Search

The effect of physical activity on hip/knee osteoarthritis (OA) and how it varies by genetic susceptibility to OA remains inconclusive.In a cohort study of UK Biobank, 436,166 OA-free participants were recruited in 2006-2010 and followed for knee/hip OA until the end of 2020. 28 physical activity-related items were collected at baseline. Cox regression was used to estimate associations between physical activity behaviors, as well as major activity patterns (i.e., significant principal components[PCs] identified by principal component analysis), and risk of OA, adjusting for multiple confounders. We further stratified the analyses by polygenic risk score (PRS) for OA to examine the impact of genetic susceptibility to OA on the studied association.During a mean follow-up of 11.15 years, 13,227 hip and 21,119 knee OA cases were identified. 19, out of 28, studied items showed associations with increased OA risk. Compared with low adherence group(1High intensity of most activity patterns were associated with increased OA. However, a protective effect was suggested for moderate adherence to patterns of "strenuous sports" and "walking for pleasure" that consistent across different genetic susceptibilities, underscoring the potential benefits of moderate-intensity physical activity on OA.

The intrinsic mechanical and interfacial characteristics of precipitates in Mg–Sn–Y alloys were calculated to predict strengthening precipitates and to design novel Mg alloys. The first-principle calculations results indicated that the Sn3Y5 phase had a higher bulk and shear moduli than the Mg24Y5 and Mg2Sn phases. The Mg/Sn3Y5 interface was more stable and possessed a higher adhesive strength than the Mg/Mg2Sn and Mg/Mg24Y5 interfaces. Four as-cast alloys (S10Y3 (Mg-0.5Sn-0.16Y), S5Y3 (Mg-0.43Sn-0.25Y), S1Y1 (Mg-0.36Sn-0.37Y) and S3Y5 (Mg-0.27Sn-0.48Y) alloy (at.%)) were then designed according to the different Sn to Y atomic ratios (10:3, 5:3, 1:1 and 3:5). The lower Sn to Y atomic ratio promoted the formation of the Sn3Y5 phase in the S3Y5 alloy, whereas the S10Y3 alloy with a higher Sn to Y atomic ratio mainly consisted of the Mg2Sn phase. Compared with the S10Y3 alloy, the yield strength and ultimate tensile strength of the S3Y5 alloy were increased by 70% and 16% without sacrificing the elongation at room temperature, which was greatly improved by 127% and 104% at elevated temperatures simultaneously. These results suggested that the calculations of intrinsic mechanical and interfacial characteristics of precipitates may provide an effective tool to design high-strength Mg alloys.

Infrared metasurface, especially that having a working range covering wavelengths from 0.75 to 25 μm, has been exploited as a revolutionary tool to manipulate the properties of electromagnetic waves owing to its potential applications in military and civilian fields. It owns the capacity to steer electromagnetic waves within subwavelength scale, with full degrees of freedom such as phase, amplitude and polarization, allowing the development of a number of planar meta-devices including the metalens, hologram, wave-plate and polarimeter. In particular, polarization, which determines the interaction of electromagnetic waves with matter, is important in almost every area of science. However, conventional materials for infrared polarization control inevitably introduce extra optical components and bulky configurations, hindering future miniaturization and integration. Moreover, compared with their short wavelength counterparts, polarization nanodevices in the infrared band and especially those in the long-wavelength infrared region have been far less explored due to the loss of material and immature fabrication techniques. Here, we review recent progress in the development of infrared metasurfaces in terms of generating, manipulating and detecting the polarization on standard and higher-order Poincare spheres. The principles, typical strategies and emerging applications of these processes are introduced. We also discuss the challenges and outlook of future developments in this emerging field.

