lithium manganese iron phosphate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-04-01 to 2015-04-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2009-09-07

Deviations:

yes

Remarks:

GSD on particle size determinations were > 3 µm; rel. humidity was < 30% during exposure

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 2013-11-27

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Trimanganese bis(orthophosphate)

EC Number:

237-997-9

EC Name:

Trimanganese bis(orthophosphate)

Cas Number:

14154-09-7

Molecular formula:

H3O4P.3/2Mn

IUPAC Name:

manganese(II) phosphate

Test material form:

solid: particulate/powder

Details on test material:

- State of aggregation: pink solid powder

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature, protected from light

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: test item was desiccated 18 hours to facilitate the generation of a respirable aerosol.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, Barcelona, Spain
- Age at study initiation: 8 weeks
- Weight at study initiation: males: 260.06-279.34 g; females: 200.83-214.44 g
- Housing: 4 animals per cage before distribution, 3 animals per cage after distribution; bedding material: Capsumlab Lecho_10 (autoclavable)
- Diet: Global Diet 2914 C (Harlan Teklad, UK), ad libitum, except when animals were restrained in the exposure tubes
- Water: Tap water, ad libitum, except when animals were restrained in the exposure tubes
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature: 16.9-23.7 °C
- Relative humidity: 21 - 52 %
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation: dust

Type of inhalation exposure:

nose only

Vehicle:

clean air

Mass median aerodynamic diameter (MMAD):

1.4 µm

Remark on MMAD/GSD:

Mean Mass Median Aerodynamic Diameter (MMAD) of particle size distribution during exposure was calculated from two gravimetric measurements PSD #1 and PSD #2. Mean MMAD during exposure was 1.40 μm. This value is within the respirable range (1-4 μm) and appropriate for acute inhalation toxicity testing. Geometric Standard Deviation (GSD) on PSD #1 and PSD#2 were above the upper limit of 3 but considered acceptable as more than 63% of particles were below the upper limit of 4 μm in both cases (63.27% for PSD #1 and 66.7% for PSD#2) (see Table 1).

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Exposure chambers type EC-FPC-232 (anodised aluminium), equipped with glass exposure tubes were used.
- Exposure chamber volume: approximately 3 L
- Method of holding animals in test chamber: The animals were confined separately in restraint tubes which were positioned radially around the exposure chamber.
- Source and rate of air: Filtered air from a compressor. The exposure airflow rate was adjusted as appropriate before the start of the exposure using the pressure difference over a Venturi tube. The actual airflow rate was monitored hourly in each group during each exposure. The target range was 0.5-1.0 L/min through each inhalation tube.
- System of generating particulates/aerosols: A dust aerosol was generated from the desiccated test item using a Rotating Brush Generator PALAS RBG 2000. The dust was diluted with filtered air from a compressor and conveyed via glass tubing, from the generator to the exposure chamber. The flow rate through the exposure chamber was adjusted as necessary.
- Method of particle size determination: The particle size distribution was determined gravimetrically twice during exposure. The cumulative particle size distribution of the test aerosol was determined using a PIXE cascade impactor. The particle size distribution of the test item in the generated aerosol was measured by gravimetry analyzing the test item deposited on each stage of the cascade impactor.
The mass median aerodynamic diameter (MMAD) and the geometric standard deviation (GSD) were calculated on the basis of the results from the impactor, using Microsoft Excel® software (Microsoft Corporation, USA). The target ranges were 1 to 4 μm for the MMAD and 1.5 to 3 for the GSD.
- Temperature, humidity in air chamber: The temperature in the chamber was measured continuously during exposure using a thermohygrometer (Kimoth110, Kimo). The target range was 19-25°C. The results were reported approximately hourly from the start of the inhalation exposure.
The relative humidity in the chamber was measured continuously during exposure using a thermohygrometer (Kimoth110, Kimo). The target range was 30-70%. The results were reported approximately hourly from the start of the inhalation exposure.

TEST ATMOSPHERE
- Brief description of analytical method used: The test item usage was determined once per exposure by weighing the amount of the test item before and after exposure to determine the quantity of test item used. The weight used was then divided by the total air-flow volume to give the nominal concentration. These data were used for the purpose of monitoring the performance of the generation system.
Gravimetric determination of the aerosol concentration was performed at least once during each hour of exposure. Test aerosol samples were collected onto a Whatman filter (grade F319-04) using a filter sampling device. The sampling flow was similar to the air flow rate per exposure port. The duration of sampling was 5 minutes. The filters were weighed before and immediately after sampling using a calibrated balance. The gravimetric aerosol concentration was calculated from the amount of test item present on the filter and the sample volume.
- Samples taken from breathing zone: yes

CLASS METHOD (if applicable)
- Rationale for the selection of the starting concentration: The starting dose (approximately 5 mg/L air, during 4 hours) was selected as no toxic effects were expected based on the available data. This concentration was determined during technical trials (see 'Any other information on materials and methods incl. tables').

