Manganese sulphide

Endpoint summary

Description of key information

Acute Oral Toxicity: Under the conditions of the study the acute oral LD50 was > 2 000 mg/kg bw.

 

Acute Inhalation Toxicity: Under the conditions of the study the acute inhalation LC50 was > 5.34 mg/L.

 

Acute Dermal Toxicity: MnS is not acutely toxic by the oral route (IUCLID ref: section 7.2.1). Due to its very low water solubility (IUCLID ref: section 4.8), dermal absorption is expected to be negligible.  Based  on the information on oral toxicity and the phys-chem properties of the substance – from a scientific evaluation, testing is not scientifically necessary in accordance with Annex XI  section 1.1.

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:

2009-10-21 to 2009-11-17

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study conducted to current accepted guideline.

Qualifier:

according to guideline

Guideline:

OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 bis (Acute Oral Toxicity - Fixed Dose Procedure)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories UK, Ltd. Bicester, Oxon, UK
- Age at study initiation: 8 to 12 weeks
- Weight at study initiation: The bodyweight variation did not exceed ± 20 % of the initial/mean bodyweight of any previously dosed animals.
- Fasting period before study: Overnight fasting prior to dosing, and 3 to 4 hours post dosing.
- Housing: Animals were housed in groups of up to four in suspended solid-floor polypropylene cages furnished with woodflakes.
- Diet : 2014 Teklad Global Rodent diet supplied by Harlan Teklad Blackthorn (Bicester, Oxon, UK) available ad libitum
- Water : Mains tap water available ad libitum
- Acclimation period: A minimum of 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 25 °C
- Humidity (%): 30 to 70 %
- Air changes (per hr): A minimum of 15 changes per hour
- Photoperiod (hrs dark / hrs light): 12 hour cycle

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 30 mg/mL at the 300 mg/kg dose level, 200 mg/mL at the 2000 mg/kg dose level
- Amount of vehicle (if gavage): 10 mL/kg
- Justification for choice of vehicle: suspend in distilled water

Doses:

2,000 mg/kg employed in the main test and 300 and 2,000 mg/kg in the sighting test.

No. of animals per sex per dose:

1 animal in each of the sighting dose levels, and 4 animals in the main test.

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Individual bodyweights were recorded on Day 0 (the day of dosing) and on Day 7 and 14.
Clinical observations were made at 30 minutes, then 1, 2 and 4 hours post dosing and then daily for fourteen days. Morbidity and mortality checks were made twice daily.
- Necropsy of survivors performed: yes, animals were killed by cervical dislocation at the end of the 14 day observation period
- Other examinations performed: All animals were subjected to gross necropsy. This consisted of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded.

Statistics:

Data evaluations included the relationship (if any were noted) between the animal's exposure to the test material and the incidence and severity of all abnormalities including behavioural and clinical observations, gross lesions, bodyweight changes, mortality and any other toxicological effects. If possible the signs of evident toxicity were also identified. Evident toxicity is defined as the toxic effects which are of a severity such that administration at the next highest level could result in mortality.

Using mortality data, an estimate of the acute oral median lethal dose (LD50) of the test material was made.

Preliminary study:

At both levels of dosing in the sighting study, all animals showed expected bodyweight gains over the observation period. No signs of systemic toxicity were noted, and at necropsy.

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: No signs of toxicity were noted at either 300 or 2000 mg/kg

Mortality:

No mortalities occurred during the study.

Clinical signs:

other: No signs of toxicity were noted during the study.

Gross pathology:

No macroscopic abnormalities were recorded at necropsy.

