Cadmium (Cd) is a metallic pollutant which has been classified as a possible pancreatic carcinogen. Cd uses similar ion channels than divalent cations to accumulate into the cells. These include the Transient Receptor Potential Cation Channel Subfamily M Member 7 (TRPM7) which has been also shown as a biomarker of pancreatic cancer. Pancreatic carcinogenesis is associated with the establishment of a fibrous stroma induced by pancreatic stellate cell (PSC) activation. Although several stress factors have been identified as activators of PSCs, the impact of pollutants, particularly Cd, is still unknown. Here, we chronically exposed human PSCs to Cd and we observed that Cd-exposed cells acquired a myofibroblast-like phenotype. Moreover, TRPM7 expression and activity were upregulated following Cd exposure. Both TRPM7 inhibition by silencing or NS8593 treatment prevented the Cd-induced PSC cell migration indicating that TRPM7 regulated PSC activation. We used a model of indirect co-culture to study the impact of PSC on MIA PaCa-2 cancer cell migration. Interestingly, we showed that Cd-exposed PSCs stimulated MIA PaCa-2 cancer cell migration to a greater extent than non-exposed PSCs. TRPM7 inhibition in PSCs abolished the migration of cancer cells. Finally, in a mouse model with the KRASG12D mutation inducing spontaneous pancreatic intraepithelial neoplasia, Cd exposure aggravates collagen deposition in fibrotic areas showing high α-SMA and TRPM7 expressions. In summary, our study showed that Cd exposure upregulates TRPM7 leading to PSC activation and aggravation of precancerous pancreatic fibrosis in vivo.

Abstract. Oxidative potential (OP) of atmospheric particulate matter (PM) is a metric of increasing scientific interest because it potentially links chemical particle properties to particle health effects. OP has been recently introduced as a recommended monitoring metric in the European Air Quality Directive. However, inconsistent protocols in the existing literature make it difficult to compare results across studies. Following a 2023 inter-laboratory comparison that focused on PM OP measured using the dithiothreitol (DTT) assay, this paper presents the findings and lessons learnt from a second inter-laboratory study focused on the ascorbic acid assay (OP-AA). In this study, twenty-six laboratories worldwide quantified OP of four PM filter samples and of one chemical compound to evaluate the entire analytical chain, including the extraction step, using a simplified OP-AA protocol. While most laboratories produced repeatable internal results when applying the simplified protocol, significant discrepancies between participants highlight the need for each laboratory to carefully evaluate deviations from the simplified OP-AA protocol. Over half of the 26 participants achieved satisfactory results, suggesting that the protocol is suitable for large-scale implementation. Beyond assessing performance, this work investigates technical, analytical, and mathematical refinements to measurement protocols. Building on the first DTT assay study, this second inter-laboratory comparison represents a significant step toward harmonizing OP assays, and provides specific recommendations to ensure consistent future measurements, ready to be applied in the new air quality directive EU 2024/2881.

This study presents a comprehensive chemical characterization and source apportionment of PM2.5 in the Greater Cairo Area (GCA), one of the world's most polluted megacities. A total of 59 PM2.5 samples were collected continuously and on a 24-h basis during the winter of 2019-2020 at an urban background site and analyzed for a wide range of organic and inorganic species. The Positive Matrix Factorization (PMF) model was applied to identify and quantify as many as eleven sources contributing to PM2.5, highlighting the highly complex mixture of aerosols over the GCA. These sources include industrial emissions (coal combustion, lead and copper smelting), vehicular exhaust and non-exhaust emissions, open waste and wood burning, cooking, processed secondary aerosols, transported crustal dust, and mixed regional pollution. Local primary particulate controllable sources dominated elemental health risks, contributing 60% of the total non-cancer risk (NCR:1.7) and 52% of the total cancer risk (CR:2.1 & times; 10(-5)), despite representing a much smaller fraction of PM2.5 mass. Industrial emissions, though contributing only similar to 12% of PM2.5 mass, were responsible for 37% of elemental NCR and 29% of CR. These findings underscore the need for targeted mitigation strategies addressing the burden of air pollution in GCA.

