Decyl dihydrogen phosphate, potassium salt

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Good quality study under GLP, however no chemical analyses.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

no chemical analyses

GLP compliance:

yes

Analytical monitoring:

no

Details on sampling:

no chemical analyses

Details on test solutions:

Direct dispersion in water. 1.0 g of test material was dispersed in 1 litre of diluent to give a stock solution of
1000 mg/l from which serial dilutions were made to give the test series.
The test material was suspected to absorb to glassware and so saturation of the absorption sites was achieved by soaking
the test vessels overnight prior to the start of the test with the test solutions.

Test organisms (species):

Daphnia magna

Details on test organisms:

Laboratory culture originating from a strain supplied by the Institut National de Recherche Chimique Appliquke, (I.R.CH.A), France. Cultures were fed
daily with a suspension of mixed algae (predominantly Chlorell a spp.) . Culture conditions ensure that reproduction is by parthenogenesis.
Gravid adults were isolated 24 hours prior to initiation of the test. Young daphnids produced overnight- were used for testing.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

no

Hardness:

Approximately 50 mg/L as CaCO3

Test temperature:

22 ºC

pH:

7.2-7.6

Dissolved oxygen:

8.4 - 8.5 mgO2/L

Nominal and measured concentrations:

nominal concentrations:0, 3.2, 5.6, 10, 18, 32, 56, 100, 180 and 320 mg/l

Details on test conditions:

Test vessels: glass jars each containing 200 ml test solution and covered to reduce evaporation
Experimental design: 9 test concentrations plus 1 control, each in duplicate. 20 animals per concentration.
Method of initiation: Daphnia's were placed in the test solution after addition of the test material.
Loading: 20 ml test solution per organism
Photoperiod: 16h light 8h dark
Temperature: 22ºC
Aeration: none
Test concentrations: 3.2, 5.6, 10, 18, 32, 56, 100, 180 and 320 mg/l
Mediurn renewal: none
Duration o f exposure :48 hours
Criteria of effect: Daphnia were considered to be immobilised if they were unable to swim for approximately 15 seconds after gentle agitation.

Reference substance (positive control):

no

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

38 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CL (32-44 mg/L)

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

18 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

15.2 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mobility

Results with reference substance (positive control):

no

Concentration (mg/L)	Cumulative immobilized Daphnia (initial population : 10 per concentration)
	24 hours				48 hours
	R1	R2	Total	%	R1	R2	Total	%
3.2	0	0	0	0	0	0	0	0
5.6	0	0	0	0	0	0	0	0
10	0	0	0	0	0	0	0	0
18	0	0	0	0	0	0	0	0
32	0	0	0	0	3	4	7	35
56	2	4	6	30	9	8	17	85
100	8	7	15	75	10	10	20	100
180	10	10	20	100	10	10	20	100
320	10	10	20	100	10	10	20	100

R1 and R2 = replicate 1 and 2

Validity criteria fulfilled:

yes

Conclusions:

Good quality study, however no chemical analyses therefore concentrations nominal.

Executive summary:

TEST SPECIES: Daphnia Magna Straus

TEST TYPE: Acute toxicity 48h EC50 (immobilisation)

TEST CONDITIONS: static test conditions according to OECD Guideline No. 202 Part 1 referenced as Method C. 2 of Commission Directive 84/449/EEC (which constitutes Annex V of Council Directive 67/584/EEC)

RESULTS:

EC50 (48h) 38 mg/L 15.2 mg/L ai

ai = active ingredient "No Observed Effect Concentration" (NOEC) 18mg/l (7.2 mg ai / l )

Description of key information

In a study according to OECD Guideline No. 202 Part 1 referenced as Method C. 2 of Commission Directive 84/449/EEC (which constitutes Annex V of Council Directive 67/584/EEC) the EC50 (48h) 38 mg/L (15.2) mg/L ai was determined.