- Email: [email protected]
Arsenic in the environment part I: Cycling and characterization. Arsenic in the environment part II: Human health and Ecosystem Effects
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ChemicalEngineerin#Sci ..... Vol. 50, No. 4, pp. 741-742, 1995 Elsevier Science Ltd Printed in Great Britain.
0000000000000000000000000000000000000000000000000000000000O000000000000~0000O0
Arsenic in the Environment Part I: Cycling and Characterization. Arsenic in the Environment Part II: Human Health and Ecosystem Effects. Edited by J. O. N.RIAGU. Wiley, New York, 1994; Part I: 430 pp., Part II: 293 pp.
Numerical Methods for Problems with Moving Fronts. By BRUCE FINLAYSON. Ravenna Park Publishing, 1992, 605 pp. ISBN: 0963 17650 1 Bruce Finlayson, a veteran user of numerical methods, has a new book out, Numerical Methods for Problems with Moving Fronts. The book gives a clear introduction to finite element (or, as some prefer to call them, "Finite elephant") and finite difference methods, starting with one-dimensional problems on fixed grids and gradually building up to higher-dimensional problems and to a variety of techniques for using moving meshes. The second half of the book is a- large set of case studies. The book could, in fact, be called "Numerical Methods by Example". Finlayson discusses different solution methods applied to solve'the convective diffusion equation with adsorption or reaction, phase change problems, the Navier-Stokes equations, polymer flows, and flows through porous media. Much detail is provided--none of that annoying "the derivation is left as an exercise for the reader" - and there are copious figures throughout. The book is ambitious in its scope; many readers will, depending on their background, want to read or skim the introductory chapters and then turn directly to the example problems of most interest to them. If the book has a fault, it is the presence of so many examples with so little unifying theory. It would have been nice to see more discussion of when different methods are to be preferred---or even the names of some methods. For example, conformal mapping is not, as far as I could see, ever mentioned by name, and is not in the index, although the method is mentioned in passing. Also, no mention is made of competing methods such as boundary element or other Green's function-based methods, or of the different methods used in turbulence modeling to avoid the moving front problem. But then again, perhaps this was wisely left to be the subject of another book, as this one is already over 600 pages. The book comes with a supplementary software package for Macintosh computers. This is a great idea, but to my surprise, in spite of the interface being the standard Mac pull-down windows, it was not obvious how to use the software--until I flipped back to the appendix on the program and read that I need to do three trivial (but not clearly marked) steps: select an equation, select initial conditions, and compute. When I did play with the programs, I managed fairly quickly to get one of those helpful, explanatory messages, "Error 11 at 00894" that we all love. Nonetheless, the program seems reasonably robust and lets the user supplement the already extensive results included in the book. Overall recommendation: This is a clearly written reference which should be on the shelf of anyone studying moving front problems. To order, contact Ravenna Park Publishing, Inc., 6315 22nd Ave. NE Seattle, WA 98115-6919; phone (206) 5243375. LYLE. H. U N G A R
Department of Chemical EngineerinO University of Pennsylvania Philadelphia, PA, 19104, U.S.A
As the "physician's accomplice, undertaker's benefactor, and grave worm's provider" (Bierce, 1911) arsenic has had a long and often sordid past that is unequaled among the elements. Mention helium and one thinks of balloons; for neon--signs, tin--cups, copper--kettles. With arsenic we think of POISON. Arsenic served as the poison of choice for more than 2 millennia having been used as a poudre de succession by nefarious men and women who became emperors (Nero), popes (Alexander VI), merchants (Toffana), and wealthy widows of stature. Poisoning with wine to which was added "one teaspoonful of arsenic, then a half teaspoonful of strychnine and then just a pinch of cyanide", became comic theater with the 1941 Broadway hit "Arsenic and Old Lace", in which the elderly Brewster sisters charitably bumped off lonely men and buried them in their cellar (Kesselring, 1947). Unfortunately arsenic poisoning is not limited to the ancients and the stage. Arsenic and its compounds are present day environmental contaminants as well as workplace hazards in the manufacture of treated lumber, pesticides, semi-conductors, metals and veterinary pharmaceuticals. Worldwide annual production of arsenic trioxide, the major commercial arsenic compound, has been relatively stable at about 50 million kg over the