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Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline study conducted under GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2006
Report Date:
2006

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 850.1010 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)
Deviations:
no
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): PM-1265 (internal company product designation) and Cyclobutanediol, 2,2,4,4-Tetramethyl
- Substance type: production sample
- Physical state: solid
- Lot/batch No.: TS060505
- Storage condition of test material: ambient conditions

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
Samples were collected from the batches of test solution prepared at test initiation and frompooled solution from each replicate per treatment and control group at test termination to measure concentrations of the test substance. All samples were collected at mid-depth, placed in glass vials, and processed immediately for analysis.

Test solutions

Vehicle:
no
Details on test solutions:
A stock solution was prepared at a nominal concentration of 120 mg/L, the highest concentration tested, by mixing a calculated amount of PM-1265 into dilution water (UV sterilized well water). The stock solution was mixed by inversion and appeared clear and colorless. Aliquots of the 120 mg/L stock solution were proportionally diluted with well water to prepare 500 mL of test solution at nominal concentrations of 7.5, 15, 30 and 60 mg/L. The solutions were mixed by inversion. At test initiation and termination, all solutions appeared clear and colorless.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
Daphnid neonates used in the test were less than 24 hours old and were obtained from cultures maintained by Wildlife International, Ltd., Easton, Maryland. Adult daphnids were cultured in water from the same source and at approximately the same temperature as used during the test. Daphnids in the cultures were fed daily a mixture of yeast, cereal grass media and trout chow (YCT), as well as a suspension of the freshwater green alga, Pseudokirchneriella subcapitata. The adults were fed prior to test initiation, but neonates were not fed during the test. The 5 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 one previous brood. 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 and no ephippia were produced during the holding period. At test initiation, the juvenile daphnids were collected from the cultures and indiscriminately transferred one or two at a time to transfer chambers until each chamber contained 10 daphnids. Each group of daphnids then was transferred to an indiscriminately assigned test chamber. All transfers were made below the water surface using wide-bore pipettes.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h

Test conditions

Hardness:
140 mg/L as CaC03
Test temperature:
20 ± 1 °C
pH:
8.1 to 8.4
Dissolved oxygen:
≥ 8.1 mg/L (≥ 90% of saturation)
Nominal and measured concentrations:
Nominal concentrations selected for use in this study were 7.5, 15, 30, 60 and 120 mg/L.
Mean measured test concentrations for this study were 7.2, 13, 26, 50 and 106 mg/L
Details on test conditions:
Daphnids were exposed to a geometric series of five test concentrations and a negative control (dilution water) for 48 hours under static conditions. Two replicate test chambers were maintained in each treatment and control group, with 10 daphnids in each test chamber for a total of 20 daphnids per concentration.Test chambers were 250-mL glass beakers containing approximately 250 mL of test water. The depth of the test water in a representative chamber was 7.9 cm. Daphnids were impartially assigned to test chambers at test initiation. Observations of mortality, immobility and other signs of toxicity were made approximately 3, 24 and 48 hours after test initiation.

Results and discussion

Effect concentrationsopen allclose all
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 106 mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
48 h
Dose descriptor:
NOEC
Effect conc.:
>= 106 mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
test mat.
Basis for effect:
mobility

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Executive summary:

The cladoceran, Daphnia magna, was exposed for 48 hours under static conditions to five mean measured concentrations of PM-1265 ranging from 7.2 to 106 mg/L. No treatment-related effects were observed among daphnia at any concentration tested. The 48-hour EC50 value was > 106 mg/L, the highest concentration tested. The 48-hour no-mortality/immobility concentration and the NOEC were both 106 mg/L.