Benzamide, N-[[4-[(cyclopropylamino)carbonyl]phenyl]sulfonyl]-2-methoxy-

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:

04 Jun - 08 Jun 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1035 (Mysid Acute Toxicity Test)

Version / remarks:

adopted 1996

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A primary stock solution (also serving as the highest test concentration) was prepared by direct addition of the test substance to dilution water and sonication for approx. 20 min, followed by overnight mixing with a magnetic stirrer. The resulting solution had no visible sign of undissolved test substance.

Test organisms (species):

Americamysis bahia (previous name: Mysidopsis bahia)

Details on test organisms:

TEST ORGANISM
- Common name: Mysid shrimp
- Source: Laboratory cultures at Springborn Smithers; original source: Aquatic BioSystems Inc., Fort Collins Co, USA
- Age at study initiation (mean and range, SD): < 24 h
- Feeding during test: yes
- Food type: live brine shrimp nauplii (Artemia salina)
- Frequency: once daily

CULTURE CONDITIONS
- Mysids were cultured in one of several 76-L glass aquaria with a closed-loop recirculating filtration system providing artificial filtered seawater to the aquaria. The seawater in the aquaria was characterized as having a salinity range of 20 to 24‰ for the 14-day period prior to initiation of the definitive exposure. The area in which the mysids were cultured received a regulated photoperiod of 16 hours of light/8 hours of darkness. The culture solution temperature was maintained at 25 ± 2 °C. Juvenile mysids, < 24 hours old, were collected using a variation of the method described by Reitsema and Neff (1980).
- Type and amount of food: live brine shrimp (Artemia salina) nauplii
- Feeding frequency: once daily
- Food analysis: Levels of pesticides, PCBs and toxic metals were below levels of concern

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

no data

Test temperature:

23 - 24 °C

pH:

7.4 - 7.9

Dissolved oxygen:

4.6 - 7.2 mg/L
61 - 94% saturation

Salinity:

20‰ throughout the exposure

Nominal and measured concentrations:

Nominal: Control, 6.3, 13, 25, 50, 100 mg a.i./L
Mean measured (day 0 and day 4):

Details on test conditions:

TEST SYSTEM
- Test vessel: beakers
- Material, size, headspace, fill volume: material: glass, size: 1 L, fill volume: 0.9 L
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: The dilution water used during this study was prepared by filtering natural seawater collected from the Cape Cod Canal, Bourne MA, USA. The seawater was transferred with a pump (fiberglass reinforced thermoplastic housing) and a polyvinyl chloride (PVC) pipe and was then transported to the laboratory in a 3400-L fiberglass tank. In the laboratory, the seawater was passed through a series of polypropylene core filters (20- and 5-micron) and then recirculated within an epoxy-lined concrete reservoir prior to use. The seawater was pumped to the laboratory under constant pressure through PVC pipe and a polypropylene heat exchanger system. The seawater was diluted with laboratory well water to provide a salinity of 20 ± 3‰. The salinity was measured to be 20‰ and the pH was measured to be 7.9.
- Preparation of test substance solution: A primary stock solution was prepared prior to test initiation by adding 0.6110 g of the test substance (0.6000 g as active ingredient) to approximately 1.0 L of dilution water and sonicating for approximately 20 minutes. The solution was then brought to a total volume of 6.0 L with dilution water and mixed overnight using a magnetic stir plate and Teflon-coated stir bar. After mixing, the resulting 100 mg a.i./L stock solution was observed to be clear and colorless with no visible sign of undissolved test substance.
- Intervals of water quality measurement: Temperature, salinity, pH and dissolved oxygen were measured daily in each vessel.

OTHER TEST CONDITIONS
- Photoperiod: 14 h light/10 h dark
- Light intensity: 75 - 81 footcandles (810 - 870 lux)

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): mortality and behaviour were observed at test start and after 24, 48 and 96 h

TEST CONCENTRATIONS
- Spacing factor for test concentrations: approx. 2.0
- Range finding study
- Test concentrations: 1.0, 10, 50, 100 mg a.i./L
- Age of mysids: ≤ 24 h and 5 days
- Results used to determine the conditions for the definitive study: Since no difference in sensitivity was observed between the two age classes, juvenile (< 24 hours old) mysids were used during the definitive exposure. Based on these results and consultation with the Study Sponsor, nominal concentrations of 6.3, 13, 25, 50 and 100 mg a.i./L were chosen for the definitive exposure.

