1,3,5-triisopropylbenzene

Endpoint summary

Description of key information

The acute oral LD50 is > 2000 mg/kg bw.

The acute inhalation (aerosol) 4h-LC50 is > 5.0 mg/L.

The acute dermal LC50 is >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:

Jan 15 to May 22, 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Version / remarks:

2001

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class 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: Batch No. 6F11027000
- Expiration date of the lot/batch: 17.11.2016
- Purity: 96%

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, Sandhofer Weg 7, 97633 Sulzfeld, Germany
- Females nulliparous and non-pregnant: Yes
- Age at study initiation: 7-8 wks
- Fasting period before study: 3 hrs
- Housing: In groups of 3 animals in Tecniplast Type 2000P open cages (ca. 10% larger than Eurostandard Type IV cages)
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3°C
- Humidity (%): 30-70%
- Air changes (per hr): 10 air changes per hour
- Photoperiod (hrs dark / hrs light): 12 h light/12 h dark, artificial lighting

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

VEHICLE
- Amount of vehicle (if gavage): 4 mL/ kg bw per gavage
- Justification for choice of vehicle: As the test item's solubility in water is poor, corn oil was used as an organic solvent. Pre­ tests showed that the solubility of the test item in corn oil was sufficient.
- Lot/batch no. (if required): Sigma, Catalogue # 1636
- Purity: 100%

CLASS METHOD
- Rationale for the selection of the starting dose: A starting dose of 2000 mg/kg bw was determined based on information from former studies on the test item (single dose LD50 < 5000 mg/kg bw)

Doses:

Planed: 2000 mg/kg, 300 mg/kg, 50 mg/kg, 5 mg/kg

No. of animals per sex per dose:

6

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: For fatalities: twice within 4h after each application, daily for remainder of observation period thereafter. For clinical signs/behavior: daily. For body weight: once before application, then weekly
- Necropsy of survivors performed: Yes
- Other examinations performed: clinical signs, body weight, organ weights, histopathology, other: clinical signs (behavior) and body weight

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

All animals survived during the planned in-life period. No animals died during the study.

Clinical signs:

other: All animals survived during the planned in-life period. Only one animal (E54/0) showed a slight change of behavior shortly after the application (slight lethargy, piloerection at the head, slight abnormal walk).40 minutes later this change was not detecta

Gross pathology:

During necropsy no alterations were found. Only animal ESS/0 of the second run showed a slightly reddened thyroidea.

Interpretation of results:

GHS criteria not met

Remarks:

according to EC 1278/2008 as amended

Conclusions:

Following the administration of a single dose of 2000 mg/kg body weight of the test item in 6 female rats, no animals died during the study and no animals showed severe suffering or moribundity. A slight reversible change of behavior was detected in one animal as well as minor weight loss in another animal. No distinct changes could be noted during necropsy. The LD50 was therefore expected to overlie 2000 mg/kg bodyweight.

Executive summary:

Following the administration of a single dose of 2000 mg/kg body weight of the test item in 6 female rats, no animals died during the study and no animals showed severe suffering or moribundity. A slight reversible change of behavior was detected in one animal as well as minor weight loss in another animal. No distinct changes could be noted during necropsy. The LD50 was therefore expected to overlie 2000 mg/kg bodyweight.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The database is robust given the number and type of studies available, and consistency of findings.

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:

Apr 22 to Jul 16, 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 436 (Acute Inhalation Toxicity: Acute Toxic Class Method)

Version / remarks:

Version not specified

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class 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: Eastman Chemical Company, Batch No. 6F11027000
- Expiration date of the lot/batch: 17/11/2016
- Purity: 96%

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (Barcelona, Spain)
- Females nulliparous and non-pregnant: Yes
- Age at study initiation: 8 wks
- Weight at study initiation: males: ca. 286 - 278 g; females: ca. 212 - 238 g
- Housing: Bedding material: Capsumlab Lecho_10 (autoclavable)
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 8 days (Acclimatisation to the nose-only restraining tubes was performed for 35 minutes immediately before the exposure)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 16.4-23.7ºC
- Humidity (%): 21-52%
- Photoperiod (hrs dark / hrs light): 12:12, 07.00 to 19.00 CET

