Probabilistic ecological risk characterizing and source-specific risk apportionment of antibiotics in rivers in the sub-center of Beijing, China.

The widespread occurrence of antibiotics in urban rivers has raised global concerns for ecological security. Quantitative source-specific risk apportionment of antibiotics is crucial for targeted and effective ecological risk management, but is rarely studied. In this study, a source-specific ecological risk apportionment model for antibiotics was developed by combining the ecological risk quotient (RQ) method and the positive matrix factorization (PMF) model.

[Research Progress on Adsorption, Migration, and Compound Toxicity of Microplastics and Antibiotics in Soil].

Microplastics and antibiotics are two typical emerging environmental pollutants that are widely present in soil and pose a threat to the health of soil ecosystems. Microplastics can act as carriers, adsorbing antibiotics and influencing their migration behavior. This can result in complex contamination, causing unpredictable impacts or even hazards to the soil ecosystem.

Single and Combined Effects of Aged Polyethylene Microplastics and Cadmium on Nitrogen Species in Stormwater Filtration Systems: Perspectives from Treatment Efficiency, Key Microbial Communities, and Nitrogen Cycling Functional Genes.

Microplastics and heavy metal contamination frequently co-occur in stormwater filtration systems, where their interactions may potentially compromise nitrogen removal. Current research on microplastics and Cd contamination predominantly focuses on soils and constructed wetlands, with limited attention given to stormwater filtration systems. In this study, the single and synergistic effects of aged polyethylene microplastics (PE) and cadmium (Cd) contamination in stormwater infiltration systems were investigated from perspectives of nitrogen removal, microbial community structures, and predicted functional genes in nitrogen cycling.

[Research Progress on Plastic Aging Processes and Their Environmental Hazards].

Plastic pollution has become a global environmental issue, posing notable threats to ecosystems and human health. Plastic aging is a continuous dynamic process, during which plastics of various sizes are produced and exist, such as large plastics, microplastics, and nanoplastics. Regardless of the size, plastics continuously fragment and release plastic additives and other soluble products.

Particle Size-Dependent Monthly Variation of Pollution Load, Ecological Risk, and Sources of Heavy Metals in Road Dust in Beijing, China.

Road dust carries various contaminants and causes urban non-point source pollution in waterbodies through runoff. Road dust samples were collected in each month in two years and then sieved into five particle size fractions. The concentrations of ten heavy metals (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, Fe) in each fraction were measured.

A nationwide probabilistic risk assessment and a new insight into source-specific risk apportionment of antibiotics in eight typical river basins in China: Human health risk and ecological risk.

China is the largest producer and consumer of antibiotics, a nationwide study on the contamination of antibiotics in China is urgently needed, and source apportionment towards risks associated with antibiotics is now attracting increasing attention. In this study, based on eight antibiotics at 666 sampling sites, spatial variations and probabilistic risks (human health and ecological risk) of antibiotics in eight river basins in China were analyzed. Source-specific health and ecological risk associated with antibiotics in a typical basin was apportioned quantitatively.

Distribution characteristics and relationship of microplastics, phthalate esters, and bisphenol A in the Beiyun River basin of Beijing.

Urban rivers are closely related to human life, and due to the widespread use of plastic products, rivers have become important carriers of pollutants such as microplastics (MP), phthalate esters (PAEs), and bisphenol A (BPA). However, our understanding of the distribution characteristics and relationships of MP, PAEs, and BPA in rivers is limited. In this study, MP, six PAEs and BPA were detected in the water and sediments of the Beiyun River basin.

Antibiotic intermediates and antibiotics synergistically promote the development of multiple antibiotic resistance in antibiotic production wastewater.

Antibiotic resistance (AR) is a major public health concern. Antibiotic intermediates (AIs) used in the production of semisynthetic antibiotics have the same bioactive structure as parent antibiotics and synthetic antibiotic production wastewater usually contains high concentrations of residual AIs; however, the effects of AIs and their interactive effects with antibiotics on the emergence of AR are unknown. In this study, antibiotic-sensitive E.

[Research Progress on Production and Emission of CH and NO from Urban Rivers].