Reference substance (positive control):

not specified

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Details on results:

- Mortality of control: 5% mortality after 72 h and 5% after 96 h
- Mortality in test vessels after 72 h: 5% mortality at both 6.4 and 26 mg a.i./L
- Mortality in test vessels after 96 h: 5% mortality at both 6.4 and 13 mg a.i./L and 10% mortality at 26 mg a.i./L
The mortality observed in control and test vessels was within the expected range of naturally occuring variability and was not considered substance-related.

Table 1: Concentrations of AE 0001789 measured in the exposure solutions during the 96-hour exposure of mysids (Americamysis bahia).

Nominal Concentration (mg a.i./L)	Measured Concentration (mg a.i./L)
	0 Hour	96 Hour	Mean*	Percent of nominal
Control	<0.32b	<0.35b	NAc	NA
6.3	6.2		6.4	101
13	13		13	102
25	25		26	103
50	NRd		52e	104
100	NR		100e	104
QC#1 5.00	5.07 (101)	5.06 (101)
QC#2 25.0	28.4 (114)	25.0 (99.8)
QC#3 100	101 (101)	101 (101)

*            Mean measured concentrations were calculated using the actual analytical (unrounded) results and not the rounded (two significant figures) values presented in this table.

b            Concentrations expressed as less than values were below the limit of quantitation (LOQ). The LOQ for each analysis is dependent upon the linear regression, the area of the low standards and the dilution factor of the controls. The limit of quantitation for this exposure was determined to be 0.00562 and 0.00607 mg a.i./L for 0 hour and 96 hours, respectively.

c             NA = Not Applicable.

d            NR = Not Reported, due to sample processing error.

e            The 96-hour measured concentration was used as the mean measured value for this treatment level due to the 0-hour sample processing error.

QC = Quality Control sample with percent of recovery presented in parentheses.

 

 

Table 2: Mean measured concentrations tested, corresponding cumulative mortality, and observations made during the 96-hour static toxicity test exposing mysids (Americamysis bahid) to AE 0001789 technical.

Mean Measured Conc. (mg a.i./L)	Cumulative Percent Mortality (Number of Dead Mysids)a
	24-Hour			48-Hour			72-Hour			96-Hour
	A	B	Mean	A	B	Mean	A	B	Mean	A	B	Mean
Control	0 (0)	0 (0)	0	0 (0)	0 (0)	0	0 (0)	10 (1)	5	0 (0)	10 (1)	5
6.4	0 (0)	0 (0)	0	0 (0)	0 (0)	0	10 (1)	0 (0)	5	10 (1)	0 (0)	5
13	0 (0)	0 (0)	0	0 (0)	0 (0)	0	0 (0)	0 (0)	0	10 (1)	0 (0)	5
26	0 (0)	0 (0)	0	0 (0)	0 (0)	0	0 (0)	10 (1)	5	0	20 (2)	10
52	0 (0)	0 (0)	0	0 (0)	0 (0)	0	0 (0)	0 (0)	0	0 (0)	0 (0)	0
100	0 (0)	0 (0)	0	0 (0)	0 (0)	0	0 (0)	0 (0)	0	0 (0)	0 (0)	0

a            The actual number of mortalities is presented in parentheses.

Table 3: Validity criteria for OECD 202 (2004)

Criterion from the guideline	Outcome	Validity criterion fulfilled
In the control, including the control containing the solubilising agent, not more than 10% of the daphnids should have been immobilized.	At the end of the test, 5% of the daphnids were immobilized in the controls.	yes
The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in control and test vessels.	The dissolved oxygen concentrations throughout the test were ≥ 4.6 mg/L in control and test vessels.	yes

 

Validity criteria fulfilled:

yes

Remarks:

See Table 3 in "Any other information on results incl. tables".

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

07 Aug - 11 Aug 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1025 (Bivalve Acute Toxicity (shell deposition test))

Version / remarks:

Draft, 1996

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

other aquatic mollusc: Crassostrea virginica

Test type:

flow-through

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

no data

Test temperature:

21 - 22 °C

pH:

7.6 - 8.1

Dissolved oxygen:

6.2 - 7.7 mg/L

Salinity:

19 - 21 ‰

Nominal and measured concentrations:

Nominal: Control, 1.0, 2.6, 6.4, 16, 40 and 100 mg a.i./L
Measured:

Reference substance (positive control):

not specified

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

> 94 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: shell growth

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

14 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: shell growth

Remarks on result:

other: based on Williams' Test

Details on results:

No mortality or sublethal effects were observed among oysters exposed to any of the treatment levels tested or the control.

