The dose makes the poison: Measuring ecotoxicity using a lettuce seed assay

Laboratory Procedures (PDF)

Author Contact: irv.levy@gordon.edu

Summary

The goal of green chemistry is the design of materials and processes that are inherently safer for human health and the environment. Currently, few undergraduate chemistry students are trained about toxicity of chemicals and even fewer have experienced the laboratory investigation of chemical toxicity. Here we present a laboratory experiment that enables students to measure ecotoxicity of different alternative starting materials used for the preparation of biodiesel. An assay patterned after standard EPA protocols is used to compare the ecotoxicity of methanol, ethanol, and isopropanol by these alcohols, effects on germination rate and root elongation of lettuce seeds. The experiment is simple, fast, inexpensive, reproducible and possible to perform with standard equipment available in most chemistry teaching laboratories. The link to the laboratory procedure includes post-lab questions and a data report form.

Summary prepared May 2008 by Soo Y. Kwon and Irvin J. Levy, Gordon College.

Category Descriptors

Chemistry Concepts

• Biofuels
• Measurement/Analysis
• Toxicology

Laboratory Techniques

• Biological Assays

Green Chemistry Principles

• Design Less Hazardous Chemical Syntheses
• Use Safer Solvents/Reaction Conditions

Chemistry Subdiscipline

• Environmental Chemistry

Target Audience

• Colleges/Universities
• Secondary Schools

Source

• Original Contributions - unpublished