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To explore the multicenter characteristics of endocrine-like phthalate esters (PAEs) in household dust and propose effective control strategies for global indoor public health. An on-site observational investigation was conducted in nine Chinese cities from 2018 to 2019. A total of 246 household dust samples were collected and analyzed for ten PAE congeners using Gas Chromatography-Mass Spectrometry (GC-MS). Questionnaires were used to gather information on building conditions, indoor behaviors, and ventilation habits. In residential dust from the nine cities, the total concentrations of the ten PAE congeners (∑PAEs) ranged from 0.921 to 29097.297 µg/g. Dicyclohexyl phthalate (DCHP) and di (2-ethylhexyl) phthalate (DEHP) were the dominant congeners in ∑PAEs. Childhood exposure to PAEs through dust ingestion was four orders of magnitude higher than through inhalation, with a carcinogenic risk of 5.47 × 10⁻⁶ for DEHP exposure in household dust. Higher ∑PAEs concentrations were associated with higher temperature, double glazing, wall paint usage, television and computer use, and indoor plant growth. This multicenter on-site investigation confirmed PAE pollution characteristics and uncovered the inacceptable risk of daily DEHP exposure in household dust under real living conditions. Effective mitigation measures based on household-related information, residential characteristics, decoration materials, and lifestyle should be taken to build a healthy household environment.

Polyurethane foam (PUF) is widely used for active air sampling (AAS) of gaseous semivolatile organic compounds (SVOCs). PUF efficiently collects SVOCs with moderate to low volatility, but applications are limited for the more volatile SVOCs due to breakthrough from the PUF trap. The collection efficiency can be predicted by frontal chromatography theory with knowledge of several parameters: the sampled air volume, the breakthrough volume which depends on the PUF/air partition ratio (K_PA), and the number of theoretical plates (N) in the PUF trap. Here we evaluate data from two Canadian air monitoring programs in which front and back PUF traps (P1 and P2) were used to check for breakthrough, as indicated by the back/front ratio (P2/P1) of collected SVOCs. A frontal chromatography model was used to relate collection efficiency of hexachlorobenzene (HCB) and α-hexachlorocyclohexane (α-HCH) to their observed P2/P1 ratios under assumed scenarios of K_PA and N, and apparent N-values for the PUF traps were derived. Results were applied to correcting observed air concentrations of HCB for breakthrough loss. The choice of K_PA greatly influenced the adjusted air concentrations and their variation with temperature.

Background: Large quantities of persistent organic pollutants (POPs) and other persistent, bioaccumulative and toxic substances (PBTs) like heavy metals have accumulated mainly over the last century in reservoirs, such as landfills, dump sites, contaminated sites, and mine tailings, as well as in environmental sinks like soils and sediments. Large floods in the past 20 years have demonstrated the mobilisation of POPs/PBTs from these reservoirs, underscoring the limitations of conventional technical safeguard measures like leachate and wastewater treatment or containment systems at landfills.

Results: This study emphasises the need to develop inventories of POPs/PBTs in these reservoirs for the assessment of future risk of increased flooding triggered by climate change and for priority setting of remediation and securing measures. Further, sea-level rise should be included in these assessments as long-term risk for large areas that are likely to be permanently flooded in the coming decades and centuries. In addition, the risk of release of POPs and other PBTs by industries affected by Natural Hazards Triggering Technological Accidents (Natech) should be globally evaluated. The review emphasises the importance of conducting systematic assessments and inventories to understand the risk of these reservoirs for environmental pollution and human exposure. The releases and remobilisation of POPs/PBTs can lead to higher levels in food and drinking water with increased human exposure. In addition to fish, it is crucial to consider livestock grazing in flood plains and other areas affected by floods, and to include them in inventories and risk management.

