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Administrative data

Description of key information

Acute oral toxicity: The test substance was found to have a LD50 of 4615 mg/kg (key study result).

Acute inhalation toxicity: The test substance was found to have an LC50 of >4.99 mg/L.

Acute dermal toxicity: New test not required. Literature data reports LD50 of >5000 mg/kg

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:
3 August- 29 August 1979
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Meets generally accepted scientific standards with acceptable restrictions.
Qualifier:
no guideline followed
Principles of method if other than guideline:
The acute oral toxicity of the test substance, prepared as solutions of varying concentration in corn oil to allow treatment at a constant volume-dosage of 20 ml/kg, was investigated in groups of fasted male and female rates, within the dosage range 2000- 5000 mg/kg. Animals were dosed by gavage.
GLP compliance:
no
Remarks:
Study predates GLP
Test type:
fixed dose procedure
Limit test:
no
Species:
rat
Strain:
other: Charles River CD
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Charles River (UK) Limited, Margate, Kent, England
- Age at study initiation: about 1 month old
- Weight at study initiation: 103- 134 g for males and 94- 119 g for females
- Housing: 5 to a cage (in pairs for preliminary studies) in high density polypropylene cages suspended in racks manufactured by North Kent Plastics Limited. Cages measured 50 x 30 x 18 cm high and were fitted with stainless steel grid floors to facilitate rapid removal of waste material to undertrays, cleaned as necessary. Cages were fitted in the racks in such a way that possible environmental influences arising from their spatial distribution were equilibrated, as far as possible, for each treatment.
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 7 d

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 °C ± 2 °C
- Humidity (%): 50 % ± 10 %
- Air changes (per hr): 17
- Photoperiod (hrs dark / hrs light): 12/12
Route of administration:
oral: gavage
Vehicle:
corn oil
Details on oral exposure:
MAXIMUM DOSE VOLUME APPLIED: 20 ml/kg

Doses were determined according to the fasted bodyweight of animals at the time of dosing. From the results of the preliminary study, main study doses were selected; if the LD50 was less than the maximum practicable single dosage of 5000 mg/kg then groups of 10 animals, evenly divided by sex, would be allocated to 5 different dose-levels separated by a constant geometric progression to cover the presumed LD50. Should all animals survive the maximum practicable dosage, or less than 50 % die, the value of the LD50 would be regarded as lying in excess of this dosage.
Doses:
Preliminary study: 100, 500, 1000, 3000 and 5000 mg/kg
Main study: 2000, 2515, 3162, 3976 and 5000 mg/kg
No. of animals per sex per dose:
Preliminary study: 2/sex/ dose
Main study: 5/sex/dose
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: All animals were observed frequently during the first 6 hours after dosing and at least daily thereafter for any signs of reaction to treatment.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight
Statistics:
The 95% confidence limits were calcaulted by probit analysis.
Preliminary study:
From the results of the preliminary study, the LD50 was expected to be around 5000 mg/kg. The main sign of reaction to treatment was a decrease in motor activity. Necropsy of decedents revealed signs of gastro-intestinal irritation.
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
4 615 mg/kg bw
Based on:
test mat.
95% CL:
>= 4 045 - <= 6 265
Mortality:
11 deaths occured, all within 2.5 hours of dosing.
Clinical signs:
Signs of reaction to treatment consisted of decreased motor activity, ataxia, unconsciousness, bradypnoea and diarrhoea. Survivors were asymptomatic from Day 2 until termination.
Body weight:
Normal bodyweight changes were recorded for survivors over the 14 d period of observation.
Gross pathology:
Necropsy of decedents revealed staining of fur, and fluid and mucoid dilation of the gastro-intestinal tract. Thymic congestion, lung congestion and fluid-filled thoracic cavity occurred in 1 animal.

Necropsy of Day 15 revealed no significant lesions.

See Attachment 1 for further details regarding the distribution of signs and mortality among groups of male and female rats given a single oral dosage of the test substance, at a volume-dosage of 20 ml in corn oil.

Interpretation of results:
other: CLP criteria not met
Conclusions:
The test substance was assessed for acute toxicity via the oral route, administerd by gavage as solutions of varying concetrations in corn oil. The test substance was found to have a LD50 of 4615 mg/kg. Therefore, under the conditions of this study the test substance was not considered to be acutely toxic via the oral route.
Executive summary:

The acute oral toxicity of the test item, prepared as solutions of varying concentration on corn oil to allow treatment at a constant volume-dosage of 20 mL/kg, was investigated in groups of fasted male and female rats of the Charles River CD strain, within the dosage range 2000- 5000 mg/kg. Mortality and signs of reaction to treatment were recorded during a 14 -day period of observation. Decedents and survivors killed on Day 15 were subjected to necropsy.

