Due to the growing concern on the adverse effects on human and environment, more attention in the non-chemical pest control methods is gaining. One of the so-called ‘sustainable’ control practice is to physically freeze the insect and arthropod pests. Aerosol formulation uses propellant gas which is liquefied by pressure, and it lowers the temperature when sprayed by the volume expansion. Using this phenomenon, several ‘freeze spray’ products in South Korea and Japan are commercialized. Nonetheless, unlike other traditional aerosol insecticides, the lack of insecticidal substances in these freeze products allowed them to circumvent legal inspection and registration, no efficacy test result is required in commercialization. In the present study, we examined the insecticidal activity of the freeze spray products against German cockroaches and the housefly in the laboratory condition as well as semi-field tests. The temperature of discharged center mass was –40-45℃, but it had relatively small active range (about 3 cm) which required pinpoint application of the product. Moreover, at least 30 sec and 12 sec of direct contact at 30 cm was required to exhibit >90% of mortality in the cockroaches and houseflies in the lab-based tests, respectively. Semi-field tests indicated an average of 15.8 g and 22.0 g were required to spray to knock down the freely-moving cockroaches and houseflies, respectively. Further utility of the freezing products is discussed.

• Seongbin Kim(Department of Applied Biology and Chemistry, Seoul National University) Corresponding author
• Jun-Hyung Tak(Department of Agricultural Biotechnology, Seoul National University, Research Institute of Agriculture and Life Sciences, Seoul National University)