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Wastewaters are plausible arenas for antibiotic resistance evolution and transmission, yet selection for resistance by municipal wastewater has rarely been empirically demonstrated. Here, we experimentally investigate the potential of untreated municipal wastewater from 47 countries to select for antibiotic resistance and explore possible drivers. Using a functional selection assay with 340 mixed Escherichia coli strains, we find that sterile-filtered samples from 14 countries select significantly for resistance to at least one antibiotic class compared to baseline, while the majority select significantly against resistance. Similar results were generated using natural wastewater communities. Additionally, we report a comprehensive characterization of antibiotics and antibacterial biocides in the wastewaters. None of the 22 analyzed antibiotics could be assigned as key drivers for selection in E. coli, whereas e.g. folate pathway antagonists and macrolides often exceed predicted non-selective concentrations for other bacteria by >10-fold. Despite detecting 13 (out of 20 analyzed) organic antibacterial biocides, their potential for co-selection remains unclear. Measured chemical constituents correlate only weakly with observed selection, suggesting complex mixture effects and/or selection by unmeasured compounds. The clear deselection of resistance by most samples indicates that many resistant strains have impaired fitness in wastewaters with limited antibiotic selection pressure.

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.

We report hydrogeochemical and isotopic observations across the Baltic Sea from two research expeditions: (1) a ~5000 km cruise-track onboard the R/V Skagerak in 2023 and (2) a land-based sampling for terrestrial endmembers in 2024. The ship-based observations include continuous monitoring of hydrographic parameters, pH, and ²²²Rn in surface water. In addition, we collected 542 discrete samples from the water column, vertical profiles (n = 69 stations), and meteorological data. Land observations include discrete samples from beach groundwater (n = 77), nearshore surface water (n = 47), and rivers close to the coastline (n = 46). Discrete samples were analyzed for short-lived radium isotopes, nutrients, dissolved organic and inorganic carbon, total dissolved nitrogen, total alkalinity, methane, and stable isotopes (δ¹⁸OH2O, δ²H_H2O, δ¹³C_DIC, δ¹³C_CO2, δ¹³C_CH4). Data products include seven open-access files. This dataset forms the deposit for upcoming original research publications. This dataset will also be valuable to researchers interested in the hydrogeochemistry of coastal seas, like the Baltic Sea, and more generally interested in submarine groundwater discharge and estuarine biogeochemistry.

Passive sampling (PS) combined with nontargeted analysis provides a time-representative picture of contaminants in water that are not covered by conventional monitoring. This innovative approach was further enhanced by chemical space modeling to predict the chemical space captured by passive samplers. In this study, three passive samplers for polar compounds, i.e., POCIS, hydrogel-based passive sampler (HPS), and Speedisk, were deployed in municipal wastewater treatment plant effluent and analyzed by liquid chromatography–high-resolution mass spectrometry (LC–HRMS) with data-independent acquisition (DIA). Compounds identified by suspect screening were used together with target compounds to map the sampled chemical space using a multivariate analysis of 1686 compounds and 31 physicochemical descriptors. In total, 216 unique compounds were identified, including 127 compounds from suspect screening, of which 61 were not covered by targeted analysis. A similar number of compounds were detected in all three passive samplers, indicating a surprisingly similar sampled chemical space. Using chemical space mapping, a chemical domain of 1150 compounds within the molar mass range of 150–600 was identified to be sampled by PS with 95% confidence. This novel approach emphasizes combining analytical and modeling tools to provide deeper insight into the limitations of passive sampler coverage.

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.

Phthalate esters (PAEs) have been extensively used in the household environment globally for decades, posing persistent hazards. There is significant attention on the characteristics of PAEs in household dust (HD-PAEs) in China, driven by an increasing awareness of their endocrine-disruptor toxicity. In this study, 876 peer-reviewed papers published between 2000 and 2023 were evaluated and screened for raw numerical data of HD-PAEs in residential households, including 27 papers available for final analysis. The national mean concentration of ∑8HD-PAEs was approximately 1002 mg/kg based on calculation of the samples-weighted mean concentration. Pollution levels in several provinces, including Shaanxi, Liaoning, Chongqing, Heilongjiang, Hunan, and Beijing, exceeded the national average by 230 %, 209 %, 151 %, 84.6 %, 54.7 %, and 24.6 %, respectively. Spatial and temporal differences were observed in HD-PAEs pollution, with DEP, DMP and DCHP exhibiting higher concentrations in northern cities (P < 0.050), while DEP and DBP demonstrated higher concentrations in winter (P < 0.050). The two principal sources of HD-PAEs were identified through correlation analysis and principal component analysis: the use of plastic products and decoration materials (DEP, DEHP, DIBP and DMP accounted for 58.6 %), and personal care products (DBP accounted for 21.3 %). DEHP remains the predominant HD-PAEs, despite its concentration decreasing from 2005 to 2020. The carcinogenic risk of DEHP ranged from 2.45 × 10−5 to 2.45 × 10−4, and the non-carcinogenic risk of DEHP in Shaanxi (HI = 1.05), Chongqing (HI = 1.41), and Liaoning (HI = 1.41) exceeded the acceptable levels, with dermal contact and ingestion being the primary exposure routes. Based on these findings, we recommend prioritizing environmentally friendly building materials and minimizing the use of plastic products. Proper ventilation, especially during winter, and regular household cleaning and dust removal should be implemented to enhance environmental protection in homes. These measures can effectively reduce exposure to HD-PAEs and protect the health of residents.

