Pesticide water-soluble

Sulfur and its compounds are among the oldest and most widely used pesticides. Elemental sulfur is especially effective as a dust for the control of mites attacking citms, cotton, and field crops and as a protectant against chiggers, Trombicula spp., attacking humans. Sulfur also is a valuable fungicidal diluent for other dust insecticides and is used in wettable form as a spray mixture. Time sulfur has been a standard dormant spray for the control of the San Jose Quadraspidiotuspemiciosus and for other scales and various plant diseases. Time sulfur is a water-soluble mixture of calcium pentasulfide,... 

Dihexyl sulfosuccinate is used to improve the wetting and spreading characteristics of water-soluble pesticide sprays. In liquid fertilizers, insecticides, and fungicides, dioctyl sulfosuccinate will increase their penetrating ability. 

Exposure assessments are commonly done using computer modeling (e.g., Pesticide Handlers Exposure Database [PHED]). Computer modeling was not used for cyromazine 75 WG because of the limited information in the database on wettable powders packed in water-soluble bags at the time the study was planned. 

Due to the low volatility of cyromazine and the use of water-soluble bags for packaging the Trigard formulation, the main routes of exposure were expected to be from direct contact with the product or spray mixture on contaminated surfaces. Previous experience with pesticides worker exposure studies indicated that exposure from vapors or spray mist would be a minor factor. This can easily be confirmed by the PHED or similar published sources however, the extent of exposure from inhaling the product as dust is less well known. This route of exposure was also assumed to be minor, particularly with the use of water-soluble bag packaging. Given the low mammalian toxicity of cyromazine, the operators did not wear respiratory protection. 

At the fundamental level of equilibrium modeling the advantages are many. The model can combine a number of compartments through simple relationship to describe a realistic environment within which chemicals can be ranked and compared. Primary compartments that chemicals will tend to migrate toward or accumulate in can be identified. The arrangement of compartments and their volumes can be selected to address specific environmental scenarios. Data requirements are minimal, if the water solubility and vapor pressure of a chemical are known, other properties can be estimated, and a reasonable estimate of partitioning characteristics can be made. This is an invaluable tool in the early evaluation of chemical, whether the model be applied to projected environmental hazard or evaluation of the behavior of a chemical in an environmental application, as with pesticides. Finally, the approach is mathematically very simple and can be handled on simple computing devices. 

Ren H, Endo H and Hayashi T (2001a), Antioxidative and antimutagenic activities and polyphenol content of pesticide-free and organically cultivated green vegetables using water-soluble chitosan as a soil modifier and leaf surface spray , JSci FoodAgric, 81, 1426-1432. 

Pentachlorophenol is readily soluble in most organic solvents, oils, and highly aromatic and olefinic petroleum hydrocarbons — a property that makes it compatible for inclusion in many pesticide formulations (Table 23.1 Figure 23.1). Purified PCP, however, is practically insoluble in water therefore, the readily water-soluble sodium pentachlorophen-ate salt is substituted in many industrial applications (Table 23.1) (Bevenue and Beckman 1967 USPHS 1994). 

A plot of time interval (in days) since application of the pesticide to soil versus percentage of original pesticide addition remaining in soil after various time intervals (31, 66 and 93 days) shows that, for example, after 30 days, in the case of the less water soluble Fluometruron (solubility in water 200mg L ) some 30-40% remains in the soil, while in the case of the more water soluble Aldoxycarb (solubility in water 9000mg L-1) some 13% remains in the soil. After 90 days exposure the corresponding figures are 18% and 1%. 

Disulfoton is a systemic insecticide/acaricide that belongs to the organophosphate class of pesticides. Pure disulfoton is a colorless oil with low volatility and water solubility, but is readily soluble in most organic solvents (Worthing 1987). Information regarding the physical and chemical properties of disulfoton is located in Table 3-2. 

Disulfoton is also transported through soils or from soil to surface water (streams or rivers) via runoff. Pesticides with water solubilities >10 mg/L move mainly in solution phase in runoff water (Racke 1992). Disulfoton, with a water solubility of 25 mg/L (Sanborn et al. 1977), is expected to be found mainly in runoff water. In a runoff event from agricultural soil in Nebraska, low levels of disulfoton were detected both in the dissolved state and in eroding soil particles in the sorbed state (Spalding and Snow 1989). 

With the exception of picloram and phenols (Fig. 10, Table 3), acidic pesticides are considered nonvolatile from aqueous and soil systems [153]. Some ester formulations of these compounds also behave as herbicides. They do not ionize in solution and are less water-soluble than the acid or salt forms. They are eventually hydrolyzed to acid anions in aqueous and soil systems, but in the ester form are non-ionic and relatively volatile. 

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