Diammonium [[N,N'-ethylenebis[N-(carboxymethyl)glycinato]](4-)-N,N',O,O',ON,ON']manganate(2-)

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

April-May 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well conducted study according to GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Diammonium [[N,N'-ethylenebis[N-(carboxymethyl)glycinato]](4-)-N,N',O,O',ON,ON']manganate(2-)

EC Number:

304-037-6

EC Name:

Diammonium [[N,N'-ethylenebis[N-(carboxymethyl)glycinato]](4-)-N,N',O,O',ON,ON']manganate(2-)

Cas Number:

94233-07-5

Molecular formula:

C10H12MnN2O8.2H4N

IUPAC Name:

Manganese(2+) ion diammonium 2-({2-[bis(carboxylatomethyl)amino]ethyl} (carboxylatomethyl)amino)acetate

Details on test material:

Chemical name: Ethylenediaminetetraacetic acid, manganese disodium complex
Purity: 92.3%
Batch no: CFC 9380
Expiry date: 31 August 2012

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, Sulzfeld, Germany
- Age at study initiation: 8 weeks
- Weight at study initiation: 269 g (males), 165 g (females)
- Fasting period before study: not applicable
- Housing: groups of 3, in macrolon cages, with bedding of wood shavings and strips of paper
- Diet (e.g. ad libitum): ad lib, except during exposure
- Water (e.g. ad libitum): ad lib, except during exposure
- Acclimation period: 15 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 45-65 with short excursions to higher levels during cleaning activities
- Air changes (per hr): ca. 10
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 22 April To: 6 May 2010

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose/head only

Vehicle:

other: water

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: nose only inhalation chamber / modification of ADG Developments Ltd.
- Exposure chamber volume: ca. 50 L
- Method of holding animals in test chamber: in polycarbonate restraining tubes
- Source and rate of air: dry compressed air
- Method of conditioning air: test substance was diluted in water; as such compressed air became humidified
- System of generating particulates/aerosols: atomizing a solution of 650 g EDTA-MnNa2 per L water
- Method of particle size determination: 1- stage cascade impactor
- Treatment of exhaust air: filtered
- Temperature, humidity, pressure in air chamber: 23.4 ± 0.2 (23.1-23.6) degrees C; 86 ± 1% (84.9-86.6%); slightly positive pressure in central exposure cylinder; slightly negative pressure in surrounding hood

TEST ATMOSPHERE
- Brief description of analytical method used: gravimetric analysis
- Samples taken from breathing zone: yes

VEHICLE
- Composition of vehicle (if applicable): water
- Concentration of test material in vehicle (if applicable): 650 g/L
- Justification of choice of vehicle: EDTA-MnNa2 is soluble in water; by atomizing a solution in water and evaporation of the water, respirable particles will be generated
- Lot/batch no. (if required): not applicable
- Purity: not applicable

TEST ATMOSPHERE (if not tabulated)
- Particle size distribution: measured once before exposure and twice during exposure
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.):
measurement 1: MMAD = 3.3 µm, GSD = 2.8
measurement 2: MMAD = 3.2 µm, GSD = 2.5
measurement 3: MMAD = 3.3 µm, GSD = 2.4

CLASS METHOD (if applicable)
- Rationale for the selection of the starting concentration: no acute toxicity expected; therefore starting concentration for aerosol used, viz. 5 mg/L.

Analytical verification of test atmosphere concentrations:

no

Remarks:

not needed in case of gravimetry

Duration of exposure:

4 h

Concentrations:

5.16 mg/L

No. of animals per sex per dose:

3

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: days 0 (prior to exposure), days 1, 3, 7 and 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Statistics:

Not needes; single exposure only

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 5.16 mg/L air

Based on:

test mat.

Exp. duration:

4 h

Mortality:

None

Clinical signs:

other: None during exposure. Shortly after exposure, slight sniffing was heard in one male and 2 females. A slightly soiled fur of the head was observed in all 3 females. No other abnormalities were seen.

Body weight:

On days 1 and 3, body weighth gain had slowed down. The overall body weight gain in 14 days was as expected for animals of the strain and age.

Gross pathology:

Petechiae were seen on both lobes of the thymus in one male. A petechia aws seen on one lung lobe of one female. These minor abnormalities were not considered to be related to the exposure.

Other findings:

None

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Remarks:

Migrated information

Conclusions:

Because the 4-h LC50 was > 5.16 mg/L and signs observed during and after exposure were very limited, EDTA-MnNa2 is not toxic after inhalation and classification is not needed.

Executive summary:

The aim of the present study was to investigate the acute inhalation toxicity of EDTAMnNa2 in rats. Therefore, three male and three female animals were exposed to a target concentration of 5 g/m3 during a single period of four hours. Animals were kept for an observation period of 14 days before sacrifice. To characterize the toxicity, the animals were observed during exposure, shortly after exposure and daily thereafter, body weight was measured before exposure and 1, 3, 7 and 14 days after exposure and the animals were examined for gross pathological changes at necropsy. The actual concentration of the test compound during exposure was 5.16 g/m3, based on gravimetric analysis of the test atmosphere. Measured mass median aerodynamic diameters were 3.2 and 3.3 µm and the distribution of particle sizes had a geometric standard deviation (gsd) of 2.5 and 2.4, respectively. No abnormalities were seen during exposure. Shortly after exposure, however, sniffing was heard in one male and two female animals and a soiled fur of the head was noticed in all three female animals. The next day, these or other clinical abnormalities were no longer seen. Body weight gain was as expected for animals of this age and strain on days 7 and 14, but was decreased on days 1 and 3. The minor macroscopic abnormalities found at necropsy (petechiae on the lobes of the thymus in one male animal and one petechia on one lung lobe in one female animal) were not considered to be related to the exposure. Mortality did not occur during the 14-day observation period after a 4 -hour exposure by inhalation to a concentration of 5.16 g/m3 of EDTA-MnNa2. It is therefore concluded that the 4-hour LC50 is above 5.16 g/m3 for male and female rats. According to the OECD Guideline for Testing of Chemicals 436 EDTA-MnNa2 should be classified as “unclassified”.