Tetravinylsilane

Adsorption / desorption

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 2019-08-23 to 2019-09-04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))

Version / remarks:

2001

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Specific details on test material used for the study:

Batch No.: 707001
Purity: 98.5%

Radiolabelling:

no

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: HPLC 2695 system (C2019-003)
- Column: ECLIPSE XDB-CN (4.6×250 mm, 5 μm)
- Oven temperature: 30℃
- Detection wavelength: 210 nm
- Mobile phase: Methanol/Water =60/40
- Flow rate: 1.2 mL/min
- Injection volume: 5.0 µL

DETERMINATION OF DEAD TIME
- Method: The NaNO3 solution was injected for three times at the HPLC condition, and the average value of three retention times was considered to be the dead time t0

REFERENCE SUBSTANCES
- Identity: N,N-dimethylbenzamide, atrazine, naphthalene, triazophos, phenanthrene and p,p'-DDT

DETERMINATION OF RETENTION TIMES


REPETITIONS
- Number of determinations:
The injection sequence was as below:
(1) Inject reference substance individually for the first time, and record the tR1;
(2) Inject test item for one time, and record the tR;
(3) Inject reference substance individually for the second time, and record tR2;
The average value of tR1 and tR2 is calculated to be the tR of reference substance, which was employed in the k' calculation.


EVALUATION
- Calculation of capacity factors k': k'=(tR-t0)/t0
- Determination of the log Koc value: log Koc = a x lgk' + b

Type:

log Koc

Value:

2.75 dimensionless

Details on results (HPLC method):

- Retention times of reference substances used for calibration: 2.791, 3.165, 4.019, 4.442, 5.773, 9.615 min for N,N-dimethylbenzamide, atrazine, naphthalene, triazophos, phenanthrene and p,p'-DDT, respectively.
- Details of fitted regression line (log k' vs. log Koc): First calibration plot was log Koc=5.1954 × log k' + 1.6673, R2=0.9609; The second calibration plot: log Koc=5.2153 × log k' + 1.6688, R2=0.9610. The estimated log Koc of test item was 2.75.
- Average retention data for test substance: tR =3.999

Validity criteria fulfilled:

not specified

Conclusions:

The estimated log Koc of test item was 2.75.

Executive summary:

The HPLC method on the basis of OECD Test No. 121 was employed to estimate the Koc of test item. Six reference points including N,N-dimethylbenzamide, atrazine, naphthalene, triazophos, phenanthrene and p,p'-DDT were employed in the HPLC method. The estimated log Koc of test item was 2.75.

Reference 2

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 2019-08-23 to 2019-09-04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 106 (Adsorption - Desorption Using a Batch Equilibrium Method)

Version / remarks:

2000

Deviations:

yes

Remarks:

The recovery rate of moist soil exceeded the acceptable range. But the extent of deviation was little. It did not affect the test

GLP compliance:

yes (incl. QA statement)

Type of method:

batch equilibrium method

Media:

soil

Specific details on test material used for the study:

Batch No.: 707001
Purity: 98.5%

Radiolabelling:

no

Test temperature:

20-25 °C

Analytical monitoring:

yes

Details on sampling:

Both the concentration of aqueous phase and soil phase were measured on the 2nd and 4th hour to calculate the adsorption percentage and mass balance rate.

Matrix no.:

#1

Matrix type:

other: Paddy Soil

% Org. carbon:

1.14

pH:

6.88

Matrix no.:

#2

Matrix type:

other: Aquic brown soil

% Org. carbon:

1.19

pH:

5.47

Matrix no.:

#3

Matrix type:

other: Red Soil

% Org. carbon:

1.13

pH:

4.93

Matrix no.:

#4

Matrix type:

other: Black Soil

% Org. carbon:

1.16

pH:

6.54

Matrix no.:

#5

Matrix type:

other: Black Soil

% Org. carbon:

0.71

pH:

787

Details on matrix:

Soil type Batch No. Soil location
Paddy Soil 20170206 Huai'an, Jiangsu province
Aquic brown soil 20170901 Shenyang, Liaoning province
Red Soil 20170119 Qidong, Hunan province
Black Soil 20170308 Suihua, Heilongjiangprovince
Moisture soil 20150906-3 Heze, Shandong province

Details on test conditions:

Tier 1-preliminary test (Solution/soil ratio 5:1)
5.0 g soil with 25.0 mL solution (0.01mol/L CaCl2 solution) was agitated at 160rpm for at least 12h at 20~25°C in order to achieve pre-equilibrium. After pre-equilibration, 68 μLworking solution of 1814 mg/Lwas added into the aqueous phase to achieve a nominal concentration of 5 mg/L. And then another 4 hours agitation was run to reach adsorption equilibrium.
Both the concentration of aqueous phase and soil phase were measured on the 2nd and 4th hour to calculate the adsorption percentage and mass balance rate.
The two control units were also performed in same condition, 1) blank soil with 0.01mol/L CaCl2 solution but without the test item; 2) 0.01mol/L CaCl2 solution with the test item of 5 mg/L but without soil.

Computational methods:

The percentage of the chemical adsorbed (A, %) is calculated as:
A=Mad/MR x 100
Where：
A—Adsorption percentage, expressed as %
Mad—Mass of test item adsorbed on soil (μg)
MR—Residual mass of test item (μg)

The mass balance (MB, %) is calculated as follow:
MB=(Mt + Ce x Ve)/M0 x 100
Where:
Ce—Concentration of substance remaining in CaCl2 solution after adsorption equilibrium reached (µg/mL)
Ve—Volume of supernatant recovery after adsorption equilibriumreached (mL)
Mt—Mass of test item extracted from both the soil and aqueous phases in a tube after adsorption equilibrium reached (μg)
M0—Nominal mass of test item (μg)

Remarks on result:

not determinable

Remarks on result:

not determinable

Details on results (Batch equilibrium method):

PRELIMINARY TEST
The concentration in water and soil phases on the 2nd and 4th hour were all lower than the LOD, i.e.0.05 mg/L, so the adsorption percentage and mass balance were not able to be calculated. The test item was extremely unstable in the water/soil system. The initial concentration was set as 5mg/L, the control unit without soil on the 2nd hour was 4.140 and 4.045 mg/L, while that of the 4th hour was 3.360 and 3.350 mg/L, respectively.This also indicated that the test item was not stable in aquatic solution, which may be attributed into the volatility of the test item.

Validity criteria fulfilled:

not applicable

Conclusions:

The test item was extremely unstable in the water/soil system. The batch equilibrium method was not suitable the present test item.

Executive summary:

A batch equilibrium method was performed on the basis of OECD Guidelines No.106.

5.0 g soil with 25.0 mL solution (0.01mol/L CaCl2 solution) was agitated at 160 rpm for at least 12h at 20~25°C in order to achieve pre-equilibrium. After pre-equilibration, 68 μLworking solution of 1814 mg/Lwas added into the aqueous phase to achieve a nominal concentration of 5 mg/L. And then another 4 hours agitation was run to reach adsorption equilibrium.

However, the test item in the water/soil system was severely unstable during test period, the test item in both soil and water phases cannot be determined on the 2ndand 4thhour. The batch equilibrium method was not suitable the present test item.

Description of key information

The test item in the water/soil system was extremely unstable within 4 hours, which maybe attributed into the volatility of the test item. Due to batch equilibrium method was not suitable the present test item, the HPLC method was subsequently employed to estimate the Koc of test item. The estimated log Koc of test item was 2.75.

Key value for chemical safety assessment

Koc at 20 °C:

562.34