Methane （CH） and nitrous oxide （NO） are concerning greenhouse gases. Urban rivers have been important emission sources of CH and NO in recent years. It is meaningful for city greenhouse gas reduction to provide a systematic analysis of spatiotemporal characteristics, mechanisms, and influencing factors of the production and emission of CH and NO from urban rivers.

The difference between tire wear particles and polyethylene microplastics in stormwater filtration systems: Perspectives from aging process, conventional pollutants removal and microbial communities.

Tire wear particles (TWPs) in stormwater runoff have been widely detected and were generally classified into microplastics (MPs). TWPs and conventional MPs can be intercepted and accumulated in stormwater filtration systems, but their impacts on filtration, adsorption and microbial degradation processes of conventional pollutants (organic matters, nitrate and ammonium) have not been clarified. TWPs are different from MPs in surface feature, chemical components, adsorption ability and leaching of additives, which might lead to their different impacts on conventional pollutants removal.

Exploring polystyrene weathering behavior: From surface traits to micro(nano)plastics and additives release.

Plastic weathering in the natural environment is a dynamic and complex process, where the release of microplastics, nanoplastics and additives poses potential threats to ecosystems. Understanding the release of different weathering products from plastics is crucial for predicting and assessing the environmental hazards of plastics. This study systematically explored these phenomena by exposing polystyrene (PS) to UV irradiation and mechanical agitation for different durations (1 day, 5 days, 10 days, 20 days).

A combined evaluation of the characteristics and antibiotic resistance induction potential of antibiotic wastewater during the treatment process.

Antibiotic wastewater contains a variety of pollutant stressors that can induce and promote antibiotic resistance (AR) when released into the environment. Although these substances are mostly in concentrations lower than those known to induce AR individually, it is possible that antibiotic wastewater discharge might still promote the AR transmission risk via additive or synergistic effects. However, the comprehensive effect of antibiotic wastewater on AR development has rarely been evaluated, and its treatment efficiency remains unknown.

Enhanced denitrification of the AO-MBBR system used for expressway service area sewage treatment: A new perspective on decentralized wastewater treatment.

Decentralized wastewater treatment warrants considerable development in numerous countries and regions. Owing to the unique characteristics of high ammonia nitrogen concentrations and low carbon/nitrogen ratio, nitrogen removal is a key challenge in treating expressway service area sewage. In this study, an anoxic/oxic-moving bed biofilm reactor (A/O-MBBR) and a traditional A/O bioreactor were continuously operated for 115 days and their outcomes were compared to investigate the enhancement effect of carriers on the total nitrogen removal (TN) for expressway service area sewage.

Naturally aged polylactic acid microplastics stunted pakchoi (Brassica rapa subsp. chinensis) growth with cadmium in soil.

Biodegradable microplastics (BMPs) and cadmium (Cd) are posing threats to agro-systems especially to plants and current studies mostly used virgin BMPs to explore their ecological effects. However, effects of naturally aged BMPs and their combined effects with Cd on pakchoi are yet to be unraveled. Therefore, this study incubated naturally aged polylactic acid (PLA) MPs through soil aging process and investigated the single and combined effects of Cd and PLA MPs (virgin and aged) on pakchoi (Brassica rapa subsp.

Machine-learning-aided application of high-gravity technology to enhance ammonia recovery of fresh waste leachate.

Stripping is widely applied for the removal of ammonia from fresh waste leachate. However, the development of air stripping technology is restricted by the requirements for large-scale equipment and long operation periods. This paper describes a high-gravity technology that improves ammonia stripping from actual fresh waste leachate and a machine learning approach that predicts the stripping performance under different operational parameters.

[Spatial Variation and Potential Sources of Microplastics in Rivers in Tongzhou District, Beijing].

Microplastics are emerging contaminants, which can also absorb other contaminants, threatening the health of river ecosystems. However, research on the pollution of microplastics in rivers in northern China is still lacking. In this study, based on the sampling and analysis of water samples in 19 sites in six rivers in Tongzhou district, Beijing, the composition, spatial variation, and potential sources of microplastics were explored.

Impact of particle sizes on health risks and source-specific health risks for heavy metals in road dust.

