Identifying Deficiencies in the Environmental ... - ACS Publications

international educational literature and general chemistry textbooks, that in spite of the importance of plastics and elas- tomers in the modern world...
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Research: Science and Education

Identifying Deficiencies in the Environmental Chemistry Educational Literature Thi Hoa Tran and Stephen W. Bigger School of Life Sciences & Technology, Victoria University, Melbourne City MC, Victoria 8001, Australia Tony Kruger School of Education, Victoria University, Melbourne City MC, Victoria 8001, Australia John D. Orbell* School of Life Sciences & Technology, Victoria University, PO Box 14428, Melbourne City MC, Victoria 8001, Australia; [email protected] Saman Buddhadasa and Sebastian Barone Australian Government Analytical Laboratories, South Melbourne, Victoria 3205, Australia

Background It is often assumed that the curriculum of a discipline such as chemistry puts an appropriate emphasis on areas that relate to real-world activities. However, it is evident that for some areas this is certainly not the case. For example, we have recently demonstrated, through a comprehensive survey of the international educational literature and general chemistry textbooks, that in spite of the importance of plastics and elastomers in the modern world, the area of polymer chemistry has been seriously neglected (1, 2). In response to this we recently embarked on a program to design and publish appropriate educational experiments in polymer chemistry (2, 3). In the area of environmental chemistry, it would not be surprising if similar deficiencies exist. For example, it may be argued that the three environmental domains, air, water, and soil, are of comparable importance in the real world and should therefore be equally represented in the environmental chemistry educational literature and curriculum. Using a methodology analogous to that used to reveal an under-representation of polymer science, we conducted a survey of environmental chemistry laboratory experiments reported in the Journal of Chemical Education and Education in Chemistry from 1969 to 2000. The experiments were categorized as being related to air, water, or soil. During the same period, a similar survey was carried out for commonly used environmental chemistry textbooks, assessing the relative number of pages devoted to these environmental domains. The environmental chemistry laboratory experiments were also analyzed with respect to the extent to which each experiment integrates the four traditional areas of chemistry— organic, inorganic, physical, and analytical. The concept of the “integrated” chemistry experiment has been considered as a means of providing students with a more holistic view of chemistry and the way it is applied in the real world (4 ). Results and Discussion It has been suggested that students cannot gain an adequate appreciation of environmental chemistry without doing laboratory-based work (5). For this reason, environmental chemistry laboratory programs are considered to be a vital component of environmental chemistry courses (6 ). There is anecdotal evidence to suggest that many laboratory

courses in environmental chemistry are self-designed or drawn from standard methods. Indeed, this is true of our own courses, although such standard methods invariably require significant modification to adapt them to the undergraduate laboratory. Although the mainstream chemical education journals (Journal of Chemical Education and Education in Chemistry) are increasingly incorporating environmental chemistry experiments, the practice of in-house development based on standard methods raises concern that significant educational material is not finding its way into the educational literature. It is acknowledged that such material could perhaps be found on the Internet via home pages for environmental chemistry courses and syllabi. However, to implement laboratory experiments, considerable detail is usually required and to obtain such information from the Internet is likely to be an onerous task. Furthermore, this approach might not be feasible in many developing countries where resources are limited. We would like to encourage educators to share environmental chemistry courses they have developed from standard methods by publishing them in the educational literature. Figure 1 shows the cumulative total of environmental chemistry experiments (relating to air, water, and soil combined), and the cumulative totals relating to these domains separately, reported in these journals from 1969 to 2000.1 In categorizing these experiments, only those that describe laboratory-based experiments were considered. Purely descriptive articles or those relating to course or subject description were excluded. It is apparent from Figure 1 that both air and soil (in particular) are seriously under-represented. There are several possible explanations for this, including the relative ease of constructing and implementing water-based experiments compared to those that are air-based or soil-based; or the trend could reflect a perception that air and soil chemistry are more complex and challenging than water chemistry. This is a well-founded perception of soil chemistry, which has a stronger cross-disciplinary element. Owing to its added complexity, soil chemistry is often only peripherally addressed in environmental chemistry courses (especially in the first year). However, we would argue that it does not need to be. In our view, soil is a powerful vehicle for introducing students to a range of important chemical concepts such as ion exchange, surface chemistry, structural inorganic chemistry, to name but a few.

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Figure 1. The cumulative total of environmental chemistry experiments (relating to air, water, and soil combined) and the cumulative totals relating to these domains separately reported in the Journal of Chemical Education and Education in Chemistry from 1969 to 2000.

