Urban activities intensify air pollution by increasing the amount of particulate matter (PM). The trees collect PM by adsorption on the leaf surface and simultaneously absorb inorganic components. In this research, we investigated the potential of the black pine as bioindicator of road traffic emissions in Cluj-Napoca (Romania). We defined three sites types with different exposure to the road traffic (streets, outskirts, parks) and a control site far from the city. We quantified 17 inorganic components (Al, B, Ba, Ca, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, Sr, Zn) by MP-AES (microwave-plasma atomic emission spectroscopy) technique in the one-year-old needles and we identified the best candidates for biomonitoring purposes. The concentration of Ba, Cr, Cu and Fe showed the most sensitive variations with the road traffic intensity. While in the streets the Ba, Cu and Fe increased by 2.8–3.5 times in relation to the control site, the Cr varied in the highest degree exhibiting ratios of 2.2 (parks), 3.3 (outskirts) and 6.3 (streets). The success of these elements lies in several characteristics: they are closely related to non-exhaust emissions, they are readily absorbed through the leaves rather than the roots, and they tend to accumulate in the needles instead of being relocated to other organs. The street maintenance activities caused considerable accumulation of Na in the trees from the roadsides, but had no impact over the trees from the parks. The elements originating mainly in the re-suspended urban dust (Ni, Pb, Sr) equally affected the pines from the streets and parks.

Zearalenone (ZEN), a mycotoxin with endocrine disruptive activity and oxidative stress generating ability, has been a worldwide environmental concern for its prevalence and persistency. However, the long-term effect of ZEN on aging process is not fully elucidated. Thus, the present study applied the Caenorhabditis elegans model to investigate the aging-related toxic effect and possible underlying mechanisms under prolonged and chronic ZEN exposure. Our results showed that locomotive behaviors significantly decreased in ZEN (0.3, 1.25, 5, 10, 50 μM) treated C. elegans. In addition, lifespan and aging markers including pharyngeal pumping and lipofuscin were also adversely affected by ZEN (50 μM). Furthermore, ZEN (50 μM) increased ROS level and downregulated antioxidant genes resulted from inhibition of nuclear DAF-16 translocation in aged C. elegans, which was further confirmed by more significant aging-related defects observed in ZEN treated daf-16 mutant. In conclusion, our findings suggest that the aging process and aging-related decline were induced by long-term exposure of ZEN in C. elegans, which is associated with oxidative stress, inhibition of antioxidant defense, and transcription factor DAF-16/FOXO.

Aquatic hyphomycetes (AHs), a group of saprotrophic fungi adapted to submerged leaf litter, play key functional roles in stream ecosystems as decomposers and food source for higher trophic levels. Fungicides, controlling fungal pathogens, target evolutionary conserved molecular processes in fungi and contaminate streams via their use in agricultural and urban landscapes. Thus fungicides pose a risk to AHs and the functions they provide. To investigate the impacts of fungicide exposure on the composition and functioning of AH communities, we exposed four AH species in monocultures and mixed cultures to increasing fungicide concentrations (0, 5, 50, 500, and 2500 μg/L). We assessed the biomass of each species via quantitative real-time PCR. Moreover, leaf decomposition was investigated. In monocultures, none of the species was affected at environmentally relevant fungicide levels (5 and 50 μg/L). The two most tolerant species were able to colonize and decompose leaves even at very high fungicide levels (≥500 μg/L), although less efficiently. In mixed cultures, changes in leaf decomposition reflected the response pattern of the species most tolerant in monocultures. Accordingly, the decomposition process may be safeguarded by tolerant species in combination with functional redundancy. In all fungicide treatments, however, sensitive species were displaced and interactions between fungi changed from complementarity to competition. As AH community composition determines leaves’ nutritional quality for consumers, the data suggest that fungicide exposures rather induce bottom-up effects in food webs than impairments in leaf decomposition.

Organophosphate esters (OPEs) pose increasing concerns for their widespread distribution in soil environments and potential threat to human health. In this study, we investigated the occurrence and associated risks of seven OPEs in surface soils and the potential influence of human activities on soil OPE contamination in a heavily urbanized region of the Yangtze River Delta in Eastern China. All target OPEs were detected in the soil samples (100% of samples) reflecting their widespread distribution in the study region. The total OPE concentration (the sum of the seven OPEs) ranged from 162.7 to 986.0 ng/g on a dry weight basis, with a mean value of 469.3 ± 178.6 ng/g. Tris (2-butoxyethyl) phosphate was the main compound, accounting for 67–78% of the total OPE concentration. Ecological risk assessment showed that tris(2-chloroisopropyl) phosphate, tris(2,3-dichloropropyl) phosphate, tris(2-butoxyethyl) phosphate, and tris(2-ethylhexyl) phosphate posed a medium potential risk to terrestrial biota (0.1 < risk quotient <1). The human exposure estimation showed insignificant risks to local population. Redundancy analysis revealed that the individual and total OPE contaminations were positively correlated with human activity parameters. The total OPE concentrations were positively correlated to population density (R² = 0.38, P < 0.001), and urban land use percentage (R² = 0.39, P < 0.001), while negatively correlated to forest land use percentage (R² = 0.59, P < 0.001), suggesting a significant contribution of human disturbance to OPE pollution. These results can facilitate OPE contamination control and promote sustainable soil management in urbanized and industrialized regions.

