(2RS,3RS)-3-(2-chlorophenyl)-2-(4-fluorophenyl)-[(1H-1,2,4-triazol-1-yl)methyl]oxirane

Repeated dose toxicity: dermal

Administrative data

Endpoint:

short-term repeated dose toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Jun 1991 (first study), Nov 1991 (second study)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 410 (Repeated Dose Dermal Toxicity: 21/28-Day Study)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPP 82-2 (Repeated Dose Dermal Toxicity -21/28 Days)

Version / remarks:

Nov 1984

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

(2RS,3RS)-3-(2-chlorophenyl)-2-(4-fluorophenyl)-[(1H-1,2,4-triazol-1-yl)methyl]oxirane

EC Number:

406-850-2

EC Name:

(2RS,3RS)-3-(2-chlorophenyl)-2-(4-fluorophenyl)-[(1H-1,2,4-triazol-1-yl)methyl]oxirane

Cas Number:

133855-98-8

Molecular formula:

C17 H13 Cl F N3 O

IUPAC Name:

1-{[(2R,3R)-3-(2-chlorophenyl)-2-(4-fluorophenyl)oxiran-2-yl]methyl}-1H-1,2,4-triazole

Test animals

Species:

rat

Strain:

Wistar

Details on species / strain selection:

none given

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dr. Karl Thomae, Biberach/Riss, FRG
- Age at study initiation: not specified
- Weight at study initiation: male: 253-283 g (first study), 264-280 g (second study); female: 218-241 g (first study), 211-224 g (second study)
- Fasting period before sacrifice: about 16 h
- Housing: single
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 9 days

DETAILS OF FOOD AND WATER QUALITY: The feed batches used in the study were tested for impurities. The drinking water has been regularly assayed for chemical contaminants.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Air changes (per hr): not specified
- Photoperiod (hrs dark / hrs light): 12/12 (illumination: 6 am to 6 pm)

IN-LIFE DATES: From: May 27, 1991 (first study) and Nov 18, 1991 (second study) To: Jun 26, 1991 (first study), Dec 18, 1991 (second study)

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

0.5% Tylose (cleaned sodium-carboxymethylcellulose in aqua bidest.)

Details on exposure:

TEST SITE
- Area of exposure: dorsal and dorsolateral parts of the trunk
- % coverage: at least 10% of the bodu surface
- Type of wrap if used: (4 layers of absorbent gauze and an elastic dressing).
- Time intervals for shavings or clipplings: at least thrice a week. Only the first clipping was carried out at least 24 hours before the first application.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2 ml/kg
- Concentration (if solution): 1.000; 400 and 100 mg/kg body. Volumes of test substance preparations and solvent (0.5% solution of Tylose CB 30.000 in aqua bidest.) to be applied were calculated for each animal once a week on the day of body weight determination.
- Constant volume or concentration used: yes
- Preparation interval: daily

VEHICLE
- Tylose CB 30.000
- Amount(s) applied (volume or weight with unit): 2 ml/kg
- Concentration (if solution): 0.5%

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

To verify the correctness of the concentrations and the homogeneity of the test substance preparations, samples of each concentration were sent for analysis at the beginning of each study section. The content of the active ingredient was determined by HPLC.

Duration of treatment / exposure:

3 weeks

Frequency of treatment:

6 h per day

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

100 mg/kg bw/day

Doses / concentrations 2

Dose / conc.:

400 mg/kg bw/day

Doses / concentrations 3

Dose / conc.:

1 000 mg/kg bw/day

No. of animals per sex per dose:

5

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: An acute oral toxicity study in the rat, an acute dermal toxicity study in the rat, an acute dermal irritation/corrosivity study to the intact dorsal skin of the white rabbit, and an acute irritation to the eye of the white rabbit
- Rationale for animal assignment (if not random): random
- Other: Treatment had been performed in two consecutive study sections. In the first study section 1,000 mg/kg body weight and in the second study section 400 and 100 mg/kg body weight have been administered. In both study sections respectively, a control group for comparison was used.

