The occurrence, distribution, and ecological risk of 10 quinolones (QNs) were investigated in the water and sediment samples from Baiyangdian Lake, China. The field samplings were conducted in April (dry season) and August (wet season) 2018, the results showed that QNs was extensively distributed in the Baiyangdian Lake. For the occurrence, Flumequine (FLU) and Ofloxacin (OFL) were the most detected QNs in Baiyangdian Lake. For the temporal variation, the sum concentration of QNs in water and sediment were ranged from 153 ng/L to 3093 ng/L and from 40.1 ng/g to 1475 ng/g in April, while ranged from 3.83 ng/L to 769 ng/L and from 20.3 ng/g to 373 ng/g in August. For the spatial variation, all of QNs exhibited significance difference in concentration at different sampling areas. Furthermore, PNEC plays an important role in ecological risk assessment, thus the PNECs of FLU and OFL were derived by assessment factors (AF), species sensitivity distribution (SSD), and AQUATOX model methods. The results showed that: PNECAFs, PNECSSDs, and PNECAQUATOXs were 18.7 μg/L, 196 μg/L, and 128 μg/L for FLU, respectively; and were 0.021 μg/L, 4.40 μg/L, and 3.00 μg/L for OFL, respectively. The PNECs for FLU and OFL derived by three approaches showed the rank of: PNECSSDs > PNECAQUATOXs > PNECAFs; while the risk quotients (RQs) followed the other rank of: RQSSDs < RQAQUATOXs < RQAFs. The results was indicated that the indirect ecological effects plays an important role in the derived PNECs for QNs, without considering the indirect ecological effects in natural ecosystem can lead to under-protective or over-protective PNECs (RQs) for chemicals. Therefore, AQUATOX model can be applied in deriving PNECs during the ecological risk assessment.

Litter is omnipresent in the ocean where it can be ingested by marine biota. Although ingestion of microplastics (MPs) is abundantly reported, insights into how MP can influence predator-prey interactions currently limits our understanding of the ecological impact of MPs. Here we demonstrate trophic transfer of MPs from zooplankton to benthic filter feeders, through consumption of contaminated prey (i.e. prey with ingested MP). However, predation rates of contaminated prey were significantly lower as compared to predation rates of prey that had no MPs ingested. As filter feeder clearance rates were not affected by consumption of MPs, the lower predation rates of contaminated prey appear to be primarily explained by disruption in zooplankton swimming behaviour that reduces their filtration risk. This is the first study that shows how MPs can change predator-prey interactions that are involved in the coupling between the pelagic and seabed habitat.

In compliance to European Union directives to reuse urban wastes as secondary fuels, the aim of present work was to investigate and control the environmental impact from disposal of ashes generated by combustion of a bio-solid, an olive by-product and their blend. Two waste materials were admixed with the ash and their performance as potential stabilizers was assessed. Metals and ions leached through a soil were measured.The results showed that dissolution of some alkaline substances raised the pH of water effluents, decreasing the extractability of heavy metals from the ashes. In some cases Cr and As leached reached hazardous levels. Upon addition of waste materials to ash, the concentration of Cr in liquid extracts was reduced by 35–97%, while that of Cu and As by 100%. All heavy metal values measured in the leachates were decreased to values below legislation limits. The mineralogy, the chemistry and the pH of solids involved were key factors for the retention of elements.

Samples from two reservoirs with eutrophication problems, located in Pontevedra and Ourense (Northwestern Spain), were cultured, along with a third crop from a reservoir with no problems detected in Ourense (Northwestern Spain). The samples were grown under the same conditions (with an average temperature of 21 ± 2 °C, and a 3000 lux light intensity) in triplicate, and their growth, absorbance and pH were studied. High correlation values were obtained for pH and cellular growth (R² ≥ 95%). The water from Salas showed the greatest microalgal growth (0.15 × 10⁶ cells/ml to 31.70 × 10⁶ cells/ml of Microcystis sp. for the last day of culturing) and the greatest increase in pH (5.72–9.02). In all the cultures studied here, the main species that reproduced was Microcystis sp., which can produce neurotoxins and hepatotoxins. In addition, water samples were cultured with sediments of their own reservoir and with others to observe their evolution. The sediments studied in this case were rich in biotites, which can lead phosphate to be a limiting factor for phytoplankton due to the formation and sedimentation of insoluble salts of ferric phosphate. In crops grown with sediments from the Salas reservoir, actinobacteria developed which can inhibit microalgal growth. The study of the growth of cyanobacteria and possible methods of inhibiting them directly concerns the quality of water and its ecosystems, avoiding pollution and impact on ecosystems.

