(E)-3-methyl-5-cyclopentadecen-1-one

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Study period:

From 2002-09-03 to 2003-01-23

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Remarks:

This study was performed according to OECD Guideline 211 with GLP statement. Validity criteria were fulfilled but this study comprises analytical deficiencies due to the marked decline in analytical measurements in the old media in a similar way to the fish Early-Life Stage (ELS) study. No information is available on the possible reasons of this marked decline although it would appear to be due to inappropriate analytical method and extraction technique coupled with inefficient methodology. At the time this study was performed it the performance of analytical equipment was not advanced enough to maintain stability of this difficult substance. Therefore, in the same way as the fish ELS toxicity test, performed at the same laboratory and the same year, was considered invalid on the grounds of multiple technical flaws, this study is also considered invalid for related reasons.

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Deviations:

no

Principles of method if other than guideline:

not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

Inspected on 28 February 2000. Signed on 26 April 2000

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0.0040, 0.013, 0.040, 0.13, and 0.40 mg/L
- Sampling method: On a daily basis, the numbers of live and dead of the parental generation, the numbers of live and dead filial Daphnia and the number of discarded unhatched eggs were counted. An assessment was also made of the general condition and size of the parental Daphnia as compared with the controls. The number of Daphnia with eggs or young in the brood pouch was determined at each media renewal. Young daphnids were considered to be dead if no sign of movement was apparent during microscopic examination. Adult Dapnhia which were unable to swim for approximately 15 seconds after gentle agitation were considered to be dead. At the end of the test, the length of each surviving parent animal was determined.
- Sample storage conditions before analysis: no data.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: An amount of test material (2.20 g) was dispersed in 11 L of reconstituted water and stirred with a propeller stirrer for a period of 24H at 25°C. After 24h stirring, the mixture was cooled to 21°C prior to filtration through a Gelman Suporcap filter (0.2 µm), initial 5 L of filtrate discarded to pre-condition the filter, to give a saturated solution of approximately 0.90 mg/L. Aliquots of the saturated solution (8.8, 28.8, 88, 288, and 888 mL) were each separately dispersed in a final volume of 2L of reconstituted water to give the nominal test concentrations of 0.0040, 0.013, 0.040, 0.13, and 0.40 mg/L.
- Eluate: reconstituted water
- Differential loading: cf. method.
- Controls: Control group was maintained under identical conditions but not exposed to the test material.
- Evidence of undissolved material (e.g. precipitate, surface film, etc): none

The test concentrations were prepared from a saturated solution of the test material. A study to Determine the General Physico-chemical Properties of the test material (Safephann Laboratories Project Number: 161/279) showed a water solubility value of 0.899 mg/l and pre-study solubility work showed measured values for a saturated solution of the test material of 0.90 mg/l. Therefore, the saturated solution was allocated a nominal test concentration of 0.90 mg/l for the purposes of the definitive test.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: daphnids
- Strain/clone: no data
- Justification for species other than prescribed by test guideline: not applicable
- Source: in-house laboratory cultures.
- Age of parental stock (mean and range, SD): no data
- Feeding during test: yes
- Food type: algae (Chlorella sp.)
- Amount: no data
- Frequency: daily

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Remarks on exposure duration:

none

Post exposure observation period:

no data

Hardness:

243-283 mg/L as CaCO3

Test temperature:

21°C

pH:

7.6-8.5

Dissolved oxygen:

8.1-8.5 mg O2/L

Salinity:

not applicable

Nominal and measured concentrations:

- nominal conc.: 0.0040, 0.013, 0.040, 0.13, and 0.40 mg/L
-measured conc. (TWM measured concentrations) : 0.0011, 0.00331, 0.011, 0.045, and 0.13 mg/L. See table 6.1.4/2 in "Any other information on results incl. tables".

Details on test conditions:

TEST SYSTEM
- Test vessel: 150 mL glass flasks
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: 100 mL
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): 3 times per week (days 2, 5, 7, 9, 12, 14, 16, and 19)
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10
- Biomass loading rate: no data

OTHER TEST CONDITIONS
- Adjustment of pH: no data
- Photoperiod: 16:8
- Light intensity: 548-585 lux

Reference substance (positive control):

no

Duration:

14 d

Dose descriptor:

EC50

Effect conc.:

0.022 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

immobilisation

Remarks on result:

other: 0.011-0.045

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

0.022 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

immobilisation

Remarks on result:

other: 0.011-0.045

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

0.022 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: 0.011-0.045

Dose descriptor:

LOEC

Effect conc.:

0.045 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Dose descriptor:

NOEC

Effect conc.:

0.011 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

See table 6.1.4/1 in "Any other information on results incl. tables"

Results with reference substance (positive control):

not applicable.

