Mobile genetic elements (MGEs) play critical roles in transferring antibiotic resistance genes (ARGs) among different microorganisms in the environment. This study aimed to explore the fate of MGEs during chicken manure (CM) and bovine manure (BM) composting to assess horizontal transfer risks of ARGs. The results showed that the removal efficiency of MGEs during CM composting was significantly higher than that during BM composting, because the potential host bacteria of MGEs were eliminated largely during CM composting. Meanwhile, these potential host bacterial communities are significantly influenced by pH, NH4+, NO3− and total N, which can be used to regulate host bacterial communities to remove MGEs during composting. Projection pursuit regression further confirmed that composting can effectively reduce the horizontal transfer risk of ARGs, especially for CM composting. These results identified the critical roles of host bacterial communities in MGEs removal during composting of different animal manures.

Urban heat island (UHI), an iconic consequence of anthropogenic activities and climate condition, affects air pollution, energy use, and health. Therefore, better understanding of the temporal dynamics of UHI is required for sustainable urban planning to mitigate air pollution under a changing climate. Here, we present the evolution of UHI intensity (UHIi) and its controlling factors in the Seoul metropolitan area, Korea, over the last 56 years (1962–2017), which has experienced unique compressed economic growth and urban transformation under monsoon climate. The analysis demonstrated an inverted U-shape long-term variation of UHIi with the progress of urban transformation and economic climate which has not been reported in Asian cities before. Meanwhile, short-term variations in UHIi are related to both diurnal temperature range and duration after rainfall event unlike previous studies, and the UHIi was exacerbated by heat waves. Our findings suggest that the UHIi will exhibit different temporal dynamics with future changes in the monsoon climate, and heat waves in the urban area will be reinforced if current rapid urbanization continues without a shift toward sustainable and equitable development. Asian cities that are likely to face the similar urbanization trajectory and the implications are that urban (re)development strategy considers changes in rainfall magnitude and timing due to monsoon system variation under changing climate and plans to mitigate synergy between heat wave and UHI in this area.

Apportioning sources of environmental pollutants is key to controlling pollution. In this study, the sources of heavy metals to 234 agricultural soils from the Jianghan Plain (JHP) (∼22454 km2) in central China were discriminated between using Cd and Pb isotope compositions and multivariate statistical analyses. Concentrations of some metals in JHP soils (0.48 ± 0.2, 48.2 ± 15.9, 0.12 ± 0.23, 48.8 ± 16.4, 36.5 ± 9.8, and 96.8 ± 42.2 mg kg−1 for Cd, Cu, Hg, Ni, Pb, and Zn, respectively) were higher than background concentrations in Chinese soil. The Cd isotope compositions for the JHP soils (δ114/110Cd values −0.76‰ to −0.25‰) were similar to Cd isotope compositions found for smelter dust and incinerator fly ash, indicating Cd was supplied to the JHP soils by ore smelting and/or refining processes. The Pb isotope compositions for the JHP soils (206Pb/207Pb 1.182–1.195 and 208Pb/206Pb 2.078–2.124) were between the Pb isotope compositions found for Chinese coal and natural sources, which a binary isotope mixing model indicated contributed 52% and 48%, respectively, of the Pb in JHP soils. Cluster analysis and positive matrix factorization indicated that the sources of heavy metals in JHP soils may consist of smelting and/or refining activities, coal combustion, agricultural activities, and natural sources (including Han River sediment and soil parent materials). The isotope fingerprints and multivariate statistical analyses together indicated that coal combustion and smelting and/or refining activities were the main anthropogenic sources of heavy metals polluting JHP soils.

Unplanned oil spills during offshore oil production are a serious problem for the industry and the marine environment. Here we assess the biodegradation potential of marine microorganisms from three water depths in the Campos Basin (South Atlantic Ocean): (i) 5 m (surface), (ii) ∼80 m (chlorophyll maximum layer), and (iii) ∼1200 m (near the bottom). After incubating seawater samples with or without crude oil for 52 days, we used metagenomics and classic microbiology techniques to analyze microbial abundance and diversity, and measured physical-chemical parameters to better understand biodegradation processes. We observed increased microbial abundance and concomitant decreases in dissolved oxygen and hydrocarbon concentrations, indicating oil biodegradation in the three water depths treatments within approximately 27 days. An increase in metagenomic sequences of oil-degrading archaea, fungi, and bacteria (Alcanivorax, Alteromonas, Colwellia, Marinobacter, and Pseudomonas) accompanied by a significant increase in metagenomic sequences involved in the degradation of aromatic compounds indicate that crude oil promotes the growth of microorganisms with oil degradation potential. The abundance of genes involved in biodegrading benzene, toluene, ethylbenzene, xylene, alkanes, and poly-aromatic hydrocarbons peaked approximately 3 days after oil addition. All 12 novel metagenome-assembled genomes contained genes involved in hydrocarbon degradation, indicating the oil-degrading potential of planktonic microbes in the Campos Basin.

