rac-(1R,4S,4aR,8R,8aS)-9-(dichloromethylidene)-8-hydroxyoctahydro-1,4-methanonaphthalen-5(1H)-one

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13 Apr 2015 to 17 Apr 2015

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: MEP, P.R. China, the Guideline for the Testing of Chemicals, Effects on Biotic Systems (the Second Edition), No. 203 "Fish Acute Toxicity Test''

Version / remarks:

2013

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

During the test, three samples were collected from each test vessel and one from the control group in the freshly prepared media at 0 and 48 hours and in the expired media at 48 and 96 hours.

Vehicle:

yes

Remarks:

Acetone

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Appropriate weights of the test item (0.39642g, 0.53654g, 0.72410g, 0.97786g and 1.32147g for each test solution) were dissolved in 25 mL acetone to obtain test item solutions of 15.0, 20.3, 27.4, 37.0 and 50.0 mg/mL (taking into account the analytical purity of the test item). 10 mL of each acetone solution was applied into dry glass bottles and the bottles were rotated to allow the acetone to evaporate, thus leaving a thin coating of test item on the inner surface. Afterwards, 10 L of test water was added into the glass bottles and stirred magnetically for 1.5 hrs at 450 rpm to obtain the test solutions. The test was performed with renewal of the test solutions every 48 hours.
- Controls: Blank control and positive control
- Concentration of vehicle in test medium: Acetone was evaporated from the test vessel before introduction of test organisms.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebrafish
- Length at study initiation: 2.1 - 2.6 cm (sample of 5 random fish before test start)
- Weight at study initiation: 0.262 - 0.351 g (sample of 5 random fish before test start)

ACCLIMATION
- Acclimation period: At least 12 days
- Acclimation conditions: Water quality, light conditions and temperature were the same as the test conditions
- Type and amount of food during acclimation: Not reported
- Feeding frequency during acclimation: Twice on weekdays and once over the weekend until 24 hours before the start of the test
- Health during acclimation (any mortality observed): No signs of disease or mortalities during the initial 12 day acclimation period

FEEDING DURING TEST: None

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None reported

Hardness:

136 mg CaCO3/L

Test temperature:

21.85 - 24.30 °C

pH:

7.11 - 8.18

Dissolved oxygen:

69.7 - 98.3 % ASV (air saturation value)

Salinity:

Not applicable

Conductivity:

Not reported

Nominal and measured concentrations:

- Nominal concentrations: 15, 20.3, 27.4, 37.0 and 50 mg/L
- Mean measured concentrations: 14.39, 19.42, 24.69, 30.96 and 38.01 mg/L (corresponding to 95.9, 95.7, 90.1, 83.7 and 76.0 % of the nominal concentrations).

Details on test conditions:

TEST SYSTEM
- Test vessel: Tanks (30 x 30 x 20 cm)
- Material, size, headspace, fill volume: Glass tanks filled with 10 L test solution
- Aeration: The water was aerated for more than 24 hours to attain dissolved oxygen saturation before use
- Renewal rate of test solution: Every 48 hours
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: < 1.0 g fish/L water

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Groundwater treated with Aquapro Pure Water System
- Total organic carbon: < 2 mg/L
- Metals: < 0.001 mg/L As, < 0.001 mg/L Cd, < 0.004 mg/L Cr(6+), < 0.005 mg/L Pb, < 0.0001 mg/L Hg, < 0.001 mg/L Se, < 0.03 mg/L Al, < 0.05 mg/L Fe, < 0.05 Mn, < 0.0075 Cu, < 0.05 mg/L Zn
- Intervals of water quality measurement: Dissolved oxygen and pH were measured daily and temperature was recorded in 1 hr intervals

OTHER TEST CONDITIONS
- Adjustment of pH: None reported
- Photoperiod: 12 hours light: 12 hours darkness
- Light intensity: Not reported

EFFECT PARAMETERS MEASURED: Mortality and toxic signs (e.g. loss of equilibrium, swimming behaviour, respiratory function, pigmentation, etc.) were recorded at 3, 24, 48, 72 and 96 hours after exposure. The criteria for mortality were no visible movement (e.g. gill movement) and no reaction to touching of the caudal peduncle.

