Reaction mass of 2-(1,1-dimethylethyl)-4-{[5-(1,1-dimethylethyl)-4-hydroxy-2-methylphenyl]thio}-5-methylphenyl 3-(dodecylthio)propionate and thiobis[2-(1,1-dimethylethyl)-5-methyl-4,1-phenylene] bis[3-(dodecylthio)propionate]

Bioaccumulation: aquatic / sediment

Administrative data

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE CATEGORY APPROACH


1. HYPOTHESIS FOR THE CATEGORY APPROACH (ENDPOINT LEVEL)
Please see full read across assessment justifcation document attached below titled "Adeka AO-26 Bioacc-RA assessment_2019-06-28_final.

2. CATEGORY APPROACH JUSTIFICATION (ENDPOINT LEVEL
Please see full read across assessment justifcation document attached below titled "Adeka AO-26 Bioacc-RA assessment_2019-06-28_final.

Cross-reference

Reason / purpose for cross-reference:

read-across source

Reference

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

18th April 2005 - 13th July 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 305 (Bioconcentration: Flow-through Fish Test)

Version / remarks:

The study was conducted in accordance with “Bioconcentration study for chemicals in body of fish”
prescribed in “Methods of Testing New Chemical Substances” (Yakushokuhatsu 1121002,Heisei
15-11-13 Seikyoku No. 2, Kanpokihatsu 031121002: Nov. 21, 2003) and OECD Test Guideline No.
305.

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Details on sampling:

- Sampling intervals/frequency for test organisms:
- Sampling intervals/frequency for test medium samples:
- Sample storage conditions before analysis:
- Details on sampling and analysis of test organisms and test media samples (e.g. sample preparation, analytical methods):

Vehicle:

yes

Remarks:

Test substance was weighed accurately and dissolved in acetonitrile.

Details on preparation of test solutions, spiked fish food or sediment:

Standard solution for determination of test substance concentration in analysis sample was prepared according to the following procedure:
0.1 g of test substance was weighed accurately and dissolved in acetonitrile to obtain concentration of 1000 mg/L (total value).
The solution was diluted serially with mixed solvent of Acetonitrile/H2O (80/20, v/v) to prepared diluted solutions of 0.200 and 7.00 mg/L (total value each) and was used for determining minimum detectable concentration and range of calibration curve.

Creating Calibration Curve
Above standard solution (1000 mg/L, total value) was serially diluted with Acetonitrile/H2O (80/20, v/v) to prepare solutions for creation of calibration curve with concentrations of 0.200, 1.00, 2.00, 4.00 and 7.00 mg/L (total value each). These solutions for creation of calibration curve were injected to HPLC based on the measurement condition which is descried in (1). Using obtained chromatogram, calibration curve was created based on peak area and concentration of the injected solution (total value and values for each peak).

Preparation Method of Stock Solution
Group 1: Test substance (4.0 g, purity corrected) and dispersant (HCO-40, 200 g) was mixed and dissolved into mixed solvent of Acetone/DMSO (10/90, v/v) to prepare 2.0 L of stock solution with test substance concentration of 2000 mg/L (total value).

Group 2: Test substance (0.40 g, purity corrected) and dispersant (HCO-40, 200 g) was mixed and dissolved into mixed solvent of Acetone/DMSO (10/90, v/v) to prepare 2.0 L of stock solution with test substance concentration of 200 mg/L (total value).

Control: Dispersant (HCO-40, 200 g) was dissolved into mixed solvent of Acetone/DMSO (10/90, v/v) to prepare 2.0 L of stock solution with no test substance.