Figure 2. The cumulative percentage of pages relating to air, water, and soil in commonly available environmental chemistry textbooks from 1972 to 2000.

A particularly interesting feature of the data in Figure 1 is a reflection of the sharp upsurge of interest in environmental issues in the early 1970s and again in the late 1980s and early 1990s (7). Therefore, it is possible that such surveys also reflect changes in attitudes towards important issues. Figure 2 compares the cumulative percentage of pages relating to air, water, and soil in commonly used environmental chemistry textbooks (listed in the box on page 1695) from 1972 to 2000. These data also reveal soil to be consistently under-represented, although water and air can now be considered comparable. The reason for the under-representation of soil is, again, probably related to the perceived (and real) complexity of this medium. Figure 3 provides a comparison of the overall representation of the three environmental domains with respect to the educational literature and environmental chemistry textbooks. Soil can be seen to be seriously under-represented in both of these resources. The 92 environmental chemistry experiments surveyed

in the educational literature were also categorized according to the extent to which they integrate two or more of the four traditional areas of chemistry—analytical (A), inorganic (I), organic (O), and physical (P). There is necessarily an element of subjectivity in this exercise. An experiment was scored as including a particular area if it was considered to teach techniques or principles traditionally associated with that area. This criterion is based on the one used by investigators of the “integrated chemistry approach”: “an integrated chemistry laboratory refers to the use of experiments that teach techniques or principles obtained from two or more areas of chemistry (e.g. analytical and physical chemistry)” (4). Experiments that are considered to demonstrate solely analytical principles or techniques are denoted “A”, those that are considered to demonstrate both analytical and physical principles or techniques are denoted “AP”, and so on. The outcome of this analysis is represented in Figure 4. To clarify this approach, three representative experiments are discussed in terms of their categories.

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Category Figure 4. Degree of integration of the four traditional areas of chemistry in the environmental chemistry laboratory experiments surveyed.

Journal of Chemical Education • Vol. 78 No. 12 December 2001 • JChemEd.chem.wisc.edu

Research: Science and Education

1. Gas Chromatographic Determination of Environmentally Significant Pesticides. Ruzinki, W. E.; Beu, S. J. Chem. Educ. 1982, 59, 614–615. This experiment introduces students to gas chromatography as an analytical technique. There is an emphasis on sample preparation and instrumental parameters. Therefore, this experiment was categorized as “A”. 2. Laboratory Experiments on Electrochemical Remediation of the Environment. Part 4. Color Removal of Simulated Wastewater by Electrocoagulation–Electroflotation. Ibanez, J. G.; Singh, M. M.; Szafran, Z. J. Chem. Educ. 1998, 75, 1040–1041. This experiment is basically electrochemical (physical) and employs electrolysis to generate a metal hydroxide sludge capable of removing pollutants from wastewater. Students are also introduced to the concepts of coagulation and flotation (physical). Therefore this experiment was categorized as “P”. 3. Phosphate Fertilizers in Soils. Morrison, R. J.; Dandy, A. J. Educ. Chem. 1979, 16, 176–177. This experiment introduces students to principles of both surface chemistry and colorimetry. More specifically, it describes the determination of adsorption isotherms (physical) with respect to the uptake of phosphate by soil. The procedure also requires the determination of phosphate concentrations using a colorimetric method (analytical). Therefore, this experiment was categorized as “AP”. It is evident from Figure 4 that none of the surveyed experiments are considered to integrate more than two of the traditional areas of chemistry. It is also noticeable that analytical chemistry alone is by far the most represented. This is not surprising, given the role of environmental measurement and analysis in environmental chemistry. Out of all possible combinations of one or two areas, we found no experiments that could be categorized as O, I, OI, or OP. Other higher combinations include AIO, AIP, AOP, IOP, and AIOP. Although one could argue that the bias toward an area such as analytical chemistry is unavoidable, such an analysis provides a basis for optimizing the level of integration in the design of environmental chemistry laboratory experiments. Conclusions We conclude from this study that there is a need for the development of more environmental chemistry educational material, in the form of published laboratory experiments and textbook material, that is related to soil chemistry and soil contamination. There is also a lesser, but significant, requirement for the development and publication of laboratory experiments relating to air chemistry and air pollution. We are currently developing such material. Acknowledgment We would like to acknowledge the support of the Australian Government Analytical Laboratories (AGAL) for the provision of a five-month work experience program for Thi Hoa Tran. Note 1. A listing of all experiments included in the survey is available upon request.

