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Administrative data

Description of key information

Acute toxicity: Oral: In an acute oral toxicity study in female Sprague-Dawley rats, following the acute toxicity Up-and-Down method in accordance with the OECD Guideline 425 and EPA OPPTS 870.1100, the LD50 was estimated to be 550 mg/kg body weight (Merrill, 2013). 

Acute toxicity: Inhalation: In an acute inhalation toxicity study in male and female Sprague-Dawley rats, following the Acute Inhalation Toxicity method in accordance with OECD Guidelines 403, Proposal for Updating Guideline 403 and EPA OPPTS 870.1300, the LC50 (inhalative), four hour exposure of test item for male and female rats is therefore >0.66 mg/l (Weniger, 2000). 

 

Acute toxicity: Dermal: In an acute dermal toxicity limit test in male and female New Zealand albino rabbits, following the Product Safety Labs Protocol P322, Acute Dermal Toxicity Limit Test, the LD50 of the test item was determined to be greater than 2000 mg/kg of bodyweight (Moore, 1998).

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records
Reference
Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
September 13, 2013-October 24, 2013
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
Well documented study performed according to OECD guideline 425 and US EPA Health Effects Test Guidelines, OPPTS 870.1100. The deviation from the protocol had no impact on the overall results of the study.
Qualifier:
according to guideline
Guideline:
EPA OPPTS 870.1100 (Acute Oral Toxicity)
Deviations:
yes
Remarks:
The deviation from the protocol had no impact on the overall results of the study.
Qualifier:
according to guideline
Guideline:
OECD Guideline 425 (Acute Oral Toxicity: Up-and-Down Procedure)
Deviations:
yes
Remarks:
The deviation from the protocol had no impact on the overall results of the study.
GLP compliance:
yes
Remarks:
40 CFR 160: EPA GLP Standards: Pesticide Programs (FIFRA), 1989; OECD Principles of GLP (as revised in 1997) published in ENV/MC/CHEM (98)17, OECD, Paris, 19998; EC Directive 2004/10/EC, Official Journal of the European Union, L50/44, Feb. 20, 2004.
Test type:
up-and-down procedure
Limit test:
no
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: MA027180EXA026/ PSL Reference number: 130807-10H
- Expiration date of the lot/batch: November 20, 2018

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature
- Test item handling: The sample was administered as a 60% w/w mixture in distilled water.
- Stability under test conditions: Test item was expected to be stable for the duration of testing.
- Solubility and stability of the test substance in the solvent/vehicle: Soluble in water, methanol and acetone. The sample was administered as a 60% w/w mixture in distilled water. Preliminary sample preparation testing conducted by PSL, indicated that mixtures in excess of 60% (i.e., 70-85%) were too viscous to be administered properly. The test item was expected to be stable for the duration of testing.

OTHER SPECIFICS:
pH: 2.6 @ 0.133% dilution

Species:
rat
Strain:
Sprague-Dawley
Sex:
female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Harlan Laboratories, Inc.
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: young adults, 9-12 weeks old.
- Weight at study initiation: 163-188 g
- Fasting period before study: Overnight
- Housing: The animals were singly housed in suspended stainless steel caging with mesh floors, which conform to the size recommendations in the most recent Guide for the Care and use of Laboratory Animals (Natl. Res. Council, 2011). Enrichment (e.g, toy) was placed in each cage. Litter paper was placed beneath the cage and was changed at least three times per week.
- Diet (e.g. ad libitum): Harlan Teklad Global 16% Protein Roden Diet #2016. The diet was available ad libitum, except during fasting.
- Water (e.g. ad libitum): Filtered tap water was supplied ad libitum.
- Acclimation period: 8-27 days
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-22 degrees C
- Humidity (%): 46-75%
- Air changes (per hr): 12-13
- Photoperiod (hrs dark / hrs light): 12 dark/12 light
Route of administration:
oral: gavage
Vehicle:
water
Remarks:
distilled
Details on oral exposure:
VEHICLE
- Concentration in vehicle: 60% w/w mixture in distilled water
- Amount of vehicle (if gavage): not indicated
- MAXIMUM DOSE VOLUME APPLIED: not indicated
Doses:
174 mg/kg, 550 mg/kg and 2,000 mg/kg
The test item was administered in sequence to animals: 174 mg/kg, 550 mg/kg, 2,000 mg/kg, 550 mg/kg, 174 mg/kg, 550 mg/kg, 174 mg/kg, 550 mg/kg, 174 mg/kg.
No. of animals per sex per dose:
4 females 174 mg/kg and 550 mg/kg; 1 female 2,000 mg/kg.
Control animals:
no
Details on study design:
Details on study design
- Duration of observation period following administration: 14 days or unitl death occurred.
- Frequency of observations and weighing: The animals were observed for mortality, signs of gross toxicity, and behavior changes during the first several hours post-dosing and at least once daily thereafter. Animals were weighed prior to test item administration and again on Days 7 and 14 following dosing or after death.
- Necropsy of survivors performed: yes. Surviving rats were euthanized via CO2 inhalation at the end of the 14-day observation period. Gross necroposies were performed on all decendents and euthanized animals. Tissues and organs of the thoracic and abdominal cavities were examined.
- Other examinations performed: Gross evaluation of skin and fur, eyes and mucous membranes, respiratory, circulatory, autonomic and central nervous systems, somatomotor activity and behavior pattern. Particular attention was directed to observation of tremors, convulsions, salivation, diarrhea, and coma.

