Pyridinium toluene-4-sulphonate

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Version / remarks:

May 2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

July 1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Duplicate samples were taken from each treatment at the start and at the end of the two test medium renewal periods.
All samples were stored frozen (at about -20 ± 5 C) immediately after sampling.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: An aqueous solution with a nominal content of 80 % was prepared prior to the test. The test substance content of this working solution was analytically verified by HPLC to be 77.9 % (water-free). The test medium with a nominal concentration of 8.6 mg/L was prepared by completely diluting 55 mg of the working solution (corresponding to 42.8 mg water-free test substance) in 5.0 L of test water by intensive stirring at room temperature for 30 minutes in the dark. The test medium was prepared just before the introduction of the fish (i.e., start of the test and at the test medium renewal).
- Controls: test water

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: zebrafish
- Source: Breeding culture at the testing laboratory

- Length at study initiation(length definition, mean, range and SD): measured from the mouth to the end of the tail fin, 2.7 ± 0.1 cm
- Weight at study initiation (mean and range, SD): 0.12 ± 0.02 g
- Feeding during test: none

HOLDING AND ACCLIMATION
No medication was applied during holding and acclimatization.
- Acclimation period: ≥ 1 week
- Acclimation conditions (same as test or not): same
- Feeding during acclimation: until one day before the start of the test, the fish were fed with a commercial fish diet (Tetra Min® Hauptfutter, TETRA-Werke, 49324 Melle / Germany)
- Health during acclimation (any mortality observed): During the last four weeks prior to the test, no fish died in the test fish batch and all fish were healthy.

FEEDING DURING TEST
none

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

1.25 mM (125 mg CaCO3/L)

Test temperature:

22 °C

pH:

7.2 - 7.4

Dissolved oxygen:

≥ 8.2 mg/L (≥ 93 % oxygen saturation)

Nominal and measured concentrations:

nominal concentration: 8.6 mg/L (water-free)
measured concentrations:
freshly prepared test media: 114-116 % of nominal
aged test media (48 h): 119-123 % of nominal
The biological results are based on the mean measured concentration of 10.1 mg/L (calculated as arithmetic mean over all concentrations measured at the start and the end of the two test medium renewal periods).

Details on test conditions:

TEST SYSTEM
- Test vessel: full glass aquarium, containing five liters test medium
- Type (delete if not applicable): open
- Aeration: slight aeration
- Renewal rate of test solution (frequency/flow rate): after 48 hours
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.17 g fish wet weight/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: purified water
- Alkalinity: 0.4 mM
- Ca/Mg ratio: 4:1
- Culture medium different from test medium: no
- Intervals of water quality measurement: water temperature, pH and oxygen concentration were measured at the start of the test and once during the test in the freshly prepared and aged test medium. At the same dates the appearance of the test medium was recorded.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hour light to 8-hour dark photoperiod, with a 30-minute transition period
- Light intensity 15 – 16 µE s-1 m-2

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality and sub-lethal effects; recorded at approx. 3, 24, 48, 72 and 96 hours

TEST CONCENTRATIONS
- Results used to determine the conditions for the definitive study: A limit test based on the threshold approach was performed (OECD Series on testing and assessment No. 126 (2010): Short Guidance on the Threshold Approach for Acute Fish Toxicity). The selected concentration of nominal 8.6 mg/L water-free test item (mean measured 10.1 mg/L) was based on the EC50 values determined in an algae study (OECD 201, EC C.3) and an acute daphnia study (OECD 202, EC C.2). The lower EC50 value was determined in the algae test to be 3.0 mg/L, based on growth rate (EC50 for daphnia was >100 mg/L).

Reference substance (positive control):

not required

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 10.1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Remarks:

corrected for water content

Basis for effect:

mortality (fish)

Remarks on result:

other:

Remarks:

highest concentration tested in a threshold approach

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 10.1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Remarks:

corrected for water content

Basis for effect:

other: mortality and sub-lethal effects

Remarks on result:

other:

Remarks:

highest concentration tested in a threshold approach

Details on results:

- Behavioural abnormalities:
- Other biological observations: none; all fish survived and no visible abnormalities were observed.
- Mortality of control: none
- Other adverse effects control: none

The test medium was a clear solution throughout the test medium renewal periods of 48 hours.

Reported statistics and error estimates:

The NOEC and LC0 were determined directly from the raw data. The LOEC, LC100 and LC50 at the observation times could not be quantified due to the absence of a toxic effect of the test item at the tested threshold concentration.

Validity criteria fulfilled:

yes

Remarks:

/ mortality of control animals <10 %; concentration of dissolved oxygen in all test vessels >60 % saturation

Description of key information

96-h LC50 > 10 mg/L for Zebrafish (Danio rerio) (OECD 203, EU C.1; threshold approach)

Additional information

LC50 for freshwater fish: > 10 mg/L (threshold approach)