We evaluated the effect of lead (Pb) abatement measures in Croatia on blood lead (BPb) concentrations, and delta-aminolevulinic acid dehydratase (ALAD) activity in blood, as a sensitive indicator of early Pb effect. Data on BPb and ALAD activity were obtained from 829 Croatian men (19–64 years of age), with no known occupational exposure to metals. Data obtained in 2008–2009, after the ban of leaded gasoline in Croatia in 2006, were compared with similar data collected in 1981 and 1989, when the concentration of Pb in gasoline was 0.6 g/L. Our results showed a highly significant (p < 0.001) decrease in median BPb from 114.5 (range, 46.0–275.0) μg/L in 1981/1989 to 30.3 (range, 3.2–140.8) μg/L in 2008–2009 and an increase in median ALAD activity from 49.8 (range, 24.9–79.4) EU in 1981/1989 to 60.9 (range, 35.8–84.0) EU in 2008–2009. Individual factors influencing BPb values were, in the order of decreasing importance, Pb in ambient air (APb), alcohol consumption, age, and smoking. Increased ALAD activity was significantly associated with the decrease of APb, alcohol consumption, and smoking. These results show that lead abatement measures had a positive impact on both BPb concentrations (73.5 % decrease) and the activity of ALAD (22.1 % increase) in general population. Our results contribute to growing evidence that ALAD activity may be used as one of the earliest and sensitive diagnostic biomarkers of low-level Pb exposure.

For effective microbe-assisted bioremediation, metal-resistant plant growth-promoting bacteria (PGPB) must facilitate plant growth by restricting excess metal uptake in plants, leading to prevent its bio-amplification in the ecosystem. The aims of our study were to isolate and characterize copper (Cu)-resistant PGPB from waste water receiving contaminated soil. In addition, we investigated the phytotoxic effect of copper on the lentil plants inoculated with copper-resistant bacteria Providencia vermicola, grown in copper-contaminated soil. Copper-resistant P. vermicola showed multiple plant growth promoting characteristics, when used as a seed inoculant. It protected the lentil plants from copper toxicity with a considerable increase in root and shoot length, plant dry weight and leaf area. A notable increase in different gas exchange characteristics such as A, E, C ᵢ , g ₛ , and A/E, as well as increase in N and P accumulation were also recorded in inoculated plants as compared to un-inoculated copper stressed plants. In addition, leaf chlorophyll content, root nodulation, number of pods, 1,000 seed weight were also higher in inoculated plants as compared with non-inoculated ones. Anti-oxidative defense mechanism improved significantly via elevated expression of reactive oxygen species -scavenging enzymes including ascorbate peroxidase, superoxide dismutase, catalase, and guaiacol peroxidase with alternate decrease in malondialdehyde and H₂O₂ contents, reduced electrolyte leakage, proline, and total phenolic contents suggesting that inoculation of P. vermicola triggered heavy metals stress-related defense pathways under copper stress. Overall, the results demonstrated that the P. vermicola seed inoculation confer heavy metal stress tolerance in lentil plant which can be used as a potent biotechnological tool to cope with the problems of copper pollution in crop plants for better yield.

The biosorption capability of two marine macroalgae (green Ulva lactuca and brown Fucus vesiculosus) was evaluated in the removal of toxic metals (Hg, Cd and Pb) from saline waters, under realistic conditions. Results showed that, independently of the contamination scenario tested, both macroalgae have a remarkable capacity to biosorb Hg and Pb. In single-contaminant systems, by using only c.a. 500 mg of non-pre-treated algae biomass (size <200 μm) per litter, it was possible to achieve removal efficiencies between 96 and 99 % for Hg and up to 86 % for Pb. Despite the higher removal of Hg, equilibrium was reached more quickly for Pb (after 8 h). In multi-contaminant systems, macroalgae exhibited a similar selectivity toward the target metals: Hg > Pb> > Cd, although Pb removal by U. lactuca was more inhibited than that achieved by F. vesiculosus. Under the experimental conditions used, none of the macroalgae was effective to remove Cd (maximum removal of 20 %). In all cases, the kinetics of biosorption was mathematically described with success. Globally, it became clear that the studied macroalgae may be part of simple, efficient, and cost-effective water treatment technologies. Nevertheless, Fucus vesiculosus has greater potential, since it always presented higher initial sorption rates and higher removal efficiencies.