Statistics:
The Acute Oral Toxicity (Guideline 425) Statistical Program (Westat, version 1.0, May 2001) was used for all data analyses iincluding: dose progression selections, stopping criteria determinations and /or LD50 and confidence limit calculations.
Key result
Sex:
female
Dose descriptor:
approximate LD50
Effect level:
550 mg/kg bw
Based on:
test mat.
95% CL:
> 234 - <= 853
Remarks on result:
other: the one dose with partial response
Remarks:
The confidence interval is a profile-likelihood based confidence interval
Mortality:
Female dosing sequence 3 at 2,000 mg/kg; Females dosing sequence 4, 6 and 8 at 550 mg/kg.
Clinical signs:
174 mg/kg Dose Level: One animal was hypoactive and exhibited hunched posture, irregular respiration, reduced fecal volume and nasal discharge, but recovered by Day 6 and along with remaining animals appeared active and healthy for the remainder of the 14-day observation period.

550 mg/kg Dose Level: Three animals died within two days of test item administration. Prior to death, the animals exhibited abnormal posture, irregular respiration, reduced fecal volumne, oral discharge, hypoactivity, gasping and/or writhing. The surviving animal was hypoactive and exhibited hunched posture, irregular respiration and reduced fecal volumne, but recovered by Day 3 and appeared active and healthy, gaining body weight for the remainder of the 14-day observation period.

2,000 mg/kg Dose Level: The animal died within one hour of test item administration. There were no clinical sigs noted prior to death.
Body weight:
174 mg/kg Dose Level: All animals survived exposure and gained body weight during the study.

550 mg/kg Dose Level: The surviving animal recovered by Day 3 and gained body weight for the remainder of the 14-day observation period.
Gross pathology:
174 mg/kg Dose Level: No gross abnormalities were noted for the euthanized animals when necropsied at the conclusion of the 14-day observation period.

550 mg/kg Dose Level: Gross necropsy of the decedenets revealed distention of the stomach and intestines. No gross abnormalities were noted for the euthanized animal when necropsied at the conclusion of the 14-day observation period.

2,000 mg/kg Dose Level: Gross necropsy of the decedenets revealed distention of the stomach and intestines
Interpretation of results:
Category 4 based on GHS criteria
Conclusions:
Under the conditions of the study, the acute oral LD50 of the test item is estimated to be 550 mg/kg of body weight (the one dose with partial response) in female rats with a 95% PL confidence interval of 234 mg/kg (lower) to 853 mg/kg (upper). Therefore, the substance is classified as Cat 4 under GHS.
Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LD50
Value:
550 mg/kg bw

