Cesium formate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1995

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

1. The test was conducted according to a guidance still under development (PARCOM guidance) and no mention of GLP practice is made. 2. Defined information were provided on: - Test material identity and purity - Test species details (source, culture of test species, age) - Study design (test concentration, test medium chemistry, control, number of replicates, exposure duration). No details of analytical monitoring given. - Test observation and results with calculation of EC50 values. No details of statistics and other biological observations.

Qualifier:

according to guideline

Guideline:

other: PARCOM guidance (under development) on hazard assessment of chemicals

Deviations:

not applicable

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

yes

Details on test solutions:

The test solution was made in each individual vessel by the addition of a 1 g/stock solution into appropriate volumes of artificial seawater. No further details available.

Test organisms (species):

other: Acartia tonsa

Details on test organisms:

TEST ORGANISM
- Common name: Calanoid copepod
- Source: Vandkvslitetsinstuttet (VKI), Copenhagen, Denmark
- Age at study initiation (mean and range, SD): 17-18 d old
- Food type: Not fed during test

ACCLIMATION
- Acclimation period: No data
- Acclimation conditions (same as test or not): Acclimation conditions were closely similar to the test conditions. The copepods are maintained in 10 L glass aspirators containing artificial sea water medium, at constant temperature of 18-22 ˚C, under 16 h light/8 h dark cycle of cool fluorescent light of 1800-2100 lux illumination. Medium renewal was through a continuous flow-through system every 36 h.

- Type and amount of food: The culture was fed with mixed diet of Skeletonema costatum, Thalassiosira pseudonana, Isochysis galbana, Tetraselmis suecica.

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

None

Hardness:

No data

Test temperature:

20±2 ˚C (monitored using a mercury glass max/min thermometer)

pH:

8.2 (measured using calibrated Corning Ion Analyser 250)

Dissolved oxygen:

7.5-7.6 mg/L (measured using YSI 57 Dissolved Oxygen Meter)

Salinity:

32-33 % (measured using Salinity Refractometer)

Nominal and measured concentrations:

Nominal concentration: 10, 33, 100, 330 and 1000 mg/L
Measured concentration: No data

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): Open
- Material, size, headspace, fill volume: 140 mL glass crystalline dishes containing 100 mL of test solution
- Aeration: Aeration not done during study
- Type of flow-through (e.g. peristaltic or proportional diluter): No data
- Renewal rate of test solution (frequency/flow rate): No renewal of test solution done in the study
- No. of organisms per vessel: Ten
- No. of vessels per concentration (replicates): Three replicates
- No. of vessels per control (replicates): Three replicates
- No. of vessels per vehicle control (replicates): Not relevant
- Biomass loading rate: No data

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Artificial sea water which was prepared by dissolving artificial sea salts (Tropic Marin, Aquatechnik, Wartenberg, West Germany
- Culture medium different from test medium: Closely resembles in composition
- Intervals of water quality measurement: Water quality measured at start and at of exposure period

OTHER TEST CONDITIONS:
- Adjustment of pH: No data
- Photoperiod::8 h dark
- Light intensity: No data

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Mortality/Immobilisation
Criteria: If the animal fail to respond on touch

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 3.0 - 3.3
- Range finding study
- Test concentrations: No data on range finding study

Reference substance (positive control):

no

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

ca. 440 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limit: 380-500 mg/l

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

ca. 340 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limit: 240-480 mg/l

Cumulative mobility data:

Nominal concentration (mg/L)	No. of A. tonsa	No. of A. tonsa Immobilized 24 h     48 h
Control	31	0	0
10	30	1	1
33	29	0	0
100	30	0	1
330	30	0	13
1000	30	30	30

The test medium chemistry observed in the control and the high dose during the test were as follows:

Nominal concentration (mg/L)	Salinity (%)	pH	Dissolved oxygen (mg/L)
Control	30	8.2	7.8-7.2
1000	30	8.2-8.3	7.4-7.2

Validity criteria fulfilled:

yes

Remarks:

Validity criteria as per OECD guideline 202 was fulfilled. 1. No more than 10% control were immobilised (No immobilisation in controls). 2. Dissolved oxygen was more than 3 mg/L in control and other test vessels.

