ENVIRONMENTAL CHEMISTRY

(1)

(2)

ENVIRONMENTAL CHEMISTRY

NINTH EDITION

(3)

(4)

ENVIRONMENTAL CHEMISTRY

NINTH EDITION

STANLEY E. MANAHAN

CRC Press is an imprint of the

Taylor & Francis Group, an informa business Boca Raton London New York

(5)

The cover illustration depicts the pathway of solar energy captured by photosynthesis to convert atmospheric carbon dioxide to biomass that can be used as a feedstock for the thermochemical production of methane. This synthetic natural gas product is the cleanest burning of all the carbon-based fuels. Methane made by the biomass pathway is neutral with respect to the production of greenhouse gas carbon dioxide because any of that gas generated by combustion of biomass-based synthetic natural gas was removed from the atmosphere by photosynthesis in producing the biomass feedstock. Biomass-based synthetic fuel production and other sustainable energy technologies are discussed in detail in Chapter 19, “Sustainable Energy: The Key to Everything.”

CRC Press

Taylor & Francis Group

6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742

CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works

Printed in the United States of America on acid-free paper 10 9 8 7 6 5 4 3 2 1

International Standard Book Number: 978-1-4200-5920-5 (Hardback)

This book contains information obtained from authentic and highly regarded sources. Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the valid- ity of all materials or the consequences of their use. The authors and publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint.

Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or uti- lized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopy- ing, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers.

For permission to photocopy or use material electronically from this work, please access www.copyright.com (http://

www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that provides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged.

Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe.

Library of Congress Cataloging-in-Publication Data Manahan, Stanley E.

Environmental chemistry / Stanley E. Manahan. -- 9th ed.

p. cm.

Includes bibliographical references and index.

ISBN 978-1-4200-5920-5 (hardcover : alk. paper) 1. Environmental chemistry. I. Title.

TD193.M36 2010

628--dc22 2009040939

Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com

(6)

v

Chapter Environmental Biochemistry ... 609 22.1 Biochemistry ... 609 22.1.1 Biomolecules ... 609 22.2 Biochemistry and the Cell ... 610 22.2.1 Major Cell Features ... 610 22.3 Proteins ... 611 22.3.1 Protein Structure ... 613 22.3.2 Denaturation of Proteins ... 614 22.4 Carbohydrates ... 614 22.5 Lipids ... 616 22.6 Enzymes ... 618 22.7 Nucleic Acids ... 620 22.7.1 Nucleic Acids in Protein Synthesis ... 623 22.7.2 Modifi ed DNA ... 623 22.8 Recombinant DNA and Genetic Engineering ... 623 22.9 Metabolic Processes ... 624 22.9.1 Energy-Yielding Processes ... 624 22.10 Metabolism of Xenobiotic Compounds ... 625 22.10.1 Phase I and Phase II Reactions ... 625 Literature Cited ... 626 Supplementary References ... 626 Questions and Problems ... 626 23

Chapter Toxicological Chemistry ... 629 23.1 Introduction to Toxicology and Toxicological Chemistry ... 629 23.1.1 Toxicology ... 629 23.1.2 Synergism, Potentiation, and Antagonism ... 631 23.2 Dose–Response Relationships ... 631 23.3 Relative Toxicities ... 632 23.3.1 Nonlethal Effects ... 632 23.4 Reversibility and Sensitivity ... 634 23.4.1 Hypersensitivity and Hyposensitivity ... 634 23.5 Xenobiotic and Endogenous Substances ... 634 23.6 Toxicological Chemistry ... 635 23.6.1 Toxicological Chemistry Defi ned ... 635 23.6.2 Toxicants in the Body ... 635 23.6.2.1 Phase I Reactions ... 635 23.6.2.2 Phase II Reactions ... 636 23.7 Kinetic Phase and Dynamic Phase ... 637 23.7.1 Kinetic Phase ... 637 23.7.2 Dynamic Phase ... 637 23.7.2.1 Primary Reaction in the Dynamic Phase ... 637 23.7.2.2 Biochemical Effects in the Dynamic Phase ... 638 23.7.2.3 Responses to Toxicants ... 639

