This study improves traditional PM₂.₅ estimation models by combining an hourly aerosol optical depth from the Advanced Himawari Imager onboard Himawari-8 with a newly introduced predictor to estimate hourly PM₂.₅ concentrations in the Beijing–Tianjin–Hebei (BTH) region from November 1, 2018 to October 31, 2019. The new predictor is an hourly PM₂.₅ forecasting product from the Model of Aerosol Species IN the Global AtmospheRe (MASINGAR). Comparative experiments were conducted by utilizing three extensively used regression models, namely, multiple linear regression (MLR), geographically weighted regression (GWR), and linear mixed effects (LME). A ten-fold cross validation (CV) demonstrated that the MASINGAR product significantly improved the performances of these models. The introduced product increased the model’s determination coefficients (from 0.316 to 0.379 for MLR, from 0.393 to 0.445 for GWR, and from 0.718 to 0.765 for LME), decreased their root mean square errors (from 38.2 μg/m³ to 36.4 μg/m³ for MLR, from 36.0 μg/m³ to 34.4 μg/m³ for GWR, and from 24.5 μg/m³ to 22.4 μg/m³ for LME) and mean absolute errors (from 25.2 μg/m³ to 23.3 μg/m³ for MLR, from 23.5 μg/m³ to 21.8 μg/m³ for GWR, and from 15.2 μg/m³ to 13.7 μg/m³ for LME). Then, a well-trained LME model was utilized to estimate the spatial distributions of hourly PM₂.₅ concentrations. Highly polluted localities were clustered in the central and southern areas of the BTH region, and the least polluted area was in northwestern Hebei. Seasonal PM₂.₅ levels averaged from the hourly estimations exhibited the highest concentrations (55.4 ± 56.8 μg/m³) in the winter and lowest concentrations (25.1 ± 18.2 μg/m³) in the summer.Introducing the PM₂.₅ products from MASINGAR can significantly improve the performance of traditional models for surface PM₂.₅ estimations by 7–20%.

Globally, the Coronavirus disease (COVID-19) outbreak is linked with air pollution of both indoor and outdoor environments and co-morbidities conditions of human beings. To find out the risk factor zones associated with Coronavirus disease among under-five children using pre-existing morbidity conditions and indoor air pollution (IAP) environmental factors and also with current fatality and recovery rate of COVID-19 disease in India. Data was utilized from the 4th round of the National Family Health Survey (NFHS), 2015–16, and from the Ministry of Health and Family Welfare (MoHFW) on 18th May 2020. Mean, standard deviation, and Z-score statistical methods have been employed to find out the risk factor zones i.e. to execute the objective. Findings of this study are, the states and UTs which have more likely to very higher to higher risk factors or zones of Coronavirus disease (COVID-19) are Mizoram (1.4), Meghalaya (1.27), Uttarakhand (0.92), West Bengal (0.73), Uttar Pradesh (0.66), Jammu and Kashmir (0.44), Odisha (0.33), Madhya Pradesh (0.21), Jharkhand (0.20), Bihar (0.19), Maharashtra (0.16 risk score), compared to UTs like Assam (-0.12), Rajasthan (-0.13), Goa (-0.14), Manipur (-0.17), Chandigarh (-0.19), Haryana (-0.22), Delhi (-0.27) have moderate risk factors of COVID-19, and the states and UTs like Daman and Diu (-1.18), Sikkim (-0.98), Andaman and Nicobar Islands (-0.84), Kerala (-0.69), Dadra and Nagar Haveli (-0.68), Arunachal Pradesh (0.-53), Karnataka (-0.42), and Nagaland (-0.36) have very low-risk zones of COVID-19 deaths. From a research viewpoint, there is a prerequisite need for epidemiological studies to investigate the connection between indoor air pollution and pre-existing morbidity which are associated with COVID-19. Well-built public health measures, including rapidly searching in high focus areas and testing of COVID-19, should be performed in vulnerable areas of COVID-19.