Conclusions:

Under the study conditions, the 24 and 48 h EC50 of the test substance to Acartia tonsawere determined to be 440 and 340 mg/L (nominal), respectively.

Executive summary:

A study was conducted to determine the acute toxicity of the test substance to the copepod Acartia tonsa under static conditions. The procedure was based on PARCOM guidance (under development) on hazard assessment of chemicals. Acartia tonsa (30 per dose) were exposed to the test substance monohydrate at 0, 10, 33, 100, 330 and 1000 mg/L for 48 h. Immobilisation was determined at 24 and 48 h. No analytical dose verification was conducted. Effects were observed at 10, 100, 330 and 1000 mg/L. Under the study conditions, the nominal 24 and 48 h EC50 of the test substance to Acartia tonsa were determined to be 440 and 340 mg/L, respectively (Whale, 1995).

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

From September 05, 2011 to September 20, 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

other: (1) Guidelines for the toxicity testing of substances to be submitted to the Department of Energy’s Notification Scheme for the selection of chemicals for use offshore AEP2. MAFF (Ministry of Agriculture, Fisheries and Food), Burnham on Crouch, UK.

Qualifier:

equivalent or similar to guideline

Guideline:

other: OECD 203

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Samples were collected for analyis at 0, 48 h (used and fresh) and 96 h (used and fresh).

Test organisms (species):

Crangon crangon

Details on test organisms:

TEST ORGANISM
- Common name: Brown shrimp
- Source: R Martin, Burnham-on-Crouch
- Weight at study initiation (mean and range, SD): 1.22 g
- Length at study initiation (length definition, mean, range and SD): 53 mm

ACCLIMATION
- Acclimation period: 7 days
- Acclimation conditions (same as test or not): yes

Test type:

semi-static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

15.0 - 15.5°C

pH:

8.3 - 8.6

Dissolved oxygen:

89 - 96%

Salinity:

31 - 32 pro mil

Nominal and measured concentrations:

The percentage recovery from all samples analysed was greater than 80% of nominal. According to OECD ecotoxicology test guidelines, the effect concentrations were therefore based on nominal concentrations.

Details on test conditions:

10 L volume glass aquaria with glass and mesh partitions to separate the shrimp into individual compartments to eliminate cannibalism.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

875 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

No other obvious adverse effects were observed.

Validity criteria fulfilled:

yes

Conclusions:

Under the study conditions the 96h LC50 of the test substance to brown shrimp was determined to be equivalent to 875 mg/L and the 96h NOEC 500 mg/L.

Executive summary:

A study was conducted to determine the acute toxicity of the test substance to brown shrimp (Crangon crangon) according to methods similar to MAFF and OECD guidelines, in compliance with GLP. Shrimp were exposed to the test substance to test concentrations of 62.5, 125, 250, 500 and 1000 mg/L under semi-static conditions (replacement at 48 and 96 h). The test substance was readily soluble in the dilution and the resulting test dilutions were noted as clear and colourless. Test concentrations were analysed by ICP-MS and were all found to be greater than 80% of nominal. No mortality was observed in the control tank at the end of the test period. This is within the range of mortality acceptable for validation of the test results. Under the study conditions, the 96h LC50 of the test substance to brown shrimp was determined to be equivalent to 875 mg/L and the 96h NOEC 500 mg/L (measured) (Mallett 2011).

