Atmospheric Degradation of Organic Substances – Data for Persistence and Long–range Transport Potential

Prof. Dr. Walter Klopffer studied chemistry at the Karl-Franzens-University in Graz, Austria. He then joined the Battelle Institute in Frankfurt/Main, Germany, and since 1975 he is also Professor for Physical Chemistry at the University of Mainz. Dr. Klopffer's main fields of interest include the spectroscopy and photophysics of aromatic polymers, and the environmental assessment of chemicals (persistence, abiotic degradation) and products (Life Cycle Assessment). Dr. Burkhard Wagner obtained a PhD in Chemistry from the University of Heidelberg, Germany. He completed a postdoctoral period at the California Institute of Technology with George Hammond before joining the German Federal Environmental Agency (Umweltbundesamt), where he was the long-time section head for environmental impact assessment of chemicals.

Foreword.Preface.Chapter 1 Significance of Photo-degradation in Environmental Risk Assessment.1 Introduction.2 Persistence and Long-range Transport Potential in Chemicals Regulation.3 Multimedia Models as Tools to Estimate Persistence and Long-range Transport Potential.4 Data Requirements for Multimedia Models.5 Estimation of the Rate Constant of Organic Substances with Hydroxyl Radicals.6 Research Requirements for Photo-degradation of Semi-volatile Substances.7 Conclusions.References.Chapter 2 Abiotic Degradation in the Atmosphere.1 Introduction.2 Photo-degradation in the Homogenous Gas Phase of the Troposphere.2.1 Indirect Photochemical Reactions.2.1.1 The Reaction with OH-Radicals.2.1.1.1 Sources and Sinks of the OH-Radical.2.1.1.2 Reactions of OH with Organic Compounds.2.1.2 The Reaction with NO3-Radicals.2.1.2.1 Sources and Sinks of the NO3-Radical.2.1.2.2 Reactions of NO3 with Organic Compounds.2.1.3 The Reaction with Ozone.2.1.3.1 Sources and Sinks of O3 in the Troposphere.2.1.3.2 Reactions of O3 with Organic Compounds.2.2 Direct Photochemical Reactions.2.2.1 Quantum Efficiency.2.2.2 Examples of Photochemical Reactions in the Gas Phase.3 Heterogeneous Degradation.3.1 Degradation on Solid Surfaces.3.1.1 Introduction.3.1.2 Degradation on Fly Ash and Soot.3.1.3 Degradation on Artificial Aerosols.3.2 Degradation in Droplets.3.2.1 Direct Photochemical Transformation.3.2.2 Reactive Trace Compounds in Cloud, Fog and Rainwater.3.2.3 Reactions of Organic Molecules.3.2.4 Summary.4 Experimental.4.1 Indirect Photochemical Degradation.4.1.1 Bimolecular Reaction with OH.4.1.1.1 Direct Methods for Measuring kOH.4.1.1.2 Indirect Methods for the Measurement of kOH.4.1.2 Bimolecular Reaction with NO3.4.1.2.1 Introduction.4.1.2.2 Absolute Measurement.4.1.2.3 Relative Measurements.4.1.3 Bimolecular Reaction with Ozone.4.2 Direct Photo-transformation.4.2.1 Determination of the Quantum Efficiency in the Gas Phase.4.2.1.1 Gas Cuvette and Monochromatic Radiation.4.2.1.2 Smog-chamber Method.4.2.2 Outlook.4.3 Degradation in the Adsorbed State.4.3.1 Introduction.4.3.2 Aerosol Chambers.4.3.3 Alternative Measurements of kOH,ads.5 Additional Information Necessary for Calculating Lifetimes.5.1 Atmospheric Lifetimes.5.2 Indirect Photochemical Degradation.5.2.1 Average OH Concentration in the Troposphere.5.2.2 Average NO3 Concentration in the Troposphere.5.2.3 Average O3 Concentration in the Troposphere.5.3 Direct Photochemical Degradation.5.3.1 Introduction.5.3.2 Absorption Spectrum.5.3.3 Spectral Photon Irradiance.5.3.4 Final Comments on Direct and Indirect Photochemical Transformation.References.Chapter 3 Table of Reaction Rate Constants of Photo-Degradation Processes.1 Content of the Table.2 Explanation of the Column Headings.3 Content of the Footnotes.4 Completeness and Accuracy.5 Atmospheric Half-lives.6 Selection of Substances.7 Quality Index (QI).8 Temperature Dependence of the Rate Constant.9 Pressure Dependence of the Rate Constant.10 Direct Photolysis.Table: Reaction Rate Constants and Quantum Efficiencies for Atmospheric Photo-degradation of Chemicals.Footnotes to the Table.References to the Table.Appendix: CAS Register.Subject Index.