4,4'-dioxo-4,4'-dioxydibutyric acid

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2018

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

Justification for type of information:

Please refer to attached QMRF and QPRF documents.

Qualifier:

according to guideline

Guideline:

other: REACH Guidance on QSAR R.6

Principles of method if other than guideline:

Calculation of toxicity in algae. Software used: ECOSAR 1.11 (EPISUITE) for chemical class "Peroxyester" and "Neutral Organic SAR (Baseline Toxicity)"

GLP compliance:

no

Specific details on test material used for the study:

SMILES: C(CC(=O)O)CC(=O)OOC(=O)CCCC(=O)O

Analytical monitoring:

not required

Test organisms (species):

other: Desmodesmus subspicatus and Pseudokirchneriella subcapitata

Water media type:

freshwater

Total exposure duration:

96 h

Key result

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

90.822 mg/L

Remarks on result:

other: QSAR estimated values. The substance is within the applicability domain of the model.

--------------------------------------

ECOSAR v1.11 Class-specific Estimations

--------------------------------------

Peroxy Esters -acid

Predicted

 

ECOSAR Class	Organism	Duration	End Pt	mg/L (ppm)
Peroxy Esters -acid:	Green Algae	96-hr	EC50	90.822

 

--> Acid moeity found: Predicted values multiplied by 10

Validity criteria fulfilled:

yes

Conclusions:

Using ECOSAR v1.11 the toxicity value for algae (EC50, 96h) was calculated to be 90.82 mg/L. The substance is within the applicability domain of the model.

Executive summary:

The toxicity in algae was calculated using ECOSARv 1.11 as part of EPISuite v4.11 from US Environmental Protection Agency.

Using ECOSAR v1.11 the toxicity value for algae (EC50, 96h) was calculated to be 90.82 mg/L.

The adequacy of a prediction depends on the following conditions:

a) the (Q)SAR model is scientifically valid: the scientific validity is established according to the OECD principles for (Q)SAR validation;

b) the (Q)SAR model is applicable to the query chemical: a (Q)SAR is applicable if the query chemical falls within the defined applicability domain of the model;

c) the (Q)SAR result is reliable: a valid (Q)SAR that is applied to a chemical falling within its applicability domain provides a reliable result;

d) the (Q)SAR model is relevant for the regulatory purpose.

 

For assessment and justification of these 4 requirements the QMRF and QPRF files were developed and attached to this study record.

 

Description of the prediction Model

The prediction model was descriped using the harmonised template for summarising and reporting key information on (Q)SAR models. For more details please refer to the attached QSAR Model Reporting Format (QMRF) file. 

 

Assessment of estimation domain

The assessment of the estimation domain was documented in the QSAR Prediction Reporting Format file (QPRF). Please refer to the attached document for the details of the prediction and the assessment of the estimation domain.

Description of key information

Using ECOSAR v1.11 the toxicity value for algae (EC50, 96h) was calculated to be 90.82 mg/L. The substance is within the applicability domain of the model.

Key value for chemical safety assessment

EC50 for freshwater algae:

90.82 mg/L

Additional information

The toxicity in algae was calculated using ECOSAR v 1.11 as part of EPISuite v4.11 from US Environmental Protection Agency.

Using ECOSAR v1.11 the toxicity value for algae (EC50, 96h) was calculated to be 90.82 mg/L.

The adequacy of a prediction depends on the following conditions:

a) the (Q)SAR model is scientifically valid: the scientific validity is established according to the OECD principles for (Q)SAR validation;

b) the (Q)SAR model is applicable to the query chemical: a (Q)SAR is applicable if the query chemical falls within the defined applicability domain of the model;

c) the (Q)SAR result is reliable: a valid (Q)SAR that is applied to a chemical falling within its applicability domain provides a reliable result;

d) the (Q)SAR model is relevant for the regulatory purpose.

 For assessment and justification of these 4 requirements the QMRF and QPRF files were developed and attached to this study record.

 Description of the prediction Model

The prediction model was descriped using the harmonised template for summarising and reporting key information on (Q)SAR models. For more details please refer to the attached QSAR Model Reporting Format (QMRF) file. 

 Assessment of estimation domain

The assessment of the estimation domain was documented in the QSAR Prediction Reporting Format file (QPRF). Please refer to the attached document for the details of the prediction and the assessment of the estimation domain.

Additional information is available on the hydrolysis product succinic acid (CAS 110-15-6, EC 203-740-4) from the ECHA Dissemination Webpage. In the registration dossier data on all endpoints concerning ecotoxicity are available: According to an OECD 201 study the acute toxicity to aquatic algae was determined to be: ErC50 > 100 mg/L, NOEC = 100 mg/L after pH adjustment.

Scientific tests with information about the toxicity of the test item are available for two other trophic levels: The values for fish (LC50 > 73 mg/L) and daphnia (EC50 = 13 mg/L) are lower than the calculated EC50 of algae. Based on the combination of the available information on the toxicity of the test item towards fish and daphnia and the hydrolysis product, the toxicity of algae is not the determining factor for aquatic toxicity. Thus, a new test for toxicity to aquatic algae is not required.