Orthoperiodic acid

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 February 2013 to 26 February 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

A read-across justification report (RAAF) will be added to Section 13 as soon as possible.

Reason / purpose for cross-reference:

other: read-across target

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Sampling method: Water samples were taken from the control and the 0.20 % v/v saturated solution test vessel.
- Sampling method: Samples were taken at 0 and 72 hours (fresh media) and at 24 and 96 hours (old media) for quantitative analysis.
- Sample storage conditions before analysis: The samples were stored at approximately -20 °C prior to analysis. Duplicates of the samples detailed above, and samples at 24 (fresh media), 48 (old and fresh media) and 72 hours (old media) were taken and stored at approximately -20 °C for further analysis if necessary.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
An amount of test material (2250 mg) was added to 22.5 litres of dechlorinated tap water and dispersed with the aid of a propeller stirrer at a rate of approximately 1500 rpm for a period of 24 hours. After stirring, any undissolved test item was removed by filtration through a 0.2 μm Sartorius Sartopore filter (initial approximate 1 litre discarded to pre-condition the filter) to give the 100 % v/v saturated solution. An aliquot (40 mL) of this 100 % v/v saturated solution was added to a final volume of 20 litres of dechlorinated tap water to give the 0.20 % v/v saturated solution test concentration.
The test preparation was stirred using a flat-bladed mixer for approximately 1 minute to ensure adequate mixing and homogeneity.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout
- Source: Brow Well Fisheries Limited, Hebden, near Skipton, Yorkshire, UK
- Length at study termination (mean): 4.1 cm (sd = 0.3)
- Weight at study termination (mean):0.90 g (sd = 0.17)
- Feeding during test: no

ACCLIMATION
- Acclimation period: 12 days
- Acclimation conditions: same as test
- Type and amount of food: commercial trout pellets (feeding was discontinued approximately 24 hours prior to the start of the definitive test)
- Health during acclimation (any mortality observed): there was 1 mortality in the 7 days prior to the start of the test

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

140 mg/L as CaCO3

Test temperature:

13 - 14 °C

pH:

pH 7.7 - 8.2

Dissolved oxygen:

10.0 - 11.5 mg O2/L

Nominal and measured concentrations:

0.20 % v/v saturated solution (nominal) equivalent to 0.17 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 20 L glass exposure vessels
- Type : closed
- Aeration: yes (the test vessels were aerated via narrow bore glass tubes)
- Renewal rate of test solution (frequency): test solutions were renewed daily
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.32 g bw/L

TEST WATER
- Test water: Laboratory tap water was dechlorinated by passage through an activated carbon filter (Purite Series 500) and partly softened (Elga Nimbus 1248D Duplex Water Softener). After dechlorination and softening the water was passed through a series of computer controlled plate heat exchangers to achieve the required temperature.
- Water parameter measurements:
The water temperature, pH and dissolved oxygen concentrations were recorded daily throughout the test. The measurements at 0 hours, and after each test media renewal at 24, 48 and 72 hours, represent those of the freshly prepared test preparations while the measurements taken prior to each test media renewal, and on termination of the test after 96 hours, represent those of the used or 24-Hour old test preparations. The pH and oxygen were measured using a Hach HQ30d Flexi hand-held meter and the temperature was measured using a Hanna Instruments HI 93510 digital thermometer.

OTHER TEST CONDITIONS
- Photoperiod: 16 hours light and 8 hours darkness cycle with 20 minute dawn and dusk transition periods

EFFECT PARAMETERS MEASURED
Any mortalities and sub-lethal effects of exposure were recorded at 3, 6, 24, 48, 72 and 96 hours after the start of exposure. The criteria of death were taken to be the absence of both respiratory movement and response to physical stimulation.


TEST CONCENTRATIONS
In accordance with the recommendations of REACh, this test was conducted according to the threshold approach recommended by ECHA. Using this approach the lowest EC50 value from the Acute Toxicity to Daphnia magna study is set as the threshold concentration and a “Limit test” is conducted at this threshold concentration. If no mortalities were observed then this indicated that fish are not the most sensitive species and that the LC50 is greater than the threshold concentration. The results of the Acute Toxicity to Daphnia magna test (Harlan Study Number: 41204973) gave an EC50 value of 0.18 mg/L.
The study was therefore conducted at a single concentration of 0.20 % v/v saturated solution in order to gain a measured concentration of approximately 0.18 mg/L.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 0.17 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

0.17 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Mortality and Sub-lethal Effects: There were no mortalities in 7 fish exposed to a mean-measured test concentration of 0.17 mg/L for a period of 96 hours. Furthermore, there were no sub-lethal effects of exposure observed in the test.
- Observations on Test Material Solubility: The test preparation was observed to be a clear colourless solution for the duration of the test.
- Physico-Chemical Measurements: Temperature was maintained at 13 to 14 °C throughout the test, while there were no treatment related differences for oxygen concentration or pH.
The oxygen concentration in some of the test vessels was observed to have an air saturation value (ASV) in excess of 100 %. This was considered to be due to the presence of microscopic air bubbles in the media super-saturating the diluent and was considered not to have had an impact on the outcome or integrity of the test as no adverse effects were observed.

