Volatile organic compounds (VOCs) are important precursors of photochemical pollution. However, a substantial fraction of VOCs, namely, oxygenated VOCs (OVOCs), have not been sufficiently characterized to evaluate their sources in air pollution in China. In this study, a total of 119 VOCs, including 60 OVOCs in particular, were monitored to provide a more comprehensive picture based on different online measurement techniques, proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF-MS) and online gas chromatography/mass spectrometry (GC/MS), at a receptor site in southeastern China during a photochemically active period. Positive matrix factorization (PMF) and photochemical age-based parameterization were combined to identify and quantify different sources of major VOCs during daytime hours, with the advantage of including VOC decay processes. The results revealed the unexpected role of biomass burning (21%) in terms of ozone (O₃) formation potential (OFP) when including the contributions of OVOCs and large contributions (30–32%) of biomass burning to aldehydes, as more OVOCs were measured in this study. We argue that biomass burning could significantly enhance the continental atmospheric oxidizing capacity, in addition to the well-recognized contributions of primary pollutants, which should be seriously considered in photochemical models and air pollution control strategies.

Volatile organic compounds (VOCs) poses a serious health risk through not only their own toxicity but also their role as precursors of ozone and secondary organic aerosols. The chemical industry, as one of the pillar industries in eastern China, is a key source of VOCs emissions. In this study, speciated VOCs emissions were measured in two chemical plants in eastern China. Oxygenated VOCs and aromatics were found to be the dominant species categories in both plants. The ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP) of VOCs from dedicated resin production were both higher than general resin production. Three process-based models were used for the estimation of VOCs emissions from the two tested plants as a case study. The comparison between the emission factor model and the model with best available estimation methods (e.g., the measurement-based method, the mass balance method, the empirical formula method, and the correlation equation method) implied possible overestimation of the widely used emission factor model for the chemical industry. The probabilistic model developed in this study incorporated probability distribution of key parameters and proved to be a promising tool for emission inventory development and uncertainty analysis. The overall uncertainties of VOCs emissions based on the model were (−48%, +147%) and (−48%, +139%) for the two tested plants. In this study, the speciation profiles and estimation methodology for VOCs emissions from the chemical industry in China were both improved, which could benefit the accurate evaluation of the impacts of VOCs emissions.

Inhalation of airborne antibiotic resistance genes (ARGs) can lead to antimicrobial resistance and potential health risk. In modern society, increasing individuals stay more indoors, however, studies regarding the exposure to airborne ARGs in indoor environments and the associated risks remain limited. Here, we compared the variance of aerosol-associated ARGs, bacterial microbiomes, and their daily intake (DI) burden in dormitory, office, and outdoor environments in a university in Tianjin. The results indicated that compared to outdoor aerosols, indoors exhibited significantly higher absolute abundance of both ARG subtypes and mobile genetic elements (MGEs) (1–7 orders of magnitude), 16S rRNA genes (2–3 orders), and total culturable bacteria (1–3 orders). Furthermore, we observed that significantly different airborne bacterial communities are the major drivers contributing to the variance of aerosol-associated ARGs in indoor and outdoor aerosols. Notably, the high abundances of total bacteria, potential pathogenic genera, and ARGs (particularly those harbored by pathogens) in indoor and outdoor aerosols, especially in indoors, may pose an increased exposure risk via inhalation. The successful isolation of human pathogens such as Elizabethkingia anopheles, Klebsiella pneumonia, and Delftia lacustris resistant to the “last-resort” antibiotics carbapenems and polymyxin B from indoor aerosols further indicated an increased exposure risk in indoors. Together, this study highlights the potential risks associated with ARGs and their inhalation to human health in indoor environments.

In this study, the biochar (BC) supported Fe–Cu bimetallic stabilized by PVP (Fe–Cu/PVP/BC) were prepared and utilized to enhance the nitrate (NO₃⁻) removal and the selectivity toward nitrogen (N₂). Results showed the optimum Fe:Cu:BC ratio and the dosage of the BC (pyrolysis at 700 °C) supported Fe–Cu bimetallic stabilized by polyvinylpyrrolidone (PVP) (Fe–Cu/PVP/BC₇₀₀) were respectively 1:2:3 and 1 mg L⁻¹ with the selectivity toward N₂ of 31 %. This was mainly due to the synergy among Fe⁰, Cu⁰ and BC in the Fe–Cu/PVP/BC. The addition of Fe⁰ could reduce the NO₃⁻ through providing electron. The Cu⁰ and BC improved the selectivity of NO₃⁻ to N₂ through forming [Cu–NO₂⁻ₐdₛ] and adjusting redox potential. The addition of Fe–Cu/PVP/BC could supply electrons for denitrification and enhance the relative abundances of Azospira and Thauera related to denitrification to improve NO₃⁻ removal. This result was further confirmed by the variations of denitrifying functional genes (narG, nirK, nirS and nosZ). This research provided an effective method to improve NO₃⁻ removal during surface water treatment in constructed wetlands (CWs) by adding Fe–Cu/PVP/BC.

