Distilled acetalization product between glucose and C12-18(even numbered)alcohol

Adsorption / desorption

Administrative data

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD guideline, GLP study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

2011

Materials and methods

Test guideline

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))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Test material

Test material information

Constituent 1

Reference substance name:

LCE10034-distilled acetalization product between glucose and C12/18 alcohol

IUPAC Name:

LCE10034-distilled acetalization product between glucose and C12/18 alcohol

Details on test material:

Identification LCE10034-distilled acetalization product between glucose and C12/18 alcohol
Expiry date Not provided
Supplier SEPPIC
Appearance White Pearls
Packaging 1 White plastic flask with blue stopper
Quantity received 1 x 400 g
Date of the reception 30 March 2010
Storage In darkness at room temperature
Identification number of the test item 10-059

Radiolabelling:

no

Study design

Test temperature:

around 22°C

HPLC method

Details on study design: HPLC method:

Analytical method for the adsorption/desorption coefficient determination
Reagents
Acetone for analysis
Methanol for HPLC
Water for HPLC
All the glassware was rinsed with acetone for analysis and air dried before use.

Apparatus
Autosampler Hitachi AS2000A
HPLC pump Hitachi L-6200A
UV visible detector Hitachi L-4250
Ultrasonic tank Transonic Type T425H
Magnetic stirrer Heidolph 94360
Balance: Accuracy  0.1 mg Mettler AE 100S
Usual laboratory apparatus

Safety instructions
The chemicals, solvents and equipment were used with caution. The safety rules defined within DEFITRACES were strictly followed.

Preparation of the mobile phase
A volume of 550 mL of water was transferred into a one-Liter glass flask. A volume of 450 mL of methanol was added. The solution was treated with ultrasounds for
5 minutes and left to stand for 10 minutes before analysis.

Preparation of the thiourea solution
The thiourea solution was prepared at a concentration of about 800 mg/L and diluted 100 then 1.5 fold with methanol/water 45/55 v/v before analysis.
This diluted solution was used for the t0 determination.

Preparation of the analytical reference item solutions
Acetanilide, methylbenzoate, isoproturon, 1,2,3-trichlorobenzene, pyrazophos and 4,4’-DDT are the six reference items solutions chosen within the method recommended reference substances for the HPLC method.
For acetanilide and 4,4’-DDT: A quantity of about 10 mg (to the nearest ± 0.1 mg) of reference item was weighed into a 100-mL volumetric flask. The volume was made up with methanol. The solution was treated with ultrasounds during 5 minutes then diluted 20 fold for acetanilide and 5 fold for 4,4’-DDT in methanol/water 45/55 v/v.
For 1,2,3-trichlorobenzene and pyrazophos: A quantity of about 20 mg (to the nearest ± 0.1 mg) of reference item was weighed into a 100-mL volumetric flask. The volume was made up with methanol. The solution was treated with ultrasounds during 5 minutes then diluted 10 fold in methanol/water 45/55 v/v.
For isoproturon and methylbenzoate: A quantity of about 20 mg (to the nearest ± 0.1 mg) of reference item was weighed into a 25-mL volumetric flask. The volume was made up with methanol. The solution was treated with ultrasounds during 5 minutes then diluted
83 fold for isoproturon and 20 fold for methylbenzoate.

Preparation of the mixed analytical reference item solutions
Volumes of 1 mL of acetanilide, 1 mL of methylbenzoate, 0.25 mL of isoproturon,
2 mL of pyrazophos, 2 mL of 1,2,3-trichlorobenzene and 4 mL of 4,4’-DDT were transferred into a 20-mL volumetric flask. The volume was made up with the mixture of methanol/water 45/55 v/v.
A vial was prepared for analysis.

Preparation of the test item solution
A quantity of about 1000 mg of LCE10034-distilled acetalization product between glucose and C12/18 alcohol was accurately weighed into a 100-mL volumetric flask. The volume was made with up methanol. The solution was treated with ultrasounds for
30 minutes before analysis.

Instrumental analysis
The experimental conditions used for the determination of the retention times of the analytical reference items and of the test item by high pressure liquid chromatography equipped with an ultraviolet detector are as following:

Column
Column Supelco Length (cm) 25
Particle size (μm) 5.0 Internal diameter (mm) 4.6
Stationary phase Supelcosil LC-CN
Mobile phase Methanol / water 45/55 v/v
Flow rate (mL/min) 0.9
Injected volume (μL) 40 Wave length analysis (nm) 210

Injection sequence
Mixture of the analytical reference items, test item, mixture of the analytical reference items, test item, mixture of the analytical reference items, individual analytical reference items.

Batch equilibrium or other method

Analytical monitoring:

yes

Computational methods:

The structure of the substances which make up the test item have a long non-polar chain and a hydrophilic part. Thus, the substances might exhibit surface-active properties.

The partition coefficients of the substances present in the test item as calculated during DEFITRACES’s study 10-919003-018 are very high; this is an indication of the hydrophobic nature of them.

A linear relationship exists between the adsorption/desorption coefficient and the partition coefficient of chemical substances. In the case of hydrophobic substances the relationship is given by the formula:

logKoc = 0.81 x log Pow + 0.10

The following table gives the calculated values of the adsorption/desorption coefficient of the substances defined in the test item.

Substances contained in
LCE10034 % in LCE10034 Value of log Pow Value of log Koc
Dodecanol About 1 4.8 4.0
Tetradecanol About 4 5.8 4.8
Hexadecanol About 6 6.7 5.5
Octadecanol About 28 7.7 6.3
Dodecylmonoglucoside About 15 2.9 2.4
Tetradecylmonoglucoside About 19 3.9 3.3
Hexadecylmonoglucoside About 9 4.9 4.1
Octadecylmonoglucoside About 19 5.8 4.8

The adsorption/desorption coefficient of LCE10034-distilled acetalization product between glucose and C12/18 alcohol can be estimated to be higher then 2.4 which represents the lowest value of Koc found for the substances which make up the test item.The calculated coefficients indicate that the more hydrophobic the substance is the more it tends to partition into the organic components of the soil and the sewage sludge and becomes associated with these materials

Results and discussion

Results: HPLC method

Details on results (HPLC method):

Using the HPLC experimental method for the estimation of the adsorption/desorption coefficient Kocon soil and on sewage sludge, no peaks related to the test item could be observed on the chromatographic trace in the interval limited by the reference substances. This result may be a consequence of an inadequate sensitivity of the analytical technique.
 
Therefore no experimental determination of the coefficient was made.

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Conclusions:

Based on the relationship existing between log Koc and log Pow, the adsorption/desorption coefficient of LCE10034-distilled acetalization product between glucose and C12/18 alcohol on soil and on sewage sludge can be estimated to be higher then 2.4.