Conclusion: Based on these assessments, appropriate measures must be developed to eliminate or secure the respective reservoirs, following the precautionary approach. Whilst management measures have been initiated in affected areas (including affected feed/biomass), such as floodplains, there is a need to develop them more systematically. This review advocates for a comprehensive and precautionary approach to address the environmental challenges posed by climate change for POPs and other PBTs reservoirs, with an emphasis on increased flooding and sea-level rise. The substitution of POPs/PBTs in non-essential uses should be implemented to reduce future risks. A synergistic implementation of the Stockholm, Minimata, and Climate Convention can be used as frame for inventories and mitigation.

Examining boiler failure causes is crucial for thermal power plant safety and profitability. However, traditional approaches are complex and expensive, lacking precise operational insights. Although data-driven approaches hold substantial potential in addressing these challenges, there is a gap in systematic approaches for investigating failure root causes with unlabeled data. Therefore, we proffered a novel framework rooted in data mining methodologies to probe the accountable operational variables for boiler failures. The primary objective was to furnish precise guidance for future operations to proactively prevent similar failures. The framework was centered on two data mining approaches, Principal Component Analysis (PCA) + K-means and Deep Embedded Clustering (DEC), with PCA + K-means serving as the baseline against which the performance of DEC was evaluated. To demonstrate the framework’s specifics, a case study was performed using datasets obtained from a waste-to-energy plant in Sweden. The results showed the following: (1) The clustering outcomes of DEC consistently surpass those of PCA + K-means across nearly every dimension. (2) The operational temperature variables T-BSH3rm, T-BSH2l, T-BSH3r, T-BSH1l, T-SbSH3, and T-BSH1r emerged as the most significant contributors to the failures. It is advisable to maintain the operational levels of T-BSH3rm, T-BSH2l, T-BSH3r, T-BSH1l, T-SbSH3, and T-BSH1r around 527 °C, 432 °C, 482 °C, 338 °C, 313 °C, and 343 °C respectively. Moreover, it is crucial to prevent these values from reaching or exceeding 594 °C, 471 °C, 537 °C, 355 °C, 340 °C, and 359 °C for prolonged durations. The findings offer the opportunity to improve future operational conditions, thereby extending the overall service life of the boiler. Consequently, operators can address faulty tubes during scheduled annual maintenance without encountering failures and disrupting production.

Halomethoxybenzenes (HMBs) and related halomethoxyphenols are produced naturally in the marine and terrestrial environment and some also have anthropogenic origins. They are relatively volatile and water soluble and undergo atmospheric exchange with water bodies and soil. Here we report air-surface exchange of HMB compounds brominated anisoles and chlorinated dimethoxybenzenes in a Subarctic lake and catchment in Sweden during September 2022. HMBs were isolated from water on solid-phase extraction cartridges and from ground litter/soil by solvent extraction and determined by capillary gas chromatography - quadrupole mass spectrometry. Identified compounds in lake and stream water in the 10–100 pg L⁻¹ range were 1,2,4,5-tetrachloro-3,6-dimethoxybenzene (DAME) > 2,4-dibromoanisole (DiBA) ≥ 2,4,6-tribromoanisole (TriBA) > 1,2,3,4-tetrachloro-5,6-dimethoxybenzene (tetrachloroveratrole, TeCV). DAME and the related compound 2,3,5,6-tetrachloro-4-methoxyphenol (DA) are reported in Subarctic litter/soil in the range 0.005–1.1 mg kg⁻¹ dry weight (dw), whereas DiBA and TriBA were not detected in any litter/soil sample and TeCV in only one. Exchanges were assessed from concentrations in water and soil, air concentrations from a monitoring station at Pallas, Finland, and the physicochemical properties of the HMBs. Fluxes to and from the lake were estimated using the two-film gas exchange model. Net loadings (deposition minus volatilization) for the month of September were − 23, −15 and − 68 g for DiBA, TriBA and DAME, respectively, which amounted to about 4–7 % of the estimated lake inventory. An exchange assessment for DAME from litter/soil showed significant net volatilization at five sites, net deposition at one site and near-equilibrium at one site. The Torneträsk catchment appeared close to steady state with respect to HMB exchange during September 2022. The situation could be different during the warmer and colder seasons, and extending the study to cover these periods is a suggested next step.