Acute toxicity: via inhalation route

Link to relevant study records
Reference
Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
March 24-April 7, 1998
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
Well documented study according to OECD Guideline 403, Proposal for Updating Test Guideline 403 for Acute Inhalation Toxicity and EPA guideline OPPTS 870.1300. No influence of the test results is expected by the deviations.
Qualifier:
according to guideline
Guideline:
OECD Guideline 403 (Acute Inhalation Toxicity)
Version / remarks:
May 12, 1981
Deviations:
yes
Remarks:
No influence of the test results is expected by the deviations.
Qualifier:
according to guideline
Guideline:
EPA OPPTS 870.1300 (Acute inhalation toxicity)
Version / remarks:
June 1996
Deviations:
yes
Remarks:
No influence of the test results is expected by the deviations.
Qualifier:
according to guideline
Guideline:
other: Proposal for Updating Test Guideline 403 for Acute Inhalation Toxicity, OECD, Paris, August 1996.
Version / remarks:
August 1996
Deviations:
yes
Remarks:
No influence of the test results is expected by the deviations.
GLP compliance:
yes
Remarks:
OECD (Environmental Monograph No. 45, OECD, Paris 1992) and of the EPA (40 CFR, part 160).
Test type:
traditional method
Limit test:
yes
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: ZR027180PUE131/Janssen code No. Imazalil sulphate: ZR027180
- Expiration date of the lot/batch: October 15, 2003
- Purity test date: 100% imazalil sulphate (75% as imazalil base equivalent)
- CAS No. 83918-57-4

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: The test item was stirred in the dust generator while pressing dry air through the powder to prevent agglomeration. It was trickled on to an adjustable vibratory metering system. From there it fell into the aerosol flask, was picked up by an air flow and transported to the lower center of the inhalation chamber. Larger particles sedimented within the inner chamber room and smaller ones followed the air stream to the outer chamber and reached the animals.


OTHER SPECIFICS:
Density: 1.46 g/ml at 20 °C
Melting point: 131.5 °C -132.8 °C
Species:
rat
Strain:
Sprague-Dawley
Remarks:
Him:OFA, SPF
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Forschungsinstitut fur Versuchstierzucht, A-2325 Himberg, Austria
- Females (if applicable) nulliparous and non-pregnant: no data
- Age at study initiation: Approximately 9 weeks
- Weight at study initiation: Males: 326-355 grams, Females 213-230 grams.
- Housing: Single caging in Makrolon cages type III (39 cm x 23 cm x 18 cm). Wire mesh lids, with bedding material for laboratory animals, type 4 HV (Finn Tapvie Ky, SF-73600 Kaavi), autoclaved. Bedding changed 1/week.
- Diet (e.g. ad libitum): Altromin No. 1314 forte, gamma irradiated with 25 kGy 60Co, ad libitum, except for the exposure period.
- Water (e.g. ad libitum): Tap water, acidified to pH 3 with HCl, from an automated watering system, ad libitum, except for the exposure period.
- Acclimation period: 6 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): average 22 °C
- Humidity (%): average 55 %
- Air changes (per hr): 12/hr
- Photoperiod (hrs dark / hrs light): Artificial light from 6 am to 6 pm.

Route of administration:
inhalation: dust
Type of inhalation exposure:
nose only
Vehicle:
air
Mass median aerodynamic diameter (MMAD):
8.4 µm
Geometric standard deviation (GSD):
3.4
Remark on MMAD/GSD:
Original Test: 34% of the mass was in the fraction with a diameter of less than 5 µm. The size distribution did not exactly follow a log-normal distribution but had an additonal fraction of particles larger than 16 µm.

