Contact Information

  • Michelle Douskey, Ph.D.
  • Lecturer in Chemistry
  • College of Chemistry
  • 307 Latimer Hall
  • UC Berkeley, CA 94720-1460
(510) 643 - 9475

Dose Makes the Poison: Estimating the Relative Ecotoxicity of Various Biofuels

Laboratory Procedures (PDF)

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This experiment is intended to measure the effect of chemicals used in alternative fuels on plant germination. Students will learn about toxicity and its quantification, LD50 values. To test the toxicity, students will put seeds into petri dishes with filter paper soaked with the biofuel of interest. In the second lab period they will count the number of seeds germinated and measure their root lengths as an indicator of toxicity.

This item is part of a 3-experiment series on biodiesel synthesis, toxicity, and efficiency. Students will react vegetable oil to form their own biodiesel before testing its toxicity and efficiency.

Students had a chance to learn about real-world applications of chemistry and environmental health and safety by testing a compound they created themselves against other fuel sources that they hear about in the news.

This design of this laboratory exercise was inspired by The dose makes the poison: Measuring ecotoxicity using a lettuce seed assay submitted to GEMs by Irv Levy (Gordon College) in 2008.

Summary prepared March 2012 by Swetha Akella at the UC Berkeley.


Douskey, M. Dose Makes the Poison: Estimating the Relative Ecotoxicity of Various Biofuels, College of Chemistry, UC Berkeley, 2012

Category Descriptors

Chemistry Concepts
  • Biofuels
  • Qualitative Analysis
  • Toxicology
Laboratory Techniques
  • Biological Assays
Green Chemistry Principles
  • Analyze in Real-Time to Prevent Pollution
  • Design Safer Chemicals and Products
Chemistry Subdiscipline
  • Environmental Chemistry
Target Audience
  • Colleges/Universities
  • Original Contributions - unpublished