Thermogravimetric analysis and pyrolyzer-gas chromatography/mass spectrometry measurements were taken to examine the kinetic behavior and product distribution on the thermal and catalytic pyrolysis of different types of sewage sludge. Compared to livestock manure sewage sludge (LMSS), municipal sewage sludge (MSS) had larger ash (30.3%) and lower fixed carbon (7.9%) contents. The peak intensities for the 1ˢᵗ decomposition region (200–380 °C) on the derivative thermogravimetric curve of MSS were higher than those of LMSS. In contrast, the peak height in the 2ⁿᵈ temperature region (>380 °C) of MSS was lower than that of LMSS. The activation energy for the pyrolysis of MSS (Avg. 186.5 kJ/mol) was lower than that of LMSS (Avg. 263.4 kJ/mol) over the entire conversion range. MSS produced larger amounts of fatty acids and cholesterol than LMSS. The in-situ catalytic pyrolysis of MSS over HBeta using a pyrolyzer-gas chromatography/mass spectrometry also produced larger amounts of aromatic hydrocarbons than LMSS, suggesting that its better feedstock properties strongly influence the final product oil quality.

Chemicals such as triclosan are a concern because of their presence on daily products (soap, deodorant, hand sanitizers …), consequently this compound has an ubiquitous presence in the environment. Little is known about the effect of this bactericide on aquatic life. The aim of this study is to analyze triclosan exposure (24 h) to an in vitro model, zebrafish hepatocytes cell line (ZF-L), if it can be cytotoxic (mitochondrial activity, membrane stability and apoptosis) and if can activate ATP-binding cassette (ABC) proteins (activity, expression and protein/compound affinity). Triclosan was cytotoxic to hepatocytes when exposed to concentrations (1–4 mg/L). The results showed impaired mitochondria function, as well, plasma membrane rupture and an increase of apoptotic cells. We observed an ABC proteins activity inhibition in cells exposed to 0.5 and 1 mg/L. When ABCBs and ABCC2 proteins expression were analyzed, there was an increase of protein expression in both ABC proteins families on cells exposed to 1 mg/L of triclosan. On molecular docking results, triclosan and the fluorescent used as substrate (rhodamine) presented high affinity with all ABC proteins family tested, showing a greater affinity with ABCC2. In conclusion, this study showed that triclosan can be cytotoxic to ZF-L. Molecular docking indicated high affinity between triclosan and the tested pumps.

A paradoxical impact of high rates of production and consumption of antibiotics is their widespread release in the environment. Consequently, low concentrations of antibiotics and their byproducts have been routinely identified from various environmental settings especially from aquatic environments. However, the impact of such low concentrations of antibiotics on the exposed host especially in early life remains poorly understood. We exposed zebrafish to two different environmental concentrations of oxytetracycline and sulfamethoxazole, from larval stage to adulthood (∼120 days) and characterized their impact on the taxonomic diversity, antibiotic resistance genes, and metabolic pathways of the gut microbiome using metagenomic shotgun sequencing and analysis. Long term exposure of environmental concentrations of oxytetracycline and sulfamethoxazole significantly impacted the taxonomic composition and metabolic pathways of zebrafish gut microbiome. The antibiotic exposed samples exhibited significant enrichment of multiple flavobacterial species, including Flavobacterium sp. F52, Flavobacterium johnsoniae and Flavobacterium sp. Fl, which are well known pathogenic bacteria. The relative abundance of antibiotic resistance genes, especially several tetratcycline and sulfonamide resistance genes were significantly higher in the exposed samples and showed a linear correlation with the antibiotic concentrations. Furthermore, several metabolic pathways, including folate biosynthesis, oxidative phosphorylation, and biotin metabolism pathways, showed significant enrichment in the antibiotic exposed samples. Collectively, our results suggest that early life exposure of the environmental concentrations of antibiotics can increase the abundance of unfavorable bacteria, antibiotic resistance genes and associated pathways in the gut microbiome of zebrafish.

