Pesticides, mixing

The vaporous collar contains a relatively high-vapor-pressure liquid pesticide mixed throughout the collar. The pesticide is slowly released and fills the atmosphere adjacent to the animal s surface with a vapor of pesticide that kills the pest but is innocuous to the animal. 

Employees at hazardous waste sites, employees at pesticide mixing and formulating plants, and farm workers are more likely to be exposed to disulfoton than individuals in other occupations. Neurotoxl effects have been observed in occupationally exposed persons. However, no human data were located to identify susceptible subpopulations. Animal data suggest that female animals and young animals are more susceptible to disulfoton toxicosis. Based on the results from animal studies, women and children could also be more susceptible than men to toxic effects of disulfoton. 

Table I Summary of the Effect of Ambient Conditions, Aeration at 1 L/min, Peptone Nutrient at 0.1 Wt. %, Concentration, and the Presence of 5 Other Pesticides (Mix) on the Degradation of Six Pesticides and Two Decomposition Products... 

The unit was mounted on a 8 x 18 foot trailer, tightly secured, and moved some 5 miles to the pesticide mixing and loading area on the BARC research facility (Figure 2). 

The ETTA technology was demonstrated for removal of pesticides from soil in the U.S. Environmental Protection Agency (ERA) Superfund Innovative Technology Evaluation (SITE) program in September 1992 at an abandoned pesticide mixing site in western Arizona. This technology has also been used to remove VOCs and SVOCs in full-scale applications at five other sites. The technology is commercially available. 

Field observations during aerial spray applications have demonstrated that anywhere from 15-75% of the pesticide mix admitted from the aircraft reaches the forest canopy (2). In some cases under unstable conditions, "on-target" deposit was less than 2% of the total emitted material. The portion of the spray deposit that does not land "on-target" (i.e. on conifer foliage) may be transported to aquatic and other non-target habitats. Overall, the amount of adjuvants in the mixes that deposits onto... 

SAFETY PROFILE Moderately toxic by ingestion and intraperitoneal routes. An eye and skin irritant. A pesticide. Mixed with CaO and put into fused CaCb, the mixture incandesces. See also BORON COMPOUNDS. 

A poisonous bait is a pesticide mixed with an edible material that is attractive to a particular pest. The pests are killed by consuming a lethal dosage of the poison either in a single feeding or over a period of time. Baits are sometimes used to control rodents. Although you may not need to cover the whole area, the bait must be placed where it is likely to be consumed. 

Low levels of an applied herbicide-pesticide-solvent mix were drawn into the uptake air of a commercial building following the application of a pesticide mix to the lawn in front of that building. Several employees immediately reported CNS and respiratory symptoms, with one sustaining a permanent respiratory injury. The pesticide mix applied to the lawn was composed of 2,4-D (2.82), 2-(2-methyl-4-chlorophenoxy) propionic acid (MCPP 2.48), and dicamba (2.21). The mixture also contained solvent naphtha (a mixture of aliphatic solvents, Kqw = 3.5-5.0) with 14% naphthalene (2.48) and dinitroaniline (3.30). The concentrations of all pesticides and solvents were far below the TLVs both outside and inside the building. The toxic effects observed were ascribed to the mixture of lipophilic and hydrophilic pesticides. 441... 

Low levels of an applied herbicide/pesticide mix were drawn into the air conditioning makeup air of a commercial building. Workers reported neurological symptoms that included nausea, dizziness, and headache immediately after the pesticide mix was applied. Chemicals contained in the mix included... 

Sprays. Aerosol spray emulsions are of the water-in-oil type. The preferred propellant is a hydrocarbon or mixed hydrocarbon—hydrofluorocarbon. About 25 to 30% propellent, miscible with the oil, remains in the external phase of the emulsion. When this system is dispensed, the propellant vaporizes, leaving behind droplets of the w/o emulsion (Fig. 2b). A vapor tap valve, which tends to produce finely dispersed particles, is employed. Because the propellant and the product concentrate tend to separate on standing, products formulated using this system, such as pesticides and room deodorants, must be shaken before use. 

Naphthalene, anthracene, carbazole [86-74-8] phenol [108-95-2] and cresyUc acids are found in the tar. Phenol and cresyUc acids are useful as chemical and resin intermediates. The aromatic chemicals are useful in the manufacture of pharmaceuticals, dyes, fragrances, and pesticides. Various grades of pitch are made from residues of tar refining. Coal-tar pitch is used for roofing and road tar, and as a binder mixed with petroleum coke to produce anodes for the aluminum industry. 

One of the first complete, continuous simulation models was the pesticide mnoff transport model (PRT) (56). Improvements in the PRT modelled to the hydrologic simulation program—FORTRAN model (57). A number of other models have been developed (58,59). These models represent a compromise between the avadable data and the abiHty to encompass a wide range in soils, climates, and pesticides. These models have had mixed success when extended beyond the data with which they were caHbrated. No model has yet been developed that can be proven to give accurate predictions of... 

Ozonation can be enhanced by the addition of ultraviolet (uv) radiation. This combination can be effective in degrading chlorinated organic compounds and pesticides. In addition, metal ions such as iron, nickel, chromium, and titanium [7440-32-6] can act as catalysts, as can ultrasonic mixing. 

The main purpose of pesticide formulation is to manufacture a product that has optimum biological efficiency, is convenient to use, and minimizes environmental impacts. The active ingredients are mixed with solvents, adjuvants (boosters), and fillers as necessary to achieve the desired formulation. The types of formulations include wettable powders, soluble concentrates, emulsion concentrates, oil-in-water emulsions, suspension concentrates, suspoemulsions, water-dispersible granules, dry granules, and controlled release, in which the active ingredient is released into the environment from a polymeric carrier, binder, absorbent, or encapsulant at a slow and effective rate. The formulation steps may generate air emissions, liquid effluents, and solid wastes. 

ORGANIC PHOSPHORUS COMPOUND, MIXED WITH COMPRESSED GAS ORGANOCHLORINE PESTICIDES, FLAMMABLE, LIQUID, TOXIC, n.o.s.,... 

Baird is the 20-acre site of a former chemical mixing and batching company. Poor waste disposal practices resulted in the contamination of groundwater, soil, the municipal water supply, and a brook adjacent to the site. Over one hundred contaminants, including chlorinated and nonchlorinated volatile organics, heavy metals, pesticides, herbicides, and dioxins, had been identified in site soil and groundwater. Remediation activities included soil excavation and incineration, and groundwater treatment (the audit focused on the soil excavation and incineration... 

Lovell RA, McChesney DG, Price WD. 1996. Organohalogen and organophosphoms pesticides in mixed feed rations Findings from FDA s domestic surveillance during fiscal years 1989-1994. J Assoc Off Anal Chem 79 544-548. 

Applicators, mixers, loaders, and others who mix, spray, or apply pesticides to crops face potential dermal and/or inhalation exposure when handling bulk quantities of the formulated active ingredients. Although the exposure periods are short and occur only a few times annually, an estimate of this exposure can be obtained by quantifying the excreted polar urinary metabolites. Atrazine is the most studied triazine for potential human exposure purposes, and, therefore, most of the reported methods address the determination of atrazine or atrazine and its metabolites in urine. To a lesser extent, methods are also reported for the analysis of atrazine in blood plasma and serum. 

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