AERO 5100 PROMOTER

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:

21 May - 04 Jun 1998

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: OECD Draft Document TGP/94.75 (April 1994)

Qualifier:

equivalent or similar 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

Type of method:

HPLC estimation method

Media:

soil

Radiolabelling:

no

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: Hewlett Packard 1050 Liquid Chromatograph
- Type, material and dimension of analytical (guard) column: Hypersil 5µm CPS (25 cm x 4.6 mm i.d.); column temperature: 30 °C; flow rate: 0.5 mL/min; injection volume: 10 µL
- Detection system: UV set at 215 nm

MOBILE PHASES
- Type: Methanol : water (55 : 45 v/v)

DETERMINATION OF DEAD TIME
- Method: by inert substances which are not retained by the column: Formamide

REFERENCE SUBSTANCES
- Identity: Phenol, Bromobenzene, Naphthalene, Butylbenzene, Antracene, DDT

Type:

log Koc

Value:

2.61 dimensionless

Type:

Koc

Value:

407 dimensionless

Details on results (HPLC method):

- Retention times of reference substances used for calibration: See "Any other information on results incl. tables"

Preliminary estimation:

A value for the adsorption coefficient Koc was estimated based on an empirical relationship with the partition coefficient Pow: log10 Koc = 0.37 log10 Pow + 1.14. The log10 Pow was determined to be 2.84. An estimated log10 Koc value of 2.19 was thus determined, which gave an equivalent Koc value of 155.

Table 1: HPLC determination of Koc

Sample	Component	tr (minutes)	k’	Log10 k’	Log10 Koc
Standard Run A (t0 = 6.268 minutes)	Phenol	7.287	0.163	-0.789	1.43
	Bromobenzene	9.054	0.444	-0.352	2.18
	Naphthalene	10.051	0.604	-0.219	3.04
	Butylbenzene	11.134	0.776	-0.110	3.40
	Anthracene	14.861	1.371	0.137	4.41
	DDT	25.959	3.142	0.497	5.38
Sample A (t0 = 6.269 minutes)	AERO® 5100 Promoter	9.034	0.441	-0.356	2.61
Sample B (t0 = 6.268 minutes)	AERO® 5100 Promoter	9.014	0.438	-0.358	2.60
Standard Run B (t0 = 6.269 minutes)	Phenol	7.282	0.162	-0.792	1.43
	Bromobenzene	9.037	0.442	-0.355	2.18
	Naphthalene	10.023	0.599	-0.223	3,04
	Butylbenzene	11.095	0.770	-0.114	3.40
	Anthracene	14.774	1.357	0.132	4.41
	DDT	25.712	3.101	0.492	5.38

Linear regression (based on mean of standard runs A and B): log10 Koc = 3.25 log10 k' + 3.77

Description of key information

log Koc: 2.61 (OECD Draft Document TGP/94.75)

Additional information

One experimental study is available investigating the adsorption potential of the substance (Cytec Industries, 1998). The study was performed according to OECD Draft Document TGP/94.75 (GLP; 1994) which in principle is comparable with OECD 121. Six reference substances with known log Koc values were used to estimate the log Koc of the test substance using HPLC method. The reference substances and the test substance samples were run in duplicate. By comparing the retention time of the reference substances with the retention time of the test substance it was possible to estimate the log Koc. The calculations resulted in a log Koc of 2.61 corresponding to a Koc of 407.