thiacloprid (ISO);(Z)-3-(6-chloro-3-pyridylmethyl)-1,3-thiazolidin-2-ylidenecyanamide;{(2Z)-3-[(6-chloropyridin-3-yl)methyl]-1,3-thiazolidin-2-ylidene}cyanamide

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

Study period:

15 - 19 May 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

1992

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 (control), 6.48, 10.8, 18.0, 30.0 and 50 mg/L
- Sampling method: Water samples were taken from the center of the aquaria at test start and end.
- Sample storage conditions before analysis:

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Several volumes of a stock solution (5.00 g test substance and 50 ml dimethylformamide (DMF)) were diluted into the respective aquaria.
- Controls: control: dilution water only, solvent control: 500 µL DMF/L
- Chemical name of vehiclle: dimethylformamide
- Concentration of vehicle in test medium: stock solution: 100%, final test solutions: 64.75 - 500 µL/L, control: 0%, solvent control: 500µL/L
- Test concentration separation factor: 1.667

Test organisms (species):

Lepomis macrochirus

Details on test organisms:

TEST ORGANISM
- Common name: bluegill
- Lot: F3 / 95
- Source: obtained from Osage Catfisheries, Osage Beach, USA on 14 February 1995
- Length at study initiation: 3.1 + 0.3 cm (Mean + SD)
- Weight at study initiation: 0.7 + 0.2 g (Mean + SD)

ACCLIMATION
- Acclimation period: 14 days
- Acclimation conditions: same as test
- Type and amount of food during acclimation: Brutfutter FB50, Kronen Fischkraftfutter,
- Feeding frequency during acclimation: Fish were not fed 48 h before and during the study.
- Health during acclimation: less than 3% mortality
- Prophylactic treatment directly after arriving of the fish with Oxytetracyclin-Hydrochlorid (4 g/100 L water, 2*24h), beginning on February 14 and finishing on February 16, 1995

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

40 - 60 mg CaCo3/L

Test temperature:

22.2 - 23.0 °C

pH:

7.0 - 7.2

Dissolved oxygen:

100 - 105 %

Nominal and measured concentrations:

Nominal concentrations: 0 (control), 0 (solvent control), 6.48, 10.8, 18.0, 30.0 and 50 mg/L
Mean measured concentrations: < LOQ (control), < LOQ (solvent control), 6.20, 10.6, 16.7, 28.4 and 48.7 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: aquaria
- Material, size, headspace, fill volume: glass, 32 x 36 x 38 cm ( l x d x h), 3.7 L, 40 L
- Aeration: no
- No. of organisms per vessel: 20
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): 1
- Biomass loading rate: 0.35 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted water (Ca++: 0.384 mmole/L, Mg++: 0.096 mmole/L, Na+: 0.148 mmole/L, K+: 0.015 mmole/L, Cl-:0.783 mmole/L, HCO3-: 0.148 mmole/L, SO4-: 0.096 mmole/L)
- Culture medium different from test medium: no
- Intervals of water quality measurement: 0, 24, 48, 72 and 96 h after test start (dissolved oxygen, pH)

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16/8 h light/dark
- Light intensity: not reported

EFFECT PARAMETERS MEASURED: mortality and behavior (4, 24, 48, 72 and 96 h after test start)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.667

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

25.2 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence interval = 16.7 - 48.7 mg test substance/L

Details on results:

- Mortality of control: 0%

Reported statistics and error estimates:

The LC50-values with 95%-confidence intervals for every 24-hour period if possible were calculated by using a computer program which estimated the LC50 using three statistical techniques: moving average, binomial probability or probit analysis.

Sublethal observations / clinical signs:

Table 1: Analytical results

Nominal test concentration in mg test substance (mg pure a.s./L)	Measured concentrations in mg pure a.s./L			Mean measured concentration in mg test substance/L	Percent of nominal
	at day 0	at day 4	Mean
Control	< 0.05	< 0.05	-	-	-
Solvent control	< 0.05	< 0.05	-	-	-
6.48 (6.31)	6.15	5.93	6.04	6.20	96
10.8 (10.5)	10.4	10.3	10.4	10.6	99
18.0 (17.5)	16.4	16.0	16.2	16.7	93
30.0 (29.2)	27.5	27.7	27.6	28.4	95
50.0 (48.7)	46.9	47.9	47.4	48.7	97

Table 2: Summary of sublethal effects and mortality of thiacloprid to bluegill sunfish (L. macrochirus)