1st Amendment: The MMAD was 5.18 µm with a mean gometric standard deviation of 2.52.
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Nose-only inhalation apparatus (TSE, Technical & Scientific Equipment GmbH, Kronberg, Germany, Article No. 504101)
- Exposure chamber volume: The chamber was 30 cm in diameter and 27 cm in height, resulting in a total volume of 19 litres.
- Method of holding animals in test chamber: no data
- Source and rate of air: Central pressure pump (type GA22 from Atlas Copco, Vienna, Austria). The relative humidity was reduced to about 10% in a freeze-dryer (type FD23 from Atlas Copco). The air was filtered oil-free (DEL-Tech filter type 150, DELtech Engineering Ltd, England) and distributed within the Research Center. In the Toxicology Department the pressure was reduced to 3 bar.
- System of generating particulates/aerosols: The test item was stirred in the dust generator (Technical & Scientific Equipment GmbH, Kronberg, Germany, article number 594203) while pressing dry air through the powder to prevent agglomeration. It was trickled on to an adjustable vibratory metering system. From there it fell into the aerosol flask, was picked up by an air flow and transported to the lower center of the inhalation chamber. Larger particles sedimented within the inner chamber room and smaller ones followed the air stream to the outer chamber and reached the animals.
- Administration procedure: Vibratory metering system was adjusted to about 1 g of test item per minute. The air flow was 700 l per hour. Larger particles, about 99% of the test item, were caught in the inner chamber by sedimentation. Smaller particles, about 1% of the test item, reached the outer chamber and the inhalation tubes.
- Method of particle size determination: The size of the dust particles was analysed with a cascade impactor. It contains nine steps with cut-off-diameters from 0.06 um to 16 um. The cut-off diameters were obtained from the manufacturer. About 18 liters of the dust were passed through the impactor within 180 seconds and the amount sedimented in the individual steps was determined gravimetrically after drying. The site of collection was the same as for the analysis. For calculation of the mean particle size, the probit of the fraction of mass smaller than the cut-off diameters was plotted against the logarithm of the cut-off diameters and the liner regresssion of this graph was calculated, preferring the data points around 50%. The diameter, where the regression gives a probit of 5 is the mass mediated aerodynamic diameter (MMAD). The proportion of the diameter at a probit of 6 to the mass mediated diameter is the geometric standard deviation (GSD).
- Treatment of exhaust air: no data
- Temperature, humidity, pressure in air chamber: The temperature inside the chamber was 20.2 to 22.5 °C. The relative humidity ranged from 35.5 % to 42.3%. Air-flow, humidity and temperature: Recording ever half hour.

TEST ATMOSPHERE
- Brief description of analytical method used:
The humidity of the air inside the chamber was measured with a hygrometer (Hygrotest serie 55, type 0555 6020, Testoterm Ges.m.b.H., Vienna, Austria), the temperature with a glass-mercury thermometer. The air flow on the low pressure side (after the generator) was measured with a rotameter (Rota Apparatebau GmbH&Co KG, Wehr, Germany, type L 63/2400-9048, ranging till 2000 l/h). The air flow on the high pressure side (before the generator) was monitored by a rotameter (Fischer & Porter PrazisionsmeBrohr Nr. FP 1/4-10-6-5-81) and by recording the pressure of the air.
Concentration of the test item: At least 6 times during the 4-hour exposure period.
Size distribution of the test item: Once during the 4-hour exposure period.
- Samples taken from breathing zone: yes

CLASS METHOD (if applicable)
- Rationale for the selection of the starting concentration: The target concentration was set according to the Sponsor. 0.5 mg/l is the minimum LC50 for a substance for a classification in toxicity class III.
Analytical verification of test atmosphere concentrations:
yes
Remarks:
Gravimetric analysis. The dust was collected 9 times during the exposure period.
Duration of exposure:
4 h
Remarks on duration:
37 air changes per hour
Concentrations:
Actual concentration: The mean was 655 mg/m3 or 0.66 mg/l.
Nominal concentration: The mean nomimal was 103 g per m3 air (103 mg/l). The recovery of respirable dust was 0.6%
No. of animals per sex per dose:
5 males and 5 females
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observations: 1, 2, 3, 4, 5 and 6 hours after exposure and then at least once a days for a total of 14 days. Body weights: Before exposure and 7 and 14 days after expsoure.
- Necropsy of survivors performed: Yes. All surviving animals were sacrified by CO2 14 days p.a. and examined macroscopically in an attempt to detect possible lesions.
- Other examinations performed: behavior, reactions, physical signs, and body weight.
Statistics:
Statistical evaluation of body weight changes versus the test item concentration.
Key result
Sex:
male/female
Dose descriptor:
LC50
Effect level:
> 0.66 mg/L air
Based on:
test mat.
Exp. duration:
4 h
Remarks on result:
other: General malaise and to signs of damage to the respiratory system. Not life threatening and the animals recovered within a few days.
Mortality:
All animals survived till the end of the study.
Clinical signs:
other: One male and one female animal were normal at each observation term. In the other animals, piloerection, eyelid closure, chromodacryorrhoea, hunched posture and sedation were the most prominent findings, indicating general malaise of the animals. With the
Body weight:
The mean body weights at the day of exposure were 343 g for males and 223 g for females. The mean body weight gain in the first week after the exposure was 15 g for males and 16 g for females. In the second week males gained 42 g, and females 16 g.

