2-isobutyl-4-methyltetrahydro-2H-pyran-4-yl acetate

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: GLP study according to OECD guideline

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2-isobutyl-4-methyltetrahydro-2H-pyran-4-yl acetate

EC Number:

942-380-9

Cas Number:

131796-64-0

Molecular formula:

C12H22O3

IUPAC Name:

2-isobutyl-4-methyltetrahydro-2H-pyran-4-yl acetate

Details on test material:

- Name of test material (as cited in study report): pyranyl acetate pure
- Physical state: Colourless to yellowish, clear, liquid
- Analytical purity: 99.0 corrected area-%
- Lot/batch No.: ZH 146
- Expiration date of the lot/batch: December 2015
- Stability under test conditions: Hydrolysis half-lives: 1088.7 h (pH 4, 50 °C),
5800.9 h (pH 9, 20 °C) (BASF study no 15L00024)
- Storage condition of test material: Ambient (room temperature)

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Sampling method: At the start of the exposure (0 hours), sampling was carried out after preparation of all test item concentrations. At the end of the exposure (48 hours), samples were taken directly from the test vessels containing daphnids. At the start of the exposure (0 hours), sampling was carried out after preparation of all test item concentrations. At the end of the exposure (48 hours), samples were taken directly
from the test vessels containing daphnids.

- Sample storage conditions before analysis: All samples were stored at room temperature until sample preparation and in an autosampler until the start of the analysis, if necessary.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)

A stock solution of 100 mg/L of the test item was freshly prepared with dilution water before the start of the exposure (at 0 hours) and stirred with a magnetic stirrer at approximately 1100 rpm for 2 hours at room temperature. The clear stock solution was used as
highest test concentration and for preparation of the further test concentrations. All tested concentration levels were visually clear throughout the exposure period.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna STRAUS (Clone 5).
- Source: lnstitut tor Wasser-, Boden- und Lufthygiene (WaBolu), 14195 Berlin, Germany
- Breeder: DR. U. NOACK-LABORATORIEN, Kathe-Paulus-Str. 1, 31157 Sarstedt, Germany
- Age at study initiation (mean and range, SD): 2 to 24 hours old daphnids from a healthy stock were used for the study. Juvenile daphnids were removed from the culture vessels latest 22 hours before the start of the exposure and discarded. The juveniles born within this period of max. 22 hours preceding the exposure were used for the test after additional 2 hours after collection. No first brood progeny was used for the test.
- Method of breeding: - Method of breeding: Culture: In glass vessels (2 - 3 L capacity) with approximately 1.8 L culture medium, at 20 ± 2°C, in an incubator, 16 h illumination; light intensity of max. 20 μE·m-2 . s-1
- Culture medium: Elendt M4, according to ELENDT (1990), modified to a total hardness of 160 to 180 mg CaCO3/l, was used.
- Culture feeding: The culture daphnids were fed at least 5 times per week ad libitum with a mix of unicellular green algae, e.g. Pseudokirchneriella subcapitata and Desmodesmus subspicatus, with an algae cell density of > 106 cells/ml. The algae were cultured at the test facility.
- Feeding during test: The daphnids were not fed during the study.

ACCLIMATION
- Acclimation period: Acclimatisation was not necessary, because the dilution water and environmental conditions were equivalent to the culture.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

160 to 180 mg CaC03/L

Test temperature:

18 - 22°c, constant within ± 1°C

pH:

7.67 - 8.19

Dissolved oxygen:

6.86 - 8.80

Nominal and measured concentrations:

Nominal concentrations: control, 3.13, 6.25, 12.5, 25.0, 50.0, 100 mg/L
Geometric mean measured concentrations: control, 0.715, 2.01, 3.15, 6.87, 23.8, 59.3 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:Glass beakers (4 (ID) x 7 (H) cm), 50 ml capacity, loosely covered
with watch glasses
- Test volume: 20 mL
- Renewal rate of test solution (frequency/flow rate):
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates):4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt M4, according to ELENDT (1990), modified to a total hardness of
160 to 180 mg CaC03/L, was used.

OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod: 16/8 h light/dark cycle
- Light intensity: Diffuse light, light intensity of max. 20 μE-m-2. s-1 (1340 Ix)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Test concentrations: The nominal test item concentrations mentioned above were based on
the results of a non GlP preliminary range finding test

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

15.4 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: < 0.715 - 18.7

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

22.3 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 19.8 - 25.1

Effect concentrations 3

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

59.3 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

The measured test item concentrations did not remain within ± 20 % of the nominal concentrations
throughout the exposure period. Therefore, the effect levels based on the
geometric mean measured concentrations of the test item pyranyl acetate pure.

Results with reference substance (positive control):

The percentage immobility for the reference item was determined after 24 hours. The EC50-value with
95 % confidence limits (Cl) was calculated by sigmoidal dose-response regression. The EC50-value
for the most recent of the monthly performed reference tests was: EC50: 2.00 mg/L (Cl 1.83 - 2.19 mg/L)

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Based on the geometric mean measured concentrations of the test item pyranyl acetate pure, the
48 hour-ECso for Daphnia magna was 22.3 mg/L (95 % confidence limits: 19.8 - 25.1 mg/L).