Search results for "Chlorophenol"

The mutagenicity of MCPA and its soil metabolites, chlorinated phenols, catechols and some widely used slimicides in Finland

1977

Isolation and Characterization of Novosphingobium sp. Strain MT1, a Dominant Polychlorophenol-Degrading Strain in a Groundwater Bioremediation System

2002

ABSTRACT A high-rate fluidized-bed bioreactor has been treating polychlorophenol-contaminated groundwater in southern Finland at 5 to 8°C for over 6 years. We examined the microbial diversity of the bioreactor using three 16S ribosomal DNA (rDNA)-based methods: denaturing gradient gel electrophoresis, length heterogeneity-PCR analysis, and restriction fragment length polymorphism analysis. The molecular study revealed that the process was dependent on a stable bacterial community with low species diversity. The dominant organism, Novosphingobium sp. strain MT1, was isolated and characterized. Novosphingobium sp. strain MT1 degraded the main contaminants of the groundwater, 2,4,6-trichloroph…

Evidence for Natural Horizontal Transfer of the pcpB Gene in the Evolution of Polychlorophenol-Degrading Sphingomonads

2002

ABSTRACT The chlorophenol degradation pathway in Sphingobium chlorophenolicum is initiated by the pcpB gene product, pentachlorophenol-4-monooxygenase. The distribution of the gene was studied in a phylogenetically diverse group of polychlorophenol-degrading bacteria isolated from contaminated groundwater in Kärkölä, Finland. All the sphingomonads isolated were shown to share pcpB gene homologs with 98.9 to 100% sequence identity. The gene product was expressed when the strains were induced by 2,3,4,6-tetrachlorophenol. A comparative analysis of the 16S rDNA and pcpB gene trees suggested that a recent horizontal transfer of the pcpB gene was involved in the evolution of the catabolic pat…

Trends of organochlorine compounds in Finnish inland waters

2001

Caged common lake mussels (Anodonta piscinalis) have been used in the monitoring of organochlorine compounds in pulp and paper mill recipient watercourses of Finland annually from 1984 to 1998. Statistically significant decreasing trends of chlorophenols and chloroguaiacols originating from chlorobleaching were observed in all recipients in parallel with the decreasing discharges from the mills. Metabolites of chlorophenols, chloroanisoles and chloroveratroles had no or slightly increasing trends. Elevated PCB concentrations were measured in four watercourses. In two areas, PCBs were found to be significantly increasing, in two other cases they showed no trend. A mill producing recycled pap…

Heat shock protein Hsp70 expression and DNA damage in Baikalian sponges exposed to model pollutants and wastewater from Baikalsk Pulp and Paper Plant

2002

Abstract Lake Baikal, a unique habitat for a great number of endemic species, is the largest freshwater reservoir in the world which is still largely unaffected by anthropogenic pollution, except for some shore regions with industrial activity. The expressions of a biomarker of exposure (heat shock protein Hsp70) and a biomarker of effect (DNA single-strand breaks) were measured for the first time in endemic Baikalian sponge species (Baikalospongia intermedia, Lubomirskia fusifera, and Lubomirskia abietina). Tissue cubes of B. intermedia and dissociated cells of L. fusifera and L. abietina reacted to temperature stress (10–16 °C above ambient temperature) with a time-dependent increase in e…

Pentachlorophenol accumulation in the freshwater mussels Anodonta anatina and Pseudanodonta complanata, and some physiological consequences of labora…

1995

Freshwater mussels Anodanta anatina and Pseudanodonta complanata were exposed to (14C)-pentachlorophenol. The wet weight based bioconcentration factor (BCF = activity in animal per activity in water) at steady state varied from 80 to 120 for A. anatina and from 61 to 85 for P. complanata. The species did not differ significantly in their wet weight or lipid based BCFs but dry weight based values were significantly higher (40-50%) for A. anatina. The soft tissue dry weight and dry weight based condition index of A. anatina (Cl4 = soft tissue dry weight per shell length) differed significantly between natural mussel populations. In animals kept from 4 to 8 months in laboratory conditions, the…

The metabolism of phenol and substituted phenols in zebra fish.

1987

1. The metabolism of five phenols in zebra fish was studied after uptake from the medium. The results showed no qualitative differences to other Cyprinid fish species, only the oxidation rate seemed to be lower. 2. Phenyl glucuronide, phenyl sulphate, and quinol sulphate were identified as metabolites of phenol. 3. Identified metabolites of 2-cresol were 2-cresyl glucuronide, 2-cresyl sulphate, and 2-hydroxybenzoic acid in trace amounts. 4. Only the glucuronide and sulphate conjugates were detected as metabolites of 4-nitrophenol, 4-chlorophenol, and pentachlorophenol.

Induction of micronuclei in V79 Chinese hamster cells by tetrachlorohydroquinone, a metabolite of pentachlorophenol

1992

Tetrachlorohydroquinone, a metabolite of the fungicide pentachlorophenol, induced significant dose-related increases in micronuclei in V79 Chinese hamster cells without exogenous metabolic activation. The lowest observed effective dose was 10 microM, where the relative survival was about 62%. At the highest dose tested, 20 microM, the relative survival was about 8% and the frequency of cells with micronuclei was about 6 times the solvent control frequency. The induction of micronuclei by tetrachlorohydroquinone was significantly inhibited by the hydroxyl radical scavenger dimethyl sulfoxide at 5% (v/v).

New types of environmental POPs

1998

Recent knowledge on sources, biomagnification and ecotoxic potential of earlier less studied persistent organic pollutants (POP) is briefly reviewed. Chlorohydrocarbons discussed are techno‐chemicals polychloronaphthalenes (PCN), polychloroterphenyls (PCT), octachlorostyrene (OCS) and hexachlorobutadiene, pulp bleachery wastes chlorocymenes (CYMS), chlorocymenenes (CYMD), alkylpolychlorophenanthrenes (RPCPH), alkylprolychlorobibenzyls (RPCBB) and alkylpolychloronaphthalenes (RPCN), and fish contaminants polychlorofluorenes (PCFL) and fluorenones (PCFLO), alkyl polychlorofluorenes (RPCFL), polychlorodihydroanthracenes (PCDHA) and polychloroanthracenes (PCAN). Aromatic chloroethers discussed …

Microbial Adaptation to Boreal Saturated Subsurface: Implications in Bioremediation of Polychlorophenols

2008

Saturated subsurface environments pose challenges to the intrinsic microbiology. Prevailing environmental conditions (temperature, pH, bioavailability of substrates and nutrients) affect microbial biodegradation activity, which is often favored by certain redox conditions. Microbial adaptation in each redox environment proceeds by selection and enrichment of indigenous bacteria, evolution of novel catabolic pathways and horizontal gene transfer (Wilson et al. 1985; van der Meer et al. 1998; Tiirola et al. 2002b). Formation of biofilms enables microbial retainment, co-operation among microorganisms and enhanced gene transfer among organisms (Singh et al. 2006). Chlorophenols are toxic and pe…