Seasonal variation of arsenic in PM10 and PMx in an urban park: The influence of vegetation-related biomethylation on the distribution of its organic species and air quality

Arsenic (As) levels in particulate matter (PM) are routinely monitored in cities of developed countries. Despite advances in the knowledge of its inorganic species in PM in urban areas, organic species are often overlooked with no information on their behaviour in urban parks – areas with increased potential for As biomethylation. Therefore, the aim of this study was to characterize As distribution, bioaccessibility, seasonal variation and speciation (As^III, As^V, MMA, DMA and TMAO) in PM_x–PM₁₀ of an urban park.

The original article

Seasonal variation of arsenic in PM₁₀ and PM_x in an urban park: The influence of vegetation-related biomethylation on the distribution of its organic species and air quality

Romana Michalicová, Václav Pecina, Jitka Hegrová, Martin Brtnický, Josef Svoboda, Lubomír Prokeš, Tivadar Baltazár, Roman Ličbinský

Chemosphere, Volume 362, August 2024, 142721

DOI: 10.1016/j.chemosphere.2024.142721

Two sites with different distance from the road were selected for winter and summer sampling. From the PM samples, we gravimetrically determined PM₁₀ concentrations in the air and via ICP-MS the total As content there. To assess the portion of bioaccessible As, water extractable As content was analysed.

Simultaneously, the As species in PM₁₀ water extracts were analysed via coupling of HPLC with ICP-MS method. There was no seasonal difference in PM₁₀ concentration in the park, probably due to the increased summer PM load related to recreational activities in the park and park design. Spatial distribution of total As in PM₁₀ and As fractional distribution in PM_x suggested that As mostly didn't originate from traffic although highest As content was observed in the fine fraction (PM_2.5) related to combustion processes. However, significant winter increase of As (determined by As^III and As^V) despite the unchanged concentration of PM₁₀ indicated a decisive influence of household heating-related combustion and possibly influence of reduced vegetation density. As present in the PM₁₀ was mostly in bioaccessible form.

Seasonal influence of As biomethylation was clearly demonstrated on the TMAO specie during the summer campaign. Except the significant summer TMAO increase, the results also indicated the biomethylation influence on DMA. Therefore, an increased risk of exposure to organic As species in urban parks can be expected during summer.

CDV: Seasonal variation of arsenic in PM10 and PMx in an urban park - The influence of vegetation-related biomethylation on the distribution of its organic species and air quality