Every school or district should develop a list of pesticides approved for use on school property. Criteria for selecting pesticides is listed below. If you are using contracted pest control, ensure that they only use approved pesticides from your list. This can be determined in the contract.
Here are a few examples of approved pesticides lists from other school distrust around the country:
How to Select a Pesticide for an IPM Program
When contemplating the use of a pesticide, it is prudent to acquire a Safety Data Sheet (SDS) for the compound. SDS forms are available from pesticide suppliers and contain some information on potential hazards and safety precautions.
Globally Harmonized System (GHS). Starting in June, 2015, all pesticides will have to follow a new format for labeling. Additionally, MSDS (material safety data sheets) sheets will now be called SDS (safety data sheets) and will also be in a standardized format. This new format of labeling uses pictographs to communicate the hazard potential of each chemical product. These new pictogram categories could help you select products that have reduced acute and long-term/chronic toxicity. Please see OSHA's video tutorial on the Globally Harmonized System here.
The following criteria should be used when selecting pesticide: safety, species specificity, effectiveness, endurance, speed, repellency, and cost.
This means safety for humans (especially children), pets, livestock, and wildlife, as well as safety for the overall environment. Questions to ask are as follows:
- What is the acute (immediate) and chronic (long-term) toxicity of the pesticide? Acute toxicity is measured by the "LD-50" which is the lethal dose of the pesticide required to kill 50% of the test animals (measured in milligrams of pesticide per kilogram of body weight of the test animal). The higher the LD-50, value, the more poison it takes to kill the target animals and the less toxic the pesticide. In other words, high LD-50 = low toxicity. Chronic toxicity refers to potential health effects from exposure to low doses of the pesticide for long periods of time. Chronic effects can be carcinogenic (cancer-causing), mutagenic (causing genetic changes), or teratogenic (causing birth defects).
- How mobile is the pesticide? Is the compound volatile, so that it moves into the air breathed by people in the building? Can it move through the soil into the groundwater? Does it run off in rainwater to contaminate creeks and rivers?
- What is the residual life of the pesticide?
- How long does the compound remain toxic in the environment?
- What are the environmental hazards listed on the label?
- What are the potential effects on wildlife, beneficial insects, fish, or other animals?
The best pesticides are species specific; that is, they affect just the group of animals or plants you are trying to suppress. Avoid broad-spectrum materials that kill many different organisms because they can kill beneficial organisms that keep pests in check. When broad-spectrum materials must be used, apply them in as selective a way as possible by spot-treating.
A quick-acting, short-lived, more acutely-toxic material might be necessary in emergencies; a slow-acting, longer-lasting, less-toxic material might be preferable for a chronic pest problem. An example of the latter is using slower-acting boric acid for cockroach control rather than a quicker-acting but more toxic organophosphate.
Does the pesticide repel certain pests like cockroaches or bed bugs, or can bugs walk on top of it and not be repelled?
Is there known resistance among an insect species to the pesticide you are thinking of using. Research the active ingredient (not the product name) or group of pesticides and determine if there is reported resistance.
This is usually measured as cost per volume of active ingredient used. Some of the newer, less-toxic microbial and botanical insecticides and insect growth regulators may appear to be more expensive than some older, more toxic pesticides. But the newer materials tend to be effective in far smaller doses than the older materials-one container goes a long way. This factor, together with their lower impact on the environment, often makes these newer materials more -cost effective.
Least-Toxic Chemical Controls
The health of school residents and long-term suppression of pests must be the primary objectives that guide pest control in school settings. To accomplish these objectives an IPM program must always look for alternatives first and use pesticides only as a last resort. Many people are familiar with insecticides such as malathion, fungicides such as benomyl (Benlate), and herbicides such as 2,4-D. These and similar materials have engendered controversy over possible hazards they pose to human health and the environment. There are many other chemical products to choose from that are relatively benign to the larger environment and at the same time effective against target pests.