Measuring dissolved concentrations of polybrominated diphenyl ethers (PBDEs) and non-BDE flame retardants on a global scale provides critical insights into the effectiveness of the Stockholm Convention. In the present study, we deployed passive sampling devices at 43 seawater and freshwater sites covering 21 countries from 2016 to 2020. The detection frequencies were 20−94% for BDE congeners and 33−42% for dechlorane plus, higher than those (0−20%) for other target compounds. The median concentrations of dissolved Σ₉PBDE (sum of BDE-28, -47, -66, -85, -99, -100, -153, -154, and -183) were 0.28 and 0.64pg L−1 in seawater and freshwater, respectively. The concentrations of dissolved Σ₉PBDE, along with published data, slightly increased before 2016 and remained steady from 2016 to 2018, indicating delayed effects of the global phase out of technical Penta- and Octa-BDEs. The log-transformed concentrations of individual BDE congeners were better correlated with regional gross domestic product than with population density. The potential ecological risk of BDE-47 was low, and there was a lack of key risk indicators for other compounds. The present study documented the delayed response of the aquatic environment to the regulatory actions on reducing PBDE emissions.

Halomethoxybenzenes (HMBs), including 2,4-dibromoanisole (DBA), 2,4,6-tribromoanisole (TBA), and droso-philin A methyl ether (1,2,4,5-tetrachloro-3,6-dimethoxybenzene; DAME) are bioaccumulative halogenatedcompounds with natural and anthropogenic sources. This study characterized these three HMBs in seawater andDAME in air in the Bering and Chukchi Seas. The goal was to describe and explain distributions of HMBs asseasonal ice retreated in spring. The results show that concentrations of individual HMBs are sensitive to distinctenvironmental processes. DBA decreased during spring blooms, while spring freshwater brought DAME into thesystem. Net volatilization of DAME occurred at a freshwater-influenced site, while all other site samplesdemonstrated net deposition of DAME from the atmosphere to seawater or equilibrium with respect to gas ex-change. The highest concentrations of TBA occurred near freshwater, but there were no statistically significanttrends in the levels of this compound. Arctic sampling did not show evidence of a buildup of HMBs under icefrom possible production by ice algae or bacteria. The different trends in concentrations of individual HMBs andtheir sensitivity to environmental variables over a short timescale complicates comparisons across systems,evaluations of ecological function, and potential risk assessments.

Phthalate esters (PAEs) existed in household environment globally, and household airborne dust PAEs (HD-PAEs) have garnered significant attention due to their endocrine-like toxicity. In on-site study investigating PAE contamination from 60 households across three Chinese cities, we analyzed 43 dust samples for specific PAE components and conducted comprehensive total DNA demethylation potential (TDP) toxicity assays. Ten congeners were detected across all cities (130.26–3683.66 μg/g), with Harbin showing the highest median ∑10PAEs concentration (1970.71 μg/g). Decoration, living habits and housing characteristics, collectively influenced PAE levels, with DEHP and DCHP being the dominant congeners. Correlation and factor analyses identified four primary sources: (1) plastic products and personal care products (DEP, DPP, and DEHP: 36.74 %), (2) adhesive products (DMEP and DHXP: 15.06 %), (3) flooring materials and personal care products (DNOP and DBP: 12.55 %), and (4) packing materials and synthetic leather (BBP: 11.40 %). While non-carcinogenic risks were acceptable (HI < 1), DEHP posed a potential carcinogenic risk (LCR > 10⁻⁶). The TDP assay revealed a 79.07 % positive demethylation, and extensive modeling demonstrated a significant positive correlation between DBP and TDP (p < 0.1). This study provides valuable insights into HD-PAEs pollution and its health risk mechanisms, offering critical evidence for future risk assessments.