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Administrative data

Description of key information

The oral LD50 value determined in the rat was between 25-200 mg/kg bw. 
In the acute dermal toxicity study in the rat the LD50 value of diisopropanol-p-toludin was > 2000 mg/kg bw.

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:
16.02.2001 - 10.04.2001
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: OECD guideline and GLP study
Qualifier:
according to
Guideline:
OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)
Version / remarks:
adopted 1996
Deviations:
no
GLP compliance:
yes
Test type:
acute toxic class method
Limit test:
no
Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Harlan Italy S.r.l., 33049 San Pietro al Natisone
- Age at study initiation: 5 to 6 weeks
- Weight at study initiation: 120 to 150 grams
- Fasting period before study: overnight fast prior to dosing
- Housing: polycarbonate cages
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24°C
- Humidity (%): 40-70 %
- Photoperiod (hrs dark / hrs light): 12 hours light and 12 hours dark
Route of administration:
oral: gavage
Vehicle:
corn oil
Details on oral exposure:
DOSE VOLUME APPLIED: 10 mL/kg bw
Doses:
25, 200, 2000 mg/kg bw
No. of animals per sex per dose:
3 males (2000 and 200 mg/kg bw)
3 males and females (25 mg/kg bw)
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Necropsy of survivors performed: yes
- Body weight: at allocation to the study (day -1), prior the dosing (day 1) and on day 8 and 15
- Clinical signs: 1,2 and 4 hours after dosing and daily thereafter for a total of 14 days
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 25 - < 200 mg/kg bw
Based on:
test mat.
Mortality:
25 mg/kg bw: no death
200 mg/kg bw: 2/3 males within 1 hour after dosing
2000 mg/kg bw: 3/3 males within 1 hour after dosing
Clinical signs:
25 mg/kg bw : no clinical signs were observed
200 mg/kg bw: 2/3 males showed convulsions and pronation approximately 5 minutes after dosing
2000 mg/kg bw: 3/3 males showed convulsions appproximately 1 minute after dosing
Body weight:
no outstanding changes in body weight
Gross pathology:
Abnormal content (yellow or pale mucoid or creamy material) in the stomach and in the jejunum of the early decedent male animals.
Skin/fur staining around the perioral/perinasal region in early decedent male animals.
Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LD50
25 mg/kg bw
Quality of whole database:
The oral LD50 is greater than 25 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:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study was performed prior to the implementation of GLP and OECD Guidelines, but meets the principles of an acute inhalation toxicity study.
Qualifier:
no guideline followed
Deviations:
not applicable
Principles of method if other than guideline:
8h inhalation exposure to a saturated test item atmosphere
according to Smyth et al.: Am. Ind. Hyg. Ass. J., 23, 95-107 (1944)
GLP compliance:
no
Test type:
standard acute method
Limit test:
yes
Species:
rat
Strain:
not specified
Sex:
male/female
Details on test animals and environmental conditions:
mean body weight at study start: 203 g
Route of administration:
inhalation
Type of inhalation exposure:
whole body
Vehicle:
air
Details on inhalation exposure:
Two groups of 3 rats per sex were exposed sequentially to the vapors, generated by bubbling 200 l/h air through a substance column of about 5 cm above a fritted glass disc in a glass cylinder for 8 hours.
Analytical verification of test atmosphere concentrations:
no
Duration of exposure:
8 h
Concentrations:
saturated atmophere at 20°C
No. of animals per sex per dose:
3 rats (total of 12 rats tested in two subsequent experiments)
Control animals:
no
Details on study design:
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight
- observation period: 7 days
Sex:
male/female
Dose descriptor:
LC0
Effect level:
other: saturated atmosphere
Based on:
test mat.
Exp. duration:
8 h
Mortality:
none
Clinical signs:
no abnormality detected
Gross pathology:
no abnormality detected
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed

