Reaction mass of 2-methylbutyl salicylate and pentyl salicylate

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:

Study initiation date: August 05, 2010. Study completion date: September 27, 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed according to GLP and 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))

GLP compliance:

yes (incl. QA statement)

Remarks:

Date of inspection: 17 and 18 March 2008. Date of signature: 23 June 2008

Type of method:

HPLC estimation method

Specific details on test material used for the study:

-Commercial name: Amyl Salicylate
-Chemical nature: Mixture of Pentyl 2-hydroxybenzoate and 3-Methylbutyl 2-hydroxybenzoate
-Givaudan Code No: 8810001
- Physical state: Liquid
- Analytical purity: 98.8% (sum of two isomers) 66.6% Pentyl 2-hydroxybenzoate; 32.2% 3-Methylbutyl 2-hydroxybenzoate
- Lot/batch No.: VE00100713
- Expiration date: September 10, 2011

Details on study design: HPLC method:

Equipment and procedures:
HPLC equipment: Perkin Elmer (series 200) HPLC system comprising:
- a high pressure pump (module N2910102, serial number: 291N8051901A)
- an autosampler (module N2930100, serial number: 293N8052404A)
- a column compartment (module N2601581, serial number: OVH0802151130)
- a variable wavelength detector (module N2920010, serial number: 292N8050804E)


- Column: 250 mm x 4.6 mm i.d., Nucelodur® 100-5 CN-RP (Macherey-Nagel) serial number: N8030929, batch 3034
- Mobile phase: methanol/water 55/45 (v/v))
- Flow rate: 1.0 ml/min
- Column temperature: 35°C
- detection wavelength: 210 nm
- Injected volume: 100µl


Reference substances:
Six substances were chosen having log Koc ranging from 1.45 to 5.63. Formamide is used as an unretained compound for the determination of the dead time t0.

Individual solutions of these seven substances in methanol were prepared at the concentrations given in Table 1.

HPLC procedure:
A solution of the test substance was prepared 10.0 mg in 20 ml methanol/water 55/45 v/v).

After equilibration of the HPLC system, the calibration mixture was injected first, followed by the test chemical solution twicw and the calibration mixture again.

Retention times tR were measured and averaged and the decimal logarithms of the capacity factors k were calculated. The linear regression parameters of the relationship

Log Koc = f(log k)

Were also calculated from the data obtained with the calibration mixture and, therewith, log Koc of the test substance was determined from its measured capacity factor.

Finally solutions of the reference substances were injected individually to confirm the peak assignment.

Type:

log Koc

Value:

3.7 dimensionless

Details on results (HPLC method):

The chromatograms of Amyl Salicylate show two partially resolved peaks at average retention times of 8.60 and 8.83 minutes. Both retention times correspond to adsorption coefficients (log value) of 3.7.
Detailed results are given in Appendix 1 and illustrated by the graph in Appendix 2.

Conclusions:

The adsorption coefficient (Koc) of Amyl Salicylate was log Koc = 3.7

Description of key information

The Adsorption coefficient (Koc) on soil and on sewage sludge of Amyl Salicylate was determined by the Reverse Phase High Performance Liquid Chromatographic Method according to OECD Guideline 121. The log Koc was 3.7, equivalent to a Koc of 5012.

Key value for chemical safety assessment

Koc at 20 °C:

5 012

Additional information

The chromatograms of Amyl Salicylate show two partially resolved peaks at average retention times of 8.60 and 8.83 minutes. Both retention times correspond to adsorption coefficients (log value) of 3.7.

[LogKoc: 3.7]