Lab-Aids: Organically Grown? (Testing for Simulated Pesticide Residue)

• Grades: 6+
• Number of Students: 32

In this investigation, students will use a chemical test in order to determine whether fruit samples have been treated for any simulated pesticides. Based on their test results they grapple with the further question of which sample(s) could potentially be marketed as organic.

Scientific Concepts:

• Pesticides, chemicals used to control insects and other pest organisms, are used in production agriculture.
• All pesticides must be approved by the USDA.
• Low levels of pesticide can be detected using chemical tests.
• Organic production uses several classes of pesticides approved by the USDA.

Product Includes:

75 pieces of dried apple
80 small plastic tasting cups
8 stir sticks
4 dropper bottles of “Pesticide 1” Indicator
4 dropper bottles of “Pesticide 2” Indicator
4 dropper bottles of “Pesticide 3” Indicator
1 60-mL bottle of “Pesticide” Solution A
1 60-mL bottle of “Pesticide” Solution B
1 60-mL bottle of “Pesticide” Solution C
32 Student Guides
1 Teacher's Guide
1 SDS (Safety Data Sheet) packet

Classroom Planning: 

Number of groups:  maximum 8 groups per class
Number of students: maximum 32 (8 groups of 4 students)
Number of classes: sufficient materials for 2 classes