[Technically Speaking] Getting The Most Out Of Labels

I have had several discussions this past year regarding labeling and pesticide use that are worth sharing. If there is one resounding statement that everyone in our industry knows, it is, "The label is the law." However, that being said, there is some latitude that the U.S. Environmental Protection Agency permitted in its early days and it was promulgated in what the Agency termed Pesticide Enforcement Policy Statements (PEPS). Several of these remain in effect today.

One of the most important of these statements addressed the use of a pesticide to treat for a pest that is not listed on the label. This has really come to the forefront in the treatment of bed bugs, since many pesticide manufacturers dropped this pest from the typical list of pests placed on their product labels. This is understandable since bed bugs virtually disappeared for the past 40 years as a result of baseboard spraying and an array of very effective products.

TREATMENTS FOR BED BUGS. All of that changed in the past 10 years with more directed pesticide applications, widespread use of baits and the loss of products like chlordane, lindane, dichlorvos, diazinon and chlorpyrifos. With the explosion of bed bug infestations over the past two years everyone has been scrambling to find effective strategies and products to solve this problem.

We learned early when treating for bed bugs that products having this pest on the label were not necessarily the best products to use. For instance, most of the pyrethroids caused the bugs to run. So we began looking for products that were non-repellent, e.g., carbamates organophosphates and chlorphenapyr. The only problem was most of these products do not have bed bugs on the label.

The good news is that the PEPS permits a product to be used for a non-target pest, providing the following conditions are met:

• The application site is on the label. Check this carefully because this not only means indoors in apartments and homes, but check to see specifically where in these structure the product can be used, e.g., cracks and crevices, spot and/or broadcast applications. The label may be moot on applying the product to bedding or furniture and therefore could not be used to treat those items.

• The use of the product is expected to control the unlisted target pest. For instance, the use of a bait to control bed bugs will not work because they can not feed on the bait products available today, thus this use would not be permitted.

• The use of the product for an unlisted target pest is not prohibited by the label.

• The use of a product for an unlisted target pest is not prohibited by state law or regulation.

All in all, the label and EPA give us some latitude to find a suitable product to deal with this type of problem.

MOSQUITO CONTROL. Another situation has come to the forefront with automatic pesticide dispensing systems for mosquito control. While this type of system has been around for almost 25 years, albeit installed in horse barns for fly control, the problem is what type of product can be applied with this equipment.

If you (like me) have spent any time looking at labels (and most of us have), we tend to be more focused on the final concentration, health issues, environmental concerns and sites of permissible application. We rarely think about the type of equipment we are going to use to apply the product. Rightfully so, since most labels are silent on that point. A few notable exceptions are termiticide labels and products that can also be applied as aerosols.

In determining the type of products to use in this type of dispersal equipment several questions need to be answered using the label:

• In this case we are dealing with mosquitoes — despite my earlier discussion and unless you have a great deal of experience in adult mosquito control, is the target pest (mosquitoes) on the label?

• Is the intended site of application on the label, e.g., vegetation, landscape plants, structure?

• Will the formulation and the labeled concentration work in the equipment?

• Does the label or state law or regulation prohibit this type of application equipment?

• Is there any risk that the application using this equipment will cause drift and/or contaminate surface/or ground water (if prohibited by the label)?

Typically, we have the ability to select the type of application equipment we want to use for most pesticide products.

Another PEPS allowed pesticide applicators to apply products at less than their labeled rate of application. This was more likely developed for the agricultural industry rather than the structural pest management industry. Some in our industry capitalized on this statement, i.e., some of those performing termite pretreatments. In effect, this allowed some companies to legally use less than labeled rates for termite pretreatments.

Fortunately, this ill-advised practice was corrected when EPA required manufacturers to mandate minimum application rates on termiticide labels for pretreatments. Unfortunately, they did not go far enough and require this same standard for post-construction applications.

Regardless of what the target pest is, it is not a good practice to use less than the labeled rate. In insects like cockroaches, flies and mosquitoes this has led to resistance development. In other cases, lower rates shorten persistence (termites) or simply do not work.

Isn’t it good to know we are occasionally given the opportunity to think "outside the box?"

The author is technical director of American Pest Management, Takoma Park, Md. He can be reached at 301/891-2600 or rkramer@pctonline.com.