1-phenyl-3-pyrazolidone

Endpoint summary

Description of key information

Acute oral toxicity: 

The acute oral toxicity dose (LD50) was considered based on different studies conducted on rats and mice for the test chemical. The LD50 value was considered in between 300-2000 mg/kg bw, for acute oral toxicity. Thus, comparing this range with the criteria of CLP regulation, the given test chemical can be classified in “Category 4” for acute oral toxicity.

Acute Inhalation Toxicity:

The acute inhalation toxicity study need not be conducted because exposure to humans via inhalation route is not likely taking into account due to the low vapour pressure of the test chemical, which is reported to be 0.002173155 Pa. Thus, exposure to inhalable dust, mist and vapour of the chemical is highly unlikely. Therefore this study is considered for waiver. 

Acute Dermal toxicity:

The acute dermal toxicity dose (LD50) was considered based on different studies conducted on rats for the test chemical. The study concluded that LD50 value is >2000 mg/kg bw, for acute dermal toxicity. Thus, comparing this value with the criteria of CLP regulation, the given test chemical cannot be classified for acute dermal toxicity.

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Data is from experimental study report.

Qualifier:

according to guideline

Guideline:

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

Principles of method if other than guideline:

The purpose of this study was to assess the Toxicological profile of test item to a single administration via oral route to Sprague Dawley rats. This study was designed to determine the acute toxicity at fixed dose levels by oral route of the test item.

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: National Institute of Biosciences, Pune.
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: Female rats of the age of approximately 8 to 12 weeks old were used at the commencement of its dosing and its weight were within ± 20% of the mean weight of any animal used for dosing. - Weight at study initiation: Body weights at the start : Body weight range was 195.9 to 202.2 grams.
Female Mean: 198.78 g (= 100 %); Minimum : 195.9 g (- 1.45 %); Maximum : 202.2 g (+ 1.72 %)
- Identification: Each female rat was individually identified by the picric acid marking.
- Fasting period before study: Approximately 16 hours or more.
- Housing: The rats were housed in polycarbonate cages.
- Diet (e.g. ad libitum): Rodent feed supplied by the Nutrivet Life Sciences, Pune, was provided ad libitum from individual feeders.
- Water (e.g. ad libitum): Water was provided ad libitum from individual bottles attached to the cages. All water was from a local source and passed through the reverse osmosis membrane before use.
- Acclimation period: 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20.1 to 22.1 degree centigrade.
- Humidity (%): 56.6% to 60.1%.
- Air changes (per hr): Ten to fifteen air changes per hour.
- Photoperiod (hrs dark / hrs light): An artificial light and dark cycle of 12 hours each was provided to the room.

IN-LIFE DATES: 04-07-2017 to 19-09-2017

Route of administration:

oral: gavage

Vehicle:

water

Remarks:

Distilled water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 300 mg/kg, 300 mg/kg and 2000 mg/kg

MAXIMUM DOSE VOLUME APPLIED: 10 ml/kg body weight.

Doses:

Dose Group I : 300 mg/kg
Dose Group I : 300 mg/kg
Dose Group II : 2000 mg/kg

No. of animals per sex per dose:

Three females were used at each step.

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Twice daily
- Necropsy of survivors performed: Yes
- Other examinations performed: Clinical Observations and General Appearance: Animals were observed for clinical signs, mortality and morbidity, until sacrifice.
Onset, duration and severity of any sign were recorded. The clinical signs and mortality observations were conducted at immediately (0 to 5 minutes), 5, 10, 30, 60 minutes, 2, 4 and 6 hours on the day of dosing and once daily thereafter for 14 day. Daily observation was done as far as possible at the same time.
The observations were included general clinical signs, observations of eyes, mucous membranes, respiratory, circulatory system and behavior pattern.

Body weights: Individual animal body weights were recorded, before fasting, prior to administration of the test item (fasting body weights), weekly thereafter and at termination on day 14. Weight changes were calculated and recorded.

Gross Pathology: Necropsy was performed on all animals, found dead and sacrificed at the end of the study. Macroscopic examination of all the orifices, cavities and tissues were made and the findings were recorded. All animals surviving the study period were sacrificed by the carbon dioxide asphyxiation technique (day 15).

Histopathology: Gross pathological examination revealed unabsorbed residual test item in distended stomach in found dead animals from 2000 mg/kg dose group. No gross pathological changes attributable to the treatment were observed in stomach and hence no histopathology was considered.

