Dipotassium oxide

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

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

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

other: Labeo rohita

Details on test organisms:

SPECIES #
(NAME): 202 Labeo rohita (Rohu)
AGE: NR
LIFE STAGE: not reported, unknown
COMMENT: 0.985 G

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

NR

Test temperature:

21 to 25 °C

pH:

between pH 7.5 and 9.0.

Dissolved oxygen:

Saturated mg/l

Salinity:

SALINITY:NR

Nominal and measured concentrations:

TYPE VALUE RANGES STANDARD CONC (ug/L ) IONCIC FRACTION
F 917600 910200 TO 925200 917600 (910200-925200) ug/L Ni

Details on test conditions:

TEST CONDITIONS
STUDY TYPE:
MEDIA: FW (Fresh water)
LOCATION: LAB (Laboratory, indoor)
CONTROL: S (sufficient control)
EXPOSURE TYPE: R ( semi-static)
APPLICATION FREQ.: NR
EXPOSURE DUR.: 96 hour(s)
STAND DUR. (D): 4 day(s
TEST CONCENTRATION
CHEM ANAL. METHOD: unmeasured
UNIT OF MEASURE: ug/L micrograms per liter

TYPE VALUE RANGES STANDARD CONC (ug/L ) IONCIC FRACTION
TYPE VALUE RANGES STANDARD CONC (ug/L ) IONCIC FRACTION
F 917600 910200 TO 925200 917600 (910200-925200) ug/L Ni

WATER QUALITY VALUE RANGE (UNIT)
TEMPERATURE: NR 21 TO 25 C
pH: NR 7.5 TO 9.0
HARDNESS: NR NR TO NR mg/L CaCO3
SALINITY: NR NR TO NR
ALKALINITY: NR NR TO NR NR
CONDUCTIVITY: NR NR TO NR NR
DISSOLVED OXYGEN: SAT NR TO NR mg/l
ORGANIC CARBON (NR): NR NR TO NR NR

Reference substance (positive control):

not specified

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

917.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Under the conditions of the present test Potassium oxide induced no mortality in Labeo rohita (Rohu) below 183.52 mg/l (NOEC). One of the 96h-LC50 was 917.6 mg/l

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

939.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 904.5mg/l to 976.4 mg/l

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

965.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 939.4mg/l to 992.9mg/l

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

928.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 923.7 mg/l to 934.2 mg/l

Details on results:

EFFECT RESULTS
EFFECT: Mortality
TREND: NR
RESPONSE SITE:NR
% EFFECT: NR
EFFECT MEASUREMENT:Mortality

ENDPOINT
ENDPOINT: Lethal concentration to 50% of test organisms
ENDPOINT ASSIGN.: X
SIGNIFICANCE: NA
LEVEL: NA
BCF Value (F): NR ( NR to NR)

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the present test Potassium oxide induced no mortality in Labeo rohita (Rohu) below 183.52 mg/l (NOEC). One of the 96h-LC50 was 917.6 mg/l

Reference 2

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 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

Principles of method if other than guideline:

EPI Suite v 4.1/ECOSARv1.00

GLP compliance:

no

Remarks:

not applicable to QSAR models

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

other: Fishes species

Details on test organisms:

no further information

Test type:

other: QSAR model

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

not applicable. QSAR model

Test temperature:

not applicable. QSAR model

pH:

not applicable. QSAR model

Dissolved oxygen:

not applicable. QSAR model

Salinity:

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:

LC50

Effect conc.:

16 062.827 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: (Q)SAR prediction

Remarks on result:

other: non-toxic as determined by (Q)SAR

Details on results:

A 96 h LC50 value of 16062.827 mg/L has been calculated for the effects of the test substance on the mortality of the fish taxonomic group. This result signifies that the test substance is not expected to be toxic.
A reliable 96 h LC50 value of 16062.827 mg/L has been calculated for the effects of the test substance towards fish taxonomic group.Therefore the test substance has been predicted to be non toxic.

Results with reference substance (positive control):

A 96 h LC50 value of 16062.827 mg/L has been calculated for the effects of the test substance on the mortality of the fish taxonomic group. This result signifies that the test substance is not expected to be toxic.

Validity criteria fulfilled:

yes

Remarks:

US EPA accepted QSAR method for chemicals properties assessment.

Conclusions:

A 96 h LC50 value of 16062.827 mg/L has been calculated for the effects of the test substance on the mortality of the fish taxonomic group. This result signifies that the test substance is not expected to be toxic.
A reliable 96 h LC50 value of 16062.827 mg/L has been calculated for the effects of the test substance towards fish taxonomic group.Therefore the test substance has been predicted to be non toxic.

Executive summary:

The ECOSAR QSAR model predicts that the 96hr LC50 for freshwater fish would to be 16062.827 mg/l .This result signifies that the test substance is not expected to be toxic.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

other: Published data

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Justification for type of information:

Test procedure in accordance with national standard methods with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Principles of method if other than guideline:

Toxicity tests followed the general guidance of the U.S. Environmental Protection Agency (USEPA) for conducting acute whole effluent toxicity tests:
U.S. Environmental Protection Agency. 1991. Methods for measuring the acute toxicity of effluents to freshwater and marine organisms, 4th ed. EPA/600/4-90/027. Cincinnati, OH.
and
U.S. Environmental Protection Agency. 1991. Methods for aquatic toxicity identification evaluations. Phase I toxicity characterization procedures, 2nd ed. EPA/600/6-91/003. Washington, DC.
The EPA test methods are in most parts equivalent or similar to OECD Guideline 203.

