Community-based Projects in Analytical Chemistry Courses

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Community-Based Projects in Analytical Chemistry Courses Thomas J. Wenzel, Bates College

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ncluding a project that involves the analysis of a “real-world” sample is becoming more prevalent in undergraduate analytical chemistry courses. These projects are often capstone experiences in which students, equipped with a toolbox of analytical methods from prior experiments and coursework, are expected to solve problems similar to those faced by analytical chemists. The value of these projects as learning experiences has been discussed (1, 2); however, identifying projects that generate challenging problems and capture the student’s interest can seem difficult. Some instructors are having success by developing community-based projects.

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Chemical analysis projects Alanah Fitch at Loyola University– Chicago instructs students to work with community groups to measure the lead concentration in samples from nearby neighborhoods (3). Lead has been an excellent analyte because it represents a serious health threat and occurs in a wide variety of matrices, including blood, bones, tissue, water, soil, dust, air, and paint. One class examined whether soils from residential neighborhoods near a waste incinerator had significantly higher lead levels than average soils in Chicago. The initial data were inconclusive, so a subsequent class refined the analysis by expanding the sampling area and including housing units of similar age and type. A third class then looked more specifically at sites downwind of the incinerator. Joe Gardella, at the State University of New York–Buffalo, has developed a

program in which students examine environmental concerns created by the close proximity of industrial sites to residential neighborhoods (www.acsu.buffalo.edu/

~gardella). One goal is to use the resources of the university to foster cooperation among community residents and industry and government representatives.

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An upper-level chemical analysis course brings together multidisciplinary teams of chemistry, chemical engineering, environmental studies, geology, geography, and civil engineering majors to work on the problems. These projects have included analyses of metals and organic species in soils, and personal air sampling studies of residents. Wilbert Hope and Leon Johnson at Medgar Evers College have their students analyze ambient urban air in a local Brooklyn neighborhood for chemicals that affect human health (4). Some members of this community use mercury in their homes for religious practices; thus, elevated levels of mercury have been found in these homes. (However, the amounts have been below the limit established by the Occupational Safety and Health Administration.) In another project, students measured the levels of aldehydes and ketones in a neighborhood furniture store, as well as the concentrations of volatile organic compounds and nitrate in particulate matter from homes in the community. Tom Werner and co-workers at Union College, in conjunction with a local Trout Unlimited chapter, have their students measure important chemical constituents of local stream water. The data collected are added to a growing database aimed at long-term monitoring and assessment (5). By selecting new streams and different analytes, as well as developing longitudinal studies and sampling at different times of the year, Werner keeps the experience fresh for students and instructors alike. Preetha Ram at Emory University has a similar effort in which students work with the Upper Chattahoochee RiverKeeper, an environmental advocacy group, to monitor the water quality of the river (6). The class collaborates with the staff of the Georgia Environmental Protection Division and visits their lab during the term.

Outcomes Instructors who have developed community-based analysis projects cite a number of benefits: The students see the relevance of the experiment and appreciate the connection between analytical chemistry and the world they live in; the increased interest leads students to spend more time in the lab and commit more

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time to the course; and the community connection inspires students to perform accurate analyses and validate the results. In short, students tend to assume more responsibility for their own learning. Community-based environmental projects often yield a certain degree of uncertainty and complexity. Many of them cannot be completed in one semester; therefore, data from one year can be used to refine the project the following year. Although effective communication among students and community members is critical during the design and execution of the project, communicating the final results between the two groups can present special challenges. Community members may need to understand aspects of uncertainty in data and the statistical significance of the results, especially if the findings are inconclusive and more study is required. In the case of the mercury analysis, communicating the results required sensitivity toward the religious beliefs of the participants (4). Analyses performed by commercial laboratories are expensive, so the data generated by students benefit the community. In some instances, the community benefits have led to articles on the programs in local newspapers. In at least one case, significant numbers of students routinely volunteer for further community activities after completing the course (3). The involvement of community groups also creates some logistical constraints. The class is not a commercial laboratory, so turnaround times on analyses might be slower than community members expect, as they may not understand that samples need to be collected and provided within a time frame that accommodates the course schedule. Community members may expect too much from one class. They may have a difficult time appreciating concepts like significance and confidence limits and their impact on a researcher’s ability to draw definitive conclusions. These challenges make the real-world experience all the more valuable for the students.

semester, analytical chemistry course contact a local elementary, middle school, or high school instructor and arrange to teach a classroom lesson (7 ). The course is offered to nonchemistry science (primarily biochemistry) majors, and one goal of the assignment is to encourage more science majors to consider careers in teaching. After contacting the teachers, the students usually meet with them in small groups to discuss the project in more detail and arrange a date to deliver the lesson. Students also submit 500-word progress reports at approximately monthly intervals to ensure that they remain on task. The repeat participation of many of the teachers speaks to the success of the program. On the basis of evaluations and comments, student participants are more likely to consider teaching as a career, think more about the role of teaching as a strategy for learning, and realize the important responsibility professional scientists have in developing the next generation of scientists. Community-based projects in analytical chemistry courses have positive benefits for everyone involved. Community groups often welcome the opportunity to work with college students on a project of mutual concern. They help the university foster good relations with the community and provide community members access to expertise that can help address significant issues. Most importantly, community-based projects provide exceptional learning opportunities for students. Thomas J. Wenzel is a professor at Bates College. Address correspondence about this column to Wenzel, Department of Chemistry, Bates College, Lewiston, ME 04240 (twenzel@ bates.edu).

References (1) (2) (3) (4)

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Instead of assigning a community-based project involving chemical analyses, Julian Tyson at the University of Massachusetts– Amherst has each student in his one-

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Wenzel, T. J. Anal. Chem. 1995,67, 470 A–475 A. Wenzel, T. J. Anal. Chem. 1999,71, 693 A–695 A. Fitch, A.; Wang, Y.; Mellican, S.; Macha, S. Anal. Chem. 1996,68, 727 A–731 A. Hope, W. W.; Johnson, L. P. Anal. Chem. 2000, 72, 460 A–467 A. Werner, T. C.; Tobiessen, P.; Lou, K. Anal. Chem. 2001,73, 84 A–87 A. Ram, P. J. Chem. Educ. 1999,76, 1122–1126. Tyson, J. J. Math. Sci: Collab. Explorations 2001,4, 71–83.