Environmental science is an interdisciplinary science developed in the process of understanding and solving ecological and environmental problems. In order to tackle these problems, environmental science research is expected to reveal the source, behavior, fate, exposure, and risks of pollutants in the environment and develop potential solutions to control pollution. It provides the scientific basis for decision-makers to establish environmental and economic policies, and promote concerted efforts for the sustainable development of society. Here, we articulate the development patterns, challenges, and future research needs of environmental science in China based on literature review and expert panel discussion. Environmental science research has evolved significantly in the past decade with an increasing diversity of environmental pollutants and health impacts, new technologies and methods, deepening fusion of multiple disciplines, and emerging solutions for pollution control. Its future development relies on the advances in our knowledge on the fate and transport of pollutants, regional environmental processes, ecotoxicological effects, environmental exposure and health effects, environmental analysis and monitoring, source control and reduction, environmental remediation, as well as environmental risk management. For each of these fields, we summarize the significant challenges and highlight the research demands for China. Based on the status quo of China's environmental science research and future needs, we provide recommendations to promote its future development, including encouraging innovation and interdisciplinary research, providing decision support for national needs, encouraging international collaboration, and improving collaboration mechanisms.

The brain of the domestic pig (Sus scrofa domesticus) has drawn considerable attention due to its high similarities to that of humans. However, the cellular compositions of the pig brain (PB) remain elusive. Here we investigated the single-nucleus transcriptomic profiles of five regions of the PB (frontal lobe, parietal lobe, temporal lobe, occipital lobe, and hypothalamus) and identified 21 cell subpopulations. The cross-species comparison of mouse and pig hypothalamus revealed the shared and specific gene expression patterns at the single-cell resolution. Furthermore, we identified cell types and molecular pathways closely associated with neurological disorders, bridging the gap between gene mutations and pathogenesis. We reported, to our knowledge, the first single-cell atlas of domestic pig cerebral cortex and hypothalamus combined with a comprehensive analysis across species, providing extensive resources for future research regarding neural science, evolutionary developmental biology, and regenerative medicine.

Nanoplastics (NPs) are emerging contaminants in the environment, where the transport and fate of NPs would be greatly affected by interactions between NPs and minerals. In the present study, the interactions of two types of polystyrene nanoplastics (PSNPs), i.e., bare-PSNPs and carboxylated PSNPs-COOH, with iron (hydr)oxides (hematite, goethite, magnetite, and ferrihydrite), aluminum (hydr)oxides (boehmite and gibbsite), and clay minerals (kaolinite, montmorillonite, and illite) were investigated. The positively charged iron/aluminum (hydr)oxide minerals could form heteroaggregates with negatively charged PSNPs. Electrostatic and hydrophobic interaction dominate for the heteroaggregation of bare-PSNPs with iron/aluminum (hydr)oxide minerals, while ligand exchange and electrostatic interaction are involved in the heteroaggregation of PSNPs-COOH with iron/aluminum (hydr)oxides minerals. However, heteroaggregation between PSNPs and negatively charged clay minerals was negligible. Humic acid markedly suppressed such heteroaggregation between PSNPs and minerals due to enhanced electrostatic repulsion, steric hindrance, and competition of surface attachment sites. The heteroaggregation rates of both bare-PSNPs and PSNPs-COOH with hematite decreased with increasing solution pH. Increased ionic strength enhanced the heteroaggregation of PSNPs-COOH but inhibited that of bare-PSNPs. The results of the present study suggested that the heteroaggregation of PSNPs in environments could be strongly affected by minerals, solution pH, humic acid, and ionic strength.

IκB kinase α (IKKα) is associated with tumourigenesis, metastasis, and poor prognosis. However, its expression and function in oral squamous cell carcinoma (SCC) remain unknown. The aim of this study was to elucidate the clinicopathological associations and functions of IKKα in oral squamous cell carcinoma (SCC). We made an immunohistochemical analysis of IKKα in 94 tissue microarrays of specimens of oral SCC. We also examined IKKα expression in the patients' samples by quantitative real-time polymerase chain reaction (qRT-PCR), as well as the migration, invasion, and matrix metalloproteinase (MMP) activity of the cells under IKKα knockdown treatment. In oral SCC, immunostaining for IKKα was found in 60 of the 94 patients, and it correlated with lymph node status and poor prognosis. Univariate and multivariate analysis using Cox's proportional hazards model identified that IKKα expression was an independent predictor of distant- disease-free survival (p