Reference 3

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From January 12, 2011 to January 21, 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Analysis of the test concentration plus a control at test start and after 48 h of exposure. Further analysis if 100 mg/L test concentration at 0 and 48 h .
- Sample storage conditions before analysis: -20 °C

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
-Test substance was directly dissolved in water and the volume was adjusted according to the test concentration.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain: Daphnia magna
- Source: In-house laboratory culture
- Age at study initiation (mean and range, SD): 26 h old
- Method of breeding: Parthenogenesis
- Feeding during test: No

ACCLIMATION
- Acclimation period: No data
- Acclimation conditions : Yes
- Type and amount of food: Mix of algae and tetramin suspension
- Feeding frequency: 3 times a week
- Health during acclimation (any mortality observed): Yes

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

250 mg/L as CaCO3

Test temperature:

19 to 21°C

pH:

8±1

Dissolved oxygen:

101±1

Salinity:

No data

Nominal and measured concentrations:

0.1, 1, 10, 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Jars
- Type : Closed
- Material, size, headspace, fill volume: 250 ml glass jars, 200 ml of test preperation
- Aeration: No
- No. of organisms per vessel: 5 daphnids/vessel
- No. of vessels per concentration (replicates): 4 vessel/concentration
- No. of vessels per control (replicates): 4 vessel/concentration

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconsituted water
- Conductivity: <5 micro/cm
- Culture medium different from test medium: No

OTHER TEST CONDITIONS
- Adjustment of pH: Not required
- Photoperiod: 16 h light/8 h dark with 20 min dawn and dusk transition period

TEST CONCENTRATIONS
- Test concentrations: 0.1, 1, 10, 100 mg/l
- Results used to determine the conditions for the definitive study: No significant effect on immobilization at 100 mg/l

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Results with reference substance (positive control):

- EC50: For 24 h-1.9 mg/l (95% confidence limit-1.5-1.9 mg/L)
for 48 h-1.5 mg/l (95% confidence limit-1.3-1.7 mg/L)

- Other: NOEC at 24 h and 48 h is 1 mg/l

Reported statistics and error estimates:

Analysis of the immobilization data was done by the trimmed Spearman-Kaber method at 24 and 48 h using the Toxcalc computer software package.

Validity criteria fulfilled:

yes

Conclusions:

Under the test conditions, the 48 h EC50 was found to be greater than 100 mg/L (nominal).

Executive summary:

A study was conducted to determine the acute toxicity of the test substance to Daphnia magna according to OECD Guideline 202, in compliance with GLP. The test was carried out using 1st instar Daphnia magna from in-house laboratory cultures. The range of concentrations in the definitive test was determined based on a preliminary range-finding study. Both studies were performed using reconstituted water. In the range-finder, 10 daphnids/vessel (test and control) were exposed to 0.1, 1, 10 and 100 mg/L of the test substance. No significant immobilization was observed. Based on this result, a single test concentration of 100 mg/L was selected for the definitive test. Analysis of the test concentration and control was conducted at test start and after 48 h of exposure. Further analysis of the 100 mg/L test concentration was done at 0 and 48 h. No significant immobilization was observed for a period of 48 h. Under the test conditions, the 48 h EC50 was found to be greater than 100 mg/L (measured) (Vryenhoef, 2011).

Reference 4

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

From May 8, 1997 to May 12, 1997

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

A) The test was conducted according to a US Federal Register guideline but no mention of GLP is made. B) No sufficient experimental details were provided on: 1. Test system (test animal - source and number of animals per dose level) 2. Test conditions (acclimation period, diet, route of administration, vehicle, frequency of treatment) 3. Test results and observations (toxicity related data including clinical signs of toxicity, body weight, mortality, statistical results) 4. However, a definite conclusion (LC50) is mentioned

Qualifier:

according to guideline

Guideline:

other: Drilling Fluids Toxicity Test. 58 Federal Register 12507-12511, March 4, 1993

Deviations:

not applicable

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

Americamysis bahia (previous name: Mysidopsis bahia)

Test type:

not specified

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

No

Hardness:

No data

Test temperature:

20±2 ˚C

pH:

No data

Dissolved oxygen:

No data

Salinity:

20±2 %

Nominal and measured concentrations:

30,000, 60,000, 125,000, 250,000, 500,000 and 1,000,000 mg/L

Details on test conditions:

Not available

Reference substance (positive control):

yes

Remarks:

Copper sulphate

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

< 30 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Results with reference substance (positive control):

LC50 = 272 µg/mL
95 % confidence limits - 240-310 µg/mL

Reported statistics and error estimates:

Not applicable

Validity criteria fulfilled:

not specified

Conclusions:

Under the study conditions the 96 h LC50 of the test substance was lower than the lowest dose tested 30,000 mg/L (nominal).