Sublethal observations / clinical signs:

Analytical Data

Analysis of the freshly prepared media at 0 and 72 hours showed measured concentrations of 0.15 and 0.19 mg/L respectively. Analysis of the old media at 24 and 72 hours showed measured concentrations of 0.15 and 0.18 mg/L. Due to the variability of the measured concentrations obtained, it was considered justifiable to base the results on mean-measured test concentrations.

Validity criteria fulfilled:

yes

Conclusions:

Based on the mean-measured test concentrations of the test media the acute toxicity of the test material to rainbow trout gave a 96-hour LC50 value of greater than 0.17 mg/L. The No Observed Effect Concentration was 0.17 mg/L.

Executive summary:

The acute toxicity of the test material to Oncorhynchus mykiss was investigated in a GLP study which was conducted in accordance with standardised guidelines OECD 203 and EU Method C.1.

In accordance with the recommendations of REACH, this test was conducted according to the threshold approach recommended by ECHA (2008). Using this approach the lowest EC50 value from the Acute Toxicity to Daphnia magna study is set as the threshold concentration and a “Limit test” is conducted at this threshold concentration. If no mortalities were observed then this indicated that fish are not the most sensitive species and that the LC50 is greater than the threshold concentration. The results of the Acute Toxicity to Daphnia magna test gave an EC50 value of 0.18 mg/L. Therefore the Acute Toxicity to Fish test was conducted at a single concentration of 0.20 % v/v saturated solution in order to gain a measured concentration of approximately 0.18 mg/L.

During the study, seven fish were exposed to an aqueous solution of the test material at a nominal concentration of 0.20 % v/v saturated solution for a period of 96 hours at a temperature of 13 to 14 °C under semi-static test conditions. The number of mortalities and any sub-lethal effects of exposure in each test and control vessel were determined 3 and 6 hours after the start of exposure and then daily throughout the test until termination after 96 hours.

Analysis of the freshly prepared media at 0 and 72 hours showed measured concentrations of 0.15 and 0.19 mg/L respectively. Analysis of the old media at 24 and 72 hours showed measured concentrations of 0.15 and 0.18 mg/L. Due to the variability of the measured concentrations obtained, it was considered justifiable to base the results on mean-measured test concentrations.

The 96-hour LC50 based on mean measured test concentrations was greater than 0.17 mg/L. The No Observed Effect Concentration was 0.17 mg/L.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted on read-across material

Justification for type of information:

A read-across justification report (RAAF) will be added to Section 13 as soon as possible.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 0.17 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

17 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Description of key information

Read-Across Substance:

The 96-hour LC50 based on mean measured test concentrations was greater than 0.17 mg/L. The No Observed Effect Concentration was 0.17 mg/L.

Additional information

Read-Across Substance:

The acute toxicity of the test material to Oncorhynchus mykiss was investigated in a GLP study which was conducted in accordance with standardised guidelines OECD 203 and EU Method C.1. The study was assigned a reliability score of 1 in accordance with the principles for assessing data quality as outlined in Klimisch et al (1997).

In accordance with the recommendations of REACH, this test was conducted according to the threshold approach recommended by ECHA (2008). Using this approach the lowest EC50 value from the Acute Toxicity to Daphnia magna study is set as the threshold concentration and a “Limit test” is conducted at this threshold concentration. If no mortalities were observed then this indicated that fish are not the most sensitive species and that the LC50 is greater than the threshold concentration. The results of the Acute Toxicity to Daphnia magna test gave an EC50 value of 0.18 mg/L. Therefore the Acute Toxicity to Fish test was conducted at a single concentration of 0.20 % v/v saturated solution in order to gain a measured concentration of approximately 0.18 mg/L.

During the study, seven fish were exposed to an aqueous solution of the test material at a nominal concentration of 0.20 % v/v saturated solution for a period of 96 hours at a temperature of 13 to 14 °C under semi-static test conditions. The number of mortalities and any sub-lethal effects of exposure in each test and control vessel were determined 3 and 6 hours after the start of exposure and then daily throughout the test until termination after 96 hours.

Analysis of the freshly prepared media at 0 and 72 hours showed measured concentrations of 0.15 and 0.19 mg/L respectively. Analysis of the old media at 24 and 72 hours showed measured concentrations of 0.15 and 0.18 mg/L. Due to the variability of the measured concentrations obtained, it was considered justifiable to base the results on mean-measured test concentrations.

The 96-hour LC50 based on mean measured test concentrations was greater than 0.17 mg/L. The No Observed Effect Concentration was 0.17 mg/L.