Signs of reaction to treatment consisted of decreased motor activity, ataxia, unconsciousness, bradypnoea and diarrhoea. Eleven deaths occurred, all within 2 ½ h of dosing. Survivors were asymptomatic from Day 2 until termination.

Necropsy of decedents revealed staining of fur and, fluid and mucoid dilation of gastro-intestinal tract. Thymic congestion, lung congestion and fluid-filled thoracic cavity occurred in 1 animal.

Normal bodyweight changes were recorded for survivors over the 14-d period of observation. Necropsy of Day 15 revealed no significant lesions.

From the observed mortality data, the acute median lethal oral dosage (LD50) and 95 % confidence limits, calculated by probit analysis is 4615 (4045- 6265) mg/kg.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
Value:
4 615 mg/kg bw
Quality of whole database:
Two separate acute toxicity studies via the oral route have been conducted on the test material, namely Lightowler and Gardner (1979) and Gaunt et al (1969). The Lightowler and Gardner (1979) study meets generally accepted scientific standards and is well documented and has been assigned reliability 2. The Gaunt et al (1969) study has significant methodological deficiencies and has been assigned reliability 3. However, the result of this study does support the result that the test item is not considered to be acutely toxic via the oral route.

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:
The study was performed between 06 November 2012 and 12 December 2012.
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 436 (Acute Inhalation Toxicity: Acute Toxic Class Method)
GLP compliance:
yes (incl. QA statement)
Test type:
acute toxic class method
Limit test:
yes
Species:
rat
Strain:
other: RccHan™:WIST
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Harlan Laboratories UK Ltd, Oxon, UK
- Age at study initiation: 8 to 12 weeks
- Weight at study initiation: 200 to 350 g
- Fasting period before study:
- Housing: The animals were housed in groups of three by sex in solid-floor polypropylene cages with stainless steel lids, furnished with softwood flakes
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least 5 d

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19- 25
- Humidity (%): 30- 70
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12
Route of administration:
inhalation: aerosol
Type of inhalation exposure:
nose only
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: cylindrical exposure chamber
- Exposure chamber volume: 30 L
- Method of holding animals in test chamber: Prior to the day of exposure each rat was acclimatised (for approximately 2 h) to a tapered polycarbonate restraining tube. During the day of exposure, each rat was individually held in a tapered, polycarbonate restraining tube fitted onto a single tier of the exposure chamber and sealed by means of a rubber '0' ring. Only the nose of each animal was exposed to the test atmosphere.
- Source and rate of air: The concentration within the exposure chamber was controlled by adjusting the rate of the infusion pump. The extract from the exposure chamber passed through a 'scrubber' trap and was connected with a high efficiency filter to a metered exhaust system. The chamber was maintained under negative pressure.
- System of generating particulates/aerosols: the test item was aerosolised using a glass concentric jet nebuliser located at the top of the exposure chamber. The nebuliser was connected to a plastic syringe attached to an infusion pump, which provided a continuous supply of test item under pressure, and to a metered compressed air supply. Compressed air was supplied by means of an oil free compressor and passed through a water trap and respiratory quality filters before it was introduced to the nebuliser.
- Method of particle size determination: The particle size of the generated atmosphere inside the exposure chamber was determined 3 times during the exposure period using a Marple Personal Cascade Impactor. This device consisted of 6 impactor stages (8.6, 5.5, 3.8, 1.7, 0.86 and 0.41 µm cut points) with stainless steel collection substrates and a back up glass fibre filter, housed in an aluminium sampler. The sampler was temporarily sealed in a sampling port in the animals' breathing zone and a suitable, known volume of exposure chamber air was drawn through it using a vacuum pump. The collection substrates and backup filter were weighed before and after sampling and the weight of test item, collected at each stage, calculated by difference.
The mean amount for each stage was used to determine the cumulative amount below each cut-off point size. In this way, the proportion (%) of aerosol less than 8.6, 5.5, 3.8, 1.7, 0.86 and 0.41 µm was calculated. The resulting values were converted to probits and plotted against Log10 cut-point size. From this plot, the Mass Median Aerodynamic Diameter (MMAD) was determined (as the 50 % point) and the geometric standard deviation was calculated. In addition the proportion (%) of aerosol less than 4 µm (considered to be the inhalable fraction) was determined.
- Temperature, humidity in air chamber: 20 °C, 77- 82 %
- Oxygen concentration: the test chamber was generated to contain at least 19 % oxygen

