Diphosphoric acid, compound with 1,3,5-triazine-2,4,6-triamine

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:

4-8 April 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study conducted in accordance with an internationally recognised method

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: it was decided that the definitive study be conducted as a limit test with test concentrations of 0 (Control) and 100mg/l only. A stock solution of 1000 mg/1 was prepared and stirred to mix. Appropriate volumes of the stock solution were then made up to 10 litres by addition of dechlorinated tap water to achieve the desired concentration. The test solutions were stirred to mix.

- Sampling method: samples of the test solutions in which the fish were exposed were taken for analytical verification at the start of the definitive study, before and after renewal of solutions at 24, 48, 72 hours, and at the end of the 96 hour exposure period.

- Sample storage conditions before analysis: test substance specific analysis of each test concentration was carried out as soon as possible after sampling.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: when the study was conducted using dechlorinated tap water as the dilution water analysis of the test solution indicated that only 7% of the nominal concentration could be recovered. The study was at the same test concentration of 0 (Control) and 100mg/1 using bottled natural spring water as the dilution water. A stock solution of 1000 mg/1 was prepared and stirred to mix. Appropriate volumes of the stock solution were then made up to 10 litres by addition of bottled natural spring water to achieve the desired concentration. The test solutions were stirred to mix

- Controls: as for test solution but without addition of test substance
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): not applicable, none used
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): 1000mg/L stock. 100mg/L test solution.
- Evidence of undissolved material (e.g. precipitate, surface film, etc): all test solutions were slightly cloudy white solutions when prepared using dechlorinated tap water but were clear colourless solutions when prepared using natural bottled spring water.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout
- Source: reputable supplier
- Age at study initiation (mean and range, SD):
- Length at study completion: 55.5 mm (mean of 10 fish measured)
- Weight at study completion: 1.53g (mean of 10 fish weighed)


ACCLIMATION
- Acclimation period: 5 days
- Acclimation conditions): same as test
- Health during acclimation (any mortality observed): 6.67% mortality

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

Declorinated tap water: 240 mg CaCO3/L
Bottle Spring water: 34 mg CaCO3/L

Test temperature:

15 ± 2°C

pH:

Control: 7.2 - 8.0
Test: 5.2 - 6.7

Dissolved oxygen:

Control: 98-100 air saturated value
Test: 98-100 air saturated value

Salinity:

Not applicable - freshwater study

Nominal and measured concentrations:

Analytical measurement of the exposure solutions showed the mean measured concentrations were not within 20% of the nominal concentrations. Therefore in accordance with OECD Guidelines, the measured concentrations should be used in the determination of the LC50, LOEC and NOEC values.

Details on test conditions:

TEST SYSTEM
- Test vessel: 12 litre volume aquaria
- Renewal rate of test solution): every 24 hours
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: dechlorinated tap water and bottled natural spring water

OTHER TEST CONDITIONS
- Adjustment of pH: none
- Photoperiod: 16 hours light and 8 hours dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Observations and records of mortalities were made every 24 hours, as close to test initiation time as possible

TEST CONCENTRATIONS
- Spacing factor for test concentrations: not applicable (limit test)
- Justification for using less concentrations than requested by guideline: see range finding results below
- Range finding study: yes
- Test concentrations:0.1, 1.0, 10, 100mg/L
- Results used to determine the conditions for the definitive study: no abnormalities or mortalities observed up to and including 100mg/L (three fish per concentration)

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 74.96 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities:
- Observations on body length and weight:
- Other biological observations:
- Mortality of control:
- Other adverse effects control:
- Abnormal responses:
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values:
- Effect concentrations exceeding solubility of substance in test medium:

Results with reference substance (positive control):

LC50: 154 mg/L (confidence limits 128-185)
NOEC (96 hrs): 60 mg/L
100% mortality (96 hrs): 240 mg/L

Sublethal observations / clinical signs:

No abnormalities or mortalities were observed in the range finding study nor in a definitive study conducted using bottle spring water.

An initial study using dechlorinated tap water as the dilution water was conducted, the result of this study was no mortalities or abnormal behaviour recorded from any of the exposed Rainbow trout. Due to the poor solubility of MPP in dechlorinated tap water the test was repeated using bottled natural spring water as the dilution water.

Validity criteria fulfilled:

no

Remarks:

Analytical measurement of the exposure solutions showed the mean measured concentrations were not within 20% of the nominal concentrations.

Conclusions:

No abnormality or mortality was observed in any fish exposed to 100mg/L nominal concentration of test substance (>74.96% measured concentration).

Description of key information

The 96 hour EC50 for fish was estimated to be >74.96 mg/L based on measured concentration and >100mg/l based upon nominal concentrations.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

74.96 mg/L

Additional information

In an acute toxicity study with rainbow trout, MPP was initially tested using dechlorinated tap water, but due to poor water solubility in this medium, the test was repeated using bottled natural spring water as the dilution water. No abnormalities or mortalities were observed in the range finding study nor in the definitive study conducted using bottle spring water at 100mg/L nominal concentration of test substance (>74.96% measured concentration).