Registration Dossier

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:
read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Study period:
From April 24, 1990 to May 04, 1990
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Justification for type of information:
Refer to the Quaternary ammonium salts (QAS) category or section 13 for details on the category justification. The study with the read across substance is considered sufficient to fulfil the information requirements as further explained in the provided endpoint summary.
Reason / purpose:
read-across source
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
yes
Remarks:
KH2PO4 and NaHCO3 concentrations were 160 and 100 mg/L
GLP compliance:
yes
Specific details on test material used for the study:
- Lot/batch No.: G4 2892
- Physical state: Solid
- Analytical purity: >97%
Analytical monitoring:
no
Vehicle:
no
Details on test solutions:
A stock solution of 1 g/L was prepared in deionised water. Test solutions were prepared by dilution of the stock solution in OECD medium.
Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)
Details on test organisms:
Test organisms
- Common name: Selenastrum capricornutum ATCC 22662
- Source (laboratory, culture collection): ATCC
- Age of inoculum (at test initiation): exponentially growing
- Method of cultivation: identical as during the test
Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
72 h
Hardness:
Standard OECD medium
Test temperature:
22.5 - 23°C
pH:
6.8 - 7.6
Dissolved oxygen:
-
Salinity:
Standard OECD medium
Nominal and measured concentrations:
Nominal: 0, 0.01, 0.02, 0.04, 0.08 and 0.16 mg/L
Details on test conditions:
The culturing apparatus was a cabinet in which the temperature was maintained between 22 and 24°C, and continuous uniform illumination was provided in the spectral range of 400 to 700 m. The light intensity is in the range of 6000 to 10000 lux which is obtained by using seven 30 W fluorescenr lamps (colour temperature of approximately 4300 K), at a distance of 0.35 m from the algal culture. The culture flasks were rotated continuously at 100 rpm to prevent sedimentation of the algae.
Reference substance (positive control):
yes
Remarks:
Potassium dichromate 99.5% purity lot H0234 JT baker
Key result
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
0.08 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
growth rate
Remarks on result:
other: 0.07 - 0.08 mg/L 95% confidence limits
Key result
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
0.05 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
biomass
Remarks on result:
other: 0.04 - 0.05 mg/L 95% confidence limits
Key result
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
0.04 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
other: growth and growth rate
Key result
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
0.047 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
growth rate
Results with reference substance (positive control):
The absorbance measurement data of potassium dichromate included in the report. From results, an ErC50 and EbC50 (0-72 h) of potassium
dichromate of 0.57 and 0.23 mg/L, respectively, was calculated. These values of the reference compound were in accordance with data of an international interlaboratory test showing that the test organisms have not changed significantly and that the slight modification of the mineral salts medium do not influence the result.
Reported statistics and error estimates:
The EC50 values were computed from the best fitted line (least square method) through the points given by the probit of the percentage inhibition and the logarithm of the concentration of the test substance. The EC50 value calculated with the area under the growth curve is termed EbC50 (0-72h) whereas the EC value calculated with the specific growth rate is termed ErC50. Confidence limits were computed based on Fieller's theorem. All computations were performed with a programme (Akzo programme, Algal version 1.0) using the software package SAS.
Validity criteria fulfilled:
yes
Remarks:
but no chemical analysis was performed
Conclusions:
Under the study conditions, the 72h EbC50 and ErC50 of the test substance for Selenastrum capricornutum were 0.05 and 0.08 mg a.i./L, respectively. The NOEC for the effect on algal growth and growth rate was determined to be 0.04 mg/L.
Executive summary:

