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Toxicity to aquatic algae and cyanobacteria

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Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: But-1-ene CAS number: 106-98-9 SMILES structure:C(=C)CC
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
14.882 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
4.035 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 14.882 and 4.035 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance But-1-ene towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 14.882 mg/L and 4.035 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: But-2-ene, trans- CAS number: 624-64-6 SMILES structure: C(=CC)C
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
16.868 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
4.501 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 16.868 and 4.501 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance But-2-ene, trans- towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 16.868 mg/L and 4.501 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: Buta-1,3-diene CAS number:106-99-0 SMILES structure:C(C=C)=C
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
17.832 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
4.702 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 17.832 and 4.702 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance Buta-1,3-diene towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 17.832 mg/L and 4.702 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: Butane CAS number: 106-97-8 SMILES structure: C(CC)C
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
12.405 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
3.459 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 12.405 and 3.459 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance Butane towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 12.405 mg/L and 3.459 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: Carbon Monoxide CAS number: 630-08-0 SMILES structure: O1=C=1
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
124.406 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
23.452 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 124.406 and 23.452 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance Carbon Monoxide towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 124.406 mg/L and 23.452 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: Ethane CAS number: 74-84-0 SMILES structure: CC
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
30.707 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
6.997 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 30.707 and 6.997 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance Ethane towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 30.707 mg/L and 6.997 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: Ethene [aka Ethylene] CAS number: 74-85-1 SMILES structure: C=C
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
31.413 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
7.074 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 31.413 and 7.074 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance Ethene [aka Ethylene] towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 31.413 mg/L and 7.074 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: Pentane CAS number: 109-66-0 SMILES structure: C(CCC)C
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
7.039 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
2.172 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 7.039 and 2.172 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance Pentane towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 7.039 mg/L and 2.172 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: Prop-1-ene CAS number: 115-07-1 SMILES structure: C(=C)C
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
24.416 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
5.985 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 24.416 and 5.985 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance Prop-1-ene towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 24.416 mg/L and 5.985 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: Prop-1-ene, 2-methyl- CAS number: 115-11-7 SMILES structure: C(=C)(C)C
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
13.607 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
3.733 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 13.607 and 3.733 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance Prop-1-ene, 2-methyl- towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 13.607 mg/L and 3.733 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: Propane CAS number: 74-98-6 SMILES structure: C(C)C
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
20.586 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
5.19 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 20.586 and 5.190 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance Propane towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 20.586 mg/L and 5.190 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: Propane, 2-methyl- CAS number: 75-28-5 SMILES structure: C(C)(C)C
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
13.946 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
3.831 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 13.946 and 3.831 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance Propane, 2-methyl- towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 13.946 mg/L and 3.831 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance:But-2-ene, cis- CAS number:590-18-1 SMILES structure:C(=CC)C
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
16.868 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
4.501 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 16.868 and 4.501 mg/L, respectively.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of substance But-2-ene, cis- towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 16.868 mg/L and 4.501 mg/L, respectively.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR calculation, reliable with restrictions
Justification for type of information:
Measured data are not available for this substance and endpoint. Due to the practical difficulties associated with the ecotoxicity testing of this substance, the use of QSAR toxicity estimates is an appropriate alternative. The ECOSAR model is a reliable and appropriate QSAR model to apply to this substance as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity.
Principles of method if other than guideline:
The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols. Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.
GLP compliance:
no
Specific details on test material used for the study:
Program: ECOSAR v.1.11 (Epi Suite 4.1)