past 60 years. Waste from manufacturing industries, mining, and the burning of fossil fuels adds about 82 million kg/yr of arsenic to the soil. Arsenic is the 20th most prevalent element in the earth's crust, the 14th in sea water, and the 12th in the human body. That the chemical form and the dose of a substance "differentiate a poison and a remedy" is very well illustrated by arsenic compounds. Their use as medicaments and poisons and the ubiquitous presence of arsenic compounds in the environment as a natural constituent attest to their varied bioactivity. Arsine gas, ASH3, is regarded as the most toxic form of arsenic. Inorganic and organic arsenites (As III) are also quite toxic while the arsenates (As V) are less toxic. Metallic arsenic is relatively nontoxic. Hippocrates ( ~ 400 B.C.E.) administered two arsenic ores (realgar and orpiment) as remedies for ulcers and for cauterization of the skin. Potassium arsenite, or Fowler's solution, was used widely from 1809 to 1950 as a treatment for rheumatism, neuralgias, anorexia, and a variety of other ailments until this solution was recognized as being associated with skin cancer. Arsphenamine, developed by Paul Ehrlich and co-workers, was the main therapeutic agent for syphilis from 1909 to 1948 until it was replaced by penicillin. Organoarsenicals continue to be used in veterinary medicine as antifilarial drugs, cattle and sheep dips, and growth promoters. Studies dating as far back as the 1880s have provided evidence that arsenic exposure is associated with human dermal and lung cancers. Recent studies indicate that arsenicals are not direct mutagens but mutation modifying agents and that they are mainly tumor promoters as opposed to complete carcinogens. Arsenic appears to inhibit certain enzymes required for DNA repair or replication. Humans appear to be among the most sensitive of vertebrate animals to the effects of arsenic exposure and the only species for which arsenic is carcinogenic. A link with oncogenic viruses such as human papilloma virus and tumors in arsenicexposed workers has also been postulated. The U.S. EPA and the International Agency for Research on Cancer (IARC) list inorganic arsenic as a human carcinogen. Arsenic is found throughout the biosphere at low levels but may exist at much higher concentrations in the vicinity of anthropogenic sources, such as smelters, phosphate
741
742
Book Reviews
fertilizer plants, metal mines, and coal-fired power plants. For instance, copper smelting emits up to 1 g of arsenic waster for each kg of copper produced. A smelter in Tacoma, WA, discharged 64,000 kg arsenic/yr into Puget sound for decades and produced soil surface layer contamination around the site reaching 380ppm. Waste recovery and treatment of arsenic from aqueous systems and drinking water supplies constitutes a significant technological challenge. Currently, the maximum contaminant level (MCL) in the U.S. for arsenic is 0.05 ppm and an intended change to 0.002 ppm by 1996 has been announced. The concentration of arsenic in drinking water estimated to produce a 1 in 106 level of cancer risk is 0.0022/~g/I (0.0022 ppb) and it is estimated that there is a 9% incidence of symptoms of arsenic toxicity with exposure at the current MCL. Concentrations of arsenic in water supplies can be high, but wastewater may be many orders of magnitude higher. For instance, wastewater from fertilizer plants has been reported in excess of 10 ppm arsenic. In general, marine organisms exhibit higher arsenic burdens than terrestrial organisms and aquatic ecosystems have appropriately received considerable attention. Arsenic in the Environment: Parts I and II was published this year by Wiley as Volumes 26 and 27 in the series Advances in Environmental Science and Technology. It may be surprising to some that there should appear a new twovolume treatise on arsenic, given that the arsenicals have been known for such a long time and have been thoroughly investigated. However, the only other comprehensive book in print in English on environmental arsenic is a text edited by Bruce Fowler in 1983 (Biological and Environmental Effects of Arsenic, Elsevier, New York, 281 pp.) The other major text in this field was produced by the National Academy of Sciences, Committee on Medical and Biological Effects of Environmental Pollutants in 1977 (NAS, Washington, DC). Arsenic in the Environment can be considered the grandchild of the NAS book. It is a more comprehensive work that includes the science circa 1977 plus the considerable body of scientific discovery that has arisen in the past 17 years. Jerome O. Nriagu, editor for this work, has edited 12 volumes for Wiley over the past decade. For this book, Nriagu has assembled contributing authors representing 15 countries, some of which have substantial problems with arsenic (e.g. China, Taiwan, Mexico). Their diverse experiences with arsenic contamination and the extensive citation of published works in English and foreign language journals are strengths of the book. Part I focuses on the chemistry of arsenic in soil and water, arsenic cycling
