Diphenyl sulphide

Endpoint summary

Description of key information

Acute oral toxicity: 

The acute oral toxicity dose (LD50) was considered based on different studies conducted on rats for the test chemical. The LD50 value is between 300 to 2000 mg/kg bw, for acute oral toxicity. Thus, comparing this value with the criteria of CLP regulation, the given test chemical can be classified for acute oral toxicity class 4.

Acute Inhalation toxicity: 

According to column 2 of REACH Annex VIII, the acute inhalation toxicity study need not be conducted because exposure of humans via inhalation route is not likely taking into account the low vapour pressure of the substance Diphenyl sulphide (CAS No. 139-66-2), which is reported as 0.00241 mm Hg. Thus, exposure to inhalable dust, mist and vapour of the chemical Diphenyl sulphide (CAS No. 139-66-2) 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 and rabbits for the test chemical. The studies 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

Study period:

11-09-2017 to 17-11-2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Data is from study report

Qualifier:

according to guideline

Guideline:

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

Principles of method if other than guideline:

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

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: Young adult (8 to 10 weeks old) female rats were used.
- Weight at study initiation: The weight range of approximately 196.1 to 205.5 grams at initiation of dosing.
Body weights at the start : Female - Mean: 200.56 g (= 100 %);
Minimum : 196.1 g (- 2.22 %);
Maximum : 205.5 g (+ 2.47 %)
- 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 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): 20.0 to 22.0 degree centigrade.
- Humidity (%): 54.4% to 58.9%.
- 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: 11-09-2017 to 27-10-2017

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 300 mg/kg, 300 mg/kg, 2000 mg/kg
- Amount of vehicle (if gavage): 30mg/ml
- Justification for choice of vehicle:
- Lot/batch no. (if required): No data available
- Purity: No data available

MAXIMUM DOSE VOLUME APPLIED: 30 ml/kg body weight.

DOSAGE PREPARATION (if unusual): No data available

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: No data available

Doses:

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

No. of animals per sex per dose:

Group I: 3
Group I: 3
Group II: 3

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: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 perfonned 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:
No gross abnormalities were observed in animals sacrificed terminally hence, no histopathology was performed.

Statistics:

Not specified

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - < 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other:

Remarks:

Mortality observed

Mortality:

Group I: All animals survived through the study period of 14 days.
Group II: All animals survived through the study period of 14 days.
Group III: Three animals died at 6 hours after the dosing.

Clinical signs:

other: Step I Animals treated at the dose level of 300 mg/kg body weight did not result in any signs of toxicity during the study period of 14 days. Group I Step II Animals treated at the dose level of 300 mg/kg body weight did not result in any signs of toxici

Gross pathology:

Gross pathological examination did not reveal any abnormalities in animals from 300 mg/kg and 2000 mg/kg dose groups.

Other findings:

No data available

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	No clinical signs observed	3	1,2,3	Day 0 - Day 14	0/3

 

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	No clinical signs observed	3	4,5,6	Day 0 - Day 14	0/3

 

Group II :

Step No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal No	Period of signs in days From - to	Mortality
I	2000	Reduced locomotor activity	3	7,8,9	2 hr- 4hrs	3/3
		Ataxic gait	3	7,8,9	1 hr- 4hrs 2 hr- 4hrs
		Convulsions	2	7,9	4hrs

  

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	202.87	216.37	6.65	232.57	7.48	14.63
		± SD	2.81	3.76	0.48	4.66	0.39	0.93

 

 

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	200.30	214.30	6.99	231.40	7.98	15.52
		± SD	2.19	2.71	0.19	3.54	0.46	0.60

 

 

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	198.50	-	-	-	-	-
		± SD	3.49	-	-	-	-	-

 

 

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 - 3	TS	No abnormality detected

 

       

 Group I :

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

 

 Group II :

Step No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	2000	7 - 9	FD	No abnormality detected

               

TS = Terminal Sacrifice

FD = Found dead

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

Under the condition of the study, the acute oral LD50 of Diphenyl sulphide (CAS No. 139-66-2) was between 300 - 2000 mg/kg body weight. Thus, it was concluded that the acute toxicity study of Diphenyl sulphide (CAS No. 139-66-2), when administered via oral route in Sprague Dawley rats falls into the “Category- Acute toxicity class 4” criteria of CLP.

