Applicators potential exposure

Endosulfan is a popular pesticide with greenhouse chrysanthemum producers. Surveys of usage patterns and potential exposure were conducted in Ontario (Archibald et al. 1994b). Collection and analysis of a-and P-endosulfan and endosulfan sulfate in greenhouse air have been described (Vidal et al. 1997). Results indicate that 7.5% of the initial concentration of endosulfan remained in the greenhouse atmosphere 24 hours after application. 

Before the EPA proceeds on a regulatory action, registrants whose products exceed the 10 risk level from nitroso contamination, will be given the opport mity to lower potential exposure to applicators and other users of their pesticides. Reduction of exposure and, thus, reduction of risk can be accomplished by modification of the manufacturing process (see below), improved packaging technology, modification of application technique (e.g. closed systems), or deletion of high-exposure uses. 

Application of the test substance to the target crop prior to harvest represents a worst-case scenario for potential exposure to workers for the crop category. 

PCP is commonly used as a wood preservative having both antifungal and insecticide properties. It has also been used in a range of areas for antifungal, antibacterial, general herbicide, and slime prevention in both industrial and consumer applications. Chronic exposure to PCP has effects on the liver, kidneys, and immune system. PCP also has the potential to cause reproductive problems and has been listed as a probable carcinogen. 

Honeycutt, R.C. and DeGeare, M.A., Evaluation of the Potential Exposure to Chlorpyrifos During Mixing and Loading, Spray Application, Clean-Up Procedures During the Treatment of Citrus Groves with Lorsban 4E Insecticide, unpublished report, HERAC, Inc., January 18, 1994. 

The major area (approximately 60%) of the potential exposure of the applicators was located on the legs, whereas 50% of the potential exposure of the harvesters was equally distributed to the hands and torso. Total body exposure differed significantly between workers. 

The variances of potential dermal exposure are presented in Table 1. Very large "within-worker" variances of potential exposure of the hands resulted in insignificant differences between workers. For harvesters, a similar result was obtained for potential exposure of the body parts. For both applicators and harvesters, significant "between-worker" differences of total potential exposure were observed. 

Figure 1 shows the distribution of the potential exposure. The major area of potential exposure of the applicators (approximately 60%) was located on the legs, particularly the lower legs. Exposure of the legs of the harvesters was approximately half that of the applicators. For harvesters, approximately 25% of the exposure was located on the torso and another 25% on the hands. 

For applicators, hand exposure was approximately 15% of the total potential dermal exposure. 

Nigg and Stamper (1983) conducted potential exposure and actual exposure measurements during three weekdays over three consecutive weeks for applicators and mixer-loaders, one week using normal work clothes, the second week disposable coveralls in addition to their work clothes, and the third week disposable coveralls and NIOSH-approved respirators. In conjunction, urinary excretion of a metabolite of the active ingredient was... 

The design of a study by Davies et al. (1982) for mixers and applicators was similar to that of Nigg and Stamper (1983). "Between-days" variances of exposure were not given. Mean urinary metabolite concentrations were used to show reduction of internal exposure by protective clothing. The design of the study by van Rooij et al. (1993) was similar to our study (i.e., "within-worker" comparisons of internal exposure). Because no potential dermal exposure was assessed in this study, "within-worker" variances of potential exposure are not known. 

Davis JE, Stevens ER, Staiff DC, et al. 1983. Potential exposure to diazinon during yard applications. Environmental Monitoring and Assessment 3 23-28. 

The survey covered a period of 3 years of potential exposure, but exposure levels were not reported. No adverse dermal effects were observed on the arms or legs of subjects after a 6-day application of polymer fibers containing commercial octabromobiphenyl mixture under an occlusive covering no additional information was reported (Waritz et al. 1977). 

While information on uses is available (Mannsville Chemical Products Corporation 1999), specific information on uses in certain potentially high exposure applications is either changing or lacking. Specifically, information on the use of DEHP in food contact applications such as coatings used in cans, bottle caps, and films would allow a better estimation of potential exposures from food. Currently, the only information available is that these applications are allowed by FDA rules, but it is unclear if DEHP is used. 

For each potential exposure source, various exposure scenarios and populations are examined. For the HRA for TOCDF, for instance, these included subsistence ranchers, residents, workers, and people engaged in various nearby recreational activities. Potential emissions release into, and transport through, the environment are modeled considering all applicable media, e.g., air, water, and solids, to provide exposure estimates.17... 

The application of the same basic and formal principle to all biological products, including inactivated vaccines appears exaggerated. However, Commission Directive 92/18/EEC describes the same principle of a basic assessment ("shall always be carried out"), followed by ecotoxicity tests in the case of "potential exposure of the environment" also under Title II, which is specific for immunological veterinary medicinal products. 

The goal of this text is to provide a critical assessment of the current state of knowledge of exposure assessment of pesticides and to provide recommendations to advance our ability to fully characterize and accurately assess their potential exposure and risks. While the focus is on pesticides, many of the principles are also applicable to other classes of chemicals and it is hoped that this book will help encourage cross-fertilization among various disciplines. Significant progress... 

Fenske, R.A., K.G. Black, K.P. Elkner, C.L. Lee, M.M. Methner and R. Soto (1990). Potential exposure and health risks of infants following indoor residential pesticide applications. Am. J. Public Health, 80, 689-693. 

Waldron, A.C. (1985). The potential for applicator-worker exposure to pesticides in greenhouse operations, in Dermal Exposure Related to Pesticide Use, R.C. Honeycutt, G. Zweig and N.N. Ragsdale (Eds), ACS Symposium Series 273, American Chemical Society, Washington, DC, USA, pp. 311-319. 

Residential risk assessment to pesticides typically involves more than one sonrce and mnitiple pathways and rontes, e.g. a given active ingredient may be nsed for multiple indoor apphcations, and in some cases, for outdoor applications. In some cases, the applications may overlap with respect to timing (calendar days). The potential co-occurrence of applications and potential exposures requires temporal product use information. Such information is rarely available. 

This study provides a means for conservatively estimating potential post-application dermal exposures to treated surfaces following the use of indoor total release foggers by using a high-contact, but reproducible activity. The procedure for estimating potential dermal exposure is based on the use of transfer factors (TFs) derived from the human volunteer dermal dosimetry and treated carpet transferable-residue measurements based on an indoor roller method (Ross et al, 1990, 1991). 

For applications, a distinction is made between downward and upward spraying. Nominal values for potential exposure are taken as the upper limit of the class containing the 75th percentile of the available database. 

Formulation type Application equipment Route of exposure Potential exposure (mg/kg a.s.) ... 

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