2-phenyl-1H-benzimidazole-5-sulphonic acid

Long-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

fish early-life stage toxicity

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2021

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:

For detailed description of the model and its applicability domain, see attached QMRF and QPRF document

Qualifier:

according to guideline

Guideline:

other: REACH guidance on QSAR R.6

Principles of method if other than guideline:

Calculation of Long-Term toxicity in fish. Software used: ECOSAR 2.0 for chemical class "Pyrroles/Diazoles"

GLP compliance:

no

Specific details on test material used for the study:

SMILES: OS(=O)(=O)c1ccc2[nH]c(nc2c1)c3ccccc3

Analytical monitoring:

not required

Test organisms (species):

other: fish

Water media type:

freshwater

Total exposure duration:

30 d

Remarks on exposure duration:

chronic exposure

Key result

Duration:

30 d

Effect conc.:

65.22 mg/L

Remarks on result:

ChV (chronic value, QSAR)

Remarks:

The substance is within the applicability domain of the model. ECOSAR class "Pyrroles/Diazoles".

Organism	Duration	Endpoint	Concentration (mg/L)	Max Log Kow	Flags
Fish	96h	LC50	353153.06	5	Chemical may not be soluble enough to measure this predicted effect. If the effect level exceeds the water solubility by 10X, typically no effects at saturation (NES) are reported.
Daphnid	48h	LC50	20542.78	5	Chemical may not be soluble enough to measure this predicted effect. If the effect level exceeds the water solubility by 10X, typically no effects at saturation (NES) are reported.
Green Algae	96h	EC50	496.72	6.4	Chemical may not be soluble enough to measure this predicted effect. If the effect level exceeds the water solubility by 10X, typically no effects at saturation (NES) are reported.
Fish		ChV	65.22	8
Daphnid		ChV	350.83	8	Chemical may not be soluble enough to measure this predicted effect. If the effect level exceeds the water solubility by 10X, typically no effects at saturation (NES) are reported.
Green Algae		ChV	170.19	8	Chemical may not be soluble enough to measure this predicted effect. If the effect level exceeds the water solubility by 10X, typically no effects at saturation (NES) are reported.
Mysid (SW)	96h	LC50	1768.02	5	Chemical may not be soluble enough to measure this predicted effect. If the effect level exceeds the water solubility by 10X, typically no effects at saturation (NES) are reported.

Validity criteria fulfilled:

yes

Conclusions:

Using ECOSAR v2.0 the long-term toxicity ChV value for fish was calculated to be 65.22 mg/L. The substance is within the applicability domain of the model.

Executive summary:

The long-term toxicity in fish was calculated using ECOSAR v2.0 from US Environmental Protection Agency.

 

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

According to Annex XI, paragraph 1.3 results obtained from valid QSAR models may be used instead of testing. A valid QSAR calculation is available for this endpoint showing that the substance is not chronic toxic to fish (ChV = 65.22 mg/L).

Based on the results of the QSAR calculation for the long-term toxicity to fish,  the information from the short-term aquatic toxicity tests with fish, daphnia and algae and the information from the chronic algae and daphnia tests - it can be shown that the substance is not aquatic toxic. Thus, to avoid unnecessary testing on vertebrate animals no additional test on long-term toxicity to fish is needed to be able to conclude on the non-toxicity of the substance for aquatic organisms.

Furthermore, this is supported by the good solubility in water (109 mg/L) and the low bioaccumulation potential (log Kow = -1.42).