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BACKGROUND: Pyrethroids are synthetic insecticides with low mammalian toxicity and broad‐spectrum activity across insects. One major challenge with pyrethroids is their perceived repellency. This perception can influence decisions made by pest control operators, especially when insecticides are used to reduce insect entry into or movement within structures. One major indoor pest that has been repeatedly shown to be repelled by some pyrethroids is the German cockroach, Blattella germanica. However, most experiments evaluating pyrethroid repellency in the German cockroach have used end‐point assays, which do not provide information on the movement that led to the final position. Therefore, we evaluated the kinetic behavioral response of field‐collected German cockroaches to five pyrethroid‐based products and their active ingredients (A.I.) in open behavioral arenas using advanced video tracking software. In addition, in an effort to compare our free‐moving experiments with end‐point assays, we evaluated sheltering behavior using two‐choice harborage arrestment assays where German cockroaches were provided a choice between pyrethroid‐treated and untreated shelters. RESULTS: All pyrethroid‐formulated products and their respective A.I.'s failed to affect field‐collected German cockroach movement behavior in free‐moving assays, while positive controls (DEET, corn mint oil) resulted in reduced time spent by German cockroaches in treated areas. However, despite their willingness to move over pyrethroids‐treated surfaces, field‐collected German cockroaches displayed a reduced propensity to arrest on pyrethroids treated tents. CONCLUSION: While most pyrethroids/pyrethroid‐formulated products affected German cockroach arrestment, pyrethroids and pyrethroid‐formulated products failed to change German cockroach movement behavior in free‐moving assays. These results indicate the pyrethroids tested act as contact irritants rather than true‐spatial repellents on field‐collected German cockroaches. This distinction is critical to refining pest management strategies involving pyrethroids. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND The global prevalence of Cimex lectularius infestations has challenged current intervention efforts, as pyrethroid resistance has become ubiquitous, availability of labeled insecticides for bed bugs is limited, and non-chemical treatment options, such as heat, are often unaffordable. We evaluated representative insecticides toward the goal of developing a novel, ingestible liquid bait for hematophagous arthropods. RESULTS LC50 values were estimated for adult males and first instar nymphs of an insecticide-susceptible strain for abamectin, clothianidin, fipronil and indoxacarb, after ingestion from an artificial feeder. LD50 values were calculated based on the ingested blood volume. Ingested abamectin, clothianidin and fipronil caused rapid mortality in both life stages. Fipronil was ∼43-fold more effective by ingestion than by topical application. Indoxacarb and its bioactive metabolite decarbomethoxylated JW062 ( DCJW) were ineffective at causing bed bug mortality even at concentrations as high as 1000 ng mL−1 blood. CONCLUSIONS Fipronil, clothianidin and abamectin have potential for being incorporated into a liquid bait for bed bug control; indoxacarb and DCJW were not effective. Bed bugs are a good candidate for an ingestible liquid bait because systemic formulations generally require less active ingredient than residual sprays, they remain contained and more effectively target hematophagous arthropods. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]