Other findings:

Not reported

Table 1: Clinical Observations and Mortality Data, Dose Level 300 mg/kg

 

Dose Level mg/kg	Animal No.	Effects Noted After Dosing (Hrs)				Effects Noted Post Dosing (Days)
		½	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
300	1-0 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

 

Table 2: Bodyweight and Bodyweight Changes, Dose Level 300 mg/kg

 

Dose Level mg/kg	Animal No.	Bodyweight (g) on Day			Bodyweight Gain (g) During Week
		0	7	14	1	2
300	1-0 Female	169	188	196	19	8

 

Table 3: Necropsy Findings, Dose level 300 mg/kg

 

Dose Level mg/kg	Animal No.	Time of Death	Macroscopic Observations
300	1-0 Female	Killed Day 14	No abnormalities detected

 

Table 4: Clinical Observations and Mortality Data, Dose Level 2,000 mg/kg

Dose Level mg/kg	Animal No.	Effects Noted After Dosing (Hrs)				Effects Noted Post Dosing (Days)
		½	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
2,000	2-0 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-0 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-1 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-2 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-3 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

 

Table 5: Bodyweight and Bodyweight Changes, Dose Level 2,000 mg/kg

 

Dose Level mg/kg	Animal No.	Bodyweight (g) on Day			Bodyweight Gain (g) During Week
		0	7	14	1	2
2,000	2-0 Female	190	198	212	8	14
	3 -0 Female	169	184	191	15	7
	3 -1 Female	166	175	181	9	6
	3 -2 Female	176	181	191	5	10
	3 -3 Female	198	205	211	7	6

 

Table 6: Necropsy Findings, Dose level 2,000 mg/kg

 

Dose Level mg/kg	Animal No.	Time of Death	Macroscopic Observations
2,000	2-0 Female	Killed Day 14	No abnormalities detected
	3-0 Female	Killed Day 14	No abnormalities detected
	3-1 Female	Killed Day 14	No abnormalities detected
	3-2 Female	Killed Day 14	No abnormalities detected
	3-3 Female	Killed Day 14	No abnormalities detected

Interpretation of results:

study cannot be used for classification

Conclusions:

MnS is not acutely toxic by the oral route.

Executive summary:

The acute toxicity of the test material via the oral route was assessed according to OECD Test Guideline 420 and EU Method B.1 bis and in compliance with GLP.

No mortalities occurred during the study and there were no signs of toxicity. All animals exhibited expected bodyweight gains during the course of the study. No macroscopic abnormalities were recorded at necropsy.

Under the conditions of the study the acute oral LD50 was > 2 000 mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

> 2 000 mg/kg bw

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29-12-2009 to 18-01-2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study conducted to current accepted guideline.

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Qualifier:

according to guideline

Guideline:

EU Method B.2 (Acute Toxicity (Inhalation))

GLP compliance:

yes (incl. QA statement)

Test type:

fixed concentration procedure

Species:

rat

Strain:

other: HsdHan: WIST

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories UK, Ltd. Bicester, Oxon, UK
- Age at study initiation: 8 to 12 weeks
- Weight at study initiation: The bodyweight varied between 200g to 357g*. * One male animal was slightly above the weight in the protocol (200g - 350g). This deviation was considered not to affect the purpose or validity of the study.
- Housing: Animals were housed in groups of five by sex in solid-floor polypropylene cages with stainless steel lids, furnished with softwood flakes.
- Diet : With the exception of the exposure period, free access to food (Harlan 2014 Rodent Diet, Harlan Laboratories UK Ltd, Oxon, UK) was allowed throughout the study.
- Water: With the exception of the exposure period, free access to mains drinking water was allowed throughout the study.
The diet, drinking water, bedding and chew blocks were routinely analysed and were considered not to contain any contaminants that could reasonably be expected to affect the purpose or integrity of the study.
- Acclimation period: A minimum of 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 25 °C
- Humidity (%): 30 to 70 %
- Air changes (per hr): A minimum of 15 changes per hour
- Photoperiod (hrs dark / hrs light): 12 hour cycle

Route of administration:

inhalation: dust

Type of inhalation exposure:

nose only

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Consisted of a SAG 410 Solid Aerosol Generator (TOPAS GmbH, Dresden, Germany) located adjacent to the exposure chamber

- Exposure chamber volume: The cylindrical exposure chamber had a volume of approximately 30 litres (dimensions: 28 cm diameter x 50 cm high).

- Method of holding animals in test chamber: 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 'O' ring. Only the nose of each animal was exposed to the test atmosphere

- Source and rate of air: The SAG 410 was connected to a meter compressed air supply.

