β-methyl-3-(1-methylethyl)benzenepropanal

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:

24 February 2012 to 09 March, 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline 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))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

other: HPLC Screening Method - Mobile Phase MeOH / H2O (55/45 v/v)

Specific details on test material used for the study:

Lot No. SC00002800
Purity 98.3%.
Date of Expiry : 23 May, 2012

Radiolabelling:

no

Details on study design: HPLC method:

Principle of the method :

Reverse phase High Performance Liquid Chromatography on cyanopropyl-modified silica stationary phase, containing lipophilic and polar moieties, is used.

While passing through the column among with the mobile phase the test substance interacts with the stationary phase. As a result of the partitioning between the mobile and stationary phase the test substance is retarded. The dual-composition of the stationary phase having polar and non-polar sites allows for interaction of polar and non-polar groups of a molecule in a similar way as it is the case for organic matter in soil or sewage sludge matrices. This enables the relationship between the retention time on the column and the adsorption coefficient on organic matter to be established.

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.


Equipment and conditions :
HPLC equipment: Perkin Elmer (series 200) HPLC system comprising:
- a high pressure pump (module N2910102, serial number: 291N8051901A)
- an auto-sampler (module N2930100, serial number: 293N8052404A)
- a column compartment (module N2601581, serial number: OVH0802151130)
- a refractive index detector (series 200a, serial number 125829).


- Column : 250 mm x 4.6 mm, Nucleodur 100-5 CN-RP
(Macherey-Nagel)
serial number: N10080027, batch 34518023

- Mobile phase : methanol / water 55/45 (v/v))

- Flow rate : 1.0 ml/min.

- Column temperature : 35 °C

- Injected volume : 100 µl

Key result

Type:

log Koc

Value:

2.87 L/kg

Temp.:

35 °C

Remarks on result:

other: HPLC Method (OECD 121).

Remarks:

The determination was performed at 35 °C (temperature of the column), but the value obtained above can be considered to represent the value at an unspecified, probably ambient temperature since no mention is made in the guidelines of the temperature at which the tabulated reference substances log KOC values were determined. Adsorption coefficients of the test and reference substances are assumed to vary with temperature in the same way.

Details on results (HPLC method):

The determination was performed at 35 °C (temperature of the column), but the value obtained above can be considered to represent the value at an unspecified, probably ambient temperature since no mention is made in the guidelines of the temperature at which the tabulated reference substances log KOC values were determined. Adsorption coefficients of the test and reference substances are assumed to vary with temperature in the same way.


The chromatograms of Florhydral show one peak at an average retention time of 5.607 minutes, corresponding to an adsorption coefficient (log value) of 2.87.

Transformation products:

no

Reference Substances :

Test Substance - FLORHYDRAL :

Validity criteria fulfilled:

yes

Conclusions:

logKOC of FLORHYDRAL = 2.87 L/kg (741).
FLORHYDRAL is therefore likely to have an INTERMEDIATE level of adsorption to soil, sediment and sewage sludge.

Description of key information

LogKoc of FLORHYDRAL = 2.87 L/kg (741).

FLORHYDRAL is therefore likely to have an INTERMEDIATE level of adsorption to soil, sediment and sewage sludge.

Key value for chemical safety assessment

Koc at 20 °C:

741

Additional information

LogKoc of FLORHYDRAL = 2.87 L/kg (741).

FLORHYDRAL is therefore likely to have an INTERMEDIATE level of adsorption to soil, sediment and sewage sludge.