A habitation investigation of cockroaches in a building in Hiroshima Prefecture was conducted between July 2010 and February 2011, and the following three species were captured by sticky trap: Brown cockroach (Periplaneta brunnea Burmeister; n＝399), German cockroach (Blattella germanica Linne; n＝1170), and Smoky-brown cockroach, (Periplaneta fuliginosa Serville; n＝6). P. brunnea individuals were found on the first to the third basement level; B. germanica, on the first to the third basement level and from the fifth level to the roof; and P. fuliginosa, on the roof and the third basement level. One P. brunnea and 881 B. germanica were captured in the restaurants, and 40 P. brunnea, 190 B. germanica, and three P. fuliginosa were captured in the pantry (SK (slop sink), laundry, and refrigerator). Therefore, B. germanica was the dominant species. 219 P. brunnea and 52 B. germanica were found in the backyards (service corridor), and one P. brunnea and two B. germanica were found inside the vending machines. Three P. brunnea, three P. fuliginosa, and 15 B. germanica were captured in the restrooms. Only 35 P. brunnea were found in the freight-handling area, and one P. brunnea and two B. germanica were found in the machine room. 15 P. brunnea and 27 B. germanica were captured at the garbage collection point. As for seasonal prevalence, a few P. brunnea adults and nymphs were captured between the early summer and early fall, but no adults and a few nymphs were captured in the winter.

The insecticidal efficacy of silica-gel powder against the German cockroach was remarkably affected by the particle size; the smaller size was more effective. The smallest size, as small as 470 mesh, produced good efficacy when applied at a rate of 3 g/m² or more on the floor of a plastic arena against a susceptible strain and a field-collected colony that was highly resistant to organo-phosphoric insecticides. A particle size of 30 or 40 mesh sieves did not kill cockroaches. The 470 mesh silica-gel powder did not increase weight when exposed to room conditions of 26°C, 70％ RH for seven days, and the exposed 470 mesh silica-gel powder remained effective. When 470 mesh silica-gel powder was applied in a limited corner of the arena, the mortality was high in an inner circumference application but low in the center or in one side corner due to repellent behavior. Cockroaches exposed to 470 mesh silica-gel powder were dehydrated. The 470 mesh silica-gel powder did not show good efficacy against the larvae of the brown cockroach when applied at a rate of 10 g/m². Other minerals passed through 200 mesh sieves, such as Kanuma pumice and Sakurajima volcanic ash, also killed German cockroaches when applied at the rate of 10 g/m².

Insecticide residues of 20% propetamphos MC were quite variable depending on the test materials. Ceramic tile was highest, followed by plywood, aluminum, cork, and chlorinated vinyl, when soaked for five minutes in a diluted solution. The MC particles were stable for two months or more on the surface of the test materials. The initial kill effect of the chemical was very high in each material, showing 100% mortality up to 320 times dilution against a susceptible strain of both sexes of the German cockroach, but 80 times dilution was needed for a good kill against a field-collected colony of the same species. There were no differences up to 320 dilution in each material. However, with 640 dilution or more, cork and aluminum decreased in mortality. The residual efficacy of the MC formulation was very high with 40 times dilution, indicating a 100% kill effect for four months in every material; 80 times dilution in cork was not sufficient whereas other materials maintained a good effect.

Insecticide-impregnated nets exhibited good killing effect against a susceptible strain of the German cockroaches in a non-choice test, but were not effective against a field-collected colony in the same test. However, bait consumption of field-collected German cockroaches was not influenced when baits were put at the center of the net. When a harborage made of folded impregnated net was placed with untreated net separately in the same arena, the field-collected cockroaches deposited few feces on the insecticide-impregnated net in comparison with the untreated net due to repellent activity. When the net was stuck to the inside of the harborage, the cockroaches were reluctant to enter it, but they stayed and deposited many feces in the non-treated net harborage. Putting impregnated nets into the cracks and crevices of walls or coiling with nets around stands of food processing lines might effectively prevent cockroach infestations.

The alimentary canal contents of captured Smokybrown and Japanese cockroaches were analyzed. Cockroaches were collected with sticky traps in open spaces close to a high-rise building, in tree hollows in an urban park, and in planters around a warehouse in Minato-ku, Tokyo, from June to December 2011. The results were confirmed as piece of cockroach, egg of parasite (Thelastomatida), pieces of plants, and fungi. In arthropoda except the cockroach were pieces of ants, springtails (Hypogastruridae: genus Xenylla) and mites (Cryptostigmata).