- Method of conditioning air: Homogeneity of the test atmosphere within the chamber was not specifically determined during the study. Chambers of the same design (ADG Developments Ltd, Hitchin, Herts, UK) have been fully validated and shown to produce evenly distributed atmospheres in the animals breathing zone with a wide variety of test materials (Green J D et al, 1984).

- System of generating particulates/aerosols: A dust atmosphere was produced from the test material using a SAG 410 Solid Aerosol Generator (TOPAS GmbH, Dresden, Germany). A particulate separator was introduced before the aerosol entered the exposure chamber in order to remove large particles and thereby increase the inhalable portion of the generated aerosol.

- Method of particle size determination: The particle size of the generated atmosphere inside the exposure chamber was determined three times during the exposure period using a Marple Personal Cascade Impactor (Westech IS Ltd, Beds., UK). This device consisted of six impactor stages (9.0, 6.3, 4.0, 1.7, 0.81 and 0.30 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 material, 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 9.0, 6.3, 4.0, 1.7, 0.81 and 0.30 µm was calculated.

- Treatment of exhaust air: The extract from the exposure chamber passed through a 'scrubber' trap and was connected with a high efficiency filter to a metered exhaust system.

- Temperature, humidity, pressure in air chamber: The temperature and relative humidity inside the exposure chamber were measured by an electronic thermometer/ humidity meter (Hanna Instruments Ltd, Beds., UK) located in a vacant port in the animals' breathing zone of the chamber and recorded every thirty minutes throughout the four-hour exposure period. Oxygen levels within the exposure chamber were measured by an electronic oxygen analyser (Servomex (UK) Ltd, Crowborough, East Sussex) located in a vacant port in the animals' breathing zone of the chamber and recorded every thirty minutes throughout the four-hour exposure period. The test atmosphere was generated to contain at least 19% oxygen.


TEST ATMOSPHERE
- Samples taken from breathing zone: yes. The actual chamber concentration was measured at regular intervals during the exposure period. The gravimetric method used glass fibre filters placed in a filter holder. The holder was temporarily sealed in a vacant port in the exposure chamber in the animals' breathing zone and a suitable, known volume of exposure chamber air was drawn through the filter using a vacuum pump.



TEST ATMOSPHERE (if not tabulated)
- Particle size distribution: 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 4µm (considered to be the inhalable fraction) was determined. See table 2.

Duration of exposure:

4 h

Concentrations:

5.34 mg/L

No. of animals per sex per dose:

5 Male and 5 Female

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: All animals were observed for clinical signs at hourly intervals during exposure, immediately on removal from the restraining tubes at the end of exposure, one hour after termination of exposure and subsequently once daily for fourteen days. Any deaths or evidence of overt toxicity was recorded at each concentration. Individual bodyweights were recorded prior to treatment on the day of exposure and on Days 7 and 14 or at death.
- Necropsy of survivors performed: yes. At the end of the fourteen day observation period the surviving animals were killed by intravenous overdose of sodium pentobarbitone. All animals, including the one that died during the study, 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.

Statistics:

Data evaluations included the relationship, if any, between the animals' exposure to the test material and the incidence and severity of all abnormalities including behavioural and clinical observations, necropsy findings, bodyweight changes, mortality and any other toxicological effects.
Using the mortality data obtained, an estimate of the acute inhalation median lethal concentration (LC50) of the test material was made.

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 5.34 mg/L air (analytical)

Exp. duration:

4 h

Mortality:

One day after exposure a single female rat was found end.

Clinical signs:

other: Common abnormalities noted during the study included increased respiratory rate, hunched posture, pilo-erection, wet fur and generalised green fur staining by the test material. Surviving animals recovered to appear normal from Day 10 post-exposure. See t

Body weight:

All male animals and two females exhibited a bodyweight loss or reduced bodyweight gain during Week 1 but recovered to show normal development during Week 2. Normal bodyweight development was noted for all other animals the course of the study. See table 6

Gross pathology:

No macroscopic abnormalities were detected amongst animals that survived until Day 14 at necropsy. Abnormally dark lungs were noted in the animal that died during the course of the study at necropsy. See table 7.