This work presents a combination of geochemical, mineralogical, and biological data obtained in water reservoirs located in one of the most paradigmatic mining regions, suffering from acid mine drainage (AMD) problems: the Iberian Pyrite Belt (IPB). Four water reservoirs located in the Spanish sector of the IBP, storing water for different purposes, were selected to achieve an environmental classification based on the effects of AMD: two mining dams (Gossan and Águas Ácidas), a reservoir for industrial use (Sancho), and one with water used for human supply (Andévalo). The results indicated that the four reservoirs are subject to the effect of metallic loads from polluted rivers, although with different levels: Águas Ácidas > Gossan > Sancho ≥ Andévalo. In accordance, epipsammic diatom communities have differences in the respective composition and dominant taxa. The dominant diatoms in each reservoir indicated acid water: Pinnularia acidophila and Pinnularia aljustrelica were found in the most acidic dams (Gossan and Águas Ácidas, with pH <3), Pinnularia subcapitata in Sancho (pH 2.48–5.82), and Eunotia exigua in Andévalo (pH 2.34–6.15).

Air quality depends mainly on changes in emission of pollutants and their precursors. Understanding its characteristics is the key to predicting and controlling air quality. In this study, complex networks were built to analyze topological characteristics of air quality data by correlation coefficient method. Firstly, PM2.5 (particulate matter with aerodynamic diameter less than 2.5 μm) indexes of eight monitoring sites in Beijing were selected as samples from January 2013 to December 2014. Secondly, the C–C method was applied to determine the structure of phase space. Points in the reconstructed phase space were considered to be nodes of the network mapped. Then, edges were determined by nodes having the correlation greater than a critical threshold. Three properties of the constructed networks, degree distribution, clustering coefficient, and modularity, were used to determine the optimal value of the critical threshold. Finally, by analyzing and comparing topological properties, we pointed out that similarities and difference in the constructed complex networks revealed influence factors and their different roles on real air quality system.

Continual growth of energy-related CO₂ emissions in China has received great attention, both domestically and internationally. In this paper, we evaluated the CO₂ emissions in five major energy consumption sectors which were evaluated from 1991 to 2012. In order to analyze the driving factors of CO₂ emission change in different sectors, the Kaya identity was extended by adding several variables based on specific industrial characteristics and a decomposition analysis model was established according to the LMDI method. The results demonstrated that economic factor was the leading force explaining emission increase in each sector while energy intensity and sector contribution were major contributors to emission mitigation. Meanwhile, CO₂ emission intensity had no significant influence on CO₂ emission in the short term, and energy consumption structure had a small but growing negative impact on the increase of CO₂ emissions. In addition, the future CO₂ emissions of industry from 2013 to 2020 under three scenarios were estimated, and the reduction potential of CO₂ emissions in industry are 335 Mt in 2020 under lower-emission scenario while the CO₂ emission difference between higher-emission scenario and lower-emission scenario is nearly 725 Mt. This paper can offer complementary perspectives on determinants of energy-related CO₂ emission change in different sectors and help to formulate mitigation strategies for CO₂ emissions.

The water quality in Poyang Lake, the largest freshwater lake in China, has deteriorated steadily in recent years and local governments have made efforts to manage the potential eutrophication. In order to investigate the transport and retention processes of dissolved substances, the hydrodynamic model, Environmental Fluid Dynamics Code (EFDC) was applied by using the concept of water age. The simulated results showed agreement with the measured water level, discharge, and inundation area. The water age in Poyang Lake was significantly influenced by the variations of hydrological conditions. The annual analysis revealed that the largest averaged water age was observed during the wet year (2010) with 28.4 days at Hukou, the junction of the Yangtze River and Poyang Lake. In the normal season (April), the youngest age with 9.1 days was found. The spatial distribution of water quality derived from the remote sensing images suggested that a higher chlorophyll-a concentration, lower turbidity, and smaller water age in the eastern area of Poyang Lake might threaten the regional aquatic health. The particle tracking simulation reproduced the trajectories of the dissolved substances, indicating that the water mass with greater nutrient loading would further lead to potential environmental problems in the east lake. Moreover, the water transfer ability would be weakened due to dam (Poyang Project) construction resulting in the rising water levels in periods of regulation. Generally, this study quantified an indicative transport timescale, which could help to better understand the complex hydrodynamic processes and manage wetland ecosystems similar to Poyang Lake.