Positive control:

not included

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: twice daily (before and after exposure)

DERMAL IRRITATION (if dermal study): Yes
- Time schedule for examinations: daily (about 30 min after removal of the dressing)

BODY WEIGHT: Yes
- Time schedule for examinations: weekly

FOOD CONSUMPTION: Yes
- Time schedule: weekly
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes

FOOD EFFICIENCY: No

WATER CONSUMPTION: No

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: Day 21; Males and females first study June 26, 1991; males and females second study Dec 18, 1991
- Anaesthetic used for blood collection: No
- Animals fasted: Yes
- How many animals: all
- Parameters checked: Leukocytes, erythrocytes, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, platelets, differential blood count, thromboplastin time

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: day 21; Males and females first study June 26, 1991; males and females second study Dec 18, 1991
- Animals fasted: No
- How many animals: all
- Parameters checked: sodium, potassium, chloride, inorganic phosphate, calcium, urea, creatinine, glucose, total bilirubin, total protein, albumin, globulins, triglycerides, cholesterol, magnesium, ALT, AST, ALP, GGT

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
- the exsanguinated animals were necropsied and assessed by gross pathology.
- Organ weights from all animals: liver, kidneys, spleen, testes and adrenal glands

HISTOPATHOLOGY: Yes
- Organs examined for all test groups and all animals: treated skin, normal skin, liver, kidneys, spleen
- all gross lesions: all animals affected per group

Statistics:

Wilcoxon test, Kruskal-Wallis-H-test, Mann-Whitney-U-test, Kruskal-Wallis

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Dermal irritation:

no effects observed

Description (incidence and severity):

No signs of irritation on the treated skin could be observed in test or control animals.
Adhesive tape caused mechanical skin lesions beside the treated area.

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

- 1000 mg/kg bw/day: slight decrease in red blood cells and hematocrit in the peripheral blood in males

No substance—induced changes were observed in the clotting analyses of both sexes

Clinical biochemistry findings:

no effects observed

Description (incidence and severity):

No substance-induced changes were observed in the enzyme activities of both sexes. No substance—induced changes were observed in the clinicochemical examinations of both

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

- 1000 mg/kg bw/day: significantly increased absolute mean liver weights in male and female rats; significantly increased absolute mean kidney weight in female rats, without a morphological equivalent
- 400 mg/kg bw/day: significantly increased relative mean liver weight in female rats, without a morphological equivalent

Gross pathological findings:

no effects observed

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

- 1000 mg/kg bw/day: slight centrilobular liver cell hypertrophy in male rats

Details on results:

The application of 1000 mg/kg body weight to the skin resulted in a treatment related increase of the absolute liver weight in male female rats. In males, a slight (grade 2) hypertrophy of the hepatocytea is in accordance with
the weight increase. Although no morphological alteration was noted in the females, the weight increase most likely represents a treatment related effect, too.
In contrast to this, the observed significant increase of the absolute weight of the testes does not represent a treatment related effect, as two control animals had exceptional low testes weights — due to spontneous tubular atrophy - and hence the mean value of dose group 1 was compared with a too low mean valuein the concurrent control group 0.
Although no morphological observation was made that may explain the significantly increased mean absolute kidney weights in the female rats of dose group 1000 mg/kg, it can not be excluded that this observation represents a marginal toxic effect. Its biologic relevance, however, is of little if any importance. No treatment related effects were seen in the treated skin.
In the untreated skin of the abdomen of one control and four treated females of dose group 1000 mg/kg, crust formation was noted grossly in the abdominal region where the adhesive fleece of the semiocclusive dressing stuck to the skin. This gross lesion proved to be hyperkeratosis, focal acanthosis, crust formation, focal necrosis, and/or dermal fibrosis histopathologically. None of these findings represent a treatment related effect as they are only linked with the technical procedure used for the application of the test article to the treated
site of the skin.
In the second part of the study (control group 00 and dose groups 3 [100 mg/kg body weight] and 2 [400 mg/kg body weight]), the only possible treatment related effect might be traced from the significantly increased relative live: weight of the female rats of dose group 2 (400 mg/kg body weight). However, no microscopic finding was noted that may refer to the increased weight. Moreover, the application
of 1000 mg/kg body weight to the skin did not result in significantly increased relative liver weights in the female rats. Therefore, the significance of this observation is of little if any biological relevance.
The increased absolute kidney weights in the females of dose group 3 are a by chance observation as the mean of this group is lower than that one of dose group 2 which does not show a statistically significant deviation from the concurrent control group 00.
All other gross lesions or microscoPic findings are regarded to have occurred incidentally and they could not be related to the application of the test article.

