT TEST (2000 mg/kg b.wt): Ten healthy wistar albino rats of both sex (ranging b.wt 200±20 gm) selected for study after acclimatization. Approximate 10 percent back skin of total body surface area was prepared 24 hrs prior to application of test compound. The test compound Diiodohydroxyquinoline was applied dermally at the dose level of 2000 mg/kg b.wt for each animal. The treated animals were observed for clinical signs of intoxication and mortality at different time interval for a period of 14 days. The body weight of each rat was observed on day 0 (pre treatment), 7th and 14th (post treatment). The necropsy was performed on all the animals at the termination of the study.

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: No mortality was observed

Mortality:

The test compound when applied dermally at the dose level of 2000 mg/kg b.wt. on Wistar albino rats did not produce any mortality during the observation period of 14 days

Clinical signs:

other: The test compound did not produce any clinical signs when applied dermally at the dose level of 2000mg/kg b.wt. during the observation period of 14 days

Gross pathology:

NECROPSY FINDING
EXTERNAL
i.Skin- Skin and hair coat was observed wet.
ii.All external orifices- Normal
B. INTERNAL
i. Subcutaneous- No changes were observed.
ii. Superficial and deep lymph nodes- No change in mesenteric lymph node.
ABDOMINAL CAVITY
i.Opening and general examination- In the abdominal cavity all the organs were present in normal position.
ii.Spleen- No changes were recorded.
iii.Digestive system- No gross changes were observed in stomach and intestine.
iv.Liver and biliary ducts- No gross pathological changes were observed
v.Excretory system- No gross pathological changes were observed.
vi.Adrenal- Observed normal.
vii.Male/female genital organs – Showed normal colour, consistency and no inflammatory changes.
2. THORACIC CAVITY
i.Opening and general examination- Thoracic cavity was found to be normal without any fluid, mucous or blood etc.
ii.Lungs- No changes were recorded.
iii.Heart- No changes were observed in color and consistency. Heart found normal.
iv.Thyroid- Normal in shape, size and surface.
3. CRANIAL CAVITY
Brain- Normal in shape and size.

Other findings:

not specified

Any other information on results incl. tables

TABLE – 2

SUMMARY OF BODY WEIGHT (GM)

Group	Animal ID	Day 0	Day 7	% Gain/loss	Day 14	% Gain/loss
Group-I 2000 mg/kg b. wt	20166-1	201.23	208.12	3.4	216	7.3
	20166-2	199.21	204.25	2.5	210.11	5.4
	20166-3	205.31	211.51	3.0	216.21	5.3
	20166-4	201.52	209.16	3.7	217.25	7.8
	20166-5	206.32	215.21	4.3	220.24	6.7
	20166-6	203.21	210.31	3.4	217.24	6.9
	20166-7	198.22	206.41	4.1	213.21	7.5
	20166-8	203.15	211.42	4.0	217.12	6.87
	20166-9	202.71	209.31	3.25	218.32	7.7
	20166-10	206.22	217.65	5.5	220.49	6.9
Group-II 2000 mg/kg b. wt	20166-11	201.51	214.51	6.4	216.62	7.4
	20166-12	210.21	217.14	3.2	22.41	5.8
	20166-13	196.42	206.34	5.0	214.33	9.11
	20166-14	203.61	208.51	2.4	211.42	3.83
	20166-15	202.84	212.46	4.7	216.42	6.6
	20166-16	200.14	206.21	3.0	211.54	5.7
	20166-17	201.46	210.64	4.5	217.32	7.8
	20166-18	206.56	217.54	5.3	221.47	7.2
	20166-19	204.67	209.46	2.3	217.75	6.3
	20166-20	203.31	210.10	3.3	216.42	6.4

 TABLE – 3

CLINICAL SIGNS AND MORTALITY

Parameters	Incidence of Clinical Signs Observed after Dosing on																			Mortality
	Day 0					DAY
	Min	Hour
	30	1	2	4	6	1	2	3	4	5	6	7	8	9	10	11	12	13	14	Total	%
Mortality (total)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0/10	0
Clinical Signs- Local
Redness	-	-	-	-	-	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Pain	-	-	-	-	-	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Swelling	-	-	-	-	-	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Systemic signs
Decrease in cage side activity	0	0	0	0	0		0	0	0	0	0	0	0	0	0	0	0	0	0
Lacrimation	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

Group: I Limit test                                                                        Dose: 2000 mg/kg b.wt

                                                                                                                                                          

 

-          =Observed after 24 hrs

0        = No clinical signs

+        = Mild

++      = Moderate

+++    = High

++++  = Severe

TABLE – 3 Contd…………….

