Isodecyl diphenyl phosphate

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

Study period:

48 hours

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Purity: >90%
Batch: 900150909STG115

Analytical monitoring:

yes

Details on sampling:

Chemical analysis of the test item was carried out at 0 and 48 hours.

Vehicle:

yes

Remarks:

dimethylformamide

Details on test solutions:

A nominal amount of test item (100 mg) was dissolved in dimethylformamide and the volume adjusted to 10 mL to give a 100 mg/10 mL solvent stock solution. An aliquot (500 μL) of this 100 mg/10 mL solvent stock solution was dispersed in 5 liters of deionized reverse osmosis water with the aid of magnetic stirring for approximately 30 minutes to give the required test concentration of 1.0 mg/L. After stirring any undissolved test item was removed by centrifugation at 10000 g for 30 minutes to give a 100% v/v solution of the test item.

Test organisms (species):

Daphnia magna

Details on test organisms:

1st instar Daphnia magna derived from in-house laboratory cultures

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Hardness:

The reconstituted water had an approximate theoretical total hardness of 250 mg/L as CaCO3

Test temperature:

21-22 deg C

pH:

7.8 +/- 0.2

Dissolved oxygen:

8.7-9 mg O2/L

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.042 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Nominal Concentration (% v/v)	Observations (Initial Population: 10 Per Replicate)
	24 Hours		48 Hours
	Cumulative Immobilized Daphnia	Observations	Cumulative Immobilized Daphnia	Observations
Control	0	10 N	0	10 N
Solvent Control	0	10 N	0	10 N
0.10	0	10 N	0	10 N
1.0	0	10 N	0	10 N
10	0	10 N	0	10 N
100	0	10 N	7	3 N

Validity criteria fulfilled:

yes

Conclusions:

Exposure of Daphnia magna to the test item was investigated and gave the following result, EC50 0.042 mg/L.

Executive summary:

The substance was tested following the methods outline in the OECD 202 guideline. The test was conducted to GLP standards and fulfilled the validity criteria. The exposure of Daphnia magna to the test item gave an EC50 of 0.042 mg/L. As this result is above the water solubility of the substance, the substance is not considered toxic.

Description of key information

A 48h-EC50 of 0.042 mg/L was determined following the OECD 202 guidelines. This result is above the water solubility therefore the substance is not classified as acutely toxic. 

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.042 mg/L

Additional information

The available studies on the short-term toxicity of IDDPP towards aquatic invertebrates are listed in the table below:

 

Guideline	Test species	Endpoint	Result	Remarks
EPA-660/3-75-009	Daphnia magna	48h-EC50	0.34 mg/l (nominal) Pydraul 312C	Supporting study, rel. 2
US EPA, 1975. Methods for acute toxicity tests with fish, macroinvertebrates and amphibians.	Chironomus tentans	48h-EC50	0.61 mg/l (nominal) Santicizer 148	Supporting study, rel. 2
US EPA, 1975. Methods for acute toxicity tests with fish, macroinvertebrates and amphibians.	Paratanytarsus parthenogenetica	48h-EC50	1.32 mg/l (nominal) Santicizer 148	Supporting study, rel. 2
		48h-EC50		Supporting study, rel. 3
Daphnia sp., 48 -hour Acute Immobilization test OECD 202, Envigo 2016	Daphnia magna	48h-EC50	0.042 mg/L (geomean measured)	Key Study, GLP, rel. 1

As all measured toxicity values are well above the water solubility (11.2 ug/l) of the substance, IDDPP can not be classified as toxic to the environment.