Table 1: Effects of AE 0001789 technical on the shell deposition of Eastern oysters (Crassostrea virginica) after 96 h of exposure.

Mean Measured Concentration (mg a.i./L)	Mean Shell Deposition in mm (SD)	Mean Reduction (%)
Control	2.3 (1.0)	Not applicable
0.84	2.5 (1.1)	-9
1.8	2.4 (1.0)	-3
3.9	2.2 (1.0)	4
14	2.4 (1.2)	-4
42	1.3 (0.7)	43
94	1.2 (0.7)	49

Table 2: Concentrations of AE 0001789 measured in the exposure solutions during the 96-hour exposure of Eastern oysters (Crassostrea virginica).

Nominal Concentration (mg a.i./L)	Measured Concentration (mg a.i./L)
	0 Hour	96 Hour	Mean*	Percent of Nominal*
Control	<0.047b	<0.045b	NAc	NA
1.0	0.84	0.83	0.84	84
2.6	2.0	1.6	1.8	70
6.4	4.6	3.3	3.9	61
16	14	14	14	89
40	45	39	42	105
100	93	95	94	94
QCd#1 (0.500)	0.514 (103)e	0.526 (105)
QC#2 (16.0)	15.4 (96.5)	15.2 (94.8)
QC#3 (100)	99.1 (99.1)	103 (103)

*            Mean measured concentrations and percent of nominal were calculated using the actual analytical (unrounded) results and not the rounded (two significant figures) values presented in this table.

b            Concentrations expressed as less than values were below the limit of quantitation (LOQ). The LOQ for each analysis is dependent upon the linear regression, the area of the low standards and the dilution factor of the controls. The limit of quantitation for this exposure was determined to be 0.00465 and 0.0446 mg a.i./L for 0 hour and 96 hours, respectively.

c             NA = Not Applicable.

d            QC = Quality Control sample.

e            Percent recovery for each QC sample is presented in parentheses

 

 

Table 3: Individual growth (shell deposition, in mm) measurements of Eastern oysters (Crassostrea virginica) after 96 hours of exposure to AE 0001789 technical.

Replicate	Measured Conc. (mg a.i./L)
	Control		0.84		1.8		3.9		14		42		94
	A	B	A	B	A	B	A	B	A	B	A	B	A	B
1	1.9	1.6	1.3	2.7	2.6	1.9	4.6	1.6	1.7	2.1	1.5	1.8	0.9	1.6
2	1.6	1.9	2.1	4.7	2.3	2.0	2.8	1.4	2.3	0.8	1.1	1.6	0.3	2.0
3	2.9	1.6	1.9	3.2	1.7	4.1	1.9	2.3	3.6	4.2	1.3	0.6	1.6	1.5
4	4.4	1.7	1.0	5.0	3.9	2.5	4.4	2.6	2.0	1.5	2.0	1.4	0.7	0.8
5	2.0	2.2	3.6	2.9	2.5	1.8	1.4	1.9	2.1	2.9	1.4	1.1	1.8	1.2
6	0.6	1.8	2.3	4.6	2.9	1.3	1.7	2.6	2.7	3.0	1.1	1.0	0.9	1.1
7	4.3	2.3	1.9	1.7	2.9	2.1	1.8	3.2	1.1	2.3	0.9	1.5	0.9	1.4
8	2.1	2.5	2.8	2.0	1.8	2.1	4.0	4.2	4.9	2.8	0.6	1.8	0.8	2.0
9	2.0	1.8	2.6	2.6	2.1	1.4	2.1	3.6	1.8	1.1	1.1	0.4	0.0	1.1
10	1.9	2.0	4.1	3.6	4.5	2.2	1.9	2.6	1.3	2.7	1.0	1.4	0.4	0.4
11	3.2	1.1	1.0	0.9	1.2	0.9	1.6	2.5	1.9	4.0	1.4	2.2	0.7	3.6
12	1.7	1.7	1.8	1.7	1.9	3.8	0.7	1.9	0.8	3.2	0.8	2.5	1.0	0.5
13	2.1	2.3	2.2	2.9	4.2	3.4	2.0	3.0	1.5	1.5	0.3	0.6	1.2	2.9
14	1.7	4.6	2.1	1.6	2.1	4.0	1.3	1.2	0.9	5.4	1.1	0.7	0.0	1.6
15	1.8	2.7	2.0	5.1	2.9	0.4	1.3	1.4	3.3	4.3	1.7	0.6	1.2	0.0
16	2.3	2.6	1.6	1.8	2.0	4.3	4.0	2.5	1.6	2.5	1.8	1.2	1.4	1.4
17	1.8	4.1	2.3	3.3	3.2	1.6	1.7	1.3	0.7	2.7	1.9	1.3	1.4	1.7
18	2.9	2.7	3.5	1.2	2.3	2.0	0.7	1.8	2.7	4.7	1.3	0.2	0.8	0.7
19	2.3	2.1	2.0	2.3	2.3	1.1	1.2	2.9	2.5	1.1	0.4	3.2	1.1	0.7
20	1.1	4.8	1.8	3.7	0.8	2.3	2.0	1.6	2.3	2.3	2.1	2.9	2.3	1.9
Replicate Mean	2.2	2.4	2.2	2.9	2.5	2.3	2.2	2.3	2.1	2.8	1.2	1.4	0.97	1.4
Replicate (SD)a	0.9	1.0	0.8	1.3	0.9	1.1	1.2	0.8	1.0	1.3	0.5	0.8	0.6	0.8
Treatment Mean (SD)	2.3 (1.0)		2.5 (1.1)		2.4 (1.0)		2.2 (1.0)		2.4 (1.2)		1.3 (0.7)		1.2 (0.7)

