3,5-diethyl-1,2-dihydro-1-phenyl-2-propylpyridine

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:

29 January 2018 to 08 April 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

The test item is listed as PDHP (CAS # 34562-31-7), a yellow to amber colored liquid obtained from the Sponsor, Vertellus, with > 85% purity and stored at room temperature in the dark.

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

The test was carried out using first instar Daphnia magna derived from in-house laboratory cultures.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

20°C to 22 °C

pH:

7.8 to 8.0

Dissolved oxygen:

8.4 to 9.4 mg O2/L

Nominal and measured concentrations:

Based on the results of the range-finding test, the definitive test was conducted with an aqueous solution of the test item at nominal concentrations of 6.25, 12.5, 25, 50 and 100% v/v saturated solution. The 100% v/v saturated solution corresponds to an initial loading rate of 50 mg/L.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate was used as the reference item at concentrations of 0.32, 0.56, 1.0, 1.8 and 3.2 mg/L.

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

43 other: % v/v saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other:

Remarks:

Statistically-derived value corresponding to a 43% v/v saturated solution prepared from a dilution of an initial test solution with an initial loading rate of 50 mg/L.

Key result

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other:

Remarks:

Statistically-derived value corresponding to a test solution prepared as a dilution of an initial test solution with an initial loading rate of 50 mg/L, resulting in a 43% v/v saturation solution.

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

25 other: % v/v saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other:

Remarks:

Statistically-derived value corresponding to a test solution prepared as a dilution of an initial test solution with an initial loading rate of 50 mg/L, resulting in a 43% v/v saturation solution.

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

12.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other:

Remarks:

Test solution prepared as a dilution of an initial test solution with an initial loading rate of 50 mg/L, resulting in a 25% v/v saturation solution.

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

50 other: % v/v saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other:

Remarks:

50% v/v saturated solution prepared from a dilution of an initial test solution with an initial loading rate of 50 mg/L.

Duration:

48 h

Dose descriptor:

LOELR

Effect conc.:

25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other:

Remarks:

Test solution prepared as a dilution of an initial solution with an initial loading rate of 50 mg/L, resulting in a 100% v/v saturation solution.

Results with reference substance (positive control):

The results from the positive control with potassium dichromate were within the normal range for this reference item.

Validity criteria fulfilled:

yes

Remarks:

The test was considered valid since none of the control daphnids showed immobilisation or other signs of disease or stress and the oxygen concentration at the end of the test was equal to or greater than 3 mg/L in the control and test vessels.

Conclusions:

Acute immobilisation of Daphnia magna resulted from a 48-h exposure to a series of substance concentrations, each prepared from an initial 100% v/v saturated solution with an initial loading rate of 50 mg/L. The test concentrations included the 100% v/v saturated solution and a series of dilutions containing 6.25, 12.5, 25, and 50% v/v saturated solution. The effects concentrations were reported both as 48-h EC50 = 43% v/v saturated solution and 48-h EL50 =22 mg/L. The no effects concentrations were reported both as 48-h NOEC of 25% v/v saturated solution and 48-h NOELR of 12.5 mg/L.

Description of key information

The key study was a static acute invertebrate toxicity test on the effects of the substance on the freshwater invertebrate Daphnia magna following OECD Guideline 202. Acute immobilisation of Daphnia magna resulted from a 48-h exposure to a series of substance concentrations, each prepared from an initial 100% v/v saturated solution with an initial loading rate of 50 mg/L. The test concentrations included the 100% v/v saturated solution and a series ofdilutions containing 6.25, 12.5, 25, and 50% v/v saturated solution.  The effects concentrations were reported both as 48-h EC50 = 43% v/v saturated solution and 48-h EL50 = 22 mg/L.  The no effects concentrations were reported both as 48-h NOEC of 25% v/v saturated solution and 48-h NOELR of 12.5 mg/L. 

 

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

22 mg/L