Quantitative Analysis of Heavy Metals in Children's Toys and Jewelry: A Multi-Instrument, Multitechnique Exercise in Analytical. Chemistry and Public Health

For most chemistry curricula, laboratory-based activities in quantitative and instrumental analysis continue to be an important aspect of student development/training, one that can be more effective if conceptual understanding is delivered through an inquiry-based process relating the material to relevant issues of public interest and student career trajectories. Laboratory experiences that actively engage students in this manner can be difficult to identify and execute. A special topics, project-based laboratory module is presented here that utilizes multiple techniques and instruments to investigate toxic metal content (lead, cadmium, and arsenic) in children's toys and toy jewelry. The module effectively illustrates a considerable number of fundamental and advanced quantitative analysis principles including sample digestion, Beer Lambert law, calibration curve, and standard addition analyses, as well as instrumental analysis considerations of atomic absorption spectroscopy including atomization efficiency (e.g., flames vs furnaces), matrix modifiers, and nondestructive spectroscopy. Module effectiveness stems from the illustration of critical chemical analysis principles in the context of projects with student-directed hypotheses and experimental results that are clearly relevant to the interface of basic science, medicine, and public health: primary career interests for a significant number of undergraduates in the physical and life sciences.