CLINICAL SIGNS AND MORTALITY

Group: II Confirmatory test                                                        Dose: 2000 mg/kg b.wt

                                                                                                                                         

Parameters	Incidence of Clinical Signs Observed after Dosing on																			Mortality
	Day 0					DAY
	Min	Hour
	30	1	2	4	6	1	2	3	4	5	6	7	8	9	10	11	12	13	14	Total	%
Mortality (total)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0/10	0
Clinical Signs- Local
Redness	-	-	-	-	-	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Pain	-	-	-	-	-	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Swelling	-	-	-	-	-	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Systemic signs
Decrease in cage side activity	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Lacrimation	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

 

 

-          =Observed after 24 hrs

0        = No clinical signs

+        = Mild

++      = Moderate

+++    = High

++++  = Severe

TABLE – 4

SUMMARY OF NECROPSY FINDINGS

S. No.	Fate	Wistar albino rats
		Dose (mg/kg b. wt)
		2000 (limit test)	2000 (confirmatory test)
1	Terminal sacrifice	10/10	10/10
2	Found Dead	0/10	0/10
3	Abnormalities detected	0/10	0/10

TABLE – 5

INDIVIDUAL ANIMAL FATE & NECROPSY FINDINGS

Group-I (limit test)                                                                         2000 mg/kg b.wt.

Animal ID	Fate	Time	Gross Findings
20166-1	TS	Day 14	NAD
20166-2	TS	Day 14	NAD
20166-3	TS	Day 14	NAD
20166-4	TS	Day 14	NAD
20166-5	TS	Day 14	NAD
20166-6	TS	Day 14	NAD
20166-7	TS	Day 14	NAD
20166-8	TS	Day 14	NAD
20166-9	TS	Day 14	NAD
20166-10	TS	Day 14	NAD

Day 0 is the day of dose administration.

TS- Terminal Sacrifice

NAD- No abnormality Detected

FD-Found dead

TABLE-5 Contd………..

INDIVIDUAL ANIMAL FATE & NECROPSY FINDINGS

Group: II(confirmatory test)                                                     Dose: 2000 mg/kg b.wt.                                                                                

Animal ID	Fate	Time	Gross Findings
20166-11	TS	Day 14	NAD
20166-12	TS	Day 14	NAD
20166-13	TS	Day 14	NAD
20166-14	TS	Day 14	NAD
20166-15	TS	Day 14	NAD
20166-16	TS	Day 14	NAD
20166-17	TS	Day 14	NAD
20166-18	TS	Day 14	NAD
20166-19	TS	Day 14	NAD
20166-20	TS	Day 14	NAD

Day 0 is the day of dose administration.

TS- Terminal Sacrifice

NAD- No abnormality Detected

FD-Found dead

Applicant's summary and conclusion

Interpretation of results:

other: Not classified

Conclusions:

The acute dermal LD50 of the test chemical in Wistar albino rats when applied by dermal route was considered to be >2000 mg/kg b.wt. From this it is concluded that the test chemical is non toxic by dermal route in an acute study of 14 days

Executive summary:

The acute dermal toxicity study of the given test chemical was conducted on Wistar albino rats. This study was conducted according to OECD guideline 402 for testing of chemicals. The summary of the study given as follows - In limit test (2000 mg/kg b.wt) - 10 healthy wistar albino rats of both sex (ranging b.wt 200±20 gm) selected for study after acclimatization. Approximate 10 percent back skin of total body surface area was prepared 24 hrs prior to application of test compound. The test compound was applied dermally at the dose level of 2000 mg/kg b.wt for each animal. The treated animals were observed for clinical signs of intoxication and mortality at different time interval for a period of 14 days. The body weight of each rat was observed on day 0 (pre treatment), 7th and 14th (post treatment). The necropsy was performed on all the animals at the termination of the study. The test chemical applied at the dose level of 2000 mg/kg b.wt in Wistar albino rats did not produce any mortality as well as clinical signs during observation period of 14 days. Necropsy findings did not reveal any significant gross pathological changes. After 72 hrs. a confirmatory test was conducted in same species of animals to confirm the limit test of test compound (OECD-402 guidelines). 10 healthy Wistar albino rats of both sex (ranging b.wt 200±20 gm) selected for study after acclimatization. Approximate 10 percent back skin of total body surface area was prepared 24 hrs prior to application of test compound. The test chemical was applied dermally at the dose level of 2000 mg/kg b.wt for each animal. The treated animals were observed for clinical signs of intoxication and mortality at different time interval for a period of 14 days. The body weight of each rat was observed on day 0 (pre treatment), 7th and 14th (post treatment). The necropsy was performed on all animals which were died during the study or were sacrificed at termination of the study. No mortality was recorded in Wistar albino rats after administration of test chemical at the dose level of 2000 mg/kg b.wt. throughout the observation period. The test chemical applied at the dose level of 2000 mg/kg b.wt. did not produce any clinical signs of intoxication as well as dermal irritation in Wistar albino rats. The body weight of each animal recorded on day 0, 7th and 14th showed normal increase and there was no significant increase or decrease in weight was recorded. Therefore, result obtained from present investigation can be conclude that the acute dermal LD50 of the test chemical in Wistar albino rats when applied by dermal route was considered to be >2000 mg/kg b.wt. From this it is concluded that the test chemical is non toxic by dermal route in an acute study of 14 days