Registration Dossier

Diss Factsheets

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Currently viewing:

Administrative data

Link to relevant study record(s)

Referenceopen allclose all

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
not specified
Remarks:
SDS
Adequacy of study:
weight of evidence
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
documentation insufficient for assessment
Principles of method if other than guideline:
no data
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
> 10 mg/L
Remarks on result:
other: MSDS
Validity criteria fulfilled:
not applicable
Conclusions:
The EC50 (96h) is > 10 mg/L.
Executive summary:

The EC50 (96h) is > 10 mg/L.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
calculation (if not (Q)SAR)
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification
Principles of method if other than guideline:
calculation
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
325.707 mg/L
Remarks on result:
other: ECOSAR v1.11 calculation, Neutral Organics SAR class
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
59.842 mg/L
Remarks on result:
other: ECOSAR v1.11 calculation, Neutral Organics SAR class
Validity criteria fulfilled:
not applicable
Conclusions:
The calculated (ECOSAR v1.11, Neutral Organics SAR class) EC50 (96h) is 325.707 mg/L, ChV is 59.842 mg/L.
Executive summary:

The calculated (ECOSAR v1.11, Neutral Organics SAR class) EC50 (96h) is 325.707 mg/L, ChV is 59.842 mg/L.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
calculation (if not (Q)SAR)
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification
Principles of method if other than guideline:
calculation
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
183.651 mg/L
Remarks on result:
other: ECOSAR v1.11 calculation, Neutral Organics SAR class
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
37.328 mg/L
Remarks on result:
other: ECOSAR v1.11 calculation, Neutral Organics SAR class
Validity criteria fulfilled:
not applicable
Conclusions:
The calculated (ECOSAR v1.11, Neutral Organics SAR class) EC50 (96h) is 183.651 mg/L, ChV is 37.328 mg/L.
Executive summary:

The calculated (ECOSAR v1.11, Neutral Organics SAR class) EC50 (96h) is 183.651 mg/L, ChV is 37.328 mg/L.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Remarks:
Screening study on the multiconstituent product
Type of information:
experimental study
Remarks:
Screening studies non GLP
Adequacy of study:
weight of evidence
Study period:
9-10-2017- 12-10-2017
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Justification for type of information:
OECD 201 guideline was followed and a certificate of analysis was included. Study repeated with 2 x Stock preparation methods. No chemical analysis was conducted. Test material is a multi constituent substance in stabilizer and toxicity endpoint is therfore an indication of Nominal toxicity of the product.
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
yes
Remarks:
Guideline followed in an adapted form for toxicity screening purposes
Principles of method if other than guideline:
Guideline was followed without chemical analysis and with 2 different stock preparation techniques.
GLP compliance:
no
Specific details on test material used for the study:
Trade name: Trigonox. ®. ADC-NS30
Chemical name : Peroxydicarbonate mixture
CAS : 78350-78-4 19910-65-7;10-564-6.
Batch/lot 0359 (Reach) 16041B0206 (certificate provided)
Appearance/Colour Clear liquid
Solubility Not provided
Stability SADT = 0 ºC rapid self decomposition at room temperature
Purity percentage 30%
Analytical monitoring:
no
Details on sampling:
N/A
Vehicle:
no
Details on test solutions:
Preparation of the stock solutions
The test material was accurately weighed using an analytical balance and added to 100 ml of test medium to make a known (128 mg/L) stock solution. This was then stirred thoroughly until a homogeneous stock was achieved. The test material appeared to disperse easily. Sufficient volumes of stock were then added to the test vessels (whilst stirring the stock) in order to reach the desired test concentrations in a total test volume of 40 ml per replicate. The stock was used directly for the highest test concentration without dilution. The pH of the stocks were all measured and were all found to be close to the pH of the test medium. pH was therefore not adjusted further.

Test concentrations

0.01, 0.1, 1.0, 10.0 and 100 mg/L including a control were prepared for testing from a stock solution and tested directly. (Preparation method stock)

1.0 10.0 and 100.0 mg/L were weighed separately into Duran bottles containing 1L of test medium and equipped with a Teflon tap (WAF Flasks). After 48-72 hours slow stir the water accommodated fraction was removed and tested directly. A control without test substance was prepared in an identical manner using test medium only. (Preparation method WAF)

Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)
Details on test organisms:
The test was carried out with the freshwater unicellular algae Pseudokirchneriella subcapitata (CCAP 278/4) obtained from the Culture Collection of Algae and Protozoa SAMS Research Services Ltd. Dunstaffnage Marine Laboratory, Dunbeg, Argyll, Scotland. After purchasing this strain was cultured and maintained. Cultures on sloped agar tubes were stored at 4°C in the dark until required. Exponentially growing cultures are maintained at 23 ± 2°C in a temperature-controlled illuminated orbital incubator and are re-cultured under sterile conditions weekly to keep the algae in this phase. The sensitivity of the algae was checked by performing a growth inhibition test with a reference compound (potassium dichromate) twice a year , and is not used unless found to be between the set EC50 values of 0.25 to 2.0 mg/L as indicated in the study guideline.
Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
72 h
Hardness:
Standard OECD medium used with additional NaHCO3 for better pH stability
Test temperature:
23 ± 2°C
pH:
7.8
Dissolved oxygen:
N/A
Salinity:
N/A
Conductivity:
Not measured
Nominal and measured concentrations:
0.01, 0.1, 1.0, 10.0 and 100 mg/L made from stock solution

1.0 10.0 and 100.0 mg/L made form WAF slow stir
Details on test conditions:
TEST SYSTEM
- Test vessel: 100 mg erlenmeyer
- Type (delete if not applicable): closed with non air tight paper stop
- Material, size, headspace, fill volume: 40ml
- Aeration: no
- Initial cells density: 10000 cells /ml
- Control end cells density: control passed the 16 X cell density increase required by guideline
-
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 4

GROWTH MEDIUM
- Standard medium used: yes
- Detailed composition if non-standard medium was used: elevated NaHCO3


OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: Was not required
- Photoperiod: 24 hours per day
- Light intensity and quality: 80-120 µmol m-2s-1
- Salinity (for marine algae): N/A

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: [ spectrophotometer for which absorbance is checked yearly in a calibration curve using a counting chamber]
- Chlorophyll measurement: indirectly at 436 nM
- Other:

TEST CONCENTRATIONS
- Spacing factor for test concentrations: Factor 10 (Screening)
- Justification for using less concentrations than requested by guideline: Screening test
- Range finding study No


















- Test concentrations:
- Results used to determine the conditions for the definitive study:
Reference substance (positive control):
yes
Remarks:
Conducted twice yearly as part of lab maintenance
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
8.8 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Remarks on result:
other: Without pre degradation
Remarks:
Normal Stock Prep
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
8.2 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Remarks on result:
other: With degradation
Remarks:
WAF prep
Details on results:
Nominal toxicity range determined
Results with reference substance (positive control):
Positive reference was reported as guideline complant as part of laboratory maintenance
Reported statistics and error estimates:
Area under the curve and the specific growth rate were calculated according to OECD 201 guideline
using the absorbance values to calculate the growth inhibition in comparison to the control. See tables 1&2. This data to generate a dose response curves using a statistical software package (Toxcalc 5.0) was used.
Validity criteria fulfilled:
yes
Remarks:
Valid as supporting evidence with limitations
Conclusions:
The study can be considered reliable as supporting evidence with the restrictions mentioned.
Executive summary:

The study was conducted according to the basis of the OECD 201 guideline with acceptable test material identification information. Study lacked GLP and chemical analysis. Experiments were repeated and showed good concordance with each other. It is likely that rapid degradation has taken place and that toxicity was caused by the stabilizing agent and/or degradation products. Data can be used to indicate the nominal toxicity of the product as a whole and is considered valid as supporting evidence when accompanyied by an additional endpoint for algae toxicity form a relevant or related substance. Due to the stable component of the material likely being the cause of the toxicity the lack of chemical analysis is not considered a critical restriction.

Description of key information

The endpoint is fulfilled using Weight of Evidence. An OECD 201 study with the Reaction mass of bisisopropyl peroxydicarbonate and bis-sec-butyl peroxydicarbonate and isopropylsecbutylperoxydicarbonate

gave a 72h-EC50 of 8.2 mg/L loading rate.

It was demonstrated that the organic peroxides present in the Reaction mass rapidly hydrolyze (see 5.1.2) to Isopropanol (CAS 67 -63 -0) and Sec-butanol (CAS 78 -92 -2). The ECOSAR acute endpoints for the hydrolysis byproducts are all > 100 mg/L.

The stabilizing agent (CAS 142 -22 -3) present in the test material does not show rapid hydrolysis. The EC50 for algae for this substance is greater than 10 mg/L.

It is assumed that effects seen in the test with the Reaction mass are caused by the stabilizing agent.

The test result obtained with the Reaction mass is somewhat more conservative than that of the stabilizer.

Key value for chemical safety assessment

EC50 for freshwater algae:
8.2 mg/L

Additional information