The long-term contamination of soil by microplastics may pose risks that are often still not well understood, and the ecological effects of microplastics are mainly dependent on their environmental behavior in environments. This study used saturated quartz sand as a solid porous medium to study the migration and influencing factors of 40–48 μm polyethylene (PE) particles in saturated porous media. The breakthrough curves at different injection concentrations (0.3, 0.4, 0.5 mg/L), flow rates (1.0, 1.5, 2.0, 2.5 ml/L), porous medium particle sizes (1–2, 2–4 mm), ionic strengths (0, 0.01, 0.05 mol/L) and concentrations of fulvic acid (FA) (0, 5, 10 mg/L) were compared and analyzed. The Derjaguin-Landau-Verwey-Overbeek (DLVO) theory was used to more accurately explain relevant transport behaviors. The results showed that the input concentration, flow rate, and particle size can affect the migration of PE particles individually or in combination. As ionic strength increased, the repulsion between microplastics and quartz sand gradually disappeared according to DLVO theory, and their attraction gradually strengthened. As a result, fewer microplastics could penetrate the sand column and reach the water body. With the continuous addition of FA, the repulsive energy between microplastics and quartz sand rose from DLVO theory, and the migration ability of microplastics initially increased before becoming stable because of the effect of straining. In all cases, the migration ability of PE was low (C/C₀ < 0.35), and most PE particles remained in the porous media during the whole experimental periods. This study provides new insights of understanding the migration of microplastics in environment.

Recently, numerous studies concerning dye-labeled microplastic beads have reported on the end-of-life, environmental effects of microplastics because of their ubiquitous commercial usage. Less is understood about the toxicity and bioaccumulation of plastics other than microplastic beads, which can also harm the environment (e.g., fragments, fibers, foams, and films). Expanded polystyrene (EPS) is widespread in the environment owing to its many uses, however, limited research has been conducted on EPS foams. This study focuses on developing an efficient method for the preparation of micro-sized EPS foams for research purposes and compares it with previous microplastics preparation methods reported in 68 previous studies. It was demonstrated that the iced EPS block method (iced EPS block + water) generated larger quantities of smaller-sized EPS foams (20–200 and 200–500 μm) compared to the EPS + ice + water and EPS + water methods. The optimal protocol includes 1) iced EPS block preparation, 2) grinding and sieving, and 3) collecting. Additionally, it was confirmed that the iced EPS block method requires less money, labor, and time compared to previously reported methods in the literature. The method proposed in this research can assist future investigations into the environmental effects of EPS foams.

On December 31, 2019, the Chinese authorities reported to the World Health Organization (WHO) the outbreak of a new strain of coronavirus that causes a serious disease in the city of Wuhan, China. This outbreak was classified as SARS-CoV2 and is the cause of the COVID-19 disease. On March 11, 2020, the WHO declares it a Pandemic and today it is considered the greatest challenge in global health that humanity has faced since World War II and it is estimated that between 40 and 60% of the population worldwide will catch the virus. This has caused enormous challenges in countries around the world in social, economic, environmental and obviously health issues. These challenges are mainly due to the effects of the established quarantines in almost all capitals and major cities around the world, from Asia, Europe to America. However, these lockdown which began worldwide from January 23, have had a significant impact on the environment and on the air quality of cities as recently reported by NASA (National Aeronautics and Space Administration) and ESA (European Space Agency), with reductions according to them of up to 30% in some of the epicenters such as the case of Wuhan. Knowing that air pollution causes approximately 29% of lung cancer deaths, 43% of COPD deaths, and 25% of ischemic heart disease deaths, it is important to know the effects of quarantines in cities regarding air quality to take measures that favor populations and urban ecosystems when the emergency ends. Therefore, this paper describes the behavior of PM₂.₅ emissions particulate matter from the 50 most polluted capital cities in the world according to the WHO, measured before-after the start of the quarantine. Likewise, the impact at the local and global level of this emissions behavior, which averaged 12% of PM₂.₅ decrease in these cities.