Biobased plastic exhibits unique benefits for achieving carbon neutrality, a key step toward reducing atmospheric greenhouse gases, due to its stability, high carbon content, and origin of carbon by photosynthesis. Herein we evaluate the role and potential of biobased plastic as an alternative carbon reservoir which is completely artificial, since most plastic polymers are synthetic and massively produced after the 1950 s. Model simulation indicates that plastic, under usage, burial, and littering, forms a growing carbon reservoir, sinking 6.82 gigatons of carbon (GtC) in 2020. Plastic-formed carbon is estimated to stack up to 19.4-23.2 GtC in 2060 under various production scenarios. However, only 18-40% of carbon stored in plastic is biobased carbon, equivalent to approximately 31-48 gigatons of carbon dioxide. Without any low carbon energy upgrade, carbon neutrality is difficult to achieve even with 90% biobased plastic substitution and 50% recycling ratio. Because extra GHG emissions are generated as a result of increasingly using incineration as a post-treatment strategy in response to increasing waste generation, the annual net GHG emission continues to rebound after the bio-based plastic substitution and plastic recycling approach their upper limits. Additional strategies are therefore needed to achieve complete carbon neutrality.

The occurrence of microplastics (MPs) in the environment has been gaining widespread attention globally. MP-colonizing microorganisms are important links for MPs contamination in various ecosystems, but have not been well understood. To partially address this issue, the present study investigated biofilm formation by microorganisms originating from lake water on low-density polyethylene (LDPE) MPs using a cultivation approach and the surface-related effects on the MP-associated microbial communities using 16S rRNA high-throughput sequencing. With the addition of nonionic surfactants and UV-irradiation pretreatment that changed the surface properties of LDPE MPs, more microorganisms were colonized on LDPE surface. Microbial community analysis indicated that LDPE MPs were primarily colonized by the phyla Proteobacteria, Bacteroidetes and Firmicutes, and the surface roughness and hydrophobicity of MP were important factors shaping the LDPE MP-associated microbial community structure. Half of the top 20 most abundant genera colonizing on LDPE were found to be potential pathogens, e.g., plant pathogens Agrobacterium, nosocomial pathogens Chryseobacterium and fish pathogens Flavobacterium. This study demonstrated rapid bacterial colonization of LDPE MPs in lake water microcosms, the role of MPs as transfer vectors for harmful microorganisms in lake water, and provided a first glimpse into the effect of surface properties on LDPE MP-associated biofilm communities.

The interaction of pollutants with nanomaterials has attracted attention due to the extensive application of nanomaterials. In this study, the adsorption behavior of PFOS on nano-alumina with different shapes was investigated. First, the adsorption isotherms and kinetics of PFOS on alumina nanoparticles (NPs) and nanowires (NWs) were measured to calculate thermodynamic parameters. The effects of solution chemistry (e.g., pH, ionic strength, and the presence of humic acid) on adsorption were further studied. The different aggregation behavior of alumina NPs and NWs were the critical factor for PFOS adsorption, as demonstrated through dynamic light scattering (DLS) experiments. This study is the first to investigate the aggregation effects on PFOS adsorption on nanomaterials and the results should be useful in identifying the important roles of shape and aggregation of nanomaterials on the fate of organic pollutants in the environment.

