Manganese dinitrate

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and conducted to current guideline. In addition, manganese nitrate has been shown to be stable at the concentration and pH used in the study (refer to IUCLID section 5.6) supporting the high reliability of the result.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

manganese dinitrate tetrahydrate

IUPAC Name:

manganese dinitrate tetrahydrate

Details on test material:

- Molecular formula (if other than submission substance): Mn(NO3)2.4H20
- Physical state: solid
- Stability under test conditions: Stable
- Storage condition of test material: approximately 4°C over silica gel in the dark

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 100 mg/l
- Sampling method: The test samples were analysed following addition of nitric acid (1 ml per 20 ml of sample or equivalent).
- Sample storage conditions before analysis: not stored

Test solutions

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: the test item was dissolved directly in reconstituted water. An amount of test item (100 mg) was dissolved in reconstituted water and the volume adjusted to 1 litre to give the 100 mg/l test concentration from which serial dilutions were prepared in reconstituted water to give the remainder of the test series of 10, 1.0, 0.10 and 0.010 mg/l. The prepared concentration was inverted several times to ensure adequate mixing and homogeneity
- Controls: The control group was maintained under identical conditions but not exposed to the test item
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no undissolved material was observed.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: 1st instar
- Source: in-house laboratory cultures
- Age at study initiation : less than 24 hours old
- Feeding during test: no

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Hardness:

250 mg/l as CaCO3

Test temperature:

20°C

pH:

7.7-7.8

Dissolved oxygen:

8.7-9.0 mg/l

Salinity:

Not reported

Nominal and measured concentrations:

Nominal
Sample Concentration Nominal Concentration Concentration of Manganese Expressed as a Percentage
(mg/l) of manganese Found (mg/l) of the Manganese Concentration (%)

0 Hours Control R1 - R4 - 100 R1 - R2 22 21.4 97
100 R3 - R4 22 21.4 97
48 Hours Control R1 - R4 - 100 R1 - R2 22 20.2 92
100 R3 - R4 22 20.8 94

Details on test conditions:

TEST SYSTEM
- Test vessel: glass jars
- Type : closed
- Material, size, headspace, fill volume: 250 ml
- Aeration: none
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: The dilution water was reconstituted water prepared by addition of an aliquot(25 ml) of the following solutions to each litre of deionised water with a conductivity of < 5µS cm-1:
a) CaCl2.2H2O 11.76 g/l
b) MgSO4.7H2O 4.93 g/l
c) NaHCO3 2.59 g/l
d) KCl 0.23 g/l

- Intervals of water quality measurement: 0, 24 and 48 hrs

OTHER TEST CONDITIONS
- Adjustment of pH: The reconstituted water had a pH of 7.8 ± 0.2 adjusted (if necessary) with NaOH or HCl initially, but not during the test.
- Photoperiod: 16 hours light and 8 hours darkness cycle with 20 minute dawn and dusk transition periods.


EFFECT PARAMETERS MEASURED : Immobilisaton based on being unable to swim for approximately 15 seconds after gentle agitation.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: not applicable as limit test at 100 mg/l
- Range finding study: yes
- Test concentrations in range-finding study: 100, 10, 1.0, 0.10 and 0.010 mg/l
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

manganese was measured by ICP-MS and concentration related back to test material.

Basis for effect:

mobility

Remarks:

If daphnia did not swim for approximately 15 seconds after gentle agitation.

Details on results:

- Behavioural abnormalities: none
- Mortality of control: none
- Other adverse effects control: none
- Abnormal responses: none
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: none
- Effect concentrations exceeding solubility of substance in test medium: no

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- EC50: 0.77 mg/l

Reported statistics and error estimates:

An estimate of the EC50 values was given by inspection of the immobilisation data.

For the positive control The EC50 values and associated confidence limits at 24 hours and the slope of the response curve and standard error were calculated by the maximum-likelihood probit method (Finney 1971) using the ToxCalc computer software package (ToxCalc 1999). The EC50 value and associated confidence limits at 48 hours were calculated by the trimmed Spearman-Karber method (Hamilton et al 1977) using ToxCalc computer software package (ToxCalc 1999).
Probit analysis is used where two or more partial responses to exposure are shown.
When only one potential response is shown the trimmed Spearman-Karber method is appropriate.

Any other information on results incl. tables

Cumulative Immobilisation Data in the Definitive Test

Nominal Concentration (mg/l)		Cumulative Immobilised Daphnia (Initial Population: 5 Per Replicate)
		24 Hours			48 Hours
		No. Per Replicate	Total	%	No. Per Replicate	Total	%
Control	R1	0	0	0	0	0	0
	R2	0			0
	R3	0			0
	R4	0			0
100	R1	0	0	0	0	0	0
	R2	0			0
	R3	0			0
	R4	0			0

R₁– R₄= Replicates 1 to 4

Cumulative Immobilisation Data in the Positive Control

Nominal Concentration (mg/l)	Cumulative Immobilised Daphnia (Initial Population: 10 Per Replicate)
	24 Hours				48 Hours
	R1	R2	Total	%	R1	R2	Total	%
Control	0	0	0	0	0	0	0	0
0.32	0	0	0	0	0	0	0	0
0.56	1	1	2	10	3	2	5	25
1.0	7	7	14	70	10	10	20	100
1.8	10	10	20	100	10	10	20	100
3.2	10	10	20	100	10	10	20	100

Verification of test concentrations

Sample	Nominal Concentration (mg/l)	Nominal Concentration of manganese	Concentration of Manganese Found (mg/l)	Expressed as a Percentage of the Manganese Concentration (%)
0 Hours	Control R1- R4	-	<LOQ	-
	100 R1- R2	22	21.4	97
	100 R3- R4	22	21.4	97
48 Hours	Control R1- R4	-	<LOQ	-
	100 R1- R2	22	20.2	92
	100 R3- R4	22	20.8	94

LOQ = Limit of quantitation

R₁– R₄= Replicates 1 to 4

Physico-Chemical Measurements

Nominal Concentration (mg/l)		0 Hours				24 Hours	48 Hours
		pH	mg O2/l	%*	T°C	TºC	pH	mg O2/l	%*	T°C
Control	R1	8.0	9.0	99	20	20	8.0	8.8	97	20
	R2	8.0	9.0	99	20	20	8.0	8.7	96	20
	R3	8.0	9.0	99	20	20	8.0	8.8	97	20
	R4	8.0	9.0	99	20	20	8.0	8.7	96	20
100	R1	7.8	9.0	99	20	20	7.7	8.7	96	20
	R2	7.8	9.0	99	20	20	7.7	8.7	96	20
	R3	7.8	9.0	99	20	20	7.8	8.7	96	20
	R4	7.8	9.0	99	20	20	7.8	8.7	96	20

*= Dissolved oxygen concentration expressed as a percentage of Air Saturation Value

R₁– R₄= Replicates 1 to 4

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Manganese dinitrate tetrahydrate is not acutely harmful to daphnia magna, with an EC(50) > 100 mg/l.