Increasing levels of road noise are creating new anthropogenic soundscapes that may affect wildlife globally. Bats, which form about a third of all mammal species, are sensitive bioindicators, and may be particularly vulnerable because of their dependency on echolocation. Here we present the first controlled field experiment with free-living bats. Using a Before-After-Control-Impact phantom road experimental design, we examine the impacts of traffic noise on their activity and feeding behaviour. Disentangling the impacts of traffic noise from other co-varying exposures such as habitat quality, the experiment demonstrates a significant negative effect on the activity of each of the five, ecologically different, species (genus for Myotis spp.) examined. This suggests that the results are widely applicable. The negative effects are largely attributable to noise in the sonic spectrum, which elicited aversive responses in all bat species tested,whereas responses to ultrasoundwere restricted to a single species. Our findings demonstrate that traffic noise can affect bat activity at least 20m away from the noise source. For Pipistrellus pipistrellus and Pipistrellus pygmaeus, feeding behaviour, as well as overall activity, was negatively affected. Ecological Impact Assessments are therfore needed wherever there are significant increases in traffic flow, and not just when new roads are built. Further research is required to identify effective mitigation strategies, to delineate the zone of influence of road noise, and to assess whether there is any habituation over time.

The removal of antibiotics has attracted much attention due to their extremely high adverse impacts on the environment. However, the potential risks of degradation intermediates are seldom reported. In this work, the influence of different factors on the electro-catalytic degradation efficiency of tetracycline hydrochloride (TCH) by the prepared carbon nanotubes/agarose/indium tin oxide (CNTs/AG/ITO) electrode was investigated. Under optimal conditions (10 wt% CNTs dosage, pH = 7), the maximum degradation efficiency for TCH (10 mg L⁻¹) reached up to 96% within 30 min treatment with 4 V potential. Superoxide anions (•O₂⁻) played an important role in the electro-catalytic degradation. Totally 10 degradation intermediates were identified using HPLC-MS/MS, and the degradation pathway was proposed. Toxicities of the parent antibiotic and the identified intermediates were calculated using the ECOSAR (Ecological Structure Activity Relationship) program in EPISuite, and results showed that more toxic intermediates were generated. The maximal chronic toxicity for green algae of the intermediate increased 1439.92 times. Furthermore, antimicrobial activity was further verified by disk agar biocidal tests with Escherichia coli ATCC25922 and higher biotoxicity intermediates compared with parent compounds were confirmed to be formed. Therefore, more attention should be paid on the potential risk of degradation intermediates in the treatment of wastewater containing antibiotics.

The 2011 spill at platforms B and C of the Penglai 19-3 oil field in the Bohai Sea has been the worst oil spill accident in China. To assess long-term effects, a comprehensive monitoring program of chemical and biological variables (within a 2.2 km radius of the spill site) was conducted five years after the spill. Comparison of nutrient, Chl-a and oil concentrations in seawater, TOC, PAHs, heavy metals concentrations within the sediments, and the abundance and biomass of macrobenthic organisms to values obtained before and after the oil spill in previous studies indicate habitat recovery has occurred within the Bohai Sea following the episodic oil release. Observed elevated oil concentration in the water column and higher concentrations of two heavy metals, five PAHs, TOC, TOC/TN and lower values of δ¹³C, together with a reduction in macrobenthic biomass in near-field samples, suggest the influence of contaminants from chronic releases of oil and operational waste discharges within the vicinity of the oil platforms.