Executive summary:

The study was conducted to determine the acute oral toxicity profile of Diphenyl sulphide (CAS No. 139-66-2) 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 - l). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality 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 - ll).Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality after the dosing. Additional three female animals were treated with the higher dose of 2000 mg/kg of the test item (Step - 1). Administration of the test item at 2000 mg/kg resulted in reduced locomotor activity, ataxic gait and convulsions with onset at 1 to 4 hours after the dosing. Three animals died at 6 hours after the dosing. All animals from 300 mg/kg dose group survived and exhibited normal body weight gain through the study period of 14 days.Gross pathological examination did not reveal any abnormalities in animals from 300 mg/kg and 2000 mg/kg dose groups.

It was concluded that the acute toxicity study of Diphenyl sulphide (CAS No. 139-66-2) , when administered via oral route in Sprague Dawley rats falls into the “Category 4 (> 300-2000)” criteria of Globally Harmonized System (GHS).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

2 000 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:

the study does not need to be conducted because exposure of humans via inhalation is not likely taking into account the vapour pressure of the substance and/or the possibility of exposure to aerosols, particles or droplets of an inhalable size

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

Study period:

11-09-2017 to 28-12-2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Data is from study report

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Principles of method if other than guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

yes

Test type:

other: Acute dermal toxicity

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: Young adult (8 to 10 weeks old) female rats were used.
- Weight at study initiation: The weight range of approximately 216.0 to 238.9 grams at initiation of dosing.
Body weights at the start : Female - Mean: 227.78 g (= 100 %);
Minimum : 216.0 g (- 5.17 %);
Maximum : 238.9 g (+ 4.88 %)
- 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 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): 19.2 to 21.8 degree centigrade.
- Humidity (%): 56.0% to 59.1%.
- 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: 11-09-2017 to 28-12-2017

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: the trunk (dorsal surface and sides from scapular to pelvic area)
- % coverage: approximately 10% of the total body surface area
- Type of wrap if used: The test item was held in contact with the skin using a porous gauze dressing and non irritating tape around the animal to cover the exposure site. Elizabethan collar was placed on each animal for first 24 hours after application of the test item. These collars prevent ingestion of test item.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): The wrapping was removed and the test site wiped free of excess test item. Distilled water was used to remove residual test item.
- Time after start of exposure: 24 hours

Duration of exposure:

24 hrs

Doses:

Dose Range Finding Study:
Group I : 200 mg/kg
Group I : 1000 mg/kg
Group I : 2000 mg/kg
Main Study: Group II : 2000 mg/kg

No. of animals per sex per dose:

Dose Range Finding Study:
Group I : 200 mg/kg - 1
Group I : 1000 mg/kg - 1
Group I : 2000 mg/kg - 1
Main Study: Group II : 2000 mg/kg - 2

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Twice daily
- Necropsy of survivors performed: yes, 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).
- 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 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.
Histopathology:
No gross abnormalities were observed in animals sacrificed terminally hence, no histopathology was performed.

Statistics:

Not specified

Preliminary study:

Dose Finding Study: A single dose of 200 mg/kg body weight of the test item was administered to 1 female animal. No death or clinical signs of toxicity was observed during first 48 hours, hence, additional 1 female animal was administered at the dose of 1000 mg/kg body weight. Administration of 1000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours, hence, additional 1 female animal was administered at the dose of 2000 mg/kg body weight. Administration of 2000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours.

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

5 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other:

Remarks:

No mortality observed

Mortality:

Dose Range Finding Study: All animals survived through the study period of 14 days at 200 mg/kg, 1000 mg/kg and 2000 mg/kg body weight .
Main Study: Group II : All animals survived through the study period of 14 days.

Clinical signs:

other: Dose Range Finding Study: Animals treated at the dose level of 200 mg/kg, 1000 mg/kg and 2000 mg/kg body weight did not result in any signs of toxicity during the study period of 14 days. Main Study: Group II : Animals treated at the dose level of 2000 m

Gross pathology:

Gross pathological examination did not reveal any abnormalities in animals from 200 mg/kg, 1000 mg/kg and 2000 mg/kg dose groups from dose range finding study and main study sacrificed terminally.

