School handwashing facilities in rural areas without piped water and drainage systems often discharge wastewater directly into the ground, leading to environmental contamination and loss of a valuable water resource, particularly in water-scarce regions. This study evaluates a decentralised three-stage handwashing wastewater treatment system combining biochar and sand filtration with chlorination. The integrated system effectively improved water quality by reducing turbidity, colour, suspended solids, nutrients, organic matter, and microbial contamination. While biochar and sand filtration provided substantial physicochemical treatment, chlorination was essential to ensure complete microbial inactivation. The treated water met several water quality standards for potable use (handwashing only) set by the World Health Organization (WHO) and the United States Environmental Protection Agency (USEPA) standards. Additionally, it complied with international guidelines for greywater reuse in toilet flushing, irrigation, and floor washing. This innovative water treatment strategy could help clean and reuse handwashing wastewater on-site. This could provide rural schools with clean water to support water needs in water shortage periods, such as hand hygiene, garden irrigation, toilet flushing, and floor washing. Overall, integrating biochar and sand filtration with disinfection could help remote rural schools recover water, advancing towards the achievement of the Sustainable Development Goals (SDG) for good health (SDG 3), clean water and sanitation (SDG 6), and sustainable communities (SDG 11).

Seven UK air pollution control residues (APCRs) from municipal solid waste combustion were examined to understand the speciation of potentially ecotoxic zinc, before and after partial APCR neutralisation using acid wastes, as is sometimes conducted before disposal. Fe K-edge XAS showed Zn-containing magnetite (spinel) is an important phase in APCRs, along with ferrihydrite. Linear combination fitting of X-ray absorption near edge structure (XANES) Zn K-edge spectra strongly concluded that the 2600-7300 mg kg-1 of zinc in APCRs is speciated mainly as spinel, hemimorphite, a glassy phase, zinc phosphate and hydrozincite, with statistically consistent findings both within and between APCRs. The extended X-ray absorption fine structure (EXAFS) spectra of APCR mainly show the first Zn-O shell which is consistent with Zn in solid solution, glass and poorly crystalline phases. Presented in the context of a full review of previous studies, these results suggest changes in Zn speciation under modern operating regimes. pH-dependent leaching behaviour of the raw APCRs was consistent with solubility control by secondary Zn(OH)2 over the alkaline range, and also Zn5(OH)8Cl and hydrozincite at mid-alkaline pH. Partial neutralisation of the APCRs with concentrated HCl formed secondary reaction products that agglomerated the APCRs, but the same zinc species were found after neutralisation, and lower zinc leachability is attributable only to decreasing the pH to 10.0-10.7. Since this pH is unlikely to be stable in the environment (e.g., in interaction with landfill leachate at pH 5-8), industrial "treatment" by partial neutralisation does not reduce the environmental risk associated with zinc in APCRs.

Phthalate esters (PAEs) are ubiquitous synthetic chemicals, known pollutants and health hazards. Due to their adverse health effects, including those associated with inhalation exposure, PAEs have been relatively well studied in outdoor particulate matter with aerodynamic diameter <2.5 mu m (PM2.5). However, limited data exist on indoor emissions of PAEs, despite the fact that nearly 90 % of human daily activities occur indoors, indicating a potential gap in understanding human exposure to those pollutants. This pilot study aimed to perform a preliminary assessment on the presence of six priority PAEs and the alternative plasticiser bis-(2-ethylhexyl) adipate (DEHA) in indoor PM2.5 from three offices in the UK and Brazil. DEHP (bis-(2-ethylhexyl) phthalate), was consistently detected in PM2.5 (with concentrations up to 34 ng/m(3)) from all studied offices. DEHP concentrations had consistently low airborne variability, especially within the occupied offices, suggesting that human activities could facilitate the continuous resuspension of DEHP-bound particles, maintaining a steady-state indoor concentration. Although mean DEHP levels in all studied offices were below the UK HSE workplace exposure limit, they represent a continuous chronic exposure source not accounted for by industrial safety standards. Reliance on oral reference values due to unavailability of inhalation reference standards for PAEs may underestimate risks due to route-specific metabolic differences. The study provides the first region specific data from the UK and Brazil suggesting indoor environments as contributors to PM2.5-bound DEHP exposure, highlighting the need for more systematic and long-term monitoring initiatives.

Poly- and perfluoroalkyl substances (PFAS) are persistent chemicals that may pose risks to ecosystems and human health. Understanding the environmental fate and transport of PFAS is challenging due to their ability to migrate across air, water, and soil. In surface waters, PFAS can interact with sediments, organic matter, and plants, influencing the mobility of these compounds and posing potential risks to the environment. This study provides the first analysis of the adsorption of PFAS, including perfluoro-carboxylic acids (PFCA, C4–C10), perfluoro-sulfonic acids (PFSA, C4–C8), per-/poly-fluoroalkylether acids (PFEA C4-C8) and fluorotelomer sulfonates (FTS, C8 and C10) to medium-sized quartz gravel (pebbles), commonly found in the UK river systems. The effects of exposure time (1, 3 and 7 days) and mechanical disturbance (shaking) on PFAS adsorption were evaluated. The degree of PFAS adsorption indicated a clear dependence on the compound’s functional group and carbon chain length. Long-chain PFAS, perfluorodecanoic acid (PFDA), exhibited the highest adsorption, while PFCA showed the least sorption compared to corresponding PFEA, PFSA and FTS of homologues (C5–C8). Mechanical disturbance (shaking) of gravel in PFAS-contaminated water did not significantly influence the extent of adsorption on most of the studied analytes except 9 Cl-PF3OUdS, 8:2 FTS, and PFDA, onto the gravel. The study demonstrates, for the first time, that medium-sized quartz gravel can adsorb PFAS, including new-generation substitutes from water. In riverine systems, these pollutants can be remobilised from gravel surfaces during e.g., flooding, dredging, or changes in water chemistry, potentially reintroducing them into the water and impacting water quality and ecosystem.

Water scarcity affects water availability in Peruvian rural schools without piped systems, yet the perspectives of rural students on school greywater treatment and reuse are mainly unexplored. This study explores students' perceptions, willingness, and concerns from three rural schools in Pichihua, Socco, and Yanaca (Apurimac Region, Peru) regarding greywater treatment and reuse. Using semi-structured questionnaires answered by 167 secondary students, the study found frequent water shortages (57% weekly) affecting hygiene and sanitation. There was high acceptance for greywater treatment systems (88%), significantly influenced by age and gender (p < 0.05). Students supported reusing treated greywater for handwashing (86%), cleaning (73.2%), garden watering (69%), and toilet flushing (65%). Over half were willing to use treated water for handwashing if it was pathogen-free (51.6%) and high quality (47.7%). Main concerns involved health risks (36%) and water appearance (28%). Recommendations included training on greywater treatment (40%) and regular quality assessments (35%) to mitigate concerns. This study shows that implementing a greywater treatment system is socially feasible for addressing water shortages in rural schools. The findings can help water technology developers create strategies to enhance benefits and reduce risks of reusing treated greywater while supporting policy development for water reuse in rural communities. [GRAPHICS] .

