Hydrogen (glycinato-N,O)[sulphato(2-)-O,O']ferrate(1-)

Toxicity to aquatic plants other than algae

Administrative data

Endpoint:

toxicity to aquatic plants other than algae

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

publication

Title:

Toxicity Tests of Aquatic Pollutants by Using Common Duckweed

Author:

Wuncheng Wang

Year:

1986

Bibliographic source:

Environmental Pollution (Series B) 11 (1986) 1-14

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

- Principle of test: Duckweed stock was collected from a pond located inside the Illinois State Water Survey property during the spring of 1982. Twenty-four hours before the toxicity experiment was initiated, duckweed samples were selected for tests. A scoopful of duckweed from the stock was placed in a small tray containing cold tap water. The test specimens were selected from this tray and transferred to a second tray containing only deionized water. Unless specified, 20 colonies or 40 fronds of duckweed were used in this assay. The incubation time was 4 days, unless specified. Each experiment was conducted with 3-6 replicates. At the end of incubation, the number of fronds in each jar was counted with the aid of a magnifying glass. The increase of frond number was used to indicate duckweed growth and the difference between treated and control samples was used to indicate the toxic effect.
- Short description of test conditions: Temperature was maintained at 27 ° ± 2 °C. The pH of the solution was 7.5. For each toxicant, there were six concentration levels. The bioassay experiments were conducted in a series of 200 ml fruit jars. To each jar was added a toxicant and 200 ml of plant nutrient solution, the same as the algal nutrient solution suggested in Standard Methods. The illumination was provided by cool-white fluorescent light with an intensity of 6456 lux. Each jar was covered with a watch glass. Temperature was maintained at 27 ° ± 2 °C and the incubation time was 4 days, unless specified. Each experiment was conducted with 3-6 replicates.
- Parameters analysed / observed: growth rate

GLP compliance:

no

Remarks:

GLP compliance was not reported in this publication.

Test material

Test material information

Constituent 1

Reference substance name:

Iron dichloride

EC Number:

231-843-4

EC Name:

Iron dichloride

Cas Number:

7758-94-3

Molecular formula:

Cl2Fe

IUPAC Name:

dichloroiron

Test material form:

solid

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

not further details reported

Test organisms

Test organisms (species):

Lemna minor

Details on test organisms:

TEST ORGANISM
- Common name: duckweed
- Strain: Lemna minor
- Source (laboratory, culture collection): Duckweed stock was collected from a pond located inside the Illinois State Water Survey property during the spring of 1982.
- Age of inoculum (at test initiation):
- Method of cultivation: he stock was maintained in the laboratory in a polypropylene tray with 20 litre capacity. To the tray was added a small amount of sediment, collected from the same pond, 10 litres of pond water and 5 litres of cold tap water. The plants were illuminated with cool-white fluorescent lights. Every 3-4 days cold tap water was added to maintain the water level. Approximately twice a year, the stock was discarded and restocked with fresh duckweed.

ACCLIMATION
- Acclimation period: Twenty-four hours before the toxicity experiment was initiated, duckweed samples were selected for tests. A scoopful of duckweed from
the stock was placed in a small tray containing cold tap water. The test specimens were selected from this tray and transferred to a second tray containing only deionized water. The test specimens must appear healthy, with two fronds of approximately equal size per colony. Care was exercised so as not to injure the plant.
- Culturing media and conditions (same as test or not): For cultivation a small amount of sediment was added to the tray , collected from the same pond, 10 litres of pond water and 5 litres of cold tap water were used. The test was conducted in 200 ml of plant nutrient solution,the same as the algal nutrient solution suggested in Standard Methods

Study design

Test type:

not specified

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test conditions

Details on test conditions:

TEST SYSTEM
- Incubation chamber used: no
- Test vessel: 200 mL fruit jar
- No. of colonies per vessel: 20 colonies or 40 fronds per jar
- No. of vessels per concentration (replicates): 3-6
GROWTH MEDIUM
- Standard medium used: yes


OTHER TEST CONDITIONS
- Sterile test conditions: no
- Adjustment of pH: not reported
- Light intensity and quality: The illumination was provided by cool-white fluorescent light with an intensity of 6456 lux.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of frond number: manual counting

Results and discussion

Effect concentrations

Key result

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

3.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

frond number

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Conclusions:

In the present study of Wang (1986) 40 fronds of duckweed (Lemna minor) were exposed to 6 concentrations of FeCl3 each for 96h under static conditions. The number of fronds after incubation was compared to the respective negative (no treatment) control and the increase/decrease in frond number was used to calculate a LC50 value. The LC50 was 3.7 mg/L for Fe.