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose only

Vehicle:

clean air

Mass median aerodynamic diameter (MMAD):

1.7 µm

Remark on MMAD/GSD:

Geometric Standard Deviation (GSD) on the two PSD determinations (PSD #1 and PSD #2) were 4.3 and 5.4 respectively, which are above the target range (1.5 to 3). Single outliers during weighing may have contributed to these high values. Nevertheless, these values were considered to be acceptable taking into account that more than 89% and 67% of particles were below upper limit of 4µm in PSD #1 and PSD #2 respectively. Hence, the particle size distributions obtained were considered to be respirable to rats and these incidents are considered to have no impact on the quality / integrity of the study.

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: flow-past, nose-only; Exposure chambers type EC-FPC-232 (anodised aluminium) equipped with glass exposure tubes
- Exposure chamber volume: 3L
- Method of holding animals in test chamber: restraint tubes which were positioned radially around the exposure chamber
- Source and rate of air: filtered air from a compressor; 0.5-1.0 L/min through each inhalation tube
- System of generating particulates/aerosols: Nebulizer
- Method of particle size determination: Mean Mass Median Aerodynamic Diameter (MMAD) of particle size distribution during exposure was calculated from two gravimetric measurements
- Temperature, humidity, pressure in air chamber: temperature and relative humidity of the test atmosphere in the exposure chamber was maintained as required by experimental conditions. Air flow was monitored regularly.

TEST ATMOSPHERE
- Brief description of analytical method used:
1. The test item usage determined once per exposure by weighing the amount of the test item before/after exposure to determine the quantity of test item used;
2. Aerosol concentration was determined by gravimetric analysis at least once during each hour of exposure. Test aerosol samples were collected onto a Whatman filter (grade F319-04) using a filter sampling device;
3. Particle size distribution was determined gravimetrically twice during exposure;
4. Temperature and relative humidity in the chamber was measured continuously during exposure; and
5. Actual air flow rate monitored hourly in each group during exposure.
- Samples taken from breathing zone: Not specified; but the exposure system ensured a uniform distribution

CLASS METHOD (if applicable)
- Rationale for the selection of the starting concentration: Several tests were performed to establish the highest stable aerosol concentration achievable that could be maintained at least for 4 hours. Aerosol starting dose of 5 mg/L air was selected as no toxic effects were expected based on the available data.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

ca. 4 h

Remarks on duration:

4 consecutive hours

Concentrations:

mean concentration of 5.0 mg/L air during 4 hours

No. of animals per sex per dose:

3 males and 3 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Examined daily for mortality and morbidity. Clinical observations made hourly during exposure and immediately and 1hr following exposure then once daily thereafter for remainder of observation period. Weights were taken just before the start of the inhalation period, daily from days 2 to 5, then on days 8, 10, 11 and immediately before sacrifice on day 15 of study.
- Necropsy of survivors performed: Yes
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: clinical signs, body weight, post-mortem gross necropsy of abdominal and thoracic cavities and contents. Special attention paid to any change in respiratory tract

Key result

Sex:

not specified

Dose descriptor:

LC50

Effect level:

> 5 mg/L air (nominal)

Based on:

test mat.

Exp. duration:

4 h

Mortality:

All animals survived the scheduled observation period.

Clinical signs:

other: Transient clinical signs of toxicity (reduced mobility, absence of turning reflex, weakness, respiratory crackles)

Body weight:

Body weight stagnation in both sexes, but with a longer duration in females

Gross pathology:

No macroscopic findings were observed during necropsy.

