3-[(3-sulfanylbutanoyl)oxy]-2,2-bis{[(3-sulfanylbutanoyl)oxy]methyl}propyl 3-sulfanylbutanoate

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:

09 Jan 2009

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

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:

adopted in 2001

Deviations:

yes

Remarks:

Test material components were only tested in their non-ionised forms

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:

adopted in 2008

GLP compliance:

yes (incl. QA statement)

Remarks:

The Department of Health of the Government of the United Kingdom, date of inspection 19 Aug 2008

Type of method:

HPLC estimation method

Radiolabelling:

no

Test temperature:

40 ºC

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: HPLC
- Type: Agilent Technologies 1100
- Type, material and dimension of analytical (guard) column: Zorbax SB CN 5 µm, 250 x 4.6 mm
- Detection system: UV detector, 210 nm standards, 220 nm samples

MOBILE PHASES
- Type: 55% acetonitrile/45% water (v/v)
- pH: 7.2
- Solutes for dissolving test and reference substances: acetonitrile

DETERMINATION OF DEAD TIME
- Method: The retention time of formamide (purity ≥ 99.5%, 1430 mg/L solution in mobile phase)

REFERENCE SUBSTANCES
- Identity: Acetanilide, Phenol, Atrazine, Isoproturon, Triadimenol, Linuron, Naphthalene, Endosulfan-diol, Fenthion, α-Endosulfan, Phenanthrene, Diclofop-methyl, DDT

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 20 µL of 1014 mg/L solution
- Quantity of reference substances: 20 µL of 100 to 139 mg/L solutions

REPETITIONS
- Number of determinations: 2

Key result

Type:

Koc

Value:

33 700

Temp.:

40 °C

Remarks on result:

other: PEMB

Key result

Type:

log Koc

Value:

4.53

Temp.:

40 °C

Remarks on result:

other: PEMB

Key result

Type:

Koc

Value:

1 050

Temp.:

40 °C

Remarks on result:

other: PE3MB

Key result

Type:

log Koc

Value:

3.02

Temp.:

40 °C

Remarks on result:

other: PE3MB

Details on results (HPLC method):

- Retention times of reference substances used for calibration: see Table 1
- Details of fitted regression line (log k' vs. log Koc): y = 0.249x - 0.713, r2 = 0.974
- Average retention data for test substance: Component A (PE3MB): 5.42 min, Component B (PEMB): 9.32 min
- Capacity factor for test substance: Component A (PE3MB): 1.096, Component B (PEMB): 2.602

Transformation products:

no

Table 1: Retention times of reference substances used for calibration

Standard	Mean Retention Time (min)	Log Koc
Acetanilide	3.362	1.25
Phenol	3.462	1.32
Atrazine	4.163	1.81
Isoproturon	4.250	1.86
Triadimenol	4.678	2.40
Linuron	5.055	2.59
Naphthalene	5.440	2.75
Endosulfan-diol	5.113	3.02
Fenthion	6.820	3.31
α-Endosulfan,	8.694	4.09
Phenanthrene,	7.056	4.09
Diclofop-methyl	8.377	4.20
DDT	12.840	5.63

Table 2: Data for Component A (PE3MB)

Injection	Retention Time (min)	Capacity Factor (k)	Log10k	Log10Koc
1	5.423	1.095	3.94 x 10^-2	3.02
2	5.429	1.097	4.04 x 10^-2	3.02

Mean log₁₀K_oc:                     3.02
Adsorption coefficient:        1.05 x 10³

Table 3: Data for Component B (PEMB)

Injection	Retention Time (min)	Capacity Factor (k)	Log10k	Log10Koc
1	9.318	2.600	0.415	4.53
2	9.328	2.604	0.416	4.53

Mean log₁₀K_oc:                     4.53
Adsorption coefficient:        3.37 x 10⁴

Conclusions:

The log Koc for the two components is as follows:
Component A (PE3MB): 3.02
Component B (PEMB): 4.53

Executive summary:

Adsorption Coefficient: The adsorption coefficient was determined using the HPLC screening, Method C19 Adsorption Coefficient of Council Regulation (EC) No 440/2008 of 30 May 2008 and Method 121 of the OECD Guidelines for Testing of Chemicals, 22 January 2001. 

The results are shown in the following table:

Component	Adsorption Coefficient	Log10 Koc
A	1.05 x 10^3	3.02
B	3.37 x 10^4	4.53

Description of key information

Log Koc = 4.53 at 40 °C (HPLC estimation method, OECD 121)

Key value for chemical safety assessment

Koc at 20 °C:

33 700

Additional information

The adsorption/desorption potential of the test material was analysed in a HPLC screening study (key) following OECD guideline 121 and GLP (Showa Denko, 2009). The test substance was analysed for its elution behaviour by comparison to 13 reference substances unsing a HPLC method. According to the established calibration curve, the value for the log Koc of the test substance is 4.53 (Koc 33700).

[LogKoc: 4.53]