Insects surface treatments

Currently there are few insecticides registered as surface treatments to control stored-product insects. For years the organophosphate insecticide malathion was used as a surface treatment for structural facilities, but stored-product insects throughout the world have developed extensive resistance to malathion (Subramanyam and Hagstrum, 1996). Most of the resistance reports were generated from studies with bulk grains, but in the United States, resistance has been documented for field populations of the red flour beetle, T. castaneum (Herbst), and the confused flour beetle, T. confusum (DuVal), collected from flour mills (Arthur and Zettler, 1991, 1992 Zettler, 1991). Populations of the Indianmeal moth, the almond moth, and the red flour beetle collected from bulk peanuts and empty warehouses were also highly resistant to malathion (Arthur et al., 1988 Halliday et al., 1988). 

Alkylphenol ethoxylates are chemically stable and highly versatile surfactants that find application in a large variety of industrial products including acid and alkaline metal cleaning formulations, hospital cleaners, herbicides (qv) and insecticides, oil-well drilling fluids, synthetic latices, and many others (see Disinfectants and antiseptics Elastomers, synthetic Insect control technology Metal surface treatments Pesticides Petroleum, drilling fluids). 

Some companies, often inspired by nature s incredible powers as seen in some plants and insects, are interested in designing surface treatment methods that can result in self-cleaning surfaces or self-ironing clothes surfaces that do not need detergents, clothes that do not need ironing ... 

For the remedial treatment of fungal decay and insect attack on timber in buildings, clear solvent-type preservatives applied by spraying all available surfaces are generally used, supplemented with wood preservative pastes to obtain deep penetration. Water-based emulsions are also used for woodworm control. There has been a general move towards the use of those... 

Pyrethroids are a class of synthetic chemicals that are similar in structure to natural pyrethrins. They have been used in field crops and urban pest management for nearly 30 years, and within the last 5 to 10 years new products have been registered for specific use against stored-product insects. Resmethrin is labeled for use as an aerosol in food plants, mills, and warehouse facilities, but could have potential side effects such as discoloration of surfaces and odor contamination and may be more appropriate for use in empty facilities. Labels generally state to cover any food prior to application. The pyrethroids esfenvalerate (Conquer) and prallethrin (Etoc) are also labeled for use in some situations as an aerosol space treatment in... 

Aquatic Invertebrates. The initial impact of insecticides on most benthic invertebrates in streams is the inability to maintain their position on the streambed resulting in increased numbers being carried downstream in what is termed drift. Invertebrate drift in treated streams is easily sampled by holding a net in the current. Post-spray catches can be compared to both pre-spray diurnal patterns and catches at an untreated upstream station or in an untreated control stream. This method also can be used to document knockdown of streamside foliage-dwelling or arboreal insects if the net is set so as to sample the stream s surface. Impacts on stream invertebrates can also be determined by caging studies and by pre- and post-spray bottom fauna population assessments which either sample the numbers within a given area of natural streambed (e.g., Surber sampler) or on artificial substrates intentionally set in the stream before treatment to be colonized by resident populations. 

Pesticides may be periodically inttoduced into indoor air by direct application (e.g. insect sprays and bombs, disinfectant sprays and room deodorizers). In addition, there are often sources that continually emit vapors into the living space (e.g. continuous evaporation of residues from crack and crevice treatments and emissions from pest-control strips or other devices). Whether used inside the home or office, or outside on the lawn or garden, pesticides accumulate on indoor surfaces, especially in carpet dust, and also in upholstery and in or on children s toys (Lewis et al 1994b, 1999 Simcox et al., 1995 Nishioka et al 1996, 1999 Gurunathan et al., 1998). 

Fenthion is a broad spectrum insecticide. When applied as a surface spray, it controls adult mosquitoes and other insect pests and spiders in agricultural, horticultural, and home garden use. Recent reports indicate that resistance to fenthion has developed in some species of mosquitoes. Fenthion is used in dermal application for treatment of swine and cattle for control of lice, flies, and ticks, and in flea and tick treatments for pets. It is also used in aqueous applications to kill dragonfly larvae in ornamental fish production ponds. Fenthion is an effective avicide, and has been marketed to control birds considered to be pests. 

Space spray treatments have their limitations in that they will only control insects present at time of treatment and the insecticide will not penetrate deeply into cracks and crevices where many insects live. Consequently, frequent treat -ments are necessary for reliable control. Also, although insecticide will be deposited from space sprays onto horizontal surfaces and have some immediate effect, this will not he adequate to function as a residual insecticide. As a general hygiene precaution all food materials or surfaces upon which food will be handled are liable to deposition and must be covered during spraying. 

In contrast to the residual spray treatment, the dosage of pesticide applied as a fog is low when flying insects are to be killed. There is generally no intention of providing a residual deposit as the pesticide is deposited virtually only on the top of leaves and other relatively horizontal surfaces. A sequential series of treatments is used if reinfestation occurs. However, the technique has been... 

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