Polycyclic aromatic hydrocarbons (PAHs), released from petrogenic, pyrogenic or diagenetic sources (degradation of wood materials), are of global concern due to their adverse effects, and potential for long-range transport. While dissolved PAHs have been frequently reported in the literature, there has been no consistent approach of sampling across water bodies. Passive samplers from the AQUA/GAPS-MONET initiative were deployed at 46 sites (28 marine and 18 freshwater), and analyzed for 28 PAHs and six polycyclic musks (PCMs) centrally. Freely dissolved PAH concentrations were dominated by phenanthrene (mean concentration 1500 pg L^-1; median 530 pg L^-1) and other low molecular weight compounds. Greatest concentrations of phenanthrene, fluoranthene, and pyrene were typically from the same sites, mostly in Europe and North America. Of the PCMs, only galaxolide (72% of samples) and tonalide (61%) were regularly detected, and were significantly cross-correlated. Benchmarking of PAHs relative to penta- and hexachlorobenzene confirmed that the most remote sites (Arctic, Antarctic, and mountain lakes) displayed below average PAH concentrations. Concentrations of 11 of 28 PAHs, galaxolide and tonalide were positively correlated (P < 0.05) with population density within a radius of 5 km of the sampling site. Characteristic PAH ratios gave conflicting results, likely reflecting multiple PAH sources and postemission changes.

Arctic melting is an effect of climate change; the use of fossil fuels in marine shipping emits large amounts of air emissions that impact climate change, and Arctic aquatic and human life. Swedish pulp and paper mills generate large amounts of waste and side streams that could be utilized. The production of forest-based biofuel may be a promising solution to achieve sustainable Arctic marine shipping. This review highlights the socio-economic impacts associated with the production of forest-based biofuel in Sweden, the related opportunities, challenges, knowledge gaps, and further need of research. From the economic perspective, it was found that the production and use of forest-based biofuel have short and long-term economic sustainability benefits: (a) short-term benefits, the use of the waste and side streams of the pulp and paper industry is a low-cost available feedstock, unlike first-generation biofuel from crops like corn forest-based biofuels neither require additional land use, water resources nor compete with food. (b) Long-term benefits: (i) the Swedish shipping sector depends on imported fossil fuels, these new biofuels can replace partly those imported fossil fuels that will reduce shipping costs, and generate economic benefits for local consumers. (ii) Usage of forest-based biofuels as blends with conventional fuels in existing engines will reduce greenhouse gas emissions from the Arctic shipping to the set limits in the region. (iii) One of the important socio-economic impacts of forest-based biofuel production and use is the new job creation and employment opportunities that will impact the local communities and livelihoods of indigenous people in the area. From a societal perspective, stakeholder involvement is essential to address the sustainability challenges of biofuel production: EU policymakers need to encourage the production and use of biofuels by developing policies that promote biofuel use. Further studies are needed to develop more efficient and low-cost biofuel production routes, more investments in related research and development are required as well. Local indigenous communities must be involved in the decision-making process through surveys, local dialogues, and research studies. The production of forest-based biofuels has great potential and many social-economic impacts alongside the environmental benefits.

Soil attributes and their environmental drivers exhibit different patterns in different geographical directions, along with distinct regional characteristics, which may have important effects on substance migration and transformation such as organic matter and soil elements or the environmental impacts of pollutants. Therefore, regional soil characteristics should be considered in the process of regionalization for environmental management. However, no comprehensive evaluation or systematic classification of the natural soil environment has been established for China. Here, we established an index system for natural soil environmental regionalization (NSER) by combining literature data obtained based on bibliometrics with the analytic hierarchy process (AHP). Based on the index system, we collected spatial distribution data for 14 indexes at the national scale. In addition, three clustering algorithms—self-organizing feature mapping (SOFM), fuzzy c-means (FCM) and k-means (KM)—were used to classify and define the natural soil environment. We imported four cluster validity indexes (CVI) to evaluate different models: Davies-Bouldin index (DB), Silhouette index (Sil) and Calinski-Harabasz index (CH) for FCM and KM, clustering quality index (CQI) for SOFM. Analysis and comparison of the results showed that when the number of clusters was 13, the FCM clustering algorithm achieved the optimal clustering results (DB = 1.16, Sil = 0.78, CH = 6.77 × 106), allowing the natural soil environment of China to be divided into 12 regions with distinct characteristics. Our study provides a set of comprehensive scientific research methods for regionalization research based on spatial data, it has important reference value for improving soil environmental management based on local conditions in China.

