Fertilizers, Pesticides and Human Health - Math Lessons

Mathematics provides support in understanding parts per million, an important topic for understanding toxicity in human health. Other topics addressed in the math strand are: Calculating Parts per Million, Measures and levels of toxicity..

Standards addressed by this unit are available on the individual lessons. To reach a lesson, just click on its title. To see connecting lessons in science, social studies, and language arts return to the ‘Cultures and Cycles’ unit page.

Each big idea is addressed by a learning cycle. At the completion of each big idea’s learning cycle students should be able to answer the corresponding question. At the end of the unit, the students will be able to apply their new scientific understanding to the Major Project where they provide a public service message that is checked in advance by local public health officials for accuracy.


Lesson Title & Description
Students will:
Class period & week
Students develop formulas to explain how small levels of contaminants build up and become detrimental to species higher in the food chain.
Use real data to create an algebraic equation.

Week 4

How Small is It?
Activities to help students visualize how small a concentration of one part per million represents by creating physical representations of one ppm. Parts per million is an important concept in toxicology.
Create a visual representation of what the concentration of one part per million means.
Week 5
Calculating Parts per Million: Do We Have a Problem Here?
Students will use unit analysis to calculate parts per million represented by given ratios, and in a given scenario, determine whether the concentration of contaminants is sufficient high to warrant health officials closing a lake.
1. Calculate ppm and ppb by using unit analysis when given a ratio of amounts

2. Determine in ppm what constitutes a health risk for a particular toxin given data
Week 6
The Portion is the Poison
Students will calculate the amount of everyday food products or liquids that would need to be consumed to become toxic. 
Use unit analysis to check measurement computations.
Week 7
An introduction to the Natural Log (ln)
To encourage students’ comprehension of the dose response principle, an introduction to what the “natural log” (ln) is and how it behaves is recommended. This will help students to create and analyze a dose response graph.

1. Define a log as the inverse of an exponentials.

2. Explain the benefit of a natural log for biologists.

3. Calculate the natural log of a number.

4. Plot a logarithmic graph

Week 6


PULSE is a project of the Community Outreach and Education Program of the Southwest Environmental Health Sciences Center and is funded by:

NIH/NCRR award #16260-01A1
The Community Outreach and Education Program is part of the Southwest Environmental Health Sciences Center: an NIEHS Award


Supported by NIEHS grant # ES06694

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Last update: November 10, 2009
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