Recyclamine R 501

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Justification for type of information:

Data is from computational model developed by USEPA

Qualifier:

according to guideline

Guideline:

other: Modelling database

Principles of method if other than guideline:

Estimation 96 hrs EC50 value of test chemical on aquatic algae by EPI Suite ECOSAR version 1.11.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

other: green algae

Test type:

static

Water media type:

freshwater

Total exposure duration:

96 h

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

287.873 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: Neutral Organic SAR (Baseline Toxicity)

Validity criteria fulfilled:

not specified

Conclusions:

Based on effect of test chemical on the growth rate of the test organism green algae, the 96 hrs EC50 value was estimated to be 287.873 mg/l.

Executive summary:

The toxicity of the test chemical to green algae was predicted using EPI Suite ECOSAR version 1.11. On the basis of effect of test chemical observed in a static system on the growth rate of the test organism during the 96 hr exposure duration, the median effect concentration (EC50) for the test chemical was estimated to be 287.873 mg/l. Thus, based on the EC50 value, test chemical was considered as non-toxic and hence, considered to be 'not classified' as per the CLP classification criteria.

Description of key information

A freshwater algal growth inhibition test was conducted for 72 hrs for assessing the effect of test chemical on green algae Pseudokirchneriella subcapitata. The test was performed in accordance to OECD guideline No. 201 – Alga growth inhibition test under static condition. Initial cell density of the culture was kept at 10000 cells/ml. OECD medium composed of macronutrients, micronutrients, alkaline EDTA solution and iron solution was used as a growth medium. The saturated test solution was prepared by dissolving 250mg of test chemical in 250ml of OECD media, and allowed for stirring for 96 hours, which was then filtered and the final saturated stock solution obtained was 1000 mg/L, verified analytically by UV-Vis Spectrophotometer. To have a better growth and visibility of cells, the initial cell count of the culture was kept 10,000 cells/mL. Further, exposure concentrations of 0, 7, 14, 28, 56 and 112 mg/l, respectively was from the saturated test concentrations. Test vessel were placed in orbital shaking incubator for 72 hrs at a temperature of 23 °C and with a continuous uniform illumination of 6000 -10000 lux light intensity, respectively. The speed of the orbital shaking incubator was set at a 120 revolutions per minute throughout the study period. The cultures were counted and observed daily with the help of a microscope. Potassium dichromate (K2Cr2O7) was used as a reference substance. The 72 hr EC50 value of the reference substance was determined to be 0.868 mg/l. The biomass in the control vessel have increased exponentially by a factor of 16 and the mean coefficient of variation of specific growth rate was not exceeded 35%, thus fulfilling the validity criterion. As the concentration of the test chemical being tested has not been satisfactorily maintained within ± 20 % of the nominal concentration throughout the test. Therefore, the analysis of the results was based on measured concentration. On the basis of growth rate of the test organism, the 72 hr median effect concentration (EC50) was determined to be >112 mg/l (nominal conc.). Thus, test chemical was considered as non-toxic to aquatic algae and hence, considered to be 'not classified' as per the CLP classification criteria.

Key value for chemical safety assessment

EC50 for freshwater algae:

112 mg/L

Additional information

Experimental and predicted data of the target chemical were reviewed for toxicity to aquatic algae and cyanobacteria endpoint which are summarized as below:

In an experimental study from study report, a freshwater algal growth inhibition test was conducted for 72 hrs for assessing the effect of test chemical on green algae Pseudokirchneriella subcapitata. The test was performed in accordance to OECD guideline No. 201 – Alga growth inhibition test under static condition. Initial cell density of the culture was kept at 10000 cells/ml. OECD medium composed of macronutrients, micronutrients, alkaline EDTA solution and iron solution was used as a growth medium. The saturated test solution was prepared by dissolving 250mg of test chemical in 250ml of OECD media, and allowed for stirring for 96 hours, which was then filtered and the final saturated stock solution obtained was 1000 mg/L, verified analytically by UV-Vis Spectrophotometer. To have a better growth and visibility of cells, the initial cell count of the culture was kept 10,000 cells/mL. Further, exposure concentrations of 0, 7, 14, 28, 56 and 112 mg/l, respectively was from the saturated test concentrations. Test vessel were placed in orbital shaking incubator for 72 hrs at a temperature of 23 °C and with a continuous uniform illumination of 6000 -10000 lux light intensity, respectively. The speed of the orbital shaking incubator was set at a 120 revolutions per minute throughout the study period. The cultures were counted and observed daily with the help of a microscope. Potassium dichromate (K2Cr2O7) was used as a reference substance. The 72 hr EC50 value of the reference substance was determined to be 0.868 mg/l. The biomass in the control vessel have increased exponentially by a factor of 16 and the mean coefficient of variation of specific growth rate was not exceeded 35%, thus fulfilling the validity criterion. As the concentration of the test chemical being tested has not been satisfactorily maintained within ± 20 % of the nominal concentration throughout the test. Therefore, the analysis of the results was based on measured concentration. On the basis of growth rate of the test organism, the 72 hr median effect concentration (EC50) was determined to be >112 mg/l (nominal conc.). Thus, test chemical was considered as non-toxic to aquatic algae and hence, considered to be 'not classified' as per the CLP classification criteria.

 

Toxicity of the test chemical to green algae was predicted using EPI Suite ECOSAR version 1.11 (2019). On the basis of effect of test chemical observed in a static system on the growth rate of the test organism during the 96 hr exposure duration, the median effect concentration (EC50) for the test chemical was estimated to be 287.873 mg/l.

On the basis of the above results, test chemical was considered as non-toxic to aquatic algae at environmental relevant concentrations and hence, considered to be 'not classified' as per the CLP classification criteria.