This systematic review and meta-analysis evaluates the most recent evidence to examine whether use of improved biomass cookstoves in households in low-middle income countries results in reduction in mean concentrations of carbon monoxide (CO) and particulate matter of size 2.5 μm (PM₂.₅) in the cooking area, as well as reduction in mean systolic (SBP) and diastolic blood pressure (DBP) of adults using the cookstoves when compared to adults who use traditional three stone fire or traditional biomass cookstoves.We searched databases of scientific and grey literature. We included studies if published between January 2012 and June 2021, reported impact of ICS interventions in non-pregnant adults in low/middle-income countries, and reported post-intervention results along with baseline of traditional cookstoves. Outcomes included 24- or 48-h averages of kitchen area PM₂.₅, CO, mean SBP and DBP. Meta-analyses estimated weighted mean differences between baseline and post-intervention values for all outcome measures.Eleven studies were included; ten contributed estimates for HAP and four for BP. Interventions lead to significant reductions in PM₂.₅ (−0.73 mg/m³, 95% CI: −1.33, −0.13), CO (−8.37 ppm, 95%CI: −13.20, −3.54) and SBP (−2.82 mmHg, 95% CI: −5.53, −0.11); and a non-significant reduction in DBP (−0.80 mmHg, 95%CI: −2.33, 0.73), when compared to baseline of traditional cookstoves. Except for DBP, greatest reductions in all outcomes came from standard combustion ICS with a chimney, compared to ICS without a chimney and advanced combustion ICS.Among the reviewed biomass stove types, ICS with a chimney feature resulted in greatest reductions in HAP and BP.

The influence of intercalated anions on the structure and composition of green rusts supplies a theoretical possibility for the investigation of the structural modification of Feᴵᴵ/Feᴵᴵᴵ (oxyhydr)oxide materials. β-Cyclodextrin was intercalated into the mixed-valent iron-based hydroxide layers to synthesize new green rust materials (β-CD GRs), pursuing high-capacity uraniumⱽᴵ (Uⱽᴵ) sorption. The molar ratios of Feᴵᴵ to Feᴵᴵᴵ and the molar ratios of β-CD GR to Feᴵᴵ + Feᴵᴵᴵ had a significant effect on the synthesis of β-CD GRs. The synthesis process was further optimized by the quadric predictor and desirability function in a central composite design in combination. Both strong acidity and alkalinity were harmful to the adsorption of β-CD GRs towards Uⱽᴵ. The pseudo-first-order kinetic model and Langmuir isotherm model were appropriate in fitting the whole adsorption process. The maximum monolayer adsorption capacity of β-CD GRs was 2548.61 mg/g. The presence of mimic groundwater constituents explicitly deteriorated the interaction between β-CD GR and Uⱽᴵ species. Nanoscale nodules and particles were formed on the β-CD GR after the adsorption experiments. The peaks at 1159 and 609 cm⁻¹ vanished with the band at 1103 cm⁻¹ being left-shifted to 1117 cm⁻¹ in the FTIR spectra of β-CD GR during the heterogeneous process. The intercalation of β-CD brought obvious enhancement of Uⱽᴵ species sorption to the GR material, which was combinedly driven by several reaction pathways and different from the unmodified GRs.

It is a common practice to maintain soil fertility based on the paddy-upland rotation with green manure in the subtropical region of China. However, rare studies are known about greenhouse gas (GHG) emissions from the paddy-upland rotation with green manure incorporation. Therefore, we conducted a field experiment of two years to compared with the effect of two kinds of green manure (CV: Chinese milk vetch and OR: Oilseed rape), and two kinds of cropping system (DR: double rice system and PR: paddy-upland rotation) on greenhouse gases emissions. We have found that the annual accumulation of CH₄ of Chinese milk vetch-rice-sweet potato || soybean was significantly reduced by 32.95%∼63.22% compared with other treatments, mainly because Chinese milk vetch reduced the abundance of methanogens by reducing soil C/N ratio. Meanwhile increasing soil permeability resulting from paddy-upland rotation also reduced soil CH₄ emission. However, The annual accumulation of N₂O of Chinese milk vetch-rice-sweet potato || soybean was increased by 17.39%∼870.11% compared with other treatments, mainly attributed to paddy-upland rotation decreased soil pH and nosZ abundance and increased nirK and nirS, thus enhancing N₂O emission, meanwhile the Chinese milk vetch incorporation and its interaction with the paddy-upland rotation has greatly enhanced the contents of NO₃⁻-N and abundance of ammonia-oxidizing archaea (AOA). The area-scaled global warming potential (GWP) and the biomass-scaled greenhouse gas emissions intensity (GHGI) of Chinese milk vetch-rice-sweet potato || soybean was reduced by 19.01%∼50.69% and 5.38%∼35.77% respectively. Thereby, the Chinese milk vetch-rice-sweet potato || soybean cropping system was suitable for agricultural sustainable development.