through the environment, and strategies for its removal through adsorption and transformation. Part II is concerned with human health effects and ecosystem damage from arsenic exposure. This volume contains comprehensive and extremely useful tables listing background levels of arsenic in air, waters, soils, rain, snow, fossil fuels, sediments, various flora and fauna. The table listing exposure limits and maximum concentration criteria is noteworthy. Chapter 11 of Part II written by Ronald Eisler is especially informative as it provides a good summary of the sources, fate, concentrations and biological activities of arsenic compounds. Arsenic in the Environment is an extensive resource that is likely to be the definitive work on arsenic for years to come. Although this book is well written and edited, it contains some unnecessary duplication of material that arises because of different authors writing on related topics. This duplication is common but avoidable with careful editorial guidance and editing. Production as a two-part text is likely to be an annoyance to some readers. Paring of redundancies and condensation of two indexes to one would have allowed this to appear as a single volume of under 700 pages. A chapter on risk assessment for arsenicals in air, water, soil, and solid waste would have been a useful addition. Finally, use of standardized units throughout the book and inclusion of a list of symbols would have removed some ambiguities and improved the readability of the book. However, these shortcomings are relatively minor and do not detract substantially from the quality of this text. This two-part set is an important addition to the library of toxicologists or environmental engineers concerned with environmental contamination (air, water or soil), risk assessment, or the toxicity of metal compounds. While we are witnessing a decline in the anthropogenic input of arsenic into the environment, the challenges posed by this contaminant will be with us for many years to come. PETER S. THORNE Department of Preventive Medicine and Environmental Health University of Iowa Iowa City, IA 54225-5000, U.S.A. REFERENCES
Bierce, A., 1911, The Devil's Dictionary, p. 8. Dell Publishers, New York. Kesselring, J., 1947, Arsenic and old lace, in Best Plays of the Modern American Theater (second series) (Edited by J. Gassner), pp. 459-510. Crown Publishers, New York.
ChemicalEngineerin#Sci ..... Vol. 50, No. 4, pp. 741-742, 1995 Elsevier Science Ltd Printed in Great Britain.
0000000000000000000000000000000000000000000000000000000000O000000000000~0000O0
Arsenic in the Environment Part I: Cycling and Characterization. Arsenic in the Environment Part II: Human Health and Ecosystem Effects. Edited by J. O. N.RIAGU. Wiley, New York, 1994; Part I: 430 pp., Part II: 293 pp.
Numerical Methods for Problems with Moving Fronts. By BRUCE FINLAYSON. Ravenna Park Publishing, 1992, 605 pp. ISBN: 0963 17650 1 Bruce Finlayson, a veteran user of numerical methods, has a new book out, Numerical Methods for Problems with Moving Fronts. The book gives a clear introduction to finite element (or, as some prefer to call them, "Finite elephant") and finite difference methods, starting with one-dimensional problems on fixed grids and gradually building up to higher-dimensional problems and to a variety of techniques for using moving meshes. The second half of the book is a- large set of case studies. The book could, in fact, be called "Numerical Methods by Example". Finlayson discusses different solution methods applied to solve'the convective diffusion equation with adsorption or reaction, phase change problems, the Navier-Stokes equations, polymer flows, and flows through porous media. Much detail is provided--none of that annoying "the derivation is left as an exercise for the reader" - and there are copious figures throughout. The book is ambitious in its scope; many readers will, depending on their background, want to read or skim the introductory chapters and then turn directly to the example problems of most interest to them. If the book has a fault, it is the presence of so many examples with so little unifying theory. It would have been nice to see more discussion of when different methods are to be preferred---or even the names of some methods. For example, conformal mapping is not, as far as I could see, ever mentioned by name, and is not in the index, although the method is mentioned in passing. Also, no mention is made of competing methods such as boundary element or other Green's function-based methods, or of the different methods used in turbulence modeling to avoid the moving front problem. But then again, perhaps this was wisely left to be the subject of another book, as this one is already over 