The exposure risk of metal-based nanoparticles (NPs) to marine organisms and related food safety have attracted increasing attention, but the actual concentrations of these NPs in seawater and marine organisms are unknown. In this work, single particle inductively coupled plasma-mass spectrometry (spICP-MS) was used to quantify the concentrations and size distributions of NPs in different marine mollusks (oysters, mussels, scallops, clams, and ark shells) from an offshore aquaculture farm. Results showed that Ti, Cu, Zn, and Ag bearing NPs were detected in all the five mollusks with the mean sizes at 65.4–70.9, 72.2–89.6, 97.8–108.3, and 42.9–51.0 nm, respectively. The particle concentrations of Ti, Cu, Zn, and Ag bearing NPs in all mollusks (0.88–3.26 × 10⁷ particles/g fresh weight) were much higher than that in the seawater (0.46–0.79 × 10⁷ particles/mL), suggesting bio-accumulation of NPs. For all the five mollusks, Ag bearing NPs had the highest number-based bioconcentration factors (NBCFs) in all the tested NPs due to the smallest mean size of Ag bearing NPs in seawater (30.5 nm). In addition, the clams exhibited the lowest NBCFs of the four NPs than other mollusks. All four NPs were mainly accumulated in the gill and digestive gland, and could transfer to adductor muscle of all mollusks. Although all the four metals (Ti, Cu, Zn, Ag) in mollusks were safe for human consumption by the estimated daily intake (EDI) analysis, the risk of NPs remaining in the mollusks should be further considered when evaluating the toxicity of metals for human health. The findings could improve our understanding on the distribution and health risk of NPs in marine mollusks under offshore aquaculture.

Growing evidence suggests that anthropogenic noise has deleterious effects on the behavior and physiology of free-living animals. These effects may be particularly pronounced early in life, when developmental trajectories are sensitive to stressors, yet studies investigating developmental effects of noise exposure in free-living populations remain scarce. To elucidate the effects of noise exposure during development, we examined whether noise exposure is associated with shorter telomeres, duller carotenoid-based coloration and reduced body mass in nestlings of a common urban bird, the great tit (Parus major). We also assessed how the noise environment is related to reproductive success. We obtained long-term measurements of the noise environment, over a ∼24-h period, and characterized both the amplitude (measured by LAₑq, LA₉₀, LA₁₀, LAₘₐₓ) and variance in noise levels, since more stochastic, as well as louder, noise regimes might be more likely to induce stress. In our urban population, noise levels varied substantially, with louder, but less variable, noise characteristic of areas adjacent to a highway. Noise levels were also highly repeatable, suggesting that individuals experience consistent differences in noise exposure. The amplitude of noise near nest boxes was associated with shorter telomeres among smaller, but not larger, brood members. In addition, carotenoid chroma and hue were positively associated with variance in average and maximum noise levels, and average reflectance was negatively associated with variance in background noise. Independent of noise, hue was positively related to telomere length. Nestling mass and reproductive success were unaffected by noise exposure. Results indicate that multiple dimensions of the noise environment, or factors associated with the noise environment, could affect the phenotype of developing organisms, that noise exposure, or correlated variables, might have the strongest effects on sensitive groups of individuals, and that carotenoid hue could serve as a signal of early-life telomere length.

