Dermal dosimetry

Collection of air samples during simultaneous dermal dosimetry-biological monitoring studies... 

Chapter two. Simultaneous biological monitoring and dermal dosimetry... 

Honeycutt, R.C., Day, Jr., E.W., Shurdut, B.A., and Vaccaro, J.R., Use of simultaneous biological monitoring and dermal dosimetry techniques to determine the exposure of chlorpyrifos to applicators and re-entry workers, in Worker Exposure to Agrochemicals Methods for Monitoring and Assessment, Honeycutt, R.C. and Day, E.W., Jr., Eds., Lewis Publishers, Boca Raton, FL, 2000, chap. 2. 

In the early 1980s, the whole-body dosimeter (WBD) was introduced as a superior method for passive dermal dosimetry monitoring. A standard protocol was described by the World Health Organization (1982), and Abbott et al. (1987) described some additional options. Chester (1993) reported refinements that permitted exposure estimation by passive dermal dosimetry and biological monitoring simultaneously. 

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). 

The calculation of potential total dermal exposure of mixer-loaders and re-entry workers using dosimetry data and calculation of the internal dose using biological monitoring data is complex but will be discussed briefly. 

This study was conducted to evaluate and compare ADD determined using whole-body dosimetry with results of two situational exposure studies conducted following use of a flea fogger under natural conditions. Chlorpy-rifos was selected due to its general availability as a fogger for indoor flea control. Chlorpyrifos is poorly absorbed by the dermal route and readily cleared from the body in urine (Nolan et al., 1984). Trichloropyridinol was measured in 24-hr urine specimens of the volunteers and was converted to chlorpyrifos equivalents as a measure of absorbed dose. The study provided an opportunity to determine the relationship between intensive, high-contact dosimetry studies and the amounts of chlorpyrifos absorbed by two sets of adults who re-entered fogger-treated homes. 

Krieger, R.I., Bernard, C.E., Dinoff, T.M., Fell, L., Osimitz, T. G., Ross, J.I., and Thongsinthusak, T. (2000) Biomonitoring and whole body cotton dosimetry to estimate potential human dermal exposure to semivolatile chemicals, /. Exposure Anal. Environ. Epidemiol., 10 50-57. 

Epidemiological and Human Dosimetry Studies. There were limited data that indicated that the use kerosene stoves in the home is not associated with increased respiratory illness (Azizi and Henry 1991 Tominaga and Itoh 1985), although chronic dermal exposure to kerosene has been related to dermatosis (Jee et al. 1985). These studies are of limited use, however, since neither exposure nor duration of exposure were reported. 

Humans may be exposed to 2-hexanone through contaminated air in the workplace and in the vicinity of hazardous waste sites and consumption of and dermal contact with contaminated water, especially in the vicinity of hazardous waste sites. Epidemiological studies that followed populations exposed to 2-hexanone, either in the vicinity of hazardous waste sites or in the workplace, would be useful in assessing adverse health effects in humans. In any such studies, emphasis should be placed on neurological, hematological, immunological, reproductive, and developmental effects. Similarly, human dosimetry studies of these populations would be useful in associating 2-hexanone levels with the reported effects. 

Additional data are needed to better define the exposure of humans and, in the context of animal toxicity studies, of laboratory animals. Because JP-8 is a complex mixture of chemicals that differ in volatility, solubility, metabolic rate and pathway, and rate and route of elimination from the body, dosimetry of critical components of the mixture at critical sites in the body is important to enhance the quality of risk assessment. The fact that human exposures can involve liquid fuel, aerosolized fuel, and vapor, by inhalation, dermal, and oral routes of exposure makes it difficult to accurately predict the internal dose of JP-8 and its components. 

INTRODUCTION 14 PESTICIDE CATEGORIES 15 PESTICIDE HANDLERS 15 Agricultural Pesticide Handlers 15 Tasks Performed by an Individual 16 Factors Affecting Exposure 16 Residential and Institutional Pesticide Handlers 18 Families of Pesticide Handlers 19 STUDY DESIGN CONSIDERATIONS 20 Worker Stratification 21 Routes of Exposure 21 Respiratory Exposure 21 Dermal Exposure 21 Sampling Strategy Selection 21 Statistical Analysis 22 PROTECTION OF HUMAN SUBJECTS 22 PESTICIDE EXPOSURE MONITORING METHODS 23 Passive Dosimetry 23... 

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