Indoor air contributes significantly to overall exposure, particularly for rural Chinese who often use solid fuels for cooking and/or heating. Unfortunately, overlooked rural indoor air leads to a critical knowledge gap. Simultaneous measurements in the kitchen, living room, and immediately outside of houses using six-channel particle counters were carried out in 18 biomass-burning rural and 3 non-biomass-burning urban households (as a comparison) in winter to characterize dynamic change patterns indoor air pollution and indoor-outdoor relationship. The rural households mainly used wood or crop residues for cooking and heating, while the urban households used pipelined natural gas for cooking and air conditioners for heating. In rural households with significant solid-fuel burning internal sources, the highest concentration was found in the kitchen (101 ± 56 μg/m3), with comparable levels in the living room (99 ± 46 μg/m3) and low levels in outdoor air (91 ± 39 μg/m3). A generally opposite direction of indoor-outdoor exchange was found between the rural and urban households. PM in kitchen air is smaller than that in living rooms and outdoors because solid fuel burning (mainly in rural households) and cooking oil heating (in rural and urban households). Indoor and outdoor PM concentration changed synchronously, with a slight delay in indoor air in urban households but a slight delay in outdoor air in rural households. Cooking, heating, and smoking elevated indoor PM significantly, but different from the cooking activity that produced peaks lasting for about 30 min, emissions from heating created a series of peaks due to frequent disturbance and fuel-feeding and had more significant impacts on the daily average concentration. Distinct indoor-outdoor relationships and dynamic change patterns between the two household categories w/o strong internal biomass burning sources imply that totally different model schemes are needed to quantitatively address indoor air pollution and inhalation exposure.

The potential adverse effects of microplastics (MPs) on ecosystems and human health have received much attention in recent years. However, only limited data are available on the mechanisms for the uptake, distribution, and effects of MPs in freshwater organisms, especially with respect to tissue repair, regeneration and impairment of stem cell functions. To address this knowledge gap, we conducted exposure experiments in which planarians (Dugesia japonica) were exposed to polystyrene (PS)-MPs mixed in liver homogenate and examined the tissue growth and regeneration, stem cell functions, and oxidative stress. The body and blastema areas decreased upon exposure to PS-MPs, indicating that the growth and regeneration of planarians were delayed. The proliferation and differentiation processes of stem cells were inhibited, and the proportion of mitotic stem cells decreased, which may be related to the activation of the TGFβ/SMAD4 and Notch signaling pathways. The enhancement of antioxidant enzyme activities and malondialdehyde on the first day of exposure to PS-MPs confirmed the oxidative stress response of planarians to PS-MPs. The present study demonstrated the likelihood of biotoxicity induced by PS-MPs. These results will provide clues for further investigations into the potential risks of PS-MPs to human stem cells.

Influence of sediment particle size on the desorption, bioavailability, and bioaccumulation potential of cypermethrin was investigated in the present study using two biomimetic techniques (Tenax extraction and solid-phase microextraction (SPME)) and bioaccumulation testing with Lumbriculus variegatus. A field-collected sediment was wet sieved to obtain five particle-size fractions (20, 20-63, 63-180, 180-500, and500 μm) and used for cypermethrin spiking. The finest sediment (20 μm) had the highest rapid desorption fraction (F

Sludge disposal such as land application is suspected as a significant source of microplastic (MP) pollution in the environment. To examine such a hypothesis, the present study was conducted to investigate the occurrence of MPs in sludge by analyzing 79 sewage sludge samples collected from 28 wastewater treatment plants (WWTPs) in 11 Chinese provinces. MP concentrations in the sludge samples ranged from 1.60–56.4 × 103 particles per kilogram of dry sludge, with an average of 22.7 ± 12.1 × 103 particles per kilogram of dry sludge. Thereinto, the sludge-based MP contents were greater in eastern China than in western China and varied during different months. Their colors and types were mainly white (59.6%) and fibers (63%), respectively. Microscope Fourier Transform infrared spectroscopy revealed that most of MPs belonged to polyolefin, acrylic fibers, polyethylene and polyamide. Some WWTP parameters, such as servicing area, proportion of industrial wastewater, secondary treatment and sludge dewatering may have affected MP concentrations in sludge. Based on the total sludge production in China, the average amount of sludge-based MPs entering into natural environmental was estimated to be 1.56 × 1014 particles per year. The findings confirmed that sewage sludge discharge is an important source of MP pollution in the environment. Further evaluation of the associated environmental hazards with MPs is deemed necessary.