Statistics:

not specified

Preliminary study:

not specified

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - <= 2 000 mg/kg bw

Based on:

test mat.

Mortality:

Group I Step I : Animals treated at the dose level of 300 mg/kg body weight: All animals survived through the study period of 14 days.
Group I Step II : Animals treated at the dose level of 300 mg/kg body weight: One animal died at 6 hours after the dosing.
Group II Step I : Animals treated at the dose level of 2000 mg/kg body weight: Three animals died at 1 hour after the dosing.

Clinical signs:

Group I Step I : Animals treated at the dose level of 300 mg/kg body weight resulted in distension, piloerection, reduced locomotor activity, ataxic gait and tremors with onset at 30 minutes to 2 hours after the dosing. All animals were free of signs of toxicity from day 4 to day 5 after the dosing.
Group I Step II : Animals treated at the dose level of 300 mg/kg body weight resulted in distension, piloerection, reduced locomotor activity, ataxic gait, tremors and loss of righting reflex with onset at 30 minutes to 4 hours after the dosing. All surviving animals were free of signs oftoxicity from day 4 to day 5 after the dosing.
Group II Step I : Animals treated at the dose level of 2000 mg/kg body weight resulted in reduced locomotor activity, ataxic gait, tremors and convulsions with onset at 5 to 30 minutes after the dosing.

Body weight:

Group I Step I (300 mg/kg) - Percent body weight gain after 7 days and 14 days was found to be 4.31% and 12.09% respectively.
Group I Step II (300 mg/kg) - Percent body weight gain after 7 days and 14 days was found to be 4.79% and 12.10% respectively.
Group II Step I (2000 mg/kg) - All animals died at 1 hour, hence, body weight gain could not be calculated.

Gross pathology:

Gross pathological examination did not reveal any abnormalities in found dead animal and animals sacrificed terminally from 300 mg/kg dose group.
Gross pathological examination revealed stomach distended with unabsorbed residual test item in found dead animals from 2000 mg/kg dose group.

Other findings:

not specified

Table No. I

Summary of Clinical Signs of Toxicity and Mortality

Test System : Sprague Dawley Rat

Sex : Female

Group I :   

Step No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days From - to	Mortality
I	300	Distension	2	2 3	2 hrs. - day 1 2 hrs. - 6 hrs.	0/3
		Piloerection	3	1 2,3	2 hrs. - 4 hrs. 2 hrs.
		Reduced locomotor activity	3	1 2 3	30 min. - 6 hrs. 1 hr. - day 3 30 min. - day 1
		Ataxic gait	3	1 2,3	30 min. - day 3 30 min. - day 4
		Tremors	3	1 2,3	2 hrs. 1 hr. - 2 hrs.

 

Group I : 

Step No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days From - to	Mortality
II	300	Distension	3	4,6 5	1 hr. - 4 hrs. 1 hr. - 6 hrs.	1/3
		Piloerection	2	5 6	4 hrs. - day 2 4 hrs. - 6 hrs.
		Reduced locomotor activity	3	4 5 6	30 min. - 4 hrs. 30 min. - 6 hrs. 30 min. - day 3
		Ataxic gait	3	4 5 6	30 min. - 4 hrs. 30 min. - day 3 30 min. - day 4
		Tremors	3	4,6 5	1 hr. - 4 hrs. 1 hr. - day 2
		Loss of righting reflex	1	4	1 hr. - 4 hrs.

 

Group II :

Step No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days From - to	Mortality
I	2000	Reduced locomotor activity	3	7,8,9	10 min. - 30 min.	3/3
		Ataxic gait	3	7,8,9	5 min. - 30 min.
		Tremors	3	7,9 8	10 min. - 30 min. 30 min.
		Convulsion	3	7,8,9	30 min.

 

 

Table No.II

Mean Body Weight and Percent Body Weight Gain (g)

Test System : Sprague Dawley Rat

Sex : Female

Group I :

Step No.	Dose (mg/kg body weight)		Before Fasting Body weight	Body weight Day 7	% body weight gain day 0-7	Body weight Day 14	% body weight gain day 7- 14	% body weight gain day 0- 14
I	300	Mean	198.23	206.77	4.31	222.20	7.46	12.09
		± SD	1.61	1.29	0.69	2.82	0.69	1.11

 

 

Group I :

Step No.	Dose (mg/kg body weight)		Before Fasting Body weight	Body weight Day 7	% body weight gain day 0-7	Body weight Day 14	% body weight gain day 7- 14	% body weight gain day 0- 14
II	300	Mean	198.57	206.55	4.79	220.95	6.97	12.10
		± SD	2.81	4.03	1.14	3.75	0.27	0.94

