Sodium O,O-diethyl dithiophosphate

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:

2013.01.11 - 2013.08.06

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

ISO 7346-1 (Determination of the Acute Lethal Toxicity of Substances to a Freshwater Fish [Brachydanio rerio Hamilton-Buchanan (Teleostei, Cyprinidae)] - Part 2: Semi-static method)

GLP compliance:

yes (incl. QA statement)

Remarks:

(Not the chemical analyses)

Analytical monitoring:

yes

Details on sampling:

- Concentrations of the test product: (Nominal) 0; 125; 250; 500; 1,000 and 2,000 mg/L. The IBP1-Na (test substance) exist as 51% w/w active ingredient in the test product, considering this into calculation, the nominal concentration of IBP1-Na (test substance) is: 0; 63.8; 127.5; 255; 510 and 1020 mg/L.
- Sampling method: Samples were collected at test start, before and after renewal of the test solutions and at the end of the test for chemical analysis of the test product. Duplicate samples of 10 mL were collected in 20 mL plastic vials for later analysis. Only one of these samples were analysed and only those relevant for calculation of the LCx concentrations. The spare samples were discarded after sponsor approved the report.
- Sample storage conditions before analysis: at - 20 ˚C ± 2.0˚C

Vehicle:

no

Details on test solutions:

A stock solution of 2000 mg/l were prepared by weighing out 4000 mg of the test product and dissolving it in 2 l of zebra fish test medium. The test solution were prepared by diluting the stock solution in the zebra fish test medium. A fresh stock solution were prepared for renewal for the test solution after 48 hours.
The chemical analysis of IBP1-Na in samples collected during the test showed that the concentrations of IBP1-Na were 73-80% of the estimated nominal concentrations. As, on average, the measured concentrations of IBP1-Na in percentage of the estimated nominal concentrations were 78% and thus not within ± 20% of the estimated nominal IBP1-Na concentrations, the statistical calculation was made on the basis of the measured concentrations.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra fish
- Source: Credo Fish, Nørresundby, Denmark

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

22.4 ± 0.5 ˚C

pH:

7.7 ± 0.3

Dissolved oxygen:

94-100%

Nominal and measured concentrations:

See table below

Details on test conditions:

TEST SYSTEM
- Test vessel: aquarium
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: Glass, 4-L, 2 litres of test solution
- Renewal rate of test solution (frequency/flow rate): all test media were renewed after 48 hours.
- No. of organisms per vessel: 10

Reference substance (positive control):

yes

Remarks:

K2Cr2O7, CAS no 7778-50-9

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 791 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: nominal > 1020 mg/L; measured concentration >791 mg/L

Details on results:

- Behavioural abnormalities: None observed
- Behavioural abnormalities: None observed
- Mortality of control: None
- Other adverse effects control: None

Results with reference substance (positive control):

- Results with reference substance valid?
- Mortality: 7 at 200 mg/L, 10 at 300 mg/L, 10 at 400 mg/L
- LC50: 189 mg/L (48 hours)
- Other adverse effects: Swimming behavior, off balance

Sublethal observations / clinical signs:

Effect concentration obtained in acute toxicity tests with the test product, the active ingredient IBP1-Na. Time-weighted average measured concentrations given in bold and nominal concentration in parentheses.

	Concentration (mg/L)
	LC50 (24h)	LC50 (48h)	LC50 (72h)	LC50 (96h)
Test product	>1,551 (>2,000)	>1,551 (>2,000)	>1,551 (>2,000)	>1,551 (>2,000)
Active substance (IBP1-Na) 51% w/w in test product	>791 (>1,020)	>791 (>1,020)	>791 (>1,020)	>791 (>1,020)

Validity criteria fulfilled:

yes

Remarks:

The mortality in the controls <10% . The dissolved oxygen concentration > 60%. The average fish loading of 0.59 g/L met recommendation. Reference substance with LC50 189 mg/L is below normal 200-400 mg/L slightly higher sensitivity of fish.

Conclusions:

LC50(96h) for Danio rerio: greater than 791 mg/L(nominal 1,020 mg/L)
Remark: the test solution contains NaOH due to the production method.

Executive summary:

The short term toxicity to fish study was performed according to the OECD Guideline 203 and ISO 7346 -1 under GLP compliance. The test was done on zebra fish, they were exposed to the test material for 96hrs. As no mortality or any other significant effects were observed in even the highest exposed concentrations (nominal > 1020 mg/L; measured concentration >791 mg/L), the LC50(96) value of the active ingredient(IBP1-Na) was determined to be >791 mg/L.

Description of key information

Read-across, OECD 203, GLP compliance, LC50(96h) for Danio rerio: greater than 791 mg/L(nominal 1,020 mg/L)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

791 mg/L