Reported statistics and error estimates:

not applicable.

Table 6.1.4/1: number of live young produced per adult (non-cumulative).

Time-weighted Mean Measured test concentration (mg/L)	Day
	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21
Control	0	0	0	0	0	0	5	6	7	8	1	4	7	10	7	9	6	6	9	7	9
0.0011	0	0	0	0	0	0	4	6	7	2	0	6	10	11	7	8	6	9	10	9	8
0.0031	0	0	0	0	0	0	6	6	6	2	2	6	8	9	9	10	6	6	12	7	9
0.011	0	0	0	0	0	0	6	6	6	0	0	6	10	10	9	9	7	6	12	7	9
0.045	0	0	0	0	0	0	0	a/d	-	-	a/d	-	-	-	-	-	-	-	-	-	-
0.13	0	0	0	0	0	0	a/d	-	-	-	a/d	-	-	-	-	-	-	-	-	-	-

Table 6.1.4/2: Measured concentrations

Sample	Nominal concentration (mg/L)	Concentration found (mg/L)	Expressed as a percent of the nominal concentration (%)
Day 0	Control 0.0040 0.013 0.040 0.13 0.40 1.0	<LOQ 0.00474 0.0141 0.0351 0.120 0.374 0.833	- 119 109 88 92 94 83
Day 2 Old media	Control 0.0040 0.013 0.040 0.13 0.40	<LOQ <LOQ <LOQ 0.00337 0.0170 0.0181	- - - 8 13 12
Day 2 Fresh media	Control 0.0040 0.013 0.040 0.13 0.40 1.0	<LOQ 0.00257 0.0111 0.0301 0.0955 / 0.106* 0.307 / 0.351* 0.639 / 0.691 *	- 64 85 75 73 / 82* 77 / 88* 64 / 69*
Day 5 Old media	Control 0.0040 0.013 0.040 0.13 0.40	<LOQ <LOQ <LOQ 0.00100 0.00684 0.0237	- - - 3 5 6
Day 5 Fresh media	Control 0.0040 0.013 0.040 0.13 0.40 1.0	<LOQ 0.00426 0.0118 0.0327 0.120 0.325 0.776 / 0.733*	- 107 91 82 92 81 78 / 73*
Day 7 Old media	Control 0.0040 0.013 0.040 0.13 0.40	<LOQ <LOQ <LOQ 0.00452 0.0190 0.0580	- - - 11 15 15
Day 7 Fresh media	Control 0.0040 0.013 0.040 0.13 1.0	<LOQ 0.00394 0.0123 0.0348 0.106 0.765 / 0.747*	- 99 95 87 82 77 / 75*
Day 9 Old media	Control 0.0040 0.013 0.040 0.13	<LOQ <LOQ 0.00104 0.00489 0.0117	- - 8 12 90
Day 9 Fresh media	Control 0.0040 0.013 0.040 1.0	<LOQ 0.000930 / 0.00219* 0.00598 / 0.00585* 0.0225 / 0.0206* 0.619 / 0.587*	- 23 / 55* 46 / 45* 56 / 51* 62 / 59*
Day 12 Old media	Control 0.0040 0.013 0.040	<LOQ <LOQ <LOQ <LOQ	- - - -
Day 12 Fresh media	Control 0.0040 0.013 0.040 1.0	<LOQ 0.00811 / 0.00273* 0.00951 / 0.0103* 0.0394 0.886	- 203 / 68* 73 / 79* 99 89
Day 14 Old media	Control 0.0040 0.013 0.040	<LOQ <LOQ <LOQ 0.00359	- - - 9
Day 14 Fresh media	Control 0.0040 0.013 0.040 1.0	<LOQ 0.00263 / 0.00246* 0.00807 / 0.00770* 0.0264 / 0.0252* 0.542 / 0.653*	- 66 / 61* 62 / 59* 66 / 63* 54 / 65*
Day 16 Old media	Control 0.0040 0.013 0.040	<LOQ <LOQ 0.00152 0.00367	- - 12 9
Day 16 Fresh media	Control 0.0040 0.013 0.040 1.0	<LOQ 0.00212 / 0.00255* 0.00968 / 0.00958* 0.0250 / 0.0283* 0.520 / 0.526*	- 53 / 64* 74 / 74* 62 / 71* 52 / 53*
Day 19 Old media	Control 0.0040 0.013 0.040	<LOQ <LOQ <LOQ 0.00149	- - - 4
Day 19 Fresh media	Control 0.0040 0.013 0.040 1.0	<LOQ 0.00304 0.0107 0.0326 0.822	- 76 82 81 82
Day 21 Old media	Control 0.0040 0.013 0.040	<LOQ <LOQ 0.00171 0.00519	- - 13 13