 

 

Group II :

Step No.	Dose (mg/kg body weight)		Before Fasting Body weight	Body weight Day 7	% body weight gain day 0-7	Body weight Day 14	% body weight gain day 7- 14	% body weight gain day 0- 14
I	2000	Mean	199.53	-	-	-	-	-
		± SD	2.52	-	-	-	-	-

 

 

Table No.III

Summary of Gross Pathological Findings

Test System : Sprague Dawley Rat

Sex : Female

 

Group I :

Step No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	300	1, 2, 3	TS	No abnormality detected

 

 Group I :

Step No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
II	300	4	FD	No abnormality detected
		5, 6	TS

 

Group II : 

Step No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	2000	7, 8, 9	FD	Stomach : Distended with unabsorbed residual test item.

 FD = Found dead

TS = Terminal Sacrifice

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

Under the condition of the study, the acute oral LD50 value of the given test chemical was considered in between 300-2000 mg/kg body weight. Thus, it was concluded that the acute toxicity study of test chemical, when administered via oral route in Sprague Dawley rats falls into the “Category 4 (300 – ≤ 2000)” criteria of CLP.

Executive summary:

The reported study was designed and conducted to determine the acute oral toxicity profile of the given test chemical as per OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method) in Sprague Dawley rats.

Initially, three female animals were treated at the dose level of 300 mg/kg body weight of the test item (Step - I). Administration of the test item at 300 mg/kg resulted in distension, piloerection, reduced locomotor activity, ataxic gait and tremors with onset at 30 minutes to 2 hours after the dosing.

As no mortality was observed at 24 hours after the dosing, three female animals were added to the study and treated with the same dose of 300 mg/kg of the test item (Step - II). Administration of the test item at 300 mg/kg resulted in distension, piloerection, reduced locomotor activity, ataxic gait, tremors and loss of righting reflex with onset at 30 minutes to 4 hours after the dosing. One animal died at 6 hours after the dosing.

One mortality was observed at 300 mg/kg dose group, hence additional three female animals were treated with the higher dose of 2000 mg/kg of the test item (Step - I). Administration of the test item at 2000 mg/kg resulted in reduced locomotor activity, ataxic gait, tremors and convulsions with onset at 5 to 30 minutes after the dosing. Three animals died at 1 hour after the dosing.

All surviving animals from 300 mg/kg dose group exhibited normal body weight gain through the study period of 14 days. Gross pathological examination did not reveal any abnormalities in found dead animal and animals sacrificed terminally from 300 mg/kg dose group. Gross pathological examination revealed stomach distended with unabsorbed residual test item in found dead animals from 2000 mg/kg dose group.

Under the condition of the study, the acute oral LD50 value of the given test chemical was considered in between 300-2000 mg/kg body weight. Thus, it was concluded that the acute toxicity study of test chemical, when administered via oral route in Sprague Dawley rats falls into the “Category 4 (300 – ≤ 2000)” criteria of CLP.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

1 000 mg/kg bw

Quality of whole database:

Data is Klimisch 1 and from study report.

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

other justification

Justification for data waiving:

other:

Endpoint conclusion

Quality of whole database:

Waiver

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Data is from experimental study report.

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Principles of method if other than guideline:

This study was designed to determine the dermal LD50 of the test item (up to 2000 mg/kg) or to establish a non-lethal dose level of 2000 milligram of test item per kilogram of body weight.

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: National Institute of Biosciences, Pune.
- Females (if applicable) nulliparous and non-pregnant: No data available
- Age at study initiation: Young adult male and female rats aged between 8 – 12 weeks were used.
- Weight at study initiation: The weight range of approximately 211.3 to 235.7 grams at initiation of dosing.
Body weights at the start : Male Mean: 233.06 g (= 100 %); Minimum : 228.8 g (- 1.83 %); Maximum : 235.7 g (+ 1.13 %)
Female Mean: 216.42 g (= 100 %); Minimum : 211.3 g (- 2.37 %); Maximum : 220.0 g (+ 1.65 %)
- Identification: Each rat was individually identified by the cage number.
- Housing: The rats were individually housed in polycarbonate cages with paddy husk as bedding.
- Diet (e.g. ad libitum): Rodent feed supplied by the Nutrivet Life Sciences, Pune, was provided ad libitum from individual feeders.
- Water (e.g. ad libitum): Water was provided ad libitum from individual bottles attached to the cages. All water was from a local source and passed through the reverse osmosis membrane before use.
- Acclimation period: 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19.6 to 22.6 degree centigrade.
- Humidity (%): 55.1% to 59.7%
- Air changes (per hr): Ten to fifteen air changes per hour.
- Photoperiod (hrs dark / hrs light): An artificial light and dark cycle of 12 hours each was provided to the room.