a            SD = Standard Deviation

Validity criteria fulfilled:

not applicable

Reference 3

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 - 04 Mar 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1010 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

Qualifier:

according to guideline

Guideline:

other: EPA-FIFRA Guideline 72-2

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Sampling method: Water samples were collected from all test vessels and were analyzed at 0 hours (new solutions), and 48 hours (old solutions) to measure actual exposure concentrations.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A stock solution was made by filling an 8-L all glass aquarium with approximately 5 L of dilution water. The tank then received 0.7191 g of the test material and was mixed, using an electric stirrer, for approximately 30 minutes. The tank was then brought up to 7 L with dilution water and mixed overnight. After approximately 19 hours of mixing there were no precipitates visible and the mixing was stopped. The extended mixing period was necessary in order to solubilize the test material technical to the nominal limit dose concentration of 100 mg a.i./L. The 100 ppm test solution was prepared by bringing a 2-L volumetric flask to volume with the stock solution and inverting it several times.
- Controls: The control was prepared using dilution water only.

Test organisms (species):

Daphnia magna

Details on test organisms:

- Common name: Daphnia magna
- Strain/clone: Lot No. ABS 080603
- Age at study initiation: < 24 hours
- Method of culturing: The daphnids were cultured in hard blended water and fed a minimum of three times per week with algae (Pseudokirchneriella subcapitata and/or blended Tetrafin® flake food). The culture water was renewed three times per week. The culture area was maintained on a 16-hour light, 8-hour dark photoperiod, and a temperature range of 20 ± 2 °C.
- Method of breeding: Ten <24 hour old neonates were isolated to start a subculture on February 13, 2004. First instar daphnids (<24 hours old) were obtained for the test material study from the third brood (or later) of the second generation adult (18 days old) daphnids. The daphnids were held under culture conditions in glass beakers which were filled to a volume of 300 mL with dilution water. No ephippia and no immobilized Daphnia were observed in the subculture; all organisms appeared healthy and normal.
- Source: Obtained from an in-house culture maintained since August 2003. The primary culture was obtained from Aquatic Biosystems, Fort Collins, CO.
- Feeding during test: No

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

174 (172 - 176) mg/L as CaCO3

Test temperature:

19.6 - 20.6 °C

pH:

8.3 to 8.4

Dissolved oxygen:

8.5 to 9.0 mg/L, representing 93 to 99% saturation at 20 °C

Nominal and measured concentrations:

Nominal concentrations: Control, 100 mg/L
Measured concentrations: <0.61, 102 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: 250-mL glass beakers containing approximately 200 mL of test solution.
- Aeration: No
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- Biomass loading rate: The loading rate for each test vessel was approximately 1 daphnid per 40 mL of test solution.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: according to guideline
- Intervals of water quality measurement: Hardness, conductivity, alkalinity, pH and dissolved oxygen were measured in both test levels at 0 and 48 hours.

