Pyrazine-2-carboxylic acid

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

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 limited documentation / justification

Justification for type of information:

The supporting QMRF report has been attached

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Principles of method if other than guideline:

The data is predicted using the OECD QSAR toolbox version 3.4 with logKow as the primary descriptor.

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material: Pyrazine-2-carboxylic acid
- Molecular formula: C5H4N2O2
- Molecular weight: 124.099 g/mol
- Substance type: organic
- Physical state: solid
- Smiles: c1ncc(C(=O)O)nc1
- InChI: 1S/C5H4N2O2/c8-5(9)4-3-6-1-2-7-4/h1-3H,(H,8,9)

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Test type:

semi-static

Water media type:

freshwater

Total exposure duration:

96 h

Test temperature:

20 deg.C

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

116.63 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Sublethal observations / clinical signs:

The prediction was based on dataset comprised from the following descriptors: LC50
Estimation method: Takes average value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

(((((((("a" or "b" or "c" or "d" )  and ("e" and ( not "f") )  )  and ("g" and ( not "h") )  )  and ("i" and ( not "j") )  )  and "k" )  and ("l" and ( not "m") )  )  and "n" )  and ("o" and "p" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Aryl OR Carboxylic acid OR Pyrazine by Organic Functional groups ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Aryl OR Carboxylic acid OR Overlapping groups OR Pyrazine by Organic Functional groups (nested) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Acid, aromatic attach [-COOH] OR Alcohol, olefinic attach [-OH] OR Aromatic Carbon [C] OR Aromatic Nitrogen OR Carbonyl, olefinic attach [-C(=O)-] OR Carbonyl, one aromatic attach [-C(=O)-] OR Miscellaneous sulfide (=S) or oxide (=O) OR Olefinic carbon [=CH- or =C<] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Aromatic compound OR Carbonic acid derivative by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as No alert found by DNA binding by OASIS v.1.3

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as SN2 OR SN2 >> Direct acting epoxides formed after metabolic activation OR SN2 >> Direct acting epoxides formed after metabolic activation >> Quinoline Derivatives OR SN2 >> SN2 at an activated carbon atom OR SN2 >> SN2 at an activated carbon atom >> Quinoline Derivatives by DNA binding by OASIS v.1.3

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as No alert found by DNA binding by OECD

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Michael addition OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Arenes OR Michael addition >> Polarised Alkenes-Michael addition OR Michael addition >> Polarised Alkenes-Michael addition >> Alpha, beta- unsaturated esters by DNA binding by OECD

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as No alert found by Carcinogenicity (genotox and nongenotox) alerts by ISS

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Hydrazine (Genotox) OR Metals, oxidative stress (Nongenotox) OR o-phenylphenol (Nongenotox) OR Structural alert for genotoxic carcinogenicity OR Structural alert for nongenotoxic carcinogenicity by Carcinogenicity (genotox and nongenotox) alerts by ISS

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Bioavailable by Lipinski Rule Oasis ONLY

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Non-Metals by Groups of elements

Domain logical expression index: "m"

Referential boundary: The target chemical should be classified as Alkali Earth OR Halogens OR Metals OR Transition Metals by Groups of elements

Domain logical expression index: "n"

Similarity boundary:Target: OC(=O)c1cnccn1
Threshold=20%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "o"

Parametric boundary:The target chemical should have a value of log Kow which is >= -0.772

Domain logical expression index: "p"

Parametric boundary:The target chemical should have a value of log Kow which is <= 0.802

Validity criteria fulfilled:

not specified

Conclusions:

The short term toxicity on Danio rerio (fish) was predicted for Pyrazine-2-carboxylic acid using OECD QSAR toolbox version 3.4 and LC50 value was estimated to be 116.63 mg/l on Danio rerio for 96 hrs duration considering mortality effects.

Executive summary:

Using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the six closest read across substances, the short term toxicity on fish was predicted for Pyrazine-2-carboxylic acid (Cas no. 98-97-5). Lethal concentration i.e LC50 value was estimated to be 116.63 mg/l for Danio rerio for 96 hrs duration. Based on the effect value, Pyrazine-2-carboxylic acid (Cas no. 98-97-5) was non toxic to fish, hence it can be considered to be not classified as per the CLP classification criteria for aquatic environment.

Description of key information

Using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the six closest read across substances, the short term toxicity on fish was predicted for Pyrazine-2-carboxylic acid (Cas no. 98-97-5). Lethal concentration i.e LC50 value was estimated to be 116.63 mg/l for Danio rerio for 96 hrs duration. Based on the effect value, Pyrazine-2-carboxylic acid (Cas no. 98-97-5) was non toxic to fish, hence it can be considered to be not classified as per the CLP classification criteria for aquatic environment.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

116.63 mg/L

Additional information

Two studies from prediction reports and experimental study from authorative database for short term fish toxicity endpoint for test chemical Pyrazine-2-carboxylic acid (Cas no. 98-97-5) with relevant read across which is close to target using Log Kow as descriptor were reviewed as follows:

 

Using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the five closest read across substances, the short term toxicity to fish was predicted for Pyrazine-2-carboxylic acid (Cas no. 98-97-5) . LC50 value was estimated to be 116.63 mg/L on Danio rerio (previous name: Brachydanio rerio) for 96 hrs duration. Based on this value it can be concluded that the Pyrazine-2-carboxylic acid can be considered as non toxic to fish at environmentally relevant concentrations.

Above prediction assist by experimental study for read across chemical Pyridine (Cas no. 110-86-1) from authorative database Japan chemicals collborative knowledge database (J-check); 2017 In acute toxicity test of Pyridine to Oryzias latipes according to OECD Guideline 203 (Fish, Acute Toxicity Test) in freshwater condition for 96 hrs.During experiment the lethal concentration (LC50) was determined to be >100 mg/l.

Both studies for target and read across substance indicate that the chemical is likely to be non toxic to fish with lethal concentration range >100-116.63 mg/l. Thus, based on the available information, the test substance Pyrazine-2-carboxylic acid (Cas no. 98-97-5) can be considered as non toxic to aquatic environment and thus not classified in aquatic environment as per the CLP criteria.