α,α,α-trifluoro-p-toluidine

Adsorption / desorption

Administrative data

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Study not well described. No information on Koc, but only on sorption kinetic.

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Sediment-Associated Reactions of Aromatic Amines. 2. QSAR Development

Author:

Weber EJ, Colon D, Baughman GL

Year:

2002

Bibliographic source:

Environ. Sci. Technol.; 36; 11; 2443 - 2450.

Reference 2

Reference Type:

publication

Title:

Sediment-associated reactions of aromatic amines: QSAR development

Author:

Weber EJ; Colon D; Baughman GL

Year:

2000

Bibliographic source:

American Chemical Society, Division of Environmental Chemistry, 40(2), 642-645.

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 106 (Adsorption - Desorption Using a Batch Equilibrium Method)

Deviations:

not specified

GLP compliance:

not specified

Type of method:

other: no data

Media:

other: soil and sediment

Test material

Test material information

Constituent 1

Reference substance name:

α,α,α-trifluoro-p-toluidine

EC Number:

207-236-5

EC Name:

α,α,α-trifluoro-p-toluidine

Cas Number:

455-14-1

Molecular formula:

C7H6F3N

IUPAC Name:

4-(trifluoromethyl)aniline

Details on test material:

no data

Study design

Test temperature:

25°C

HPLC method

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: Gilson 305 gradient chromatographic pump equipped with an  Applied Biosystems 783 programmable wavelength detector, a Rheodyne 7161  injector (200 µL sample loop), an Alcott 728 autosampler, and a  Hewlett-Packard 3396A integrator.
- Type, material and dimension of analytical (guard) column: Water C18  µBondapack (300 mm long*3.9 mm i.d., 10 µm particle size). The columns  
were protected with an Alltech Applied Science Adsorbosphere C18

MOBILE PHASES
- Type: mixture of acetonitrile and a 5 mM phosphate buffer (pH 7)
DETERMINATION OF DEAD TIME: no data
REFERENCE SUBSTANCES: no data
DETERMINATION OF RETENTION TIMES: no data
REPETITIONS
- Number of determinations: 2
EVALUATION: no data

Batch equilibrium or other method

Analytical monitoring:

not specified

Details on sampling:

no data

Details on test conditions:

IDENTIFICATION AND QUANTIFICATION OF TEST SUBSTANCE/PRODUCT: no data
Details on sediment: - Details on collection: Sediment was collected from Cherokee Park (CP)  pond in Athens, GA.
- Textural classification: the percentages of sand, silt and clay in the  sediment were 36.54%, 32.09% and 31.37% respectively.
- Organic carbon (%): 3.3 +/- 0.5%
- Bulk density (g/cm³): particle density was 2.41 g/cm3.

TEST CONDITIONS - Suspended solids concentration: 5%
- pH: 5.5

TEST SYSTEM
- Type, size and further details on reaction vessel: 250 ml Erlenmeyer  flask
- Water filtered: yes through Nylon 66 0.2µm filter
- Number of reaction vessels/concentration: no data
- Other: The air-dried pond sediment, double distilled water, and a 250  ml Erlenmeyer flask were heat sterilized (1*20 min, 121°C, 20 psi). Using  
sterile techniques, 95 ml of H2O was added to 5 g of sediment in the 250  ml Erlenmeyer flask. The appropriate concentration of an aqueous stock  
solution of the substituted aniline, which had been sterilized by  filtering through a Nylon 66 0.2µm filter, was introduced with a sterile,  disposable 1 ml pipette. The flask was placed on a temperature-controlled  platform shaker at 25°C. At pre-selected times, a 3 ml aliquot was  removed while 
stirring using sterile techniques. The aliquot was  transferred to two 1.5 ml polypropylene centrifuge tubes and centrifuged  for 10 min at 14000 
rpm. The supernatant was removed and transferred to  glass autosample vials for LC analysis.
- Duration of adsorption equilibration at given conditions: no data

Computational methods:

no data

Results and discussion

Results: HPLC method

Details on results (HPLC method):

Generally, the sorption kinetics of the substitued anilines were  characterized by a rapid, initial loss of substrate from the aqueous  phase followed by a much slower rate of disappearance. The initial rates  of sorption varied with the type and position of the substituent group.  Sorption rate 
constants were correlated with molecular descriptors  including ionization constants (pka's), HOMO energies, E1 and E2  oxidation potentials, and 
Hammett contants. Based on the strength of  linear correlations and the availability of data, ionization constants  appear to be the most useful 
molecular desciptor for predicting initial  rates of sorption of substituted anilines in natural soils and sediments. k1 (rate constant for fast, initial 
sorption): 2.7*10-2 (1/h) k2 (rate constant for slow sorption): 1.37*10-2 (1/h) pKa (ionization constant): 2.54 E1 (ionization potential): 0.922 (V)
HOMO (energy): -8.79 (eV)

Applicant's summary and conclusion

Validity criteria fulfilled:

not specified

Remarks:

OECD 106 is followed but no Koc is derived

Conclusions:

The study reported kinetic results about the adsorption of p-TFMA on sediment but no information is given on Koc values