Pollen-induced allergic diseases are on the rise globally with recent studies pointing towards climate change co-factors potentially influencing pollen seasons and pollen load. This study investigated the hydration-induced rupturing behaviour and allergenic potential of pollen belonging to species of ryegrass (Lolium perenne), golden wattle (Acacia pycnantha) and pine (Pinus radiata). Using an in vitro model of human bronchial epithelial cells (Calu-3), this study evaluated cellular responses upon exposure to pollen extracts through multiple experimental approaches. Initial hydration experiments revealed species-specific rupturing patterns. Ryegrass pollen demonstrated the highest rupture propensity (38% immediately upon hydration), with increased rupturing over time and enhanced effects in acidic conditions. Wattle exhibited moderate rupturing that plateaued after 10 min, while pine pollen showed minimal rupturing (≤2%). Nebulisation of hydrated pollen-water suspensions generated distinct aerosol profiles, with ryegrass producing significant numbers of sub-pollen particles in the respirable range. Cell viability of Calu-3 cells showed varied concentration-dependent responses among pollen species. Pine pollen induced the most significant reduction in cell viability (51% at 25 mg/mL pollen extract concentration), followed by ryegrass and wattle pollen. Notably, ryegrass pollen uniquely triggered substantial reactive oxygen species (ROS) production, with rates increasing up to 33.8 times greater than controls at 25 mg/mL pollen extract concentration. This elevated ROS generation correlated with increased group 5 grass allergen (Phl p 5) levels (53.8 ng/mL at 25 mg/mL pollen extract concentration), suggesting a potential mechanistic link. In contrast, cell viability of Calu-3 cells was greater than 70% in the presence of wattle pollen with only a slight increase in cellular ROS generation, suggesting other mechanisms are involved in maintaining cell viability in this species. This research establishes a foundation for understanding cellular responses to pollen extracts of different species, including the impact of physical characteristics (rupture propensity and sub-pollen particle generation) and biochemical properties (ROS induction and allergen content), which can both contribute to overall allergic potential. The species-specific responses identified will also have important implications for clinical management strategies, particularly in the context of changing climate conditions.

Phthalate esters (PAEs) such as dimethyl phthalate (DMP), diethyl phthalate (DEP), bis-2(ethylhexyl) phthalate (DEHP), and di-n-octyl Phthalate (DOP) are synthetic chemicals used as solvent stabilisers and plasticizers in commercial and industrial products. Emerging literature suggests that semi-volatile PAEs (e.g., DEHP) could be toxic to human lung cells, but atmospheric concentration regulations on PAEs remain limited. This work evaluated the individual and combined toxicity of prolonged exposure to environmentally relevant concentrations of DMP, DEP, DEHP, and DOP (10 μM - 1 mM) on Calu-3 human sub-bronchial gland cells. Individual exposure to the tested PAEs yielded the following maximal inhibitory concentration (IC50) at 24 h (4.46 mM DMP, 2.05 mM DEP), 72 h (3.07 mM DMP, 927 μM DEP), and 168 h (418 μM DMP, 106 μM DEP, 343 μM DEHP, 400 μM DOP). Concentration addition and independent action toxicity models predicted synergism and additive effects, respectively, at 72 h exposure with the DMP-DEP combination. Cellular oxygen (O2) consumption was measured via high-resolution respirometry. Exposure of live cells to individual or binary mixtures of PAEs inhibited cellular O2 consumption in a concentration specific manner, indicating direct inhibition of mitochondrial respiratory flux. The results of this work raise a concern on potential long-term adverse effects of atmospheric levels of DMP, DEP, and DOP on the human respiratory system. To the best of our knowledge, this is the first report on the cytotoxic effects of prolonged exposure to DMP, DEP, and DOP and the first to assess the toxicity of binary mixtures of DMP-DEP and DEHP-DOP in a human lung cell line. The results also raise a concern about whether current workroom air quality regulations set to a maximum of 5 mg/m3 on DMP, DEP, and DEHP are safe for human health.