One of the females lost weight in the first week after the exposure. In the second week all animals gained weight.
Gross pathology:
Nothing abnormal was seen in any of the animals.
Other findings:
- Other observations: Some observations in life were only seen in males. This may however be an accidental event. As most findings were seen in males and females and as there were not life threatening signs in any of the sexes, no clear sex differences can be established from the results of this study.

The gravimetric determination gave concentrations from 0.45 to 0.85 mg of test item per litre. About 2 hours (1 h 48 min) after the start of the exposure a concentration of less than 0.5 mg per litre was found. Therefore the input of test item was increased until the actual concentration was again higher than 0.5 mg/l. The reason for this lower output remained unclear.

The 1st Amendment was issued on 2000-06-15 because the test item aerodynamic diameter was 8.4 µm which outside the limits of 1-4 µm required by the EPA guideline.

It was therefore requested to prove experimentally if grinding of the test item and using the ground product for preparing the dust would lower the diameter so that it conforms with the limits of 1-4µm.

The grinding of the test item reduced the aerodynamic diameter to some extent but it still remained outside the range of 1-4µm.

Interpretation of results:
GHS criteria not met
Conclusions:
The inhalative exposure of rats to the test item at a concentration of 0.66 mg/l leads to signs of general malaise and to signs of damages to the respiratory system. None of these signs were life threatening and the animals recovered within a few days. At terminal necropsy no abnormal findings were noted. The LC50 (inhalative), four hour exposure of test item for male and female rats is therefore >0.66 mg/l.
Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LC50
Value:
655 mg/m³

Acute toxicity: via dermal route

Link to relevant study records
Reference
Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
May 12, 1998-May 26, 1998
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
comparable to guideline study
Remarks:
Well documented study performed according to Product Safety Labs' Protocol P322. Acute Dermal Toxicity Limit Test
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
Deviations:
no
Remarks:
Reported as Product Safety Labs Protocol P322. Acute Dermal Toxicity Limit Test
GLP compliance:
yes
Remarks:
The study meets the requiremenmts of 40 CFR Part 160 with the following exception: The stability, characterization, identity and verification of the test item concentration as received and tested are the responsibility of the study sponsor.
Test type:
standard acute method
Limit test:
yes
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: ZR027180PUE331/PSL Code Number E80511-2H
- Expiration date of the lot/batch: October 15, 2003
- Purity test date: Imazalil base (75%), inerts (25%)

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature
- Stability under test conditions: Expected to be stable for the duration of testing.
- Solubility and stability of the test substance in the solvent/vehicle: Soluble in water (>500 g/L)

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: Prior to application, the test item was moistened to achieve a dry paste by preparing a 90% w/w mixture in distilled water.
- Final preparation of a solid: The sample was applied as a 90% w/w mixture in distilled water.

Species:
rabbit
Strain:
other: New Zealand albino
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Davidson's Mill Farm, South Brunswick, NJ
- Females (if applicable) nulliparous and non-pregnant: no data
- Age at study initiation: Young adult males and females
- Weight at study initiation: Males-2.3-2.6 kilograms; Females-2.2-2.5 kilograms
- Fasting period before study: no data
- Housing: The animals were singly housed in suspended stainless steel caging with mesh floors which confirm to the size recommendations in the Guide for the Care and use of Laboratory Animals DHEW (NIH) No. 86.23. Litter paper was placed beneath the cage and was changed at least three times per week.
- Diet (e.g. ad libitum): Pelleted Purina Rabbit Chow #5326
- Water (e.g. ad libitum): Filtered tap water was supplied ad libitum by a automatic water dispensing system.
- Acclimation period: 19 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18.3-22.2 °C
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12 hours dark/12 hours light