Executive summary:

A range-finding study was conducted to determine the acute toxicity of the test substance to mysid shrimp (Mysidopsis bahia). The procedure was based on US Federal Register guidelines. Mysid shrimp were exposed to the test substance at 0, 30,000, 60,000, 125,000, 500,000 and 1,000,000 ppm (mg/L) for 96 h. Mortality and moulting incidence were determined at 3, 6, 24, 48, 72 and 96 h. No analytical dose verification was conducted. Mortality occurred at all doses, including controls, with 100% mortality at 320 mg/L. Moulting was also observed at 0, 56 and 180 mg/L. Under the study conditions, the nominal 96 h LC50 of the test substance was lower than the lowest tested dose of 30,000 mg/L (Ceron, 1997).

Reference 5

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

From October 20, 2011 to October 27, 2011

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

No analytical dose verification.

Qualifier:

according to guideline

Guideline:

other: EPA-821-R-02-014, Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms, Third Edition, October 2002

Deviations:

no

GLP compliance:

not specified

Analytical monitoring:

not specified

Test organisms (species):

Americamysis bahia (previous name: Mysidopsis bahia)

Details on test organisms:

TEST ORGANISM
- Common name: Mysid shrimp
- Source: In-house laboratory culture
- Age at study initiation (mean and range, SD):7 days

ACCLIMATION
- Acclimation period:6 days
- Acclimation conditions (same as test or not):Acclimation conditions were similar to test conditions. The test organisms were acclimated to 26+/-1 C.
- Type and amount of food:150-250 ul of standardized suspension of less than 24-hour-old Artemia nauplii, which is equal to 0.05 g wet weight strained nauplii per ml synthetic seawater
- Feeding frequency: twice daily
- Health during acclimation (any mortality observed): No data

Test type:

semi-static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

7 d

Hardness:

No data

Test temperature:

24-27°C

pH:

8±1

Dissolved oxygen:

4-7.8 mg/L

Salinity:

24-28 ppm

Nominal and measured concentrations:

Nominal concentration: 91, 151, 252, 420 and 700 mg/L
Measured concentration: No data

Details on test conditions:

TEST SYSTEM
- Test vessel: Disposable plastic cups
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: 9 cm in diameter; total volume 300 ml, test solution volume 150 ml
- Aeration: Yes on Day 4
- Renewal rate of test solution (frequency/flow rate): daily on days 1-6
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates):8
- No. of vessels per control (replicates):8
- Biomass loading rate: No data

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:Synthetic seawater prepared with hw-MARINEMIX + Bio-elements and Crystal Sea Marinemix Bioassay Laboratory Formula sea salts (80:20) and deionized water
- Culture medium different from test medium:No
- Intervals of water quality measurement:Daily

OTHER TEST CONDITIONS
- Adjustment of pH:No data
- Photoperiod:16 hrs light; 8 hrs dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :

TEST CONCENTRATIONS
- Range finding study
- Test concentrations:313, 625, 1250, 2500 and 5000 mg/l
- Results used to determine the conditions for the definitive study: IC50 for range-finding study was 424 mg/l

Reference substance (positive control):

yes

Remarks:

Potassium chloride

Key result

Duration:

7 d

Dose descriptor:

IC50

Effect conc.:

481 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95% confidence interval of 432-523 mg/l

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

521 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95% confidence interval of 485 to 565 mg/l

Key result

Duration:

7 d

Dose descriptor:

LOEC

Effect conc.:

700 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

420 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

7 d

Dose descriptor:

IC50

Effect conc.:

392 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

weight

Remarks on result:

other: 95% confidence interval of 341 to 448 mg/l

Key result

Duration:

7 d

Dose descriptor:

LOEC

Effect conc.:

420 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

weight

Key result

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

252 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

weight

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Mortality: NOEC 416 mg/l, LOEC 694 mg/l
- IC25 for survival:631mg/l

Reported statistics and error estimates:

Statistical analysis of survival data was the proportion of surviving test organisms per replicate. These proportions were transformed by the Arcsin Square Root Transformation and tested for normal distribution and homogeneity using Shapiro-Wilk's and Bartlett's tests, respectively. Growth data were not transformed. Growth data were tested for normal distribution and homogeneity using Shapiro-Wilk's and Bartlett's tests, respectively.