Fungi and substrates undergoing fungal decomposition were collected from forests in northern and southernSweden and analyzed for chlorinated dimethoxybenzenes (DMBs). Specimens were fungi fruiting bodies, rottingwood, forest litter and underlying humus. Targeted compounds were DAME (1,2,4,5-tetrachloro-3,6-DMB) andrelated fungal secondary metabolites. A screening procedure was developed which involved soaking the speci-mens in ethyl acetate followed by analysis by capillary gas chromatography – mass spectrometry with mass selec-tive detection (GC-MSD). DAME was the most frequently found (62% of 47 specimens) and often the most abun-dant target compound, with range and mean ± SD concentrations of <0.0017–3.81 and 0.21 ± 0.63 mg kg−1ww. Based on log-log correlations of partition coefficients of hydrophobic compounds between fungal biomass/water (KD) and octanol/water (KOW), five species of fungi are suggested to produce DAME de novo versus bioaccu-mulation from forest runoff water. Full-scan mass spectra of some high-concentration specimens indicated thepresence of a Cl2DMB and a Cl3DMB, which could not be identified further due to lack of standards, anddrosophilin A (DA = 2,3,5,6-tetrachloro-4-methoxyphenol), the precursor to DAME. Tetrachloroveratrole(TeCV = 1,2,3,4-tetrachloro-5,6-DMB) was found in only a few specimens. This study supports our hypothesis offungi as a source of DAME in terrestrial runoff and indicates that other chlorinated secondary metabolites arepresent. DAME is widely distributed globally, and it would be good to have a better understanding of its sourcesand pathways as a marker of terrestrial organochlorines and their availability for bioaccumulation

Climate change is expected to alter global temperature and precipitation patterns resulting in complex environmental impacts. The proposed higher precipitation in northern Scandinavia would increase runoff from land, hence increase the inflow of terrestrial dissolved organic matter (tDOM) in coastal regions. This could promote heterotrophic bacterial production and shift the food web structure, by favoring the microbial food web. The altered climate is also expected to affect transport and availability of organic micropollutants (MPs), with downstream effects on exposure and accumulation in biota. This study aimed to assess climate-induced changes in a Bothnian Sea food web structure as well as bioaccumulation patterns of MPs. We performed a mesocosms-study, focusing on aquatic food webs with fish as top predator. Alongside increased temperature, mesocosm treatments included tDOM and MP addition. The tDOM addition affected nutrient availability and boosted both phytoplankton and heterotrophic bacteria in our fairly shallow mesocosms. The increased tDOM further benefitted flagellates, ciliates and mesozooplankton, while the temperature increase and MP addition had minor effect on those organism groups. Temperature, on the other hand, had a negative impact on fish growth and survival, whereas tDOM and MP addition only had minor impact on fish. Moreover, there were indications that bioaccumulation of MPs in fish either increased with tDOM addition or decreased at higher temperatures. If there was an impact on bioaccumulation, moderately lipophilic MPs (log Kow 3.6 - 4.6) were generally affected by tDOM addition and more lipophilic MPs (log Kow 3.8 to 6.4) were generally affected by increased temperature. This study suggest that both increased temperatures and addition of tDOM likely will affect bioaccumulation patterns of MPs in shallow coastal regions, albeit with counteracting effects.