Non-graphitic carbon fibre

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-11-13 to 2013-02-22

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

carbon

EC Number:

701-026-1

Cas Number:

7440-44-0

Molecular formula:

C up to (C80N5H16O)n

IUPAC Name:

carbon

Test material form:

solid: fibres

Details on test material:

- milled carbonised PAN based fibre (Sigrafil C30 M150 UNS)
- for further details on the test material, see section 1.4, endpoint "Non-graphitic carbon fibre (carbonised PAN based fibre, milled)", attached document "Analytics_milled_carbonised_PAN_based_fibre.pdf"

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

Preparation and application of test solution (especially for difficult test substances)
- Method: water accomodated fraction (WAF according to OECD 23)
- Eluate: not applicable
- Differential loading: no
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): not applicable
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): not applicable
- Evidence of undissolved material (e.g. precipitate, surface film, etc): yes

Test organisms

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Common name: Pseudokirchneriella subcapitata, Chlorophycea, Chlorophyta
- Strain: 61.81 SAG
- Source (laboratory, culture collection): SAG, Culture Collection of Algae at Pflanzenphysiologisches Institut of the University at Göttingen, Germany
- Method of cultivation: stock culture maintained according to OECD 201

ACCLIMATION
- Acclimation period: 3 d
- Culturing media and conditions (same as test or not): same as test medium
- Any deformed or abnormal cells observed: no

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Post exposure observation period:

not applicable

Test conditions

Hardness:

growth medium according to OECD 201

Test temperature:

21.5 - 22.5 °C

pH:

7.5 - 8.0

Salinity:

growth medium according to OECD 201

Nominal and measured concentrations:

water accomodated fraction (WAF according to OECD 23), nominal loading: 100 mg test item/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 mL conical glass flasks
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: glass, 100 mL
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): not applicable
- Initial cells density: 10.000 cells/mL
- Control end cells density: 138.1 x 10^4 cells/ mL
- No. of organisms per vessel: not applicable
- No. of vessels per concentration (replicates): 8
- No. of vessels per control (replicates): 8
- No. of vessels per vehicle control (replicates): not applicable

GROWTH MEDIUM
- Standard medium used: yes
- Detailed composition if non-standard medium was used: not applicable

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: OECD medium
- Culture medium different from test medium: no
- Intervals of water quality measurement: not reported

OTHER TEST CONDITIONS
- Sterile test conditions: yes/no
- Adjustment of pH: yes
- Photoperiod: continous
- Light intensity and quality: 4440 - 8880 lux (60 - 120 µE*m-2*s-1)
- Salinity (for marine algae): not applicable

EFFECT PARAMETERS MEASURED (with observation intervals if applicable):
- Determination of cell concentrations: electronic particle counter
- Chlorophyll measurement: no

TEST CONCENTRATIONS
- Spacing factor for test concentrations: limit test
- Range finding study: yes, nominal loadings: 1 mg/L, 10 mgl/L, 100 mg/L
- Test concentration: 100 mg/L
- Results used to determine the conditions for the definitive study: yield (cell number), growth rate

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EL10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limit

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limit

Effect concentrations 3

Duration:

72 h

Dose descriptor:

other: NOEL

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limit

Effect concentrations 4

Duration:

72 h

Dose descriptor:

EL10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Remarks on result:

other: 95% confidence limit

Effect concentrations 5

Duration:

72 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Remarks on result:

other: 95% confidence limit

Effect concentrations 6

Duration:

72

Dose descriptor:

other: NOEL

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Remarks on result:

other: 95% confidence limit

Details on results:

- Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test): done, but no abnormalities found
- Unusual cell shape: no
- Colour differences: no
- Flocculation: no
- Adherence to test vessels: no
- Aggregation of algal cells: no
- Other: some debris found
- Any stimulation of growth found in any treatment: no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: not applicable (a water accomodated fraction (WAF according to OECD 23) was prepared
- Effect concentrations exceeding solubility of substance in test medium: yes

Results with reference substance (positive control):

- Results with reference substance valid: yes
- nominal ErC50: 2.91 mg/L (95% confidence limits 2.35 - 3.63 mg/L)

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

For inhibition of growth of Pseudokirchneriella subcapitata after exposure to the test item (milled carbonised PAN based fibre) the NOEL values for both growth rate and yield are ≥ 100 mg/L and the EL50 is > 100 mg/L.

Executive summary:

A study was performed at the Fraunhofer Institute for Molecular Biology and Applied Ecology (IME) to determine the toxicity of the test item (milled carbonised PAN based fibre) on the growth of the unicellular fresh water green alga Pseudokirchneriella subcapitata. The algae were exposed under static conditions for a test period of 72 hours in accordance with the OECD guideline 201 and the EU method C.3. Eight replicates were used for both the control (test medium only) and test concentration.

The test item was prepared as a water accomodated fraction (WAF) in accordance with the OECD guidance document No. 23 on aquatic toxicity testing of difficult substances and mixtures in sterilised OECD growth medium without a solvent. A single limit loading of 100 mg/L was tested. No chemical analysis was performed. There was no concentration dependent effect on the growth (yield or growth rate) of Pseudokirchneriella subcapitata by the limit concentration of 100 mg/L. The yield (cell number) was inhibited by 10% and the growth rate by 2.4%.

For inhibition of growth of Pseudokirchneriella subcapitata after exposure to the test item (milled carbonised PAN based fibre) the NOEL values for both growth rate and yield are ≥ 100 mg/L and the EL50 is > 100 mg/L.