Aerial applications

Mental disturbances have been reported after organophosphate exposure. Neuropsychiatric symptoms occurred in two aerial applicators, one of whom used methyl parathion as well as other insecticides. One of these pilots had high levels of exposure to a mixture containing methyl parathion, toxaphene, and Dipterex when his clothing became saturated when the tank of his aircraft accidentally overflowed. Several months after the accident, the subject complained of anxiety, dizziness, emotional lability, and frequent and severe disagreements with family members and associates. Similar observations had been... 

As a result of its use as an insecticide on cotton, fruit trees, vegetables, and other crops, methyl parathion is released directly to the atmosphere during application. It is applied primarily by spraying from aircraft or ground equipment (NPIRS 1986). Aerial application of methyl parathion to agricultural fields releases the insecticide to the air. 

Methyl parathion can be released to surface waters by storm runoff from sprayed fields atmospheric deposition following aerial application (wet deposition from rain and fog water) waste water releases from formulation, manufacturing, or processing facilities and spills. 

Draper WM, Street JC. 1981. Drift from a commercial, aerial application of methyl and ethyl parathion An estimation of potential human exposure. Bull Environ Contam Toxicol 26 530-536. 

In field trials following multiple aerial applications of endosulfan for tsetse fly control in Africa over a 3-month period, residues of the compound in fish tissues decreased to low concentrations within 3 months after spraying. The fish tissue residues were still detectable after 12 months. Residue concentrations in fish-eating birds and crocodiles were similar to fish tissue residue levels endosulfan did not biomagnify in the food chain (HSDB 1999). 

At Eglin AFB, Florida, the U.S. Air Force initiated an experiment in 1962 to test aerial application equipment for deposition of defoliants... 

Aerial application equipment should be calibrated as follows ... 

The aerial application of DDT insecticides to 413,000 acres protected 1,500,000,000 board feet of lumber at an estimated stumpage value of 4,600,000. 

Draper, W.M., R.D. Gibson, and J.C. Street. 1981. Drift from and transport subsequent to a commercial aerial application of carbofuran an estimation of potential human exposure. Bull. Environ. Contam. Toxicol. 26 537-543. 

Individual applications of 0.014-0.019 kg/ha, emulsifiable concentrate, oil diluent, 3 applications at 5-week intervals 0.02 kg/ha, granularformulation, single application 0.025 kg/ha, single application 0.028 kg/ha (0.025 Ibs/acre), single aerial application, mosquito larvicide granules Individual applications of 0.028 kg/ha, 4 applications at 2-week intervals... 

Reisen, W.K., G. Yoshimura, W.C. Reeves, M.M. Milby, andR.P. Meyer. 1984. The impact of aerial applications of ultra-low volume adulticides on Culex tarsalis populations (Diptera Culicidae) in Kern County, California, USA, 1982. Jour. Med. Entomol. 21 573-585. 

Cunningham, P.A. and L.E. Myers. 1986. Dynamics of diflubenzuron (dimilin) concentrations in water and sediment of a supratidal saltmarsh site following repetitive aerial applications for mosquito control. Environ. Pollut. 41A 63-88. 

Schaefer, C.H. and E.F. Dupras, Jr. 1977. Residues of diflubenzuron [l-(4-chlorophenyl)-3-(2,6-difluoroben-zoyl) urea] in pasture soil, vegetation, and water following aerial applications. Jour. Agricul. Food Chem. 25 1026-1030. 

Sundaram, K.M.S., S.B. Holmes, D.P. Kreutzweiser, A. Sundaram, and P.D. Kingsbury. 1991. Environmental persistence and impact of diflubenzuron in a forest aquatic environment following aerial application. Arch. Environ. Contam. Toxicol. 20 313-324. 

Adverse effects of fenvalerate on survival of terrestrial arthropods were observed at 0.002 to 0.015 pg whole-body topical application, O.llkg/ha aerial application, 5.4 mg/kg in the soil, 50 mg/kg in the diet, and 1.4 g/ant mound (Table 20.4). Synthetic pyrethroids are more effective in biological systems at low temperatures. The relative sensitivity of insects when compared with mammals is attributed in part to this negative temperature coefficient. Thus, warm-blooded animals are less affected than insects and other poikilotherms (Klaassen etal. 1986). Fenvalerate, for example, showed a negative correlation between temperature and toxicity to crickets (Acheta pennsylvanicus), being up to 1.9 times more toxic at 15°C than at 32°C (Harris etal. 1981). A similar case is made for honey bees (Apis mellifera) (Mayer et al. 1987) and for many species of aquatic invertebrates and fish (Mayer 1987). 

Phillips, S.A., Jr. D.M. Clabom, and O.F. Francke. 1984. Comparison of aerial application and single-mound drenches of fenvalerate against the red imported fire ant, Solenopsis invicta Buren, in Texas. Southwestern Entomol. 9 164-168. 

Kendall, R.J., R. Noblet, J.D. Hair, and H.B. Jackson. 1977. Mirex residues in bobwhite quail after aerial application of bait for fire ant control, South Carolina — 1975-76. Pestic. Monitor. Jour. 11 64-68. 

Summerlin, J.W., A.C.F. Hung, and S.B. Vinson. 1977. Residues in nontarget ants, species simplification and recovery of populations following aerial applications of mirex. Environ, Entomol. 6 193-197. 

The timing of application of 1080 baits is critical. In one mishap, baits were dropped aerially while many ground squirrels — the targeted species — were still in hibernation underground for the winter and had not emerged (Collins 1965). Aerial application of 1080 baits in a ground squirrel... 

Collins, B.D. 1964. An Evaluation of an Experimental Aerial Application of Toxic Baits for Squirrel Control — Kern County. California Dept. Fish Game, Pesticides Investigations. Mimeographed. 10 pp. 

Collins, B.D. 1965. Fish and Game s view on aerial application of 1080 baits for squirrel control. County Agricultural Commissioners Meeting, Bijou, California, 18 May 1965. Mimeographed. 4 pp. 

Spurr, E.B. 1994. Impacts on non-target invertebrate populations of aerial application of sodium monofluoroacetate (1080) for brushtail possum control. Pages 116-123 in A.A. Seawright and C.T. Eason (eds.). Proceedings of the Science Workshop on 1080. Roy. Soc. N.Z., Misc. Ser. 28. 

One of the special rotary atomizers worth mentioning is the windmill type atomizer. In this atomizer, radial cuts are made at the periphery of a disk and the tips of segments are twisted, so that the disk is actually converted into a windmill that can rotate rapidly when exposed to an air flow at aircraft flight speed. The windmill type atomizer has been demonstrated 1171 to be an ideal rotary atomizer for generating a narrow spectrum of droplet sizes in the range most suitable for aerial applications of pesticides at relatively high liquid flow rates. 

Other than aerial application over swamps for mosquito abatement, disulfoton is not known to be used over water. Potential sources of release into surface water include discharge of waste water from disulfoton manufacturing, formulation, and packaging facilities (HSDB 1994). Leaching and runoff from treated fields, pesticide disposal pits, or hazardous waste sites may contaminate both groundwater and surface water with disulfoton. Entry into water can also occur from accidental spills. Small amounts of volatilized disulfoton may be removed from the atmosphere as a result of wet deposition and may enter surface water (Racke 1992). 

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