Validity criteria fulfilled:

yes

Conclusions:

The 14 and 21 -day EC50(immobilisation), and 21 -day EC50(reproduction) values were calculated to be 0.022 mg/L. The LOEC was considered to be 0.045 mg/L on the basis that at this test concentration significant mortalities were observed. The NOEC was considered to be 0.011 mg/L on the basis that at this test concentration there were no mortalities (immobilisation) observed in the parental generation and that there were no significant differences between control and the 0.011 mg/L test group in terms of number of live young produced per adult by day 21.

Executive summary:

A study was performed to assess the effect of the test material on the reproduction of Daphnia magna over 21 -day period. The method followed that described in the OECD guidelines 211.

Daphnids were exposed to an aqueous solution of the test material over a range of time-weighted mean measured test concentrations of 0.0011, 0.0031, 0.011, 0.045, and 0.13 mg/L (nominal test concentrations of 0.0040, 0.013, 0.040, 0.13, and 0.40 mg/L) for a period of 21 days. The test concentrations were prepared from a saturated solution of the test material. The pre-study solubility work showed measured values for a saturated solution of the test material of 0.90 mg/L. The variability in the measured test concentrations of the saturated solutions was considered to be due to slight variations in preparation of the saturated solution, such as small differences in stirring rate and water quality.

Given the variability shown in the measured test concentrations of the fresh test media and the marked decline shown in the old or expired test samples it was considered appropriate to base the results of the test on the time-weighted mean measured test concentrations. The time-weighted mean measured test concentrations were calculated to be 0.0011, 0.0031, 0.011, 0.045, and 0.13 mg/L.

The 14 and 21 -day EC50(immobilisation), and 21 -day EC50(reproduction) values were calculated to be 0.022 mg/L.

The LOEC was considered to be 0.045 mg/L on the basis that at this test concentration significant mortalities were observed.

The NOEC was considered to be 0.011 mg/L on the basis that at this test concentration there were no mortalities (immobilisation) observed in the parental generation and that there were no significant differences between control and the 0.011 mg/L test group in terms of number of live young produced per adult by day 21.

Validity criteria were fulfilled but this study comprises analytical deficiencies due to the marked decline in analytical measurements in the old media in a similar way to the fish Early-Life Stage (ELS) study. No information is available on the possible reasons of this marked decline although it would appear to be due to inappropriate analytical method and extraction technique coupled with inefficient methodology. At the time this study was performed it the performance of analytical equipment was not advanced enough to maintain stability of this difficult substance. Therefore, in the same way as the fish ELS toxicity test, performed at the same laboratory and the same year, was considered invalid on the grounds of multiple technical flaws, this study is also considered invalid for related reasons.

Reference 2

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

Based on structural similarity (the source substance is one of the constituents of the target substance, together with isomers), both substances are not expected to be ecotoxicologically different. Therefore the result of the study is considered suitable for the target substance.
Further information is included in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

121 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

other: intrinsic rate of population increase

Remarks on result:

other: 95% CL: 40-160 µg a.i./L

Conclusions:

(from analogue) the substance has a chronic adverse effect on Daphnia magna. The lowest EC10 value was determined at 121 µg test item/L TWM, for the intrinsic rate of population increase.

Executive summary:

A 21-day semi-static exposure to the analogue test substance at different concentrations with renewal of the test solutions three times a week was conducted according to OECD guideline 211. Untreated control replicates were run in parallel. Each treatment group consisted of 10 replicates with one daphnid each (individual exposure). Effects on growth (adult length at test termination) and reproductive performance were investigated. Test item concentrations were measured at fresh and aged test solutions. The mean solubility of 1120.8 μg test item/L was determined under the test conditions.

