5,9-dimethyldec-4-enal

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:

01-09-2017 to 09-03-2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study performed under GLP. All relevant validity criteria were met.

Justification for type of information:

Information as to the availability of the in vivo study is provided in 'attached justification'.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Qualifier:

according to guideline

Guideline:

other: Guidelines for the Testing of Chemicals, Effects on Biotic Systems, Version 2, 203 Fish Acute Toxicity Test, China Environmental Press, China (2013)

Deviations:

no

Principles of method if other than guideline:

The test was generally conducted in accordance with or equivalent to the following: China HJ/T153 - 2004 Chemical Test Guideline stipulations and Chemical Registration Center of MEP. The Guidelines for the Testing of Chemicals, effects on Biotic Systems, 203 Fish Acute toxicity test [M]. Second Edition. Beijing: China Environmental Press. 2013: 30-36. The test was also completed under OECD TG 203: Fish Acute Toxicity Test (1992).

GLP compliance:

yes (incl. QA statement)

Remarks:

inspected: April 2016; signature: May 2016

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Nominal: 0 (control), 0.8, 1.1, 1.5, 2.2 and 3.0 mg/L (geometric series factor 1.4); equivalent geometric mean measured concentrations: 0 (control), 0.342, 0.926, 1.447, 2.155 and 3.094 mg/L.
- Sampling method: 50 mL extract from test solution; of which 20 mL were used for subsequent analysis.
- Sample storage conditions before analysis: Actual concentrations of test substance in solution were immediately measured where possible. Residual sample volume was stored in a refrigerator (2-8°C) until conclusion of the study.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Stock preparation: Defined weighed amounts of test item were placed on to ca. 11 L of test water surface to give defined nominal concentration solutions. The solution was mixed by magnetic stirrer at 420-450 rpm for 2 hours and with 2 hours standing prior to exposure.
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Not applicable.
- Concentration of vehicle in test medium (stock solution and final test solution(s) or suspension(s) including control(s)): Nominal: 0 (control), 0.8, 1.1, 1.5, 2.2 and 3.0 mg/L (geometric series factor 1.4); equivalent geometric mean measured concentrations: 0 (control), 0.342, 0.926, 1.447, 2.155 and 3.094 mg/L.
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): None reported.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra fish (Brachydanio rerio)
- Strain: Not reported. Batch number 20170424
- Source: Recognised supplier (recorded in full study report) located in China.
- Age at study initiation (mean and range, SD): Not reported.
- Length at study initiation (length definition, mean, range and SD): Not reported. Prior to testing body lengths and weights of 5 fish from the acclimatized fish was randomly determined. The length and weight were in the range of 2.0-2.3 cm and 0.263-0.296 g, respectively (i.e. < 1.0g fish/litre).
- Method of breeding: Not reported.
- Feeding during test
- Food type: Feeding was conducted during acclimation (twice daily weekday ; once daily weekend) until 24-hours prior to test initiation.
- Amount: No feeding during exposure. Not applicable.
- Frequency: No feeding during exposure. Not applicable.

ACCLIMATION
- Acclimation period: > 7 days
- Acclimation conditions (same as test or not): Yes. Same water quality, temperature 23 ± 2°C and photoperiod as used during the test (12 hours light; 12 hours dark). Slight deviation: Oxygen concentration was in the range of > 80%ASV.
- Type and amount of food: Not reported.
- Feeding frequency: Feeding was conducted during acclimation (twice daily weekday ; once daily weekend) until 24-hours prior to test initiation.
- Health during acclimation (any mortality observed): None reported.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

Organisms were checked for abnormalities immediately following the end of the exposure period.

Hardness:

10 - 250 mg/L expressed as CaCO3

Test temperature:

Temperature 21.40-23.30 °C during test period, the test was performed in a temperature controlled environment with continuous monitoring and was maintained at 23 ± 2°C.

pH:

Test water (dechlorinated water): pH 7.0±0.5. The pH was in the range of 7.06-7.29 during the study.

Dissolved oxygen:

The test solutions were not aerated during the exposure. The dissolved oxygen concentration in the test solutions during the test was kept at not less than 60 % of the air saturation value. Measured range: 89.3-97.7%.

