6,6'-di-tert-butyl-4,4'-butylidenedi-m-cresol

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:

07 May 2012 to 06 July 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed in accordance with OECD & EU test guidance in compliance with GLP.

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other 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))

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))

GLP compliance:

yes

Type of method:

HPLC estimation method

Media:

other: soil-adsorption-reference data

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not specified

Radiolabelling:

no

Details on study design: HPLC method:

Instrument: Alliance Separation Module 2695 (Waters, Milford, MA, USA)
Detector: Dual λ Absorbance Detector 2487 (Waters)
Column: Hypersil BDS-CN, 150 mm x 4.6 mm i.d., dp = 5 μm (Thermo Fisher Scientific, Waltham, MA, USA)
Column temperature: 35°C ± 1°C
Mobile phase: 55/45 (v/v) methanol/water
Flow: 1 ml/min
Injection volume: 10 μl
UV detection: 210 nm

Preparation of the solutions
Solution of the unretained compound: A 5.61 g/l stock solution of formamide (99.8%, [75-12-7], Acros Organics, Geel, Belgium) in methanol was used. The stock solution was diluted to obtain an end solution of 55/45 (v/v) methanol/water.
The formamide blank solution was 55/45 (v/v) methanol/water.
Reference substance solutions: Stock solutions of the reference substances at concentrations of approximately 1 g/l in methanol were used. The stock solutions were diluted to obtain an end solution of 55/45 (v/v) methanol/water.
The blank solution for the mixture of reference substances was 55/45 (v/v) methanol/water.
Test solution: A 1004 mg/l stock solution of the test substance was prepared in methanol. The stock solution was diluted to obtain an end solution of 55/45 (v/v) methanol/water. The final concentration of the test substance solution was 10.0 mg/l.
The test substance blank solution was 55/45 (v/v) methanol/water.
Injections: The reference substance and test substance solutions were injected in duplicate. Blank solutions were analysed by single injection.

Type:

log Koc

Value:

5.48

Details on results (HPLC method):

In the chromatogram of the test solution, one test substance peak was observed.
The results of the HPLC method show the calibration curve of the log k’ of the reference substances as function of log Koc. The equation of the regression line was:
log k’ = 0.281 x log Koc – 1.17 (r = 0.98, n = 16).

K_ocof the test substance

Substance	tr1 [min]	tr2 [min]	Mean tr(n=2)	Log Koc	Koc
Formamide (t0)	1.980	1.981	1.981
Acetanilide	2.223	2.221		1.26
Atrazine	2.400	2.397		1.81
Monuron	2.446	2.448		1.99
2,5-Dichloroaniline	2.702	2.704		2.55
Benzoic acid phenylester	2.943	2.937		2.87
Fenthion	3.662	3.669		3.31
Phenanthrene	3.775	3.764		4.09
4,4’-DDT	6.208	6.220		5.63
Test substance	6.635^1	6.615^1	6.625	5.48	3.0 x 10^5

 ¹Obtained by extrapolation of the calibration curve.

Validity criteria fulfilled:

yes

Conclusions:

The Koc and log Koc value of the test substance and impurities at neutral pH was:
Koc : 3.0 x 105
log Koc: 5.48

Executive summary:

Study performed in accordance with European Community (EC), EC no. 440/2008, Part C: Methods for the Determination of Ecotoxicity, Guideline C.19: “Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC)”, OECD Guideline for the Testing of Chemicals no. 121: "Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC)” and in compliance with the Principles of Good Laboratory Practice (GLP).

 

The HPLC method using soil-adsorption-reference data was applied for the determination of the adsorption coefficient (Koc) of 6,6’-di-tert-butyl-4,4’-butylidenedi-m-cresol.

The Kocand log Kocvalue of the test substance and impurities at neutral pH was:

K_oc: 3.0 x 10⁵

log K_oc: 5.48

Description of key information

Key value determined by HPLC estimation method in compliance with OECD & EU test guidance.

Koc : 3.0 E+5

log Koc: 5.48

Key value for chemical safety assessment

Koc at 20 °C:

300 000

Additional information

[LogKoc: 5.48]