600 pages. The book comes with a supplementary software package for Macintosh computers. This is a great idea, but to my surprise, in spite of the interface being the standard Mac pull-down windows, it was not obvious how to use the software--until I flipped back to the appendix on the program and read that I need to do three trivial (but not clearly marked) steps: select an equation, select initial conditions, and compute. When I did play with the programs, I managed fairly quickly to get one of those helpful, explanatory messages, "Error 11 at 00894" that we all love. Nonetheless, the program seems reasonably robust and lets the user supplement the already extensive results included in the book. Overall recommendation: This is a clearly written reference which should be on the shelf of anyone studying moving front problems. To order, contact Ravenna Park Publishing, Inc., 6315 22nd Ave. NE Seattle, WA 98115-6919; phone (206) 5243375. LYLE. H. U N G A R
Department of Chemical EngineerinO University of Pennsylvania Philadelphia, PA, 19104, U.S.A
As the "physician's accomplice, undertaker's benefactor, and grave worm's provider" (Bierce, 1911) arsenic has had a long and often sordid past that is unequaled among the elements. Mention helium and one thinks of balloons; for neon--signs, tin--cups, copper--kettles. With arsenic we think of POISON. Arsenic served as the poison of choice for more than 2 millennia having been used as a poudre de succession by nefarious men and women who became emperors (Nero), popes (Alexander VI), merchants (Toffana), and wealthy widows of stature. Poisoning with wine to which was added "one teaspoonful of arsenic, then a half teaspoonful of strychnine and then just a pinch of cyanide", became comic theater with the 1941 Broadway hit "Arsenic and Old Lace", in which the elderly Brewster sisters charitably bumped off lonely men and buried them in their cellar (Kesselring, 1947). Unfortunately arsenic poisoning is not limited to the ancients and the stage. Arsenic and its compounds are present day environmental contaminants as well as workplace hazards in the manufacture of treated lumber, pesticides, semi-conductors, metals and veterinary pharmaceuticals. Worldwide annual production of arsenic trioxide, the major commercial arsenic compound, has been relatively stable at about 50 million kg over the past 60 years. Waste from manufacturing industries, mining, and the burning of fossil fuels adds about 82 million kg/yr of arsenic to the soil. Arsenic is the 20th most prevalent element in the earth's crust, the 14th in sea water, and the 12th in the human body. That the chemical form and the dose of a substance "differentiate a poison and a remedy" is very well illustrated by arsenic compounds. Their use as medicaments and poisons and the ubiquitous presence of arsenic compounds in the environment as a natural constituent attest to their varied bioactivity. Arsine gas, ASH3, is regarded as the most toxic form of arsenic. Inorganic and organic arsenites (As III) are also quite toxic while the arsenates (As V) are less toxic. Metallic arsenic is relatively nontoxic. Hippocrates ( ~ 400 B.C.E.) administered two arsenic ores (realgar and orpiment) as remedies for ulcers and for cauterization of the skin. Potassium arsenite, or Fowler's solution, was used widely from 1809 to 1950 as a treatment for rheumatism, neuralgias, anorexia, and a variety of other ailments until this solution was recognized as being associated with skin cancer. Arsphenamine, developed by Paul Ehrlich and co-workers, was the main therapeutic agent for syphilis from 1909 to 1948 until it was replaced by penicillin. Organoarsenicals continue to be used in veterinary medicine as antifilarial drugs, cattle and sheep dips, and growth promoters. Studies dating as far back as the 1880s have provided evidence that arsenic exposure is associated with human dermal and lung cancers. Recent studies indicate that arsenicals are not direct mutagens but mutation modifying agents and that they are mainly tumor promoters as opposed to complete carcinogens. Arsenic appears to inhibit certain enzymes required for DNA repair or replication. Humans appear to be among the most sensitive of vertebrate animals to the effects of arsenic exposure and the only species for which arsenic is carcinogenic. A link with oncogenic viruses such as human papilloma virus and tumors in arsenicexposed workers has also been postulated. The U.S. EPA and the International Agency for Research on Cancer (IARC) list inorganic arsenic as a human carcinogen. Arsenic is found throughout the biosphere at low levels but may exist at much higher concentrations in the vicinity of anthropogenic sources, such as smelters, phosphate
741
742
Book Reviews