Type of coverage:
semiocclusive
Vehicle:
water
Remarks:
distilled
Details on dermal exposure:
TEST SITE
- Area of exposure: Dorsal area and trunk. On the day prior to application, a group of animals was prepared by clipping (Oster model #A2-small) the dorsal area and the trunk.
- % coverage: 4 in x 8 in area (approximately 10% of the body surface area)
- Type of wrap if used: The test material was applied to approximately to 4 in x 8 in area and covered with a 4 in x 8 in 6-ply gauze pad. The gauze pad and entire trunk of each animal were then wrapped with a 3 inch Durapore tape to avoid dislocation of the pad and to minimize loss of the test item. Elizabethan collars were placed on each rabbit and they were returned to their designated cages.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Test sites were gently wiped with water and a clean towel to remove residual test material.
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg bodyweight
- Constant volume or concentration used: yes
- For solids, paste formed: Yes, dry paste.

Duration of exposure:
24 h
Doses:
1
No. of animals per sex per dose:
5 males, 5 females
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observations-1 and 3 hours after application of test item and at least once daily thereafater for 14 days or until mortality. Weighing-Days: On day prior to application and then on days 7 and 14.
- Necropsy of survivors performed: yes: All surviving animals were euthanized via sodium pentobarbital on Day 14. A gross necropsy was performed on the decedent and all euthanized animals. Tissues and organs of the thoracic and abdominal cavities were examined.
Statistics:
No statistical analysis was performed.
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Remarks on result:
other: Dermal irritation (eschar and/or erythema and edema) were noted at the dose site of all animals between days 1 and 14.
Mortality:
One male (Male 4428) died within two days of test item application.
Clinical signs:
Male 4428: Toxic signs prior to death included irregular respiration, hypoactivity and prone posture.
With the exception of prone posture, the surviving rabbits exhibited similar clinical signs, as well as reduced food consumption and reduced fecal volume, but recovered by Day 8.

Dermal irritation (eschar and/or erythema and edema) was also noted at the dose site of all animals between Days 1 and 14.
Body weight:
Several animals (Male 4426, Female 4429, Female 4431) exhibited a loss of bodyweights at 7 days, however, all Day 14 bodyweights exceeded those recorded at initiation.
Gross pathology:
The gross necropsy of the decedent revealed discoloration of the lungs and injected veins of the intestines. Gross necropsy findings at terminal sacrifice were unremarkable. No gross abnormalities were noted for the animals necropsied at the conclusion of the study.
Interpretation of results:
GHS criteria not met
Conclusions:
The Single Dose Acute Dermal LD50 of the test item is greater than 2,000 mg/kg of bodyweight.
Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LD50
Value:
2 000 mg/kg bw

Additional information

Acute oral toxicity:

• An acute oral toxicity study with Imazalil Sulfate conducted according to the acute toxicity Up-and-Down Procedure in female Sprague-Dawley rats (OECD Guideline 425 and EPA OPPTS 870.1100) was performed (Merrill, 2013, K1). Initially, the substance was administered to one female Sprague-Dawley rat at 174 mg/kg. Following the Up and Down procedure, eight additional females were dosed at 174, 550 or 2000 mg/kg. The substance was administered as a 60% w/w mixture in distilled water. The rats received a single oral dose of test item, and were observed during 14 days following administration. The animals were observed for mortality, signs of gross toxicity, and behavior changes during the first several hours post-dosing and at least once daily thereafter. Animals were weighed prior to test item administration and again on Days 7 and 14 following dosing or after death. Necropsy of survivors and macroscopic examination were also performed. Internal macroscopic abnormalities were recorded. 

Mortality: At 174 mg/kg, no mortality occurred. At 550 mg/kg, three animals died with within two days of test substance administration and at 2000 mg/kg one animal died within one hour. Clinical signs observed were: 174 mg/kg, one animal was hypoactive and exhibited hunched posture, irregular respiration, reduced fecal volume and nasal discharge, but recovered by Day 6 and along with the remaining animals appeared active and healthy for the remained of the 14-day observation period. At 550 mg/kg, the surviving animal was hypoactive and exhibited hunched posture, irregular respiration, and reduced fecal volume, but recovered by Day 3 and appeared active and healthy, gaining body weight for the remainder of the 14-day observation period. Prior to death, the three animals exhibited abnormal posture, irregular respiration, reduced fecal volume, oral discharge, hypoactivity, gasping and/or writhing. At 2000 mg/kg, there were no clinical signs prior to death. 

