Benzene, C10-13-alkyl derivs.

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:

03 Nov 1998 to 19 Nov 1998

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 204 (Fish, Prolonged Toxicity Test: 14-day Study)

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Sampling was done on test solutions on days 1 and 14 of the test. Samples were taken from the test solution both before treatment, and after 24 hrs of treatment.

Vehicle:

no

Details on test solutions:

1 g/L of LAB was added to reconstituted water; this was stirred for 24 hours and then transferred to a separatory funnel and allowed to stand 4 hours. The lower portion was slowly filtered (0.45 µm HV Millipore) and used for testing and for dilutions (2 : 1 and 1 : 1).

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Source: YARA Tropical Fish
- Average length at study initiation: 3 cm
- Average weight at study initiation: 0.27 g

FEEDING DURING TEST
- Food type: Mangime SERA DISKUS
- Amount: 2% per initial fish weight
- Frequency: Daily

ACCLIMATION
- Acclimation period: 14 days
- Health during acclimation (any mortality observed): No mortality after the first 48 hrs

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

14 d

Hardness:

246 mg/L as CaCO3

Test temperature:

24.2°C

pH:

7.4

Dissolved oxygen:

8.0 mg O2/L

Nominal and measured concentrations:

- Nominal concentration: 0, 5, 6.5, and 10 µg/L
- Initial measured concentration (0 hrs): 5.53, 6.64, and 10.18 µg/L
- Measured concentration after treatment (24 hrs): 0.43, 1.37, and 2.68 µg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers
- Fill volume: 5 L
- Renewal rate of test solution (frequency/flow rate): Daily
- No. of organisms per vessel: 5
- No. of vessels per concentration: 2
- No. of vessels per control: 2
- Biomass loading rate: 0.54 g fish/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted water
- Ca/mg ratio: 4:1

OTHER TEST CONDITIONS
- Photoperiod: 16 hrs light/8 hrs dark
- Light source: Artificial light

EFFECT PARAMETERS MEASURED (with observation intervals if applicable)
- Daily observations were made of swimming behaviour, reaction to stimuli, discoloration, food intake, and mortality. All fish were weighed and measured before the test. Survivors were weighed at test termination.

Reference substance (positive control):

no

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

> 10 µg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

> 10 µg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Details on results:

A decrease in the test substance concentration was observed within 24 hours (day 1 and day 14), but the daily renewal of test solutions guaranteed the exposure to the test substance. No effects on the fish were observed for the concentrations tested. An overview of the results is provided in Table 1 in "Any other information on results incl. tables". Therefore, both LC50 and NOEC were determinded to be > 10 µg/L, the highest test concentration.

Sublethal observations / clinical signs:

Table 1. Result of mean body weight            

Concentration	0 (µg/L)	5 (µg/L)	7.5 (µg/L)	10 (µg/L)
Initial (g)	0.20	0.4	0.20	0.28
Final (g)	0.20	0.41	0.21	0.28

Validity criteria fulfilled:

yes

Conclusions:

Based on the findings, the 14-day LC50 for fish was determinded to be > 10 µg/L, the highest tested concentration.

Executive summary:

This study determined the prolonged short-term toxicity of the test substance to freshwater fish (Danio rerio). The test was conducted according to OECD guideline 204 and in compliance with GLP criteria. The fish were exposed for 14 days to a water accommodated fraction of 0, 5, 6.5, and 10 µg/L of the test substance. The test medium was renewed daily. Fish were monitored daily for toxicity during the study. No adverse effects were observed during the study period.

Based on the findings, the NOEC was determined to be > 10 µg/L (the highest tested concentration) and the LC50 was determined to be > 10 µg/L as well.

Description of key information

A 14-day short-term toxicity test of the test subtsance to freshwater fish (Danio rerio) was conducted according to OECD guideline No.204. The LC50 based on mortality was determinded to be > 10 µg/L, the highest tested concentration.

Additional information

The key study determined the toxicity of LAB to fish in an extended acute study. Fish were exposed for 14 days to a water accommodated fraction of 0, 5, 6.5, and 10 µg/L of test substance. The test medium was renewed daily. Fish were monitored daily for toxicity during the study for swimming behaviour, reaction to stimuli, discoloration, food intake, and mortality. All fish were weighed and measured before the test and survivors were weighed at test termination. No adverse effects were observed for the concentrations tested during the study period. A decrease in the test substance concentration was observed within 24 hours (day 1 and day 14), but the daily renewal of test solutions maintained the exposure to the test substance. Both the LOEC and NOEC were higher than the solubility concentration of > 10 µg/L/day.