(23)

xxii Contents 23.8 Teratogenesis, Mutagenesis, Carcinogenesis, and Effects

On the Immune and Reproductive Systems ... 639 23.8.1 Teratogenesis ... 639 23.8.2 Mutagenesis ... 639 23.8.2.1 Biochemistry of Mutagenesis ... 640 23.8.3 Carcinogenesis ... 641 23.8.3.1 Biochemistry of Carcinogenesis ... 642 23.8.3.2 Alkylating Agents in Carcinogenesis ... 642 23.8.4 Testing for Carcinogens ... 643 23.8.4.1 Bruce Ames Test ... 644 23.8.5 Immune System Response ... 644 23.8.6 Endocrine Disruption ... 644 23.9 Health Hazards ... 644 23.9.1 Assessment of Potential Exposure ... 645 23.9.2 Epidemiological Evidence ... 645 23.9.3 Estimation of Health Effects Risks ... 646 23.9.4 Risk Assessment ... 646 Literature Cited ... 646 Supplementary References ... 646 Questions and Problems ... 647 24

Chapter Toxicological Chemistry of Chemical Substances ... 649 24.1 Introduction ... 649 24.1.1 ATSDR Toxicological Profi les ... 649 24.2 Toxic Elements and Elemental Forms ... 649 24.2.1 Ozone ... 649 24.2.2 White Phosphorus ... 651 24.2.3 Elemental Halogens ... 651 24.2.4 Heavy Metals ... 651 24.3 Toxic Inorganic Compounds ... 652 24.3.1 Cyanide ... 652 24.3.2 Carbon Monoxide ... 652 24.3.3 Nitrogen Oxides ... 653 24.3.4 Hydrogen Halides ... 653 24.3.4.1 Hydrogen Fluoride ... 653 24.3.4.2 Hydrogen Chloride ... 654 24.3.5 Interhalogen Compounds and Halogen Oxides ... 654 24.3.6 Inorganic Compounds of Silicon ... 654 24.3.7 Asbestos ... 655 24.3.8 Inorganic Phosphorus Compounds ... 655 24.3.9 Inorganic Compounds of Sulfur ... 655 24.3.10 Perchlorate ... 656 24.3.11 Organometallic Compounds ... 656 24.3.11.1 Organolead Compounds ... 656 24.3.11.2 Organotin Compounds ... 657 24.3.11.3 Carbonyls ... 657 24.3.11.4 Reaction Products of Organometallic Compounds ... 657 24.4 Toxicology of Organic Compounds ... 657 24.4.1 Alkane Hydrocarbons ... 657 24.4.2 Alkene and Alkyne Hydrocarbons ... 658

(24)

Contents xxiii 24.4.3 Benzene and Aromatic Hydrocarbons ... 658 24.4.3.1 Toluene ... 659 24.4.3.2 Naphthalene ... 659 24.4.3.3 Polycyclic Aromatic Hydrocarbons ... 659 24.4.4 Oxygen-Containing Organic Compounds ... 660 24.4.4.1 Oxides ... 660 24.4.4.2 Alcohols ... 660 24.4.5 Phenols ... 661 24.4.5.1 Aldehydes and Ketones ... 661 24.4.5.2 Carboxylic Acids ... 662 24.4.5.3 Ethers ... 662 24.4.5.4 Acid Anhydrides ... 662 24.4.5.5 Esters ... 662 24.4.6 Organonitrogen Compounds ... 663 24.4.6.1 Aliphatic Amines ... 663 24.4.6.2 Carbocyclic Aromatic Amines ... 664 24.4.6.3 Pyridine ... 664 24.4.6.4 Acrylamide: Toxic Potato Chips? ... 664 24.4.6.5 Nitriles ... 665 24.4.6.6 Nitro Compounds ... 665 24.4.6.7 Nitrosamines ... 665 24.4.6.8 Isocyanates and Methyl Isocyanate ... 665 24.4.6.9 Organonitrogen Pesticides ... 665 24.4.7 Organohalide Compounds ... 666 24.4.7.1 Alkyl Halides ... 666 24.4.7.2 Alkenyl Halides ... 667 24.4.7.3 Aryl Halides ... 667 24.4.8 Organohalide Pesticides ... 668 24.4.8.1 TCDD ... 668 24.4.8.2 Chlorinated Phenols ... 669 24.4.9 Organosulfur Compounds ... 669 24.4.9.1 Sulfur Mustards ... 669 24.4.10 Organophosphorus Compounds ... 670 24.4.10.1 Organophosphate Esters ... 670 24.4.10.2 Phosphorothionate and Phosphorodithioate