Validity criteria fulfilled:

yes

Conclusions:

Under the study conditions, survival and growth rate for the test substance were recorded as follows: for the survival endpoint (nominal), the IC25 was 360 mg/L, the IC50 was 481 mg/L and the 48 h LC50 was 521 mg/L. For the growth endpoint (nominal), the IC25 was 260 mg/L and the IC50 was 392 mg/L.

Executive summary:

A study was conducted to determine the acute toxicity of the test substance to Mysid shrimp (Mysidopsis bahia) according to USEPA guidance - Short Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms. Following a range-finding study, Mysid shrimp were exposed to the test substance at concentrations of 91, 151, 420 and 700 mg/L under semi-static conditions (replacement on Days 1 -6). No analytical dose verification. No mortality was observed in the control tank at the end of the test period. Under the study conditions, survival and growth rate for the test substance were recorded as follows: for the survival endpoint (nominal), the IC25 was 360 mg/L, the IC50 was 481 mg/L and the 48 h LC50 was 521 mg/L. For the growth endpoint (nominal), the IC25 was 260 mg/L and the IC50 was 392 mg/L (Daniel, 2011).

Reference 6

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1995

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

A) The test was conducted according to unpublished Shell company internal guidelines based on US EPA procedures and Paris Commission ring test results. No mention of GLP is made. 2. Adequate information on the following were not provided: a. Test organism details b. Test medium (pretreatment and quality) details c. Detailed test conditions (dose selection, analytical monitoring of test medium during the test) d. Detailed test results and other biological observations

Principles of method if other than guideline:

1. US EPA (1976) Bioassay procedures for the ocean disposal permit programme (EPA/600/9-76/010)
2. Paris Commission Ring Test, Intercallibration and comparison of tests and test laboratories for evaluation and approval of offshore chemicals and drilling muds, Water Quality Institute, Copenhagen, Denmark

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

yes

Details on test solutions:

An initial stock solution was prepared by addition of 2.5 g of the test substance into a volumetric flask made up to 250 mL by the addition of natural seawater. This stock was stirred for 1 h and then aliquots used to prepare a range of concentrations - 1, 3.2, 10, 32, 100, 320, 1000 and 3200 mg/L. No further details on test solution.

Test organisms (species):

other: Crassostrea gigas

Details on test organisms:

Common name: Pacific oyster
Source: Seasalter Shellfish Ltd., Kent
Age at study initiation (mean and range, SD): No data, embryos used in their pre-spawning state

Feeding during test: Not fed during test
Acclimation conditions (same as test or not): Same as test
Type and amount of food: Mixed diet of lsochrysis oalbana, Tetraselmis suecica, Thalassiosira pseudonana and Skeletonema costatum.
No further details available.

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

24 h

Post exposure observation period:

No

Hardness:

No data

Test temperature:

25±1 ˚C

pH:

8.1-8.2 (measured using Corning Ion Analyzer)

Dissolved oxygen:

7.3-7.6 (measured using YSI 57 Dissolved Oxygen Meter)

Salinity:

33-34 % (measured using Salinity Refractometer calibrated in the range 0-100 %)

Nominal and measured concentrations:

Nominal concentration: 1, 3.2, 10, 32, 100, 320, 1000 and 3200 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 140 mL glass crystalline dishes containing 100 mL test solution
- Type (delete if not applicable): Open
- Material, size, headspace, fill volume: 30 mL glass Beatson jars
- Aeration: No data
- Type of flow-through (e.g. peristaltic or proportional diluter): No
- Renewal rate of test solution (frequency/flow rate): Not done
- No. of organisms per vessel: 132
- No. of vessels per concentration (replicates): Four
- No. of vessels per control (replicates): Eight
- No. of vessels per vehicle control (replicates): Not relevant
- Biomass loading rate: 44 embryos/mL (calculated from the initial concentration of 3.0 x 103/mL)