TEST CONCENTRATIONS
- Range finding study: In a non-GLP range-finding test using the concentrations of 5, 10, 20 and 50 mg/L, the test fish at 20 mg/L showed toxic symptoms such as erratic swimming, lethargy, discoloration. The test fish at 50 mg/L showed 100% mortality. It was assumed that the LC50 may be in the range of 20 - 50 mg/L.
- Test concentrations: 5, 10, 20 and 50 mg/L
- Results used to determine the conditions for the definitive study: At 20 mg/L, fish showed toxic symptoms such as erratic swimming, lethargy and discoloration. At 50 mg/L, 100 % mortality was observed.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

25.87 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95 % CL: 23.89 - 28.01 mg/L

Details on results:

- Behavioural abnormalities: at test concentrations of 19.42 mg/L and above, visible toxic signs were observed, such as erratic swimming, lethargy and discolouration.
- Mortality of control: No deaths occurred in the control group during the 96-hour exposure period.
- Other adverse effects control: No visible toxic signs were observed in the control group during the 96-hour exposure period.

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- LC50: 277.0 mg/L (24 hours)

Reported statistics and error estimates:

The 96-hour LC50 and the 95 % confidence limits were derived by Trimmed Spearman-Karber method using mean measured concentrations.

Sublethal observations / clinical signs:

Cumulative mortality and toxic signs of Danio rerio exposed to the test item

Nominal concentration (mg/L)	Mean measured concentration (mg/L)	Initial number of exposed fish	Cumulative mortality
			3 h	24 h	48 h	72 h	96 h
Control	-	7	0	0	0	0	0
15	14.39	7	0	0	0	0	0
20.3	19.42	7	0 (7sd)	0 (7sld)	0 (7sld)	0 (7sld)	0 (7sld)
27.4	24.69	7	0 (7sd)	1 (6sld)	2 (5sld)	2 (5sld)	2 (sld)
37.0	30.96	7	0 (7sld)	7	-	-	-
50	38.01	7	2 (5sld)	7	-	-	-

The number of fish with toxic signs are given in parentheses:

s: erratic swimming

l: lethargy

d: discolouration

Validity criteria fulfilled:

yes

Remarks:

see "any other information on materials and methods incl. tables".

Conclusions:

The 96-hour LC50 for Danio rerio exposed to the test item was determined to be 25.87 mg/L (95 % confidence limits: 23.89 - 28.01 mg/L).

Executive summary:

A 96-hour acute toxicity study of the test item was conducted with zebra fish (Danio rerio) in a semi-static system according to OECD Guideline Number 203 (1992). Fish were exposed to nominal test item concentrations of 15, 20.3, 27.4, 37.0 and 50 mg/L (corresponding to mean measured test item concentrations of 14.39, 19.42, 24.69, 30.96 and 38.01 mg/L), alongside a blank control. Test solutions were renewed at 48 hours. The 96-hour LC50 was determined to be 25.87 mg/L (95 % confidence limits: 23.89 - 28.01 mg/L). No death or visible signs of toxicity were observed in the control group or treatment groups up to 14.39 mg/L. At 19.42 mg/L and above, visible toxic signs were observed, such as erratic swimming, lethargy and discolouration.

Description of key information

96-h LC50 = 25.87 mg/L, in freshwater zebrafish (Danio rerio), OECD 203, Xue 2015.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

25.87 mg/L

Additional information

A 96-hour acute toxicity study of the test item was conducted with zebra fish (Danio rerio) in a semi-static system according to OECD Guideline Number 203 (1992). Fish were exposed to nominal test item concentrations of 15, 20.3, 27.4, 37.0 and 50 mg/L (corresponding to mean measured test item concentrations of 14.39, 19.42, 24.69, 30.96 and 38.01 mg/L), alongside a blank control. Test solutions were renewed at 48 hours. The 96-hour LC50 was determined to be 25.87 mg/L (95 % confidence limits: 23.89 - 28.01 mg/L). No death or visible signs of toxicity were observed in the control group or treatment groups up to 14.39 mg/L. At 19.42 mg/L and above, visible toxic signs were observed, such as erratic swimming, lethargy and discolouration.