Urban residents spend the majority of time in indoor environments, which, however, may not be a safe haven for staying away from outdoor air pollution, especially in China. To examine this hypothesis, the particle mass concentrations (0.056–18 μm) and number concentrations (14–660 nm) were simultaneously measured in and outside of three typical urban indoor settings (n = 9), i.e., school, office and residence in Guangzhou, China from October–November 2014 (dry weather season) and June–August 2015 (wet weather season). The indoor and outdoor particle number concentrations were positively correlated with each other at all three sampling settings for both dry and wet weather seasons (r2 = 0.13–0.65, p

Barbecue (BBQ) is one of the most popular cooking activities with charcoal worldwide and produces abundant polycyclic aromatic hydrocarbons (PAHs) and particulate matter. Size distribution and clothing-air partitioning of particle-bound PAHs are significant for assessing potential health hazards to humans due to exposure to BBQ fumes, but have not been examined adequately. To address this issue, particle and gaseous samples were collected at 2-m and 10-m distances from a cluster of four BBQ stoves. Personal samplers and cotton clothes were carried by volunteers sitting near the BBQ stoves. Particle-bound PAHs (especially 4–6 rings) derived from BBQ fumes were mostly affiliated with fine particles in the size range of 0.18–1.8 μm. High molecular-weight PAHs were mostly unimodal peaking in fine particles and consequently had small geometric mean diameters and standard deviations. Source diagnostics indicated that particle-bound PAHs in BBQ fumes were generated primarily by combustion of charcoal, fat content in food, and oil. The influences of BBQ fumes on the occurrence of particle-bound PAHs decreased with increasing distance from BBQ stoves, due to increased impacts of ambient sources, especially by petrogenic sources and to a lesser extent by wind speed and direction. Octanol-air and clothing-air partition coefficients of PAHs obtained from personal air samples were significantly correlated to each other. High molecular-weight PAHs had higher area-normalized clothing-air partition coefficients in cotton clothes, i.e., cotton fabrics may be a significant reservoir of higher molecular-weight PAHs. Capsule Particle-bound PAHs from barbecue fumes are generated largely from charcoal combustion and food-charred emissions and mainly affiliated with fine particles.

Microplastics (MPs) are ubiquitous in various environment compartments, including food. Here, we collected research reports of MPs in food published during 2010–2020, and summarized the analytical methods developed and utilized by researchers (e.g., digestion, separation and identification, as well as related QA/QC measures implemented), the occurrence, and the characteristics of MPs in six kinds of food. The potential effects on biota from exposure to MPs were also reviewed. The results showed that most researchers digested food samples using chemical solutions such as HNO3, H2O2, KOH, or NaOH. FT-IR and Raman spectroscopy were the main technique for identifying MPs, and microscopes were used to count MP particles. The abundances MPs were in the ranges of 0–5860, 2.00–1100, 0–698, 4.00–18.7, 0–5.68 × 104 and 900–3000 particles/kg in beverages, condiments, honey, meat, seafood and vegetables, respectively. The “maximum” annual human intake of MPs from these foods is approximately 1.42 × 105–1.54 × 105 particles/capita, equivalent to the consumption of 50 plastic bags (size: 0.04 mm × 250 mm × 400 mm, density: 0.98 g/cm3) each year. Blue-colored and fiber-shaped MP particles were the most commonly observed in food, predominated by PA, PE, PES, PET and PP types. Toxicity studies indicated that MPs, additives of MPs and adsorbents or microorganisms on the surfaces of MPs were all somewhat toxic to cells or biota. Exposure to MPs may induce oxidative stress, inflammation, neurotoxicity, and reproductive toxicity, and change the structure of intestinal microflora in cells or biota. Therefore, we call for more investigation into the residual, excretion and bioavailability of MPs or related absorbents/additives in biota and humans.