IN-LIFE DATES: 04-07-2017 to 19-09-2017

Type of coverage:

occlusive

Vehicle:

water

Remarks:

(Distilled water)

Details on dermal exposure:

TEST SITE
- Area of exposure: Trunk (dorsal surface and sides from scapular to pelvic area)
- % coverage: Approximately 10% of the body surface area.
- Type of wrap if used: Porous gauze dressing and non-irritating tape.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Distilled water was used to remove residual test item.

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg bw
- For solids, paste formed: Yes

Duration of exposure:

24 hours

Doses:

A single dose of 2000 mg of the test item per kilogram of body weight was administered to ten rats (five males and five females).

No. of animals per sex per dose:

10 (5/sex).

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Twice daily
- Necropsy of survivors performed: Yes
- Other examinations performed:
Clinical Observations and General Appearance: Animals were observed for clinical signs, mortality, until sacrifice. Onset, duration and severity of any sign were recorded. The clinical signs and mortality observations were conducted at 10, 30, 60 minutes, 2, 4 and 6 hours on the day of dosing and once daily thereafter for 14 day. Daily observation was done as far as possible at the same time. The observations were included general clinical signs, observations of eyes, mucous membranes, respiratory, circulatory system and behavior pattern.

Evaluation of Dermal Reaction: Dermal reaction was observed daily for study period of 14 days.

Body weights: Individual animal body weights were recorded pre-test (prior to administration of the test item), day 7 and at termination on day 14.

Gross Pathology: Necropsy was performed on animals surviving at the end of the study. Macroscopic examination of all the orifices, cavities and tissues were made and the findings were recorded. All animals surviving the study period were sacrificed by the carbon dioxide asphyxiation technique (day 15).

Histopathology: No gross abnormalities were observed in animals sacrificed terminally hence, no histopathology was performed.

Statistics:

not specified

Preliminary study:

not specified

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

Sex : Male Group I - Animal treated at the dose level of 2000 mg/kg: All animals survived through the study period of 14 days.
Sex : Female Group I – Animal treated at the dose level of 2000 mg/kg: All animals survived through the study period of 14 days.

Clinical signs:

Sex : Male Group I - Animal treated at the dose level of 2000 mg/kg body weight did not result in any signs of toxicity during the study period of 14 days.
Sex : Female Group I - Animal treated at the dose level of 2000 mg/kg body weight did not result in any signs of toxicity during the study period of 14 days.

Body weight:

Sex : Male Group I (2000 mg/kg) - Percent body weight gain after 7 days and 14 days was found to be 10.37% and 21.31% respectively.
Sex : Female Group I (2000 mg/kg) - Percent body weight gain after 7 days and 14 days was found to be 4.21% and 9.81% respectively.

Gross pathology:

Gross pathological examination did not reveal any abnormalities in animals from 2000 mg/kg dose group.

Other findings:

- Other observations: Evaluation of Dermal Reaction
Sex : Male Group I - Animal treated at the dose level of 2000 mg/kg body weight did not result in any skin reaction during the study period of 14 days.
Sex : Female Group I - Animal treated at the dose level of 2000 mg/kg body weight did not result in any skin reaction during the study period of 14 days.

Table No. I

Summary of Clinical Signs of Toxicity and Mortality

Test System : Sprague Dawley Rat

Sex : Male

Group  No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	2000	No clinical signs observed	5	1 - 5	Day 0 - Day 14	0/5

 

 

Sex : Female

Group  No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	2000	No clinical signs observed	5	6 - 10	Day 0 - Day 14	0/5

 

Table No. II

Summary of Evaluation of Dermal Reaction

Test System : Sprague Dawley Rat

Sex : Male 

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	2000	No dermal reaction observed	5	1 - 5	Day 0 - Day 14	0/5

 

Sex : Female

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	2000	No dermal reaction observed	5	6 - 10	Day 0 - Day 14	0/5

 

 

 

 

Table No.III

Mean Body Weight and Percent Body Weight Gain (g)