GLP compliance:

not specified

Analytical monitoring:

yes

Details on sampling:

Dissolved oxygen (DO) and pH were measured in selected test solutions during actual toxicity testing, primarily on solutions near the threshold for acute toxicity.

Vehicle:

not specified

Details on test solutions:

Test solutions were prepared by dissolving individual ion salts in moderately hard reconstituted water.

Test organisms (species):

Pimephales promelas

Details on test organisms:

Test organisms were obtained from in-house cultures (ENSR, Fort Collins, CO, USA); fathead minnows were 1 to 7 d old. Fathead minnow brood stock were cultured at 20 to 25°C in tap water that was pretreated with activated carbon. Eggs and larva were held in moderately hard reconstituted water; larva were fed brine shrimp nauplii (Artemia sp.) twice daily until they were used in testing.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

not applicable

Hardness:

no data

Test temperature:

21 to 25 °C

pH:

Measured pH varied according to the components of the solution (several inorganic salts were tested in this study) but is generally given to be between pH 7.5 and 9.0.

Dissolved oxygen:

Measured DO concentrations were always within an acceptable range (> 40% saturation).
Reference: U.S. Environmental Protection Agency. 1991. Methods for measuring the acute toxicity of effluents to freshwater and marine organisms, 4th ed. EPA/600/4-90/027. Cincinnati, OH.

Salinity:

no data

Nominal and measured concentrations:

Test solution of potassium chloride was prepared by serially diluting a 10,000-mg/L stock solutions with MHRW to develop a series of test concentrations spaced on a 0.5 x dilution factor (i.e., 10,000, 5,000, 2,500, 1,250 mg/L). As testing proceeded and effect thresholds were determined, test concentrations were often spaced much more closely (e.g., 2,500, 2,000, 1,500, 1,000, 500 mg/L) to better define responses near the effect threshold.

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

880 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

910 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mortality (fish)

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

950 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mortality (fish)

Details on results:

Effect range is given from n=3 tests as >= 750 -<= 1020 mg/L. The arithmetic mean is given as 880 mg/L.

Sublethal observations / clinical signs:

- Ion concentrations in the stock solution differed less than 20% from nominal concentrations (exact values not given) and, thus, nominal concentrations were used to give the result.

- Several inorganic salts were tested in this study and the following is given but does not detail if this information is relevant for potassium chloride:

In some analyses, the measured concentrations of cations and anions (expressed as milliequivalents or meq) in a salt solution were not similar. Because charge balance is a physical/chemical requirement, such solutions were further evaluated to determine which concentration (cation or anion) was closer to the nominal value. In all cases, the cation concentration was closer to the nominal value; based on this, the anion concentration in the stock solution was changed to the concentration (in meq) of the corresponding cation.

- To calculate ion concentrations in actual test solutions, the concentrations in the applicable stock solutions were multiplied by the relative proportion of each solution in the test solution. Because the dilution water (MHRW) also contained small concentrations of each ion, these background concentrations were then added to the calculated contributions from the stock solutions.

Validity criteria fulfilled:

not specified

Conclusions:

The publication of Mount et al. (1997) appears to be well documented and, thus, allows evaluation of the study. The study is reliable although validity criteria as given by OECD 203 are not fulfilled each or there is no data. As an example dissolved oxygen is reported to be > 40 %. However, several salts have been assessed and it is not indicated if dissolved oxygen was minor in the test with potassium chloride. In the worst case the reported effect would be lower than if caused by the test item which would result in a overestimation of the toxic effect.

Executive summary:

Short-term toxicity of potassium chloride to fish (Pimephales promelas) was assessed according to US EPA methods (EPA/600/4-90/027, EPA/600/6-91/003) that are equivalent or similar to OECD 203 method and is given as 96 hour-LC50 = 880 mg/L (Mount, 1997).

Description of key information

Under the conditions of the study of Palanisamy,R., and G. Kalaiselvi,1992, 96h-LC50 was 917.6 mg/l.
One of the 96h-LC50 with Potassium oxide was 917.6 mg/l 
The ECOSAR QSAR model predicts that the 96hr LC50 for freshwater fish would to be 16062.827 mg/l .This result signifies that the test substance is not expected to be toxic to fishes.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

917.6 mg/L

Marine water fish

Marine water fish

Effect concentration:

91.76 mg/L

Additional information

Under the conditions of the study of Palanisamy,R., and G. Kalaiselvi,1992, 96h-LC50 was 917.6 mg/l.

One of the 96h-LC50 with Potassium oxide was 917.6 mg/l

The ECOSAR QSAR model predicts that the 96hr LC50 for freshwater fish would to be 16062.827 mg/l .This result signifies that the test substance is not expected to be toxic to fishes.

The available data for saltwater fishes are limited and to obtaine the value for PNECs for saltwaters is taken account a assesment factor 10 to extrapolate to LC50 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