Visual Determination of Potential Dermal and Inhalation Exposure Using Allura Red As an Environmentally Friendly Pesticide Surrogate

Quantifying dermal and inhalation exposure to pesticides is a critical component of the decision-making procedure for risk evaluation. For traditional determination of pesticide exposure, a large amount of organic solvent is inevitably used to extract pesticides from the sampling medium. This paper presents an environmentally benign method for determining potential dermal and inhalation exposure using water-soluble Allura Red as a pesticide surrogate. Only water is used to extract the Allura Red from the sampling medium. More importantly, the operator can attain an immediate visual impression of the exposure patterns. This visual contaminant dispersion can be helpful for the development of measures to improve operational safety through pesticide management. For validation of the method, comparative exposure analyses were carried out with representative lipophilic and hydrophilic pesticides (chlorpyrifos and nitenpyram) under similar application conditions. The results indicate that Allura Red had similar exposure distributions to those of the pesticides. The total exposure measured using Allura Red is higher but of roughly the same order of magnitude as the values obtained with the pesticides. Combined with the calculated margin of exposure, this environmentally friendly method could provide a very useful reference for exposure risk assessment in various pesticide use scenarios.