Fugacity-Based Indoor Residential Pesticide Fate Model

Abstract

Dermal and non-dietary pathways are potentially significant exposure pathways to pesticides used in residences. Exposure pathways include dermal contact with residues on surfaces, ingestion from hand-and object-to-mouth activities, and absorption of pesticides into food. A limited amount of data has been collected on pesticide concentrations in various residential compartments following an application. But models are needed to interpret this data and make predictions about other pesticides based on chemical properties. In this paper, we propose a mass-balance compartment model based on fugacity principles. We include air (both gas phase and aerosols), carpet, smooth flooring, and walls as model compartments. Pesticide concentrations on furniture and toys, and in food, are being added to the model as data becomes available. We determine the compartmental fugacity capacity and mass transfer-rate coefficient for wallboard as an example. We also present the framework and equations needed for a dynamic mass-balance model.

Ventilation Relevant Contaminants of Concern in Commercial Buildings Screening Process and Results

“…Chemicals with a high chemical affinity for carpets, walls, and furniture will not be effectively removed from the indoor environment by ventilation. In order to rank chemicals in terms of their capacity or recalcitrance for being removed by ventilation, we adapted the indoor mass-balance model of Bennett and Furtaw (2004). The model was modified so that it could be used for commercial environments rather than residential environments and we used it to make relative rankings rather than absolute determinations of chemical mass balance.…”

“…The model was modified so that it could be used for commercial environments rather than residential environments and we used it to make relative rankings rather than absolute determinations of chemical mass balance. The Bennett and Furtaw (2004) model is an indoor fugacity model that uses indoor sources or transfers of chemicals from outdoor sources to assess the relative partitioning of chemicals among the major indoor media--air, dust, and surfaces (carpets, vinyl floors, walls, and ceilings). Bennett and Furtaw (2004) showed good comparison of their results with measurements of chlorpyrifos in air and carpets from an independent study.…”

“…The Bennett and Furtaw (2004) model is an indoor fugacity model that uses indoor sources or transfers of chemicals from outdoor sources to assess the relative partitioning of chemicals among the major indoor media--air, dust, and surfaces (carpets, vinyl floors, walls, and ceilings). Bennett and Furtaw (2004) showed good comparison of their results with measurements of chlorpyrifos in air and carpets from an independent study. The elements of the Bennett and Furtaw model that are important for our screening study are the model framework for mass balance and the data needed to determine the retention (fugacity) capacities of air, particles, and surfaces.…”

“…The Bennett and Furtaw model includes mass transfer models, parameters, and materials properties needed to assess chemical partitioning for indoor air (both gas phase and aerosols), carpet, smooth flooring (vinyl), and walls. Although Bennett and Furtaw (2004) used six size fractions of particulate matter with different fate and transport properties, only one size category was used for the assessment here. The compartment-specific fugacity capacities and their mass transfer rate coefficients between compartments listed in Bennet and Furtaw (2004) were used.…”

Insecticide Exposures on Commercial Aircraft: A Literature Review and Screening Level Assessment

“…What is unique to the application of pyrethroids on aircraft is that knowledge about exposure is almost completely lacking. A large number of pyrethroid applications have been studied to characterize potential exposure [35][36][37][38][39][40][41][42] but only a few studies have considered applications on aircraft [17,18] and these are focused on a single application method (aerosol disinsection). Information on residual treatment or treatments used in the domestic fleet are completely lacking.…”