In this study, iron oxides obtained from used disposable heating pads are used as an anode material in lithium ion batteries. Fe₃O₄ and Fe₂O₃ phases are identified using XRD. Additionally, the existence of other substances, such as carbon and NaCl, are determined using EDS dot mapping. Purified powder (PP) is prepared by washing the obtained powder (OP) with distilled water and ethanol. Heat-treated powder (HP) is prepared by heating PP at 600 °C. The electrochemical result shows that PP delivers a discharge capacity of ∼700 mAh g⁻¹ after 50 cycles. HP delivers a higher initial capacity of 1170 mAh g⁻¹; however, the discharge capacity decreases drastically to 500 mAh g⁻¹. These results were similar to those determined for commercial iron oxide in previous studies.

Modern society increasingly requires achieving the goal of remediation and at the same time minimizing the waste to be disposed. Although the pump and treat is a consolidated technology option for the decontamination of groundwater polluted by heavy hydrocarbons, it generates an excessive amount of waste (typically, dangerous). With the intent of reducing such waste, our study is concerned with the verification of the oil belt skimmer technology for the decontamination of a heavy hydrocarbon-polluted groundwater. For this purpose, several tests at laboratory scale and full-scale experimentations with duration greater than 1 year were carried out. The obtained results showed the feasibility of the investigated technology for groundwater decontamination in the cases where the water mobility (of the aquifer) was low and in the presence of oil thicknesses greater than 2 cm. The heavy hydrocarbon recovery capacities were in the range of 33.3–85.5 l/h with the best performances in the cases of supernatant thickness ≥2 cm and pumping of the water table in such a way that the oil acquires a higher mobility in the aquifer. Moreover, the recovery capacity was found to be dependent on the rainfall pattern as well as on the groundwater fluctuation. Compared to the pump-and-treat system, the investigated technology allowed reducing by 98.7 % the amount of waste to be disposed suggesting the use in presence of high thickness of the oils. Finally, in a view of system optimization, treatment trains based on the combination of the oil belt skimmer technology and the pump-and-treat system should be carefully assessed.

In the present study, metal-facilitated free radical generation in particulate matter (PM) and its association with deoxyribonucleic acid (DNA) damage were studied. The examined data showed that the concentration of fine PM in Pune exhibited seasonal variations. Inductively coupled plasma-atomic emission spectrometry (ICP-AES) was used to examine the metal composition, which showed the presence of metals such as Cu, Zn, Mn, Fe, Co, Cr, Pb, Cd, and Ni. Fe metal was present in the highest concentrations in both the seasons, followed by Zn. The scanning electron microscopy-energy-dispersive spectrometer (SEM-EDS) results also demonstrated that the fine PM particles deposited in summer samples were less than those of winter samples, suggesting that the PM load in winter was higher as compared to that in summer. Elemental mapping of these particles substantiates deposition of metals as Fe, Zn, etc. on particles. The electron paramagnetic species (EPR) technique was utilized for free radical detection, and plasmid DNA assay was utilized to study the genotoxicity of ambient fine PM. Obtained g values show the presence of radicals in PM samples of Pune. PM contains the C-centered radical with a vicinal oxygen atom (g = 2.003). In addition to this, the g value for Fe was also observed. Therefore, we intend that the radicals related with fine PM comprise metal-mediated radicals and produce DNA damage. The plasmid DNA assay results indicated that the TM₅₀ values (toxic mass of PM causing 50 % of plasmid DNA damage) of PM exhibited seasonal variations with higher TM₅₀ values for summer and lower TM₅₀ values during winter.