Ester Insecticides ... 670 24.4.10.3 Organophosphorus Military Poisons ... 671 24.5 Toxic Natural Products ... 671 Literature Cited ... 672 Supplementary References ... 672 Questions and Problems ... 673 25

Chapter Chemical Analysis of Water and Wastewater ... 677 25.1 General Aspects of Environmental Chemical Analysis ... 677 25.1.1 Error and Quality Control ... 677 25.1.2 Water Analysis Methods ... 678 25.2 Classical Methods ... 678 25.3 Spectrophotometric Methods ... 679 25.3.1 Absorption Spectrophotometry ... 679 25.3.2 Atomic Absorption and Emission Analyses ... 680 25.3.3 Atomic Emission Techniques ... 682

(25)

xxiv Contents 25.4 Electrochemical Methods of Analysis ... 682 25.5 Chromatography ... 683 25.5.1 High-Performance Liquid Chromatography ... 685 25.5.2 Chromatographic Analysis of Water Pollutants ... 686 25.5.3 Ion Chromatography ... 686 25.6 Mass Spectrometry ... 686 25.7 Analysis of Water Samples ... 687 25.7.1 Physical Properties Measured in Water ... 687 25.7.2 Water Sampling ... 687 25.7.2.1 Extractors ... 688 25.7.3 Water Sample Preservation ... 689 25.7.4 Total Organic Carbon in Water ... 689 25.7.5 Measurement of Radioactivity in Water ... 690 25.7.6 Biological Toxins ... 690 25.7.7 Summary of Water Analysis Procedures ... 690 25.8 Automated Water Analyses ... 692 25.9 Speciation ... 692 25.10 Emerging Contaminants in Water Analysis ... 693 25.11 Chiral Contaminants ... 694 Literature Cited ... 695 Supplementary References ... 695 Questions and Problems ... 696 26

Chapter Analysis of Wastes and Solids ... 697 26.1 Introduction ... 697 26.2 Sample Digestion for Elemental Analysis ... 698 26.3 Analyte Isolation for Organics Analysis ... 698 26.3.1 Solvent Extraction ... 698 26.3.2 Supercritical Fluid Extraction ... 699 26.3.3 Pressurized Liquid Extraction and Subcritical

Water Extraction ... 699 26.4 Sample Cleanup ... 700 26.5 Sample Preparation for VOCs ... 701 26.6 Bioassay and Immunoassay Screening of Wastes ... 702 26.7 Determination of Chelating Agents ... 702 26.8 Toxicity Characteristic Leaching Procedure ... 703 Literature Cited ... 704 Supplementary References ... 704 Questions and Problems ... 705 27

Chapter Analysis of the Atmosphere and Air Pollutants ... 707 27.1 Atmospheric Monitoring ... 707 27.1.1 Air Pollutants Measured ... 707 27.2 Sampling ... 708 27.3 Methods of Analysis ... 709 27.4 Determination of Sulfur Dioxide ... 710 27.5 Nitrogen Oxides ... 711 27.6 Analysis of Oxidants ... 712

(26)

Contents xxv 27.7 Analysis of Carbon Monoxide ... 713 27.8 Determination of Hydrocarbons and Organics ... 714 27.8.1 Determination of Specifi c Organics in the Atmosphere ... 714 27.9 Analysis of Particulate Matter ... 714 27.9.1 Filtration ... 714 27.9.2 Collection by Impactors ... 716 27.9.3 Particle Analysis ... 716 27.9.4 X-Ray Fluorescence ... 716 27.9.5 Determination of Lead in Particulate Matter ... 717 27.10 Direct Spectrophotometric Analysis of Gaseous Air Pollutants ... 718 Literature Cited ... 719 Supplementary References ... 720 Questions and Problems ... 720 28