The ground-level ozone (O₃) concentration in the urban regions of China has become an increasingly noticeable environmental problem in recent years. Many epidemiological studies have reported the association between O₃ pollution and mortality, only a few studies have focused on the O₃-related mortality and corresponding economic effects at the Chinese city and province level. This study reports the seasonal variation of ground-level O₃ in 338 cities of China during the year 2016 and evaluates its effect on premature mortality and economic loss. It further illustrates the differences in cause-specific mortality outcomes of the log-linear and linear model, two of the prominently used methods for estimating health effects. In 2016, the annual average daily maximum 8-h O₃ concentration in China ranged between 74 and 201 μg/m³ (138 ± 24.7 μg/m³). 30% of the total population was exposed to >160 μg/m³ O₃ concentration (Chinese national ambient air quality standard) and about 67.2% urban population lived in exposure above the WHO recommended O₃ concentrations (100 μg/m³). The estimated national O₃-attributable mortality was 74.2 × 10³ (95% CI: 16.7×10³–127×10³) in the log-linear model, whereas, the total O₃-related mortality using the linear model was 69.6 × 10³ (95% CI: 16.2 × 10³–115 × 10³). The exposure to O₃ caused a nationwide economic loss of about 7.6 billion US$ (range: 1.7–12.9) in 2016. This study uniquely provides most comprehensive coverage of the Chinese cities for O₃ associated mortality utilizing ground level measurement data for 2016 and presents a measurable assessment to the policymakers of China for streamlining their efforts on air quality improvement and O₃ containment.

Forecasting wastewater discharge is the basis for wastewater treatment and policy formulation. This paper proposes a novel mixed-data sampling regression model, i.e., combination-MIDAS model to forecast quarterly wastewater emissions in China based on dynamic factors at different frequencies. The results show that a significant auto-correlation for wastewater emissions exists and that water consumption per ten thousand gross domestic product is the best predictor of wastewater emissions. The forecast performances of the combination-MIDAS models are robust and better than those of the benchmark models. Therefore, the combination-MIDAS models can better capture the characteristics of wastewater emissions, suggesting that the proposed method is a good method to deal with model misspecification and uncertainty for the control and management of wastewater discharge in China.

Increased public awareness of the health impacts of atmospheric fine particulate matter (PM₂.₅) has led to increased demand and deployment of indoor air cleaners. Yet, questions still remain about the effectiveness of indoor air cleaners on indoor PM₂.₅ concentrations and personal exposure to potentially hazardous components of PM₂.₅. Metals in PM₂.₅ have been associated with adverse health outcomes, so knowledge of their sources in urban indoor and outdoor areas and how exposures are influenced by indoor air cleaners would be beneficial for public health interventions. We collected 48-h indoor, outdoor, and personal PM₂.₅ exposure samples for 43 homes with asthmatic children in suburban Shanghai, China during the spring months. Two sets of samples were collected for each household, one set with a functioning air filter placed in the bedroom (“true filtration”) and the other with a non-functioning (“sham”) air cleaner. PM₂.₅ samples were analyzed for elements, elemental carbon, and organic carbon. The major sources of metals in PM₂.₅ were determined by Positive Matrix Factorization (PMF) to be regional aerosol, resuspended dust, residual oil combustion, roadway emissions, alloy steel abrasion, and a lanthanum (La) and cerium (Ce) source. Under true filtration, the median indoor to outdoor percent removal across all elements increased from 31% to 78% and from 46% to 88% across all sources. Our findings suggest that indoor air cleaners are an effective strategy for reducing indoor concentrations of PM₂.₅ metals from most sources, which could translate into improved health outcomes for some populations.

Spread of pathogens in pig farms not only causes transfection of diseases to other pigs or even farmers working in the farms, but also induces pollution to the living atmospheric environment of the residents around the farm. Therefore, it is necessary to establish a rapid and simple monitoring method. In this study, full genome sequences of common viruses were analyzed in pig farms, in combination with the design of primers, optimization of the reaction parameters, so as to establish a multiplex RT-PCR assay for the identification of classical swine fever virus (CSFV), Japanese encephalitis virus (JEV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus Type 2 (PCV-2), porcine pseudorabies virus (PRV) and porcine parvovirus virus (PPV), which are common in pig farms. This method has a minimal detectable concentration of 10⁻³ ng/μL, which is highly specific. Furthermore, multiplex RT-PCR was applied to examine air samples from 4 pig farms located in different cities of China. The results were in line with those obtained by single PCR. Therefore, this study can be expected to provide essential technique support for the early warning mechanism as well as disease prevention and control system against the major viruses.

Coral reefs are increasingly affected by the consequences of global change such as increasing temperatures or pollution. Lately, microplastics (i.e., fragments < 5 mm) have been identified as another potential threat. While previous studies have assessed short-term effects caused by high concentrations of microplastics, nothing is known about the long-term effects of microplastics under realistic concentrations. Therefore, a microcosm study was conducted and corals of the genera Acropora, Pocillopora, Porites, and Heliopora were exposed to microplastics in a concentration of 200 particles L⁻¹, relating to predicted pollution levels. Coral growth and health, as well as symbiont properties were studied over a period of six months. The exposure caused species-specific effects on coral growth and photosynthetic performance. Signs of compromised health were observed for Acropora and Pocillopora, those taxa that frequently interact with the particles. The results indicate elevated energy demands in the affected species, likely due to physical contact of the corals to the microplastics. The study shows that microplastic pollution can have negative impacts on hermatypic corals. These effects might amplify corals' susceptibility to other stressors, further contributing to community shifts in coral reef assemblages.