Recycling of sewage sludge and the endogenous phosphorus (P) is a promising strategy for sustainable development, while the disposal of heavy metals (HMs) in sewage sludge and the recovery of targeted P species remain challenges. An innovative method coupling electrokinetic treatment with pyrolysis was proposed in the present study to achieve the effective reclamation of available P and the separation of HMs from sewage sludge. The pristine and FeCl3-assisted electrokinetic treatment were employed for the removal of HMs from sewage sludge and to modify the P species, and the subsequent pyrolysis (300-700 °C) was conducted for the recovery of available P along with the production of biochar. The X-ray absorption near-edge spectroscopy (XANES), 31P liquid nuclear magnetic resonance (NMR) spectroscopy, and sequential chemical extraction were used to systematically determine the evolution of P during the combined treatment of sewage sludge. 19.69-24.80 % of Ni, Cu, and Zn were removed from sewage sludge after pristine electrokinetic treatment, and the HM removal efficiency was further elevated to 47.01-56.86 % with the assistance of FeCl3. Consequently, in comparison with the raw sewage sludge-derived biochars (SBs), the biochars derived from FeCl3-assisted electrokinetic treated sewage sludge (FESBs) contained much lower HM contents and showed higher stability of HMs. The FeCl3-assisted electrokinetic treatment converted alkaline biochars dominated by poorly soluble Ca-phosphates into neutral to slightly acidic biochars dominated by Al/Fe-associated phosphates. This transformation greatly improved the available P concentrations determined by diffusive gradients in thin film in FESBs by 0.6-1.3 folds compared to untreated SBs. Therefore, coupling FeCl3-assisted electrokinetic treatment with pyrolysis could be a promising strategy to achieve the reclamation of available P and the separation of HMs from sewage sludge.

Microplastics (MPs) in terrestrial environments are an emerging contaminant of high concern to ecosystems and human health. However, our understanding of the MPs' fate, particularly their transport within soils, remains elusive. This knowledge gap arises from the multiplicity of coupled physical, chemical and biological processes and parameters affecting MPs transport, together with the scarcity of systematic studies that aim to isolate their individual effects. In this paper, we provide a critical review of the state-of-the-art in our understanding of MPs transport, highlight knowledge gaps and suggest future research to bridge them. We classify the governing factors into four main categories: (i) MPs properties; (ii) soil physicochemical properties; (iii) hydrological conditions; and (iv) biological activity. Our analysis reveals that lack of clear trends in the dependence between MP transport and individual key parameters-often leading to contradictory findings-could be explained by the interference ("co-effects") with other parameters and processes.

Microplastics (MPs) pose a substantial threat to humans and ecosystems. How MPs move in soils is controlled by a large number of coupled parameters, including MPs and soil properties as well as hydrological and geochemical conditions. We conduct laboratory experiments where two commonly MPs types found in soils-polyethylene terephthalate (PET) and polypropylene (PP)-are leached into an idealized soil analog (glass beads). We use time-lapse imaging to analyze the water flow pathways and spectroscopy to measure the MPs transport. We find that MPs impede water infiltration into preferential pathways, with a stronger effect for the more hydrophobic PP, and that PET is more mobile than PP. We explain this by the stronger impedance of PP on water flow that carries the MPs (the driving force), as well as PP surface charge enhancing its adsorption onto soil particles, and its lower density that limits downward transport. These findings advance our understanding the mechanisms underlying MP transport in soils.

The widespread occurrence of new and emerging and persistent organic pollutants (NEPs and POPs) in surface water poses a risk to drinking water supply and consequently human health. The aim of this work was to investigate the occurrence and potential transport of 42 target NEPs and POPs (including per-and polyfluoroalkyl substances (PFAS), pharmaceuticals, pesticides and bisphenols) along the rural and urban environments of three rivers in England. The type and concentrations of pollutants varied between the sampling days and points. Two pharmaceuticals (diclofenac and ibuprofen), two pesticides (diethyl-meta-toluamide (DEET) and prosulfocarb) and a range of PFAS were detected above the method detection limit. The observed PFAS include restricted perfluorooctanoic acid (PFOA), and perfluorooctanesulfonic acid (PFOS) and a newer generation substitute 6:2 fluorotelomer sulfonate (6:2 FTS). The levels of PFOS and diclofenac observed in all studied rivers exceeded the European environmental quality standard (EQS). PFOS and diclofenac high detection frequency in the river Ouse suggests their persistence and potential to contaminate connecting tributaries. An assessment of the ecological risk of prosulfocarb levels in the samples from river Ouse, using the risk quotient method, showed a potential risk to algae, planktonic crustaceans, and fish. Our results suggest that the presence of 12 NEPs and POPs, could potentially be influenced by anthropogenic activities across urban and rural environments of the studied rivers. The study highlights the need for continuous monitoring of restricted and new-generation chemicals in the surface waters to understand their impact on the ecosystem and public health.

