2,2,2-trichloroethane-1,1-diol

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Experimental test result performed using standard OECD test guidelines

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))

Principles of method if other than guideline:

Reverse Phase High Performance Liquid Chromatography on Octadecyl-modified silica based stationary phase is used.
Partitioning on the column occurs in order of hydrophobicity when a suitable mobile phase is used. From relationship between the measured retention times and the adsorption coefficient on organic matter of reference substances, the sorption coefficient of the test substance is calculated.

GLP compliance:

not specified

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Specific details on test material used for the study:

- Name of test material: 2,2,2-Trichloroethane-1,1-diol (Chloral hydrate)
- Molecular formula: C2-H3-Cl3-O2
- Molecular weight: 165.4026g/mol
- Smiles notation: C(C(O)O)(Cl)(Cl)Cl
- InChl: RNFNDJAIBTYOQL-UHFFFAOYSA-N
- Substance type: Organic
- Physical state: Solid

Radiolabelling:

not specified

Test temperature:

25°C

Details on study design: HPLC method:

The solutions of the test substance and reference substances were prepared in the mobile phase. Each of the reference substance and test substance were analysed by HPLC at 210 nm.
After equilibration of the HPLC system, Urea was injected first, the reference substances were injected in duplicate, followed by the test chemical solution in duplicate. Reference substances were injected again after test sample, no change in retention time of reference substances was observed.
Retention time tR were measured, averaged and the decimal logarithms of the capacity factors k were calculated. The graph was plotted between log Koc versus log k(Annex - 2).The linear regression parameter of the relationship log Koc vs log k were also calculated from the data obtained with calibration samples and therewith, log Koc of the test substance was determined from its measured capacity factor.
Chromatographic Conditions:
• HPLC Model No. :Agilent Technologies,1260 Infinity
• Flow Rate :1.0ml/min
• Column : ZORBAX Eclipse Plus C18,
4.6×100mm, 3.5 µm
• Mobile phase :Acetonitrile: water (55:45)
• Temperature :25°C
• Detector :Diode Array Detector @210nm
• Injector :Autosampler
• Injector volume :20µl
• Data Acquisition software :ChemStationOpen lab Control Panel

Key result

Sample No.:

#1

Type:

Koc

Value:

1.645 dimensionless

Temp.:

25 °C

Remarks on result:

other: 1.645 ± 0.003

Details on results (HPLC method):

PREPARATION PROCEDURE

2.2.1 Reagents:

a) Water: HPLC Grade
b) Acetonitrile: HPLC grade
2.2.2 Preparation of Reference substances:
The six reference substances, 2- Nitrobenzamide, p – Toluamide, 4 – methyl aniline, Aniline, N – methyl aniline, 2,5 Dichloroaniline were chosen having Koc value range from 1.45 to 2.58. Individual solutions of these six substances were prepared in Acetonitrile: water (55:45) with concentrations of 500 mg/l.
Urea (at concentration of 500 mg/l) was used as an unretained compound for the determination of the “dead time” t0.
K=tR -t0
t0

where k= capacity factor,
tR= retention time of test substance.
t0=retention time of Urea.
2.2.3 Preparation of Test Item:
A test item solution was prepared by accurately weighing 50mg of test item and diluted with mobile phase up to 100ml. Thus, the test solution concentration was 500mg/l. The pH of test substance was 6.24.

Reference substance	Log Koc	tR1	tR2	tR3	MeantR± S.D.	k	Log k
Urea	-	0.887	0.887	0.888	0.887±0.001	-	-
2-nitrobenzamide	1.45	1.091	1.094	-	1.092±0.002	0.231	-0.635
p-toluamide	1.78	1.18	1.182	-	1.181±0.001	0.331	-0.479
4-methylaniline(p-Tolouidine)	1.9	1.755	1.748	-	1.751±0.005	0.974	-0.011
Aniline	2.07	1.513	1.495	-	1.504±0.013	0.695	-0.157
N-methylaniline	2.28	2.303	2.294	-	2.298±0.006	1.591	0.201
2,5-Dichloroaniline	2.58	3.548	3.574	-	3.561±0.018	3.014	0.479

Test substance 2,2,2-trichloroethane-1,1-diol		K	Log k	Log Koc by Calibration Graph	Mean of LogKoc± S.D.
tR1	1.167	0.316	-0.501	1.647	1.645 ± 0.003
tR2	1.164	0.312	-0.505	1.643

Conclusions:

The Adsorption Coefficient of test substance 2,2,2-trichloroethane-1,1-diol (CAS No.302-17-0)was determined as per the HPLC method (OECD Guideline-121). The Log Koc value was found to be 1.645 ± 0.003 at 25°C

Executive summary:

The adsorption coefficient Koc in soil and in sewage sludge2,2,2-trichloroethane-1,1-diol (CAS No. 302-17-0)was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals. The reference substances were chosen according to structural similarity with the test substance and calibration graph was prepared. The reference substances were 2- Nitrobenzamide, p – Toluamide, 4 – methyl aniline, Aniline, N – methyl aniline, 2,5 Dichloroaniline having K_ocvalue ranging from 1.45 to 2.58. TheLog K_ocvalue was found to be1.645 ± 0.003 at 25°C.

This value indicates that the substance has low sorption to soil and sediment, moderate migration to ground water

Description of key information

The Adsorption Coefficient of test substance 2,2,2-trichloroethane-1,1-diol (CAS No.302-17-0)was determined as per the HPLC method (OECD Guideline-121). The Log Koc value was found to be 1.645 ± 0.003 (Koc=45.81) at 25°C.

Key value for chemical safety assessment

Koc at 20 °C:

45.081

Additional information

The adsorption coefficient Koc in soil and in sewage sludge2,2,2-trichloroethane-1,1-diol (CAS No. 302-17-0)was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals. The reference substances were chosen according to structural similarity with the test substance and calibration graph was prepared. The reference substances were 2- Nitrobenzamide, p – Toluamide, 4 – methyl aniline, Aniline, N – methyl aniline, 2,5 Dichloroaniline having K_ocvalue ranging from 1.45 to 2.58. TheLog K_ocvalue was found to be1.645 ± 0.003 at 25°C.

This value indicates that the substance has low sorption to soil and sediment, moderate migration to ground water

[LogKoc: 1.645]