(Z)-4-[C11-13 (branched) alkylamino]-4-oxo-2-butenoic acid

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:

other: GLP compliant 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))

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Radiolabelling:

no

Test temperature:

23°C

Details on study design: HPLC method:

Measuring parameters for both pH values 2.1 and 7
Column: Prontosil 120-5-CN, 250 x 3 mm, 5 µm (BISCHOFF)
Mobile phase: pH 2.1: 1000 ml Water + 1 ml H3PO4 (pH 2.1)/ acetonitrile 65:35 (v/v)
pH 7: 0.050 M K2HPO4 Buffer pH7/Acetonitrile 9:1 (v/v)
Flow rate: 0.7 ml/min
lnjection volume: 5 µI
Temperature: 23 °C
Detector: UV/Vis, λ= 205 nm
Dead time: The dead time of the HPLC-system was measured with formamide.

Sample No.:

#1

Type:

log Koc

Value:

2 - <= 3.5 dimensionless

pH:

7

Temp.:

23 °C

Sample No.:

#2

Type:

log Koc

Value:

2.7 - <= 5 dimensionless

pH:

2.1

Temp.:

23 °C

Details on results (HPLC method):

- Retention times of reference substances used for calibration:

see table 1 reference compounds for pH 2.1 in any other infromation incl. tables
see table 2 reference compounds for pH 7 in any other infromation incl. tables


- Details of fitted regression line (log k' vs. log Koc):

Details for pH 2.1

The retention time of the reference substances determined by means of the above mentioned HPLC separation is converted into the corresponding k' value:
k'=( tr - to)/to
k' = capacity factor
tr = retention time of the corresponding substance t0 = dead time (measured with formamide)

The calibration is performed with reference substances of known Koc. The plot of log k' as a function of log Koc is used for the determination of the Koc of the test item:
log Koc = 4.3089 log k' + 3.0791


At pH 2.1 (pH of the water used for the preparation of the eluent): yielded log Koc values in the range from Koc = 2.7 to 5.0 at T = 23 °C.


Details for pH 7

The retention time of the reference substances determined by means of the above mentioned HPLC separation is converted into the corresponding k' value:

k'=(tr - to)/ to


k' = capacity factor
tr = retention time of the corresponding substance t0 = dead time (measured with formamide)

The calibration is performed with reference substances of known Koc- The plot of log k' as a function of log Koc is used for the determination of the Koc of the test item:
log Koc = 1.6905 log k' + 2.1091

At pH 7 (pH of the buffer used for eluent): yielded log Koc values in the range from Koc = 2.0 to 3.5

Table 1: reference compounds for pH 2.1

Compound	tR / min*	k'	log k'	log Koc
Formamide	2.2
Methylbenzoate	3.4	0.50	-0.301	1.80
2,5-Dichloraniline	3.8	0.71	-0.151	2.55
Naphthalene	4.3	0.92	-0.037	2.75
1,2,3-Trichlorbenzene	4.6	1.04	0.017	3.16
Pyrazophos	5.5	1.44	0.159	3.65
Phenanthrene	5.6	1.50	0.178	4.09
Diclofop-methyl	6.8	2.03	0.307	4.20
DDT	10.5	3.72	0.570	5.63
Testitem Start	4.0	0.79	-0.100	2.65
Test item 1.Peak	4.3	0.92	-0.039	2.91
Test item 2.Peak	4.7	1.09	0.036	3.23
Testitem 3.Peak	5.2	1.33	0.125	3.62
Testitem 4.Peak	5.8	1.61	0.207	3.97
Testitem 5.Peak	6.5	1.92	0.284	4.30
Testitem End	8.4	2.76	0.440	4.98

 

Table 2: reference compounds for pH 7

Compound	Imin	k'	log k'	log Koc
Formamide	2.3
Acetanilide	3.7	0.57	-0.241	1.25
2-Nitrobenzamide	3.1	0.31	-0.515	1.45
N,N-Dimethylbenzamide	4.0	0.73	-0.139	1.52
Methylbenzoate	4.9	1.08	0.034	1.80
4-Nitrobenzamide	3.2	0.39	-0.414	1.93
Carbendazim	4.9	1.10	0.042	2.35
2,5-Dichloraniline	5.7	1.43	0.156	2.55
Naphthalene	8.4	2.58	0.412	2.75
Phenylbenzoate	12.3	4.24	0.627	2.87
1,2,3-Trichlorbenzene	9.8	3.18	0.502	3.16
Phenanthrene	27.2	10.61	1.026	4.09
Test item Start	4.4	0.89	-0.050	2.03
Testitem 1.Peak	5.5	1.37	0.135	2.34
Test item 2.Peak	8.4	2.60	0.414	2.81
Test item 3.Peak	11.5	3.89	0.590	3.11
Test item End	18.6	6.93	0.841	3.53

 

Validity criteria fulfilled:

yes

Conclusions:

Adsoption to solid phase is expected.

Executive summary:

Although the test item was found to be surface active, the HPLC method was applied and yielded:

pH 7 (pH of the buffer used for the preparation of the eluent): yielded log Koc = 2.0 to 3.5

pH 2.1 (pH of the water used for the preparation of the eluent): yielded log Koc = 2.7 to 5.0

both at T = 23°C.

Description of key information

Adsorption to solid soil phase is expected.

pH 7 (pH of the buffer used for the preparation of the eluent): yielded log Koc = 2.0 to 3.5

pH 2.1 (pH of the water used for the preparation of the eluent): yielded log Koc = 2.7 to 5.0

both at T = 23 °C.

Additional information

The adsorption potential of the test substance has been examined in a GLP guideline study according to OECD 121 [BASF SE 2013]. In this study, the logKOC has been determined experimentally by an HPLC screening method.

The adsorption coefficient of the test item found depends on the pH applied. As the test item consists of a large number of components with different logKoc values, only a range for logKoc can be given:

pH7 (pH of the buffer used for eluent): yielded logKoc values in the range from Koc = 2.0 to 3.5 at 23°C

pH2.1 (pH of the buffer used for eluent): yielded logKoc values in the range from Koc = 2.7 to 5.0 at 23°C