Dipotassium oxide

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

other: Published data

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

Diatoms were cultured in synthetic dilution water under controlled conditions. Tests were made by putting standard inoculum of cells in each of the
150 ml Erlenmeyer flasks, and comparing the number of cells produced at the end of a 5-day period. A graded series of test concentrations were used.

GLP compliance:

not specified

Analytical monitoring:

yes

Vehicle:

yes

Details on test solutions:

Diatoms were cultured in synthetic dilution water under controlled conditions. Tests were made by putting standard inoculum of cells in each of the
150 ml Erlenmeyer flasks, and comparing the number of cells produced at the end of a 5-day period. A graded series of test concentrations were used.

Test organisms (species):

Nitscheria linearis

Details on test organisms:

Nitscheria linearis (diatom)

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

120 h

Hardness:

10 mg/L CaCO3

Test temperature:

22 °C

Dissolved oxygen:

5 to 9 mg/L

Duration:

120 h

Dose descriptor:

EC50

Effect conc.:

1 337 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

Toxicity to aquatic algae and cyanobacteria was determined with Nitscheria linearis (diatom) and was determined as 120h-EC50 = 1337mg/L

Validity criteria fulfilled:

not specified

Conclusions:

Toxicity to aquatic algae and cyanobacteria was determined with Nitscheria linearis (diatom) and was determined as 120h-EC50 = 1337mg/L

Reference 2

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:

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:

QSAR prediction: US EPA accepted QSAR method for chemicals properties assessment.

Qualifier:

according to guideline

Guideline:

other: QSAR model

Principles of method if other than guideline:

ECOSAR Program(v1.00)

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

other: Green Algae

Details on test organisms:

QSAR model-Green Algae

Test type:

other: QSAR model

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

not applicable. QSAR model

pH:

not applicable. QSAR model

Dissolved oxygen:

not applicable. QSAR model

Salinity:

not applicable. QSAR model

Nominal and measured concentrations:

not applicable. QSAR model

Details on test conditions:

-Name of test material (as cited in study report:Potassium oxide
CAS Number: 12136-45-7
SMILES : KOK
CHEM : Potash (potassium oxide)
MOL FOR: O1 K2
MOL WT : 94.20
Values used to Generate ECOSAR Profile

Log Kow: -1.380 (EPISuite Kowwin v1.68 Estimate)
Wat Sol: 1E+006 (mg/L, EPISuite WSKowwin v1.43 Estimate)

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

1 368.296 mg/L

Nominal / measured:

not specified

Conc. based on:

not specified

Basis for effect:

not specified

Duration:

30 d

Dose descriptor:

NOEC

Effect conc.:

178.832 mg/L

Nominal / measured:

not specified

Conc. based on:

not specified

Basis for effect:

not specified

Remarks on result:

other: NOEC cited as a ChV value

Details on results:

Green Algae, 96-hr EC50 =1368.296 mg/L (ppm)
Green Algae, 30-day, NOEC cited as a ChV value = 178.832 mg/L(ppm)

Overview of QSARs estimations on aquatic toxicity of Dipotassium oxide/Potassium oxide to Green algae

 

Method	Results	Remarks	Reference
QSAR estimate	Green Algae, 96-hr EC50 =1368.296 mg/L (ppm) Green Algae, 30-day, NOEC cited as a ChV value = 178.832 mg/L(ppm)	Reliable with restrictions, QSAR estimated data	ECOSAR Program (v1.00)

 Green Algae, 96-hr EC50 =1368.296 mg/L (ppm)

Green Algae, 30-day, NOEC cited as a ChV value = 178.832 mg/L(ppm)

Validity criteria fulfilled:

yes

Remarks:

method for chemicals properties assessment.

Conclusions:

Green Algae, 96-hr EC50 =1368.296 mg/L (ppm)
Green Algae, 30-day, NOEC cited as a ChV value = 178.832 mg/L(ppm)

Executive summary:

The ECOSAR QSAR model predicts that 30-day, NOEC cited as a ChV value would to be 178.832 mg/L (ppm) Green Algae.

The ECOSAR QSAR model predicts that 96-hr EC50 value would to be 1368.296 mg/L (ppm) for Green Algae.

Description of key information

Toxicity to aquatic algae and cyanobacteria was determined with Nitscheria linearis (diatom) and was determined as 120h-EC50 = 1337 mg/L
The ECOSAR QSAR model predicts that 30-day, NOEC cited as a ChV value would to be 178.832 mg/L (ppm) Green Algae.
The ECOSAR QSAR model predicts that 96-hr EC50 value would to be 1368.296 mg/L (ppm) for Green Algae.
 
The available data for saltwater algae and cyanobacteria are limited and to obtaine the value for PNECs for saltwaters is taken account a assesment factor 10 to extrapolate to EC50/NOEC following the “Guidance on Information Requirement and Chemical Safety Assessment R.10: Characterisation of dose [concentration]- response for environment”and “Table R.10-5 Assessment factors proposed for deriving PNEC water for saltwater for different data sets”, to account for the possibility that greater taxonomic diversity in the marine environment makes it likely that some marine taxa may be more sensitive than the most sensitive freshwater taxa

Key value for chemical safety assessment

EC50 for freshwater algae:

1 337 mg/L

EC50 for marine water algae:

133.7 mg/L

EC10 or NOEC for freshwater algae:

178.832 mg/L

EC10 or NOEC for marine water algae:

17.88 mg/L

Additional information

Toxicity to aquatic algae and cyanobacteria was determined with Nitscheria linearis (diatom) and was determined as 120h-EC50 = 1337 mg/L

The ECOSAR QSAR model predicts that 30-day, NOEC cited as a ChV value would to be 178.832 mg/L (ppm) Green Algae.

The ECOSAR QSAR model predicts that 96-hr EC50 value would to be 1368.296 mg/L (ppm) for Green Algae.

 

The available data for saltwater algae and cyanobacteria are limited and to obtaine the value for PNECs for saltwaters is taken account a assesment factor 10 to extrapolate to EC50/NOEC following the “Guidance on Information Requirement and Chemical Safety Assessment R.10: Characterisation of dose [concentration]- response for environment”and “Table R.10-5 Assessment factors proposed for deriving PNEC water for saltwater for different data sets”, to account for the possibility that greater taxonomic diversity in the marine environment makes it likely that some marine taxa may be more sensitive than the most sensitive freshwater taxa