Hexachloroacetone

Hydrolysis

Administrative data

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

1987

Materials and methods

Principles of method if other than guideline:

Hydrolyses at different pH buffer and temperature followed by a gas liquid chromatograph analysis with ECD

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Hexachloroacetone

EC Number:

204-129-5

EC Name:

Hexachloroacetone

Cas Number:

116-16-5

Molecular formula:

C3Cl6O

IUPAC Name:

hexachloropropan-2-one

Test material form:

not specified

Details on test material:

The chemical hexachloroacetone (HCA), were purchased from Tokyo-Kasei Co. Tokyo of Japan.
In the first experiment, 4 kinds of buffer solutions which had pH 4.0 (0.2M, acetate), pH 6.0 and 7.0 (0.2M, phosphate), and pH 8.0 (0.2 M, Tris-HCl) were used as test solutions.
In the second experiment, sea water (pH 8.0, COD= 1.0 mg/L), effluents A (pH 4.3, COD= 148.3 mg/L) and B (pH 6.1, COD= 49.4 mg/L) from a kraft pulp mill were employed for test solutions.

Radiolabelling:

no

Study design

Buffers:

4 kinds of buffer solutions which had pH 4.0 (0.2M, acetate), pH 6.0 and 7.0 (0.2M, phosphate), and pH 8.0 (0.2 M, Tris-HCl) were used as test solutions.

Details on test conditions:

A dioxane solution of HCA was mixed with a 5 ml of test solution in each test tube and kept for 0 - 48 h. After an appropriate time, 5 ml of n-hexane for HCA followed by 2 g of NaCl were added and the residual chloroacetone was extracted by repeating 8 times of 30 sec shaking. An extract was diluted with the same solvent to an appropriate concentration and was analyzed by a gas-liquid chromatograph equipped with an electron capture detector. The running conditions were as follows:
instrument, Shimadzu GC-4CM; column, 2% silicone OV-17 (id 2mm x 2m); column temperature 120°C (HCA); injection and detector temperature, 210°C; carrier gas, N2, 40 mL/min.
The retention times HCA were 2.9 min, 5.4 min and 4.0 min, respectively. The content of hexachloroacetone was calculated from the calibration curve.
These experiments were done in the dark (shielding light with an aluminum foil) or under the sun-lamp (270-440 nm, max 320 nm) at different temperatures (0°C, 15°C, 40°C). The extraction efficiency of each organic solvent to hexachloroacetone was 95 ±2% in the preliminary experiment.

Duration of test

Duration:

48 h

Initial conc. measured:

10 mmol/L

Results and discussion

Details on results:

Extraction sufficiency was 95 +-2 %

Any other information on results incl. tables

HCA was extremely unstable compound even in the acidic conditions. It entirely disappeared within 6 h except the reaction at pH 4.0 (0°C). The residual ratio of HCA in the solution (pH 4.0, 0°C) was 70%after 24 h. The photo-irradiation also accelerated the degradation ratio of HCA. In this experiment, dioxane was used as a solvent because of the lability of HCA in an acetone solution. The similar solvent interaction of HCA was also observed by other investigators.

It was found that the degradation ratio of the chloroacetone which show mutagenic activity was depend upon the reaction pH and temperature, but not so much on the light. It was also found that the increase of the number of chlorine atoms in the molecule cause the decrease of the stability of the chloroacetone.

In the second experiment, the degradation efficiency of the chloroacetone was examined in the environmental samples such as coastal sea water (pH 8.0), kraft pulp mill effluents A (pH 4.3) and B (pH 6.1) in the dark. HCA disappeared immediately during the incubation in sea water. HCA was very fragile and it disappeared within 2 h in three water samples. The degradation of HCA in the environmental samples was consistent with that observed in buffer solutions. These results are compatible with a report in which 2-chloropropenal in acidic solution is more stable than in a basic solution.