Low-volume formulations

ULV has been commonly used as an abbreviation tor ultra-low-volume formulations. The standard GCPF (formerly GIFAP) 2-character code is UL (8). 

Formulations applied as sprays include wettable powders, suspension concentrates, emulsifiable concentrates, encapsulated formulations and ultra-low-volume formulations. Wettable powders consist of finely divided pesticide particles combined with a finely ground dry carrier (e.g., synthetic silica, mineral clay) and surfactants (6). When the powder is mixed with water, a stable homogeneous particle suspension is formed. Suspension concentrates are particulate insecticides premixed with a liquid. When sprayed onto porous media, the water in particle suspensions penetrates the medium leaving the insecticide at the surface. On nonporous surfaces, the water evaporates leaving a deposit. 

A third criterion for the proper formulation of house paints is volume soHds level. Paint with low volume soHds are characterized by poor adhesion and poor exterior durabiUty. A low volume soHds paint film does not have the tensile strength properties necessary for good adhesion found in a higher volume soHds paint (10). Also, any slight dismption or imperfection in the dried paint film or in the appHcation of a low volume soHds paint can result in poor durabiHty properties. 

Jojoba. Jojoba oil [61789-91-1] is obtained from the seeds of the jojoba plant grown in semiarid regions of Costa Rica, Israel, Mexico, and the United States. The oil is made up of ca 80 wt % of esters of eicos-ll-enoic and docos-13-enoic acids, and eicos-ll- -l-ol, and docos-13- -l-ol, ca 17 wt % of other hquid esters, with the balance being free alcohols, free acids, and steroids. Jojoba oil is used primarily in the formulation of cosmetics. Hydrogenated jojoba oil is a wax used in candles and other low volume specialty apphcations. 

In formulating adhesives, it is desirable to use materials with low cost. For specialty adhesives such as the acrylics, it is preferred to use commodity chemicals with a range of other uses. Minor components such as reactive rubbers, functional monomers and some additives are specially synthesized for acrylics, but these are expensive due to low volume. 

Similarly, low volume chemicals are classified according to whether they are sold primarily on the basis of specification or performance. Specialties are generally formulations that are sold on the basis of their performance and their prices reflect their value rather than cost of production. Producers of specialty chemicals often provide extensive technical service to their customers. Examples of specialty chemicals include pharmaceuticals, pesticides, flavours and fragrances, specialty polymers, etc. Fine chemicals, on the other hand, are produced to customer specifications and are often intermediates or active ingredients for specialty chemicals, e.g. pharmaceutical and agrochemical intermediates and bulk actives. 

Wheeler, H.G., Smith, F.F., Yeomans, A.H., and Fields, E. Persistence of low-volume and standard formulations of malathion on lima bean foliage, J. Econ. EntomoL, 60 400-402, 1967. 

USP Dissolution Apparatus 1 (basket) and 2 (paddle) are commonly used for immediate-release formulations. USP Apparatus 3 (reciprocating cylinders) is the system of choice for testing extended-release products or a dosage form that requires release profiling at multiple pH levels and time points. Low-dose products may require the use of flow-through analysis or other low-volume test techniques (noncompendial 100- or 200-mL dissolution vessels). Once the apparatus is selected and has been shown to be suitable during method development, no further evaluation of another apparatus is required during validation. 

Typically, in this Lrstn vivo pharmacokinetic screening, both intravenous and oral formulations are administered to a rodent species, predominantly rats. If it is possible, the same formulation should be used for both intravenous and oral arms. Although in the discovery phase it is preferable to use low volume, high-concentration cosolvent formulations to increase solubility and hence the amount of drug dosed, it does have increased risks of hemolysis and tissue irritation when administered intravenously. Therefore, cautions need to be taken not to exceed the toxicity levels for the cosolvent. 

The product used was a low-volatile 2,1, 5-T propylene glycol butyl ether ester formulation containing 0.0U ppm 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). It was applied as an emulsion in water at a rate of 1.6 pounds of 2,1, 5-T acid equivalent per acre (lb/A) in the backpack study, and 2 lb/A in the other studies. These were low-volume applications at 10 gal/A in the ground studies and 5 gal/A by air. Thus, the workers in the aerial studies were exposed to about 5 2,1, 5-T spray solutions compared to the 2 or 3 used in the earlier studies by Dow and EPA described above (3, 7). 

