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Environmental fate & pathways

Biodegradation in water and sediment: simulation tests

Administrative data

Endpoint:
biodegradation in water and sediment: simulation tests
Type of information:
other: applicants summary
Adequacy of study:
other information
Reliability:
other: Applicants summary
Rationale for reliability incl. deficiencies:
other: no reliability is given as this is an applicants summary entry

Data source

Referenceopen allclose all

Reference Type:
publication
Title:
Biotranformation of Organic in Soil Columns and an Infiltration Area
Author:
Bosma et al.
Year:
1996
Bibliographic source:
GROUND WATER, Vol. 34, No. 1, pp. 49-56, January-February
Reference Type:
review article or handbook
Title:
Microbial aspects of the behaviour of chlorinated compounds during soil passage
Author:
Bosma et al.
Year:
1990
Bibliographic source:
Org. Micropollut. Aquat. Environ. Proc. Eur. Supp., pp. 184-192
Reference Type:
publication
Title:
Persistent organic pollutants in river water and groundwater of the Netherlands
Author:
Zoeteman et al.
Year:
1980
Bibliographic source:
Chemosphere Vol. 9, pp. 231-249, Pergamon Press Ltd. 1980, Printed in Great Britain
Reference Type:
publication
Title:
Dechlorination of chlorobenzenes in anaerobic estuarine sediment
Author:
Masunaga S et al.
Bibliographic source:
Wat. Sci. Tech. Vol. 33, No. 6, pp. 173-180
Reference Type:
publication
Title:
Monoaromatics, chlorobenzenes and PCBs
Author:
Mackay et al.
Year:
1992
Bibliographic source:
Illustrated handbook of physical-chemical properties and environmental fate for organic chemicals I.; Lewis Publishers Inc., Baca Raton FL.
Reference Type:
secondary source
Title:
Canadian Water Quality Guidelines for Protection of Aquatic Life Chlorinated Benzenes 1,2,3 Trichchlorobenzene
Author:
Canadian Council of Ministers of the Environment
Year:
1999
Bibliographic source:
Canadian Council of Ministers of the Environment 1999 Exerpt from Publikation No. 1299, ISBN 1-896997-34-1

Materials and methods

Principles of method if other than guideline:
Applicants summary entry
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent

Results and discussion

Any other information on results incl. tables

Applicants summary entry:

Removal in sediment

Bosma et al. (1996)

Methanogenic conditions favoured the transformation of chlorinated substances by reductive dechlorination.1,2,3-trichlorobenzene was transformed > 90% (chlorobenzene, 1,3-dichlorobenzene) under methanogenic conditions. No removal observed under aerobic and denitrifying conditions. The study by Bosma et al. (1996) was performed as a column study using (small: 25 cm length and 5.5 cm internal diameter; large: 60 cm length and 11 cm internal diameter) and were wet packed with sediment from the River Rhine near Wageningen, or from the dune infiltration site of the Municipal Water Works of Amsterdam. The columns were percolated continuously at a flow rate of 1 cm/h in an upflow mode, with an mineral medium. Columns were operated under aerobic, denitrifying and methanogenic conditions.

 

Bosma et al. (1990)

Aerobic conditions turned out to be relatively unfavourable for biotransformation of the chlorinated compounds. Anaerobic conditions with a low redox-potential (sulphate or carbondioxide present as electron acceptor) are more applicable to degrade chlorinated compounds. Biotransformation of 1,2,3-trichlorobenzene under conditions with a low redox-potential (sulphate or carbondioxide present as electron acceptor) was observed.

Under aerobic (O2) und denitrifying (NO32-) conditions no biotransformation of 1,2,3-trichlorobenzene was observed (Bosma et al. 1990).

The tri- and dichlorobenzenes were transformed to monochlorobenzene (Bosma et al 1988). The process proceeded via reductive dechlorination.

 

Masunaga S et al. (1996)

The reductive dechlorination of chlorobenzenes in an anaerobic estuarine sediment was examined. Sediment slurry of Tsurumi river was spiked with the test compounds. The test tubes were placed in a constant temperature room at 25°C under anaerobic conditions.

The incubation lasted for a year. The extracted samples were analysed by GC/MS.

 

Initial slow transformation periods were observed. The overall loss of parent compound followed pseudo-first-order reaction kinetics. The observed rate constants estimated form the kinetic data.

t ½ = 23.2 day

k = 0.0299 day-1(first-order rate constant in test sediment)

ka = 0.0011 day-1(first-order rate constant in autoclaved sediment)

Detected intermediates: 1,3-dichlorobenzene > 1,2-dichlorobenzen, monochlorobenzene

 

Removal in surface water 

 

Zoeteman et al., 1980

The half-lives in rivers were estimated to be 1.9 day, 1.5 and 28 days based on monitoring data taken along the River Rhine. These half-lives differ considerably and are likely to be very inaccurate since only a limited number of samples were taken.

Mackay et al (1992) have modelled the environmental fate of chlorobenzenes.

In the aquatic environment, 1,2,3-trichloribenzen is found mostly in organic phases (organisms, sediments) or associated with suspended/ dissolved organic materials rather than dissolved in the water phase (log octanol-water partition coefficient 4.1) with half-lives of 6-18 weeks in the water and 1.1-3.4 years in the sediment.

Applicant's summary and conclusion