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Natural sea water was used as the source of dilution water
- Intervals of water quality measurement: Water quality measured at start and end of exposure period

OTHER TEST CONDITIONS
- Adjustment of pH: No data
- Photoperiod: No data
- Light intensity: No data

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): Number of D-stage veligers observed (larvae with fully -formed symmetrical shells, and the number of larvae which failed to reach the shelled stage)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 3.2
- Justification for using less concentrations than requested by guideline: Not relevant
- Range finding study
- Test concentrations: No data on range finding study

Reference substance (positive control):

no

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

ca. 1 200 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: Abnormality in development

Remarks on result:

other: 1100-1300

Details on results:

1. Development of control embryos was as expected at 87 % (13 % abnormality) which is above the minimum limit of 60 % recommended in the test principle.
2. Percentage abnormality in test substance concentrations upto 320 mg/L ranged from between 3 to 16 %.
3. Percentage abnormal development in the 1000 and 3200 mg/L test concentrations were 44 and 99 % respectively.

Results with reference substance (positive control):

Not applicable

Results on water quality measurements:

pH, salinity, temperature and dissolved oxygen were within the desired and recommended range.

pH – 8.1-8.2

Temperature – 24.9-25.3 ˚C

Dissolved oxygen – Always greater than 60 % of the air saturated values (as recommended by US EPA)

Salinity – 33-34 %

Total count of larvae in different concentrations

Nominal concentration	Number of ‘D’ stage larvae per 2 mL	Mean	SD
Control	95, 76, 97, 85, 76, 75, 93, 93	86	9.4
1	74, 73,109, 77	83	17
3.2	91, 95, 91,91	92	2
10	84,92, 101,107	96	10
32	115, 89, 85,72	90	18
100	81, 86, 83, 112	91	14
320	80, 86, 90, 97	88	7.1
1000	56, 50, 56,57	55	3.2
3200	0, 0, 3, 1	1	1.4
Initial embryo count	90, 81, 118, 97, 76, 100, 129, 401	99	18

PNR (Percent Net Risk) values

Concentration (mg/L)	Mean ‘D’ stage	% Abnormality	PNR
Control	86	13	-
1	83	16	3
3.2	92	7	-7
10	96	3	-11
32	90	9	-5
100	91	8	-6
320	88	11	-2
1000	55	44	36
3200	1	99	99

Validity criteria fulfilled:

not specified

Conclusions:

Under the study conditions the 24 h EC50 of the test substance to Pacific oyster was determined to be 1200 mg/L (nominal).

Executive summary:

A study was conducted to determine the acute toxicity of the tests substance to Pacific oyster (Crassostrea gigas) larvae. The procedures were based on US EPA and Paris Commission recommendations. Newly fertilised pacific oyster larvae were exposed to the test substance monohydrate at 0, 1, 3.2, 10, 32, 100, 320, 1000 and 3200 mg/L for 24 h and development to the D-stage veligers was observed. No analytical dose verification was conducted. Under the study conditions the nominal 24 h EC50 of the test substance to Pacific oyster was determined to be 1200 mg/L (Whale, 1995).

Description of key information

The test substance was tested in one freshwater (water flea) and one marine (brown shrimp, mysid shrimp) invertebrate species under static or semi-static conditions according to OECD and PARCOM guidelines. The lowest L(E)C50 was determined for Daphnia magna (48h LC50 > 100 mg/L). For the marine Acartia the 48 h EC50 was determined to be 340 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Marine water invertebrates

Marine water invertebrates

Effect concentration:

340 mg/L

Additional information

A study was conducted to determine the acute toxicity of the test substance to Daphnia magna according to OECD Guideline 202, in compliance with GLP. The test was carried out using 1st instar Daphnia magna from in-house laboratory cultures. The range of concentrations in the definitive test was determined based on a preliminary range-finding study. Both studies were performed using reconstituted water. In the range-finder, 10 daphnids/vessel (test and control) were exposed to 0.1, 1, 10 and 100 mg/L of the test substance. No significant immobilization was observed. Based on this result, a single test concentration of 100 mg/L was selected for the definitive test. Analysis of the test concentration and control was conducted at test start and after 48 h of exposure. Further analysis of the 100 mg/L test concentration was done at 0 and 48 h. No significant immobilization was observed for a period of 48 h. Under the test conditions, the 48 h EC50 was found to be greater than 100 mg/L (measured) (Vryenhoef, 2011).