A study was conducted to determine the toxicity to green algae (Selenastrum capricornutum) of the read across substance, trimethyloctadecylammonium chloride (C18 TMAC), according to OECD Guideline 201, in compliance with GLP. In a range-finding test, algal growth was totally inhibited at nominal test concentrations of 1, 10 and 100 mg/L. Therefore, in the main test, algae were exposed for 72 h to nominal concentrations of 0.01, 0.02, 0.04, 0.08 and 0.16 mg a.i./L. Algal cell concentrations were determined spectrophotometrically. No analytical verification of dose concentrations was conducted. All the validity criteria of the study were fulfilled. Under the study conditions, the 72 h EbC50 and ErC50 were 0.05 and 0.08 mg a.i./L, respectively. The NOEC for the effects on both biomass and growth rate was determined to be 0.04 mg/L (van Ginkel, 1990).This ErC10 with a value of 0.047 mg/L is just a bit higher than the NOEC. The CV is much higher than the max of 35% indicating that this study is not valid based on the 2008 criteria. Also there is only one value which gives a partial response indicating that the test concentrations chosen were to widely distributed.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
KL2 due to RA
Justification for type of information:
Refer to the Quaternary ammonium salts (QAS) category or section 13 for details on the category justification. The study with the read across substance is considered sufficient to fulfil the information requirements as further explained in the provided endpoint summary.
Reason / purpose:
read-across source
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Qualifier:
according to
Guideline:
EU Method C.3 (Algal Inhibition test)
Qualifier:
according to
Guideline:
ISO 8692 (Water Quality - Fresh Water Algal Growth Inhibition Test with Scenedesmus subspicatus and Selenastrum capricornutum)
GLP compliance:
no
Specific details on test material used for the study:
- Analytical purity: 70.8%
Analytical monitoring:
yes
Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)
Test type:
static
Water media type:
saltwater
Limit test:
no
Total exposure duration:
96 h
Test temperature:
23.7 to 24.6°C
pH:
8.2 to 9.1
Nominal and measured concentrations:
Nominal concentrations: 0.035, 0.071, 0.142, 0.283 and 0.566 mg/L
Measured (concentrations were only measured for the low, middle and high concentrations):
0.03, 0.14 and 0.51 mg/L at 0 h, respectively and
0.01, 0.03 and 38 mg/L at 96 h, respectively.
Details on test conditions:
Based on the results of a range-finding test, Selenastrum capricornutum was exposed to the test substance at nominal concentrations of 0.035, 0.071, 0.142, 0.283 and 0.566 mg/L. The toxicity of the test substance to exponentially growing Selenastrum capricornutum was determined over an exposure period of 96 h. The test was conducted in a mineral salts medium at temperatures ranging from 23.7 to 24.6ºC in an illuminate orbital incubator. The pH in the test media varied from 8.2 to 9.1. The test was performed using six replicates for the control and three replicates for each concentration.
Reference substance (positive control):
yes
Remarks:
potassium dichromate
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
0.11 mg/L
Nominal / measured:
nominal
Basis for effect:
biomass
Key result
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
0.18 mg/L
Nominal / measured:
nominal
Basis for effect:
growth rate
Duration:
96 h
Dose descriptor:
EC10
Effect conc.:
0.104 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
growth rate
Details on results:
96-h EbC50 = 0.11 mg/L (0.11 - 0.12 mg/L)
96-h ErC50 = 0.18 mg/L (0.17 - 0.19 mg/L)
Results with reference substance (positive control):
EbC50 and ErC50 values of the reference compound, potassium dichromate were 0.8 and 1.5 mg/L, respectively

The test was valid as shown by the EbC50 and ErC50 values of the reference compound, potassium dichromate (0.8 and 1.5 mg/L, respectively), the increase of the extinction of the control over 72 h by a factor of 16 and by a maximum deviation of the pH of 0.9 units. Chemical analysis, using HPLC, of duplicate samples taken at the beginning of the test indicated that the exposure concentrations were substantially achieved (85 - 99% of the nominal values). The concentrations at the end of the test were strongly decreased (21 -67% of the nominal values), probably due to adsorption of the test substance to the test flask walls. Thus, EC values were calculated based on the nominal, rather than measured, concentrations.

Validity criteria fulfilled:
yes
Conclusions:
Under the test conditions, the EbC50 and ErC50 of the test substance to Selenastrum capricornutum at 96 h were found to be i.e., 0.08 and 0.13 mg a.i./L respectively. The ErC10 was determined to be 0.104 mg a.i./L
Executive summary:

