A review of temephos with particular reference to the West African Onchocerciasis Control Program

Perumalsamy

Pest Management Science

et al. 2015

Section: Introductionmentioning

confidence: 99%

Larvicidal activity of Magnolia denudata seed hydrodistillate constituents and related compounds and liquid formulations towards two susceptible and two wild mosquito species

Perumalsamy

Pest Management Science

et al. 2015

“…p. molestus in septic tank water. Control efÞcacy of mud loaches was compared with that of the commercial larvicide temephos 20% emulsiÞable concentrate (EC) because the larvicide is known to have very low toxicity to mammals and aquatic organisms and is less persistent in the environment (Opong-Mensa 1984). The toxicity of the temephos formulation to mud loaches was examined in AST water.…”

mentioning

confidence: 99%

Predation and Control Efficacies ofMisgurnus mizolepis(Cypriniformes: Cobitidae) TowardCulex pipiens molestus(Diptera: Culicidae) and Fish Toxicity of Temephos in Laboratory and Septic Tank Conditions

Chae

Kwon²,

Min³

et al. 2014

J Med Entomol

Culex pipiens molestus Forskal (Diptera: Culicidae) is the dominant mosquito species in septic tanks in South Korea. An assessment was made of the biological control potential of mud loaches, Misgurnus mizolepis Günther (Cypriniformes: Cobitidae), toward Cx. p. molestus larvae in laboratory and septic tanks. Results were compared with those of temephos 20% emulsifiable concentrate. In laboratory tests, all mud loaches survived on sedimentation chamber- and effluent chamber-collected water of aerobic septic tanks (ASTs), whereas all mud loaches died within 3-12 h after introduction into sedimentation chamber- and effluent chamber-collected water of anaerobic septic tanks, Gill hyperplasia and hemorrhages at the bases of pectoral fins were detected in all dead mud loaches. These appeared to have been caused by bacterial disease, rather than the physical and chemical characteristics of the septic tank water. A mud loach consumed an average range of 1,072-1,058 larvae of Cx. p. molestus in the AST water at 24 h. At the manufacturer's recommended rate (10 ml/ton) in the AST water, the temephos formulation did not cause fish mortality. In the AST experiment, predation of mosquito larvae by mud loaches at a release rate of one fish per 900 mosquito larvae resulted in complete mosquito control from the third day after treatment throughout the 18-wk survey period, compared with temephos 20% emulsifiable concentrate-treated AST water (reduction rate, 40% at 28 days after treatment). Reasonable mosquito control in aerobic septic tanks can be achieved by mosquito breeding season stocking of a rate of one mud loach per 900 mosquito larvae.

“…The results show that the larvicidal effect of temephos at 1.0% persisted for up to 50 days with at least 22 days of effective larval control. The persistence of temephos G in an aquatic environment is affected by the rate of degradation due to hydrolysis, sunlight and microbial effects, evaporation, dissolution, dispersion and adsorption to suspended particles, sediments and other surfaces (Forgash 1976; Opong‐Mensa 1984). It was important therefore to understand the environmental factors under which temephos is to be used.…”

Section: Discussionmentioning

confidence: 99%

Field efficacy and non‐target effects of temephos granules against Culex pipiens (Diptera: Culicidae) and microorganisms in septic tanks, Republic of Korea

Kang

Jeong

Lee

et al. 2011

Entomological Research

A granular formulation of 1.0% temephos (temephos G) was tested for its efficacy in mosquito larval control, residual effects and effects on non‐target microorganisms. Culex pipiens complex in septic tanks in Yangsan, Republic of Korea were used for this study. Microorganisms in the same septic tanks were used for study of non‐target organisms. After the application of temephos G at the rates of 2.0 and 5.0 mg/L to selected septic tanks, mortalities were recorded for 50 days. The effect of temephos G on non‐target organisms was studied by evaluating its effects on the bacterial populations in the treated septic tanks. It was observed that using 1.0% temephos G at a rate of 2.0 mg/L resulted in 100% mortality against Cx. pipiens larvae by the eighth day after treatment. The residual activity of temephos G was observed to continue for a time; for example 29 days after treatment, average larval mortality rates of >68.0% were observed for both concentrations. At the 50th day after treatment, the mortality rates of the Cx. pipiens larvae were observed to decrease to below 42.7% for both concentrations. Application of temephos G did not have significant effects on the bacteria populations in the septic tanks. Since temephos did not seem to have any major effects on the microorganisms, it was concluded that it is a safe and effective larvicide to use in the septic tanks at a rate of 2.0–5.0 mg/L of 1.0% temephos G.