TEST ATMOSPHERE
- Brief description of analytical method used: GC
- Samples taken from breathing zone: yes, 5 times during the exposure period

TEST ATMOSPHERE (if not tabulated)
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.): 2.67 µm/ 2.77
- Predicted amount less than 4 µm: 65.5 %

CLASS METHOD (if applicable)
- Rationale for the selection of the starting concentration: Following an appropriate equilibration period a single group of 6 rats (3 males and 3 females) was exposed to an atmosphere of the test item for a period of four hours. A target concentration of 5.0 mg/L was used for the exposure. As the mean achieved concentration was 99.8% of target and no deaths occurred, no further levels were required.
Analytical verification of test atmosphere concentrations:
yes
Duration of exposure:
4 h
Concentrations:
Target concentration of 5.0 mg/L
No. of animals per sex per dose:
6/sex/ dose
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: clinical signs, all animals were observed for clinical signs at hourly intervals during exposure, immediately on removal from the restraining tubes at the end of exposure, 1 h after termination of exposure and subsequently once daily for 14 d. Any evidence of overt toxicity was recorded at each observation; bodyweight, individual bodyweights were recorded on arrival, prior to treatment on the day of exposure and on Days 1, 3, 7 and 14
- Necropsy of survivors performed: yes, at the end of the 14 d observation period all animals were killed by intravenous overdose of sodium pentobarbitone. All animals were subjected to a full external and internal examination, and any macroscopic abnormalities were recorded. The respiratory tract was subjected to a detailed macroscopic examination for signs of irritancy or local toxicity
Key result
Sex:
male/female
Dose descriptor:
LC50
Effect level:
> 4.99 mg/L air
Based on:
test mat.
Exp. duration:
4 h
Mortality:
There were no mortalities.
Clinical signs:
other: One day after exposure, all animals exhibited increased respiratory rate, hunched posture and pilo-erection. Animals recovered to appear normal from Days 5 to 7 post exposure.
Body weight:
All males and 2 female animals exhibited slight bodyweight losses on the first day post-exposure. Bodyweight gains were noted in all animals during the remainder of the recovery period, with the exception of 1 female animal which exhibited a bodyweight loss from Days 1 to 3 post-exposure.
Gross pathology:
No macroscopic abnormalities were detected amongst animals at necropsy.

Exposure chamber concentration

The test atmospheres were sampled after theoretical chamber equilibration and then at approximately hourly intervals during the exposure period. The mean values obtained were:

Atmosphere concentration

Mean achieved (mg/L)

Standard deviation

Nominal (mg/L)

4.99

0.20

9.33

 

The chamber flow rate was maintained at 60 L/min providing 120 air changes per hour.

 

The theoretical chamber equilibration time (T99) was 3 minutes* (*the test atmosphere was generated for a total of 10 min prior to animal insertion to ensure test item concentration was being achieved).

Particle size distribution

The particle size analysis of the atmosphere drawn from the animals' breathing zone, was as follows:

Mean achieved atmosphere concentration (mg/L)

Mean mass median aerodynamic diameter (µm)

Inhalable fraction (%, 4 µm)

Geometric standard deviation

4.99

2.67

65.5

2.77

Interpretation of results:
GHS criteria not met
Conclusions:
The test substance was assessed for acute toxicity via the inhalation route, administered by nose only exposure to a mean acheived atmosphere concentration of 4.99 mg/L. The test substance was found to have an LC50 of >4.99 mg/L. Therefore, under the conditions of this study the test substance was not considered to be acutely toxic via the inhalation route.
Executive summary:

A study was performed to assess the acute inhalation toxicity of the test item. The method used was designed to be compatible with that described in the OECD Guidelines for Testing of Chemicals (2009) No. 436 "Acute Inhalation Toxicity - Acute Toxic Class Method".

A group of 6 RCCHan™: WIST strain rats (3 males and 3 females) was exposed to an aerosol atmosphere. The animals were exposed for four hours using a nose only exposure system, followed by a 14 -day observation period.