Mulch films support crop growth and food security by conserving resources, yet spent films contribute to microplastic pollution, posing disposal challenges. Pyrolysis offers a promising way to recycle these films, often mixed with soil and organic residues. This study explores thermal and catalytic pyrolysis of spent mulch films (over HZSM-5 zeolite), to assess reaction kinetics and product distribution. Characterization of fresh and spent films showed minor physical degradation and slight oxidation in the latter. Thermogravimetric analysis revealed similar thermal degradation patterns for both film types, though HZSM-5 reduced the peak temperature by 40-60 degrees C, with a more marked reduction in the mass loss rate for spent films. Kinetic analysis using a single-step model indicated that HZSM-5 lowered the activation energy from 144.5 kJ mol-1 to 89.8 kJ mol-1, underscoring its catalytic effect. Mulch film pyrolysis can be described by the Avrami model. Thermal pyrolysis generated ethene, propene, and liquid hydrocarbons with a wide carbon number range. In-situ catalytic pyrolysis enhanced gas yields rich in propane and propene, while ex-situ pyrolysis promoted H2, C1-C3 hydrocarbons in the gas phase and naphthalenes in the condensed phase. The large number of hydrocarbons in the liquid phase reflected the roles of free radical and carbenium ion mechanisms (especially in in-situ pyrolysis), while polyaromatic hydrocarbons resulted from the catalyst's Br & Oslash;nsted acidic sites and high temperatures. Contaminants in spent films affected catalyst efficiency, suggesting a need for optimizing pyrolysis conditions. These findings provide insights into catalytic pyrolysis for sustainable mulch film recycling.

Introduction Poly- and perfluoro alkyl substances (PFASs), also known as “forever chemicals”, are persistent in the environment and are challenging to eliminate. There is a growing concern over their widespread presence in the environment and potential adverse effects on human health and ecosystems. Most of the current studies on PFAS pollution are related to aqueous and soil matrices while less emphasis has been given to their relevance to air quality. Several recent studies reported presence of PFASs in atmosphere; however, their atmospheric sources, especially for restricted for more than a decade perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), are not well understood (e.g. Kourtchev et al., 2022; Zhou et al., 2021). Wastewater treatment (WWT) plants are repositories of 1000s of pollutants including PFASs (Barisci & Suri, 2021). Aerosolisation/volatilisation during WWT processes (e.g., aeration, trickling filtration) is suggested as one of the potential sources of PFASs in the atmosphere. However, to the best of our knowledge, aerosolisation potential of PFASs was conducted on a very small number of molecules from that class and under relevant to other than WWT processes conditions e.g., seaspray. The aim of this work is to investigate, for the first time, the aerosolisation potential of the extensive number of PFASs from contaminated waters under relevant to WWT plant conditions.Method and resultsAerosolisation potential of PFASs, covering short-, medium- and long-chain compounds and including legacy PFOA, PFOS and perfluorononanoic acid (PFNA), was examined by aerating PFAS-fortified aqueous solutions at relevant to wastewater effluent concentrations and pHs in an aeration chamber. The generated PFAS-enriched aerosol was collected onto a prebaked glass fiber filter and methanolic solution using a filter pack, and an impinger. The samples were extracted and analysed using an on-line solid phase extraction (SPE) liquid chromatography (LC)-Orbitrap-Mass spectrometry (MS). The PFAS decay from the fortified aqueous solutions were also monitored to understand the extent of PFAS partitioning onto aerosol.Our study indicates that a significant fraction of PFASs can be aerosolised from the contaminated water. This effect was more pronounced for long-chain PFASs irrespective of the pH of the contaminated water. Perfluorocarboxylic acids showed an increase in aerosol phase enrichment with increasing carbon chain length. Short chain PFASs showed lowest aerosol phase enrichment and losses from the contaminated water.ConclusionsThis study, for the first time, establishes the liquid-to-air transfer potential of 15 persistent semi-volatile PFASs including new generation replacements for legacy PFASs such as 4:2 fluorotelomer sulfonate (4:2 FTS) and 8:2 fluorotelomer sulfonate (8:2 FTS) via aerosolisation. The aerosolisation tendency of PFASs was found to increase with increasing carbon chain length. Legacy PFOS and PFOA were detected in the aerosol phase at alarming concentrations suggesting that the contaminated with PFAS waters exposed to aeration can be responsible for observation of “forever chemicals” in the atmosphere. Reference: Barisci and Suri, Water Sci.Technol., 84(12), 3442-3468. https://doi.org/10.2166/wst.2021.484Kourtchev et al. Sci. Total Environ., 835, 155496. https://doi.org/10.1016/j.scitotenv.2022.155496Zhou et al. Environ.Sci.: Processes Impacts, 23(4), 580-587. https://doi.org/10.1039/D0EM00497A

