Pidolic acid

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:

02 November 2016 to 29 Januray 2017

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)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot no. of test material: 20140124
- Expiration date of the lot/batch: 22 May 2019
- Purity test date: 22 May 2017

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Ambient temperature
- Stability under test conditions: No data

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Control, 6.25, 12.5, 25, 50 and 100 mg/L
- Sampling method: Four replicate samples (triplicate samples for analysis and 1 reserve sample) of freshly prepared test solutions at 0h and
- Sample storage conditions before analysis:

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 100 mg/L nominal test solution prepared in Elendt M4 medium. This test solution was used to prepare remaining test solutions by dilution
- Eluate: Elendt M4
- Controls: Test medium only
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): None
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): No data

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone: CEMAS laboratory culture
- Justification for species other than prescribed by test guideline: Not applicable
- Source: CEMAS laboratory
- Age of parental stock (mean and range, SD): No data
- Feeding during test: No
- Food type: Not applicable
- Amount: Not applicable
- Frequency: Not applicable

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES: Daphnia neonates were <24h old at the start of the test and were not 1st brood progeny

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

No data

Test temperature:

20 +/- 2oC

pH:

0h (new): 5.6 - 7.8
24h (aged): 6.8 - 7.7
24h (new): 5.7 - 7.9
48h (aged): 6.7 - 7.7

Dissolved oxygen:

0h (new): 9.37 - 9.63
24h (aged): 8.35 - 9.07
24h (new): 9.31 - 9.40
48h (aged): 8.24 - 9.04

Salinity:

No data

Conductivity:

No data

Nominal and measured concentrations:

Nominal test concentrations: Control and 6.25, 12.5, 25, 50 and 100 mg/L
Geometric mean measured test concentrations (48h): Control and 2.97, 9.13, 22.2, 46.9 and 94.1 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open (covered with Perspex sheet to allow air circulation)
- Material, size, headspace, fill volume: 100 mL glass beakers, filled with 60 mL test solution
- Aeration: None
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate):
- No. of organisms per vessel:
- No. of vessels per concentration (replicates):
- No. of vessels per control (replicates):
- No. of vessels per vehicle control (replicates):
- Biomass loading rate:

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
- Total organic carbon: No data
- Particulate matter: No data
- Metals: No data
- Pesticides: No data
- Chlorine: No data
- Alkalinity: No data
- Ca/mg ratio: No data
- Conductivity: No data
- Salinity: No data
- Intervals of water quality measurement:

OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod:
- Light intensity:

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :

VEHICLE CONTROL PERFORMED: yes/no

RANGE-FINDING STUDY
- Test concentrations:
- Results used to determine the conditions for the definitive study:

Reference substance (positive control):

yes

Remarks:

Separate study using ptoassium dichromate; 48h EC50 determined as 1.35 mg/L (95% CI 1.31 - 1.45 mg/L); result in line with published data for potassium dichromate

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

>= 94.14 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

>= 94.14 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

>= 94.14 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: None observed (compared to control)
- Mortality of control: <10% (0% observed)
- Other adverse effects control: None observed
- Abnormal responses: None observed
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: None observed

Immobilisation forDaphnia magna(initial population 20)
Nominal concn (mg/L)	Geometric mean measured concn (mg/L)	Observation period
		24-hour		48-hour
		Absolute no. immobilised	Cumulative no. immobilised	Absolute no. immobilised	Cumulative no. immobilised
Control (0)	-	0	0	0	0
6.25	2.97	0	0	0	0
12.5	9.13	0	0	0	0
25	22.2	0	0	0	0
50	46.9	0	0	0	0
100	94.1	0	0	0	0

Validity criteria fulfilled:

yes

Conclusions:

The 48-hour EC50 (immobility) was determined to be >94.1 mg/L under the conditions of the test

Executive summary:

In a 48-hour study the acute toxicity of the aquatic invertebrateDaphnia magnawas studied. The Daphnia were exposed to a range of test concentrations under semi-static conditions according to the OECD test guideline 202 and in compliance with GLP. The nominal test concentrations were a control and 6.25, 12.5, 25, 50 and 100 mg/L, with geometric mean measured test concentrations of 2.97, 9.13, 22.2, 46.9 and 94.1 mg/L, respectively.

No immobility was observed at any test concentration, therefore, the 48-hour EC50 (immobility) was determined to be >94.1 mg/L geometric mean measured concentration.

This acute toxicity study is considered acceptable and satisfied the guideline requirements for an aquatic invertebrate short-term toxicity test.

Description of key information

A reliable 48-hour study the acute toxicity of the aquatic invertebrateDaphnia magna was conducted. The Daphnia were exposed to a range of test concentrations under semi-static conditions according to the OECD test guideline 202 and in compliance with GLP.

No immobility was observed at any test concentration, therefore, the 48-hour EC50 (immobility) was determined to be >94.1 mg/L based on geometric mean measured concentrations.

This acute toxicity study is considered acceptable and satisfied the guideline requirements for an aquatic invertebrate short-term toxicity test

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

94.1 mg/L