Mean measured concentrations in mg test substance/L (mg pure a.s./L)	4h		24h		48h		72h		96h
	Dead	Obs.	Dead	Obs.	Dead	Obs.	Dead	Obs.	Dead	Obs.
Control	0	-	0	-	0	-	0	-	0	-
Solvent control	0	-	0	-	0	-	0	-	0	-
6.20	0	-	0	DF	0	DF	0	DF	0	DF
10.6	0	DF	0	DF	0	DF, AP	0	DF, AP	0	DF, AP
16.7	0	DF, AP	0	DF, AP	0	DF, AP	0	DF, AP	0	DF, AP, V
28.4	0	DF, AP, OB, AT, V	2	DF, AP, OB, AT, SR, V	4	DF, AP, OB, AT, SR, V	12	DF, AP, BO, V	14	DF, AP, BO
48.7	0	DF, AP, OB, AT, V, TS	20	-	20	-	20	-	20	-

DF = Darkened coloration,

AP = quiescent – marked by a state of inactivity or abnormally low activity

OB = at water surface – rising and remaining unusually long at the surface

AT = labored respiration

V = vertical oriented – turned up or down in a vertical position and remaining in that position for an unusually long time

TS = loss of equilibrium-turned laterally, more or less, from the normal body orientation.

Table 1: Validity criteria for OECD 203 (2019)

Criterion from the guideline	Outcome	Validity criterion fulfilled
The mortality in the control(s) should not exceed 10% (or one fish if less than ten are used) at the end of the test	0%	yes
The dissolved oxygen concentration must have been at least 60 per cent of the air saturation value throughout the test	100 - 105%	yes
There must be evidence that the concentration of the substance being tested has been satisfactorily maintained, and preferably it should be at least 80% of the nominal concentration throughout the test. If the deviation from the nominal concentration is greater than 20 per cent, results should be based on the measured concentration.	Mean measured concentrations range from 93 to 97% of nominal concentrations. Effect values refer to measured concentrations.	yes

Validity criteria fulfilled:

yes

Remarks:

For further, details, please refer to 'Any other information on results incl. tables'.

Conclusions:

The LC50 (96 h) for bluegill sunfish (Lepomis macrochirus) was determined to be 25.2 mg test substance/L (mean measured) under static conditions.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 - 22 Aug 1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: FIFRA 72-3

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 (control), 0 (solvent control), 1.88, 3.75, 7.5, 15 and 30 mg a.i./L
- Sampling method: 10 mL samples were collected from the aquaria at mid-depth using a glass pipet on day 0 and 4.
- Sample storage conditions before analysis: Test solution samples were analyzed on the same day as collection.

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A primary stock solution was prepared by dissolving 30.6123 g of test substance into 250 mL of dimethylformamide (DMF). A secondary stock solution was prepared by dissolving 12.5 mL (1.5 g a.i./L) of the primary stock solution into a total volume of 25 mL DMF (60 mg/mL). This stock solution was used to prepare the batches of different test solution.
- Differential loading: no
- Controls: control: dilution water only, solvent control: dilution water and 500 µL DMF/L
- Chemical name of vehicle: dimethylformamide (DMF)
- Concentration of vehicle in test medium: stock solution: 100%, final test solutions: 250 - 469 µL/L, control: 0%, solvent control: 500 µL/L
- Test concentration separation factor: 2

Test organisms (species):

Cyprinodon variegatus

Details on test organisms:

TEST ORGANISM
- Common name: sheepshead minnow
- Lot no: ABS080197
- Source: from Aquatic Biosystems, Fort Collins, USA (on 01 Aug 1997)
- Age at study initiation: approx. 75 days
- Length at study end: 15 - 24 mm (20.3 ± 2.2 mm)
- Weight at study initiation: 0.1 - 0.4 g ww (0.23 ± 0.07 g)

ACCLIMATION
- Acclimation period: 17 days
- Acclimation conditions: same as test (exception: temperature was between 23 and 31 °C for four days (12-9 days prior test start, fish did not exhibit any abnormal behavior or mortality as a result of this change in temperature)
- Type and amount of food during acclimation: newly hatched brine shrimp and/or a commercial fish food (Tetramin® or trout chow)
- Feeding frequency during acclimation: daily (no feeding 48 hours prior test)
- Health during acclimation: no

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

21.6 - 23.1 °C

pH:

7.2 - 7.8

Dissolved oxygen:

5.2 - 6.0 mg/L (66 - 76 %)

Salinity:

17 ‰

Nominal and measured concentrations:

Nominal concentrations: 0 (control), 0 (solvent control), 1.88, 3.75, 7.5, 15 and 30 mg a.i./L
Mean measured concentrations: < LOQ (control), < LOQ (solvent control), 1.89, 3.50, 7.55, 15.5 and 30.7 mg a.i./L

Details on test conditions:

TEST SYSTEM
- Test vessel: aquaria
- Material, size, headspace, fill volume: stainless steel, 32.4 x 24 x 26.5 cm (l x wx h), 3.6 L, 17 L
- Aeration: no
- No. of organisms per vessel: 20 (in 7.5 mg/L: 21)
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): 1
- Biomass loading rate: 0.27 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reverse osmosis (RO) water: Treated city water that been dechlorinated with sodium metabisulfite, passed through a multimedia filter and granular activated carbon units, passed through a 1 micron filter, and demineralized by conventional softeners, and treated by double pass reverse osmosis and finally sterilized by ultraviolet light.
- Chlorine: < 0.003 mg/L
- Alkalinity: 33 mg/L (as CaCO3)
- Culture medium different from test medium:
- Intervals of water quality measurement: dissolved oxygen, salinity and pH after 0, 48, 96 hours

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16:8 h / light:dark
- Light intensity: 820 lux

EFFECT PARAMETERS MEASURED: mortality and behavioral observations (after 24, 48, 72 and 96 hours)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Range finding study
- Test concentrations: 0.1 - 100 mg/L
- Results used to determine the conditions for the definitive study: Mortality and sublethal effects were observed at 10 mg/L and higher concentrations. No mortality or sublethal effects were noted at nominal concentrations below 10 mg/L.

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

19.7 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence interval = 15.5 - 30.7 mg a.i./L

Details on results:

- Other biological observations: 15% mortality at the 15.5 mg a.i./L test level and 100% mortality at the 30.7 mg a.i./L test level
- Mortality of control: 0%
- Effect concentrations exceeding solubility of substance in test medium: No undissolved test substance was observed in the test chambers.

Reported statistics and error estimates:

The 96-hour LC50 value and the 95 percent confidence limits were calculated by a LC50 computer program developed by Stephan et al. (1982) using the following statistical methods: binomial probability, moving average angle, and probit.

Sublethal observations / clinical signs:

Table 1: Cumulative mortality and behavioural observations of the sheepshead minnow exposed to thiacloprid

Mean measured concentration [mg/L]	24 h		48 h		72 h		96 h
	Dead	Observations	Dead	Observations	Dead	Observations	Dead	Observations
Control	0	20 N	0	20 N	0	20 N	0	20 N
Solvent control	0	20 N	0	20 N	0	20 N	0	20 N
1.89	0	20 N	0	20 N	0	20 N	0	20 N
3.50	0	20 N	0	20 N	0	20 N	0	20 N
7.55	0	21 Q	0	21 Q	0	16 Q; 5 N	0	19 Q; 2 N
15.5	2	18 Q	3	17 Q	3	14 Q; 3 N	3	15 Q; 2 N
30.7	20	-	20	-	20	-	20	-

Key to Observations: N = Normal; Q = Quiescent

Table 2: Measured concentrations during the 96-hour exposure test

Sampling	Measured test concentrations
Nominal concentration [mg/L]	Day 0 [mg/L]	Day 4 [mg/L]	Mean [mg/L]	Percent of nominal
Control	< 0.2	< 0.2	--	-
Solvent control	< 0.2	< 0.2	-	-
1.88	1.85	1.93	1.89	101
3.75	3.44	3.56	3.50	93
7.5	7.46	7.6	7.55	101
15	15.2	15.8	15.5	103
30	30.7	^a	30.7	102

^aAll fish at 30 mg/L were dead prior to day 4, therefore no analysis was needed.

Table 1: Validity criteria for OECD 203 (2019)

Criterion from the guideline	Outcome	Validity criterion fulfilled
The mortality in the control(s) should not exceed 10% (or one fish if less than ten are used) at the end of the test	0%	yes
The dissolved oxygen concentration must have been at least 60 per cent of the air saturation value throughout the test	66 - 76%	yes
There must be evidence that the concentration of the substance being tested has been satisfactorily maintained, and preferably it should be at least 80% of the nominal concentration throughout the test. If the deviation from the nominal concentration is greater than 20 per cent, results should be based on the measured concentration.	93 - 103%	yes

Validity criteria fulfilled:

yes

Remarks:

For further, details, please refer to 'Any other information on results incl. tables'.

Conclusions:

The LC50 (96 h) for sheepshead minnow (Cyprinodon variegatus) was determined to be 19.7 mg a.i./L (mean measured) under static conditions.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

20 - 24 Feb 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

1992

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 (control), 0 (solvent control), 5.18, 8.64, 14.4, 24.0 and 40.0 mg/L
- Sampling method: samples were taken from the center of the aquaria at the beginning and end of the test

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A primary stock solution was prepared by dissolving 4.04 g of test substance into 50 L of dimethylformamide (DMF). This stock solution was used to prepare the batches of different test solution.
- Differential loading: no
- Controls: control: dilution water only, solvent control: dilution water and 500 µL DMF/L
- Chemical name of vehicle: dimethylformamide (DMF)
- Concentration of vehicle in test medium: stock solution: 100 %, final test solutions: 65 - 500 µL/L, control: 0 %, solvent control: 500 µL/L
- Test concentration separation factor: 1.667