A study was conducted to evaluate the toxicity of the read-across substance, tricetylmethyl ammonium chloride, toSelenastrum capricornutuma ccording to OECD Guideline 201, EU Method C.3 and ISO 8692, in compliance with GLP. Based on the results of a range-finding test,Selenastrum capricornutumwas exposed to the test substance at nominal concentrations of 0.035, 0.071, 0.142, 0.283 and 0.566 mg/L (i.e., 0.025, 0.05, 0.1, 0.2 and 0.4 mg a.i./L) under static conditions. Chemical analysis, using HPLC, of duplicate samples was taken at the beginning of the test indicated that the exposure concentrations were substantially achieved (85-99% of the nominal values). The concentrations at the end of the test were strongly decreased (21 -67% of the nominal values), probably due to adsorption of the test substance to the test flask walls. Thus, EC values were calculated based on the nominal, rather than measured, concentrations. The toxicity of the test substance to exponentially growingSelenastrum capricornutumwas determined over an exposure period of 96 h. The test was performed using six replicates for the control and three replicates for each concentration. All the validity criteria were fulfilled. Under the test conditions, the EbC50and ErC50of the test substance at 96 h were found to be 0.11 and 0.18 mg test substance/L (i.e., 0.08 and 0.13 mg a.i./L) respectively. The ErC10 was determined to be 0.104 mg a.i./L (Kroon AGM and Geurts MGJ, 1994).The mean CV is just >35% and also the increase factor over 72 h is 17.8 which is just larger than the criterium of 16. Therefore, the better reliable ErC10 value from this study is considered further in the risk assessment and C&L.

Description of key information

Based on the results of the read across studies, the 72 h ErC50 and ErC10 values of 0.08 and 0.104 mg a.i./L (nominal concentrations) (based on effects on alage) respectively are considered further for the hazard assessment of C16-18 and C18-unsatd. TMAC.

Key value for chemical safety assessment

EC50 for freshwater algae:
0.08 mg/L
EC10 or NOEC for freshwater algae:
0.104 mg/L

Additional information

Study 1: A study was conducted to determine the toxicity to green algae (Selenastrum capricornutum) of the read across substance, trimethyloctadecylammonium chloride (C18 TMAC), according to OECD Guideline 201, in compliance with GLP. In a range-finding test, algal growth was totally inhibited at nominal test concentrations of 1, 10 and 100 mg/L. Therefore, in the main test, algae were exposed for 72 h to nominal concentrations of 0.01, 0.02, 0.04, 0.08 and 0.16 mg a.i./L. Algal cell concentrations were determined spectrophotometrically. No analytical verification of dose concentrations was conducted. All the validity criteria of the study were fulfilled. Under the study conditions, the 72 h EbC50 and ErC50 were 0.05 and 0.08 mg a.i./L, respectively. The NOEC for the effects on both biomass and growth rate was determined to be 0.04 mg/L (van Ginkel, 1990). This ErC10 with a value of 0.047 mg/L is just a bit higher than the NOEC. The CV is much higher than the max of 35% indicating that this study is not valid based on the 2008 criteria. Also there is only one value which gives a partial response indicating that the test concentrations chosen were to widely distributed.

Study 2:A study was conducted to evaluate the toxicity of the read-across substance, tricetylmethyl ammonium chloride, toSelenastrum capricornutuma ccording to OECD Guideline 201, EU Method C.3 and ISO 8692, in compliance with GLP. Based on the results of a range-finding test,Selenastrum capricornutum was exposed to the test substance at nominal concentrations of 0.035, 0.071, 0.142, 0.283 and 0.566 mg/L (i.e., 0.025, 0.05, 0.1, 0.2 and 0.4 mg a.i./L) under static conditions. Chemical analysis, using HPLC, of duplicate samples was taken at the beginning of the test indicated that the exposure concentrations were substantially achieved (85-99% of the nominal values). The concentrations at the end of the test were strongly decreased (21 -67% of the nominal values), probably due to adsorption of the test substance to the test flask walls. Thus, EC values were calculated based on the nominal, rather than measured, concentrations. The toxicity of the test substance to exponentially growingSelenastrum capricornutumwas determined over an exposure period of 96 h. The test was performed using six replicates for the control and three replicates for each concentration. All the validity criteria were fulfilled. Under the test conditions, the EbC50and ErC50of the test substance at 96 h were found to be 0.11 and 0.18 mg test substance/L (i.e., 0.08 and 0.13 mg a.i./L) respectively. The ErC10 was determined to be 0.104 mg a.i./L (Kroon AGM and Geurts MGJ, 1994).The mean CV is just >35% and also the increase factor over 72 h is 17.8 which is just larger than the criterium of 16. Therefore, the better reliable ErC10 value from this study is considered further in the risk assessment and C&L.