Other findings:

Dirty fur was observed in all animals 1 hour after exposure. In addition, chromodacryorrhea (1 out of 3 males) and mild piloerection (1 out o 3 males and 2 out of 3 females) were recorded 1 hour after exposure. Chromodacryorrhea was not longer observed from day 2 of study onwards but dirty fur (all females) and mild piloerection (1 out o 3 males and 2 out of 3 females) were still present at day 2 of study. These clinical signs were not longer present at day 3 of study

3 deviations from the study plan were reported:

(1)   Geometric Standard Deviation (GSD) on the two PSD determinations (PSD #1 and PSD #2) were 4.3 and 5.4 respectively, which are above the target range (1.5 to 3). Single outliers during weighing may have contributed to these high values. These values were considered to be acceptable taking into account that more than 89% and 67% of particles were below upper limit of 4µm in PSD #1 and PSD #2 respectively. These incidents are considered to have no impact on the quality / integrity of the study.

(2)   Relative humidity and temperature in the husbandry room were sporadically below the optimal ranges during the study. This incident is considered not to have any impact on the quality/integrity of the study, since the relative humidity and temperature decreases were minor and no related clinical signs were recorded due to this incident.

(3)   Coefficient of variation (%CV) in the high level of the exposure chamber was 6.17 %, which is slightly above the acceptance criteria (5%). Nevertheless, this incident is considered not to have an impact on the quality / integrity of the study, since all air flow values were in the range of 0.8-1.0 L/min which is within the airflow range required for inhalation studies to guarantee sufficient air flow supply to the animals during the exposure (0.5-1.0 L/min).

Interpretation of results:

GHS criteria not met

Remarks:

according to EC 1278/2008 as amended

Conclusions:

LC50 of 1,3,5-Triisopropylbenzene was greater than 5.0 mg/L air (gravimetrically determined mean aerosol concentration).

Executive summary:

The acute inhalation toxicity of 1,3,5-triisopropylbenzene was tested according to the acute toxic class method with Sprague-Dawley rats according to OECD TG 436. Treatment of animals with 1,3,5-triisopropylbenzene aerosol resulted in no deaths. However, a toxic effect was observed. This toxic effect was characterized by transient clinical signs of toxicity (reduced mobility, absence of turning reflex, weakness, respiratory crackles) and body weight stagnation in both sexes, but with a longer duration in females.

It was concluded that, under the experimental conditions:

LC50 of 1,3,5-Triisopropylbenzene was greater than 5.0 mg/L air (gravimetrically determined mean aerosol concentration).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LC50

Value:

5 000 mg/m³ air

Quality of whole database:

The database is robust given the number and type of studies available, and consistency of findings.

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:

Mar 03 to May 12, 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

1987

GLP compliance:

yes (incl. QA statement)

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: Batch No. 6F11027000
- Expiration date of the lot/batch: 17. Nov. 2016
- Purity: 96%

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Toxi-Coop Zrt. 1103 Budapest, Cserkesz u. 90
- Females nulliparous and non-pregnant: Yes
- Age at study initiation: young adult rats
- Weight at study initiation: Range in preliminary study = 203 – 237 g. Range in main study = 203-211 g (males) and 230-251 g (females)
- Housing: Type II polypropylene/polycarbonate; rat type cages with a solid floor, stainless steel wire covers and self- feeding baskets. During acclimatization: 3 animals/sex/cage. During the study: animals were housed individually.
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 5 days in preliminary study. 19 days at females, 5 days at males in main study

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3 °C
- Humidity (%): 30 - 70 %
- Air changes (per hr): 10-15 air exchanges/hour by central air-condition system
- Photoperiod (hrs dark / hrs light): Artificial light, from 6 a.m. to 6 p.m.