The average time weighted means (TWM) of measured initial and aged concentrations at test solution renewal were 21.0, 40.6, 89.8, 155.0 and 271.7 µg test item/L, corresponding with 30.0, 29.0, 32.0, 27.6 and 24.2% of the nominal concentrations.

TWM test concentrations up to 271.7 µg test item/L did not affect survival of adults statistically significant. However, with 50% mortality at test end in the highest concentration a relevant effect occurs (NOEC survival = 155 µg test item/L TWM). The EC10 and EC50 survival of 232 and 272 µg test item/L TWM were determined, respectively. No clinical sign was observed for the survived individuals.

Adult growth (body length) was affected significantly starting at 155 µg test item/L TWM. The NOEC adult growth was found to be 89.8 µg test item/L TWM. The EC10 and EC50 adult growth of 165 and > 272 µg test item/L TWM were determined, respectively.

The age at first brood was affected significantly starting at 155 µg test item/L TWM. The NOEC first brood was found to be 89.8 µg test item/L TWM.

Adult reproduction was affected significantly starting at 271.7 µg test item/L TWM. The NOEC reproduction was found to be 155 µg test item/L TWM. The EC10 and EC50 reproduction of 192 and 253 µg test item/L TWM were determined, respectively.

Intrinsic rate of population increase was affected significantly starting at 155 µg test item/L TWM. The corresponding NOEC was found to be 89.8 µg test item/L TWM. The EC10 and EC50 intrinsic rate of population increase of 121 and 258 µg test item/L TWM were determined, respectively.

In conclusion, the test substance has a chronic adverse effect on Daphnia magna. Adult growth, age of first brood, and intrinsic rate of population increase were affected starting at 155 µg test item/L time weighted means (TWM) (LOEC). The relevant NOEC adult growth, age of first brood and intrinsic rate of population increase is 89.8 µg test item/L TWM. The relevant EC50 (reproduction) is 253 µg test item/L TWM. Finally, the lowest EC10 value was determined at 121 µg test item/L TWM, for the intrinsic rate of population increase. A similar result is anticipated for the target substance.

Reference 3

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 2009-03-09 to 2009-03-30

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

This study was performed according to OECD Guideline 211 with GLP certificate. All validity criteria were fulfilled and no deviations were observed.

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
The test substance is not the registered substance. Read-across is justified as data relates to a monoconstituent corresponding to the major isomer component of the registered substance. This substance is present at 35 to 50% of the isomer compositions of the registered substance and the other isomers forms are not expected to be ecotoxicologically different.

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
[Describe why the read-across can be performed (e.g. common functional group(s), common precursor(s)/breakdown product(s) or common mechanism(s) of action]

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
[Provide here, if relevant, additional information to that included in the Test material section of the source and target records]

3. ANALOGUE APPROACH JUSTIFICATION
[Summarise here based on available experimental data how these results verify that the read-across is justified]

4. DATA MATRIX

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

Inspected from 23 to 25 August 2006 / Signed on 21 March 2007

Specific details on test material used for the study:

- Water solubility: 100 µg/L
- Vapour pressure: 0.04 Pa at 25°C
- Partition coefficient (log Pow): 6.57 (measured)
- Relative density (20°C): 0.931-0.939 g/cm3
- Storage condition of test material: Room temperature, dry, well ventilated. Keep container closed and filled, keep away from heat sources, protect against high temperature. Do not re-use empty container.
- Storage stability: stable under normal conditions, avoid oxidizing materials

Analytical monitoring:

yes

Details on sampling:

- Concentrations: At test start and at each renewal samples of all treatments were taken from the test solution preparation just before distributing it to the 10 replicates. At the renewals samples of the aged test solution were taken from each vessel, pooled per concentration and measured.
- Sampling method: At the start and at each renewal sub-sample from each freshly prepared test solution were taken for chemical analysis. Additionally pooled samples were taken from each aged test series/concentration. The samples for analysis were filled into 40 mL sample vials. The vials were filled up to the brim to prevent the loss of Muscenone dextro into the headspace of the vials.
For sample preparation, aliquot samples ranging from 0.1 to 5.0 mL were pipetted into 8 mL test tubes, sample volumes less than 5 mL were filled up to 5 mL with purified water. Then 100 µL of the IS working solution and 400 µL cyclohexane were added. The mixtures were shaken thoroughly by hand and additionally for 10 min on a horizontal shaker (about 200 strokes/min). For a rapid phase separation the tubes are centrifuged at 2000 rpm for 2 minutes. The organic supernatants (250 µL aliquots) were transferred into the autosampler vials using disposal Paster pipettes, aliquots of 1µL were analysed by GC/MS.
- Sample storage conditions before analysis: no data