Test organisms (species):

Cyprinus carpio

Details on test organisms:

Conduct of Bioconcentration Study
(1) Species: Common Carp (Cyprinus carpio)
(2) Supplier: Kitamura Fish Farm Gunchiku 12-388, Yatsushiro-shi, Kumamoto, Japan
(3) Lot Number: 050113c(1)
(4) Age: 1 year
(5) Breeding Condition: After abnormal fish was excluded at visual inspection upon releasing to medication bath (medication: Green F Gold,
conc.:27 mg/L, 2 days, temp.: 25oC), fish was held under static condition (w/ circulation filtering device) for 94 days.
(6) Acclimation Condition: After abnormal fish was excluded at visual inspection after breeding, required number of fish was transferred to acclimation bath.
Fish was treated to disinfectant, and then was held under flow-through condition for 23 days. Acclimation Completion: May 12th, 2005
(7) Total Length: Mean 8.9 cm (before exposure start)
(8) Body Weight: Mean 8.7 g (before exposure start) Minimum value was confirmed to be higher than 2/3 of maximum value.
(9) Feeding: Compound feed for carp (Nosan Corporation, crude protein:
>39.0%, crude fat: >3.0%) to which 5% w/w oil for aquaticulture (Riken Field Oil Omega, Riken Vitamin, Co., Ltd.) was added was fed 2 – 3 times a day at the quantity of approximately 1 -2% of individual body weight of test fish.Feeding was stopped from 10 hours before test initiation.
(10) Analysis of Lipid: Each 5 test fish were collected from acclimation bath 2 days before exposure start and from control bath 4 days after exposure end to measure lipid content. Measurement was conducted based on Method of E.G. Bligh ad W.J. Dyer. As a result, lipid contents were 4.9% w/w (mean) for 2 days before exposure start and 4.5% w/w (mean) for 4 days after exposure end.

Route of exposure:

aqueous

Test type:

flow-through

Water / sediment media type:

natural water: freshwater

Total exposure / uptake duration:

ca. 28 d

Test temperature:

25±2degreesC

pH:

pH values were 7.4 for dilution bath, Group 1 and Control, and 7.4 – 7.5 for Group 2.

Dissolved oxygen:

Group 1 6.3 – 6.5 mg/L
Group 2 6.4 – 6.7 mg/L
Control 7.1 – 7.4 mg/L

Details on test conditions:

Test and Environmental Condition
(1) Method for Test Water Supply: Flow-through bioconcentration study equipment (Series
1) which was assembled in the laboratory was used.
(2) Test Bath: 100 L Glass Water Bath (3 pcs) was used.
(3) Quantity of Test Water: 1000 mL/min. (stock solution flow rate: 6.0 mL/hour)
(4) Test Temperature: 25±2oC
(5) Lighting Period: 16 hours/day (commercially available fluorescent bulb)
(6) Dissolved Oxygen: Group 1 6.3 – 6.5 mg/L (see Fig. 2)
Group 2 6.4 – 6.7 mg/L (see Fig. 2)
Control 7.1 – 7.4 mg/L (see Fig. 2)
(7) Number of Test Fish: Group 1 and 2 35 fish (at exposure start)
Control 10 fish (at exposure start)
(8) Exposure Condition: After test substance concentration in test water was confirmed to reach to the nominal concentration of test water, test fish was subjected to the study within each test bath.
(9) Exposure Period: 28 days
(10) Test Location: B204 (Bioconcentration Study Room)

Nominal and measured concentrations:

Above standard solution (1000 mg/L, total value) was serially diluted with Acetonitrile/H2O(80/20, v/v) to prepare solutions for creation of calibration curve with concentrations of 0.200, 1.00, 2.00, 4.00 and 7.00 mg/L (total value each).

Key result

Conc. / dose:

0.2 mg/L

Temp.:

25 °C

pH:

7.4

Type:

BCF

Value:

< 3.2 dimensionless

Calculation basis:

steady state

Remarks on result:

other: Group 1

Key result

Conc. / dose:

0.02 mg/L

Temp.:

25 °C

pH:

7.4

Type:

BCF

Value:

< 31 dimensionless

Calculation basis:

steady state

Remarks on result:

other: Group 2

Details on results:

Visual observation for change of appearance and feeding condition of test fish was conducted on every working day. No abnormality was observed.
Abnormality of Test Fish: No mortality or abnormality including sickness was observed for Group 1, 2 and Control.
Environmental Factors that might have affected the reliability of the test results. None.

