E17-194T, (P,P-diethyl, monoester with 1,2 propanediol)_

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:

February 21, 2018 - April 19, 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)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material:
2242-62-5
- Expiration date of the lot/batch:
November 3, 2020
- Purity test date:85.3%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material:
ambient conditions.

Analytical monitoring:

yes

Details on sampling:

- Sampling method: Test water samples were collected from the batches of test solution prepared for each treatment and control group at the beginning of the test, and from two of the four replicate test chambers in each treatment and control group at 48 hours (± 1 hour) to measure concentrations of the test substance. Samples (8.0 mL) were collected from mid-depth, placed in glass vials containing 2.0 mL of 0.5% formic acid in methanol and processed immediately for analysis.

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: The cladoceran, Daphnia magna, was selected as the test species for this study.
- Strain/clone:
- Justification for species other than prescribed by test guideline:
- Source: neonates obtained from cultures maintained by EAG Laboratories in Easton, Maryland.
- Age of parental stock (mean and range, SD): Daphnids used in the test were <24-hour old
- Feeding during test: The adults were fed during the 24-hour period prior to test initiation, but neonates were not fed during the test.
- Food type: mixture of yeast, cereal grass media and trout chow (YCT), supplemented with a vitamin stock solution and a suspension of the freshwater green alga, Raphidocelis subcapitata.
- Amount:
- Frequency:Daphnids in the cultures were fed daily

ACCLIMATION
- Acclimation period:Adult daphnids were cultured in water from the same source and at approximately the same temperature as used during the test. During the 2-week period immediately preceding the test,
- Acclimation conditions (same as test or not):
- Type and amount of food: mixture of yeast, cereal grass media and trout chow (YCT), supplemented with a vitamin stock solution and a suspension of the freshwater green alga, Raphidocelis subcapitata.
- Feeding frequency: Daphnids in the cultures were fed daily
- Health during acclimation (any mortality observed): The four adult daphnids used to supply neonates for the test were held for 14 days prior to collection of the juveniles for testing, and had each produced at least two previous broods. Adult daphnids in the culture had produced an average of at least three young per adult per day over the 7-day period prior to the test. The adults showed no signs of disease or stress, no ephippia were produced during the holding period, and mortality in the culture stock was 0% in the two-day period prior to test initiation

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

Observations of immobility and other signs of toxicity were made approximately 3, 24 and 48 hours after test initiation

Hardness:

128 mg/L as CaCO3

Test temperature:

Temperature Range: 19.0 – 20.3°C

pH:

pH Range: 8.1 – 8.5

Dissolved oxygen:

Dissolved Oxygen Concentration: ≥90% ASV; no aeration

Salinity:

Alkalinity 178 mg/L as CaCO3

Conductivity:

312 μS/cm

Nominal and measured concentrations:

TEST CONCENTRATIONS: Nominal Mean Measured
Negative Control < LOQ
6.3 mg a.i./L 6.4 mg a.i./L
13 mg a.i./L 13 mg a.i./L
25 mg a.i./L 24 mg a.i./L
50 mg a.i./L 50 mg a.i./L
100 mg a.i./L 102 mg a.i./L

Details on test conditions:

TEST SYSTEM
- Test vessel: chambers
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: not specify
- Aeration: no aeration
- No. of organisms per vessel:five daphnids in each test chamber
- No. of vessels per concentration (replicates):Four replicate test chambers were maintained in each treatment group
- No. of vessels per control (replicates):Four replicate test chambers were maintained in control group
- No. of vessels per vehicle control (replicates): no
- Biomass loading rate:Loading in each test chamber during the test was approximately 40 mL of test solution per daphnid.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:freshwater obtained from a well approximately 40 meters deep located on the EAG Laboratories site in Easton, Maryland. The well water was passed through a sand filter to remove particles greater than approximately 25 m, and pumped into a 37,800-L storage tank where the water was aerated with spray nozzles. Prior to use in the test system, the water was filtered to 0.45 m to remove fine particles and was passed through an ultraviolet (UV) sterilizer.
- Total organic carbon:<1mg C/L
- Particulate matter:
- Metals:Analysis table is provided in the background material
- Pesticides:Analysis table is provided in the background material
- Chlorine:Analysis table is provided in the background material
- Alkalinity: 187 mg/L as CaCO3
- Ca/mg ratio:Analysis table is provided in the background material
- Conductivity: 332-350 μS/cm
- Salinity:Analysis table is provided in the background material
- Intervals of water quality measurement: periodically.

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod:16 hours of light
and 8 hours of darkness. A 30-minute transition period of low light intensity was provided when lights went on and off to avoid sudden changes in light intensity.
- Light intensity:559 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :

VEHICLE CONTROL PERFORMED: no

RANGE-FINDING STUDY
- Test concentrations: The range-finding study was conducted at nominal concentrations of 0.16, 0.80, 4.0, 20 and 100 mg/L for 48 hours under static test conditions.
- Results used to determine the conditions for the definitive study: Percent immobility in the 0.16, 0.80, 4.0, 20 and 100 mg/L treatment groups at test termination was 0, 0, 0, 0 and 0%, respectively.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

Percent immobility in the 6.3, 13, 25, 50 and 100 mg a.i./L treatment groups at test termination was 0, 0, 0, 0 and 0%, respectively. Signs of toxicity observed among the surviving daphnids in the 100 mg a.i./L treatment group at test termination included lethargy.

Validity criteria fulfilled:

yes

Conclusions:

The cladoceran, Daphnia magna, was exposed for 48 hours under static conditions to five nominal concentrations of E17-194T ranging from 6.3 to 100 mg a.i./L. Based on the nominal
concentrations, the 48-hour EC50 value was >100 mg a.i./L, the highest concentration tested. The 48-hour no-immobility concentration and the NOEC were both 100 mg a.i./L.

Executive summary:

The cladoceran, Daphnia magna, was exposed for 48 hours under static conditions to five nominal concentrations of E17-194T ranging from 6.3 to 100 mg a.i./L. Based on the nominal concentrations, the 48-hour EC50 value was >100 mg a.i./L, the highest concentration tested. The 48-hour no-immobility concentration and the NOEC were both 100 mg a.i./L.

Description of key information

The cladoceran, Daphnia magna, was exposed for 48 hours under static conditions to five nominal concentrations of E17-194T ranging from 6.3 to 100 mg a.i./L. Based on the nominal concentrations, the 48-hour EC50 value was >100 mg a.i./L, the highest concentration tested. The 48-hour no-immobility concentration and the NOEC were both 100 mg a.i./L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

100 mg/L