This study examines PM2.5 oxidative potential (OP) measurements, assessed using the ascorbic acid (OP-AA) and dithiothreitol (OP-DTT) assays, at Eastern Mediterranean sites, in conjunction with detailed chemical characterization and source apportionment data. The dataset includes around 300 samples collected from various sites under different influences (urban, suburban, and urban-industrial). Average OP-AAv values varied between 0.41 and 0.79 nmol min-1 center dot m-3, while average OP-DTTV varied between 0.26 and 0.49 nmol min-1 center dot m-3. A multiple linear regression method was applied to estimate the contribution of PM sources to OP values at each site. The results showed that this approach was effective to reconstruct observed OP for both assays. Among the common sources identified, traffic non-exhaust, biomass burning, and Heavy Fuel Oil (HFO) combustion sources exhibited the highest intrinsic OP (OPm) for both assays. Additionally, diesel generators source showed a notable contribution to OPm-AA. Conversely, sea-salts and crustal dust sources had the lowest OPm. Additionally, other sources such as secondary organic aerosols and open waste burning showed significant OPm values. In terms of OPv contribution, road traffic, biomass burning, HFO combustion and ammonium sulfate emerged as the dominant contributors at all sites, collectively accounting for more than 70 % of the observed OP for both assays.

Protests have become a global phenomenon, with road blockades among the most common methods used to express objection. In many countries, these blockades involve the open burning of materials such as tires, wood, and waste. In this study, PM2.5 was collected during an active burning protest episode as well as over the subsequent days. PM2.5 was characterized for the carbonaceous fraction, water-soluble ions, elements, and organic compounds (alkanes, polycyclic aromatic hydrocarbons (PAHs), phthalates, fatty acids, hopanes, levoglucosan, dioxins, furans, and dioxin-like polychlorobiphenyls (PCDD/Fs and DL-PCBs). The major contributors to PM2.5 during the burning episode were elemental carbon, organic carbon, and zinc, which collectively accounted for 42% of total PM2.5. The chemical profile also revealed a marked increase in combustion-related compounds such as alkanes, PAHs, PCDD/Fs, and DL-PCBs, highlighting the strong influence of open burning emissions on air quality. Oxidative potential (OP) assays showed a clear increase during the burning day, with peak values of 6.6 nmol/min/m3 for OP-DTT and 5.8 nmol/min/m3 for OP-AA. While these OP levels were nearly double those of non-burning days, the increase was notably less pronounced compared to the sharp fluctuations observed in chemical tracers and toxic equivalents. The temporal trends also indicated differing sensitivities between the assays, with OP-DTT more closely following OC levels, while OP-AA was more influenced by EC and elemental content. These findings highlight the complex chemical nature of emissions from protest-related burning and underscore the need for non-toxic alternatives to such practices.

While many studies on the health effects of PM2.5 exist, the risks of PM2.5 species remain largely unexplored in Middle Eastern and North African countries. This study assesses, for the first time, the carcinogenic and non-carcinogenic health risks for elements, polycyclic aromatic hydrocarbons (PAHs), phthalates, polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs) bound to PM2.5 in the Greater Cairo Area. A total of 59 samples were collected from an urban site in Dokki (November 2019–January 2020). Chemical analysis showed higher concentrations of PCDFs (5418 fg/m3) than PCDDs (1469 fg/m3), with DL-PCBs being the most abundant (6577 fg/m3). Health risk assessment for inhalation showed non-carcinogenic risks for all age groups, especially for newborns. Manganese (Mn) and lead (Pb) posed the highest elemental non-carcinogenic risk, while the hazard quotient (HQ) for PAHs exceeded 1 across all ages. PCDDs, PCDFs, and DL-PCBs showed an estimated cancer risk reaching 10−6 in adults, indicating a significant health concern. Key contributors to cancer risk included arsenic (As), chromium (Cr(VI)), and vanadium (V), which accounted for over 80% of the total elemental cancer risk. Major and trace elements posed the highest lifetime cancer risk, nearly 37 times the acceptable level.

