Exposure Chambers for Studying the Partitioning of Atmospheric PAHs in Environmental Compartments: Validation and Calibration Using Experimental and Computational Approaches

Abstract

The environmental partitioning of atmospheric polycyclic aromatic hydrocarbons (PAHs) conditions their entry into food chains and subsequent risks for human health. The need for new experimental exposure devices for elucidating the mechanisms governing ecosystemic PAH transfer motivated the elaboration of an original small-scale exposure chamber (EC). A dual approach pairing experimentation and computational fluid dynamics (CFD) was selected to provide comprehensive validation of this EC as a tool to study the transfer and biological effects of atmospheric PAH pollution in microsystems. Soil samples and passive air samplers (PASs) were exposed to atmospheric pollution by phenanthrene (PHE), a gaseous PAH, for 2 weeks in examples of the EC being tested, set up under different conditions. Dynamic concentrations of atmospheric PHE and its uptake by PASs were simulated with CFD, results showing homogeneous distribution and constant atmospheric PHE concentrations inside the ECs. This work provides insight into the setting of given concentrations and pollution levels when using such ECs. The combination of experimentation and CFD is a successful ECs calibration method that should be developed with other semivolatile organic pollutants, including those that tend to partition in the aerosol phase.

Uptake Pathway, Translocation, and Isomerization of Hexabromocyclododecane Diastereoisomers by Wheat in Closed Chambers

“…These CV% values are less than those obtained in earlier studies using other types of passive air samplers, e.g., activated carbon. 25 In addition, a significant correlation was established between the PUF plugs measurements and C air , acquired from concentrations in the PUF plugs at the outlet, which indicated that PUF plugs at the outlet could reliably reflect the HBCDs concentrations in the air phase (R 2 = 0.916, p = 0.000; Figure S2).…”

“…The coefficient of variation (CV%) values for the measured concentrations recovered from the PUF plugs at various sites within the ECs were less than 5.97% (Table S5), indicating there existed adequate atmospheric HBCDs mixing in the ECs and the reproducibility of the PUF plugs. These CV% values are less than those obtained in earlier studies using other types of passive air samplers, e.g., activated carbon . In addition, a significant correlation was established between the PUF plugs measurements and C air , acquired from concentrations in the PUF plugs at the outlet, which indicated that PUF plugs at the outlet could reliably reflect the HBCDs concentrations in the air phase ( R 2 = 0.916, p = 0.000; Figure S2).…”

PAHs accumulation on leaves of six evergreen urban shrubs: A field experiment

“…In studying goals, the most suitable shrub for green urban spaces to efficiently moderate atmospheric pollution by PAHs can be selected. Given that the molecular weight of PAHs is related to their distribution among the gaseous phase and the particle-bond fraction of the atmosphere (low molecular weight PAHs are predominantly present in the gaseous phase while higher molecular weight PAHs are linked to the large particle fractions) (Desalme et al, 2013), the present study discriminates the pollutants according to the number of rings of which they are formed.…”