Body weight gain: At the 174 mg/kg Dose Level, all animals survived exposure and gained body weight during the study. At the 550 mg/kg Dose Level, the surviving animal recovered by Day 3 and gained body weight for the remainder of the 14-day observation period. 

No gross abnormalities were noted for the euthanized animals when necropsied at the conclusion of the 14-day observation period for rats exposed to 174 mg/kg of test substance. For rats exposed to 550 mg/kg, gross necropsy of the decedents revealed distention of the stomach and intestines. No gross abnormalities were noted for the euthanized animal when necropsied at the conclusion of the 14-day observation period. 2,000 mg/kg, gross necropsy of the decedents revealed distention of the stomach and intestines

The acute oral LD50 value of Imazalil Sulfate in Sprague-Dawley rats was estimated to be 550 mg/kg bw (the one dose with partial response) in female rats with a 95% PL confidence interval of 234 mg/kg (lower) to 853 mg/kg (upper).

• In an acute oral study performed following a method equivalent to the OECD Guideline 401, Imazalil Base was tested on 10 females and 10 males wistar rats per doses. The doses of 160, 320 and 640 mg/kg bw were administrated once and the animals were observed over a period of 14 consecutive days for mortality and clinical signs. The results show that mortality occurred at the dose levels of 320 and 640 mg/kg bw. Males and females at all dose levels presented clinical signs such as ataxia, piloerection, hypotonia, hypothermia, exophthalmia, tremors and excitation. Also, Imazalil was somewhat more toxic in female than in male rats. At the end of the acute toxicity experiment, 14 days after administration of the compounds all surviving animals were normal and the LD50 were 343 (262-448) mg/kg/bw for males and 227 (174-297) mg/kg/bw for females.

This study was added as supportive information to strengthen the read-across approach between Imazalil sulfate and Imazalil base.

Acute inhalation toxicity:

An acute inhalation toxicity study with Imazalil Sulfate according to OECD 403, Proposal for Updating Guideline 403 and EPA OPPTS 870.1300 Acute Inhalation Toxicity in male and female Sprague-Dawley rats was performed (Weniger, 2000). The test item was administered as a single inhalation dose as a dust to rats. The test item was applied for 4 hours at an actual concentration of 0.66 mg/litre air in a nose-only device. Clinical signs of five male and five females rats were observed 1, 2, 3, 4, 5 and 6 hours and at least once a day until day 14. Bodyweight was monitored prior to administration and again at Days 7 and 14 after exposure. Necropsy on the decedent and all euthanized animals. 

All animals survived until the end of the study period. One male and one female animal were normal at each observation term. In the other animals, piloerection, eyelid closure, chromodacryorrhoea, hunched posture and sedation were the most prominent findings, indicating general malaise of the animals. With the exception of one animal which had chromodacryorrhoea until Day 8, all these signs disappeared 2 days after the exposure. Dyspnoea and respiratory murmur were seen in all affected males and lasted until 3 days after the exposure. Other findings which occurred only for a short time in one or two animals each were sunken flanks, increased salivation and retention of faeces. One animal had its head covered with test item dust after exposure. After about 2 hours the animal had cleaned itself. One animal was injured at an extremity when taken out of the inhalation tube. This injury recovered 2 days after the exposure. The mean body weights at the day of exposure were 343 g for males and 223 g for females. The mean body weight gain in the first week after the exposure was 15 g for males and 16 g for females. In the second week males gained 42 g, and females 16 g. One of the females lost weight in the first week after the exposure. In the second week all animals gained weight. No gross abnormalities were noted for the animals necropsied at the conclusion of the study.

The concentration of the test item was monitored at least six times during the 4 hour exposure period. The size distribution of the test item was recorded once during the exposure period and the air-flow, humidity and temperature were recorded every half hour. 

The actual concentration of the dust determined by gravimetric determination was from 0.45 to 0.85 mg of test item per litre. About 2 hours (1 h 48 minutes) after the start of exposure a concentration of less that 0.5 mg per litre was found. Therefore, the input test item was increased until the actual concentration was higher than 0.5 mg/l. The mean concentration of Imazalil Sulfate was 655 mg/m3 or 0.66 mg/l. The mass mediated diameter of the test item dust was 8.4 µm and the temperature inside the chamber was 20.2 to 22.5 °C and the relative humidity ranged from 35.5 % to 42.3%.

