Characterizing residue transfer efficiencies using a fluorescent imaging technique
TLDR
Results of this study showed that surface loading and skin condition (significant at alpha=0.05) are among the important parameters for characterizing residue transfers of riboflavin.Abstract:
To reduce the uncertainty associated with current estimates of children's exposure to pesticides by dermal contact and indirect ingestion, residue transfer data are required. Prior to conducting exhaustive studies, a screening study to identify the important parameters for characterizing these transfers was designed. A fluorescence imaging system was developed (Ivancic et al., in press) to facilitate collection of surface residue transfer data for repeated contacts. Next, parameters that affect residue transfer from surface-to-skin, skin-to-other objects, and skin-to-mouth were evaluated using the imaging system and the fluorescent tracer riboflavin as a surrogate for pesticide residues. Riboflavin was applied as a residue to surfaces of interest. Controlled transfer experiments were conducted by varying contact parameters with each trial. The mass of a tracer transferred was measured and the contact surface area estimated using video imaging techniques. Parameters evaluated included: surface type, surface loading, contact motion, pressure, duration, and skin condition. Transfers both onto, and off of, the hand were measured. To efficiently identify parameter changes resulting in significant effects, the Youden ruggedness test was used to select the combination of parameters varied in each contact trial. In this way, more than one parameter could be varied at a time and the number of trials required was minimized. Results of this study showed that surface loading and skin condition (significant at alpha=0.05) are among the important parameters for characterizing residue transfers of riboflavin. Duration of contact within the time range investigated does not have a significant effect on transfer of this tracer. Results of this study demonstrate the potential for collecting dermal transfer data using the Ivancic et al. fluorescence imaging system and provide preliminary data to reduce uncertainty associated with estimating dermal exposures resulting from contact with residue-contaminated surfaces. These data will also aid in determining what additional residue transfer data should be collected and what type of microactivity data are needed to estimate dermal and indirect ingestion exposure to residues on household surfaces.read more
Citations
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Journal ArticleDOI
Pesticides and their metabolites in the homes and urine of farmworker children living in the Salinas Valley, CA.
Asa Bradman,Donald A. Whitaker,Lesliam Quirós,Rosemary Castorina,Birgit Claus Henn,Marcia Nishioka,Jeffrey N. Morgan,Dana B. Barr,Martha E. Harnly,Judith A. Brisbin,Linda Sheldon,Thomas E. McKone,Thomas E. McKone,Brenda Eskenazi +13 more
TL;DR: Pesticides were detected more frequently in house dust, surface wipes, and clothing than other media, with chlorpyrifos, diazinon, chlorthal-dimethyl, and cis- and trans-permethrin detected in 90% to 100% of samples.
Journal ArticleDOI
Clothing-Mediated Exposures to Chemicals and Particles.
TL;DR: The state of knowledge regarding how clothing, during wear, influences exposure to molecular chemicals, abiotic particles, and biotic particles, including microbes and allergens is reviewed and critically assessed.
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Revisiting Dust and Soil Ingestion Rates Based on Hand-to-Mouth Transfer
Ross Wilson,Heather Jones-Otazo,Sanya Petrovic,Ian Mitchell,Yvette Bonvalot,David Williams,G. Mark Richardson +6 more
TL;DR: In this article, a more direct and mechanistic method was developed to estimate soil and dust ingestion rates using measures of particle loading to indoor surfaces; fraction transferred to the hands; hand surface area; fraction of hand surface areas that may be mouthed or contact food; frequency of hand-to-mouth events, amount dissolved by saliva; and exposure time.
Journal ArticleDOI
Modeled estimates of soil and dust ingestion rates for children.
TL;DR: This new modeling approach, which predicts soil and dust ingestion by pathway, source type, population group, geographic location, and other factors, offers a better characterization of exposures relevant to health risk assessments as compared to using a single value.
Journal ArticleDOI
Hand- and Object-Mouthing of Rural Bangladeshi Children 3–18 Months Old
TL;DR: In this article, the authors conducted a five-hour structured observation of the mouthing behaviors of 148 rural Bangladeshi children aged 3-18 months and found that at all ages both hand and object-mouthing frequencies were higher than those of U.S. children.
References
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Journal ArticleDOI
Children's exposure assessment: a review of factors influencing Children's exposure, and the data available to characterize and assess that exposure.
E A Cohen Hubal,Linda Sheldon,Janet Burke,Thomas McCurdy,M R Berry,Marc L. Rigas,Valerie Zartarian,N C Freeman +7 more
TL;DR: Children's activity pattern data requirements are demonstrated in the context of the algorithms used to estimate exposure by inhalation, dermal contact, and ingestion in order to reduce uncertainty in the assumptions and exposure estimates.
Journal ArticleDOI
Measurement of toxic and related air pollutants
TL;DR: A joint conference for the fifth straight year cosponsored by the Air & Waste Management Association's EM-3, EM-4 and ITF-2 technical committees, and the Atmospheric Research and Exposure Assessment Laboratory (AREAL) of the US Environmental Protection Agency, was held in Raleigh, North Carolina, May 1-4, 1990.
Journal ArticleDOI
Transfer of Contaminants from Surface to Hands: Experimental Assessment of Linearity of the Exposure Process, Adherence to the Skin, and Area Exposed During Fixed Pressure and Repeated Contact with Surfaces Contaminated with a Powder
TL;DR: Examination of the effect of one single-hand press contact and repeated contacts with a contaminated glass plate on both skin area exposed and loading of the skin for three volunteers shows overestimation of dermal exposure due to a single hand-surface contact in workplaces may occur.
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Experimental methodologies and preliminary transfer factor data for estimation of dermal exposures to particles.
TL;DR: Methods that utilized a common fluorescein-tagged Arizona Test Dust as a possible surrogate for housedust and a uniform surface dust deposition chamber to permit estimation of particle mass transfer for selected dust size fractions were developed.