Substance: Methane CAS number: 74-82-8 SMILES structure: C
Analytical monitoring:
no
Details on sampling:
not applicable
Vehicle:
no
Details on test solutions:
not applicable
Test organisms (species):
other: green algae
Details on test organisms:
not applicable
Test type:
not specified
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
not applicable
Hardness:
not applicable
Test temperature:
not applicable
pH:
not applicable
Dissolved oxygen:
not applicable
Salinity:
not applicable
Nominal and measured concentrations:
not applicable
Details on test conditions:
not applicable
Reference substance (positive control):
no
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
39.195 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
growth rate
Remarks on result:
other: QSAR prediction value
Duration:
96 h
Dose descriptor:
other: ChV
Effect conc.:
7.981 mg/L
Nominal / measured:
estimated
Conc. based on:
other: QSAR prediction
Basis for effect:
not specified
Remarks on result:
other: QSAR prediction value
Details on results:
Methane is not soluble enough to measure the predicted short-term effect.

The ChV, or Chronic Value, is defined as the geometric mean of the no observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC). This can be mathematically represented as: ChV = 10^([log (LOEC x NOEC)]/2).
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable
Validity criteria fulfilled:
not applicable
Remarks:
Calculated value
Conclusions:
The estimated 96-hour EC50 and ChV for green algae were 39.195 and 7.981 mg/L, respectively. However, methane is not soluble enough to measure the predicted short-term effect.
Executive summary:

The ECOSAR model was used as a reliable and appropriate QSAR model to estimate the baseline toxicity of the substance Methane towards green algae. The 96 -hour EC50 and ChV for green algae were estimated to be 39.195 mg/L and 7.981 mg/L, respectively. However, methane is not soluble enough to measure the predicted short-term effect.

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP compliant, guideline study, available as unpublished reported, no restrictions fully adequate for assessment
Qualifier:
according to guideline
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
GLP compliance:
yes
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material :
not applicable
Analytical monitoring:
yes
Details on sampling:
Samples were taken daily through a septum in the test vessel. Samples from each test concentration were pooled.
Vehicle:
no
Details on test solutions:
Benzene was added directly to algal medium to form a stock solution. This was then diluted serially to produce the desired test concentrations.
Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)
Details on test organisms:
ATCC 22662. Algae were taken from a preculture in log phase growth.
Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
72 h
Post exposure observation period:
none
Hardness:
24.2mg/L equivalent to CaCO3
Test temperature:
23±2°C
pH:
7 at start of test, 7-8.8 at end of test
Dissolved oxygen:
not measured
Salinity:
not applicable
Nominal and measured concentrations:
1.3, 4.3, 13, 43 and 134mg/L nominal. Measured concentrations remained between 83-100% of initial measurements throughout test. Results are reported as initial measured concentrations: 0.7, 2.6, 8.0, 27 and 98mg/L.
Details on test conditions:
Standard growth medium used, but 300mg/L NaHCO3 not 50mg/L as specified in OECD 201. Test vessels were 40ml cylindrical glass vials. An initial cell density of 1.40E+03 cells/ml and a control end cells density of 5.50E+05 cells/ml. Cell concentrations determined with an Electronic particle counter (Coulter Multisizer Iie). Five replicates per test concentration and sampling point (after sampling vessels were discarded) kept under continuous illumination at a light intensity of 60-120µmol/m2/sec.


Reference substance (positive control):
no
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
32 mg/L
Nominal / measured:
meas. (not specified)
Conc. based on:
test mat.
Basis for effect:
biomass
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
100 mg/L
Nominal / measured:
meas. (not specified)
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
10 mg/L
Nominal / measured:
meas. (not specified)
Conc. based on:
test mat.
Basis for effect:
biomass
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
34 mg/L
Nominal / measured:
meas. (not specified)
Conc. based on:
test mat.
Basis for effect:
growth rate
Details on results:
Effect values based on measured concentrations.
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
data not reported
Validity criteria fulfilled:
not specified
Conclusions:
The 72 hour EC50 is 100mg/L and the 72 hour EC10 is 34mg/L
Executive summary:

This study followed a standard guideline and was conducted to GLP. A closed system was used due to the volatility of the test substance, so reduced starting cell numbers were used and pH adjusted. This is therefore suitable for use as the key study and was used as the key study for this endpoint in the EU RAR for benzene (2002).

