Seasonal distribution of PM2.5-bound polycyclic aromatic hydrocarbons as a critical indicator of air quality and health impact in a coastal-urban region of Poland

Summertime Characteristics of Atmospheric Polycyclic Aromatic Hydrocarbons in a Coastal City of Northern Poland

Parent polycyclic aromatic hydrocarbons (PAHs) in the gas and particle fraction were measured between May and August 2021 at a coastal urban site in Poland, to examine their chemical characteristics, distribution, sources, deposition fluxes and interactions with basic meteorological drivers. The mean concentration of PAHs in the gas phase was significantly higher (26.26 ± 15.83 ng m^-3) than levels measured in the particle phase (1.77 ± 1.26 ng m^-3). The highest concentration in the gas phase was found for phenanthrene (Phe), followed by fluoranthene (Flt), acenaphthene (Ace) and naphthalene (Naph). The contribution from each group of PAHs to the total particulate phase accounted for 50%, 25%, 14% and 12% for 3-, 4-, 5- and 6-ring compounds, respectively. The mean ΣPAH deposition flux was 59 ± 24 ng m^-2 day^-1. During the whole field campaign, the efficient removal of PM-bound PAHs was typically observed after precipitation events. Based on statistical analysis, it was found that 4-ring PAHs were less effectively removed (25%) by daily precipitation as compared to 5- and 6-ring components, whose fluxes decreased by 32% and 53%, respectively. This study revealed local urban sources such as vehicular emissions, coal-fired power plants, shipping activities, docks/ports infrastructure and municipal solid waste recycling units as predominant contributors to PM-bound and gas-phase PAHs.

Ratio fluorescence sensor based on CD/Cu-MOFs for detection of Hg2

Trace detection of toxic heavy metals is a very important and difficult problem in several areas: convenience, sensitivity, and reliability. Herein, we develop an innovative fluorescence resonance energy transfer (FRET)-based ratio fluorescence sensor for the detection of heavy metal mercury ion (H g ²⁺). The sensing platform is composed of coumarin derivatives (CDs) and a copper metal-organic framework (Cu-MOF) named CD/Cu-MOF. The constructed CD/Cu-MOFs ratio fluorescence sensor exhibits dual emission peaks at 430 and 505 nm under the single excitation wavelength of 330 nm. With the addition of H g ²⁺, the fluorescence intensity of the system at 430 nm gradually increased, and the fluorescence intensity at 505 nm remained stable, resulting in a change in the fluorescence ratio. There is a good logarithmic relationship between the H g ²⁺ concentration in the range from 2×10^-8 to 0.001 nM and the ratio of the fluorescence emission intensity of the system (F ₄₃₀/F ₅₀₅) (R ²=0.9901), and its calculated detection limit is 3.76×10^-9 n M. In addition, the CD/Cu-MOFs ratio fluorescence sensor has achieved a good recovery rate of standard addition in the actual food sample recovery experiment, which provides an effective method for the detection of H g ²⁺ in food samples.

Polycyclic aromatic hydrocarbons in coarse particles (PM10) over the coastal urban region in Poland: Distribution, source analysis and human health risk implications

In this study, the results of PM10-bound PAH measurements were subjected to positive matrix factorization (PMF) approach and diagnostic ratios to investigate their levels, seasonal variability, impact of primary anthropogenic sources, and human health risk via the inhalation route. Daily ground-based observations were carried out at a representative coastal site in Gdynia (northern Poland), from April to December 2019. The concentrations of Σ13PAHs in PM10 varied between 0.45 ng m-3 and 54.02 ng m-3, with a mean of 5.22 ± 8.67 ng m-3. A clear seasonality and distribution profiles of PM10-bound PAHs were observed as a result of local/remote sources and meteorological conditions. The highest Σ13PAH concentration was found in December (18.56 ± 16.45 ng m-3) and the lowest values were observed between June and September (3.89 ± 0.52 ng m-3). The PMF-based analysis revealed five factors, suggesting the importance of primary anthropogenic sources of PAHs, i.e. coal combustion, biomass burning, gasoline/diesel vehicles, industrial and shipping activities as well as natural gas combustion. In summer, PAH levels were mostly controlled by local shipping emissions as well as traffic-related and non-combustion sources such as photochemical decomposition. The winter PAH maxima were attributed to a strong increase in residential coal combustion. A Spearman's rank correlation and multilinear regression analysis showed that ambient temperature and NO× had a significant impact on intra-annual variability in PM10-bound PAH transformation in this region. PAH congeners in coarse-size fraction were positively correlated with SO2, indicating their shared anthropogenic sources. The annual mean of epidemiologically based ILCR value was 6.6 × 10-5. This work indicates a potential carcinogenic risk for the local population and a significant difference in BaPeq levels between the individual seasons in this region.

Compositional and seasonal differences of gas and particle phase polycyclic aromatic hydrocarbons (PAHs) over the southern Baltic Sea coast

In this study, 16 USEPA-prioritized PAHs in gas- and particle-phase (PAH_g+p), associated chemical and meteorological parameters, and backward trajectory simulations were explored in a coastal city in Poland, between April 2019 and May 2020. This study reports several important aspects of PAH_g+p, i.e. variation, composition, distribution profiles, impact of weather conditions, and correlation analysis between target PAH compounds and influencing inorganic gaseous pollutants. Specifically, higher and more variable concentrations of total PAH_g+p (mean ± SD, ng m^-3) were observed during winter (36.38 ± 24.19) compared to autumn (22.3 ± 17.44), summer (21.52 ± 13.30) and spring (19.90 ± 13.13). A distribution profile of parent PAH_g+p was as follows: 3-ring > 4-ring > 2-ring > 5-ring > 6-ring, although their relative contribution to the total PAHs showed statistically significant differences between seasons (p < 0.05). Precipitation-driven loss of ΣPAH_g+p was lower in the warm period than in the cold one, reflecting higher PAH concentrations in winter. A seasonal model-based analysis of incremental lifetime cancer risk showed a higher potential cancer risk for children than those for adult females and males. The adverse health impacts associated with PAH exposure via inhalation route indicate the need for implementation of pollution-control policies in this region.