Manganese dichloride

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Meets generally accepted scientific standards, well documented and acceptable for assessment.

Data source

Reference

Reference Type:

publication

Title:

Effects of Various Metals on Survival, Growth, Reproduction, and Metabolism of Daphnia magna.

Author:

Biesinger KE & Christensen GM

Year:

1972

Bibliographic source:

Journal of the Fisheries Research Board of Canada.29:1691-1700.

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

The toxicity of manganese chloride to Daphnia magna was evaluated on the basis of a 48- hr 50% lethal concentration (LC50).

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Manganese dichloride

EC Number:

231-869-6

EC Name:

Manganese dichloride

Cas Number:

7773-01-5

Molecular formula:

Cl2Mn

IUPAC Name:

manganese(2+) dichloride

Details on test material:

- Name of test material: Manganese
- Molecular formula: MnCl2.4H2O

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Analytical measurement in test containers were made at the time of addition of the test substance.

Test solutions

Details on test solutions:

American Chemical Society reagent-grade chemicals were used for the test(MnCl2.4H2O). Fresh stock solutions were prepared in lake water for each experiment.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Source: University of Michigan (Daphnia magna from a laboratory clone originally obtained from the university of Michigan were used)
- Age at study initiation (mean and range, SD): 12±12 hr old
- Feeding during test
- Food type: The food suspension was prepared by adding 0.5 g of powdered dried grass and 10 g of enriched trout-fry granules to 250 ml of Lake Superior water and mixing vigorously in a blender for 5 min. The suspension was then strained through #20 bolting cloth. The blender was rinsed with an additional 50 ml of lake water, and the rinse water was added to the suspension. In addition to the food mixture, the daphnids obtained some nutrients from bacteria, algae, and detritus in the water.
- Amount: 1 ml/ liter
- Frequency: Twice weekly for rearing and once weekly for testing.

Study design

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Post exposure observation period:

Not reported

Test conditions

Hardness:

45, 300 µg/ liter (Mean) - See Table 1.

Test temperature:

Not reported

pH:

7.74 (Mean) -See Table 1.

Dissolved oxygen:

Dissolved oxygen concentrations in test containers were near saturation at all times. At dawn, before the light comes on, the concentration was ~ 9 mg/ liter.

Salinity:

Not reported

Nominal and measured concentrations:

Nominal concentrations - 5,000 & 10,000
Measured Concentrations - 4,800 & 9,400 (Mean). See Table 2.

Details on test conditions:

TEST SYSTEM
- Test vessel: Test chambers
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates):2
- No. of vessels per control (replicates): 2


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Lake Superior water

OTHER TEST CONDITIONS
- Photoperiod: An automatically controlled 16-hr photoperiod was used.
- Light intensity: ~ 115 ft-c


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Tests were run both with and without food additions as the food changed the toxicity values. Complete immobilisation or death was the endpoint.

Reference substance (positive control):

not specified

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

9.8 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

dissolved

Basis for effect:

other: as Mn2+

Remarks on result:

other: Without Food

Details on results:

Not reported

Reported statistics and error estimates:

Results were statistically evaluated with the method of Litchfield and Wilcoxon (1949) for establishing approximations of the 95% confidence limits for survival. The terminology recommended by Sprague (1969), lethal concentration(LC), was used for survival and, as given here, represents an interpolation from three or more partial-effect concentrations

Any other information on results incl. tables

Table 3. Acute (48-hr) toxicities of various metal ions (µg/liter) to Daphnia magna in water.

 

	Acute test: LC50		Chronic test: 16% reproductive impairment (with food)
Metal ion	Without food	With food
Manganese	9800	-	4100

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Conclusions:

The 48-hr 50% lethal concentration(LC50) to Daphnia magna was 9.8 mg Mn/L without the addition of food.