1-bromo-3,4,5-trifluorobenzene

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:

1998-09-23

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))

Version / remarks:

1997

Deviations:

no

GLP compliance:

yes

Type of method:

HPLC estimation method

Media:

soil

Radiolabelling:

no

Test temperature:

35 °C

Details on study design: HPLC method:

EQUIPMENTS
- Apparatus: HPLC system with Spectrophotometric detector
- Type, material and dimension of analytical column: Hypersil BDS-CN; column size: 150 x 4.6 mm; particle size: 5 µm, column temperature: 35 °C.
Detection: UV at A=210 nm

REAGENTS
Methanol: Labscan Limited Co., Dublin, Ireland
Acetonitrile: Labscan Limited Co.
Milli-Q water: Millipore Corp., Bedford, MA, USA
Formamide: Merck

DETERMINATION OF DEAD TIME
- Method: by using a "dead time marker"

MOBILE PHASES
- Type: 30/70 (v/v) methanol / Milli-Q water
- Experiments with additives carried out on separate columns: no
- Solutes for dissolving test and reference substances: methanol

REFERENCE SUBSTANCES
- Identity: Phenol, Methylbenzoate, Naphtalene, Mercaptodimethur, Fenthion and Phenantrene.

REPETITIONS
- Number of determinations: 2

Key result

Type:

log Koc

Value:

2.47 dimensionless

Temp.:

35 °C

Key result

Type:

Koc

Value:

292 L/kg

Temp.:

35 °C

Table 1: Determination of the Dead Time t_o

Dead time marker	to in min 1^st Measurement	to in min 2^nd Measurement	to in min Mean
Formamide	2.014	2.013	2.014

Dead time: t_o = 2.014

Table 2: Results of the test

Substance	tr^*	K^*	Log K^*	Log Koc	Koc
Reference Substance
Phenol	2.95	0.466	-0.331	1.32
Methylbenzoate .	4.09	1.03	0.013	1.80
Naphtalene	7.47	2.71	0.433	2.75
Mercaptodimethur	8.15	3.05	0.484	3.10
Fenthion	24.1	10.98	1.041	3.31
Phenantrene	21.6	9.72	0.988	4.09
Test substance
Peak	6.09	2.03	0.306	2.47^**	292

^*  Mean value of the retention times of both chromatograms.

^** Interpolated from the regression line: y = 0.5012x - 0.9294 (r = 0.9501, n = 6)

Validity criteria fulfilled:

yes

Conclusions:

The adsorption coefficient of the item was found to be log Koc = 2.47 at 35 °C. The Koc was 292 L/kg at 35 °C.

Executive summary:

A study according to OECD 117 and OECD 121 was performed to determine the adsorption coefficient log K_oc of the test item. The HPLC method was used. A series of reference substance, in accordance with OECD 121, was used as the calibration series for the HPLC measurements. Two series were injected. The series included the reference substances and the test item. The test item was injected in-between the series of the reference substances. The dead time to was determined by measuring the retention time of a dead time marker – Formamide. The dead time marker was dissolved in methanol and was diluted by a factor 10 with 30:70 % (v/v) methanol/Milli-Q water and injected as single standard twice. The reference substances were dissolved in methanol at concentrations between 1 and 2 g/L with the mobile phase methanol/Milli-Q water 30:70 % (v/v) and injected as standard twice. A 2.09 g/L stock solution of the test item was prepared in acetonitrile, diluted by a factor of 100 with 30:70 % (v/v) methanol/Milli-Q water and injected twice. A 1% solution of acetonitrile in 30:70 % (v/v) methanol/Milli-Q water was used as blank. The chromatograms were recorded for 45 minutes. The adsorption coefficient of the item was found to be log K_oc = 2.47 at 35 °C. The K_oc was 292 L/kg at 35 °C.

Description of key information

The adsorption coefficient of the item was found to be log Koc = 2.47 at 35 °C. The Koc was 292 L/kg at 35 °C.

Key value for chemical safety assessment

Koc at 20 °C:

292

Additional information

A study according to OECD 117 and OECD 121 was performed to determine the adsorption coefficient log K_oc of the test item. The HPLC method was used. A series of reference substance, in accordance with OECD 121, was used as the calibration series for the HPLC measurements. Two series were injected. The series included the reference substances and the test item. The test item was injected in-between the series of the reference substances. The dead time to was determined by measuring the retention time of a dead time marker – Formamide. The dead time marker was dissolved in methanol and was diluted by a factor 10 with 30/70 (v/v) methanol/Milli-Q water and injected as single standard twice. The reference substances were dissolved in methanol at concentrations between 1 and 2 g/L with the mobile phase methanol/Milli-Q water 30:70 % (v/v) and injected as standard twice. A 2.09 g/L stock solution of the test item was prepared in acetonitrile, diluted by a factor of 100 with 30:70 % (v/v) methanol/Milli-Q water and injected twice. A 1% solution of acetonitrile in 30:70 % (v/v) methanol/Milli-Q water was used as blank. The chromatograms were recorded for 45 minutes. The adsorption coefficient of the item was found to be log K_oc = 2.47 at 35 °C. The K_oc was 292 L/kg at 35 °C.