Biomass burning (BB), such as, crop field burning during the post-harvest season, emits large amounts of air pollutants (e.g., PM₂.₅) that severely impact human health. However, it is challenging to evaluate the impact of BB on PM₂.₅ due to uncertainties in the size and location of sources as well as their temporal and spatial variability. This study focused on the impacts of BB on local pollution as well as the long-range transport of PM₂.₅ in Northeast Asia resulting from a huge field BB event in Northeast China during the autumn of 2014. Air quality simulations using the Community Multiscale Air Quality (CMAQ) model were conducted in the year 2014 over the horizontal domains covering Northeast Asia, including the Japanese mainland. In the baseline simulation (Base), field BB emissions were derived from Fire INventory from NCAR (FINN) v1.5 for the year 2014. The model reasonably captured the daily mean PM₂.₅ mass concentrations, however, it underestimated concentrations in autumn around Northeast China where irregular field BB following the harvest occurred frequently. To address the underestimation of emissions from BB sources in China, another simulation with boosted BB sources from cropland area (FINN20_crop) was conducted in addition to the Base simulation. The model performance of FINN20_crop was significantly improved and showed smaller biases and higher indices of agreement between simulated and observed values in comparison to those of Base. To evaluate long-range transport of PM₂.₅ from BB sources in China towards Japan, CMAQ with brute-force method (CMAQ/BFM)-estimated BB contributions for Base and FINN20_crop cases were compared with Positive Matrix Factorization (PMF)-estimated BB contributions at Noto Peninsula in Japan. The CMAQ/BFM-estimated contributions from FINN20_crop were in greater agreement with the PMF-estimated contributions. The comparison of BB contributions estimated by the two contrasting models also indicated large underestimations in the current BB emission estimates.

Silver ions are among the predominant anthropogenic introduced pollutants in aquatic systems. As silver has effects on species at all trophic levels the community composition in aquatic habitats can be changed as a result of silver stress. The response of planktonic protists to environmental stressors is particularly important as they act both as producers and consumers in complex planktonic communities. Chrysomonad flagellates are of major interest, since this group includes heterotrophic, mixotrophic and phototrophic taxa, and therefore allows analysis of silver stress in organisms with contrasting nutritional strategies independent of a potential taxonomic bias. In a series of lab experiments, we compared the response of different trophic chrysophyte strains to low (5 μg L⁻¹), medium (10 μg L⁻¹) and high (20 μg L⁻¹) nominal Ag concentrations in combination with changes in temperature and light intensity (phototrophs), temperature and food concentration (heterotrophs), or a combination of the above settings (mixotrophs). All tested strains were negatively affected by silver in their growth rates. The phototrophic strains reacted strongly to silver stress, whereas light intensity and temperature had only minor effects on growth rates. For heterotrophic strains, high food concentration toned down the effect of silver, whereas temperatures outside the growth optimum had a combined stress effect. The mixotrophic strains reacted differently depending on whether their nutritional mode was dominated by heterotrophy or by phototrophy. The precise response pattern across all variables was uniquely different for every single species we tested. The present work contributes to a deeper understanding of the effects of environmental stressors on complex planktonic communities. It indicates that silver will negatively impact planktonic communities and may create shifts in their composition and functioning.

Volatile organic compounds (VOCs) are an important factor affecting ambient air quality, and furniture production is one of the important sources of VOC pollution. High VOC concentrations have adverse effects on the environment and worker welfare in furniture factories. In order to control VOC emissions in a furniture workshop, the VOC species and concentration distributions were examined. Qualitative analysis of VOC species was carried out by headspace gas chromatography/mass spectrometry. The results showed that VOCs from a furniture workshop were mainly 12 substances including acetate, toluene, and xylene compounds. The heights and representative positions of VOCs released during the coating process were determined, and the results showed that VOC concentrations depended on environmental and height factors. The concentration of VOCs decreased with increasing altitude and reached a maximum concentration at 0.4 m above the ground. Because the concentration of VOCs varied with temperature, humidity, air pressure, and amount of spray paint, this paper established functional relationships between VOC concentrations and temperature, humidity, air pressure, and amount of spray paint. These results provide a theoretical basis for furniture workshops to automatically monitor and control VOCs.VOCs from the furniture workshop were mainly composed of 10 substances including acetate, toluene, and xylene compounds.