Chapter Analysis of Biological Materials and Xenobiotics ... 723 28.1 Introduction ... 723 28.2 Indicators of Exposure to Xenobiotics ... 723 28.3 Determination of Metals ... 725 28.3.1 Direct Analysis of Metals ... 725 28.3.2 Metals in Wet-Ashed Blood and Urine ... 725 28.3.3 Extraction of Metals for Atomic Absorption Analysis ... 725 28.4 Determination of Nonmetals and Inorganic Compounds ... 726 28.5 Determination of Parent Organic Compounds ... 726 28.6 Measurement of Phase I and Phase II Reaction Products ... 727 28.6.1 Phase I Reaction Products ... 727 28.6.2 Phase II Reaction Products ... 728 28.6.3 Mercapturates ... 729 28.7 Determination of Adducts ... 729 28.8 The Promise of Immunological Methods ... 730 Literature Cited ... 732 Supplementary References ... 732 Questions and Problems ... 733 Index ... 735

(27)

(28)

xxvii

Preface

Environmental Chemistry, ninth edition, maintains much the same organizational structure, level, and emphasis that have been developed through preceding editions, with updates in keeping with the emerging face of the dynamic science of environmental chemistry. Therefore, rather than entering into an immediate discussion of a specifi c environmental problem, such as stratospheric ozone depletion, the book systematically develops the concept of environmental chemistry so that, when specifi c pollution problems are discussed, the reader has the background to understand such problems. Chapters 1 and 2 have been signifi cantly changed from the eighth edition to provide a better perspective on sustainability, environmental science as a whole, chemical fate and transport, cycles of matter, the nature of environmental chemistry, and green chemistry. The chapter on terrorism in the eighth edition has been removed, but specifi c aspects of this topic, such as the potential role of toxic substances in terrorist attacks, have been placed in other chapters. Because of the importance of energy to the environment and sustainability, an extensive new chapter on this topic has been added to the book. Separate chapters on basic chemistry and organic chemistry that were in the seventh and earlier editions have not been included, but may be obtained from the author or publisher in pdf format upon request.

The book views the environment as consisting of fi ve spheres: (1) hydrosphere, (2) atmosphere, (3) geosphere, (4) biosphere, and (5) anthrosphere. It emphasizes the importance of the anthrosphere—

that part of the environment made and operated by humans and their technologies. This environmental sphere has so much infl uence on the Earth and its environmental systems that, according to Nobel Prize winner Paul Crutzen, the Earth is leaving the Holocene epoch, throughout which humankind has existed on Earth until now and is entering the Anthropocene epoch, in which human infl uences, such as emissions of gases that signifi cantly affect the warming and protective functions of the atmosphere, will have a dominant infl uence on conditions under which humankind exists on Earth. Since technology will in fact be used to attempt to support humankind on the planet, it is important that the anthrosphere be designed and operated in a manner that is compatible with sustainability and interacts constructively with the other environmental spheres. In this endeavor, environmental chemistry has a key role to play.

Environmental chemistry has evolved signifi cantly since the fi rst edition of Environmental Chemistry was published in 1972. (One interesting footnote to this evolution has been that with each new edition the calculation of the pH of ordinary rainwater has had to be revised because levels of atmospheric carbon dioxide had increased enough since each preceding edition to affect the result.) Whereas in the early 1970s environmental chemistry dealt largely with pollution and its effects, it now has a current emphasis upon sustainability. During the lifetime of the book, problems with organochlorine pesticides and detergent phosphates that cause water eutrophication have largely disappeared as the manufacture and sale of these substances have essentially ceased. When the book was fi rst published, it was not known with certainty what happened to large quantities of carbon monoxide emitted to the atmosphere by automobiles; it was suspected that soil microorganisms metabolized this pollutant, but it is now known that the ubiquitous hydroxyl radical scavenges CO from the atmosphere. In 1972, the potential for stratospheric ozone depletion was just emerging as a major issue, but it was not known that refrigerant chlorofl uorocarbons (freon compounds) were predominantly responsible for this threat. As the book progressed through various editions, the threat of these materials was revealed; the southern hemisphere springtime Antarctic ozone hole

(29)

xxviii Preface was discovered, which grew ominously year by year; the manufacture of chlorofl uorocarbons was banned as a consequence; and Molina, Rowland, and Crutzen shared a well-deserved Nobel Prize, the fi rst ever in environmental chemistry, for their work in this fi eld. The potential for greenhouse warming due to growing emissions of infrared-capturing carbon dioxide, methane, and other gases was shown to be a potentially huge problem for Earth and one that has not yet been resolved. In 1972, the terms green chemistry and industrial ecology had not yet been coined, but these disci- plines emerged from the 1990s as crucial elements of environmental chemistry.

