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Ecotoxicological information

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:
long-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Well performed study. Effect concentrations based on measured Se concentrations.

Data source

Reference
Reference Type:
other: manuscript
Title:
The Effects of Lesser Known Metals and One Organic to Fathead Minnows (Pimephales promelas) and Daphnia magna
Author:
Kimball G
Year:
1978
Bibliographic source:
Department of Entomology, Fisheries and Wildlife, University of Minnesota, Minneapolis, MN, 88pp

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 211 (Daphnia magna Reproduction Test)
GLP compliance:
not specified

Test material

Constituent 1
Chemical structure
Reference substance name:
Selenious acid
EC Number:
231-974-7
EC Name:
Selenious acid
Cas Number:
7783-00-8
Molecular formula:
H2O3Se
IUPAC Name:
selenous acid
Details on test material:
- Name of test material (as cited in study report): Selenious acid
- Molecular formula (if other than submission substance): H2SeO3
- Purity: reagent grade
- No further information on substance stated.

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
- Samples for metal analysis were drawn into 15 ml tubes and acidified with 1 drop of 1.0 N HNO3.
- Frequency: 3 times weekly

Test solutions

Vehicle:
no
Details on test solutions:
see test conditions

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
- Obtained from a commercially available source (Aquatic Life Company, Minneapolis, USA)
- Neonates, 12 ± 12 h old
- Animals were fed but no information on type and amount of food was stated.

Study design

Test type:
semi-static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
28 d

Test conditions

Hardness:
no data (hard water)
Test temperature:
20.4°C (average)
pH:
8.47 (average)

Dissolved oxygen:
7.43 mg/L (average)
Salinity:
not applicable
Nominal and measured concentrations:
Control + 0.07-0.12-0.19-0.30-0.48-0.92 mg/L.
Details on test conditions:
TEST SYSTEM
- Test vessel: 100 mL beaker, 50 mL fill volume
- Type of flow-through (e.g. peristaltic or proportional diluter): static renewal system
- Renewal rate of test solution (frequency/flow rate): three times a week
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10 replicates

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Hard water from a well tapping the Jordan sandstone stratum underlying the Minneapolis-St. Paul metropolitan area. Iron was catalytically removed (0.1 mg/L).
- Alkalinity: 210 mg CaCO3/L (average)

Results and discussion

Effect concentrationsopen allclose all
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
70 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
Se
Basis for effect:
reproduction
Duration:
28 d
Dose descriptor:
LOEC
Effect conc.:
120 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
Se
Basis for effect:
reproduction
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
190 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
Se
Basis for effect:
mortality
Duration:
28 d
Dose descriptor:
LOEC
Effect conc.:
300 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
Se
Basis for effect:
mortality
Details on results:
28 d LC50 of 240 µg Se/L based on mortality.
Reported statistics and error estimates:
The data was examined by one-way analysis of variance with treatment differences separated by Dunnett's procedure (one-tailed) at alpha=0.05.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
Klimisch 2 study on the chronic toxicity of selenium to Daphnia magna. The study was conducted according to a procedure similar to standard procedures for reproduction toxicity tests with cladocerans. The 28-day NOEC, LOEC and LC50 for mortality were 190, 300, and 240 µg Se/L, respectively. The 28-day NOEC and LOEC for reproduction were 70 and 120 µg Se/L, respectively.