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 200 mg (214 µL) of test substance were given into 2 L dilution water in a 2 L flask with a drain port near the bottom. The preparation was stirred at room temperature for 48 h avoiding very strong stirring due to avoiding the generation of fine droplets. After 48 hours the preparation was left for around 18 hours (overnight) to enable droplets to move to the surface of the solution. Then, 200 mL of the aqueous phase were drained off and discarded. The following 600 mL were used for the test preparation without filtration as the highest test concentration. Because adsorption of the test item on filter material cannot be excluded, it is preferred to use test solutions without filtration. The next 1000 mL were used to prepare the dilution series for the further test concentrations. The original eluate was diluted with dilution water by a factor of 2 to obtain the other 4 treatments.
- Eluate: dilution water
- Differential loading: no data
- Controls: yes, the control consists of dilution water only.
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): not applicable
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): not applicable
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no data

The test item is a liquid of poor water solubility. Since the use of a dispersant should be avoided, test solutions were prepared in dilution water as described above to obtain the maximum dissolved concentration of the test substance.

The mean solubility of 1120.8 μg test item/L was determined under the test conditions.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnids
- Strain/clone: no data
- Justification for species other than prescribed by test guideline: not applicable
- Source: German Federal Environment Agency, Institut für Wasser-, Boden- und Lufthygiene. Specimens used in the test were bred in the laboratory of hte Fraunhofer IME.
- Age of parental stock (mean and range, SD): 4-24 hours old at test start.
- Feeding during test: yes.
- Food type: suspensions of unicellular alga Desmodesmus subspicatus
- Amount: about 7 to 15 mg C/L
- Frequency: daily

ACCLIMATION
- Acclimation period: no data
- Acclimation conditions (same as test or not): same as test
- Type and amount of food: algal suspension (Desmodesmus subspicatus) and LiquizellR (HOBBY).
- Feeding frequency: daily
- Health during acclimation (any mortality observed): no data

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES: no data

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Remarks on exposure duration:

none

Post exposure observation period:

No

Hardness:

total hardness = 1.0 mmol/L

Test temperature:

With 20.4-21.0°C throughout the test the permitted range of 18-22°C (with a variance of less than 2°C) was maintained.

pH:

The pH values throughout the test were within a range of 8.0 - 8.7 at all treatment levels.

Dissolved oxygen:

The oxygen saturation was between 6.4 mg/L and 9.5 mg/L.

Salinity:

Not applicable

Nominal and measured concentrations:

Nominal concentrations: 6.25, 12.5, 25, 50 and 100 mg test item/L.
Measured concentrations: 21.0, 40.6, 89.8, 155.0 and 271.7 µg test item/L (corresponding with 30, 29, 32, 27.6 and 24.2% of the nominal concentrations).

Details on test conditions:

TEST SYSTEM
- Test vessel: round glass beakers
- Type (delete if not applicable): the containers were covered with glass panes
- Material, size, headspace, fill volume: glass, 50 mL
- Aeration: without aeration
- Type of flow-through (e.g. peristaltic or proportional diluter): not applicable
- Renewal rate of test solution (frequency/flow rate): test solution was exchanged daily.
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10
- No. of vessels per vehicle control (replicates): not applicable
- Biomass loading rate: no data

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: purified drinking water was used as holding- and dilution water. The purification included filtration with activated charcoal, passage through a lime-stone column and aeration. To avoid copper contamination, plastic water pipes are used for the testing facilities.
- Total organic carbon: no data
- Particulate matter: no data
- Metals: no data
- Pesticides: no data
- Chlorine: no data
- Alkalinity: 2.0-2.2 mmol/L
- Ca/mg ratio: no data
- Conductivity: 261.2-273.7 µS/cm
- Salinity: no data
- Culture medium different from test medium: no
- Intervals of water quality measurement: no data

OTHER TEST CONDITIONS
- Adjustment of pH: no data
- Photoperiod: light/dark cycle of 16/8 hours
- Light intensity: the light intensity did not exceed 15-20 µE/(m²*s) or 1125-1500 lx.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Effects on growth (adult length at test termination) and reproductive performance were investigated.