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: back, shaven
- % coverage: 10% of area of total body surface
- Type of wrap if used: sterile gauze pads and semi occlusive plastic wrap

REMOVAL OF TEST SUBSTANCE
- Washing: residual test item was removed using body temperature water.
- Time after start of exposure: 24 hr

Duration of exposure:

24 hrs

Doses:

Preliminary Study: 2000 mg/kg, 300 mg/kg, 50 mg/kg, 5 mg/kg (all but 2000 mg/kg dose where in a vehicle of sunflower oil)
Main Study: 2000 mg/kg (no vehicle)

No. of animals per sex per dose:

Preliminary study: 2 females/dose
Main study: 5 males and 5 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days for main study; 7 days for preliminary study
- Frequency of observations and weighing: morbidity/mortality observations made twice daily at the beginning and end of the working day. Clinical observation was made at the following intervals: 1h, 5h after the treatment and once each day for 14 days thereafter. Body weight was recorded on day 0 (shortly before the treatment), on day 7 and on day 15 in main study.
- Necropsy of survivors performed: Yes
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: Observations included the skin and fur, eyes and mucous membranes, respiratory, circulatory, autonomic and central nervous system, somatomotor activity and behaviour pattern. Particular attention was directed to the observation of tremors, convulsions, salivation, diarrhoea, lethargy, sleep and coma. All necropsied rats were examined for external appearance. The cranial, thoracic and abdominal cavities were opened and the appearance of the tissues and organs was observed, and any abnormality was recorded with details of its location, colour, shape and size.

Preliminary study:

There were no deaths in preliminary study at 5, 50, 300 and 2000 mg/kg bw dose levels. Based on results of preliminary study, a limit test was performed on a dose of 2000 mg/kg bw.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred after the 24-hour dermal exposure in male and female rats during the study

Clinical signs:

other: No behavioural changes, symptoms of dermal irritation and corrosion or signs of systemic toxity were noted during the study

Gross pathology:

No pathological changes were found related to the effect of the test item during the macroscopic examination of animals.

Internal necropsy finding as pale kidneys was detected in one male animal (No.: 4228) and in two female animals (No.: 3944, 3947). This alteration could not be related to the test item toxic effect, but was regarded an individual variation. Most likely the observation is a congenital anomaly.
Moderate hydrometra was found in female No.: 3931. The hydrometra is physiological finding and connected to the cycle of the animal.

Interpretation of results:

GHS criteria not met

Remarks:

according to EC 1272/2008 as amended

Conclusions:

Under our experimental conditions, the acute dermal LD50 value of the test item 1,3,5-Triisopropylbenzene proved to be greater than 2000 mg/kg bw in male and female Crl:(WI)BR rats.

Executive summary:

The acute dermal toxicity of 1,3,5-triisopropylbenzen was tested according to the standard acute method with Wistar rats according to OECD TG 402. A limit test was carried out. A single group of male and female animals (n=5 animals/sex) was exposed at 2000 mg/kg bw by dermal route. The test item was applied in original form and left in contact with the skin for 24 hours, followed by a 14-day observation period.

Neither male nor female animals treated at 2000 mg/kg bw showed behavioural changes and no systemic toxic signs were noted during the study.

The test item did not cause dermal irritation symptoms as erythema or oedema during 14-day observation period.

The body weight development was undisturbed in all animals.

No macroscopic alterations of organs referred to the systemic toxic effect of the test item were seen during the necropsy.

Under our experimental conditions, the acute dermal LD50 value of the test item 1,3,5-Triisopropylbenzene proved to be greater than 2000 mg/kg bw in male and female Crl:(WI)BR rats.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

The database is robust given the number and type of studies available, and consistency of findings.

Justification for classification or non-classification

Acute Toxicity:

The acute oral LD50 is > 2000 mg/kg bw. Therefore, according to EC 1272/2008 as amended, the test substance does not meet the criteria for acute toxicity (oral) classification.

 

The acute inhalation 4h-LC50 is >5.0 mg/L. Therefore, according to EC 1272/2008 as amended, the test substance does not meet the criteria for acute toxicity (inhalation) classification.

 

The acute dermal LD50 is > 2000 mg/kg bw. Therefore, according to EC 1272/2008 as amended, the test substance does not meet the criteria for acute toxicity (dermal) classification.

 

Specific target organ toxicity – single exposure

No significant health effects which impaired function were reported in the available acute toxicity studies. Therefore, according to EC 1272/2008 as amended, the test substance does not meet the criteria for specific target organ toxicity – single exposure classification.