Marine animals often accumulate various harmful substances through the foods they ingest. The bioaccumulation levels of these harmful substances are affected by the degrees of pollution in the food and of biomagnification; however, which of these sources is more important is not well-investigated for mercury (Hg) bioaccumulation. Here we addressed this issue in fishes that inhabit the waters around Minamata Bay, located off the west coast of Kyushu Island in Kumamoto Prefecture, Japan. The total Hg concentration (hereafter [THg]) and carbon and nitrogen stable isotope ratios (δ¹³C and δ¹⁵N) were analyzed in the muscle tissue of 10 fish species, of which more than five individuals were caught by gillnet. Except one species, each was separated into two trophic groups with respective lower and higher δ¹³C values ranging from −17‰ to −16‰ and −15‰ to −14‰, which suggested that the fishes depended more on either phytoplankton- and microphytobenthos-derived foods (i.e., pelagic and benthic trophic pathways), respectively. Linear mixed effects models showed that the Hg levels were significantly associated with both δ¹⁵N and the differences in the trophic groups. [THg] increased with δ¹⁵N (i.e., indicative of higher trophic levels), but the slopes did not differ between the two trophic groups. [THg] was significantly higher in the group with higher δ¹³C values than in those with lower δ¹³C values. The effect size from marginal R squared (R²) values showed that the variation in [THg] was strongly ascribed to the trophic group difference rather than δ¹⁵N. These results suggest that the substantial Hg bioaccumulation in the fishes of Minamata Bay is mainly an effect of ingesting the microphytobenthos-derived foods that contain Hg, and that the subsequent biomagnification is secondary.

Heavy metals have been found in increasing concentrations in the aquatic environment. Fishes exposed to such metals have altered gene expression, serum profiles, tissue histology and bioindices that serve as overall health biomarkers. The heavy metals (Ni, Cd, and Cr) accumulated in water and fish tissues, were beyond the permissible limits defined by the Central Pollution Control Board/World Health Organization. Metallothionein (MT) and glutathione peroxidase (GPX) genes expression patterns highlighted the metal-specific exposure of fish. An increased fold change of genes against beta-actin serves as a potential feature for toxicity. Metal toxicity is also reflected by an increased level of digestive enzymes (amylase and lipase) in the serum and alterations in values of reproductive hormones (11-Ketotestosterone and progesterone). Total serum bilirubin attribute to the liver and biliary tract disease in fishes. Histopathological studies show cellular degeneration, breakage, vacuolization signifying the chronic stress.

Although association between polycyclic aromatic hydrocarbons (PAHs) exposure and mitochondrial DNA copy number (mtDNAcn) was researched by traditional linear model extensively, most of these studies analyzed independent effect of each PAHs metabolite and adjust for the confounding other metabolites concomitantly, without considering others interactions. As a complex organic pollutant, a reasonable statistical method is needed to study toxic effects of PAHs.Therefore, we aimed to conduct a novel statistical approach, Bayesian Kernel Machine Regression (BKMR), to explore the effect of PAHs exposure on mtDNAcn among coke oven workers. In this cross-sectional study, the concentrations urinary of PAHs metabolites were measured using high performance liquid chromatography mass spectrometry (HPLC-MS). The mtDNAcn was measured using real-time quantitative polymerase chain reaction (RT-PCR) in peripheral blood of 696 Chinese coke oven workers. The relationship of urinary of PAHs metabolites and mtDNAcn were evaluated by BKMR model. And the results showed a significant negative effect of PAHs metabolites on mtDNAcn when PAHs metabolites concentrations were all above 35th percentile compared to the median and the statistically significant negative single-exposure effect of 2-OHNAP and 2-OHPHE on mtDNAcn when all of the other PAHs are fixed at a particular threshold (25th, 50th, 75th percentile). The changes in log 2-OHNAP and 2-OHPHE from the 25th to the 75th percentile when other PAHs metabolites were at the 50th percentile were associated with change in mtDNAcn of −0.082 (−0.021, −0.124) and −0.048 (−0.021, −0.090) respectively. And evidence of a linear effect of urinary 2-OHNAP and 2-OHPHE were found. Finally, our findings suggested that PAHs cumulative exposures and particularly single-exposure of 2-OHNAP and 2-OHPHE might compromise mitochondrial function by decreasing mtDNAcn in Chinese coke oven workers.