Tire-derived particles and polyethylene (PE) debris co-exist in estuaries and potentially deteriorate water quality. Chemicals can be emitted from tire-derived particles and resorb to PE debris. However, there was lack of information about the interaction (e.g., sorption and desorption) between tire-derived chemicals and PE debris. By combining batch sorption and desorption experiments along with in situ field deployment of PE sheets, we examined the utility of benzothiazoles (BTZs) sorbed in PE as suitable markers of tire-derived inputs. The sorptive characteristics and PE-water partition coefficients (often designated as Kpew) of selected tire-derived marker candidates, i.e., polycyclic aromatic hydrocarbons (PAHs), benzothiophenes (BTPs) and BTZs, were measured. Moderately polar BTPs and BTZs (except for 2-(4-morpholinyl) benzothiazole) reached equilibrium within 2-8 days, compared to 20 days for nonpolar PAHs. The measure Kpew values and octanol-water partition coefficients of PAHs and BTZs were linearly correlated with each other (r2 > 0.80; p

Considerable efforts on exposure assessment of microplastics (MPs) as an agent in transport of toxic contaminants have been performed in organisms. However, chemical diffusion of inherent hydrophobic organic contaminants from MPs under simulated gut conditions is poorly examined. The present study examined the transfer kinetics of polybrominated diphenyl ethers (PBDEs) from polystyrene (PS), acrylonitrile butadiene styrene (ABS), and polypropylene (PP) MPs under gut surfactants (sodium taurocholate) at two relevant body temperatures of marine organisms, and evaluated the importance of MP ingestion in bioaccumulation of PBDEs in lugworm by a biodynamic model. Diffusion coefficients of PBDEs range from 5.82 × 10−23 to 7.96 × 10−20 m2 s−1 in PS, 5.49 × 10−23 to 3.45 × 10−20 m2 s−1 in ABS, and 5.58 × 10−21 to 5.79 × 10−17 m2 s−1 in PP, with apparent activation energies in the range of 33–148 kJ mol−1. The biota–plastic accumulation factors of PBDEs leached from these plastics range from 1.44 × 10−8 to 7.15 × 10−5. Although ingestion of MPs with the common size (>0.5 mm) showed the negligible contribution to bioaccumulation of PBDEs in lugworm, their contribution in PBDEs transfer can be increased with gradual breakdown of MPs.

High throughput sequencing of gut microbiota helps to understand the nutrition and health of the host. In this sense, it is an important tool for improving wildlife conservation and management. Little is known about the microbial communities occupying the gastrointestinal tract and the differences of microbiota among primate species. We conducted a microbiome study of the gastrointestinal tract in golden snub-nosed monkey (Rhinopithecus roxellanae), green monkey (Chlorocebus aethiops sabaeus), and ring-tailed lemur (Lemur catta), using the 16S rRNA gene amplicon sequencing and shotgun metagenomic sequencing. The gastrointestinal tract of all three primates were characterized by Firmicutes, Bacteroidetes, and Proteobacteria, although the relative abundance of these taxa differed across non-human primate species and gastrointestinal segments. In addition, the stomach of the golden monkey demonstrated a strong signal of microbial metabolic activity, especially in metabolizing carbohydrate. Prevotella multisaccharivorax and Selenomonas bovis were the main contributors to the function, and the enzymes involved in these metabolic activities were mainly derived from the glycoside hydrolase (GH) family. Microbial composition and function vary widely across non-human primate species and gastrointestinal segments. Therefore, while faecal samples are necessary for studying many mammals, particularly in the wild, data from the gastrointestinal tract have the potential to greatly improve our knowledge of host-gut microbe interactions. This information can contribute to the development of conservation interventions and animal care protocols in the wild and captivity to more fully describe a species’ nutritional needs and advance health and survival.

