Reaction mass of 1H-Benzotriazole-1-methanamine, N,N-bis(2-ethylhexyl)-6-methyl- and 2H-Benzotriazole-2-methanamine, N,N-bis(2-ethylhexyl)-5-methyl- and N,N-bis(2-ethylhexyl)-4-methyl-1H-benzotriazole-1-methylamine and 2H-Benzotriazole-2-methanamine, N,N-bis(2-ethylhexyl)-4-methyl- and N,N-bis(2-ethylhexyl)-5-methyl-1H-benzotriazole-1-methylamine

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2013-01-08 to 2013-01-10

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)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Lot/batch No.of test material: 0005408236
- Expiration date of the lot/batch: July 2014

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature, avoid temperature < 0°C

Analytical monitoring:

yes

Details on sampling:

- Concentrations: each loading level 0.500 - 1.00 - 2.00 - 4.00 - 8.00 mg/L
- Sampling method: Each loading level and the control was analytically verified at the start (0 hours) and the end of the exposure (72 hours). Sampling at the start of the exposure (0 hours) was carried out directly after preparation of the water accommodated fractions. At the end of the exposure (48 hours), samples were taken from additional replicates prepared with test media, but without daphnids. These replicates were incubated under test conditions until sampling.
- Sample storage conditions before analysis: All original samples were stored at 6 ± 2 °C until sample preparation. Prepared samples were stored at room temperature until analysis.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Water Accommodated Fraction (WAF) of the test item were prepared. Therefore, the test item was mixed with water for a prolonged period sufficient to ensure equilibration between the test item and the water phase. These dispersions were shaken for 24 h with 20 rpm at room temperature. At the completion of mixing and following a 1-h settlement period, the test item phase was separated by siphon and the test organisms exposed to the aqueous phase. Five water accommodated fractions (WAF) were prepared: 0.500 - 1.00 - 2.00 - 4.00 - 8.00 mg/L
- Controls: Five replicates (dilution water without test item) were exposed under the same conditions as the test loadings.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Waterflea, Daphnia magna Straus (Clone 5)
- Source: Institut für Wasser-, Boden- und Lufthygiene (WaBoLu)
- Breeder: Dr. U. Noack-Laboratorien, Sarstedt, Germany
- Method of cultivation: In glass vessels (2 - 3 L capacity) with approximately 1.8 L culture medium, at 20 ± 2°C, in an incubator, 16 h illumination, light intensity of max. 20 µE*m-2*s-1, pH in the range of 6 to 9. Culture medium: Elendt M4, according to ELENDT (1990), modified to a total hardness of 160 to 180 mg CaCO3/L. Feeding: At least 5 times per week ad libitum with a mix of unicellular green algae, e.g. Pseudokirchneriella subcapitata and Desmodesmus subspicatus, with an algae cell density of > 106 cells/mL.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

180 mg CaCO3/L

Test temperature:

20.8°C at the start of the study

pH:

in control at 0h: 8.16
in control at 48h: 7.42 to 7.60
loading rates at 0h: 7.96 to 8.11
loading rates at 48h: 7.49 to 7.65

Dissolved oxygen:

in control at 0h: 8.76 mg/L
in control at 48h: 6.70 to 7.60
loading rates at 0h: 8.71 to 8.91
loading rates at 48h: 5.01 to 7.62

Salinity:

467 µS/cm

Nominal and measured concentrations:

Nominal concentrations: 0.500 - 1.00 - 2.00 - 4.00 - 8.00 mg/L
Measured concentrations at test start: 0.512 - 1.07 - 2.05 - 4.14 - 8.40 mg/L
Measured concentrations at test end: 0.550 - 1.10 - 2.08 - 4.23 - 8.32 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers (4 cm ID x 7 cm H), 50 mL capacity with 20 mL test volume
- Type: covered with watch glasses
- Aeration: none
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt M4, according to ELENDT (1990), modified to a total hardness of 160 to 180 mg CaCO3/L
- Measurements: pH and O2 at the beginning and at the end of the test. Temperature, conductivity and total hardness were measures prior to the start of exposure.

OTHER TEST CONDITIONS
- Photoperiod: 16 hours daily
- Light intensity: Diffuse light, light intensity of max. 20 µE*m-2*s-1

EFFECT PARAMETERS MEASURED : Immobilization after 24 and 48 hours

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.0
- Test concentrations: Nominal: 0.500 - 1.00 - 2.00 - 4.00 - 8.00 mg/L

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

24 h

Dose descriptor:

EC10

Effect conc.:

1.96

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 1.45 - 2.38

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

4.45

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 3.99 – 5.12

Duration:

24 h

Dose descriptor:

EC100

Effect conc.:

> 8

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Not applicable

Key result

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

1.92

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 1.06 – 3.70

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

2.05

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 1.12 – 3.76

Key result

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

4

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Not applicable

Details on results:

- Mortality of control: 0%
- Any observations that might cause a difference between measured and nominal values: All tested loading levels were visually clear throughout the exposure period.

Results with reference substance (positive control):

EC50 after 24 hours of potassium dichromate = 1.69 mg/L (CI 1.41 - 2.12 mg/L)
The EC50-value of the reference item potassium dichromate after 24 h is within the prescribed concentration range of 1.0 - 2.5 mg/L of quality criteria according to AQS P 9/2 (05/1996) for daphnids clone 5 cultured in Elendt M4 medium. The EC50-value of the reference item is also within the recommended range of 0.6 - 2.1 mg/L according to OECD-Guideline 202.

Reported statistics and error estimates:

EL10- and EL50-values were calculated by sigmoidal dose-response regression. The confidence limits were calculated from the best-fit values, the standard error and the t-distribution with the software GraphPad prism5. The loading-effect relationships are presented graphically.
The EC50-value for the reference item and its confidence limits were calculated by sigmoidal dose-response regression. The confidence intervals were calculated from the best-fit values, the standard error and the t-distribution with the software GraphPad prism5.

Description of key information

Two studies investigated the effects of the test item on immobilisation of Daphnia magna.
In the GLP compliant key study according to OECD 202 guideline (BASF SE, 2013), daphnids were exposed under static conditions over 48 hours to five loading levels of 0.500 - 1.00 - 2.00 - 4.00 - 8.00 mg/L. Analytical verification of the test substance showed that the loading rates were within 80 to 120 % of the nominal levels. After 48 hours, the EC50 for immobility was 2.05 mg/L. All validity criteria were met.
In a supporting non-GLP study, Daphnia magna were exposed to the test item for 24h under static conditions. Daphnids were exposed to control, solvent control, and test item at nominal concentration of 1.0, 1.8, 3.2, 5.8, 10 mg/L for 24 h. The 24h EC50 was 1.4 mg/L. The 24h EC0 based on immobilization was 1 mg/L. Due to considerable restrictions (e.g. no analytical test item concentration verification; non-GLP; use of a solvent), the study is not reliable and disregarded in terms of chemical safety assessment.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

2.05 mg/L