Nominal and measured concentrations:

- Preliminary range-finding test performed on semi-static test system with renewal every 24 hour intervals:
Semi-static exposure method was performed in the range-finding test with renewal of test solution every 24 hours. The range-finding test showed that there was no mortality observed at the nominal concentration of 1 mg/L and 100% mortality was observed at the nominal concentration of 3, 5 and 10 mg/L within the test period of 96 hours.
- Definitive test performed on semi-static test system with renewal every 24 hour intervals:
Nominal concentrations: 0 (control), 0.8, 1.1, 1.5, 2.2 and 3.0 mg/L (geometric series with a factor of 1.4); equivalent geometric mean measured concentrations: 0 (control), 0.342, 0.926, 1.447, 2.155 and 3.094 mg/L.
During the test, the dissolved test item concentration were analytically determined in the freshly prepared solution/medium (t=0h, 72 h) and in the aged medium/solution before renewal (t=24h*, 96h*).

Details on test conditions:

TEST SYSTEM
- Test vessel: 11 L wide-mouth packers with stopper
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: glass. ca. 11 Litre fill volume to reduce headspace to minimum
- Aeration: Not reported.
- Type of flow-through (e.g. peristaltic or proportional diluter): Not applicable.
- Renewal rate of test solution (frequency/flow rate): Renewal every 24 hours.
- No. of organisms per vessel: Seven (7) per vessel
- No. of vessels per concentration (replicates): One (1)
- No. of vessels per control (replicates): One (1)
- No. of vessels per vehicle control (replicates): Not applicable.
- Biomass loading rate: < 1.0 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Water used in the test were purified by the reverse osmosis equipment. (Certified annually).
- Conductivity: Not reported.
- Culture medium different from test medium: No.
- Intervals of water quality measurement: Every 24 hour intervals; before and after renewal

OTHER TEST CONDITIONS
- Adjustment of pH: None.
- Photoperiod: 12 hours photoperiod daily
- Light intensity: Not reported.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Mortalities and abnormalities; measured at 2h, 4h, 24h, 48h, 72h and 96h as applicable.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.4
- Justification for using less concentrations than requested by guideline: Not applicable. Five concentrations used.
- Range finding study
- Test concentrations: 0 (control), 1, 3, 5 and 10 mg/L nominal; no mortality at < 1 mg/L was reported and complete mortality at > 3 mg/L.
- Results used to determine the conditions for the definitive study: Yes.

Reference substance (positive control):

yes

Remarks:

Potassium Dichromate

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

2.58 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: C.I. - mg/L

Details on results:

- Behavioural abnormalities: There were no abnormal responses of test fish in the blank control. Observed abnormal responses are reported in table 3.
- Observations on body length and weight: Not reported.
- Mortality of control: None.
- Other adverse effects control: Yes. None reported.
- Abnormal responses: Observed abnormal responses are reported in table 3.
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: Not applicable.
- Effect concentrations exceeding solubility of substance in test medium: Not applicable.

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- 24h LC50: 232.78 (C.I. 195.14 - 277.68) mg/L

Reported statistics and error estimates:

Trimmed Spearman-Karber (TSK) method (EPA, Version 1.5) was used to derive the 96h-LCso value and the 95% confidence limit. And the LC50 was calculated with measured concentrations.

Sublethal observations / clinical signs:

Table 1. Median Lethal Concentration (LC50) and 95% confidence limits

Recommended observation times	LC50 (mg/L)	95% confidence limits (mg/L)
96 h	2.58	-

#1: LC50 based on geometric mean measured concentrations

 

Table 2. Cumulative mortality

Cumulative mortality
Group #1	Exposure duration (hours)
	2	4	24	48	72	96
Control	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
0.80 mg/L	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
1.1 mg/L	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
1.5 mg/L	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
2.2 mg/L	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
3.0 mg/L	0.0%	0.0%	71.4%	100%	-	-

#1: Group is control or nominal concentration group.

 

Table 3. Observed abnormal responses

Visible abnormalities
Group	Exposure duration (hours)
	2	4	24	48	72	96
Control	A (7/7)	A (7/7)	A (7/7)	A (7/7)	A (7/7)	A (7/7)
Treated 1	A (7/7)	A (7/7)	A (7/7)	A (7/7)	A (7/7)	A (7/7)
Treated 2	A (7/7)	A (7/7)	A (7/7)	A (7/7)	A (7/7)	A (7/7)
Treated 3	A (7/7)	A (7/7)	A (7/7)	A (7/7)	A (7/7)	A (7/7)
Treated 4	A (7/7)	A (7/7)	A (4/7) L (3/7)	A (4/7) L (3/7)	A (4/7) L (3/7)	A (4/7) L (3/7)
Treated 5	A (7/7)	A (7/7) L (2/7)	M (5/7) L (2/7)	M (7/7)	-	-

Note: A: means no abnormality reported ; L: means lethargy; M: means mortality

Validity criteria fulfilled:

yes

Conclusions:

The 96 hour LC50 for the test item to Danio rerio was determined to be 2.58 (C.I. -) mg/L based on geometric mean measured concentrations.

