A mixture of: isomers of 2-(2H-benzotriazol-2-yl)-4-methyl-(n)-dodecylphenol; isomers of 2-(2H-benzotriazol-2-yl)-4-methyl-(n)-tetracosylphenol; isomers of 2-(2H-benzotriazol-2-yl)-4-methyl-5,6-didodecyl-phenol. n=5 or 6

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:

06.01. - 27.02.1986

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: OECD guideline study, study was conducted under GLP like quality assurance.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

adopted 1984

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Sampling method: samples for analysis were taken at 0h and 96h exposure.
- Sample storage conditions before analysis: not specified

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Calculated amounts of stock solution to produce the desired test concentrations were given into the water and honogeneously distributed. The fishes were then transfered into the aquaria.
- Controls:Blank : Water
Vehicle :
- Chemical name of vehicle: Tetrahydrofuran
- Concentration of vehicle in test medium: 887 mg/L (in the concentration used for the highest test concentration)
- Evidence of undissolved material: At concentrations >100 mg/L the test substance precipitated immediately.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra fish
- Source: West-Aquariun, D-3422 Bad Lauterberg, Germany
- Length at study initiation: 22 mm (20 - 25 mm), mean value based on 10 fishes
- Weight at study initiation: 0.07g (0.05 - 0.1g), mean value based on 10 fishes
- Feeding during test: none

ACCLIMATION
- Acclimation period: 25 days
- Acclimation conditions (same as test or not): yes, same

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

194 mg CaCO3/L

Test temperature:

23 °C within +/- 1 °C

pH:

between 7.7 and 8.1

Dissolved oxygen:

between 86 mg/L and 101 mg/L

Nominal and measured concentrations:

nominal: 10, 18, 32, 58, 100 mg/L
measured (0 h): 8.3, 13.7, 27.4, 49.7, 86.9 mg/L
measured (72 h): 9.6, 15.3, 19.8, 48.8, 72.3 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass aquaria of 20 L filled with 15 L (36/22/25 cm)
- Aeration: none
- No. of organisms per vessel: 10 per concentration and control. 10 per aquarium.
- Biomass loading rate: 0.05 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dechlorinated tap water (carbon filter)
- Intervals of water quality measurement: The oxygen content, pH and temperature were measured at 0, 24, 48, 72 and 96 hours.

OTHER TEST CONDITIONS
- Photoperiod: Fluorescent light, 16 hours daily

EFFECT PARAMETERS MEASURED:
Mortalities were recorded after 24, 48, 72 and 96 hours exposure. The fishes were examined daily for symptoms of toxicity.

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 72.3 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

72.3 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: no symptoms
- Mortality of control: no
- Other adverse effects control: no
- Abnormal responses: no symptoms
- Any observations that might cause a difference between measured and nominal values: At concentrations of 100 mg/L the test item precipitated immediately.

Reported statistics and error estimates:

None.

Description of key information

There is a high probability that the product is not acutely harmful to fish.

Additional information

In a 96-h acute toxicity study, zebra-fish (Brachydanio rerio) were exposed to test item at nominal concentrations of 0 (control, solvent control) and 100 mg/L under static conditions.  The 96-h LC50 was > 100 mg/L.  The NOEC, based on mortality and sublethal effects, were ≥ 100 mg/L, respectively.  Sublethal effects were not observed. It can be concluded that the test substance is not acutely toxic to fish at the range of solubility.