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:
2011-10-25 to 2011-11-10
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: OECD guideline and GLP study
Qualifier:
according to
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 870.1200 (Acute Dermal Toxicity)
Deviations:
no
Qualifier:
according to
Guideline:
other: EU Method B.3 (Acute Toxicity ((Dermal))
Deviations:
no
Qualifier:
according to
Guideline:
other: Japan MAFF Testing Guideline of 12 Nosan No. 8147
Deviations:
no
GLP compliance:
yes (incl. certificate)
Test type:
standard acute method
Limit test:
yes
Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Wiga GmbH, Sandhofer Weg 7, 97633 Sulzfeld, Germany
- Age at study initiation: Young adult animals (male animals approx. 8 weeks, female animals approx. 12 weeks)
- Weight at study initiation: 199-217 g (male) and 237-262 g (female)
- Housing: Makrolon cage, type III; single housing
- Diet: SDS Special Diets Services
- Water : Tap water ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22°C ± 3°C
- Humidity (%): 30 – 70%
- Photoperiod (hrs dark / hrs light): 12 h / 12 h (6.00 a.m. – 6.00 p.m. / 6.00 p.m. – 6.00 a.m.)

Type of coverage:
semiocclusive
Vehicle:
olive oil
Details on dermal exposure:
TEST SITE
- Area of exposure: About 40 cm² (corresponds to at least 10% of the body surface)

REMOVAL OF TEST SUBSTANCE
- Washing : Afterwards removal of the semiocclusive dressing, rinsing of the application site with warm water
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 3.33 mL/kg bw
- Constant volume or concentration used: 60 g/100 mL
- For solids, paste formed: yes, suspension in olive oil Ph. Eur
Duration of exposure:
24 h
Doses:
2000 mg/kg bw
No. of animals per sex per dose:
5 male /5 female
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Individual body weights shortly before administration (day 0), weekly thereafter and on the last day of observation. Recording of clinical signs several times on the day of administration, and at least once daily thereafter each work day for the individual animals.
- Necropsy of survivors performed: yes, necropsy with gross-pathology examination on the last day of the observation period after sacrifice with CO2 in a chamber with increasing concentrations over time.
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Sex:
male
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Sex:
female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Mortality:
No mortality occurred.
Clinical signs:
No systemic clinical signs were observed during clinical examination. For local effects, please refer to the section "Any other information on results inc. tables" below.
Body weight:
The mean body weight of the animals increased throughout the study period within the normal range, with the exception of one female which showed stagnation of body weight during the first post-exposure week, but gained weight in the second week in a normal range.
Gross pathology:
No macroscopic pathologic abnormalities were noted in the animals (5 males and 5
females) examined on the last day of observation.

Nature and duration of local clinical signs in male animals

Animal No.:

1

2

3

4

5

Erythema grade 1

d5 – d9

d5 – d6

d2 - d5

d1 - d5

d5 – d9

Erythema grade 2

d1 – d2

d1 – d2

d1

-

d1 – d2

Edema grade 1

-

-

d2

d1- d2

-

Edema grade 2

d1-d2

d1-d2

d1

-

d1 – d2

Incrustions

d5 – d9

-

-

-

d5- d8

Scaling

-

d5 – d9

-

-

d5 – d9

Nature and duration of local clinical signs in female animals

Animal No.:

1

2

3

4

5

Erythema grade 1

d1

d2

d2

d5

d5

Erythema grade 2

-

d1

d1

d2

d1 – d2

Erythema grade 3

-

-

-

d1

-

Edema grade 1

d1

d1

d1

d1

d1- d2

Scaling

-

-

-

-

d5 – d8

Local effects in male animals

In four male animals well-defined erythema (grade 2) was noted on study day 1, persisted in three of these animals until study day 2 and decreased to very slight erythema (grade 1) on study day 5. This grade persisted up to study day 6 (one animal) or 9 (two animals).

In the fourth of these animals well-defined erythema decreased to very slight and was already seen on study day 2 and persisted until study day 5 after administration. Very slight erythema was seen in the fifth male from study day 1 until study day 5. On study day 1 slight edema (grade 2) was noted in four animals and persisted in three males until day 2. In the fourth male edema decreased to very slight (grade 1) on day 2. In the fifth male very slight edema was observed from study day 1 until day 2. Furthermore incrustations and scaling were noted from study day 5 until study day 8 or 9 in two males, each.

