Comparison of Atmospheric Travel Distances of Several PAHs Calculated by Two Fate and Transport Models (The Tool and ELPOS) with Experimental Values Derived from a Peat Bog Transect

Abstract

Multimedia fate and transport models are used to evaluate the long range transport potential (LRTP) of organic pollutants, often by calculating their characteristic travel distance (CTD). We calculated the CTD of several polycyclic aromatic hydrocarbons (PAHs) and metals using two models: the OECD P OV & LRTP Screening Tool (The Tool), and ELPOS. The absolute CTDs of PAHs estimated with the two models agree reasonably well for predominantly particle-bound congeners, while discrepancies are observed for more volatile congeners. We test the performance of the models by comparing the relative ranking of CTDs with the one of experimentally determined travel distances (ETDs). ETDs were estimated from historical deposition rates of pollutants to peat bogs in Eastern Canada. CTDs and ETDs of PAHs indicate a low LRTP. To eliminate the high influence on specific model assumptions and to emphasize the difference between the travel distances of single PAHs, ETDs and CTDs were analyzed relative to the travel distances of particle-bound compounds. The ETDs determined for PAHs, Cu, and Zn ranged from 173 to 321 km with relative uncertainties between 26% and 46%. The ETDs of two metals were shorter than OPEN ACCESSAtmosphere 2014, 5 325 those of the PAHs. For particle-bound PAHs the relative ETDs and CTDs were similar, while they differed for Chrysene.

Temporal and Spatial Trends of Polycyclic Aromatic Compounds in Air across the Athabasca Oil Sands Region Reflect Inputs from Open Pit Mining and Forest Fires

“…The selection of a 250 km radius reflects the size of the oil sands region and encompasses the areas that were affected by FFs. It is also consistent with the characteristic travel distance of PAHs (i.e., distance at which 63% of the chemical is removed from air) that is on the order of ∼100 km . The quantity of PAHs emitted from the FFs was converted into a comparable or “effective” average air concentration representing the 2-month deployment period of the passive sampler.…”

“…It is also consistent with the characteristic travel distance of PAHs (i.e., distance at which 63% of the chemical is removed from air) that is on the order of ∼100 km. 34 The quantity of PAHs emitted from the FFs was converted into a comparable or "effective" average air concentration representing the 2-month deployment period of the passive sampler. This was done by dividing the ∑PAH mass emitted from FFs by the volume of air estimated to pass through the control volume assuming an average wind speed of 9 km/h.…”

Air synthesis review: polycyclic aromatic compounds in the oil sands region

“…Owing to the complex interactions among these phenomena, atmospheric lifetimes are highly variable, depending on emission height, wind speed, vertical mixing, temperature, water vapor content, ultraviolet radiation, and the presence or absence of other reactive compounds. The Environmental Long-range Transport and Persistence of Organic Substances (ELPOS) model (Beyer and Matthies 2002) attempts to simulate these interactions and has been used in eastern Canada to estimate PAC travel distances and lifetimes (Thuens et al 2014). ELPOS was applied retrospectively to PACs and trace metals in peat bogs relative to long-term emissions from the Sudbury smelter.…”

Colonialism and the environment: The pollution legacy of the Southern Hemisphere’s largest copper mine in the 20th century

“…A number of complaints were issued by local residents about the sulphur fumes emitted during the period of pyritic smelting (between 1896 -1922), demonstrating the extent of metal emissions during this time (Rae, 1994). However, the metals from smelters are in smaller/lighter forms and have a longer atmospheric transport range (Ghayoraneh and Qishlaqi, 2017;Rasmussen, 1998;Roy et al, 2019;Thuens et al, 2014) while metal emission to the atmosphere from open-cut mining occurs mainly as dust and particulate emissions (Despić and Popov, 1972;Weng et al, 2012), and are more likely to be deposited in the nearby lakes.…”