Other findings:

Dose Range Finding Study: Group I : Animal treated at the dose level of 200 mg/kg body weight did not result in any skin reaction during the study period of 14 days.
Group I : Animal treated at the dose level of 1000 mg/kg body weight did not result in any skin reaction during the study period of 14 days.
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.
Main Study: Group II : Animals 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

 

Laboratory Test Item Code :TAS/122/056

Test System : Sprague Dawley Rat

Sex : Female

Dose Finding Study:

Group  No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	200	No clinical signs observed	1	1	Day 0 - Day 14	0/1

 

Group  No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
I	1000	No clinical signs observed	1	2	Day 0 - Day 14	0/1

 

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	1	3	Day 0 - Day 14	0/1

 

Main Study:

Group  No.	Dose mg/kg	Observed Signs	Total Number of Animals	Animal Nos.	Period of signs in days  From - to	Mortality
II	2000	No clinical signs observed	2	4, 5	Day 0 - Day 14	0/2

Table No. II 

Summary of Evaluation of Dermal Reaction

 

Laboratory Test Item Code :TAS/122/056

Test System : Sprague Dawley Rat

Sex : Female

Dose Finding Study:

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to
I	200	No dermal reaction observed	1	1	Day 0 - Day 14

 

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to
I	1000	No dermal reaction observed	1	2	Day 0 - Day 14

 

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to
I	2000	No dermal reaction observed	1	3	Day 0 - Day 14

 

Main Study:

Group  No.	Dose mg/kg	Dermal Reaction	Total Number of Animals	Animal Nos.	Period of signs in days  From - to
II	2000	No dermal reaction observed	2	4, 5	Day 0 - Day 14

 

Table No.III

Mean Body Weight and Percent Body Weight Gain (g)

 

Laboratory Test Item Code :TAS/122/056

Test System : Sprague Dawley Rat

Sex : Female

Dose Finding Study:

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	200	Mean	222.6	236.2	6.11	248.4	5.17	11.59
		± SD	-	-	-	-	-	-

 

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	1000	Mean	216.0	228.2	5.65	241.8	5.96	11.94
		± SD	-	-	-	-	-	-

 

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	230.6	242.5	5.16	250.5	3.30	8.63
		± SD	-	-	-	-	-	-

Main Study:

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
II	2000	Mean	234.85	246.75	5.07	257.45	4.34	9.63
		± SD	5.73	5.16	0.36	4.17	0.49	0.90

Table No.IV

Summary of Gross Pathological Findings

 

Laboratory Test Item Code :TAS/122/056

Test System : Sprague Dawley Rat

Sex : Female

Dose Finding Study:

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	200	1	TS	No abnormality detected

 

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	1000	2	TS	No abnormality detected

 

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
I	2000	3	TS	No abnormality detected

 

                    Main Study:

Group No.	Dose mg/kg	Animal Numbers	Animal Fate	Gross Pathological Findings
II	2000	4, 5	TS	No abnormality detected

 

                     TS = Terminal Sacrifice

Interpretation of results:

other: Not cassified

Conclusions:

It was concluded that the acute dermal median lethal dose (LD50) of Diphenyl sulphide, when administered to 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 Diphenyl sulphide (CAS No. 139 -66 -2) as per OECD Guideline 402 (Acute Dermal Toxicity) in Sprague Dawley rats.

In the dose range finding study a single dose of 200 mg/kg body weight of the test item was administered to 1 female animal. No death or clinical signs of toxicity was observed during first 48 hours, hence, additional 1 female animal was administered with the dose of 1000 mg/kg body weight. Administration of 1000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours, hence, additional 1 female animal was administered at the dose of 2000 mg/kg body weight. Administration of 2000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours.

As the dose range finding study revealed no mortality or clinical signs at the maximum dose of 2000 mg/kg, the main study was initiated with two additional animals. The animals were administered with a dose of 2000 mg/kg body weight in sequential manner at 48 hours intervals.

