α-n-butyl-α-(4-chlorophenyl)-1H-1,2,4-triazole-1-propanenitrile

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

24-June-2005 to 29-September-2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Version / remarks:

1985

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

Version / remarks:

1998

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

α-n-butyl-α-(4-chlorophenyl)-1H-1,2,4-triazole-1-propanenitrile

EC Number:

410-400-0

EC Name:

α-n-butyl-α-(4-chlorophenyl)-1H-1,2,4-triazole-1-propanenitrile

Cas Number:

88671-89-0

Molecular formula:

C15H17ClN4

IUPAC Name:

2-(4-chlorophenyl)-2-[(1H-1,2,4-triazol-1-yl)methyl]hexanenitrile

Test material form:

solid: crystalline

Remarks:

Light orange

Test animals

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Received from Charles River Laboratories, Raleigh, NC on July 5, 2005.
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: Young adult (9 weeks)
- Weight at study initiation: males 171-182 grams and females 118-124 grams
- Housing: The animals were singly housed in suspended stainless steel caging with mesh floors. Litter paper was placed beneath the cage and was changed at least three times per week.
- Diet: Purina Certified Rodent Diet
- Water: Filtered tap water, ad libitum
- Acclimation period: 6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-22°C
- Humidity (%): 66-70%
- Air changes (per hr): Photoperiod (hrs dark / hrs light): 12-hour light/dark cycle

Administration / exposure

Type of coverage:

occlusive

Vehicle:

water

Remarks:

distilled

Details on dermal exposure:

TEST SITE
- % coverage: 10%
- Type of wrap if used: Durapore tape

REMOVAL OF TEST SUBSTANCE
- Washing (if done): The test sites were gently cleansed of any residual test substance
- Time after start of exposure: 24 hours after the start of exposure

TEST MATERIAL
- Amount applied: 5000 mg/kg of body weight of the ground test substance.
Prior to application, the test substance was ground in a coffee mill then moistened with distilled water to achieve a dry paste by preparing a 65% w/w mixture.

Duration of exposure:

24 hours

Doses:

5000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Individual body weights of the animals were recorded prior to test substance application (initial) and again on Days 7 and 14 (termination). The animals were observed for mortality, signs of gross toxicity, and behavioral changes during the first several hours after application and at least once daily thereafter for 14 days.
- Gross necropsies were performed on all animals. The external surface of the body and all orifices, tissues, and organs of the thoracic and abdominal cavities were examined.

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

All animals survived the study period.

Clinical signs:

other: There were no signs of gross toxicity, dermal irritation, adverse clinical signs, or abnormal behavior.

Gross pathology:

No gross abnormalities were noted for any of the animals when necropsied at the conclusion of the 14-day observation period.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of this study, the single dose acute dermal LD50 of Myclobutanil was greater
than 5,000 mg/kg of body weight in male and female rats.

Executive summary:

An acute dermal toxicity test was conducted with Fischer 344 rats. Five thousand milligrams of ground test substance per kilogram of body weight was mixed with distilled water and applied to the skin of five male and five female healthy rats for 24 hours. All animals survived, gained body weight, and appeared active and healthy during the study. There were no signs of gross toxicity, dermal irritation, adverse clinical signs, or abnormal behavior. No gross abnormalities were noted for any of the animals when necropsied at the conclusion of the 14-day observation period. In conclusion, under the conditions of this study, the single dose acute dermal LD50 of the test substance was greater than 5,000 mg/kg of body weight in male and female rats.