Test System : Sprague Dawley Rat

Sex : Male

Group No.	Dose (mg/kg body weight)		Body weight Day 0	Body weight Day 7	% body weight gain day 0-7	Body weight Day 14	% body weight gain day 7- 14	% body weight gain day 0- 14
I	2000	Mean	233.06	257.18	10.37	282.68	9.93	21.31
		± SD	2.83	4.98	3.00	4.06	1.14	2.69

 

 

 

Sex : Female

Group No.	Dose (mg/kg body weight)		Body weight Day 0	Body weight Day 7	% body weight gain day 0-7	Body weight Day 14	% body weight gain day 7- 14	% body weight gain day 0- 14
I	2000	Mean	216.42	225.56	4.21	237.70	5.38	9.81
		± SD	3.60	7.69	2.26	8.55	1.19	2.32

 

Table No.IV

Summary of Gross Pathological Findings

Test System : Sprague Dawley Rat

Sex : Male

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	2000	1 - 5	TS	No abnormality detected

Sex : Female 

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	2000	6 - 10	TS	No abnormality detected

  TS = Terminal Sacrifice

Interpretation of results:

other: Not classified

Conclusions:

It was concluded that the acute dermal median lethal dose (LD50) of the given test chemical, when administered to male and female Sprague Dawley rats was considered to be >2000 mg/kg body weight. Thus, according to CLP criteria for acute toxicity rating for the chemicals, it infers that the given test chemical does not classify as an acute dermal toxicant.
CLP Classification: “Not classified”.

Executive summary:

The reported study was designed and conducted to determine the acute dermal toxicity profile of the given test chemical as per OECD Guideline 402 (Acute Dermal Toxicity) in Sprague Dawley rats.

The test item was applied to shorn skin of 5 male and 5 female animals at 2000 mg/kg body weight. Administration of the test item at 2000 mg/kg did not result in any skin reaction at the site of application during the study period of 14 days. Administration of the test item did not result in any signs of toxicity and mortality during the study period of 14 days.

Animals exhibited normal body weight gain through the study period of 14 days. Gross pathological examination did not reveal any abnormalities attributable to the treatment.

It was concluded that the acute dermal median lethal dose (LD50) of the given test chemical, when administered to male and female Sprague Dawley rats was considered to be >2000 mg/kg body weight. Thus, according to CLP criteria for acute toxicity rating for the chemicals, it infers that the given test chemical does not classify as an acute dermal toxicant.

CLP Classification: “Not classified”.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

Data is Klimisch 1 and from study report.

Additional information

Acute oral toxicity:

In different studies, the given test chemical has been investigated for acute oral toxicity to a greater or lesser extent. Often are the studies based on in-vivo experiments in rodents,

i.e. most commonly in rats and mice for test chemical. The studies are summarized as below -

 

The reported key study was designed and conducted to determine the acute oral toxicity profile of the given test chemical as per OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method) in Sprague Dawley rats.

Initially, three female animals were treated at the dose level of 300 mg/kg body weight of the test item (Step - I). Administration of the test item at 300 mg/kg resulted in distension, piloerection, reduced locomotor activity, ataxic gait and tremors with onset at 30 minutes to 2 hours after the dosing.

As no mortality was observed at 24 hours after the dosing, three female animals were added to the study and treated with the same dose of 300 mg/kg of the test item (Step - II). Administration of the test item at 300 mg/kg resulted in distension, piloerection, reduced locomotor activity, ataxic gait, tremors and loss of righting reflex with onset at 30 minutes to 4 hours after the dosing. One animal died at 6 hours after the dosing.

One mortality was observed at 300 mg/kg dose group, hence additional three female animals were treated with the higher dose of 2000 mg/kg of the test item (Step - I). Administration of the test item at 2000 mg/kg resulted in reduced locomotor activity, ataxic gait, tremors and convulsions with onset at 5 to 30 minutes after the dosing. Three animals died at 1 hour after the dosing.

All surviving animals from 300 mg/kg dose group exhibited normal body weight gain through the study period of 14 days. Gross pathological examination did not reveal any abnormalities in found dead animal and animals sacrificed terminally from 300 mg/kg dose group. Gross pathological examination revealed stomach distended with unabsorbed residual test item in found dead animals from 2000 mg/kg dose group.

Under the condition of the study, the acute oral LD50 value of the given test chemical was considered in between 300-2000 mg/kg body weight. Thus, it was concluded that the acute toxicity study of test chemical, when administered via oral route in Sprague Dawley rats falls into the “Category 4 (300 – ≤ 2000)” criteria of CLP.