Chapter 1 provides an overview and background in environmental and sustainability science.

The chapter is introduced with a brief discussion of the central issue of our time—energy, “From the Sun to Fossil Fuels and Back Again.” This chapter introduces chemical fate and transport, environmental terrorism, and environmental forensics.

Chapter 2 defi nes environmental chemistry and green chemistry in some detail. The chapter discusses the important concept of cycles of matter. It introduces the anthrosphere, how it integrates with the other environmental spheres, and its effects on Earth. Components of the anthrosphere that infl uence the environment are discussed with emphasis on the all-important infrastructure that is part of the anthrosphere.

Chapters 3 through 8 deal with the hydrosphere. Chapter 3 introduces the special characteristics of water and the environmental chemistry of water. The remaining Chapters 4 through 8 discuss specifi c aspects of aquatic chemistry, aquatic biochemistry, and water sustainability and treatment.

Chapters 9 through 14 discuss atmospheric chemistry. Chapter 14 emphasizes the greatest suc- cess story of environmental chemistry to date—the study of ozone-depleting chlorofl uorocarbons, which resulted in the fi rst Nobel Prize being awarded in environmental chemistry as mentioned above. It also emphasizes the greenhouse effect, which may be the greatest of all threats to the global environment as we know it.

Chapters 15 and 16 deal with the geosphere, the latter chapter emphasizing soil and agricultural chemistry. Included in the discussion of agricultural chemistry is the important and controversial new area of transgenic crops. Another area discussed is conservation tillage, which makes limited use of herbicides to grow crops with minimum soil disturbance.

Chapter 17 goes into detail on the topic of green chemistry and the closely related area of industrial ecology. Chapter 18 discusses resources and sustainable materials.

Chapter 19, on energy, is new as a separate chapter in the ninth edition. Entitled “Sustainable Energy: The Key to Everything,” it covers key topics on sustainable energy including conservation and renewable sources. The chapter ends with a proposed system of industrial ecology designed to produce methane from renewable biofuels and hydrogen generated from the electrolysis of water using renewable wind or solar energy.

The nature and environmental chemistry of hazardous wastes are covered in Chapter 20 and industrial ecology for waste minimization, utilization, and treatment in Chapter 21.

Chapters 22 and 23 cover the biosphere. Chapter 22 is an overview of biochemistry with emphasis on environmental aspects. Chapter 23 introduces and outlines the topic of toxicological chemistry.

Chapter 24 discusses the toxicological chemistry of various classes of chemical substances.

Chapters 25 through 28 deal with environmental chemical analysis, including water, wastes, air, and xenobiotics in biological materials.

As noted above, two chapters on basic chemistry and organic chemistry that were present in the seventh and earlier editions have been removed from this edition for the sake of brevity. Readers who need this material can obtain fi les containing these chapters from the publisher or the author.

I welcome comments and questions from readers. I can be reached by e-mail at manahans@

missouri.edu.

Stanley E. Manahan

(30)

xxix

Author

Stanley E. Manahan is professor emeritus of chemistry at the University of Missouri–Columbia, where he has been on the faculty since 1965. He received his AB in chemistry from Emporia State University in 1960 and his PhD in analytical chemistry from the University of Kansas in 1965.

