Sodium 3-(2H-benzotriazol-2-yl)-5-sec-butyl-4-hydroxybenzenesulfonate

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

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)

Version / remarks:

2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: BASF 0015114756
- Expiration date of the lot/batch: Feb 20, 2021
- Purity test date: 100 area-%

Analytical monitoring:

yes

Details on sampling:

Confirmatory analysis of the test solutions was measured in aliquots of the control and 100 mg/L test item concentration collected at test initiation and at test completion. Aliquots from test completion were collected from pooled volumes of each of the test solution replicates. Approximately 40 mL of the control and each test
item concentration were collected in ~40 mL amber glass bottles and stored refrigerated (2°C to 8°C) until analysis.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: As the test item is soluble in water, a stock solution was prepared at 100 mg test item/L. To prepare the 100 mg/L stock solution, the test item was weighed on a watchglass and added directly to ~500 mL (i.e., half volume) of Daphnia magna water (dilution water) in a 1 L glass volumetric flask, and the volume topped up to 1 L with Daphnia magna water. The 100 mg/L stock solution was mixed using a magnetic stir plate for 12 minutes.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: AB170418
- Age at study initiation (mean and range, SD): < 24h
- Method of breeding:
- Source: iIn-house culture; original culture was obtained from Aquatic BioSystems (Fort Collins, CO) on April 18, 2017 (AB170418)
- Feeding during test : no

ACCLIMATION
- Health during acclimation (any mortality observed): 23.3% in 7 days preceding the test.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

104 mg/L as CaCO3

Test temperature:

20 - 20.5 °C

pH:

7.6 - 8.2

Dissolved oxygen:

8.8 mg/L

Conductivity:

345 µS/cm

Nominal and measured concentrations:

Nominal: 100 mg/L
Measured: 88.9 mg/L: The biological endpoints were assessed based on the nominal concentration of the test item as the measured concentration of the test item was within 80% to 120% of the nominal concentration.

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 mL glass beakers covered with plexiglas containg 200 mL test solution
- Aeration: none
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: according to guideline
- Culture medium different from test medium: no
- Intervals of water quality measurement: Dissolved oxygen, temperature, and pH at test initiation and test completion; Conductivity at test initiation

OTHER TEST CONDITIONS
- Photoperiod: 16h light: 8h dark
- Light intensity: 455 - 530 lux

EFFECT PARAMETERS MEASURED : Immobility was recorded after 24 and 48h expsoure time.

RANGE-FINDING STUDY
A preliminary range finding test was conducted (non-GLP) using nominal concentrations of 0, 0.01, 0.1, 1, 10, and 100 mg test item/L. As the test item is soluble, the test solutions were prepared as dilutions of a 100 mg/L stock solution. The EC50 for immobilisation was estimated to be >100 mg test item/L (95% Confidence Limits: N/A), based on nominal concentrations.

Reference substance (positive control):

yes

Remarks:

zinc sulphate heptahydrate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: nominal concentration analytically verified

Details on results:

The mortality was observed in control and treatment throughout the test. At test initiation, the negative control, and 100 mg/L test item concentration appeared clear and colourless and remained unchanged for the duration of the test.

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: 48h-LC50 = 0.45 mg/L

Validity criteria fulfilled:

yes

Conclusions:

The test substance is not acutely toxic to aquatic invertebrates.

Description of key information

EC50(48h) > 100 mg/L (measured, limit test) for immobilisation of Daphnia magna (OECD 202)

Additional information

One study investigating the short-term toxicity of the test substance to aquatic invertebrates is available. The key study was performed according to GLP and OECD guideline 202 using Daphnia magna as test organism (Tamaki 2019). 100 mg/L were tested in a limit test. The nominal concentrations was analytically verified. No mortality was observed in control and control throughout the test. Thus, the 48h-EC50 value is determined to be > 100 mg/L based on nominal concentrations.