 

The above study report is supported with another study mentioned in authoritative database for the given test chemical. The acute oral toxicity test was performed in mice at the test concentration of 360 mg/kg bw. Animals were observed for mortality. 50% mortality was observed in treated animals. Hence, the LD50 value was considered to be 360 mg/kg bw, when mice were treated with the given test chemical via oral route.

 

These studies are supported with the data available in secondary report for the test chemical. The acute oral toxicity study was carried out in male and female rats at the dose concentration range of 240-668 mg/kg bw.

Animals were observed for mortality and clinical signs. 50% mortality was observed in treated animals. Weakness, prostration, salivation, cyanosis, abnormal respiration and discoloured brown urine were observed.

Hence, the LD50 value was considered to be 476 (339-668)mg/kg in males and 336 (240-472) mg/kg in females, when male and female rats were treated with the given test chemical via oral route.

 

All the above studies are contradicted with the study mentioned in authoritative databases for the given test chemical. The acute oral toxicity test was performed by using the given test chemical in rats at the test concentration of 200 mg/kg bw. Animals were observed for mortality. 50% mortality was observed in treated animals. Hence, the LD50 value was considered to be 200 mg/kg bw, when rats were treated with the given test chemical via oral route.

The above study will not be considered for the classification as detailed information of the study is not available.

 

Thus, based on the above summarised key study on test chemical, all rats were died at 2000 mg/kg bw, hence the LD100 was considered to be 2000 mg/kg bw. Considering this value, the LD50 value can be expected to be 1000 mg/kg bw. Therefore, comparing this value with the criteria of CLP regulation, the given test chemical can be classified in “Category 4 (300 – ≤ 2000)” for acute oral toxicity.

Acute Inhalation Toxicity:

The acute inhalation toxicity study need not be conducted because exposure to humans via inhalation route is not likely taking into account due to the low vapour pressure of the test chemical, which is reported to be 0.002173155 Pa. Thus, exposure to inhalable dust, mist and vapour of the chemical is highly unlikely. Therefore this study is considered for waiver. 

Acute Dermal Toxicity:

In different studies, the given test chemical has been investigated for acute dermal toxicity to a greater or lesser extent. Often are the studies based on in-vivo experiments in rodents, i.e. most commonly in rats and guinea pigs for test chemical. The studies are summarized as below -

 

The reported key study was designed and conducted to determine the acute dermal toxicity profile of the given test chemical as per OECD Guideline 402 (Acute Dermal Toxicity) in Sprague Dawley rats.

The test item was applied to shorn skin of 5 male and 5 female animals at 2000 mg/kg body weight. Administration of the test item at 2000 mg/kg did not result in any skin reaction at the site of application during the study period of 14 days. Administration of the test item did not result in any signs of toxicity and mortality during the study period of 14 days.

Animals exhibited normal body weight gain through the study period of 14 days. Gross pathological examination did not reveal any abnormalities attributable to the treatment.

It was concluded that the acute dermal median lethal dose (LD50) of the given test chemical, when administered to male and female Sprague Dawley rats was considered to be >2000 mg/kg body weight. Thus, according to CLP criteria for acute toxicity rating for the chemicals, it infers that the given test chemical does not classify as an acute dermal toxicant. CLP Classification: “Not classified”.

 

Another study mentioned in authoritative database and secondary report was carried out to determine the acute dermal toxicity dose by using the given test chemical in guinea pigs at the dose concentration of 1000 mg/kg bw. Animals were observed for mortality. No mortality was observed in treated animals. Hence, the LD50 value was considered to be>1000 mg/kg bw, when guinea pigs were treated with the given test chemical by dermal application. From this study the exact value of LD50 is not calculated, hence the CLP classification cannot be decided.

 

Thus, based on the above summarised key study on test chemical, it can be concluded that LD50 value is >2000 mg/kg bw, for acute dermal toxicity. Thus, comparing this value with the criteria of CLP regulation, the given test chemical cannot be classified for acute dermal toxicity.

 

Justification for classification or non-classification

Based on the above studies on test chemical, it can be concluded that LD50 value is between 300-2000 mg/kg bw, for acute oral toxicity and LD50 value is >2000 mg/kg bw, for acute dermal toxicity. Thus, comparing this range and value with the criteria of CLP regulation, the given test chemical can be classified in “Category 4” for acute oral toxicity and cannot be classified for acute dermal toxicity. For acute inhalation toxicity wavier was added so, not possible to classify.