Potassium O-pentyl dithiocarbonate

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:

comparable to guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

no

Test organisms (species):

Chlorella pyrenoidosa

Details on test organisms:

SPECIES #
(NAME): 426 Chlorella pyrenoidosa (Green Algae)
AGE: NR NR
LIFE STAGE: not reported, unknown
COMMENT: 10E+8 CELLS/100 ML

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

90 mg CaCO3/L

Test temperature:

20 ± 1 °C

pH:

8.7 ± 0.2

Dissolved oxygen:

NR

Salinity:

NR

Details on test conditions:

The test was carried out in sealed flasks to prevent evaporation of CS2.
The medium contained major salts, urea, Ca-glycerophosphate, dextrose and trace elements. The complete composition of the test medium is given in Van Leeuwen and Maas, Environ. Pollution A37: 105-115 (1985).
The starting density of the cells was 1E5 cells/mL. The volume of test medium was 100 mL per flask. The medium was shaken under fluorescent light (7.5 W/m2).

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

21 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

55.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: On a molecular weight scaled basis, the EC50 would be 55.8 mg/l. (21 x 202.37) /76.13 =55.8 mg/l

Details on results:

Potassium amyl xanthate readily decomposes to carbon disulphide, especially in the presence of moisture/water. Therefore, the health effects of carbon disulphide (CS2) need to be considered in the assessment of potassium amyl xanthate.
On a molecular weight scaled basis, the EC50 would be 55.8 mg/l. (21 x 202.37) /76.13 =55.8 mg/l

Reported statistics and error estimates:

no data

Validity criteria fulfilled:

yes

Conclusions:

The 96-h EC50 of CS2 for the alga Chlorella pyrenoidosa in sealed flasks was 21 mg/L, based on the inhibition of growth rate.
Potassium amyl xanthate readily decomposes to carbon disulphide, especially in the presence of moisture/water. Therefore, the health effects of carbon disulphide (CS2) need to be considered in the assessment of potassium amyl xanthate.
On a molecular weight scaled basis, the EC50 would be 55.8 mg/l. (21 x 202.37) /76.13 =55.8 mg/l

Executive summary:

Potassium amyl xanthate readily decomposes to carbon disulphide, especially in the presence of moisture/water. Therefore, the health effects of carbon disulphide (CS2) need to be considered in the assessment of potassium amyl xanthate.

On a molecular weight scaled basis, the EC50 would be 55.8 mg/l. (21 x 202.37) /76.13 =55.8 mg/l

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

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 model

Principles of method if other than guideline:

ECOSAR Program(v1.00)

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

other: QSAR model

Details on test organisms:

not applicable. QSAR model

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:

100% Potassium amyl xanthate (CAS No. 2720-73-2)
SMILES : S=C(S(K))OCCCCC
CHEM : Carbonodithioic acid, O-pentyl ester, potassium salt
MOL FOR: C6 H11 O1 S2 K1
MOL WT : 202.37
Log Kow: 2.34 (KowWin estimate)
Wat Sol: 655.8 mg/L (WskowWin estimate)

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

20.725 mg/L

Nominal / measured:

not specified

Conc. based on:

not specified

Basis for effect:

not specified

Duration:

30 d

Dose descriptor:

NOEC

Effect conc.:

8.382 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 = 20.725 mg/L (ppm)
Green Algae, 30-day, NOEC cited as a ChV value = 8.382 mg/L(ppm)

Overview of QSARs estimations on aquatic toxicity of  Potassium amyl xanthate

to Green algae

Method	Results	Remarks	Reference
QSAR estimate	Green Algae, 96-hr EC50 = 20.725 mg/L (ppm) Green Algae, 30-day, NOEC cited as a ChV value = 8.382 mg/L(ppm)	Reliable with restrictions, QSAR estimated data	ECOSAR Program (v1.00)

 

 Green Algae, 96-hr EC50 = 20.725 mg/L (ppm)

Green Algae, 30-day, NOEC cited as a ChV value = 8.382 mg/L(ppm)

Validity criteria fulfilled:

yes

Remarks:

method for chemicals properties assessment.