The 1st Amendment was issued on 2000-06-15 because the test item aerodynamic diameter was 8.4 µm which outside the limits of 1-4 µm required by the EPA guideline. It was therefore requested to prove experimentally if grinding of the test item and using the ground product for preparing the dust would lower the diameter so that it conforms with the limits of 1-4µm. The grinding of the test item reduced the aerodynamic diameter to some extent, but it still remained outside the range of 1-4µm.

The inhalative exposure of rats to the test item at a concentration of 0.66 mg/l leads to signs of general malaise and to signs of damages to the respiratory system. None of these signs were life threatening and the animals recovered within a few days. At terminal necropsy no abnormal findings were noted. The LC50 (inhalative), four hour exposure of test item for male and female rats is therefore >0.66 mg/l.

Acute dermal Toxicity:

• An acute dermal toxicity study with Imazalil Sulfate according to Product Safety Labs Protocol P322, Acute Dermal Toxicity Limit Test in male and female New Zealand albino rabbits was performed (Moore, 1998). The substance was dissolved in distilled water and applied on a clipped area on the dorsal and trunk at 2000 mg/kg bw. The test item formulation was held in contact with the skin with a dressing consisting of a gauze pad, successively covered with 3 inch Durapore tape. In addition, Elizabethan collars were placed on each rabbit. After 24 hours of exposure, the pads and collars were removed and the test sites gently wiped with water and a clean towel to remove any residual test item. The animals were observed for 14 days. Bodyweight was monitored prior to administration and again at Days 7 and 14. Clinical signs were observed at periodic intervals on the day of dosing and once daily thereafter, until day 14. Necropsy on the decedent and all euthanized animals. Tissues and organs of the thoracic and abdominal cavities were examined. 

One male die within two days of test item application. Toxic signs prior to death included irregular respiration, hypoactivity and prone posture. With the exception of prone posture, the surviving rabbits exhibited similar clinical signs, as well as reduced food consumption and reduced fecal volume, but recovered by Day 8. Dermal irritation (eschar and/or erythema and edema) was also noted at the dose site of all animals between Days 1 and 14. Several animals (Male 4426, Female 4429, Female 4431) exhibited a loss of bodyweights at 7 days, however, all Day 14 bodyweights exceeded those recorded at initiation. The gross necropsy of the decedent revealed discoloration of the lungs and injected veins of the intestines. Gross necropsy findings at terminal sacrifice were unremarkable. No gross abnormalities were noted for the animals necropsied at the conclusion of the study.

The dermal LD50 value of Imazalil Sulfate in New Zealand albino rabbits was established to exceed 2000 mg/kg body weight.

• In an acute dermal toxicity study performed according to OECD 402, Imazalil Base was tested on 5 females and 5 males New Zealand white rabbits per dose. A single dose of 2 g/kg bw was held in contact with the skin of the animals for 24 hours under occlusive patch. The animals were observed over a period of 14 consecutive days for mortality, clinical signs, body weight and gross pathology. There was no mortality observed and body weight and body weight gain were comparable to control. The LD50 of imazalil was then concluded to exceed 2 g/kg body weight.

This study was added as supportive information to strenghten the read-across approach between Imazalil sulfate and Imazalil base.

Justification for classification or non-classification

Based on the results showing an LD50 550 mg/kg bw and according to the criteria laid down in Regulation (EC) No 1272/2008 on classification, labelling and packaging of substances and mixtures, Imazalil Sulfate should be classified as acute oral toxic category 4 and should be labelled as H302: Harmful if swallowed.

 

Based on the results from the acute inhalation toxicity study (general malaise and local signs in the respiratory tract) and according to the criteria laid down in Regulation (EC) No 1272/2008 on classification, labelling and packaging of substances and mixtures, Imazalil Sulfate should not be classified for acute inhalation toxicity.

 

Based on the dermal LD50 exceeding 2000 mg/kg bw, Imazalil Sulfate does not have to be classified and has no obligatory labelling requirement for acute dermal toxicity according to the criteria laid down in Regulation (EC) No 1272/2008.

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