Registration Dossier

Administrative data

Endpoint:
toxicity to soil microorganisms
Type of information:
other: BUA report
Adequacy of study:
other information
Reliability:
other: BUA report
Rationale for reliability incl. deficiencies:
other: BUA report

Data source

Referenceopen allclose all

Reference Type:
other: BUA Report
Title:
Unnamed
Year:
1991
Reference Type:
publication
Title:
Inhibition of nitrification and denitrification in calcareous chernozem soil
Author:
Kostov O
Year:
1975
Bibliographic source:
Soil Biol. Conserv. Biosphere [Proc. Meet.] 7, 151-155
Reference Type:
publication
Title:
Unnamed
Year:
1968
Reference Type:
publication
Title:
Untersuchungen ueber die Hemmung der Nitrifikation durch einige chemische Praeparate [in German]
Author:
Ansorge H, Markert S, Jauert R
Year:
1967
Bibliographic source:
Albrecht-Thaer-Archiv Berlin, Band 11, 509-516
Reference Type:
publication
Title:
Effect of chemical structure of phenylureas and anilines on the denitrification process
Author:
Bollag JM, Nash CL
Year:
1974
Bibliographic source:
Bull. Environ. Contam. Toxicol. 12, 241-248
Reference Type:
publication
Title:
Microbial mineralization of ring-substituted anilines through an ortho-cleavage pathway
Author:
Zeyer J, Wasserfallen A, Timmis KN
Year:
1985
Bibliographic source:
Appl. Environ. Microbiol. 50, 447-453
Reference Type:
publication
Title:
Microbial degradation of para-chloroanilines as sole carbon and nitrogen source
Author:
Zeyer J, Kearney PC
Year:
1982
Bibliographic source:
Pesticide Biochemistry and Physiology 17, 215-223

Materials and methods

Principles of method if other than guideline:
BUA report
GLP compliance:
not specified

Test material

Constituent 1
Chemical structure
Reference substance name:
2-chloroaniline
EC Number:
202-426-4
EC Name:
2-chloroaniline
Cas Number:
95-51-2
Molecular formula:
C6H6ClN
IUPAC Name:
2-chloroaniline

Results and discussion

Any other information on results incl. tables

BUA report:

Several studies on the toxicity of 2-chloroaniline to soil microorganisms were summarized in the assessment of the BUA report 57 (2001). Some of these studies were reliable studies with restrictions, not reliable or reliability was not assignable because references were only cited as secondary literature.

Under anaerobic conditions o-chloroaniline initially inhibited the biological activity of the soil (microbial CO2 production) in concentrations of 2.5% and 5%, respectively, of the applied nitrogen fertilizer. During incubation time, this inhibition got weaker and turned in the lower concentration with the beginning of Day 5 into a stimulation of the soil activity.

o-Chloroaniline caused at 100 mg/kg and 50% of the maximum water holding capacity during the first 2 weeks of incubation a decrease of the total bacteria cell count. At all later investigation dates and at concentrations of 5, 10 and 50 mg/kg no negative impact on the total bacteria cell count could be detected during the observation period (in sum 12 weeks). At all 4 concentrations (5, 10, 50, and 100 mg/kg) o-chloroaniline stimulated the fungal cell count.

The cell proliferation of a bacterial strain of Moraxella sp. isolated from a soil was inhibited during the exponential growth period by about 50% by a o-chloroaniline concentration of 128 mg/L.

The nitrification in different soils was inhibited after 8 weeks of incubation with o-chloroaniline beginning at concentrations of 4 mg/kg or 2 mg/kg, respectively, depending on the soil type (each at 60% of the maximum water holding capacity). 50% inhibition was reported at concentrations of >50 mg o-chloroaniline/kg (Ansorge et al. 1967). At o-chloroaniline concentrations below the inhibition limit the nitrification was stimulated slightly. It could be shown that o-chloroaniline inhibited the reproduction of the nitrificants.

On the one hand, o-chloroaniline inhibited in a soil sample under anaerobic conditions the denitrification and - to a minor degree - the reproduction of the nitrificants. On the other hand, o-chloroaniline did not inhibit the denitrification of an isolated soil bacterium which reduces NO3- only up to NO2.

Applicant's summary and conclusion