Using a data sample of 448.1 × 10 6 ψ ( 3686 ) events collected with the BESIII detector at the BEPCII collider, we report the first observation of the electromagnetic Dalitz decay ψ ( 3686 ) → η ′ e + e − , with significances of 7.0σ and 6.3σ when reconstructing the η ′ meson via its decay modes η ′ → γ π + π − and η ′ → π + π − η ( η → γ γ ), respectively. The weighted average branching fraction is determined to be B ( ψ ( 3686 ) → η ′ e + e − ) = ( 1.90 ± 0.25 ± 0.11 ) × 10 − 6 , where the first uncertainty is statistical and the second systematic.

Occurrence of microplastics (MPs) in the environment has attracted great attention as it has become a global concern. This review aims to systematically demonstrate the role of marine microplastic as a novel medium for environmental partitioning of chemicals in the ocean, which can cause toxic effects in the ecological environment. This review assimilated and analyzed available data published between 1972 and 2017 on the interaction between MPs and selected chemicals. Firstly, the review analyzes the occurrence of chemicals in MPs and outlines their distribution patterns. Then possible mechanisms of the interaction between MPs and organic chemicals and potential controlling factors were critically studied. Finally, the hazards of MPs and affiliated organic chemicals to marine organisms were shortly summarized.

Although a number of studies have assessed the occurrence of atmospheric polycyclic aromatic hydrocarbons (PAHs) in indoor environment, few studies have systemically examined the indoor-outdoor interplay of size-dependent particulate PAHs and potential health risk based on daily lifestyles. In the present study, size-dependent particle and gaseous samples were collected both indoors and outdoors within selected schools, offices and residences located in three districts of Guangzhou, China with different urbanization levels during the dry and wet weather seasons. Results from measurements of PAHs showed that higher total PAH concentrations occurred in residential areas than in other settings and in indoor than in outdoor environments. Compositional profiles and size distribution patterns of particle-bound PAHs were similar indoors and outdoors, predominated by 4-and 5-ring PAHs and the 0.56–1.0 μm particle fraction. Statistical analyses indicated that outdoor sources may have contributed to 38–99% and 62–100% of the variations for indoor particle-bound and gaseous PAH concentrations, respectively. Incremental life cancer risk (ILCR) from human exposure to indoor and outdoor PAHs based on different lifestyles followed the order of adults > children > adolescents > seniors. All average ILCR values for four age groups were below the lower limit of the Safe Acceptable Range (10−6). In addition, the ILCR value for adults (average: 7.2 × 10−7; 95% CI: 5.4 × 10−8‒2.5 × 10−6), estimated from outdoor air PAH levels with 24-h exposure time, was significantly higher than our assessment results (average: 5.9 × 10−7; 95% CI: 6.3 × 10−8‒1.9 × 10−6), suggesting the significance of assessing human inhalation exposure risks of indoor and outdoor PAHs in urban air based on daily lifestyles.

In China, rural migrant workers (RMWs) are employed in urban workplaces but receive minimal resources and welfare. Their residential energy use mix (REM) and pollutant emission profiles are different from those of traditional urban (URs) and rural residents (RRs). Their migration towards urban areas plays an important role in shaping the magnitudes and spatial patterns of pollutant emissions, ambient PM2.5 (fine particulate matter with a diameter smaller than 2.5 μm) concentrations, and associated health impacts in both urban and rural areas. Here we evaluate the impacts of RMW migration on REM pollutant emissions, ambient PM2.5, and subsequent premature deaths across China. At the national scale, RMW migration benefits ambient air quality because RMWs tend to transition to a cleaner REM upon arrival at urban areas—though not as clean as urban residents'. In 2010, RMW migration led to a decrease of 1.5 μg/m3 in ambient PM2.5 exposure concentrations (Cex) averaged across China and a subsequent decrease of 12,200 (5700 to 16,300, as 90% confidence interval) in premature deaths from exposure to ambient PM2.5. Despite the overall health benefit, large-scale cross-province migration increased megacities' PM2.5 levels by as much as 10 μg/m3 due to massive RMW inflows. Model simulations show that upgrading within-city RMWs' REMs can effectively offset the RMW-induced PM2.5 increase in megacities, and that policies that properly navigate migration directions may have potential for balancing the economic growth against ambient air quality deterioration. Our study indicates the urgency of considering air pollution impacts into migration-related policy formation in the context of rapid urbanization in China. Keywords: Rural migrant works, Urbanization in China, Ambient air pollution, Particulate matter, Human health