Animals from dose range finding study treated at the dose levels of 200 mg/kg, 1000 mg/kg and 2000 mg/kg and animals from main study treated at the dose level of 2000 mg/kg exhibited normal body weight gain and revealed no clinical signs of toxicity or mortality during 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 Diphenyl sulphide (CAS No. 139 -66 -2), when administered to 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 Diphenyl sulphide (CAS No. 139 -66 -2) 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, Diphenyl sulphide (CAS No. 139-66-2) 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 Diphenyl sulphide. The studies are summarized as below –

The study was conducted to determine the acute oral toxicity profile of Diphenyl sulphide (CAS No. 139-66-2) 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 - l). Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality 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 - ll).Administration of the test item at 300 mg/kg did not result in any signs of toxicity and mortality after the dosing. Additional three female animals were treated with the higher dose of 2000 mg/kg of the test item (Step - 1). Administration of the test item at 2000 mg/kg resulted in reduced locomotor activity, ataxic gait and convulsions with onset at 1 to 4 hours after the dosing. Three animals died at 6 hours after the dosing. All animals from 300 mg/kg dose group survived and exhibited normal body weight gain through the study period of 14 days. Gross pathological examination did not reveal any abnormalities in animals from 300 mg/kg and 2000 mg/kg dose groups.It was concluded that the acute toxicity study of Diphenyl sulphide (CAS No. 139-66-2) , when administered via oral route in Sprague Dawley rats falls into the “Category 4 (> 300-2000)” criteria of Globally Harmonized System (GHS).

In another study, the acute oral range-finding toxicity LD50 was concluded on Carworth-Wistar male rats to evaluate the toxic nature of Diphenyl sulphide/Phenyl sulfide (CAS No. 139-66-2) at a concentration of 0.38 - 0.65 ml/kg (424.84- 726.7 mg/Kg). LD50 value and its fiducial range were estimated by the method of Thompson using the Tables of Weil. 50% mortality was observed at 490 mg/kg bw in treated rats. Thus, it was concluded that the acute toxicity study of Diphenyl sulphide, when administered via oral route in Carworth-Wistar rats falls into the “Category 4” criteria of CLP.

The above study is supported this study report. For the test substance Diphenyl sulphide (DSP) (CAS No. 139-66-2) on Kunming female mice at the concentration range of 1,262- 2,044 mg/Kg bw. The test material (Purity: >99 %) was dissolved in corn oil and administered via oral gavage route as 0.1–0.2 ml/100 gm. 10 mice/dose group and control animals were taken for the study. Animals were observed for mortality and clinical signs over 14 days. Necropsy was performed. Statistical analysis was performed by using SPSS Version 12.0 for Windows. For all the parameters analyzed, the differences between the control and experimental groups were analyzed using one-way analysis of variance, and Tukey’s test. Values of p<0.05 were considered significant, and values of p<0.01 were accepted as having high statistical significance. 50% Mortality was observed in treated mice. Clinical signs such as, Asthenia, piloerection, ataxia, anorexia and syncope were observed. Weight loss was observed. Focal red areas on the gastric wall and Hepatomegaly were also observed. Epiphora and tear overflow after administering was observed. This indicated these toxicants or metabolites may cause eye damage. In Organ weight examination: Increased relative liver weights and decreased relative kidney weights were observed; and In Histopathology: Swollen cells, inflammation, vacuolization and necrosis of liver were observed. Hence, LD50 value for the test compound Diphenyl sulphide was considered to be 1,605 mg/kg with a 95% confidence interval of 1,262–2,044 mg/kg in Kunming female mice. Thus, it was concluded that the acute toxicity study of Diphenyl sulphide, when administered via oral route in Kunming female mice falls into the “Category 4” criteria of CLP.

In another study based on the QSAR prediction done using the Danish (Q)SAR Database, the acute oral toxicity was estimated for the Diphenyl sulphide (139-66-2). The LD50 was estimated to be 1300 mg/kg bw with Reliability Index 0.62 (0.5-0.75 = moderate prediction quality), when rats were treated with Diphenyl sulphide orally.

This studies were further supported based on QSAR prediction done using the Danish (Q)SAR Database,the acute oral toxicity was estimated for the Diphenyl sulphide (139-66-2). The LD50 was estimated to be 1400 mg/kg bw with Reliability Index 0.56 (0.5-0.75 = moderate prediction quality), when mice were treated with Diphenyl sulphide orally.

Thus, based on the above studies on Diphenyl sulphide (CAS No. 139-66-2), it can be concluded that LD50 value is between 300-2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, Diphenyl sulphide (CAS No. 139-66-2) can be classified as “Category 4” for acute oral toxicity.

