QUESTION:

I have a VERY sensitive account that has a problem with roaches and has had this problem for many many years. It is a medical research facility that raises animals and so there are lots of conducive conditions that have made it very difficult to eliminate the problem. We are presently using pyrethroids (bifenthrin) as well as Gentrol. We have wanted to use Transport but the management at the facility does not believe that pyrethroids are the answer and feels that acetamiprid is too new of a product with too little research to be able to be approved by the management for use. We have used baits in the past but with the animal food and feces that are in the building the baits did very little good. There are many rooms that we are not allowed to go into because animals occupy these rooms making a complete treatment even more difficult. Recently we met with some of the main people and they want us to use "stronger" products as they don't believe that pyrethroids are the answer. What suggestions do you have in regards to products that may have a greater efficacy against the German roach that are not pyrethroids? What about nicotinoids or OP's? Thanks.

ANSWER:

Wow. I wonder what I am going to come up with that is useful to you. A few observations first on your comments, and the first is with respect to their impressions about pyrethroid insecticides. I suspect they are aware that some scattered populations of German roaches have shown "resistance' to pyrethroids, but resistance does not mean immunity. It means only that it takes more of the active ingredient to kill the roaches, and this is accomplished either by increasing the concentration they are exposed to but leaving the contact time the same, or staying with the same concentration but finding a way to increase the length of time the roaches are in contact with it. More on that later I think. But, pyrethroids definitely are capable of killing German roaches, and suggesting that a "stronger" toxin is needed is silly.

How we define "strong" or "powerful" is misunderstood, and over the 3+ decades I have been in this industry we have witnessed a marvelous evolution in what we use, from the Category 2 (moderately toxic) organophosphates and chlorinated hydrocarbons to the Category 3 and 4 (slightly toxic) pyrethroids and newer chemical families. The pyrethroids are not stronger toxins, but instead they are effective on insects at much lower concentrations of the active ingredient. Our industry manufacturers learn more and more about how to attack insects effectively while using less toxic substances and less of them. So much for that soap box.

Since this facility has apparently continued to have this roach problem for many years, it sounds like it is time to change the game plan. As someone once said, "the definition of  insanity is continuing to do the same thing while expecting a different result", and clearly insecticides have not been the complete answer here. (I really like that adage). Frankly, I'm surprised they allow you to use what you have so far, as research facilities sometimes are very nervous about exposing test animals to any kind of contaminant or toxin in any manner, for fear it might alter some test results later. But, don't tell them that. It also may be necessary for this customer to accept that NO place in the facility can be off limits to you. If they have roaches you need to be able to inspect and deal with every place where the roaches may be living, or the problem is going to continue.

We accept that old adage that roaches require 3 things for their survival - food, water, harborage. It sounds like food and water are going to be difficult to control, so how about spending your time eliminating their harborage? The German roach is not likely to change 350 million years of behavior by suddenly deciding it does not need to get into dark crevices and voids. Every access point that you close to them means that much less harborage they have available, and this stresses the heck out of a cockroach. Instead of injecting insecticide into that crevice on the next visit can you instead inject caulking, and eliminate that crevice forever as a roach harborage point? I know this sounds pretty simplistic on my part, but ultimately perhaps it will be the answer, and the years of injecting insecticides have not worked, so time to change the game plan. Filling every possible crack, crevice, and hole will sound like an impossible task, but if it's taken one wall at a time you will suddenly realize it is getting accomplished.

There must be plenty of hollow voids for the roaches to hide in as well, and perhaps these can be injected with an inorganic dust (diatomaceous earth, silica gel dust) to provide long lasting kill of any roaches that find their way in. These also are essentially non-toxic to any test animals there. Hopefully the insecticides you currently use are not being applied as the good old "base board" spray, but instead you are carefully injecting the sprays directly into the crevices and voids where the roaches hide. Treating bands that the roach runs across just do not get the contact time needed to get a lethal dose of the active ingredient into the roach, but placing the material where the roach sits on it all day long gives you a better chance. This also keeps the insecticide away from any human or animal contact and allows it to last longer. I also hope that fogging is not part of the repertoire, as this is ineffective for German roach control.

I know that changing the way your customer behaves is very hard to do, but they are going to have to buy into this process too, and stop thinking that insecticides are the total answer. We've never really had the magic wand that so many customers think we have in the tool box. By the way, the OP's (organophosphates) were taken from us 10 years ago, so this is not an option. Neonicotinoids include products like Optigard, Transport, and Arena, and these are certainly excellent materials for German roaches, so if changing the insecticide makes the customer happy then give it a try, assuming the product you choose is properly labeled. Plenty of other non-pyrethroids also exist now, such as Phantom, Advion, Alpine, and the various imidacloprid products. It has always been good policy to "rotate" your product use from one chemical family to another to avoid the chances of resistance developing.

But, I would love to see an increased emphasis on non-chemical approaches here, and an elimination of every possible access to harborage that you can accomplish. Long term this may be the best answer.

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