VEHICLE CONTROL PERFORMED: not applicable

RANGE-FINDING STUDY: Not applicable

Reference substance (positive control):

no

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

232 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

(parental survival)

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

165 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

growth

Remarks:

(length on day 21)

Remarks on result:

other: 95% CL: 145-181 µg a.i./L

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

192 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

other: cumulative offspring per female

Remarks on result:

other: 95% CL: 185-197 µg a.i/L

Key result

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

121 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

other: intrinsic rate of population increase

Remarks on result:

other: 95% CL: 40-160 µg a.i./L

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

155 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

(parental survival)

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

89.8 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

growth

Remarks:

(length on day 21)

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

89.8 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

other: age at first brood

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

155 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

other: cumulative offspring per female

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

89.8 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

other: intrinsic rate of population increase

Details on results:

- Test item concentration:
The mean measured test item concentrations of the freshly prepared test solutions of the active ingredient (initial concentrations) were between 100% and 128.4% of nominal (based on the solubility under test conditions). During the time interval until renewal of the test solution, active ingredient concentrations decreased considerably to 2.7-3.6% of nominal. The average time weighted means (TWM) of measured initial and aged concentrations at test solution renewal were 21.0, 40.6, 89.8, 155.0 and 271.7 µg test item/L, corresponding with 30.0, 29.0, 32.0, 27.6 and 24.2% of the nominal concentrations.

- Survival, growth and reproduction data:
See table 6.1.4/1 in "Any other information on results incl. tables"

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

For each endpoint, the NOEC, LOEC and if possible the EC50 and EC10 were determined. Calculations were performed with the computer software ToxRat. A NOEC was calculated by using ANOVA following by Williams' test or an appropriate non-parametric test suggested by the ToxRat program. When the test results showed a loading-response relationship, the data were analysed by regression to determine the EC50 including the 95% confidence interval as well as the EC10 using Probit-analysis assuming log-normal distribution of the values.

Table 6.1.4/1: Survival, growth and reproduction data

Concentration	Parental survival	Growth (length on Day 21)	Age of first brood	Cumulative offspring per female	Intrinsic rate of population increase
TWM (µg test item/L)	(%)	Mean +/- SD (days)	Mean +/- SD (days)	Mean +/- SD (Ind.)	Mean +/- SD (Ind./day)
Control	100	4.85 +/- 0.32	8.5 +/- 0.9	85.4 +/- 8.2	0.358 +/- 0.041
21.0	100	4.86 +/- 0.27	8.7 +/- 1.1	81.0 +/- 14.1	0.337 +/- 0.035
40.6	100	4.88 +/- 0.30	8.5 +/- 1.1	96.2 +/- 19.4	0.350 +/- 0.040
89.8	100	4.71 +/- 0.33	8.9 +/- 1.0	85.2 +/- 9.4	0.326 +/- 0.025
155.0	100	4.48 +/- 0.17*	10.1 +/- 0.7*	84.4 +/- 8.0	0.299 +/- 0.016*
271.7	50	3.41 +/- 0.44*	13.3 +/- 1.6*	32.0 +/- 20.6*	0.162 +/- 0.057*

Table 6.4.4/2: Effect summary table, based on concentrations (µg a.i./L) calculated from time weighted mean concentrations

Concentration	Parental survival	Growth (length on day 21)	Age at first brood	Cumulative offspring per female	Instrinsic rate of increase
EC50 (95% CL)	272 (n.d.)	> 272 (> 272)	/	253 (252 - 255)	258 (213 - >272)
EC10 (95% CL)	232 (n.d.)	165 (145 - 181)	/	192 (185 - 197)	121 (40 – 160)
NOEC	155.0*	89.8	89.8	155.0	89.8

n.d. = not determined due to mathematical reasons; * Value assessed by expert knowledge

Validity criteria fulfilled:

yes

Conclusions:

The test substance has a chronic adverse effect on Daphnia magna. The lowest EC10 value was determined at 121 µg test item/L TWM, for the intrinsic rate of population increase.

Executive summary:

A 21 -day semi-static exposure to the test substance at different concentrations with renewal of the test solutions three times a week was conducted according to OECD guideline 211. Untreated control replicates were run in parallel. Each treatment group consisted of 10 replicates with one daphnid each (individual exposure). Effects on growth (adult length at test termination) and reproductive performance were investigated. Test item concentrations were measured at fresh and aged test solutions. The mean solubility of 1120.8 μg test item/L was determined under the test conditions.