Conclusions:

Green Algae, 96-hr EC50 = 20.725 mg/L (ppm)
Green Algae, 30-day, NOEC cited as a ChV value = 8.382 mg/L(ppm)

Executive summary:

The ECOSAR QSAR model predicts that 30-day, NOEC cited as a ChV value would to be 8.382 mg/L (ppm) Green Algae.

The ECOSAR QSAR model predicts that 96-hr EC50 value would to be 20.725 mg/L (ppm) for Green Algae.

Reference 3

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

Justification for type of information:

Amyl Alcohol ( 1-pentyl alcohol) is both reagents used in the manufacture, as well as decomposition products of xanthates. Therefore, the health effects of Amyl Alcohol ( 1-pentyl alcohol) need to be considered in the assessment of potassium amyl xanthate.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Principles of method if other than guideline:

cell growth inhibition test

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Scenedesmus quadricauda

Details on test organisms:

BREEDING OF TEST ORGANISMS
- species: Scenedesmus quadricauda
- 100 ml Erlenmeyer flask with 20 ml nutrient solution
- relative humidity 50 %
- renewal of preparatory culture every 10 days
- temperature 27 °C
- illuminated permanent and protected against daylight

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

8 d

Test temperature:

27 deg C

pH:

pH: adjusted to pH 7

Details on test conditions:

TEST PROCEDURE
- test vessels: Kabsenberg test tubes
- test volume: 10 ml
- pH: adjusted to pH 7
- daily shaken
- temperature: 27 °C
- cell culture: 5 ml algae suspension per test flask (turbidity 20 formazine nephelometric units)
- number of replicates: 3
- measurement of extinction: Hg 578 nm
- test criterion: cell multiplication inhibition (calculated by measuring the extinction)

Reference substance (positive control):

no

Duration:

8 d

Dose descriptor:

EC5

Effect conc.:

260 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: cell multiplication inhibition (calculated by measuring the extinction)

Duration:

8 d

Dose descriptor:

other: TTC (toxic threshold concentration) = TGK (Toxische Grenzkonzentration) which is comparable with EC5

Effect conc.:

260 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

A 8d EC5 of 260 mg/L has been determined for the effects of the test substance (Amyl Alcohol ) on growth rate effect of the Scenedesmus quadricauda .

Validity criteria fulfilled:

yes

Conclusions:

A 8d EC5 of 260 mg/L has been determined for the effects of the test substance (Amyl Alcohol ) on growth rate effect of the Scenedesmus quadricauda .
Amyl Alcohol ( 1-pentyl alcohol) is both reagents used in the manufacture, as well as decomposition products of xanthates. Therefore, the health effects of Amyl Alcohol ( 1-pentyl alcohol) need to be considered in the assessment of potassium amyl xanthate.

Executive summary:

A 8d EC5 of 260 mg/L has been determined for the effects of the test substance (Amyl Alcohol ) on growth rate effect of the Scenedesmus quadricauda .

Amyl Alcohol ( 1-pentyl alcohol) is both reagents used in the manufacture, as well as decomposition products of xanthates. Therefore, the health effects of Amyl Alcohol ( 1-pentyl alcohol) need to be considered in the assessment of potassium amyl xanthate.

Reference 4

Endpoint:

toxicity to aquatic algae and cyanobacteria

Data waiving:

other justification

Justification for data waiving:

other:

Description of key information

The ECOSAR QSAR model predicts that 30-day, NOEC cited as a ChV value would to be 8.382 mg/L (ppm) Green Algae.
The ECOSAR QSAR model predicts that 96-hr EC50 value would to be 20.725 mg/L (ppm) for Green Algae.

Key value for chemical safety assessment

EC50 for freshwater algae:

20.725 mg/L

EC50 for marine water algae:

2.07 mg/L

EC10 or NOEC for freshwater algae:

8.382 mg/L

EC10 or NOEC for marine water algae:

0.84 mg/L

Additional information

The ECOSAR QSAR model predicts that 30-day, NOEC cited as a ChV value would to be 8.382 mg/L (ppm) Green Algae.

The ECOSAR QSAR model predicts that 96-hr EC50 value would to be 20.725 mg/L (ppm) forGreen 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 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