Development and evaluation of a quantitative video-fluorescence imaging system and fluorescent tracer for measuring transfer of pesticide residues from surfaces to hands with repeated contacts.
A video imaging system and the associated quantification methods have been developed for measurement of the transfer of a fluorescent tracer from surfaces to hands. The highly fluorescent compound riboflavin (vitamin B2), which is also water soluble and non-toxic, was chosen as the tracer compound to simulate the transfer from surfaces to hands of pesticide residues deposited on carpeted and laminate surfaces of a residence. The system was designed around the unique properties of riboflavin. Excitation energy was centered near 440 nm (in the blue region of the visible spectrum); emitted energy was measured at 600 nm (in the red/orange region), well beyond the significant fluorescence peak maximum of natural skin. A video camera system with an image intensifier was interfaced to an image processing analysis software system. Quantification utilized chemometric techniques to account for the non-linearity of pixel detectivity and non-linear excitation strength. Method quantification and detection limits were approximately 0.1 and 0.02 micro g/cm(2), respectively. The relative error was approximately 100% at the quantification limit, but <20% at higher levels. Transfer of riboflavin to hands, resulting in dermal loadings in the range 0.1-2.0 micro g/cm(2), were measured with this system from surfaces whose loadings approximated the pesticide levels that occur in homes after broadcast application.
Battelle Memorial Institute, 505 King Avenue, Columbus, OH 43201, USA.
William A
WA
Ivancic
Marcia G
MG
Nishioka
Russell H
RH
Barnes
Elaine Cohen
EC
Hubal
Michele
M
Morara
Steven M
SM
Bortnick
D002138:Calibration; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods*; D005456:Fluorescent Dyes; D006225:Hand; D006798:Housing; D006801:Humans; D007091:Image Processing, Computer-Assisted; D010573:Pesticide Residues / Q000032:analysis*; D012256:Riboflavin; D014741:Video Recording
D005456:Fluorescent Dyes; D010573:Pesticide Residues; D012256:Riboflavin