The average time weighted means (TWM) of measured initial and aged concentrations at test solution renewal were 21.0, 40.6, 89.8, 155.0 and 271.7 µg test item/L, corresponding with 30.0, 29.0, 32.0, 27.6 and 24.2% of the nominal concentrations.

TWM test concentrations up to 271.7 µg test item/L did not affect survival of adults statistically significant. However, with 50% mortality at test end in the highest concentration a relevant effect occurs (NOEC survival = 155 µg test item/L TWM). The EC10 and EC50 survival of 232 and 272 µg test item/L TWM were determined, respectively. No clinical sign was observed for the survived individuals.

Adult growth (body length) was affected significantly starting at 155 µg test item/L TWM. The NOEC adult growth was found to be 89.8 µg test item/L TWM. The EC10 and EC50 adult growth of 165 and > 272 µg test item/L TWM were determined, respectively.

The age at first brood was affected significantly starting at 155 µg test item/L TWM. The NOEC first brood was found to be 89.8 µg test item/L TWM.

Adult reproduction was affected significantly starting at 271.7 µg test item/L TWM. The NOEC reproduction was found to be 155 µg test item/L TWM. The EC10 and EC50 reproduction of 192 and 253 µg test item/L TWM were determined, respectively.

Intrinsic rate of population increase was affected significantly starting at 155 µg test item/L TWM. The corresponding NOEC was found to be 89.8 µg test item/L TWM. The EC10 and EC50 intrinsic rate of population increase of 121 and 258 µg test item/L TWM were determined, respectively.

In conclusion, the test substance has a chronic adverse effect on Daphnia magna. Adult growth, age of first brood, and intrinsic rate of population increase were affected starting at 155 µg test item/L time weighted means (TWM) (LOEC). The relevant NOEC adult growth, age of first brood and intrinsic rate of population increase is 89.8 µg test item/L TWM. The relevant EC50 (reproduction) is 253 µg test item/L TWM. Finally, the lowest EC10 value was determined at 121 µg test item/L TWM, for the intrinsic rate of population increase.

Description of key information

Read-across, OECD Guideline 211, GLP, key study, validity 1:

21d-EC10 (Daphnia magna) = 0.121 mg/L based on intrinsic rate of population increase and time weighted mean measured concentrations.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.121 mg/L

Additional information

Two studies are available to assess the long-term toxicity of the registered substance to aquatic invertebrates. The first study was performed on the registered substance and the other one on a supporting substance. This supporting substance is considered adequate for read-across purposes (see IUCLID section 13 for justification).

The first study (Safepharm, 2003), performed on the registered substance, was performed according to OECD Guideline 211 with GLP statement. Validity criteria were fulfilled but this study comprises analytical deficiencies due to the marked decline in analytical measurements in the old media in a similar way to the fish Early-Life Stage (ELS) study. No information is available on the possible reasons of this marked decline although it would appear to be due to inappropriate analytical method and extraction technique coupled with inefficient methodology. At the time this study was performed in the performance of  analytical equipment was not advanced enough to maintain stability of this difficult substance. Therefore, in the same way as the fish ELS toxicity test, performed at the same laboratory and the same year, was considered invalid on the grounds of multiple technical flaws, this study is also considered invalid for related reasons. If nominal rather than measured values are considered, the 21d-LOEC is equivalent to 0.13 mg/L as significant mortalities were observed.

This value is in accordance with the 21d-LOEC value determined at 0.155 mg/L in the more recent Daphnia magna reproduction test (Fraunhofer, 2009), performed on the read-across substance. This source substance is one of the constituents of the registered (target) substance, together with isomers. The source substance is a mono-constituent, individual optical isomer, while the registered substance is defined as a multi-constituent, with three pairs of racemate. This study was performed according to OECD Guideline 211 with GLP statement, in a semi-static system and was considered valid and concentrations of test substance were more satisfactorily maintained during the test. According to the results of this study, the lowest chronic EC10 value, based on intrinsic rate of population increase, was determined at 0.121 mg/L, based on time weighted mean measured concentrations.

Therefore, based on these observations, the key value used for chemical safety assessment is a 21d-EC10 value at 0.121 mg/L, obtained for the read-across substance, which is in accordance with the expected result on the registered substance.