BCFs (total value) obtained from measurements on Day 4, 7, 14, 21 and 28 were <3.1 - <3.9 for Group 1, <30 - <37 for Group 2, respectively.
Since BCFs (total value) obtained from measurements on Day 14, 21 and 28 were <3.3 - <3.3 for Group 1 and <30 - <32 for Group 2, respectively, it was determined as steady state and exposure was completed.
Degrees of bioaccumulation of test substance for carp based on BCF (total value) under steady state were <3.2 for Group 1 and <31 for Group 2.
Measured values from test water analysis (total value) were 0.197 – 0.200 mg/L for Group 1 and 0.0195 – 0.0200 mg/L for Group 2, and nominal values were retained.

No abnormalities for appearance and behavior of test fish were observed during test.

Validity criteria fulfilled:

yes

Conclusions:

Bioconcentration Factor (Equilibrium)
Group 1: <3.2 (sum)
Group 2: <31 (sum)
(BCF under steady state could not be calculated.)

Executive summary:

1. Study Number and Study Title 0537C, Bioconcentration Study of T-1226A in Common Carp

2. Test Condition -2.1 Acute Toxicity Study

(1) Test Fish: Oryzias latipes

(2) Exposure Period: 96 hours

(3) Exposure Method: Semi-static (renewing test water at every 24 hours)

2.2 Bioconcentration Study

(1) Test Fish: Common carp

(2) Test Concentration: Group 1: 0.20 mg/L

Group 2: 0.020 mg/L

(2) Exposure Period: 28 days

(3) Exposure Method: Continuous flow-through

(4) Analytical Method: HPLC

3. Test Results

(1) 96 hr LC50 of the Test Substance: >20 mg/L

(2) Bioconcentration Factor (Equilibrium)

Group 1: <3.2 (sum)

Group 2: <31 (sum)

(BCF under steady state could not be calculated.)

4. Stability of Test Substance

Test substance was confirmed to be stable under the storage condition and test condition.

Materials and methods

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of 2-(1,1-dimethylethyl)-4-{[5-(1,1-dimethylethyl)-4-hydroxy-2-methylphenyl]thio}-5-methylphenyl 3-(dodecylthio)propionate and thiobis[2-(1,1-dimethylethyl)-5-methyl-4,1-phenylene] bis[3-(dodecylthio)propionate]

EC Number:

940-594-7

Molecular formula:

C52H86O4S3 , C37H58O3S2

IUPAC Name:

Reaction mass of 2-(1,1-dimethylethyl)-4-{[5-(1,1-dimethylethyl)-4-hydroxy-2-methylphenyl]thio}-5-methylphenyl 3-(dodecylthio)propionate and thiobis[2-(1,1-dimethylethyl)-5-methyl-4,1-phenylene] bis[3-(dodecylthio)propionate]

Test material form:

liquid

Details on test material:

Intended use: Antioxidant for plastics
Appearance: Brown liquid
Storage conditions: Room temperature protected from light
Supplier: Sponsor
Lot number: 102Y1
Expiry date: 30 April 2014
Purity 98.8%

Results and discussion

Bioaccumulation factor

Bioaccumulation factor 1

Key result

Conc. / dose:

0.2 mg/L

Temp.:

25 °C

pH:

7.4

Type:

BCF

Value:

< 3.2 dimensionless

Calculation basis:

steady state

Remarks on result:

other:

Remarks:

Group 1

Bioaccumulation factor 2

Key result

Conc. / dose:

0.02 mg/L

Temp.:

25 °C

pH:

7.4

Type:

BCF

Value:

< 31 dimensionless

Calculation basis:

steady state

Remarks on result:

other:

Remarks:

Group 2