The mean achieved atmosphere concentration was as follows:

Atmosphere Concentration

Mean Achieved (mg/L)

Standard Deviation

Nominal (mg/L)

4.99

0.20

9.33

 

The characteristics of the achieved atmosphere were as follows:

Mean achieved atmosphere concentration (mg/L)

Mean mass median aerodynamic diameter (µm)

Inhalable fraction (%, 4 µm)

Geometric standard deviation

4.99

2.67

65.5

2.77

The mortality data were summarised as follows:

Mean Achieved Atmosphere Concentration (mg/L)

Deaths

Male

Female

Total

4.99

0/3

0/3

0/6

Common abnormalities noted during the study included increased respiratory rate, hunched posture, pilo-erection and wet fur. Animals recovered to appear normal from Days 5 to 7 post-exposure.

All males and 2 female animals exhibited slight bodyweight losses on the first day post-exposure. Bodyweight gains were noted in all animals during the remainder of the recovery period, with the exception of 1 female animal which exhibited a bodyweight loss from Days 1 to 3 post-exposure.

No macroscopic abnormalities were detected amongst animals at necropsy.

No deaths occurred in a group of six rats exposed to a mean acheived atmosphere concentration of 4.99 mg/L for four hours.

It was therefore considered that the acute inhalation median lethal concentration (4 hr LC50) of the test item was greater than 4.99 mg/L.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Acute toxicity via the oral route: An acute oral toxicity study was performed in the rat. The acute oral toxicity of the test item, prepared as solutions of varying concentration on corn oil to allow treatment at a constant volume-dosage of 20 mL/kg, was investigated in groups of fasted male and female rats of the Charles River CD strain, within the dosage range 2000- 5000 mg/kg. Signs of reaction to treatment consisted of decreased motor activity, ataxia, unconsciousness, bradypnoea and diarrhoea. Eleven deaths occurred, all within 2 ½ h of dosing. Survivors were asymptomatic from Day 2 until termination. Necropsy of decedents revealed staining of fur and, fluid and mucoid dilation of gastro-intestinal tract. Thymic congestion, lung congestion and fluid-filled thoracic cavity occurred in 1 animal. Normal bodyweight changes were recorded for survivors over the 14-d period of observation. Necropsy of Day 15 revealed no significant lesions. From the observed mortality data, the acute median lethal oral dosage (LD50) and 95 % confidence limits, calculated by probit analysis is 4615 (4045- 6265) mg/kg.

 

Acute toxicity via the inhalation route: An acute inhalation study was performed in the rat in in accordance with GLP and OECD Guideline 436. A group of 6 RCCHan™: WIST strain rats (3 males and 3 females) was exposed to an aerosol (mist) atmosphere of the test item with a mean achieved atmosphere concentration of 4.99 mg/L for 4 h using a nose only exposure system, followed by a fourteen day observation period. There were no mortalities and no macroscopic abnormalities were detected amongst animals at necropsy. Common abnormalities noted during the study included increased respiratory rate, hunched posture, pilo-erection and wet fur. Animals recovered to appear normal from Days 5 to 7 post-exposure. All males and 2 female animals exhibited slight bodyweight losses on the first day post-exposure. Bodyweight gains were noted in all animals during the remainder of the recovery period, with the exception of 1 female animal which exhibited a bodyweight loss from Days 1 to 3 post-exposure. No macroscopic abnormalities were detected amongst animals at necropsy.

It was therefore considered that the acute inhalation median lethal concentration (4 hr LC50) of the test item was greater than 4.99 mg/L.

Acute toxicity via the dermal route: Based on literature data, the test substance was assessed for acute toxicity via the dermal route and was found to have an LD50 of >5000 mg/kg.

Justification for classification or non-classification

Acute toxicity via the oral route: The available study has been assigned reliability 2 and is considered as acceptable for classification. The test material was found to have an LD50 of 4615 mg/kg bw and as such, the test item can be considered to be non-classified according to CLP.

Acute toxicity via the inhalation route: The available study has been assigned a reliability 1 and is considered as acceptable for classification. The test material was found to have an LC50 of > 4.99 mg/L and as such, the test item can be considered to be non-classified.

Acute toxicity via the dermal route: Available literature data reports LD50 >5000 mg/kg and as such, the test item can be considered to be non-classified.

STOT-SE: In acute oral and inhalation studies the effects observed were considered not to support classification for STOT-SE.

Aspiration toxicity: Classification not required as the substance is not a hydrocarbon.