Environmental pollution with per- and polyfluoroalkyl substances (PFAS), commonly referred to as “forever chemicals”, received significant attention due to their environmental persistence and bioaccumulation tendencies. Effluents from wastewater treatment plants (WWTPs) have been reported to contain significant levels of PFAS. Wastewater treatment processes such as aeration have the potential to transfer PFAS into the atmosphere. However, understanding their fate during sewage treatment remains challenging. This study aims to assess aerosolisation of PFAS during a WWTP process. Special emphasis is given to new-generation and legacy PFAS (e.g. perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA)) as they are still observed in sewage after years of restrictions. Particulate matter with aerodynamic diameter ≤10 µm (PM10) collected above a scaled-down activated sludge tank treating domestic sewage for a population of >10 000 people in the UK was analysed for a range of short-, medium-, and long-chain PFAS. Eight PFAS including perfluorobutanoic acid (PFBA), perfluorobutanesulfonic acid (PFBS), perfluoroheptanoic acid (PFHpA), perfluorohexanesulfonic acid (PFHxS), PFOA, perfluorononanoic acid (PFNA), PFOS, and perfluorodecanoic acid (PFDA) were detected in the PM10. The presence of legacy PFOA and PFOS in the PM10 samples, despite being restricted for over a decade, raises concerns about their movement through domestic and industrial sewage cycles. The total PFAS concentrations in PM10 were 15.49 and 4.25 pg m−3 during autumn and spring campaigns, respectively. PFBA was the most abundant of the PFAS, suggesting a shift towards short-chain PFAS use. Our results suggest that wastewater treatment (WWT) processes such as activated sludge aeration could aerosolise PFAS into airborne PM.

The production and consumption of disposable face masks (DFMs) increased intensely during the COVID-19 pandemic, leading to a high amount of them being found in the terrestrial and aquatic environment. The main goal of this research study is to conduct a comparative evaluation of the water-leachability of microplastics (MPs) and chemical additives from various types of disposable surgical/medical face masks (MM DFMs) and filtering face pieces (FFPs). Fourier-Transform Infrared Spectroscopy was used for MPs analysis. Liquid Chromatography/High Resolution Mass Spectrometry was used to analyse analytes presented in the water-leachates of DFMs. FFPs released 3–4 times more microplastic particles compared to MM DFMs. The release of MPs into water from all tested DFMs without mechanical stress suggests potential MP contamination originating from the DFM production process. Our study for the first time identified bisphenol B (0.25–0.42 μg/L) and 1,4-bis(2-ethylhexyl) sulfosuccinate (163.9–115.0 μg/L) as leachables from MM DFMs. MPs in the water-leachates vary in size, with predominant particles <100 μm, and the release order from DFMs is MMIIR > MMII > FFP3>FFP2>MMI. The main type of microplastics identified in the water leachates of the investigated face masks was polypropylene, accounting for 93–97% for MM DFMs and 82–83% for FFPs. Other polymers such as polyethylene, polycarbonate, polyester/polyethylene terephthalate, polyamide/Nylon, polyvinylchloride, and ethylene-propylene copolymer were also identified, but in smaller amounts. FFPs released a wider variety and a higher percentage (17–18%) of other polymers compared to MM DFMs (3–7%). Fragments and fibres were identified in all water-leachate samples, and fragments, particularly debris of polypropylene fibres, were the most common MP morphotype. The findings in this study are important in contributing additional data to develop science-based policy recommendations on the health and environmental impacts of MPs and associated chemical additives originated from DFMs.