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout
- Lot no.: F7 / 94
- Source: Dr. Rosengarten, Oesede-Georgsmarienhutte, Germany (obtained as as green eggs and milt at 13 Oct 1994)
- Length at study initiation: 4.4 + 0.3 cm (mean + SD)
- Weight at study initiation: 1.2 + 0.3 g (mean + SD)
- Holding conditions: held in culture tanks on a 16/8 hour light/dark photoperiod according to Braun et al., commercial trout diet (Brutfutter FB50, Kronen Fischkraftfutter)

ACCLIMATION
- Acclimation period: 48 h
- Acclimation conditions: same as test
- Health during acclimation: < 3 % mortality

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

40 - 60 mg CaCO3/L

Test temperature:

10.3 - 10.8 °C

pH:

7.0 - 7.4

Dissolved oxygen:

98 - 99%

Nominal and measured concentrations:

Nominal concentrations: 0 (control), 0 (solvent control), 5.18, 8.64, 14.4, 24.0 and 40.0 mg/L
Mean measured concentration: < LOD, < LOD, 4.99, 8.16, 13.3, 22.0 and 37.5 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: aquaria
- Material, size, headspace, fill volume: glass, 32 x 36 x 38 cm ( l x d x h), 3.7 L, 40 L
- Aeration: no
- No. of organisms per vessel: 20
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): 1
- Biomass loading rate: 0.6 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted water by adding salt stock solutions to demineralized water (Ca++: 0.384 mmole/L, Mg++: 0.096 mmole/L, Na+: 0.148 mmole/L, K+: 0.015 mmole/L, Cl-:0.783 mmole/L, HCO3-: 0.148 mmole/L, SO4-: 0.096 mmole/L)
- Culture medium different from test medium: no
- Intervals of water quality measurement: 0, 24, 48, 72 and 96 h after test start (dissolved oxygen, pH)

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16/8 h light/dark
- Light intensity: not reported

EFFECT PARAMETERS MEASURED: mortality and behavior (4, 24, 48, 72 and 96 h after test start)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.667

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

30.5 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence interval: 27.0 - 34.1 mg test substance/L

Details on results:

- Mortality of control: 0 %

Validity criteria fulfilled:

yes

Conclusions:

The LC50 (96 h) for rainbow trout (Oncorhynchus mykiss) was determined to be 30.5 mg test substance/L (mean measured) under static conditions.

Description of key information

LC50 (96 h) = 25.2 mg/L (mean measured, OECD 203, Lepomis macrochirus)

LC50 (96 h) = 19.7 mg/L (mean measured, FIFRA Guideline 72-3, Cyprinodon variegatus)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

25.2 mg/L

Marine water fish

Marine water fish

Dose descriptor:

LC50

Effect concentration:

19.7 mg/L

Additional information

Three experimental GLP studies are available testing the acute toxicity of 3-(2-chlor-5-pyridyl-methyl)-cyanimino-1,3-thiazolidin towards fish. Two studies were performed with freshwater fish Lepomis macrochirus and Oncorhynchus mykiss. One study tested the effects of the test substance on marine sheepshead minnow Cyprinodon variegatus.

In the key freshwater study, bluegill (L. macrochirus) were exposed for 96 hours under static conditions to five concentrations of the test item ranging from 6.20 to 48.7 mg/L (mean measured) as well as a solvent control (500 µL dimethylformamide (DMF)/L and a (water) control according to OECD 203. Mean measured test concentrations (analysed at the start and end of the exposure period) ranged from approximately 93 % - 99 % of nominal concentrations. The results of the study were based on mean measured concentrations. The LC50 (96 h) value was determined to be 25.2 mg/L, with a 95 % confidence interval of 16.7 to 48.7 mg/L.

A further freshwater study performed with the rainbow trout (O. mykiss) was determined in a static 96-hour test. In this test, five groups of fish were exposed to nominal concentrations between 5.18 and 40 mg/L. An additional group of fish was exposed to the highest used solvent concentration (500 µl DMF/L test water). A further control group of fish was exposed to untreated test water. Mean measured test concentrations of the test substance during the whole test period ranged from 93 - 96 % of nominal concentrations.

The marine key study sheepshead minnow (C. variegatus) was conducted according to EPA FIFRA 72-3. Fish were exposed to the test item nominal concentrations ranging from 1.88 to 30.0 mg/L. The mean measured concentrations during the test period ranged from 93 - 103 % of the nominal concentrations. The LC50 (96 h) was determined to be 19.7 mg a.i./L (mean measured). The LC50 (96 h) was determined to be 30.5 mg test substance/L (expressed as mean measured concentration).