Whilst numerous studies have explored the spatial patterns and underlying causes of PM₂.₅, little attention has been paid to the spatial heterogeneity of the factors affecting PM₂.₅. In this study, a geographically weighted regression (GWR) model was used to explore the strength and direction of nexus between various factors and PM₂.₅ in Chinese cities. A comprehensive interpretive framework was established, composed of 18 determinants spanning the three categories of natural conditions, socioeconomic factors, and city features. Our results indicate that PM₂.₅ concentration levels were spatially heterogeneous and markedly higher in cities in eastern China than in cities in the west of the country. Based on the results of GWR, significant spatial heterogeneity was identified in both the direction and strength of the determinants at the local scale. Among all of the natural variables, elevation was found to be statistically significant with its effects on PM₂.₅ in 95.60% of the cities and it correlated negatively with PM₂.₅ in 99.63% cities, with its effect gradually weakening from the eastern to the western parts of China. The variable of built-up areas emerged as the strongest variable amongst the socioeconomic variables studied; it maintained a positive significant relationship in cities located in the Pearl River Delta and surrounding areas, while in other cities it exhibited a negative relationship to PM₂.₅. The highest coefficients were located in cities in northeast China. As the strongest variable amongst the six landscape factors, patch density maintained a positive relationship in part of cities. While in cities in the northeast regions, patch density exhibited a negative relationship with PM₂.₅, revealing that increasing urban fragmentation was conducive to PM₂.₅ reductions in those regions. These empirical results provide a basis for the formulation of targeted and differentiated air quality improvement measures in the task of regional PM₂.₅ governances.

Microplastics (<5 mm) are distributed ubiquitously in natural environments. The majority of microplastics in aquatic environments are shown to have rough surfaces due to various weathering processes (secondary microplastics; SMP), while laboratory studies predominantly utilise pristine microplastics (primary microplastics; PMP). Here we present the results from a study comparing the chronic effects of pristine PMP and artificially weathered SMP to three different Cladoceran species (Daphnia magna, Daphnia pulex, Ceriodaphnia dubia). We assessed the impact of PMP and SMP on reproductive output using various measured parameters, including time of first brood, size of first brood, size of first three broods, cumulative number of neonates, total number of broods and terminal length of test animals. Our results show that reproductive output of all species declined in a dose-dependent manner. The No Observed Effect Concentration (NOEC) was less than the lowest tested concentration (102 p/mL) for at least one measured endpoint for all species and both PMP and SMP. Further, it was inferred that species sensitivity varied inversely with body size for most endpoints, resulting in C. dubia being the most sensitive species; and D. magna being the least sensitive species under study. In addition, PMP appeared to have greater toxic potential as compared to SMP. This study is the first to directly compare the chronic toxicity of both pristine and weathered microplastic particles on three freshwater toxicological model organisms. Our results indicate that sensitivity in reproduction and growth to microplastics may differ between species and type of microplastic exposed; highlighting the importance of using multiple species and structural types of particles.

The consumption of tonnes of anti-tubercular and other anti-microbial compounds for the control of the tuberculosis epidemic and other opportunistic diseases associated with human immunodeficiency virus presents tuberculosis-endemic countries such as South Africa, with a problem regarding the occurrence and fate of these compounds in the aquatic environment. The majority of these compounds are not readily degradable and could persist in the aquatic environment with potential detrimental effect on the aquatic microbiota ecosystem, development and dissemination of anti-microbial resistance as well as chronic toxicity in humans due to long-term exposure. This review summarises and discusses the occurrence, fate and potential adverse effects of the commonly administered anti-tubercular compounds in the aquatic environment in tuberculosis-endemic countries and South Africa in particular. It further attempts to identify information gaps in the literature regarding anti-tubercular compounds in the environment that needs further investigation so that their risk can be comprehensively assessed and impact mitigated.

Development of low-cost cathode materials for Plant-Sediment Microbial Fuel Cells (P-SMFCs) has gained increasing interest, due to improved performance levels in terms of power and pollutant removal. A novel low cost three-dimensional cathode prepared by simple three-step strategy with growth of Co₃O₄ in-situ biofilm was successfully prepared. Different cathodes were applied to the six parallel P-SMFCs systems (reactor: R1-R6), such as graphite felt (GF), Pt/C, GF@Co₃O₄ (non-bonding Co₃O₄ nanowires on GF), GF@SG-Co₃O₄ (using argon as shielding gas (SG)). Its performances (R1, R2: control groups) were evaluated by electricity generation and Cr(VI) reduction at initial cadmium concentrations (4.97, 10.29 and 21.16 mg L⁻¹). A significant Cr(VI) removal efficiency of 99.76%, maximum power density of 75.12 ± 2.90 mW m⁻² and Cr(VI) adsorption capacity of 1.67 mg g⁻¹ were obtained at initial Cr(VI) concentration of 21.16 mg L⁻¹ with non-bonding GF@Co₃O₄ and bio-GF@SG-Co₃O₄ as cathodes. This indicated that these two materials were better than others (GF, Pt/C and GF@Co₃O₄) as cathodes. Characterization analysis including scanning electron microscope (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Polarization curve, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) showed that high current generation Cr(VI) removal mainly attributed to transportation of plants, adsorption of bio-cathode, formation of a relatively high concentration region and abundant oxygen vacancies of GF@SG-Co₃O₄. The results show that P-SMFCs with GF@SG-Co₃O₄ cathode may be a potentially novel approach for remediating Cr(VI) contaminated waster or soil.