Effect levels

Dose descriptor:

NOAEL

Effect level:

100 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no adverse effects observed

Target system / organ toxicity

Critical effects observed:

yes

Lowest effective dose / conc.:

400 mg/kg bw/day

System:

hepatobiliary

Organ:

liver

Treatment related:

yes

Dose response relationship:

yes

Any other information on results incl. tables

Table 1: Absolute weights of test groups 0 (control) and 1 (1000 mg/kg bw/day)

ABSOLUTEWEIGHTS- MEANVALUES (FEMALE)-GROUPS 0AND1

 

Sacrifice				group	Fl
				Sex	F
Dose				group	0	1
Body weight			g	M	220.22	228.5
				SD	8.327	16.833
				n	5.	5.
Liver		g		M	7.278	8.788*
				SD	0.44	1.348
				n	5.	5.
Kidneys		g		M	1.876	2.076**
				SD	0.107	0.094
				n	5.	5.
Spleen		g		M	0.54	0.526
				SD	0.02	0.121
				n	5.	5.
Adrenal	glands	mg		M	103.6	111.
				SD	11.739	7.517
				n	5.	5.

ABSOLUTE WEIGHTS - MEAN VALUES (MALE) - GROUPSOAND1

 

Sacrifice			group	Fl
			Sex	M
Dose			group	0	1
Body weightg			M	291.44	306.56
			SD	16.477	11.225
			n	5.	5.
Liver	g		M	10.142	11.428**
			SD	0.702	0.169
			n	5.	5.
Kidneys		g	M	2.486	2.622
			SD	0.186	0.118
			n	5.	5.
Testes		g	M	2.844	3.108*
			SD	0.237	0.178
			n	5.	5.
Spleen		g	M	0.594	0.682
			SD	0.074	0.064
			n	5.	5.
Adrenal	glands	mg	M	86.8	80.4
			SD	14.255	12.502
			n	5.	5.

 

Wilcoxon-Test (two-sided)

* P<=0.05 ** P<=0.01

 Table 2: Relative weights of test groups 00 (control), 3 (100 mg/kg bw/day), and 2 (400 mg/kg bw/day)

 

RELATIVE WEIGHTS - MEAN VALUES (FEMALE) GROUPS 00, 3 AND2

 

Sacrifice group					Fl
Sex					F
Dosegroup					00		3	2
Body weight		M		100.		100.		100.
			SD
			n	5.		5.		5.
Liver		%	M	3.394h		3.544		3.686**
			SD	0.063		0.241		0.186
			n	5.		5.		5.
Kidneys			M	0.877		0.921		0.903
			SD	0.015		0.049		0.097
			n	5.		5.		5.
Spleen		%	M	0.265		0.293		0.254
			SD	0.032		0.039		0.048
			n	5.		5.		5.
Adrenal	glands	%	M	0.049		0.051		0.053
			SD	0,005		0.004		0.009
			n	5.		5.		5.

 

h P<=0.05			:Kruskal-Wallis-H-Test
* P<=0.05**	P	<=0.01	:Kruskal-Wallis-H-+Wilcoxon-Test
two-sided