2,2'-(vinylenedi-p-phenylene)bis[5-methylbenzoxazole]

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:

Preliminary test from February 26th to March 02nd, 2001; definitive test in April from 09th to 13th, 2001

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

adopted 17 July, 1992

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Version / remarks:

adopted 31 July, 1992

GLP compliance:

no

Analytical monitoring:

no

Details on test solutions:

Due to the limited water solubility of the test material the respective amount was added as an acetonic solution to the empty test vessel. After complete evaporation of the solvent, the test water was added.

Test organisms (species):

Poecilia reticulata

Details on test organisms:

TEST ORGANISM
- Common name: Guppy.
- Length at study initiation: 1 - 3 cm

BREEDING
- Vessels: parental and young fish population was held in two 250 | glass aquaria.
- Photopriod: 14h a day.
- Temperature: 23 ± 2 °C
- Medium: continuously aerated and filtered tap water from Schlieren. The bottom of the aquaria was covered with gravel (≤ 1.5 cm). Every month, one third of the total volume of the aquaria was replaced by fresh tap water.
- Feed: Sera micropan, Sera vipan (Sera apanristic GmbH, D-52525 Heinsberg, Germany) daily. The fish were last fed 24 h betore the start of the definitive test.
- Measurements: pH, conductivity, oxygen concentration and hardness of water were determined once a week. Temperature was controlled by a thermostatic heating element.
- Validity: during 7 days before the definitive test, mortality in the batch of which fish were used for the test was less than 5 %.

PREPARATION FOR THE TEST
Test fish were transferred into the test vessels about 1 h after formation of the test media.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Test temperature:

Test vessels: 20.5 - 21 °C
Control: 20.5 - 21 °C

pH:

Test vessels: 8.1 - 8.8
Control: 8.4 - 8.7

Dissolved oxygen:

Test vessels: 6.8 - 7.3 mg/l
Control: 6.9 - 7.1 mg/l

Nominal and measured concentrations:

Nominal 100 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: 1 l aquaria, all-glass.
- Aeration: yes.
- No. of organisms per vessel: 7 fish per test concentration.
- No. of vessels per concentration: one replicate.
- No. of vessels per control: one replicate.

TEST MEDIUM / WATER PARAMETERS
- Source of dilution water: tap water from Schlieren, aerated.
- Preparation: at least 1 h before the test, the test vessels were filled with the medium to allow equilibration of pH, oxygen and temperature.

OTHER TEST CONDITIONS
- Adjustment of pH: the pH was not adjusted.
- Photoperiod: 16 h photoperiod a day, supplied by overhead white fluorescent tubes.

EFFECT MEASURED
Fish were considered to be dead when they showed no reaction after touching the caudal fin or no visible breathing movements.
Based on the binominal theory, the absence of mortality of a total of seven fish provides at least 99 % confidence that the LC50 is greater than the applied nominal test concentration of 100 mg/l.

OBSERVATIONS AND MEASUREMENTS
- Oxygen, pH, temperature: prior to the addition of fish to the test medium and after 2, 24, 48, 72 and 96 h of exposure.
- Observation: observations of the fish were made after 2, 24, 48, 72 and 96 h of exposure. Mortality of the fish was recorded at the same time intervals. Dead fish were removed immediately from the test medium and weight and length recorded.

TEST CONCENTRATIONS
Range finding study
- Test concentrations: 10 and 100 mg/l, nominal.
- No. of organisms per vessel: 3 fish per test concentration.
- No. of vessels per concentration: one replicate.
- Results used to determine the conditions for the definitive study: in the pretest no mortality was observed after 96 h of exposure. Therefore, only a limit test was performed.

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

At the nominal concentration of 100 mg/l one of a total of seven fish died after 48 h of exposure. No mortality was observed in the blank control.
Other toxic effects than mortality, e.g. loss of coordination, hypo- or hyperactivity and swimming on the back, were not observed.

Based on the binominal theory, the absence of mortality provides at least 99 % confidence that the LC50 is higher than 100 mg/l.
The no-observed-effect concentration (NOEC) was equal/higher than 100 mg/l since the one fish that died is considered not to represent a significant effect as defined by the validity criteria of the test.
100 % mortality (LC100) could not be detected.

Conclusions:

LC50 (96h) > 100 mg/l (nominal)

Executive summary:

The acute lethal toxicity of test item to Poecilia reticulata (Guppy) was investigated under static exposure conditions over a period of 96 h. The only applied nominal test concentration was 100 mg/l. Due to the limited water solubility of the test material the respective amount was added as an acetonic solution to the empty test vessel. After complete evaporation of the solvent, the test water was added. No chemical analysis of the test substance concentration was conducted.

At the nominal concentration of 100 mg/l one of a total of seven fish died after 96h of exposure. No mortality was observed in the blank control.

Other toxic effects than mortality, e.g. loss of coordination, hypo- or hyperactivity and swimming on the back, were not observed.

The no-observed-effect concentration (NOEC) was higher than 100 mg/l since the one fish that died is considered not to represent a significant effect as defined by the validity criteria of the test. 100 % mortality (LC100) could not be detected. Based on the binominal theory, the absence of modality provides at least 99 % confidence that the LC50 is greater than the applied nominal test concentration of 100 mg/l.

Conclusion

LC50 (96h) > 100 mg/l (nominal)

Description of key information

Not harmful/toxic to fish, after short-term exposure.

Additional information

The acute lethal toxicity of the substance was investigated on guppy, under static exposure conditions over a period of 96 h. The only applied nominal test concentration was 100 mg/l. Due to the limited water solubility of the test material the respective amount was added as an acetonic solution to the empty test vessel. After complete evaporation of the solvent, the test water was added. No chemical analysis of the test substance concentration was conducted. At the nominal concentration of 100 mg/l one of a total of seven fish died after 96h of exposure. Other toxic effects than mortality, e.g. loss of coordination, hypo- or hyperactivity and swimming on the back, were not observed.

The no-observed-effect concentration (NOEC) was higher than 100 mg/l since the one fish that died is considered not to represent a significant effect as defined by the validity criteria of the test.

In order to support the study outcomes, data on a structural analogue, i.e. Similar Substance 01, has also been taken into conderation. The read across approach can be considered as suitable and appropriate to investigate the potential for aquatic toxicity of Fluorescent Brightener 002 (the read across approach is detailed in section 13).

The acute lethal toxicity of Similar Substance 01 was assessed in Leuciscus idus f. melanotus, under static exposure conditions. Fish were exposed to the following nominal dose levels: 0, 1, 10, 100 and 500 mg/l; no chemical analysis of the test substance concentrations was conducted. Over the whole exposure period of 96 hours, no fish died in none of the concentration groups. The behavior was unaffected in all experimental groups and did not differ from that of the control fish. The section of the fish slaughtered at the end of the experiment revealed yellow-discolored intestinal contents in all experimental groups.

In both the cases, no acute adverse effects were recorded at the highest tested dosages; thus, the substance resulted to be not harmful/toxic to fish, after short-term exposure.