Reaction product of D-Glucopyranoside, methyl; esterified with oleic acid, methyl ester

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-04-01 - 2015-04-15

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guidline study in compliance with GLP

Qualifier:

according to guideline

Guideline:

EU Method C.19 (Estimation of the Adsorption Coefficient (KOC) on Soil and Sewage Sludge Using High Performance Liquid Chromatography (HPLC))

Version / remarks:

of 2008-05-30

Deviations:

no

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:

of 2001-01-22

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

The Department of Health of the Government of the United Kingdom

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Radiolabelling:

not specified

Test temperature:

30 °C

Details on study design: HPLC method:

Solutions of reference standards (Table 3.1) were prepared in methanol.
The dead time was determined by measuring the retention time of formamide (purity*: 99.94%) at 628 mg/L in methanol:water (55:45 v/v).
* value quoted by supplier
Test item (0.1018 g) was diluted to 10 mL with tetrahydrofuran.
The sample, dead time and reference standard solutions were injected in duplicate using the following high performance liquid chromatography (HPLC) parameters:
HPLC System: Agilent Technologies 1200, incorporating workstation and autosampler
Detectors: Agilent variable wavelength detector (VWD) and Polymer Laboratories evaporative light scattering detector 2100 (ELSD)
Column: Water XSelect CN 5 micrometer (150 x 4.6 mm id)
Column temperature: 30 °C
Flow-rate: 1.0 mL/min
Mobile phase: methanol : purified water (55 : 45 v/v)
pH of mobile phase 5.9
Injection volume: 5 microliter
UV detector wavelength (dead time and reference standarts): 210 nm
ELSD parameters (sample): nebuliser temperature: 40 °C
evaporater temperature: 80 °C
gas flow: 1.0 L/min
The mobile phase was ramped to 100% propan-2-ol shortly after the elution of the last reference standard to elute the highly retained test item components. This was carried out for the sample and sample blank injections only.
The capacity factors were determined using the following equation:
k' = ((tr - t0) / (t0))
where: k' = capacity factor
tr = retention time (min)
t0 = dead time (min)
Construction of the calibration curve:
A correlation of log10 k' versus log10 Koc of the calibration standards was plotted using linear regression (Figure 3.1). The capacity factor (k') for the reference standards was calculated from the retention time data of the dead time and reference standard solutions using Equation 3.1. Log10 Koc values of the reference standards are those quoted in OECD Method 121.
Adsorption Coefficient:
The capacity factor of the test item was calculated using Equation above. The Log10 Koc value was calculated using Equation below with reference to the calibration curve (Figure 3.1)
Log10 Koc = ((Log 10 k' - A) / (B))
where: Koc = adsorption coefficient
k' = capacity factor
A = intercept of the calibration curve (Figure 3.1)
B = slope ot the calibration curve (Figure 3.1)

Analytical monitoring:

not required

Key result

Type:

Koc

Value:

> 427 000 dimensionless

Key result

Type:

log Koc

Value:

> 5.63 dimensionless

Details on results (HPLC method):

Typical Chromatography is shown for Dead time, Reference Standard - Diclofop Methyl and the Sample.
The retention times of the dead time and the retention times, capacity factors and log10 Koc values for the reference standards are shown in Table 3.2 and Table 3.3.
Calibration Curve is shon in Figure 3.1.
The retention times, capacity factor and log10 Koc value determined for the sample are shown in Table 3.4.
The mobile phase's pH was unadjusted as the majority of the components of the test item (products >95%) had no dissociation constant with in the environmentally relevant pH range so they were tested in their non-ionized form. A number of peaks, mostly small, were observed in the sample chromatography which represented other components within the test item but were not included in the test result as they were considered insignificant with respect to the test item as a whole. One of these peaks, occurring at approximately 0.8 minutes, was significant in its peak area but even so, it was not included as part of the overall test result. This was because, the Sponsor's information on the test item detailed water soluble inorganic salts which could explain the peak eluting before the dead time. Also, it explains that although the salt's abundance is not significant its peak area is. This is because the ELSD can have significant sensitivity to nonvolatile inorganic salt.

Adsorption and desorption constants:

not required

Table 3.2:

Dead Time	Retention Time (mins)		Mean Retention Time (mins)
	Injection 1	Injection 2
Formamide	1.921	1.924	1.923

Table 3.3:

Standard	Retention Time (mins)		Mean Retention Time (mins)	Capacity Factor (k')	Log10k'	Log 10 Koc
	Injection 1	Injection 2
Acetanilide	2.623	2.623	2.623	0.364	-0.439	1.25
Atrazine	3.598	3.600	3.599	0.872	-5.95 x 10^-2	1.81
Isoproturon	3.836	3.833	3.834	0.994	-2.47 x 10^-3	1.86
Triadimenol	5.085	5.087	5.086	1.65	0.216	2.40
Linuron	5.199	5.201	5.200	1.71	0.232	2.59
Naphthalene	4.529	4.527	4.528	1.36	0.132	2.75
Endosulfan-diol	6.354	6.361	6.357	2.31	0.363	3.02
Fenthion	7.598	7.613	7.606	2.96	0.471	3.31
cc-Endosulfan	10.670	10.679	10.674	4.55	0.658	4.09
Diclofop-methyl	11.492	11.487	11.490	4.98	0.697	4.20
Phenanthrene	8.290	8.292	8.291	3.31	0.520	4.09
DDT	22.307	22.312	22.310	10.6	1.03	5.63

Table 3.4:

Injection	Retention Time (mins)	Capacity Factor (k')	Log10k'	Log10Koc	Mean Log10Koc	Adsorption Coefficient
1	>=34.577	>10.6	>1.03	>5.63	>5.63	>4.27x 10^5
2	>=34.550	>10.6	>1.03	>5.63

Validity criteria fulfilled:

not specified

Conclusions:

The adsorption coefficient of the test item has been determined to be greater than 4.27 x 10E5, log10 Koc >5.63, for more than 95% of the test item.

Executive summary:

This study estimates the adsorbtion coefficient ot the test item: Greater than 4.27 x 10E5, log10 Koc >5.63, for more than 95% of the test item, using the HPLC screening method, designed to be compatible with C 19 Adsorption Coefficient of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 121 ofthe OECD Guidelines for Testing of Chemicals, 22 January 2001.

Description of key information

This study estimates the adsorbtion coefficient ot the test item: Greater than 4.27 x 10E5, log10 Koc >5.63, for more than 95% of the test item, using the HPLC screening method, designed to be compatible with C 19 Adsorption Coefficient of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 121 of the OECD Guidelines for Testing of Chemicals, 22 January 2001.

Key value for chemical safety assessment

Koc at 20 °C:

427 000

Additional information

Key values for chemical safety assessment are not at 20 °C, but at 30 °C, because of the HPLC-method and the values are greater than the inscribed estimated values!

An additional QSAR calculation was performed.

The prediction for soil adsorption property of the substance D-glucopyranoside methyl 2,6 -dioleate was determined by the computer program KOCWIN v2.00 (EPIWIN software) by US-EPA (Chemservice S.A., 2017). The program estimates the organic-normalized sorption coefficient for soil, which is designated as Koc. The following two models are used: the Salbjic molecular connectivity (MCI) method as well as the traditional method which is based on the logPow value of the substance. The MCI method is taken more seriously into account, due to the fact that is includes improved correction factors, resulting a Koc value of 4.238E6 L/kg. The traditional method gives a value of 3512 L/kg.

[LogKoc: 5.63]