Oxydipropyl dibenzoate

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

December 2018 to May 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Oxydipropyl dibenzoate

EC Number:

248-258-5

EC Name:

Oxydipropyl dibenzoate

Cas Number:

27138-31-4

Molecular formula:

C20H22O5

IUPAC Name:

oxydipropyl dibenzoate

Details on test material:

- Name of test material (as cited in study report): Dipropylene glycol dibenzoate (DPGDB)
- Physical state: Clear colourless liquid
- Analytical purity: Not stated
- Lot/batch No.: 9903-28-1
- Expiration date of the lot/batch: 29 July 2000
- Storage condition of test material: Room temperature.

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Chemical marketing Concept, New Milford, Connecticut V988816101
- Expiration date of the lot/batch: 31 October 2019
- Purity test date:

RADIOLABELLING INFORMATION (if applicable)
- Radiochemical purity:
- Specific activity:
- Locations of the label:
- Expiration date of radiochemical substance:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material:
- Stability under test conditions:
- Solubility and stability of the test substance in the solvent/vehicle:
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium:

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing:
- Preliminary purification step (if any):
- Final dilution of a dissolved solid, stock liquid or gel:
- Final preparation of a solid:

FORM AS APPLIED IN THE TEST (if different from that of starting material)

TYPE OF BIOCIDE/PESTICIDE FORMULATION (if applicable)

OTHER SPECIFICS:
- measurement of pH, osmolality, and precipitate in the culture medium to which the test chemical is added:
- other information:

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Days 0, 7, 14 adn 20 (new) - each treatment level and the control prior to division into replicate vessels
Dsya 1, 8, 15 and 21 (aged) - composite of all available replicate vessels within each treatment level and the control
The number of samples taken from each exposure solution was one at each interval.

Test solutions

Vehicle:

no

Details on test solutions:

The test substance was added directly to full volume of dilution water and was observed to be clear and colorless with oily globules of undissolved test substance on the surface. The solution was mixed slowly overnight using a Teflon-covered stir bar and magnetic stir plate. Following mixing overnight, the solution was observed to be clear and colorless with oily globules of undissolved test substance on the surface. The solubilized portion of the solution was carefully drained into a glass beaker from a spout on the bottom of the bottle, avoiding the surface of the solution. The resulting 100% of a 100 mg/L WAF solution was observed to be clear and colorless with no visible undissolved test substance following preparation. Based on stability information obtained during the trial, which determined that the stock was stable for up to 24 hours, the primary stock was prepared daily in the same manner as described above.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone:
- Justification for species other than prescribed by test guideline:
- Age at study initiation (mean and range, SD): <24 hrs
- Weight at study initiation (mean and range, SD):
- Length at study initiation (length definition, mean, range and SD):
- Stage and instar at study initiation:
- Valve height at study initiation, for shell deposition study (mean and range, SD):
- Peripheral shell growth removed prior to test initiation:
- Method of breeding:
- Source: Smithers Viscient
- Age of parental stock (mean and range, SD):
- Feeding during test none
- Food type:
- Amount:
- Frequency:

ACCLIMATION
- Acclimation period:
- Acclimation conditions (same as test or not):
- Type and amount of food:
- Feeding frequency:
- Health during acclimation (any mortality observed):

QUARANTINE (wild caught)
- Duration:
- Health/mortality:

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES, INCLUDING CULTURING CONDITIONS:

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Remarks on exposure duration:

21-day reproduction study

Post exposure observation period:

None

Test conditions

Hardness:

170 to 180 CaCO3 (mg/L)

Test temperature:

19 to 21 °C

pH:

7.5 to 8.3

Dissolved oxygen:

7.4 to 10

Salinity:

NA

Conductivity:

740 to 790

Nominal and measured concentrations:

0 (control), 2.6, 6.4, 16, 40 and 100 mg/L (as % of 100 mg/L WAF) nominal and control, 0.12, 0.33, 0.83, 2.2 and 5.6 mg/L geometric mean measured concentration

Details on test conditions:

TEST SYSTEM
- Test vessel: 100-mL clear glass beakers
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 80 mL
- Aeration: none
- Type of flow-through (e.g. peristaltic or proportional diluter): NA
- Renewal rate of test solution (frequency/flow rate):
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates):10
- No. of vessels per control (replicates): 10
- No. of vessels per vehicle control (replicates): NA
- Biomass loading rate:

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Fortified laboratory well water
- Total organic carbon:
- Particulate matter:
- Metals:
- Pesticides:
- Chlorine:
- Alkalinity:
- Ca/mg ratio:
- Conductivity:
- Culture medium different from test medium:
- Intervals of water quality measurement:

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

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :

TEST CONCENTRATIONS
- Spacing factor for test concentrations:
- Justification for using less concentrations than requested by guideline:
- Range finding study: 17-day preliminary range-finding exposure
- Test concentrations: control, 0.10, 1.0, 10 and 100 as % of 100 mg/L WAF
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

5.6 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Effect concentrations 2

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

2.2 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

reproduction

Effect concentrations 3

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

2.2 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

other: length

Details on results:

- Behavioural abnormalities:
- Observations on body length and weight: yes
- Other biological observations:
- Mortality of control: 10%
- Other adverse effects control:
- Immobilisation of control:
- Abnormal responses:
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values:
- Effect concentrations exceeding solubility of substance in test medium:

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Based on nominal concentrations and the most sensitive endpoints, reproduction (total living offspring per surviving female) and length, the 21-day No-Observed-Effect Concentration (NOEC) and Lowest-Observed-Effect Concentration (LOEC) were determined to be 40 and 100% of 100 mg/L WAF, respectively (2.2 and 5.6 mg/L as geometric mean measured concentrations, respectively).

Executive summary:

The objective of this study was to evaluate the chronic effects of Benzoflex 9-88 on the survival, reproduction, and growth (mean total body length) of the daphnid, Daphnia magna.  The exposure was performed under static-renewal conditions for a period of 21 days.  Results of this study were used to determine the No-Observed-Effect Concentration (NOEC) and Lowest-Observed-Effect Concentration (LOEC) for the most sensitive biological parameter monitored (e.g., daphnid survival, reproduction, and total body length).  In addition, a median effective concentration (EC50), EC20, and EC10 values for survival, reproduction, and growth (total body length) were determined.  The results of this study are based on nominal and geometric mean measured concentrations of Benzoflex 9-88.