Local effects in female animals

Very slight erythema (grade 1) was noted in one animal on study day 1, while in three others well-defined erythema (grade 2) was noted on study day 1, persisted in one of these animals until study day 2 and decreased to very slight on study day 5. In the other two females very slight erythema was noted on study day 2. Moderated erythema (grade 3) was seen in the fifth animals on study day 1, but decreased step-wise from well-defined erythema on study day 2 to very slight erythema on study day 5. Very slight edema (grade 1) was observed in all females on study day 1 and persisted in one out of these animals until day 2. Furthermore scaling was noted in one female animal from study day 5 until study day 8.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
2 000 mg/kg bw

Additional information

Acute oral toxicity

In an acute oral toxicity study (RTC, 2001), groups of Sprague-Dawley rats were given a single oral dose of 25 mg/kg, 200 mg/kg and 2000 mg/kg diisopropanol-p-toludin.Animals were observed for 14 days. 2/3 animals, administered with 200 mg/kg, died within 1 hour after dosing. 3/3 animals, administered 2000 mg/kg, died within 1 hour after dosing. No clinical signs could be determined in the 25 mg/kg bw dosed group. 2/3 males, administered 200 mg/kg bw, showed convulsion and pronation approximately 5 minutes after dosing. In the highest dosed group (2000 mg/kg bw) 3/3 males showed convulsions approximately 1 minute after dosing. As gross pathology observation could be detected: abnormal content (yellow or pale mucoid or creamy material) in the stomach and in the jejunum of the early decedent male animals. Skin/fur staining around the perioral/perinasal region in early decedent male animals. Changes in body weight observed during the period of the study were within the range expected for this strain and age of animal.The observed mortality pattern demonstrates the LD50 to be less than 200 mg/kg bw and greater than 25 mg/kg bw.

Two additional supporting studies with less reliability are also available:

Within an acute oral toxicity study (BASF AG, 1978) groups of Sprague-Dawley rats (5/sex) were given a single oral dose of 68.1, 100, 147, 215, 316, 464, 681 and 1000 mg/kg diisopropanol-p-toluidin as emulsion in olive oil (concentration in vehicle: 0.316 -10 %). Animals were observed for 14 days. The oral LD50 value for males and females was calculated to be approximate 100 mg/kg bw.

Furthermore, in an acute oral toxicity study (Bayer AG, 1983) groups of Wistar rats were given a single oral dose of 100, 130, 160, 180, 200, 230 and 300 mg/kg bw diisopropanol-p-toludin in DMSO. Animals were observed for 14 days. The oral LD50 value in this study was calculated to be 172 mg/kg bw.The 95% confidence intervall was 154 -190 mg/kg bw.

To conclude, due to the lack of reliable analytical data in the supporting studies in combination with the absence of GLP, the LD50 of diisopropanol-p-toludin is assumed to range between 25 and 200 mg/kg bw, leading to a most conservative approach.

Acute dermal toxicity

In the key acute dermal toxicity study (Bioassay, 2011, according to OECD 402) the potential of diisopropanol-p-toludin to exert systemic toxicity was examined in groups of 5 Wistar rats per sex that were semiocclusively to the limit dose of 2000 mg/kg bw exposed for 24 hours and then observed for 14 days. Mortality incidence, clinical signs and body weights were recorded at regular intervals. All survivors were necropsied and examined macroscopically at the end of the observation period. No animal died and no systemic clinical signs were observed. There was no test item related effect on body weight. No macroscopic pathologic abnormalities were noted at necropsy. Well-defined erythema (max. grade 2, 4/5 animals), edema (max. grade 2, 4/5 animals) incrustions (2/5 animals) and scaling (2/5 animals) were noted for male animals. For female animals well-defined to moderate erythema (grade 2, 4/5 animals; grade 3, 1/5 animal), edema (max. grade 1, 5/5 animals) and scaling (1/5 animals) were observed. All local effects in male and female animals disappeared within maximum 9 days. The identified LD50 value was > 2000 mg/kg bw in male and female rats.

Justification for classification or non-classification

Based on the available data diisopropanol-p-toluidin is subject to C&L:

- category 2, H300 according to Regulation (EC) No. 1272/2008.