Naturally-Produced Organohalogens

1 General introduction and overview articles.- Evidence of naturally produced and man-made organohalogens in water and sediments.- The contribution of natural halogenation processes to the atmospheric halomethane burden.- Origin and occurrence of halogenated organic matter in soil.- AOX in groundwater.- 2 Characterization of organohalogens of natural origin.- Isolation of XAD-4 acids from natural waters and their importance as precursors to TOX and THM upon chlorination.- Natural AOX in the river Rhine: modelling and trace analysis.- Halogenated structural elements in naturally occurring organic matter.- Chemical characterization of organohalogens in a coniferous forest soil.- Chemical characterisation of adsorbable organic halogens (AOX) in precipitation.- Naturally produced organic chlorine in the Finnish aquatic environment.- 3 Natural production of organohalogens normally considered to be of anthropogenic origin.- Are polychlorinated biphenyls produced naturally ? Results from recent UK investigations.- Formation of organic chlorine compounds of low molecular weight in the chloroperoxidase-mediated reaction between chloride and humic material.- 4 Mechanisms for the incorporation of halogens into organic substances.- Incorporation of halogenated substances into humic material.- Detoxification of chlorophenols in soils by oxidative transformations on manganese and iron oxides.- On the possible role of humic materials in the environmental organohalogen budget: The enzymatically mediated incorporation of 4-chlorophenol into humic acids.- Reaction mechanism and 3-dimensional structure of bacterial non-haem haloperoxidases.- Structures of aquatic humic substances responsible for the reaction with chlorine.- Incorporation of haloalkanes into long chain fatty acids by the chloroalkane-degrading bacterium Rhodococcus rhodochrous NCIMB 13064.- Kinetic control of the biogeochemical formation of halogenated humic acids.- 5 Occurrence and production of organohalogens in the terrestrial environment.- The natural chlorinated plant hormone of pea, 4-chloroindole-3-acetic acid, an endogenous herbicide?.- Biosynthesis and metabolic role of chloromethane in fungi.- Occurrence of fluoroacetate, a naturally-produced organohalogen in plants.- Significant fungal biogenesis of physiologically important chlorinated aromatics in natural environments.- Naturally produced organohalogens: AOX-monitoring in plants and sediments.- Biosynthesis of fluoroacetate and 4-fluorothreonine by Streptomyces cattleya.- 6 Occurrence and production of organohalogens in the marine environment.- Marine phytoplankton as a natural source of volatile organohalogens.- Iodinated C1-C4 hydrocarbons released from ice algae in Antarctica.- Occurrence of halogenated fatty acids in bivalve lipids.- Formation and distribution of halogenated volatile organics in sea water.- The natural formation of trichloroethylene and perchloroethylene in sea water.- Occurrence of organic halogens in marine mammals.- Origin of organohalogens found in Baltic Sea sediments.- Bromoperoxidase from a marine red alga, Corallina pilulifera.- 7 Reactive chlorine and halogenated organic compounds in the atmosphere.- Inorganic Cl cycling in the marine boundary layer: a review.- Production of a photolytic precursor of atomic Cl from aerosols and Cl- in the presence of O3.- Biogenic emission of organobromine compounds to the Arctic Ocean and atmosphere.- Chlorinated C1- and C2-hydrocarbons in the needles of Scots Pine (Pinus sylvestris L.) in three forests of Northern Britain.- 8 Policy aspects.- From ‘is’ to‘ought’.- Occurrence and toxicology of natural and anthropogenic organohalogens and relevance to environmental protection.- What is the opinion of a policy-maker on naturally produced organohalogens? The governmental point of view.