To analyze the impact of particle sizes on sources and related health risks for heavy metals, road dust samples in Beijing were collected and sifted into five particle sizes. The positive matrix factorization (PMF), human health risk assessment model (HHRA), and Monte Carlo simulation were used in the health risk assessment and source apportionment. Results showed that mass of particles < 74 μm occupied about 50% of the total particles, while only 8.

[Temporal and Spatial Distribution Characteristics and Source Apportionment of Runoff Pollution in Langfang City].

Urban runoff pollution can carry pollutants into the receiving water through scouring and leaching, causing black color and odor or eutrophication. Understanding and mastering the characteristics of runoff pollution is a prerequisite for the effective control of runoff pollution. This study aimed to comprehensively analyze the temporal and spatial distribution characteristics of runoff pollution and the correlation between pollutants in the urban area of Langfang City.

A four-way model (FEST) for source apportionment: Development, verification, and application.

In studying the spatial, temporal, and particle size variations heavy metal sources, a source apportionment model for a four-way array of data is required. In this study, referencing two-way and three-way models, a four-way (particle fractions, elements, sites, and time) source apportionment model (FEST) was developed. Errors in the three-way models solving four-way problems verified the necessity of developing the FEST model.

Prediction of tempo-spatial patterns and exceedance probabilities of atmospheric corrosion of Q235 carbon steel across China.

To reduce the losses caused by the atmospheric corrosion of carbon steels, it is important to establish a prediction model to determine the corrosion rate of carbon steels in natural environments. In this study, a prediction model of atmospheric corrosion of Q235 carbon steel (PMACC-Q235) in China was established by coupling the mean impact value algorithm and back propagation artificial neural network. Tempo-spatial patterns of corrosion rates in five long-exposure time categories across China were analyzed.

Multiscale spatiotemporal characteristics of landscape patterns, hotspots, and influencing factors for soil erosion.

Soil erosion is an increasingly serious eco-environmental problem, and effective control of soil erosion is an important part of soil resource protection and ecological restoration. In this study, the multi-scale characteristics and influencing factors of soil erosion were analyzed in the Beijing-Tianjin-Hebei (BTH) region from 2000 to 2015. The results showed that the average soil erosion in the study area was 3500 t/(km·a), in which the severe erosion areas accounted for 10% of the total area.

Spatial-temporal characteristics, source-specific variation and uncertainty analysis of health risks associated with heavy metals in road dust in Beijing, China.

Based on the concentrations of ten heavy metals (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, Fe) in 144 road dust samples collected from 36 sites across 4 seasons from 2016 to 2017 in Beijing, this study systematically analyzed the levels and main sources of health risks in terms of their temporal and spatial variations. A combination of receptor models (positive matrix factorization and multilinear engine-2), human health risk assessment models, and Monte Carlo simulations were used to apportion the seasonal variation of the health risks associated with these heavy metals. While non-carcinogenic risks were generally acceptable, Cr and Ni induced cautionary carcinogenic risks (CR) to children (confidence levels was approximately 80% and 95%, respectively).

Temporal variations of levels and sources of health risk associated with heavy metals in road dust in Beijing from May 2016 to April 2018.

To analyze the temporal variations of heavy metals, health risk, and source-specific health risk, 24 road dust samples were collected from Beijing in each month in two years. The temporal variations of Hg, Pb, and Ni were higher than other heavy metals. Most heavy metals reached their highest concentrations either in winter or in spring, then the concentrations decreased and reached the lowest values in autumn.

Source-specific ecological risk analysis and critical source identification of heavy metals in road dust in Beijing, China.

To explore the spatial variation of source-specific ecological risks and identify critical sources of heavy metals in road dust, 36 road dust samples collected in Beijing in March 2017 were analyzed for heavy metals. A new method that takes into consideration the heavy-metal toxic response and is flexible to changes in the number of calculated heavy metals, called the Nemerow integrated risk index (NIRI), was developed for ecological risk assessment. The NIRI indicated that heavy metals posed considerable to high risks at the majority of sites, and 22 % of the sites suffered extreme risk in spring (NIRI > 320).