Description of key information

The members of this category are gases at standard temperature and pressure and will predominantly partition to the atmosphere, what will limit their aquatic toxicity. Consequently, conducting aquatic ecotoxicity tests is technically difficult and based on exposure estimates the test may not be relevant. In addition, it is difficult to assess the toxicity of UVCB streams using standard test methods. Instead, it is more appropriate to consider the toxicity of representative components of these streams.

Due to the difficulty associated with conducting aquatic toxicity tests, experimental data is available only for a members of this category: Benzene (CAS 71-43-2). The 72-hour EC50 and EC10 for benzene for Pseudokirchneriella subcapitata were 100 mg/L and 34 mg/L, respectively.

 

For the other members of this category, the use of QSAR to predict the ecotoxicity of representative components of these streams is an appropriate technique for aquatic toxicity. ECOSAR v.1.11 (Epi Suite 4.1) has been used as key QSAR. The representative substances of the category studied and used as supporting read-across are But-1-ene (CAS 106-98-9),  But-2-ene, cis- (CAS 590-18-1), But-2-ene, trans- (CAS 624-64-6), Buta-1,3-diene (CAS 106-99-0), Butane (CAS 106-97-8), Carbon Monoxide (CAS 630-08-0), Ethane (CAS 74-84-0), Ethene [aka Ethylene] (CAS 74-85-1), Methane (CAS 74-82-8), Pentane (CAS 109-66-0), Prop-1-ene (CAS 115-07-1), Prop-1-ene, 2-methyl- (CAS 115-11-7), Propane (CAS 74-98-6), Propane, 2-methyl- (CAS 75-28-5). The model estimated EC50 for short-term toxicity to aquatic algae and cyanobacteria to range from 7.04 mg/L to 124 mg/L, whereas the chronic value for long-term toxicity to aquatic algae and cyanobacteria was estimated to range from 2.17 mg/L to 23.5 mg/L.

Key value for chemical safety assessment

Additional information

Experimental data

An algal study is available which report results after 72 hours exposure. The study  used Pseudokirchneriella subcapitata in standard OECD 201 studies using closed systems and the effect values are based on measured concentrations. Following the same approach as set out in the EU RAR (2008), as Galassi et al., (1988) only derive an EC50 value with no information available on the no effect level, the results found by TNO (2001) will be used for the further effects assessment.

 

QSAR data

The ECOSAR class program has been developed primarily for the evaluation of neutral organic compounds and organic classes with excess toxicity. The QSARs in the ECOSAR program are developed for chemical classes based on measured test data that have been submitted by industry or they are developed by other sources for chemicals with similar structures, e.g., phenols.  Using the measured aquatic toxicity values and estimated Kow values, regression equations can be developed for a class of chemicals. Toxicity values for new chemicals may then be calculated by inserting the Kow value into the regression equation and correcting the resultant value for the molecular weight of the compound.

 

The calculated values were:

 

Constituent Name CAS number EC50 Algae (mg/L) ChV Algae (mg/L)
But-1-ene 106-98-9 14.88 4.04
But-2-ene, cis- 590-18-1 16.87 4.50
But-2-ene, trans- 624-64-6 16.87 4.50
Buta-1,3-diene 106-99-0 17.83 4.70
Butane 106-97-8 12.41 3.46
Carbon Monoxide 630-08-0 124.41 23.45
Ethane 74-84-0 30.71 7.00
Ethene   [aka Ethylene] 74-85-1 31.41 7.07
Methane 74-82-8 39.20* 7.98
Pentane 109-66-0 7.04 2.17
Prop-1-ene 115-07-1 24.42 5.99
Prop-1-ene, 2-methyl- 115-11-7 13.61 3.73
Propane 74-98-6 20.59 5.19
Propane, 2-methyl- 75-28-5 13.95 3.83

*Methane is not soluble enough to measure this predicted short-term effect.