Benzotriazole

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:

26.10.1993-13.11.1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Remarks:

Due to the high stability of the substance, the missing monitoring is considered uncritical with regard to the validity of the test concentration over time.

Vehicle:

no

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: zebrafish
- Strain:
- Source: M.B. Ruysbroeck B.V. (Noordvliet 159, Maassluis)
- Age at study initiation (mean and range, SD):
- Length at study initiation (length definition, mean, range and SD): 2.7 ± 0.2 cm
- Weight at study initiation (mean and range, SD): 0.11 ± 0.02 g
- Method of breeding:
- Feeding during test
- Food type: fishes were not fed
- Amount: -
- Frequency: -

ACCLIMATION
- Acclimation period:
- Acclimation conditions (same as test or not):
- Type and amount of food:
- Feeding frequency:
- Health during acclimation (any mortality observed):

QUARANTINE (wild caught)
- Duration:
- Health/mortality:

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

210 mg/L (based on CaCO3)

Test temperature:

24.3 - 25.4 °C

pH:

7.2 - 8.2

Dissolved oxygen:

> 6.6 mg/L

Nominal and measured concentrations:

32, 56, 100, 180, and 320 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 2 L beaker
- Material, size, headspace, fill volume: all-glass, 1.5 L medium
- Aeration: slightly aerated
- Renewal rate of test solution (frequency/flow rate): daily
- No. of organisms per vessel: 10 fishes
- No. of vessels per concentration (replicates):
- No. of vessels per control (replicates):

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
- Total organic carbon:
- Particulate matter:
- Metals:
- Pesticides:
- Chlorine:
- Alkalinity:
- Ca/mg ratio:
- Conductivity:
- Culture medium different from test medium:
- Intervals of water quality measurement:

OTHER TEST CONDITIONS
- Adjustment of pH: no adjustment
- Photoperiod: 16 / 8 (light /dark)
- Light intensity:

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality, behaviour (0, 24, 48, 72, 96 h)

TEST CONCENTRATIONS
- Spacing factor for test concentrations:
- Justification for using less concentrations than requested by guideline:
- Range finding study
- Test concentrations:
- Results used to determine the conditions for the definitive study:

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

240 mg/L

95% CI:

>= 180 - <= 320

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

240 mg/L

95% CI:

>= 180 - <= 320

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

180 mg/L

95% CI:

>= 163 - <= 221

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

180 mg/L

95% CI:

>= 154 - <= 210

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

320 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Sublethal observations / clinical signs:

 

Time (h)	Nominal concentration of test substance (mg/L)
	0	32	56	100	180	320
0	10 (a)	10 (a)	10 (a)	10 (a)	10 (a)	10 (a)
24	10 (a)	10 (b)	10 (b)	10 (b)	10 (c)	10 (d)
48	10 (a)	10 (b)	10 (b)	10 (b)	10 (c)	0
72	10 (a)	10 (b)	10 (b)	10 (b)	6 (c)	0
					4 (d)
96	10 (a)	10 (b)	10 (b)	10 (b)	5 (c)	0
					1 (d)

 

(a)  Condition of all fish, visually assessed, normal (=good).

(b)  Condition of all fish, visually assessed, equal to that of the control fish

(c)   Number of fish with disturbed equilibrium

(d)  Number of dead fish

Validity criteria fulfilled:

yes

Remarks:

Although test substance concentration was not analytically monitored during semi-static test stable concentrations (> 80 % nominal concentration) were assumed due to stability data of the substance

Conclusions:

Based on experimental observations an effect concentration LC50(96 h) = 180 mg/L (95 % c.i. 154 - 210 mg/L) has been calculated. Notwithstanding the uncertainties with regard to the substance stability, the study has been considered reliable and adequate for regulatory purposes.

Executive summary:

The acute toxicity of the test substance to the fresh-water fish species Brachydanio rerio was determined in an OECD guideline study according to GLP. The test was carried out under semi-static conditions with daily replacement of the test solutions and with 10 fish for the control medium and each concentration. The exposure duration was 96 hours.

The nominal concentrations tested were 32, 56, 100, 180, and 320 mg/L. All test solutions were completely clear (visually assessed) throughout the test.

Description of key information

Key value for freshwater was selected from OECD guideline 203 study with Danio rerio.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

180 mg/L

Additional information

Besides the OECD study with D. rerio, two new publications on FET Tests were considered relevant. Durjava et al. investigated the effects of 1H-Benzotriazole on fish embryos after 72 hours. In three series a high variability in effect concentrations was seen (0.67 - 16 mg/L). Damalas et at. also examined the effects on fish embryos and observed an effect concentration of 170 mg/L after 96 hours. Due to uncomplete reporting both studies could not be fully evaluated.