2-hydroxypyridine 1-oxide

Endpoint summary

Description of key information

Short term toxicity to aquatic invertebrates:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the six closest read across substances, toxicity on Daphnia magna was predicted for 2-Hydroxypyridine 1-oxide (13161-30-3).The EC50 value was estimated to be 180.94 mg/l when 2-Hydroxypyridine 1-oxide was exposed to Daphnia magna for 48hrs.

Toxicity to aquatic algae and cyanobacteria:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the six closest read across substances, the toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for Target substance 2-Hydroxypyridine 1-oxide (13161-30-3) EC50 value was estimated to be 158.0.54 mg/l for Species Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) for 72 hrs duration when exposed to 2-Hydroxypyridine 1-oxide.

Based on this value it can be concluded that the substance 2-Hydroxypyridine 1-oxide is considered as not toxic to aquatic environment as per the criteria mentioned in CLP regulation. 

Additional information

Toxicity of the chemical 2-Hydroxypyridine 1-oxide (13161-30-3) on the growth and other activity of aquatic invertebrates and algae was studied by considering and collecting the data from various databases for target chemical and also for some RA (read across) chemicals.

Short term toxicity to aquatic invertebrates:

The toxicity of the chemical 2-Hydroxypyridine 1-oxide (13161-30-3) on the growth of aquatic invertebrates was studied by considering and collecting the data from various databases for target chemical. Some RA (read across) chemicals were also studied. The result are summarised as below:

In the first weight of evidence study for 2-Hydroxypyridine 1-oxide (13161-30-3) based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the six closest read across substances, toxicity on Daphnia magna was predicted for 2-Hydroxypyridine 1-oxide (13161-30-3).The EC50 value was estimated to be 180.94 mg/l when 2-Hydroxypyridine 1-oxide was exposed to Daphnia magna for 48hrs.

 

In the second weight of evidence study for target chemical 2-Hydroxypyridine 1-oxide (13161-30-3) ECOSAR, 2017. Based on the prediction done by EPI suite, ECOSAR version 1.1, on the basis of similarity of structure to chemicals for which the aquatic toxicity has been previously measured by structure-activity relationships (SARs) program, the LC 50 value for short term toxicity to aquatic invertebrates was predicted. On the basis of this program, the LC 50 value for short term toxicity to aquatic invertebrates was predicted to be 22147 mg/l 2- Hydroxy -pyridine 1-oxide in 48 hrs. Based on this value it can be concluded that the substance is considered to be not toxic to aquatic environment and cannot be classified as toxic as per the criteria mentioned in CLP regulation.

 

Similarly in the third weight of evidence study for RA chemical (108-80-5) J-check, Short-term toxicity study of Isocyanuric acid on the mobility of aquatic invertebrates for 48 hrs. Test was performed in static conditions. Based on the immobilization of daphnia due to Isocyanuric acid, the EC50 was 1000mg/l. Based on the EC50 value, the chemical Isocyanuric acid was not toxic and can be consider to be classified as nontoxic as per the CLP classification criteria.

 

Similarly in the fourth weight of evidence study for another RA chemical 123-33-1 (1,2-Dihydro-3,6-pyridazinedione) from HSDB and ECOTOX, 2017, Short term toxicity of Maleic hydrazide (1,2-Dihydro-3,6-pyridazinedione) on the growth of daphnia magna was studied for 48 hrs. Test was performed by static system on 1 ins age of fish. Based on the intoxication of daphnia magna by the exposure of Maleic hydrazide (1,2-Dihydro-3,6-pyridazinedione) the EC50 was 107.5 mg/l. Based on the EC50 value Maleic hydrazide (1,2-Dihydro-3,6-pyridazinedione) was not toxic and cannot be consider as classified as toxic to aquatic environment as per the CLP classification criteria.

Based on the data from various sources, it can be concluded that the substance 2-Hydroxypyridine 1-oxide is likely to be not toxic at environmentally relevant concentrations and can be considered as 'not classified' as per the criteria mentioned in CLP regulation.

 

Toxicity to aquatic algae and cyanobacteria:

The toxicity of the chemical 2-Hydroxypyridine 1-oxide (13161-30-3) on the growth of aquatic algae was studied by considering and collecting the data from various databases for target chemical. Some RA (read across) chemicals was also studied. The results are summarised as below:

 

In the first weight of evidence study for 2-Hydroxypyridine 1-oxide (13161-30-3) based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the six closest read across substances, the toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for Target substance 2-Hydroxypyridine 1-oxide (13161-30-3). EC50 value was estimated to be 158.0.54 mg/l for Species Pseudokirchneriella subcapitata for 72 hrs duration when exposed to 2-Hydroxypyridine 1-oxide. Based on this value it can be concluded that the substance 2-Hydroxypyridine 1-oxide is considered as not toxic to aquatic environment as per the criteria mentioned in CLP regulation. 

 

In the second weight of evidence study for target chemical 2-Hydroxypyridine 1-oxide (13161-30-3) ECOSAR, 2017, Based on the prediction done using the EPI Suite ECOSAR version 1.11, the short term toxicity on green algae was predicted for test substance pyridin-2-ol 1-oxide (13161 -30 -3). On the basis of effects observed in a static freshwater system, the effect concentration EC50 value for the substance is estimated to be 5117 mg/l for green algae for 98 hrs duration. Based on this value, it can be concluded that the test chemical pyridin-2-ol 1-oxide can be considered as non-toxic to green algae at environmentally relevant concentrations and can be considered not-classified as toxic as per the CLP classification criteria.

 

Similarly in the third weight of evidence study for RA chemical (108-80-5) J-check and HSDB, 2017, Short term toxicity study of Isocyanuric acid (IUPAC name 1,3,5-Triazin-2,4,6-triol )on the growth of freshwater green algae was carried out for 72 hrs. The effective concentration (EC50) value of aquatic green algae in a 72 hr study on the basis of growth rate effect and AUG was 950 mg/l and 620 mg/l. But the NOEC on the basis of growth rate AUG and was 250 mg/l and 22 mg/l. Based on the growth rate and AUG of green algae by considering EC50, Isocyanuric acid (IUPAC name 1,3,5-Triazin-2,4,6-triol ) was nontoxic and cannot be classified as toxic to aquatic algae as per the CLP classification criteria.

 

Similarly in the fourth weight of evidence study for RA chemical (108-80-5) from IUCLID dataset Short term toxicity study of Isocyanuric acid (IUPAC name 1,3,5-Triazin-2,4,6-triol )on the growth of freshwater green algae Selenastrum capricornutums was carried out for 96 hrs. The effective concentration (EC50) value of aquatic green algae in a 96 hr. study on the basis of biomass was 712 mg/l, but the NOEC and LOEC on the basis of biomass was ≤ 100 mg/l and 320 mg/l. Based on the inhibition of biomass of green algae by considering EC50, cyanuric acid (IUPAC name 1,3,5-Triazin-2,4,6-triol ) was nontoxic and cannot be classified as toxic to aquatic algae as per the CLP classification criteria.

Based on this value it can be concluded that the substance 2-Hydroxypyridine 1-oxide is likely to be non toxic to aquatic algae at environmentally relevant concentrations and can be considered as 'not classified' as per the criteria mentioned in CLP regulation. 

Based on the data from various sources for invertebrates and algae, it can be concluded that the substance 2-Hydroxypyridine 1-oxide is considered to be not toxic to aquatic environment and can be classified as non-toxic as per the criteria mentioned in CLP regulation.