A new study shows that a common variety of consumer-grade insecticide sprays have “little to no value” in eliminating German cockroach infestations.
The study was published in the August edition of the Journal of Economic Entomology.
Residual insecticide sprays are designed to be applied to surfaces where roaches are likely to appear, so they will be killed when they contact with them. The study, conducted by researchers at the University of Kentucky and Auburn University, shows that the residues of these products have little effect on the roaches. German roaches are a primary species that infest homes and buildings around the world.
During their tests, they used consumer-grade liquid and aerosol sprays that are made with pyrethroid insecticides. Here are some of the results:
• Less than 20% of German roaches died after being exposed to these products for 30 minutes.
• When they confined the roaches to these sprayed surfaces, it took most products 8 to 24 hours to kill the roaches. Other products took up to five days to achieve results.
They also tested these products by applying them to a variety of surfaces, such as on painted drywall, ceramic tile, and stainless steel. Testing showed that these products performed significantly worse when applied on drywall. This suggest that porous surfaces may have a significant impact on product efficacy.
German Roach
(Blattella germanica)
Another factor likely to contribute to the poor performance of residual spray products is that roaches are unlikely to come to rest for extended periods on surfaces treated with insecticides. This is because roaches are usually on the move, and they may be repelled by these insecticides.
The researchers recommend that if consumers want to do their own roach control, their best options would be to use gel or liquid baits. These baits work by attracting the roaches to a food source that is laden with a slow-acting insecticide.
Have a roach problem that you don’t want to handle yourself? Call us at (949) 631-7348 and we will be happy to set up an appointment at your convenience.
