Pesticide products sold over the counter to kill bedbugs may cause more harm than good, according to Dini M. Miller, Ph.D., Entomologist for Virginia Tech. At best, these products are ineffective, at worst; they may get people and pets ill. The best way to eliminate bedbugs is to hire a pest management professional, advises Cornell University.
Lack of Contact with Bedbugs
Bedbugs need to come in contact with the insecticide in order to be poisoned. But since bedbugs have nearly flat bodies, they can hide in cracks and crevices in walls, floors or furniture and wait until the insecticide loses its potency. Even insecticide “bombs” or aerosol foggers only coat the surface of objects with insecticide and do not penetrate into places where bed bugs hide. These “bombs” are highly flammable and have been known to suddenly explode.
Multiple treatments of these products fail to kill bedbugs. But aerosol foggers coat the room and objects with a layer of insecticide that may sicken pets and people because they are far more likely to come into contact with the residual pesticides than the bedbugs.
Pesticides that could kill bedbugs decades ago, such as pyrethroids, now do not work. Over the counter pesticides consist of pyrethroids. Unfortunately, bedbugs are increasingly becoming resistant to pyrethroids. Pyrethroids attack the bug’s nervous system and cause paralysis. But bedbugs protect their nerve cells with genes that break down toxins from pyrethroids into harmless chemicals, according to Ohio State University. Bedbugs that survive pyrethroid exposure pass this resistance to their offspring.
Adult bedbugs survive up to one year between meals, according to Cornell University. Bedbug larvae, called nymphs, can only survive a few months. But this is long enough to wait out a pesticide treatment. If only one room is treated or one apartment in a large building, then bedbugs can scamper from the treated area to untreated rooms and apartments, infecting them. Eventually, they return to the originally treated area.
All rooms in a home or building need to be treated simultaneously, although this is still not guaranteed to kill all of the bedbugs, especially eggs. Only professional strength insecticide sprays can kill eggs. These insecticides are often licensed, depending on what state, province or country one lives in.
Alternative to OTC Products
Cornell University states that it takes two or more treatments by pest control professionals in order to eliminate bedbug infestations. But even insecticides cannot do the job alone. Homeowners must vacuum floors, baseboards and furniture; all clothes, bed linens, small pillows and machine-washable stuffed animals washed in hot water and large pillows placed in a hot clothes dryer. Just cleaned items need to be placed in plastic bags until the infestation is considered over.
All cracks in furniture, walls or floors need filling in so bedbugs cannot find hiding spaces and females cannot find spots to lay their eggs. Beds and sofas may not have to be tossed unless this is recommended by an exterminator.
Virginia Department of Agriculture & Consumer Services: “Bed Bug Treatment Using Insecticides.” Dini M. Miller, Ph.D.
Cornell University New York State Integrated Pest Management: FAQ List for Bed Bugs
University of Kentucky: “Bed Bugs.” Mike Potter; August 2008. http://www.ca.uky.edu/entomology/entfacts/ef636.asp
National Public Radio. “Bedbug Genome Reveals Pesticide Resistance.” Jon Hamilton; January 19, 2011. http://www.npr.org/2011/01/19/133057071/bed-bug-genome-reveals-pesticide-resistance (Describes findings by Ohio State University.)