Literature Cited 1. Bigger, S. W.; Hodgson, S. C.; Orbell, J. D.; Scheirs, J. Polym. Prepr. 1999, 40, 598–599.

Environmental Chemistry Textbooks Surveyed (1972–2000) Year

Textbook

1972

Stephen, H. S.; Seager, S. L. Environmental Chemistry: Air and Water Pollution; Scott, Foresman: Glenview, IL.

1973

Manahan, S. E. Environmental Chemistry; Willard Grant: Boston.

1975

Manahan, S. E. Environmental Chemistry, 2nd ed.; Willard Grant: Boston.

1976

Stephen, H. S.; Seager, S. L. Environmental Chemistry: Air and Water Pollution, 2nd ed.; Scott, Foresman: Glenview, IL. Moore, J. W.; Moore, E. A. Environmental Chemistry; Academic: New York.

1977

Environmental Chemistry; Bockris, J. O’M., Ed.; Plenum: New York.

1978

Bailey, R. A. Chemistry of the Environment; Academic: New York.

1979

Manahan, S. E. Environmental Chemistry, 3rd ed.; Willard Grant: Boston.

1980

Environmental Chemistry, the Earth–Air–Water Factory; Raiswell, R. W.; Brimblecombe, P.; Dent, D. L.; Liss, P. S., Eds.; Edward Arnold: London.

1984

Manahan, S. E. Environmental Chemistry, 4th ed.; Willard Grant: Boston.

1985

O’Neill, P. Environmental Chemistry; Allen & Unwin: Boston.

1986

Understanding Our Environment; Hester, R. E., Ed.; Royal Society of Chemistry: Bristol, UK.

1991

Bunce, N. J. Environmental Chemistry; Wuerz: Winnipeg, MB. Manahan, S. E. Environmental Chemistry, 5th ed.; Willard Grant: Boston.

1992

Understanding Our Environment: An Introduction to Chemistry and Pollution, 2nd ed.; Harrison, R. M., Ed.; Royal Society of Chemistry: Cambridge, UK.

1993

Manahan, S. E. Fundamentals of Environmental Chemistry; Lewis: Boca Raton, FL. Bunce, N. J. Introduction to Environmental Chemistry, 2nd ed.; Wuerz: Winnipeg, MB. O’Neill, P. Environmental Chemistry, 2nd ed.; Chapman & Hall: New York. Chemistry and Biology of Water, Air, and Soil: Environmental Aspects; Tölgyessy, J., Ed.; Elsevier: Amsterdam.

1994

Bunce, N. J. Environmental Chemistry, 2nd ed.; Wuerz: Winnipeg, MB. Manahan, S. E. Environmental Chemistry, 6th ed.; Lewis: Boca Raton, FL.

1995

Baird, C. Environmental Chemistry, Freeman: New York.

1996

An Introduction to Environmental Chemistry; Andrews, J. E.; Brimblecombe, P.; Jickells, T. D.; Liss, P. S., Eds.; Blackwell Science: Cambridge, MA. Spiro, T. G.; Stigliani, W. M. Chemistry of the Environment; Prentice Hall: New York.

1997

Connell, D. W. Basic Concepts of Environmental Chemistry; Lewis: Boca Raton, FL.

1999

Baird, C. Environmental Chemistry, 2nd ed.; Freeman: New York. Understanding Our Environment: An Introduction to Chemistry and Pollution, 3rd ed.; Harrison, R. M., Ed.; Royal Society of Chemistry: Cambridge, UK. Loon, G. W. V.; Duffy, S. J. Environmental Chemistry: A Global Perspective; Oxford University Press: New York. Manahan, S. E. Environmental Chemistry, 7th ed.; Lewis: Boca Raton, FL.

2. Hodgson, S. C.; Orbell, J. D.; Scheirs, J.; Bigger, S. W. J. Chem. Educ. 2000, 77, 745–747. 3. Hodgson, S. C.; Casey, R. J.; Orbell, J. D.; Bigger, S. W. J. Chem. Educ. 2000, 77, 1631–1633. 4. Miller, K. M.; Hage, D. S. J. J. Chem. Educ. 1995, 72, 248–250. 5. Davison, W.; Hewitt, C. N. Educ. Chem. 1993, 30, 48–50. 6. Willey, J. D.; Avery, G. B.; Manock, J. J.; Skrabal, S. A.; Stehman, C. F. J. Chem. Educ. 1999, 76, 1693–1694. 7. De Steiguer, J. E. The Age of Environmentalism; McGraw-Hill: New York, 1997.

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