A study was conducted to determine the acute toxicity of the test substance to the copepod Acartia tonsa under static conditions. The procedure was based on PARCOM guidance (under development) on hazard assessment of chemicals. Acartia tonsa (30 per dose) were exposed to the test substance monohydrate at 0, 10, 33, 100, 330 and 1000 mg/L for 48 h. Immobilisation was determined at 24 and 48 h. No analytical dose verification was conducted. Effects were observed at 10, 100, 330 and 1000 mg/L. Under the study conditions, the nominal 24 and 48 h EC50 of the test substance to Acartia tonsa were determined to be 440 and 340 mg/L, respectively (Whale, 1995).

A study was conducted to determine the acute toxicity of the tests substance to Pacific oyster (Crassostrea gigas) larvae. The procedures were based on US EPA and Paris Commission recommendations. Newly fertilised pacific oyster larvae were exposed to the test substance monohydrate at 0, 1, 3.2, 10, 32, 100, 320, 1000 and 3200 mg/L for 24 h and development to the D-stage veligers was observed. No analytical dose verification was conducted. Under the study conditions the nominal 24 h EC50 of the test substance to Pacific oyster was determined to be 1200 mg/L (Whale, 1995).

A study was conducted to determine the acute toxicity of the test substance to brown shrimp (Crangon crangon) according to methods similar to MAFF and OECD guidelines, in compliance with GLP. Shrimp were exposed to the test substance to test concentrations of 62.5, 125, 250, 500 and 1000 mg/L under semi-static conditions (replacement at 48 and 96 h). The test substance was readily soluble in the dilution and the resulting test dilutions were noted as clear and colourless. Test concentrations were analysed by ICP-MS and were all found to be greater than 80% of nominal. No mortality was observed in the control tank at the end of the test period. This is within the range of mortality acceptable for validation of the test results. Under the study conditions, the 96h LC50 of the test substance to brown shrimp was determined to be equivalent to 875 mg/L and the 96h NOEC 500 mg/L (measured) (Mallett 2011).

A range-finding study was conducted to determine the acute toxicity of the test substance to mysid shrimp (Mysidopsis bahia). The procedure was based on US Federal Register guidelines. Mysid shrimp were exposed to the test substance at 0, 30,000, 60,000, 125,000, 500,000 and 1,000,000 ppm (mg/L) for 96 h. Mortality and moulting incidence were determined at 3, 6, 24, 48, 72 and 96 h. No analytical dose verification was conducted. Mortality occurred at all doses, including controls, with 100% mortality at 320 mg/L. Moulting was also observed at 0, 56 and 180 mg/L. Under the study conditions, the nominal 96 h LC50 of the test substance was lower than the lowest tested dose of 30,000 mg/L (Ceron, 1997).

A study was conducted to determine the acute toxicity of the test substance to Mysid shrimp (Mysidopsis bahia) according to USEPA guidance - Short Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms. Following a range-finding study, Mysid shrimp were exposed to the test substance at concentrations of 91, 151, 420 and 700 mg/L under semi-static conditions (replacement on Days 1 -6). No analytical dose verification. No mortality was observed in the control tank at the end of the test period. Under the study conditions, survival and growth rate for the test substance were recorded as follows: for the survival endpoint (nominal), the IC25 was 360 mg/L, the IC50 was 481 mg/L and the 48 h LC50 was 521 mg/L. For the growth endpoint (nominal), the IC25 was 260 mg/L and the IC50 was 392 mg/L (Daniel, 2011).