Other findings:

Nott reported

Table 3: Mortality Data

Mean Achieved Atmosphere Concentration (mg/L)	Deaths
	Male	Female	Total
5.34	0/5	1/5	1/10

 

Key to Clinical Observations

Fs = generalised green fur staining by the test material 

H =hunched posture

P =pilo-erection

Ri =increased respiratory rate

Wf = wet fur

X =animal dead

 

Table 4: Individual Clinical Observations (Days of Exposure)

 

Mean Achieved Atmosphere Concentration (mg/L)	Animal Number and Sex	Hours During Exposure			On Removal From Chamber	One Hour Post-Exposure
		1	2	3
5.34	1 Male	Wf	Wf	Wf	Wf H P Ri Fs	Wf H P Ri Fs
	2 Male	Wf	Wf	Wf	Wf H P Ri Fs	Wf H P Ri Fs
	3 Male	Wf	Wf	Wf	Wf H P Ri Fs	Wf H P Ri Fs
	4 Male	Wf	Wf	Wf	Wf H P Ri Fs	Wf H P Ri Fs
	5 Male	Wf	Wf	Wf	Wf H P Ri Fs	Wf H P Ri Fs
	6 Male	Wf	Wf	Wf	Wf H P Ri Fs	Wf H P Ri Fs
	7 Male	Wf	Wf	Wf	Wf H P Ri Fs	Wf H P Ri Fs
	8 Male	Wf	Wf	Wf	Wf H P Ri Fs	Wf H P Ri Fs
	9 Male	Wf	Wf	Wf	Wf H P Ri Fs	Wf H P Ri Fs
	10 Male	Wf	Wf	Wf	Wf H P Ri Fs	Wf H P Ri Fs

 

Table 5: Individual Clinical Observations (Recovery Period)

 

Mean Achieved Atmosphere Concentration (mg/L)	Animal Number and Sex	Day Post Exposure
		1	2	3	4	5	6	7	8-14
5.34	1 Male	H P Ri Fs	H P Ri Fs	H P Ri	H Ri	Ri	Ri	Ri	RiUntil Day 9
	2 Male	H P Ri Fs	H P Ri Fs	H P Ri	H Ri	Ri	Ri	Ri	RiUntil Day 9
	3 Male	H P Ri Fs	H P Ri Fs	H P Ri	H Ri	Ri	Ri	Ri	RiUntil Day 9
	4 Male	H P Ri Fs	H P Ri Fs	H P Ri	H Ri	Ri	Ri	Ri	RiUntil Day 9
	5 Male	H P Ri Fs	H P Ri Fs	H P Ri	H Ri	Ri	Ri	Ri	RiUntil Day 9
	6 Male	H P Ri Fs	H P Ri Fs	H P Ri	H Ri	Ri	Ri	Ri	RiUntil Day 9
	7 Male	H P Ri Fs	H P Ri Fs	H P Ri	H Ri	Ri	Ri	Ri	RiUntil Day 9
	8 Male	X
	9 Male	H P Ri Fs	H P Ri Fs	H P Ri	H Ri	Ri	Ri	Ri	RiUntil Day 9
	10 Male	H P Ri Fs	H P Ri Fs	H P Ri	H Ri	Ri	Ri	Ri	RiUntil Day 9

 

Table 6: Individual Bodyweights

 

Mean Achieved Concentration (mg/L)	Animal Number and Sex	Bodyweight (g) on Day:				Increment (g) During Week:
		0	7	14	At Death	1	2
5.34	1 Male	333	329	358		-4	29
	2 Male	305	308	324		3	16
	3 Male	357	352	389		-5	37
	4 Male	331	327	355		-4	28
	5 Male	340	323	365		-17	42
	6 Male	218	223	233		5	10
	7 Male	241	246	246		5	0
	8 Male	221	-	-	206	-	-
	9 Male	241	237	243		-4	6
	10 Male	217	215	215		-2	0

 

Table 7: Individual Necropsy Findings:

 