While each of these milestones brought forth a renewed interest in chemical weed control and led to more research in the field, the use of chemicals for selective weed control in crops was very limited and not very successful until the discovery and development of 2,4-D, MCPA, and other phenoxyacetic acid herbicides in the 1940s. These compounds were the first truly selective herbicides that could reliably kill broadleaf weeds in cereal crops, including com, and they quickly developed widespread popularity and use after World War II. With this major milestone, new application technology emerged, including the low-volume sprayer, and new herbicide formulations were developed. 

Data from Tables I-V show that deposits in the open from low-volume aerial sprays range from 8 percent to 82 percent and beneath trees from 3 percent to 39 percent. The percentages vary due to drop size of the spray, meteorology, properties of the tank mix, and release height. Improved formulations, uses of low volatile tank mixes, attention to atmospheric conditions which support deposition, and improvement in sampling methods should increase accountancy. 

Uses Pure endosulfan is a colorless crystal. The USEPA has grouped it under RUP. The technical-grade endosulfan is made up of a mixture of two molecular forms (isomers) of endosulfan, the alpha- and beta-isomers and appears brown to yellow in color. The formulations of endosulfan include emulsifiable concentrate, wettable powder, ultra-low volume (ULV) liquid, and smoke tablets.14... 

Uses Pure azinphos-methyl is a white crystalline solid technical azinphos-methyl is a brown waxy solid. Based on toxicity, the USEPA has grouped it under RUP. Azinphos-methyl is a highly persistent, broad-spectrum insecticide. It is used for the control of mites and ticks, and it is poisonous to snails and slugs. It also is used in the control of many insect pests on a wide variety of fruit, vegetable, nut, and held crops, as well as on ornamentals, tobacco, and forest and shade trees. Outside the United States, azinphos-methyl is used in lowland rice production. Azinphos-methyl is available in emulsihable liquid, liquid flowable, ultra-low volume (ULV) liquid, and wettable powder formulations.28,29... 

Uses The formulations of fenitrothion include dusts, emulsifiable concentrate, flowable, fogging concentrate, granules, ultra-low volume, oil-based liquid spray, and wettable powder formulations (Novathion 500-E, EC as a 95% concentrate,... 

Uses Pure fenthion is a colorless liquid. Technical fenthion is a yellow or brown oily liquid with a weak garlic odor. It is grouped by the USEPA under RUP and requires handling by qualified, certified, and trained workers. Fenthion is used for the control of sucking and biting pests (e.g., fruitflies, stem borers, mosquitoes, cereal bugs). In mosquitoes, it is toxic to both the adult and the immature forms (larvae). The formulations of fenthion include dust, emulsifiable concentrate, granular, liquid concentrate, spray concentrate, ultra-low volume, and wettable powder.28... 

Deltamethrin is a crystalline powder, white or slightly beige in color. The formulations include emulsifiable concentrates, wettable powders, ultra-low volume and flowable formulations, and granules. There are no known incompatibilities with other common insecticides and fungicides. It is used as a contact poison to control apple and pear suckers, plum fruit moths, caterpillars on brassicas, pea moths, aphids (apples, plums, hops), winter moths (apples and plums), and codling and tortrix moths (apples). It also is used in control of aphids, mealybugs, scale insects, and whiteflies on glasshouse cucumbers, tomatoes, peppers, potted plants, and ornamentals.9-11... 

Disadvantages Standard vessel volumes may not be suitable for low-dose formulations due to analyte dilution factors Chemical and mechanical calibration procedures do not exist Equipment may not be available in many laboratories... 

Organophosphorus compounds such as malathion and fenitrothion were introduced in 1975 and remained in use in 1997 in seven countries. WP formulations are the most common for indoor residual applications. However, in some countries, notably Brazil and Mexico, malathion and fenitrothion ultra-low-volume (UL) sprays and fogging have also been used as space sprays. In Brazil, malaria has been restricted to the Amazonian region, where precarious housing... 

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