Diesel generators, widely used in developing countries, compensating for long power outages and blackouts, are significant sources of air pollution. In this study, diesel exhaust particulate matter (DEPM) samples were collected from two midsize generators operating in Beirut by cascade impaction, and gravimetrically analyzed for size. The smallest fraction captured on quartz filter was then chemically characterized for its constituents, and examined for its cytotoxicity on 2D and 3D human uroepithelial cell cultures. Results showed that 87 % of collected PM are quasi-ultrafine (<0.33 mu m in diameter), and marked high emissions of organic and elemental carbon (OC/EC), elements and metals, particularly Ca, Fe, S, Al, and Ti, and polyaromatic hydrocarbons (PAHs), mainly Benzo[g,h,i]perylene and Dibenzo[a,h]anthracene, as well as high emissions of dioxins, furans and polychlorinated biphenyls (PCBs), particularly OCDD, 1,2,3,4,6,7,8 HpCDF, and PCB118. In addition, in vitro testing showed decreased proliferation, viability, and spheroid formation ability only at high concentrations. In conclusion, DEPM from domestic generators consists of a wide panel of potent toxicants, notably genotoxic, carcinogenic, and endocrine disrupting compounds. Additionally, in vitro results provide a solid basis to further examine the potential contribution of DEPM to bladder tumorigenesis in established cell culture models.

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 PM2.5 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.

In this work, PM2.5 was sampled at Dunkerque, a medium-sized city located in northern France. The mean concentration of PM2.5 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 PM2.5), followed by OC (12.5% of PM2.5). 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 PM2.5, 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.

Fine particles (PM2.5) have generally been reported as the major contributor to the adverse health effects of air pollution. Lebanon is characterized by a high density of transport, the production of electricity by generators, and a problem of uncontrolled incineration of household waste. For the purpose of this paper, the physico-chemical properties of fine (PM2.5-0.3) and quasi-ultrafine (PM0.3) particulate matter sampled in Southern Lebanon, were studied. Then, an evaluation and comparison of the toxicity of the different extracted fractions from PM (i.e., native PM2.5-0.3 vs. organic extractable matter fraction (OEM2.5-0.3), and non-extractable matter fraction (NEM2.5-0.3)) was performed. Also, an examination of the toxicity of PM0.3 was conducted indirectly through the evaluation of the OEM0.3 harmfulness. The physico-chemical analysis showed that PM0.3 was much more concentrated than PM2.5-0.3 in organic compounds such as polycyclic aromatic hydrocarbons (PAHs) (28-fold) and their nitrated (N-PAHs, 14-fold) and oxygenated (O-PAHs, 10-fold) derivatives. Normal human bronchial epithelial cells (BEAS-2B) were exposed to PM2.5-0.3, its derived fractions (i.e., OEM2.5-0.3 and NEM2.5-0.3), and OEM0.3 before evaluating the global cytotoxicity, metabolic activation of organic compounds, genotoxicity, and inflammatory response. Different responses were observed depending on the considered fraction of particles. The global cytotoxicity showed a pronounced response related to ATP and LDH activities after exposure to the quasi-ultrafine organic extractable matter fraction (OEM0.3). There was no significant induction of the AhR cell-signaling pathway by NEM2.5-0.3. Despite the apparent difference in the kinetics of induction of the toxicological endpoints under study, OEM0.3 provoked a higher overall cytotoxicity and genotoxicity than OEM2.5-0.3 and total PM2.5-0.3. Taken together, these results clearly showed that the finest particles are more damaging to BEAS-2B cells than PM2.5-0.3 because they are richer in organic compounds, thereby inducing more remarkable toxic effects.

This work presents an exhaustive chemical characterization of the organic fraction of fine particulate matter (PM2.5) collected at an urban site in the Greater Cairo Area, Egypt, one of the most polluted megacities in the world. An intensive 2-month sampling campaign was conducted at an urban site in Giza (Dokki), from November 26, 2019, to January 28, 2020. Daily (24-h integrated) PM2.5 filter samples were then analyzed for their carbonaceous (OC, EC) and organic fractions including primary (n-alkanes, phthalates, fatty acids, polycyclic aromatic hydrocarbons, hopanes, sugars, and sugar alcohols) and secondary (isoprene and β-caryophyllene oxidation products, and dicarboxylic acids) compounds. Average organic (OC) and elemental carbon (EC) concentrations were 17.8 ± 6.6 μg/m3 and 4.4 ± 1.5 μg/m3, respectively. Biomass burning was confirmed by high daily concentration levels of levoglucosan, mannosan, and galactosan (sum equals to 288 ng/m3). Road traffic was also highlighted by the relative abundance of tetracosane and a carbon preference index close to unity as well as by the concentration ratios of PAHs and hopanes. Moreover, phthalates were identified for the first time in Cairo with high concentrations (654 ng/m3) that might be attributable to open waste burning activities. Fatty acids and sugars were also investigated and assigned to cooking activities and primary biogenic sources, respectively. The average concentration of isoprene and β-caryophyllene oxidation products were 0.89 ± 0.83 ng/m3, and 0.01 ± 0.02 ng/m3, respectively. These low values are expected since no pine trees or even forests exist in Egypt. The macrotracer approach was employed alongside Monte Carlo simulation to identify sources of primary OC and evaluate the uncertainties associated with source attribution and OC reconstruction. The findings revealed a strong contribution from cooking (31% of observed OC) and biomass burning (18%), with median reconstructed OC levels showing significant uncertainty (64%) as expected.