Mean Achieved Concentration (mg/L)	Macroscopic Observations	Animal Number and Sex
		1 Male	2 Male	3 Male	4 Male	5 Male	6 Male	7 Male	8* Male	9 Male	10 Male
5.34	Lungs: Abnormally Dark								P
		N	N	N	N	N	N	N		N	N

P = Finding present

N= No abnormalities detected

* = Animal died during study

Table 8. Temperature and Relative Humidity in Exposure Chamber

 

Time (Minutes)	Chamber Temperature(°c) During Exposure	Chamber Relative Humidity (%) During Exposure
0	21	16
30	21	51
60	21	48
90	21	47
120	22	45
150	21	46
180	21	48
210	21	51
240	21	50

 

Table 9. Air Flow and Oxygen Concentration in Exposure Chamber

 

Time (Minutes)	Air Flow (L/min) During Exposure	Oxygen Concentration(%) During Exposure
-3	35	-
0	35	20.8
30	35	-
60	35	-
90	35	-
120	35	20.8
150	35	-
180	35	-
210	35	-
240	35	20.8

Interpretation of results:

study cannot be used for classification

Conclusions:

MnS is not acutely toxic by inhalation.

Executive summary:

The acute toxicity of the test material via the dermal route was assessed according to OECD Test Guideline 403 and EU Method B.2 and in compliance with GLP using a 4 h nose only exposure.

One day after exposure a single female rat was found end. 

Common abnormalities noted during the study included increased respiratory rate, hunched posture, pilo-erection, wet fur and generalised green fur staining by the test material. Surviving animals recovered to appear normal from Day 10 post-exposure.

All male animals and two females exhibited a bodyweight loss or reduced bodyweight gain during Week 1 but recovered to show normal development during Week 2. Normal bodyweight development was noted for all other animals the course of the study.

No macroscopic abnormalities were detected amongst animals that survived until Day 14 at necropsy. Abnormally dark lungs were noted in the animal that died during the course of the study at necropsy.

Under the conditions of the study the acute inhalation LC50 was > 5.34 mg/L.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC50

Value:

> 5.34 mg/L air

Physical form:

inhalation: dust / mist

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

MnS is not acutely toxic by the oral route (IUCLID ref: section 7.2.1). Due to its very low water solubility (IUCLID ref: section 4.8), dermal absorption is expected to be negligible. Based on the information on oral toxicity and the phys-chem properties of the substance – from a scientific evaluation, testing is not scientifically necessary in accordance with Annex XI section 1.1.

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Oral Route

The acute toxicity of the test material via the oral route was assessed according to OECD Test Guideline 420 and EU Method B.1 bis and in compliance with GLP.

No mortalities occurred during the study and there were no signs of toxicity. All animals exhibited expected bodyweight gains during the course of the study. No macroscopic abnormalities were recorded at necropsy.

Under the conditions of the study the acute oral LD50 was > 2 000 mg/kg bw.

Inhalation Route

The acute toxicity of the test material via the dermal route was assessed according to OECD Test Guideline 403 and EU Method B.2 and in compliance with GLP using a 4 h nose only exposure.

One day after exposure a single female rat was found end. 

Common abnormalities noted during the study included increased respiratory rate, hunched posture, pilo-erection, wet fur and generalised green fur staining by the test material. Surviving animals recovered to appear normal from Day 10 post-exposure.

All male animals and two females exhibited a bodyweight loss or reduced bodyweight gain during Week 1 but recovered to show normal development during Week 2. Normal bodyweight development was noted for all other animals the course of the study.

No macroscopic abnormalities were detected amongst animals that survived until Day 14 at necropsy. Abnormally dark lungs were noted in the animal that died during the course of the study at necropsy.

Under the conditions of the study the acute inhalation LC50 was > 5.34 mg/L.

Justification for classification or non-classification

MnS does not require classification for the oral route (LD50>2000 mg/kg) or the inhalation route (LC50>5mg/l). Classification via the dermal route is also not necessary based on lack of oral toxicity and poor water solubility of MnS, making it unlikely to absorb to any degree through the skin.