Accumulation of microplastics (MPs) data on a global scale is key to supporting plastic waste management for protecting ecosystems. To respond this call, a sampling campaign was conducted in the summer and winter seasons of 2018 to collect beach and mangrove sediment samples from 32 sites along the coastline of South China. The MPs concentrations in the intertidal zone along the coast of South China were comparable to those in other regions around the world. Polystyrene foams and fibers were the most abundant debris in the 0.2–5 mm and 0.02–2 mm MPs, respectively. Principal component and correlation analyses indicated that the abundances of MPs were related to wind direction, wastewater discharge amount, and tourist and fishing activities. Risk assessments suggested that potential ecological risks induced by MPs on beaches and mangrove forest along the coast of South China should not be overlooked.

Cultivation of microalgae in anaerobically digested effluent is beneficial for removal of nutrients, such as nitrogen and phosphorus, and heavy metals at reduced cost and generation of biomass to produce biofuels. In the present study, four strains of oleaginous microalgae, separated from fresh water in South China, were evaluated for their ability to remove nitrogen and phosphorus. The results showed that Scenedesmus sp. (GN 171) was capable of removing nitrogen and phosphorous in BG-11 medium at the rates of 97% and 99%. Two types of anaerobically digested effluents, i.e., grass anaerobically digested effluent and molasses wastewater anaerobically digested effluent, were chosen as the nutrient sources. These anaerobically digested effluents diluted in BG-11 medium or with tap water were used as the substitute medium to cultivate GN 171; other pretreatment methods, such as sterilization and dilution ratio, were also taken into consideration. A ratio of 1/3 for unsterilized grass anaerobically digested effluent/tap water mixture (designated as G4) was the optimal proportion for growth of GN 171 and removal of nitrogen and phosphorus at a large scale. The dry weight of GN 171 reached 3.2 g L−1, and the total lipid, carbohydrate and protein contents were 34%, 30% and 16% in G4. The efficacies for removal of total nitrogen, ammonia nitrogen, phosphorus and selected heavy metals were generally satisfactory. It seems possible to use ADE, rather than any artificial medium, as the sole nutrient source for microalgae production.

Air pollutant emissions, fuel consumption, and household air pollution were investigated in rural Hubei, central China, as a revisited evaluation of an intervention program to replace coal use by wood in gasifier stoves. Measured emission factors were comparable to the results measured two years ago when the program was initiated. Coal combustion produced significantly higher emissions of CO2, CH4, and SO2 compared with wood combustion; however, wood combustion in gasifier stoves had higher emissions of primary PM2.5 (particles with diameter less than 2.5 μm), Elemental Carbon (EC) and Organic Carbon (OC). In terms of potential impacts on climate, although the use of wood in gasifier stoves produced more black carbon (6.37 vs 910 gCO2e per day per capita from coal and wood use) and less SO2 (-684 vs -312), obvious benefits could be obtained owing to greater OC emissions (-15.4 vs -431), fewer CH4 emissions (865 vs 409) and, moreover, a reduction of CO2 emissions. The total GWC100 (Global Warming Potential over a time horizon of 100 years) would decrease by approximately 90% if coal use were replaced with renewable wood burned in gasifier stoves. However, similar levels of ambient particles and higher indoor OC and EC were found at homes using wood gasifier stoves compared to the coal-use homes. This suggests critical investigations on potential health impacts from the carbon-reduction intervention program.