Executive summary:

The acute toxicity of the test item to Zebra fish (Danio rerio) was determined in a 96 hour semi-static test according to OECD TG 203 and the China Guidelines for the Testing of Chemicals, Effects on Biotic Systems, Version 2, 203 Fish Acute Toxicity Test (2013) under GLP. Based on the results of range finding tests the nominal concentrations of 0 (control), 0.8, 1.1, 1.5, 2.2 and 3.0 mg/L (geometric series with a factor of 1.4) were selected for exposure to fish groups (n=7 per group). One control containing no test item was also performed. The test item was renewed at 24 hour intervals within a 96 hour semi-static test system in response to ensuring adequate stability of exposure to test item. Observations were made at 2, 4, 24, 48, 72 and 96 hours after the start of the exposure.During the 96-hour exposure period, there was no mortality and visible toxic signs observed in the vessels of 0 (control), 0.8, 1.1 and 1.5 mg/L groups. There was lethargy observed in the 2.2 mg/L group, but no mortality. There were lethargies observed at 3.0 mg/L, and complete mortality before the end of the test period. Analytical measurements of test item concentration were made every 24 hours, pre- and post- medium renewal and the end of the exposure by GC-FID analysis.The results showed that for the nominal concentrations of 0.80, 1.1, 1.5, 2.2 and 3.0 mg/L gave overall geometric measured concentrations that were 0.342, 0.926, 1.447, 2.155 and 3.094 mg/L, which were 42.8, 84.2, 96.5, 98.0 and 103% of nominal concentrations, respectively. Therefore, effect concentrations were based on geometric mean measured concentrations that are analytically confirmed. Trimmed Spearman-Karber method analysis was used for LC50 value estimation and 95% confidence intervals determinations, as applicable. During the definitive test the water temperature was in the 21.40-23.30 °C, pH was 7.06-7.29 and air saturation was 89.3-97.7% indicating that environmental conditions were adequately maintained. Behavioural abnormalities and biological effects were reported during the course of the study. No abnormalities were observed in the control group. The 96h median LC50 was 2.58 (C.I. -) mg/L based on geometric mean measured concentrations.

Description of key information

LC50 -96h (fish) =  2.58 (C.I. -) mg/L based on geometric mean measured concentrations, 96-hour, freshwater, OECD TG 203, 2018

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

2.58 mg/L

Additional information

Key study: OECD TG 203, 2018 : The acute toxicity of the test item to Zebra fish (Danio rerio) was determined in a 96 hour semi-static test according to OECD TG 203 and the China Guidelines for the Testing of Chemicals, Effects on Biotic Systems, Version 2, 203 Fish Acute Toxicity Test (2013) under GLP. Based on the results of range finding tests the nominal concentrations of 0 (control), 0.8, 1.1, 1.5, 2.2 and 3.0 mg/L (geometric series with a factor of 1.4) were selected for exposure to fish groups (n=7 per group). One control containing no test item was also performed. The test item was renewed at 24 hour intervals within a 96 hour semi-static test system in response to ensuring adequate stability of exposure to test item. Observations were made at 2, 4, 24, 48, 72 and 96 hours after the start of the exposure.During the 96-hour exposure period, there was no mortality and visible toxic signs observed in the vessels of 0 (control), 0.8, 1.1 and 1.5 mg/L groups. There was lethargy observed in the 2.2 mg/L group, but no mortality. There were lethargies observed at 3.0 mg/L, and complete mortality before the end of the test period. Analytical measurements of test item concentration were made every 24 hours, pre- and post- medium renewal and the end of the exposure by GC-FID analysis.The results showed that for the nominal concentrations of 0.80, 1.1, 1.5, 2.2 and 3.0 mg/L gave overall geometric measured concentrations that were 0.342, 0.926, 1.447, 2.155 and 3.094 mg/L, which were 42.8, 84.2, 96.5, 98.0 and 103% of nominal concentrations, respectively. Therefore, effect concentrations were based on geometric mean measured concentrations that are analytically confirmed. Trimmed Spearman-Karber method analysis was used for LC50 value estimation and 95% confidence intervals determinations, as applicable. During the definitive test the water temperature was in the 21.40-23.30 °C, pH was 7.06-7.29 and air saturation was 89.3-97.7% indicating that environmental conditions were adequately maintained. Behavioural abnormalities and biological effects were reported during the course of the study. No abnormalities were observed in the control group. The 96h median LC50 was 2.58 (C.I. -) mg/L based on geometric mean measured concentrations.