2,6-Dimethylphenol (2,6-DMP), an important chemical intermediate and the monomer of plastic polyphenylene oxide, is widely used in chemical and plastics industry. However, the pollution problem of 2,6-DMP residues is becoming increasingly serious, which is harmful to some aquatic animals. Microbial degradation provided an effective approach to eliminate DMPs in nature, which is considered as a prospective way to remediate DMPs-contaminated environments. But the 2,6-DMP-degrading bacteria is not available and the molecular mechanism of 2,6-DMP degradation is unclear as well. Here, a 2,6-DMP-degrading bacterium named B5-4 was isolated and identified as Mycobacterium neoaurum. M. neoaurum B5-4 could utilize 2,6-DMP as the sole carbon source for growth. Furthermore, M. neoaurum B5-4 could degrade 2,6-DMP with concentrations ranging from 1 to 500 mg L⁻¹. Six intermediate metabolites of 2,6-DMP were identified and a metabolic pathway of 2,6-DMP in M. neoaurum B5-4 was proposed, in which 2,6-DMP was initially converted to 2,6-dimethyl-hydroquinone and 2,6-dimethyl-3-hydroxy-hydroquinone by two consecutive hydroxylations at C-4 and γ position; 2,6-dimethyl-3-hydroxy-hydroquinone was then subjected to aromatic ring ortho-cleavage to produce 2,4-dimethyl-3-hydroxymuconic acid, which was further transformed to citraconate, and subsequently into TCA cycle. In addition, toxicity bioassay of 2,6-DMP in water using zebrafish indicates that 2,6-DMP is toxic to zebrafish and M. neoaurum B5-4 could effectively eliminate 2,6-DMP in water to protect zebrafish from 2,6-DMP-induced death. This work provides a potential strain for bioremediation of 2,6-DMP-contaminated environments and lays a foundation for elucidating the molecular mechanism and genetic determinants of 2,6-DMP degradation.

Recently it was demonstrated that mealworm (Tenebrio molitor) larvae consume and biodegrade polystyrene. Thus, in this study a breeding investigation with various types of polystyrene was performed to follow the changes in the gut microbiome diversity. Polystyrene used for packaging purposes (PSp) and expanded polystyrene (EPS) were perceived as more favorable and attacked more frequently by mealworms compared to raw polystyrene (PS) and material commercially available for parcels (PSp). Although our studies showed that larvae could bite and chew selected materials, they are not able to degrade and use them for consumption purposes. In a next-generation sequencing experiment, among all samples, seven classes, Gammaproteobacteria, Bacilli, Clostridia, Acidobacteria, Actinobacteria, Alphaproteobacteria and Flavobacteria, were indicated as the most abundant, whereas the predominant genera were Enterobacter, Lactococcus and Enterococcus. Additionally, we isolated three bacteria strains able to use diverse types of bioplastic as a sole carbon source. The strains with biodegradable activity against bioplastic were identified as species of the genera Klebsiella, Pseudomonas and Serratia. The presence of a bacterial strain able to degrade bioplastic may suggest a potential niche for further investigations.

The presence of polystyrene (PS) waste increases constantly. Styrofoam, the most popular form of PS, is one of the major plastic pollutants in the environment. An efficient and environmentally friendly method of PS recycling is still needed. The biodegradation of PS by insects has been presented by researchers as a promising alternative to chemical, mechanical and thermal methods. The main aim of this study was to assess the survival, growth, and development of yellow mealworms (the larvae of Tenebrio molitor) fed with PS to determine if the insects are able to use PS as a source of mass and energy. The Dynamic Energy Budget (DEB) model was used to analyze the effects of food type on the growth trajectory and metabolism of tested organisms. We investigated five possible modes of influence of PS diet on DEB model parameters including a decrease of food availability, an increase in somatic maintenance power, an increase in costs for structure, allocation of energy, and a decrease in somatic maintenance power. Our results show that changes in the development of larvae fed with PS are mainly caused by a decrease in reserves density and reaction of the organism to the insufficient food supply. The inability or difficulty in completing the life cycle of T. molitor larvae fed with PS raises doubts about the use of mealworms as an effective technology for utilizing polystyrene.