in this issue Chemistry and the Environment Environmental issues are prevalent in the news these davs-from warnmgs of impending glo6al catastrophes to local concerns about pollution in previously pure waterways. While many aspects of the discussions deal more with economics and politics than science, the citizen chemist is often annalled bv the wav the scientific facts and theories are'kisstatei and h o i t h e roles of science and technology in both causing and curing these problems are misunderstood. One of the most valuable contributions teachers of nonscience (and even science) majors can make may well be to prepare their students to deal rationally with these issues as voters and citizens in our participatory democracy. Chemists can help with understanding environmental issuesby providing the data and theories that define the problem, assess its seriousness, and explain its causes. Chemists can then use this information to produce new processes and materials to help solve the pr&lems. This issue contains a variety of articles that cover one or both of these interactions between Chemistry and the Environment. Each oflers the teacher interesting backmound material or teaching ideas that can be usedio introduce environmental chemistry into the classroom or to make meaningful contributions to their communities. Certain chemical species are notorious for their toxic reactions when they enter the environment in unnatural forms or concentrations. Two such major pollutants, heavy metals and petroleum hydrocarhuns, h e discus~edin art,cles by EPA scientists, who review what is known about thcir chcmistw. Kn'shnamurthv roaee .. 3471discusses the complex relati"onships between organisms and the heavy metals. These metals are transported throueh .. the environmcnt and accumulated in organisms primarily through the orocess of biomcthvlation. Thev have been resoonsible for such ecological di"sasters areVthemercury poisoning of Minimata Bay and yet are necessary as catalysts in many higher organisms. The role that microorganisms play in transporting these metals in the environment is reviewed and areas f& further research are delineated. Another familiar class of pollutants migrating through the environment is made up of the petroleum products, particularly gasoline, which leak from underground storage systems. Here, the migration through the ground and into water sources is governed greatly by the type of soil and by the various physical means of dispersal. Chen (page 357) defines the basic soil types and their properties. He then outlines the many ways that transport can occur within the subsoil. He ends with a summary of what is known precisely about these methods and what we still need to know to manage these spills properly. One of the more sur~risineenvironmental alarms in recent years has resultei fromuthe discovery that radioactive radon-222 was present in many homes. The irony of this problem is that the danger is from a natually occuring substance and that its oresence in sienificant auantities resulted from the welcintentioned e?forts to respond to anw crisis. This other environmental problem-the e n e r-. byproduct of'radioacti\;e decay in the soil is seeping into homes that had been insulated so efficiently that a serious
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346
Journal of Chemical Education
level of the eas could build uo. ~articularlvin basements. Atwood lp&e 331, reviews &>current k;lowledge about the infiltration of radon into homes. discussine the chemistry of its production, showing how far we have come in asssessing what the hazards are, and giving statistical comparisons to other risk factors. He then outlines procedures for detecting and reducing radon levels in our own homes. This information provides teachers with the material to explain this hen omen on to their students or to assist those in their c&nmunity to take appropriate action. The common thread running through all of these articles and many others that we read on environmental concerns is the interdependency of organisms and their biochemical processes. Riohemical reactions are never isolated in nature; what benefits one organism can destroy another. Unbalancing the ecosytem can be disaterous even for the organism that initially benefits from this imbalance. To help teachers show this interdependency, Ochiai (page 356) summarizes the major chemical systems in the biosphere in a simple, one-diagram outline. Laboratory experiments incorporating environmental topics have a special synergy. The laboratory becomes more interesting because of its real-world immediacy and the orinci~lesinvolved in the environmental process are made more meaningful with hands-on experience. The Modern Student Laboratory this month features three experiments with environmental themes. Koubek and Stewart (page A1461 use ion chromatography in their experiment'that analyzes the sulfur in coal. Since this sulfur is directlv related to SO9 emissions and the acid rain phenomenon it can be springboard for further discussion. It is not always easy to find environmentally significant experiments that can be done a t the introductory course level. Amey (page A1481 has devised a simple method for analyzing smog that utilizes a inexpensive toy balloon for the gas cell on an FTIR spectrophotometer. He points out t h a t this instrument is simple and robust enough to weathcr b e ~ m i n g students, and thcy can understand the undcrlring fundamentals of infrared spectroscopy .. early in the co&ey While the above two experiments have dealt with analyzing environmental problems, the third one deals with chemistry that can solve one. The crisis in landfill space in desirlarge urhan areas ha* made hiodegrndal)le able. Further, the dwindling of natural nonrenewable resources, such as petroleum products, has scientists looking for renewable resources for startingmaterials. Riopolymer starches fill tmth thehe reuuirements: thev he used to omduce films that biodegrade, and the basi"c corn or potato starch is an easilv oroduced commoditv. Somefield and Blume (page ~l"i5i)present several short experiments that illustrate interestine chemistrv and can be the beeinning of interdisciplinary'discussio& of related biological, toxicoloeical. ecoloeical. and economical ~roblems. concern about tlhe diminishing sup3y of fossil-based fuels has resulted in nationally supported efforts to introduce energy education programs in the schools. Kauffian and Zafran (paw 366) report on a kit of 10 modules usine commericall~available products to demonstrate energy generation, conversion, and utilization. These kits were prepared by NEED, an association of energy educators, with government support and provide teachers with readyto-go modules to supplement existing units or to serve as an independent unit on energy issues.
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