In recent years, ozone pollution has become more and more serious in China. Several epidemiological studies have demonstrated the correlation between short-term ozone exposure and several health risks including all-cause mortality, cardiovascular mortality, and respiratory mortality. In this study, the daily ozone exposure levels with 10 km × 10 km resolution were estimated based on satellite data derived from Ozone Monitoring Instrument (OMI) and the monitoring data. The health impacts for potential decrease in the daily ozone concentration and the corresponding economic benefits in 2016 were estimated by applying the environmental Benefits Mapping and Analysis Program-Community Edition (BenMAP-CE) model. By reducing the daily maximum 8-h average concentration of ozone to 100 μg/m³, the estimated avoided all-cause mortalities were 120 × 10³ (95% confidence interval (CI): 67 × 10³, 160 × 10³) cases and the correspondingly economic benefits ranged from 36 to 64 billion CNY using amended human capital (AHC) and willingness to pay (WTP) method in 2016. If the daily maximum 8-h average concentration of ozone were rolled back to 70 μg/m³, the estimated avoided all-cause mortalities were 160 × 10³ (95% CI: 98 × 10³, 230 × 10³) cases and economic benefits ranged from 54 to 95 billion CNY based on AHC and WTP methods.

This study aimed to evaluate and qualify field-based potential risks of seven neonicotinoid and phenylpyrazole (fipronil) insecticides on aquatic invertebrates, including estuary-resident marine crustaceans. One hundred and ninety-three estuarine water samples, with salinity ranging from 0.5 to 32.7, were collected from four estuarine sites in the Seto Inland Sea of Japan, in 2015–2018 and the insecticide levels were measured. Five neonicotinoid and fipronil insecticides were successfully identified, and their occurrence varied temporally. Marine crustaceans were simultaneously harvested every month from one of the estuarine water sampling sites in 2015–2017. Three predominant crustacean species, kuruma prawn (Penaeus japonicus), sand shrimp (Crangon uritai), and mysid (Neomysis awatschensis), were captured and their seasonal presence was species independent. A 96-h laboratory toxicity study with the insecticides using kuruma prawn, sand shrimp, and a surrogate mysid species (Americamysis bahia) indicated that fipronil exerted the highest toxicity to the three crustaceans. Using both toxicity data and insecticide occurrence in estuarine water (salinity ≥10, n = 169), the potential risks on the three marine crustaceans were quantified by calculating the proportion of mixture toxicity effects (Pₘᵢₓ). The Pₘᵢₓ of seven neonicotinoids on the crustaceans was less than 0.8%, which is likely to be too low to indicate adverse effects caused by the insecticides. However, short temporal detection of fipronil (exclusively in June and July) significantly affected the Pₘᵢₓ, which presented the maximal Pₘᵢₓ values of 21%, 3.4%, and 72% for kuruma prawn, sand shrimp, and mysid, respectively, indicating a significant effect on the organisms. As for estuarine water (salinity <10), some water samples contained imidacloprid and fipronil exceeding the freshwater benchmarks for aquatic invertebrates. The present study provides novel insights into the seasonally varying risks of insecticides to estuarine crustaceans and highlights the importance of considering whether ecological risk periods coincide with crustacean presence.

Jumping on the bed is a favorite behavior of children; however, no study has investigated the increased air pollutants resulting from jumping on the bed. Therefore, we aimed to investigate the elevated concentrations of particulate matter (PM) and bioaerosols from jumping on the bed and making the bed. Simulation of jumping on the bed and making the bed was performed at sixty schoolchildren's houses in Taiwan. PM10, PM2.5, PM1 (PM with aerodynamic diameter less than 10, 2.5, and 1 μm, respectively) and airborne bacteria, fungi and endotoxin concentrations were simultaneously measured over simulation and background periods. Our results show the increase of PM10, PM2.5, PM1, airborne bacteria and fungi through the behavior of jumping on the bed (by 414 μg m-3, 353 μg m-3, 349 μg m-3, 6569 CFU m-3 and 978 CFU m-3, respectively). When making the bed, the PM10, PM2.5, PM1, airborne bacteria and fungi also significantly increased by 4.69 μg m-3, 4.09 μg m-3, 4.15 μg m-3, 8569 CFU m-3, and 779 CFU m-3, respectively. Airborne endotoxin concentrations significantly increased by 21.76 EU m-3 following jumping on the bed and making the bed. Moreover, when jumping on the bed, higher PM2.5 and PM1 concentrations in houses with furry pets rather than no furry pets, and less airborne fungi in apartments than in townhouses were found. For making the bed, lower airborne fungi was found in houses using essential oils rather than no essential oils using. The airborne endotoxin concentrations were positively associated with furry pets and smokers in the homes and negatively correlated to the home with window opening with a statistical significance during the periods of jumping on the bed and making the bed. In conclusion, significant increases of PM and bioaerosols during jumping on the bed and making the bed may need to be concerned.