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 16-hours light and 8-hours dark
- Light intensity: 64.4 foot-candles (693 lux)

EFFECT PARAMETERS MEASURED: Daily observations were made for immobility and sublethal effects.

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 102 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 102 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mobility

Details on results:

- Mortality of control: One daphnid in the control and one in the 100 mg a.i./L test level were immobilized. Since the survival rate was greater than 90% and within what was considered to be background, no statistical procedures were necessary. The immobilized organism observed in the 100 mg a.i./L level was not considered to be dose related. The 48-hour EC50 was described as greater than the highest concentration tested.
- Any observations that might cause a difference between measured and nominal values: The mean measured concentration of the test material during the test period was 102 mg a.i./L for the nominal test level of 100 mg a.i./L.
- Effect concentrations exceeding solubility of substance in test medium: No undissolved test substance was observed in the test vessels. All measurements of the control treatment level were below the LOQ of 0.61 mg a.i./L.

Observations:

Cumulative immobilization of 5% (one organism per level) was observed in the control and 100 mg a.i./L test level. This number was within background immobilization occurrences in healthy cultures. No toxic effects were observed during the study.

Conclusion:

The 48-hour NOEC, LOEC and EC50 for Daphnia magna after exposure to AE 0001789 Technical were 102, >102, and >102 mg a.i./L, respectively.

Table 1: Measured Test Concentrations During the 48-hour Exposure of the Daphnia magna to AE 0001789 Technical

Nominal Concentration (mg a.i./L)	0 Hour (new)	48 Hour (old)	Mean± Standard Deviation*	Mean Percent of Nominal*
Control	ND	ND	---	---
100	103	101	102±1.4	102
Lab Spike (102 mg a.i./L)	106	103	105±2.1	105

ND = Not detected at or above the validated limit of quantitation (0.61 mg a.i./L).

*Calculations for mean, standard deviation, and percent of nominal concentration are based on recoveries from 0 and 48 hours.

 

 

Table 2: Cumulative Immobilizations and Behavioral Observations of the Daphnia magna Exposed to AE 0001789 Technical

Mean Measured Concentration (mg a.i./L)	0 Hour		24 Hour		48 Hour
	Immob.	Obs	Immob.	Obs	Immob.	Obs
Control	0	20 N	0	20 N	0	19 N
102	0	20 N	0	19 N	0	19 N

Immob. = Immobilized

Obs = Observations

N = Normal

 

 

Table 3: Validity criteria for OECD 202 (2004)

Criterion from the guideline	Outcome	Validity criterion fulfilled
In the control, including the control containing the solubilising agent, not more than 10% of the daphnids should have been immobilized.	At the end of the test, 5% of the daphnids were immobilized in the controls.	yes
The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in control and test vessels.	The dissolved oxygen concentration at the end of the test was ≥ 8.7 mg/L in control and test vessels.	yes

 

Validity criteria fulfilled:

yes

Remarks:

See Table 3 in "Any other information on results incl. tables".

Description of key information

EC50 (48 h): > 102 mg/L (arith. mean measured, Daphnia magna, OECD 202)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

> 102 mg/L

Additional information

Three GLP-studies on invertebrates are available; one test was conducted with a freshwater and two with a saltwater organism. All studies included analytical monitoring of the test concentrations by HPLC. The short toxicity term test on Daphnia magna was performed under static conditions according to OECD 202 (M-240262-02-1) in a limit test at a nominal concentration of 100 mg/L (measured: 102 mg/L). As no toxic effects were observed during the study the 48-hour EC50 was greater than 102 mg a.i./L test item (highest tested concentration).

The saltwater mysid, Americamysis bahia, was exposed to the test substance under static conditions for 96 hours and the EC50 was >100 mg a.i./L (arith. mean measured, M-277521-01-1).

The third test was conducted with a mollusk, the Eastern oyster (Crassostrea virginica) were exposed under flow-through conditions for 96 hours (M-278506-01-1). There were no mortalities or clinical signs of toxicity observed at any concentration tested. The EC50 value on shell growth was >94 mg a.i./L (arith. mean measured),

The test substance showed no acute effects to aquatic invertebrates.