Acute Inhalation toxicity: 

According to column 2 of REACH Annex VIII, the acute inhalation toxicity study need not be conducted because exposure of humans via inhalation route is not likely taking into account the low vapour pressure of the substance Diphenyl sulphide (CAS No. 139-66-2), which is reported as 0.00241 mm Hg. Thus, exposure to inhalable dust, mist and vapour of the chemical Diphenyl sulphide (CAS No. 139-66-2) is highly unlikely. Therefore this study is considered for waiver.

Acute Dermal toxicity:

In different studies, Diphenyl sulphide (CAS No. 139-66-2) 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 rabbits and rats for Diphenyl sulphide along with the study available on the structurally similar read across substances Diphenyl acetonitrile (CAS No. 86-29-3) and 4,4'-Thiodiphenol (2664-63-3). The studies are summarized as below –

The reported study was designed and conducted to determine the acute dermal toxicity profile of Diphenyl sulphide (CAS No. 139 -66 -2) as per OECD Guideline 402 (Acute Dermal Toxicity) in Sprague Dawley rats. In the dose range finding study a single dose of 200 mg/kg body weight of the test item was administered to 1 female animal. No death or clinical signs of toxicity was observed during first 48 hours, hence, additional 1 female animal was administered with the dose of 1000 mg/kg body weight. Administration of 1000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours, hence, additional 1 female animal was administered at the dose of 2000 mg/kg body weight. Administration of 2000 mg/kg body weight did not reveal any clinical signs of toxicity or death during first 48 hours. As the dose range finding study revealed no mortality or clinical signs at the maximum dose of 2000 mg/kg, the main study was initiated with two additional animals. The animals were administered with a dose of 2000 mg/kg body weight in sequential manner at 48 hours intervals. Animals from dose range finding study treated at the dose levels of 200 mg/kg, 1000 mg/kg and 2000 mg/kg and animals from main study treated at the dose level of 2000 mg/kg exhibited normal body weight gain and revealed no clinical signs of toxicity or mortality during 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 Diphenyl sulphide (CAS No. 139 -66 -2), when administered to 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 Diphenyl sulphide (CAS No. 139 -66 -2) does not classify as an acute dermal toxicant. CLP Classification: “Not classified”.

In another study, the acute dermal toxicity study was conducted in 4 Albino New Zealand male rabbits for the test material Diphenyl sulphide/Phenyl Sulfide (CAS No. 139-66-2) at a dose level of 11.3 mL/kg (11300 mg/kg bw) for 24 hours of exposure period.The fur is removed from the entire trunk by clipping, and the dose is retained beneath an impervious plastic film. Dosages greater than 20 ml/kg cannot be retained in contact with the skin. The rabbits were observed for mortality for 14 days.LD50 value and its fiducial range were estimated by the method of Thompson using the Tables of Weil. 50% mortality was observed in treated rabbits at 11300 mg/kg bw. Therefore, LD50 value was considered to be 11300 mg/kg bw, when Albino New Zealand male rabbits were treated with Diphenyl sulphide for 24 hours by dermal application to the clipped skin.

This study is supported by the structurally similar read across substance Diphenyl acetonitrile (CAS No. 86-29-3) 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 Diphenyl acetonitrile (CAS No. 86-29-3), when administered to male and female Sprague Dawley rats was found to be >2000 mg/kg body weight. Thus, according to CLP criteria for acute toxicity rating for the chemicals, it infers that Diphenyl acetonitrile (CAS No. 86-29-3) does not classify as an acute dermal toxicant. CLP Classification: “Not classified”.

The above study is further supported as: for the structurally similar read across substance 4,4'-Thiodiphenol (2664-63-3) in rabbits at the concentration of 10250 mg/kg bw. No Mortality was observed in treated rabbits at 10250mg/kg bw. Hence, LD50 value was considered to be >10250 mg/kg bw, when rabbits were treated with4,4'-Thiodiphenol by dermal application to skin.

Thus, based on the above studies on Diphenyl sulphide (CAS No. 139-66-2) and it’s read across substances, it can be concluded that LD50 value is >2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, Diphenyl sulphide cannot be classified for acute dermal toxicity.

Justification for classification or non-classification

Based on the above studies on Diphenyl sulphide (CAS No. 139-66-2) and it’s read across substances, it can be concluded that LD50 value is between 300-2000 mg/kg bw for acute oral and LD50 value is >2000 mg/kg bw for acute dermal toxicity. Thus, comparing this value with the criteria of CLP regulation, Diphenyl sulphide can be classified as “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.