fertilizer plants, metal mines, and coal-fired power plants. For instance, copper smelting emits up to 1 g of arsenic waster for each kg of copper produced. A smelter in Tacoma, WA, discharged 64,000 kg arsenic/yr into Puget sound for decades and produced soil surface layer contamination around the site reaching 380ppm. Waste recovery and treatment of arsenic from aqueous systems and drinking water supplies constitutes a significant technological challenge. Currently, the maximum contaminant level (MCL) in the U.S. for arsenic is 0.05 ppm and an intended change to 0.002 ppm by 1996 has been announced. The concentration of arsenic in drinking water estimated to produce a 1 in 106 level of cancer risk is 0.0022/~g/I (0.0022 ppb) and it is estimated that there is a 9% incidence of symptoms of arsenic toxicity with exposure at the current MCL. Concentrations of arsenic in water supplies can be high, but wastewater may be many orders of magnitude higher. For instance, wastewater from fertilizer plants has been reported in excess of 10 ppm arsenic. In general, marine organisms exhibit higher arsenic burdens than terrestrial organisms and aquatic ecosystems have appropriately received considerable attention. Arsenic in the Environment: Parts I and II was published this year by Wiley as Volumes 26 and 27 in the series Advances in Environmental Science and Technology. It may be surprising to some that there should appear a new twovolume treatise on arsenic, given that the arsenicals have been known for such a long time and have been thoroughly investigated. However, the only other comprehensive book in print in English on environmental arsenic is a text edited by Bruce Fowler in 1983 (Biological and Environmental Effects of Arsenic, Elsevier, New York, 281 pp.) The other major text in this field was produced by the National Academy of Sciences, Committee on Medical and Biological Effects of Environmental Pollutants in 1977 (NAS, Washington, DC). Arsenic in the Environment can be considered the grandchild of the NAS book. It is a more comprehensive work that includes the science circa 1977 plus the considerable body of scientific discovery that has arisen in the past 17 years. Jerome O. Nriagu, editor for this work, has edited 12 volumes for Wiley over the past decade. For this book, Nriagu has assembled contributing authors representing 15 countries, some of which have substantial problems with arsenic (e.g. China, Taiwan, Mexico). Their diverse experiences with arsenic contamination and the extensive citation of published works in English and foreign language journals are strengths of the book. Part I focuses on the chemistry of arsenic in soil and water, arsenic cycling
through the environment, and strategies for its removal through adsorption and transformation. Part II is concerned with human health effects and ecosystem damage from arsenic exposure. This volume contains comprehensive and extremely useful tables listing background levels of arsenic in air, waters, soils, rain, snow, fossil fuels, sediments, various flora and fauna. The table listing exposure limits and maximum concentration criteria is noteworthy. Chapter 11 of Part II written by Ronald Eisler is especially informative as it provides a good summary of the sources, fate, concentrations and biological activities of arsenic compounds. Arsenic in the Environment is an extensive resource that is likely to be the definitive work on arsenic for years to come. Although this book is well written and edited, it contains some unnecessary duplication of material that arises because of different authors writing on related topics. This duplication is common but avoidable with careful editorial guidance and editing. Production as a two-part text is likely to be an annoyance to some readers. Paring of redundancies and condensation of two indexes to one would have allowed this to appear as a single volume of under 700 pages. A chapter on risk assessment for arsenicals in air, water, soil, and solid waste would have been a useful addition. Finally, use of standardized units throughout the book and inclusion of a list of symbols would have removed some ambiguities and improved the readability of the book. However, these shortcomings are relatively minor and do not detract substantially from the quality of this text. This two-part set is an important addition to the library of toxicologists or environmental engineers concerned with environmental contamination (air, water or soil), risk assessment, or the toxicity of metal compounds. While we are witnessing a decline in the anthropogenic input of arsenic into the environment, the challenges posed by this contaminant will be with us for many years to come. PETER S. THORNE Department of Preventive Medicine and Environmental Health University of Iowa Iowa City, IA 54225-5000, U.S.A. REFERENCES
Bierce, A., 1911, The Devil's Dictionary, p. 8. Dell Publishers, New York. Kesselring, J., 1947, Arsenic and old lace, in Best Plays of the Modern American Theater (second series) (Edited by J. Gassner), pp. 459-510. Crown Publishers, New York.