This study aimed to evaluate the oxidative potential (OP) of PM(2.)5 collected for almost a year in an urban area of the East Mediterranean. Two acellular assays, based on ascorbic acid (AA) and dithiothreitol (DTT) depletion, were used to measure the OP. The results showed that the mean volume normalized OP-AAv value was 0.64 +/- 0.29 nmol center dot min(-1)center dot m(-3) and the mean OP-DTTv was 0.49 +/- 0.26 nmol center dot min(-1)center dot m(-3). Several approaches were adopted in this work to study the relationship between the species in PM2.5 (carbonaceous matter, water-soluble ions, major and trace elements, and organic compounds) or their sources and OP values. Spearman correlations revealed strong correlations of OP-AAv with carbonaceous subfractions as well as organic compounds while OPDTTv seemed to be more correlated with elements emitted from different anthropogenic activities. Furthermore, a multiple linear regression method was used to estimate the contribution of PM2.5 sources, determined by a source-receptor model (Positive Matrix Factorization), to the OP values. The results showed that the sources that highly contribute to the PM2.5 mass (crustal dust and ammonium sulfate) were not the major sources contributing to the values of OP. Instead, 69 % of OP-AAv and 62 % of OP-DTTv values were explained by three local anthropogenic sources: Heavy Fuel Oil (HFO) combustion from a power plant, biomass burning, and road traffic emissions. As for the seasonal variations, higher OP-AAv values were observed during winter compared to summer, while OP-DTTv did not show any significant differences between the two seasons. The contribution of biomass burning during winter was 33 and 34 times higher compared to summer for OP-AA(v) and OP-DTTv, respectively. On the other hand, higher contributions were observed for HFO combustion during summer.

The characterization and the source apportionment of PM10 data have been used for the article "Measurement report: A one-year study to estimate maritime contributions to PM10 in a coastal area in Northern France," which is under revision in the journal Atmospheric Chemistry and Physics.

The aim of this work was to study the relationship between oxidative stress damages and particulate matter (PM) chemical composition, sources, and PM fractions. PM2.5-0.3 (PM with equivalent aerodynamic diameter between 2.5 and 0.3 μm) were collected at urban, road traffic and industrial sites in the North of France, and were characterized for major and minor chemical species. Four different fractions (whole PM2.5-0.3, organic, water-soluble and non-extractable matter) were considered for each of the PM2.5-0.3 samples from the three sites. After exposure of BEAS-2B cells to the four different fractions, oxidative stress was studied in cells by quantifying reactive oxygen species (ROS) accumulation, oxidative damage to proteins (carbonylated proteins), membrane alteration (8-isoprostane) and DNA damages (8-OHdG). Whole PM2.5-0.3 was capable of inducing ROS overproduction and caused damage to proteins at higher levels than other fractions. Stronger cell membrane and DNA damages were found associated with PM and organic fractions from the urban site. ROS overproduction was correlated with level of expression of carbonylated proteins, DNA damages and membrane alteration markers. The PM2.5-0.3 collected under industrial influence appears to be the less linked to cell damages and ROS production in comparison with the other influences.

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 nonnegative matrix factorization (CW-NMF) model. The annual average PM10 was 24.3 mu gm(-3), with six species contributing 69% of its mass (NO3-, OC, SO42-, Cl-, Na+, and NH4+). 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.