Airborne particulate matter (PM) is the primary environmental cause of death worldwide. The understanding of the toxicological mechanism has improved over the last decades, nonetheless now novel exposure systems allow the possibility to mimic the in vivo interaction between particles or particle constituents and lung cells. Here we report the results obtained after exposure to the organic extract of fine PM (PM_2.5-0.3) of the BEAS-2B cells cultured in submerged or at the air liquid interface (ALI) conditions. Deposition efficiency of both PM and its organic extract was followed. Cell viability, inflammatory responses and gene expression were then evaluated. The comparison of submerged vs ALI exposure revealed significant differences in the expression of specific genes such as CYP1A1 and NQO1 6h after exposure and CYP1B1 and NFkB1 24h post exposure. Also, the results demonstrate the importance of evaluating the efficiency of deposition of the treatment to avoid misinterpretation of the results. PM particles determined an extremely low deposition efficiency, making it impossible to use this particle for ALI exposure tests. Although biological results, such as gene expression, may vary between the two exposure approaches (submerged or ALI), the ALI exposure should be preferred as it is more representative of human exposure via the respiratory route.

In this work, PM_2.5 was sampled at Dunkerque, a medium-sized city located in northern France. The mean concentration of PM_2.5 during the sampling period was 12.6 ± 9.5 μg·m⁻³. Samples were analyzed for elemental and organic carbon (EC/OC), water-soluble organic carbon (WSOC), humic-like substances (HULIS-C), water-soluble inorganic ions, and major and trace elements. The origin and the variations of species concentrations were examined using elemental enrichment factors, bivariate polar plot representations, and diagnostic concentration ratios. Secondary inorganic ions were the most abundant species (36% of PM_2.5), followed by OC (12.5% of PM_2.5). Secondary organic carbon (SOC) concentrations were estimated to account for 52% of OC. A good correlation between SOC and WSOC indicated that secondary formation processes significantly contribute to the WSOC concentrations. HULIS-C also represents almost 50% of WSOC. The determination of diagnostic ratios revealed the influence of anthropogenic emission sources such as integrated steelworks and fuel oil combustion. The clustering of 72 h air masses backward trajectories data evidenced that higher concentrations of PM_2.5, OC, and secondary inorganic aerosols were recorded when air masses came from north-eastern Europe and the French continental sector, showing the considerable impact of long-range transport on the air quality in northern France.

This work focuses on filling the knowledge gap associated with the contribution of natural and anthropogenic marine emissions to PM₁₀ concentrations in northern France. For this purpose, a 1-year measurement and sampling campaign for PM₁₀ has been conducted at a French coastal site situated at the Strait of Dover. The characterization of PM₁₀ samples was performed considering major and trace elements, water-soluble ions, organic carbon (OC), elemental carbon (EC), and organic markers of biomass burning and primary biogenic emissions. Furthermore, the source apportionment of PM₁₀ was achieved using the constrained weighted non-negative matrix factorization (CW-NMF) model. The annual average PM₁₀ was 24.3 µg m⁻³, with six species contributing 69 % of its mass (NO${}_{\mathrm{3}}^{-}$ , OC, SO${}_{\mathrm{4}}^{\mathrm{2}-}$ , Cl⁻, Na⁺, and NH${}_{\mathrm{4}}^{+}$ ). The source apportionment of PM₁₀ led to the identification of 9 sources. On average yearly, fresh and aged sea salts contributed 37 % of PM₁₀, while secondary nitrate and sulfate contributed 42 %, biomass burning contributed 8 %, and heavy-fuel-oil (HFO) combustion from shipping emissions contributed almost 5 %. Additionally, monthly evolution of the sources' contribution evidenced different behaviors with high contributions of secondary nitrate and biomass burning during winter. In the summer season, 15-times-higher concentrations for HFO combustion (July compared to January) and the predominance of aged sea salts versus fresh sea salts were observed.The concentration-weighted trajectory model showed that the sources contributing more than 80 % of PM₁₀ at Cap Gris-Nez are of regional and/or long-range origins, with the North Sea and the English Channel as hotspots for natural and anthropogenic marine emissions and Belgium, the Netherlands, and the west of Germany as hotspots for secondary inorganic aerosols.

This comprehensive review synthesizes the current knowledge regarding the characteristics of particulate matter (PM) at locations directly impacted by industrial emissions. A particular emphasis was given to the morphology and size of these particles and their chemical characteristics per type of industrial activity. The relationship between the exposure to PM from industrial activities and health issues such as cancer, cardiovascular, and respiratory diseases was also discussed, highlighting significant epidemiological findings. Furthermore, this work highlights the source apportionment of PM in these areas as well as available databases for source profiles. The majority of the studies accentuate the ambiguity found in the identification of industrial sources mainly due to the lack of specific tracers and the overlapping between these sources and other natural and anthropogenic ones. The contribution of industrial sources to PM concentrations is generally less than 10%. Moreover, this review gathers studies conducted in the 18 countries of the East Mediterranean-Middle East (EMME) region, focusing on sites under industrial influence. In these studies, PM₁₀ concentrations range from 22 to 423 μg/m³ while PM_2.5 levels vary between 12 and 250 μg/m³. While extensive studies have been conducted in Egypt, Iran, and Lebanon, a lack of research in the UAE, Bahrain, Greece, Israel, Palestine, and Yemen highlights regional disparities in environmental health research. The major industrial sources found in the region were oil and gas industries, metallurgical industries, cement plants, petrochemical complexes, and power plants running on gas or heavy fuel oil. Future research in the region should focus on longitudinal studies and a more detailed chemical analysis of PM in the vicinity of industrial areas to enhance the accuracy of current findings and support effective policy making for air pollution control.