Subsurface wastewater infiltration systems (SWISs) have been widely used to treat rural domestic sewage. However, the low nitrogen removal and severe clogging problem always restrict the sustainability of SWISs for wastewater treatment. This study investigated the effects of aeration and biochar on the accumulation of nutrients and dissolved organic matter (DOM) in the substrate of loess soil-based SWISs for understanding the accumulation characteristics of DOM and the enhanced decontamination mechanism. The results showed that biochar addition could not improve the accumulation of nitrogen and phosphorus in the substrate, but could enhance denitrification (22%) via providing sufficient carbon for microorganisms. Moreover, the accumulation of organic matter in the substrate was also greatly affected. The DOM concentration of System D in the 40–60 cm layer reached 85.76 mg L⁻¹, which indicated that biochar could release abundant DOM. Substrate DOM mainly contained humic acid-like and tryptophan-like substances. Moreover, the refractory macromolecular DOM components with high aromaticity and humification were found in the substrate below 60 cm of systems with biochar addition. This may be related to the DOM released by biochar and the extracellular polymeric substance (EPS) produced by microorganisms. It may affect the sustainability of the substrate to a certain extent, but fortunately that intermittent aeration could reduce this adverse effect. This research could provide new insights for preventing clogging and useful guidance for improving wastewater treatment performance in SWISs.

Recent studies have indicated that Galleria mellonella larvae ingest polyethylene films and the degradation mechanism could inspire biotechnological exploitation for degrading plastic to eliminate global pollution from plastic waste. In this study, we tested the chemical compositions of masticated and ingested different plastic types by G. mellonella. High throughput sequencing of 16S rRNA gene was used to characterize the alteration of the microbial communities derived from salivary glands, gut contents and whole G. mellonella larvae. Our results indicated that G. mellonella is able to masticate polyethylene (PE), expanded polystyrene (EPS) and polypropylene (PP) and convert it to small particles with very large and chemically modified surfaces. The characteristics of the polymer affect the rate of damage. Formation of functional carbonyl groups on the appearance of oxidized metabolic intermediates of polyolefins in the frass samples observed. We found that the mastication of EPS, PP or PE could significantly alter the microbial composition in the gut content while it did not appear to influence the salivary glands microbial community. Representatives of Desulfovibrio vulgaris and Enterobacter grew with the PE diet while mastication of polystyrene and polypropylene increased the abundance of Enterococcus. The evaluation of bacterial communities in whole larvae confirmed the obtained result and additionally showed that the abundance of Paenibacillus, Corynebacterium and Commamonadaceae increased by Styrofoam (EPS) consumption.

This study investigates changes in air quality conditions during the restricted COVID-19 lockdown period in 2020 across 21 metropolitan areas in the Middle East and how these relate to surface urban heat island (SUHI) characteristics. Based on satellite observations of atmospheric gases from Sentinel-5, results indicate significant reductions in the levels of atmospheric pollutants, particularly nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and carbon monoxide (CO). Air quality improved significantly during the middle phases of the lockdown (April and May), especially in small metropolitan cities like Amman, Beirut, and Jeddah, while it was less significant in “mega” cities like Cairo, Tehran, and Istanbul. For example, the concentrations of NO₂ in Amman, Beirut, and Jeddah decreased by −56.6%, −43.4%, and −32.3%, respectively, during April 2020, compared to April 2019. Rather, there was a small decrease in NO₂ levels in megacities like Tehran (−0.9%) and Cairo (−3.1%). Notably, during the lockdown period, there was a decrease in the mean intensity of nighttime SUHI, while the mean intensity of daytime SUHI experienced either an increase or a slight decrease across these locations. Together with the Gulf metropolitans (e.g. Kuwait, Dubai, and Muscat), the megacities (e.g. Tehran, Ankara, and Istanbul) exhibited anomalous increases in the intensity of daytime SUHI, which may exceed 2 °C. Statistical relationships were established to explore the association between changes in the mean intensity and the hotspot area in each metropolitan location during the lockdown. The findings indicate that the mean intensity of SUHI and the spatial extension of hotspot areas within each metropolitan had a statistically significant negative relationship, with Pearson's r values generally exceeding - 0.55, especially for daytime SUHI. This negative dependency was evident for both daytime and nighttime SUHI during all months of the lockdown. Our findings demonstrate that the decrease in primary pollutant levels during the lockdown contributed to the decrease in the intensity of nighttime SUHIs in the Middle East, especially in April and May. Changes in the characteristics of SUHIs during the lockdown period should be interpreted in the context of long-term climate change, rather than just the consequence of restrictive measures. This is simply because short-term air quality improvements were insufficient to generate meaningful changes in the region's urban climate.