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

5.07 mg/L ± 0.56 (actual concentration)
2.0 mg/L (target concentration)

No. of animals per sex per dose:

3 males / 3 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were examined daily for mortality and morbidity. Clinical observations in response to treatment were performed on all animals hourly during exposure (only grossly abnormal signs), immediately and 1h after exposure, and once daily thereafter until the end of the observation period. Any visible clinical signs and discomfort were recorded. All animals were weighed on the day of treatment, just before starting the inhalation period (Day 1 of study), daily from Days 2 to 11, and immediately before sacrifice on Day 15 of study.
- Necropsy of survivors performed: yes

Statistics:

No statistical analysis was performed.

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 5.07 mg/L air (analytical)

Based on:

test mat.

Exp. duration:

4 h

Mortality:

All animals survived the scheduled observation period.

Clinical signs:

other: Dirty fur and chromorrhinorrhea were observed in all animals 1 hour after exposure. In addition, chromodacryorrhea (1 out of 3 males and in 1 out of 3 females) and mild piloerection (2 out of 3 males and in 2 out of 3 females) were recorded 1 hour after e

Body weight:

A significant body weight loss with respect to body weight at pretreatment (approximately 15% less in both sexes) was observed in all animals from day 1 of study to day 3 of study. Animals started to gain weight from day 4 of study but body weight at pretreatment was not recovered until day 10 of study in males and day 11 of study in females.
(See attached Appendix 2)

Gross pathology:

Lungs from 5 out of 6 animals did not show a normal appearance at the time of necropsy. The following macroscopic observations were recorded:
- White areas: 2 out of 6 animals (1 male and 1 female)
- Red spots: 2 out of 6 animals (1 male and 1 female)
- Black spots: 1 out of 6 animals (1 male)
- Pale appearance: 2 out of 6 animals (1 male and 1 female)
Lungs from affected animals were collected and preserved in fixative for further histopathological examination if considered necessary.
(See attached Appendix 3)

Any other information on results incl. tables

Test atmosphere conditions

Temperature during exposure was considered to be satisfactory and within target range (19-25ºC). Relative humidity was below target range (30-70%) (see section 13, deviation #3). Data are presented in the following table:

Recording time (h:min from exposure start)	Temperature (ºC)	Relative Humidity (%)
0:04	20.4	15.8
1:06	20.3	14.8
2:10	20.8	14.3
3:35	21.7	14.8
Mean	20.8	14.9
SD	0.64	0.63
N	4	4

Mean oxygen and carbon dioxide concentrations were 21.0 % and 0.04% respectively. These values are considered satisfactory for inhalation studies and within target range (at least 19% and below 1% respectively). Data are presented in the following table:

Recording time (h:min from exposure start)	Oxygen (%)	Carbon dioxide (%)
0:04	20.9	0.04
1:06	21.0	0.04
2:10	20.9	0.04
3:35	21.0	0.04
Mean	21.0	0.04
SD	0.06	0.00
N	4	4

 

Aerosol concentrations

The mean of the gravimetric concentrations during exposure was 5.07 mg/L air, as targeted. Data on aerosol concentrations are presented in the following table:

Group A (5.07 mg/L air). Day 1 of study
Sampling starting time (h:min from exposure start)	Sampling volume (L)	Amount of test item on the filter (mg)	Gravimetric aerosol concentration (mg/L)
0:06	5.54	26.47	4.78
0:36	5.57	31.27	5.62
1:01	5.57	31.85	5.72
1:12	5.57	29.57	5.31
1:45	5.57	30.70	5.52
2:11	5.56	26.44	4.76
2:31	4.43	19.45	4.39
2:40	5.56	24.69	4.44
3:08	5.56	24.67	4.44
3:39	5.56	26.88	4.84
3:49	5.56	32.81	5.91
MEAN	5.46	27.71	5.07
SD	0.34	3.98	0.56
N	11	11	11

 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

LC50 (male and female rats; 4 hours) > 5.07 mg/L(actual concentration)
According to the Regulation (EC) No 1272/2008 and subsequent adaptations, the substance is not acutely toxic via the inhalative route.