Since 1968 his primary research and professional activities have been in environmental chemis- try, toxicological chemistry, and waste treatment. His classic textbook, Environmental Chemistry, has been in print continuously in various editions since 1972 and is the longest standing title on this subject in the world. His other books are Fundamentals of Environmental Chemistry, 3rd ed. (Taylor

& Francis/CRC Press, 2009), Fundamentals of Sustainable Chemical Science (Taylor & Francis/

CRC Press, 2009), Environmental Science and Technology, 2nd ed. (Taylor & Francis, 2006), Green Chemistry and the Ten Commandments of Sustainability, 2nd ed. (ChemChar Research, Inc, 2006), Toxicological Chemistry and Biochemistry, 3rd ed. (CRC Press/Lewis Publishers, 2001), Industrial Ecology: Environmental Chemistry and Hazardous Waste (CRC Press/Lewis Publishers, 1999), Environmental Science and Technology (CRC Press/ Lewis Publishers, 1997), Hazardous Waste Chemistry, Toxicology and Treatment (Lewis Publishers, 1992), Quantitative Chemical Analysis (Brooks/Cole, 1986), and General Applied Chemistry, 2nd ed. (Willard Grant Press, 1982).

Dr. Manahan has lectured on the topics of environmental chemistry, toxicological chemistry, waste treatment, and green chemistry throughout the United States as an American Chemical Society Local Section Tour Speaker and has presented plenary lectures on these topics in international meetings in Puerto Rico; the University of the Andes in Mérida, Venezuela; Hokkaido University in Japan; the National Autonomous University in Mexico City; France; and Italy. He was the recipient of the Year 2000 Award of the Environmental Chemistry Division of the Italian Chemical Society. His research specialty is gasifi cation of hazardous wastes.

(31)

(32)

1

1 The Environment and Sustainability Science

1.1 FROM THE SUN TO FOSSIL FUELS AND BACK AGAIN

An old Chinese proverb states that, “If we do not change direction, we are likely to end up where we are headed.” The New Millennium has brought with it evidence that we have been on a course that, if not altered, will have profound, unpleasant effects on humankind and on the Earth upon which this species and all other living things depend for their existence. The World Trade Center attacks of September 11, 2001, as well as later attacks on the London subway system, trains in Madrid, hotels in Mumbai, and other places around the world showed the vulnerability of our civilization to malevolent actions of those who feel compelled to commit evil acts and raised concerns about the possibilities for even more damaging attacks with chemical, biological, or radioactive agents. The fi rst part of 2008 saw runaway prices for key commodities including petroleum, metals such as copper, and grain. Crude oil prices reached almost $150 per barrel in July 2008 and predictions were made that gasoline prices in the United States would exceed $5.00 per gallon for the foreseeable future. These trends were reversed in the latter part of 2008 with the occurrence of the greatest economic collapse the world had seen since the Great Depression of the 1930s. Housing prices, which had reached levels unsupportable by people with ordinary incomes, collapsed, and the prices of some commodities plummeted. In early 2009, world leaders were struggling to fi nd solutions to severe economic problems.

As humans and their governments struggle with economic challenges, evidence has continued to gather that their activities are degrading the Earth’s life support system upon which they depend for their existence. The emission to the atmosphere of carbon dioxide and other greenhouse gases is almost certainly causing global warming. During the early 2000s, the Arctic ice cap diminished to a level never before observed in recorded history. Discharge of pollutants has degraded the atmosphere, hydrosphere, and geosphere in industrialized areas. Natural resources including minerals, fossil fuels, freshwater, and biomass have become stressed and depleted. The productivity of agricultural land has been diminished by water and soil erosion, deforestation, desertifi cation, contamination, and conver- sion to nonagricultural uses. Wildlife habitats including woodlands, grasslands, estuaries, and wetlands have been destroyed or damaged. About 3 billion people (half of the world’s population) live in dire poverty on less than the equivalent of U.S. $2 per day. The majority of these people lack access to sani- tary sewers and the conditions under which they live give rise to debilitating viral, bacterial, and pro- tozoal diseases including malaria and diarrhea. At the other end of the standard of living scale, a relatively small fraction of the world’s population consumes an inordinate amount of resources with lifestyles that involve living too far from where they work, in energy-wasting houses that are far larger than they need, commuting long distances in large “sport utility vehicles” that consume far too much fuel, and overeating to the point of unhealthy obesity with accompanying problems of heart disease, diabetes, and other obesity-related maladies.

In a sense, the history of humankind and its relationship to Planet Earth is a story of “from the sun to fossil fuels and back again.” During virtually all their existence on Earth, humans have been dependent upon the bounty provided by the sun. Solar radiation provided the warmth required for humans to exist and was augmented by fi re from burning of biomass generated by photosynthesis