High delicate particulate matter (PM₂.₅) concentration can seriously reduce air quality, destroy the environment, and even jeopardize human health. Accordingly, accurate prediction for PM₂.₅ plays a vital role in taking precautions against upcoming air ambient pollution incidents. However, due to the disturbance of seasonal and nonlinear characteristics in the raw series, pronounced forecasts are confronted with tremendous handicaps, even though for seasonal grey prediction models in the preceding researches. A novel seasonal nonlinear grey model is initially designed to address such issues by integrating the seasonal adjustment factor, the conventional Weibull Bernoulli grey model, and the cultural algorithm, simultaneously depicting the seasonality and nonlinearity of the original data. Experimental results from PM₂.₅ forecasting of four major cities (Shanghai, Nanjing, Hangzhou, and Hefei) in the YRD validate that the proposed model can obtain more accurate predictive results and stronger robustness, in comparison with grey prediction models (SNGBM(1,1) and SGM(1,1)), conventional econometric technology (SARIMA), and machine learning methods (LSSVM and BPNN) by employing accuracy levels. Finally, the future PM₂.₅ concentration is forecasted from 2020 to 2022 using the proposed model, which provides early warning information for policy-makers to develop PM₂.₅ alleviation strategies.

Polycyclic aromatic hydrocarbons (PAHs) and certain ingredients in personal care products, such as parabens, bisphenols, triclosan and phthalate metabolites, have become ubiquitous in the world. Concerns of human exposure to these pollutants have increased during recent years because of various adverse health effects of these chemicals. Multiple compounds including parabens, bisphenols, triclosan, phthalate metabolites (mPAEs) and hydroxyl PAHs (OH-PAHs) in urine samples from Guangzhou were determined simultaneously to identify the human exposure pathways without external exposure data combined with data analysis, and the toxicants posed the highest risk to human health were screened in the present study. The detection frequencies for the chemicals exceeded 90%. Among the contaminants, mPAEs showed the highest concentrations, followed by OH-PAHs, with triclosan present at the lowest concentrations. Mono-n-butyl phthalate, methylparaben, bisphenol A, and hydroxynaphthalene represented the most abundant mPAE, parabens, bisphenol, and OH-PAH compounds, respectively. The present PAHs are mainly exposed to human through inhalation, while the chemicals added to personal care products are mainly exposed to human through oral intake and dermal contact. The urine samples from suburban subjects showed significantly higher OH-PAH levels than the urine samples from urban subjects, and females had lower OH-PAH levels than males. Urinary concentrations of the analyzed contaminants were significantly correlated with age, body mass index, residence time, as well as the frequencies of alcohol consumption and swimming. Risk assessments based on Monte Carlo simulation indicated that approximately 30% of the subjects suffered non-carcinogenic risks from mPAEs and OH-PAHs, with mPAEs accounting for 89% of the total risk.

In this study, the biodegradation of endocrine-disrupting chemicals (EDCs) (namely the natural and synthetic estrogens 17β-estradiol (E2) and 17α-ethinylestradiol (EE2), respectively) was assessed in an aerobic granular sludge (AGS) sequencing batch reactor (SBR) treating simulated domestic sewage. To better understand the fate of these compounds, their concentrations were determined in both liquid and solid (biomass) samples. Throughout the operation of the reactor, subjected to alternating anaerobic and aerated conditions, the removal of the hormones, both present in the influent at a concentration of 20 μg L⁻¹, amounted to 99% (for E2) and 93% (for EE2), with the latter showing higher resistance to biodegradation. Through yeast estrogen screen assays, an average moderate residual estrogenic activity (0.09 μg L⁻¹ EQ-E2) was found in the samples analysed. E2 and EE2 profiles over the SBR cycle suggest a rapid initial adsorption of these compounds on the granular biomass occurring anaerobically, followed by biodegradation under aeration. A possible sequence of steps for the removal of the micropollutants, including the key microbial players, was proposed. Besides the good capability of the AGS on EDCs removal, the results revealed high removal efficiencies (>90%) of COD, ammonium and phosphate. Most of the incoming organics (>80%) were consumed under anaerobic conditions, when phosphate was released (75.2 mgP L⁻¹). Nitrification and phosphate uptake took place along the aeration phase, with effluent ammonium and phosphate levels around 2 mg L⁻¹. Although nitrite accumulation took place over the cycle, nitrate consisted of the main oxidized nitrogen form in the effluent. The specific ammonium and phosphate uptake rates attained in the SBR were found to be 3.3 mgNH₄⁺-N gVSS⁻¹.h⁻¹ and 6.7 mgPO₄³⁻-P gVSS⁻¹ h⁻¹, respectively, while the specific denitrification rate corresponded to 1.0 mgNOₓ⁻-N gVSS⁻¹ h⁻¹.