S.K. McDonald, Bugwood.org
To teach about decision-making in pest management, many student activities are possible. Students can choose pest management situations they see in and around their own homes. Following the IPM steps and tactics, they can devise a strategy that includes the use of one or more pesticides. But which ones? Using actual labels from household chemical products, information charts on pesticides and web research, students can lead discussions or write research reports. This activity generates critical thinking and interesting discussions. Students learn that, in the end, they still have to make their own INFORMED decisions and there is no "one" answer.
1. Understand that pesticides are all different.
2. Learn what some of the key active ingredients are in pesticides
3. Understand factors in reducing risk of toxicity and exposure to themselves.
4. Learn decision-making skills needed in pest management decisions
Teacher: Read background section on chemical use.
1. Present your choice of background information on pesticides & pesticide issues.
Discuss and answer student questions. Review steps and tactics of IPM.
2. Then pose a scenario to the students, such as
"There are "bugs" on your mom's roses. She knows you have taken an IPM unit
in school and asks you to help figure out what she should do about the bugs."
3. Ask students what IPM steps they would take to "solve" the problem.
4. Give students (or groups) some different pesticide options to discuss & choose between.
Use actual products available (unopened) so students can study the labels as they are
presented on the product. Be sure to include a variety of chemical classes, formulations, signal words and spectrum of activity.
5. Provide tools (handouts, websites) for investigating details of product options.
6. After groups research and discuss options, have students present their choices and explain the rationale for those choices.
Kinds of questions you can use to help students get started:
- Labels of pesticides as they appear on the product (these can be xeroxed or obtained from the companies that produce the product)
- Preparation via lecture
- Will these products actually control the pest I have? (Am I sure I know what the pest is??! Do I know its life cycle?)
- Efficacy; short or long term control?
- What are the active ingredients?
- What are the relative acute toxicities to humans by signal word? By actual LD 50s?
- What are the risks of exposure due to formulation?
- What precautions do the labels tell you? How, exactly, would you apply the products safely?
If you wish, other issues can be introduced for discussion such as long-term toxicity, persistence in the environment, biomagnification, whether or not the properties of the pesticide make it a potential problem for water contamination and so on.
Table: Toxicity Categories for Labeling Pesticides
LD50 for 150 lb. Human
|Oral LD50 in Common Measuring Units |
|I||Danger||0-50||0-200||Taste - teaspoon (tsp)|
|III||Caution||500-5000||2000-20,000||1 oz. pint|
|IV||Nnne||over 5,000||over 20,000||over a pint|
Homeowner Pesticides: How to Choose?
Not all pesticides are created equal!
Did you know?
Homeowners use more pesticides, on a pound per acre basis, than farmers do.
Ask yourself - is it really necessary to use a pesticide, or is there another way to control the pest?
Every pesticides has one word on the label that tells you about how toxic it is.
Look on the package front for the "Signal Words": Caution (least toxic), Warning, or Danger (most toxic).
Risk of pesticides=Exposure x Toxicity.
Reduce risks of pesticides to yourself and others by choosing products least likely to get on/in you, wear protective gear and choose least toxic products.
If some is good, more is not better!
Use pesticides at recommended rates, not double or triple. This only increases your chances of exposure, increases contamination of the environment and helps pests become resistant to pesticides.
Be a discriminating consumer when buying pesticide products.
- How a chemical is "packaged" can make a difference in toxicity.
The same chemical in liquid concentrate, dust, ready-mixed or covered baits will have differing toxicities. This is because the Active Ingredient (poison) is in different concentrations and the type of formulation determines the likelihood of pesticides being breathed or contacting the skin.
- Understanding pest biology can tell you about which product may be the most effective.
Spraying worker ants in your kitchen contaminates the kitchen and is not effective because the source of the ants has not been eliminated. A product in covered bait formulation that will be carried back to the ant nest and kill the queen is both safer and more effective.
- Read labels carefully and decide if you want to use the product in question.
- Specific pests controlled (is that what you have?)
- Special precautions about toxicity to animals, bees?
- Will you realistically be able to use the product and not breathe it or get it on you?
For more information about pesticides, contact Penn State Pesticide Education 814-863-0263, PA IPM Program 814-865-1896 or the extoxnet website