Phthalates or phthalic acid esters (PAE) and bis(2-ethylhexyl)adipate (DEHA) are ubiquitous chemicals often used as plasticisers and additives in many industrial products and are classified as both persistent organic pollutants (POPs) and new emerging pollutants (NEPs). Exposure to these chemicals, especially through inhalation, is linked to a wide range of negative health effects, including endocrine disruption. Air particulate matter (PM) with an aerodynamic diameter ≤ 2.5 μm can be enriched with PAEs and DEHA and if inhaled can cause multi-system human toxicity. Therefore, proper monitoring of PAEs and DEHA in PM is required to assess human exposure to these pollutants. In this work, we developed and validated a new and sensitive gas-chromatography high-resolution mass spectrometry (GC-HRMS) method for targeted analysis of PAEs including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), bis(2-ethylhexyl)adipate (DEHA), bis(2-ethylhexyl)phthalate (DEHP), di-n-octyl phthalate (DOP), in PM. Analytical aspects including sample preparation steps and GC-HRMS parameters, e.g., quadrupole isolation window, to enhance method sensitivity have been assessed. The estimated limit of detection (LODs) of target PAEs and DEHA ranged from 5.5 to 17 pg μL-1, allowing their trace-level detection in PM. Extraction efficiencies of 78-101% were obtained for the target compounds. Low DMP and DEP extraction efficiencies from the spiked filter substrates indicated that significant losses of higher volatility PAEs can occur during the sample collection when filter-based techniques are used. This work is the first targeted method based on GC-Orbitrap MS for PAEs and DEHA in environmental samples. The validated method was successfully applied for the targeted analysis of PAEs and DEHA in PM2.5 samples from the eighth most populous city in Brazil, Curitiba. This work is the first to report DBP, DEHA, DEHP, and DOP in urban PM from Brazil. The observed concentrations of PAEs (up to 29 ng m-3) in PM2.5 from Curitiba may not represent the extent of pollution by these toxic compounds since the analysed samples were collected during a COVID-19 restriction when anthropogenic activities were reduced.

Environmental pollution by per- and polyfluoroalkyl substances (PFAS), commonly known as “forever chemicals”, is a major concern. Numerous studies have identified PFAS in various environmental matrices including groundwater, surface water, sea, soil, and atmosphere. Nevertheless, the atmospheric presence of PFAS remains an underexplored area. The exact sources of PFAS in the atmosphere and the mechanisms governing their transfer remain largely elusive. In this study, we investigated, for the first time, the influence of aeration on the aqueous-to-air transfer, of a range of short-, medium-, and long-chain PFAS from aqueous solutions contaminated with PFAS at concentrations and pHs relevant to those at industrial wastewater treatment. PFAS enriched aerosols were generated from the aqueous solutions under three tested pH conditions which were found to affect the partitioning of the individual PFAS. The extent of PFAS aerosolisation also showed a clear dependence on the analyte’s carbon chain length and functional groups. Specifically, the propensity for partitioning into aerosols increased with increasing PFAS carbon chain length. Notably, perfluorosulfonic acids (PFSA) demonstrated a greater potential for aerosolisation compared to perfluorocarboxylic acids (PFCA). Legacy PFAS including perfluorooctanoic acid (PFOA) and perfluorosulfonic acid (PFOS) and a new generation replacement PFAS 8:2 Fluorotelomer sulfonate (8:2 FTS) showed a significant transfer to aerosols from the aqueous solutions. Our results suggest that processes involving aeration of contaminated water (including those at industry) with PFAS could potentially act as a source of atmospheric PFAS.