Search for Science Fair Projects

1000 Science Fair Projects with Complete Instructions

Botany Science Fair Project

Testing Toxicity with Lettuce Seeds

Testing Toxicity with Lettuce Seeds | Science Fair Projects | STEM Projects
Are you curious about how different concentrations of salt can affect lettuce seeds? Let's find out by conducting a reference toxicity test. We'll mix up different concentrations of salt and then measure the response of the lettuce seeds.


The hypothesis is that the lettuce seeds will respond in a predictable manner to varying concentrations of salt.

Method & Materials

You will treat the lettuce seeds in a bleach solution, label a series of beakers with different concentrations of salt, add the appropriate test solution to each petri dish, add 5 lettuce seeds to each dish, place the dishes in a plastic bag, incubate the seeds in the dark for 5 days, and then count how many seeds have germinated and measure the root length of each.
You will need lettuce seeds, deionized or distilled water, a 0.2M NaCl solution, 9-cm petri dishes, 7.5-cm paper filter, bleach, and a plastic bag.


After conducting the experiment, we can conclude that the lettuce seeds responded in a predictable manner to varying concentrations of salt. The most interesting observation was that at some threshold concentration, all of the test organisms were killed.

Why do this project?

This science project is interesting because it demonstrates how a simple organism can be used to test the toxicity of a compound.

Also Consider

Experiment variations to consider include testing different compounds and using different concentrations of the same compound.

Full project details

You can find additional information and details for this science fair project here. Have fun exploring!

Related video

Hey there! Here are some awesome videos about this science project that we think you'll really like. They're not only super fun, but they'll also help you learn more about the science behind the project. So sit back, relax, and get ready to have some fun!!
Share this Science Project:

Related Science Fair Project Ideas

Fertilizer and Plant Growth
Does too much or too little fertilizer slow down plant growth? Find out in this science project!
Planting Companions
Plant different types of plants together to see if they help each other grow better!
The Effects of Fertilizer on Plant Growth
Ever wondered how fertilizer affects the growth of plants? Find out by conducting an experiment with radish plants and different concentrations of fertilizer!
Share this Science Project: