Metallic contamination is a widespread phenomena, particularly in areas impacted by human activities, and has become a relevant environmental concern. However, the toxicity of metals on fish requires full characterization in terms of short- and long-term effects. Thus, the purpose of this study was to determine the acute and chronic oxidative stress response in liver and gills of Gambusia holbrooki exposed to copper and cadmium. To assess the effects of these two metals, we adopted a strategy of analyzing the pollution effects caused by salts of the two metallic elements, and we quantified the oxidative stress biomarkers catalase, glutathione reductase, glutathione-S-transferases, and lipid peroxidation after exposure (4 and 28 days) to ecologically relevant concentrations, thus simulating actual conditions of exposure in the wild. Our results showed that copper elicited strong effects in all tested biomarkers for both acute and chronic challenges. Cadmium caused a similar response and was shown to cause significant changes particularly in catalase and glutathione-S-transferases activities. These findings evidence that ecologically relevant concentrations of common anthropogenic contaminants are causative agents of serious imbalances (namely oxidative stress) that are likely to trigger life-threatening events.

Compared to soil pollution by heavy metals and organic pollutants, soil pollution by fluorides is usually ignored in China. Actually, fluorine-contaminated soil has an unfavorable influence on human, animals, plants, and surrounding environment. This study reports on electrokinetic remediation of fluorine-contaminated soil and the effects of this remediation technology on soil fertility. Experimental results showed that electrokinetic remediation using NaOH as the anolyte was a considerable choice to eliminate fluorine in contaminated soils. Under the experimental conditions, the removal efficiency of fluorine by the electrokinetic remediation method was 70.35 %. However, the electrokinetic remediation had a significant impact on the distribution and concentrations of soil native compounds. After the electrokinetic experiment, in the treated soil, the average value of available nitrogen was raised from 69.53 to 74.23 mg/kg, the average value of available phosphorus and potassium were reduced from 20.05 to 10.39 mg/kg and from 61.31 to 51.58 mg/kg, respectively. Meanwhile, the contents of soil available nitrogen and phosphorus in the anode regions were higher than those in the cathode regions, but the distribution of soil available potassium was just the opposite. In soil organic matter, there was no significant change. These experiment results suggested that some steps should be taken to offset the impacts, after electrokinetic treatment.

Nitrogen (N) loss from vegetable cropping systems has become a significant environmental issue in China. In this study, estimation of N balances in both open-air and greenhouse vegetable cropping systems in China was established. Results showed that the total N input in open-air and greenhouse vegetable cropping systems in 2010 was 5.44 and 2.60 Tg, respectively. Chemical fertilizer N input in the two cropping systems was 201 kg N ha⁻¹ per season (open-air) and 478 kg N ha⁻¹ per season (greenhouse). The N use efficiency (NUE) was 25.9 ± 13.3 and 19.7 ± 9.4 % for open-air and greenhouse vegetable cropping systems, respectively, significantly lower than that of maize, wheat, and rice. Approximately 30.6 % of total N input was accumulated in soils and 0.8 % was lost by ammonia volatilization in greenhouse vegetable system, while N accumulation and ammonia volatilization accounted for 19.1 and 11.1 %, respectively, of total N input in open-air vegetable systems.

Pesticide contamination in the rice fields has manifested into a serious global environmental concern. Application of pesticides in the rice fields has deleterious effects on non-target organisms including nitrogen-fixing cyanobacteria which help to maintain the rice field fertility. In the present research endeavor, the effect of lambda cyhalothrin (5 % EC), a synthetic pyrethroid insecticide, has been studied on the growth and pigments content of Calothrix sp. (GUEco 1001), an indigenous strain isolated from rice grown areas of Brahmaputra floodplain. To study the toxic effect of lambda cyhalothrin, the test organism was exposed to varying concentrations of the insecticide i.e., 20 ppm, 40 ppm, 80 ppm, and 160 ppm based upon the determination of LC₅₀ for a period of 20 days. The result obtained in the laboratory showed a progressive decrease in the growth and pigments content by the test organism with increasing concentrations of the lambda cyhalothrin against time dose-dependent manner. At high dose (160 ppm), the test organism showed significant decrease in dry weight biomass (54.5 %), chlorophyll-a (68 %), carotenoids (38 %), phycocyanin (80 %), and nitrogen contents (55 %) over the control. A little but insignificant stimulatory effect on growth and chlorophyll-a contents was recorded in 20 ppm treatment of the insecticide that, however, was reversed in case of carotenoids and phycocyanin contents.

The Patagonian coast is characterized by the existence of pristine ecosystems which may be particularly sensitive to oil contamination. In this study, a simulated oil spill at acute and chronic input levels was carried out to assess the effects of contamination on the macrobenthic community structure and the bioturbation activity of sediments sampled in Caleta Valdés creek. Superficial sediments were either noncontaminated or contaminated by Escalante crude oil and incubated in the laboratory for 30 days. Oil contamination induced adverse effects on macrobenthic community at both concentrations with, for the highest concentration, a marked decrease of approximately 40 and 55 % of density and specific richness, respectively. Besides the disappearance of sensitive species, some other species like Oligochaeta sp. 1, Paranebalia sp., and Ostracoda sp. 2 species have a higher resistance to oil contamination. Sediment reworking activity was also affected by oil addition. At the highest level of contamination, nearly no activity was observed due to the high mortality of macroorganisms. The results strongly suggest that an oil spill in this protected marine area with no previous history of contamination would have a deep impact on the non-adapted macrobenthic community.

A multi-residue method, based on gas chromatography coupled to tandem mass spectrometry (GC-MS/MS), has been developed for the determination of 70 organic micropollutants from various chemical classes (organochlorinated, organophosphorous, triazines, carbamate and urea, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, pharmaceuticals, phenols, etc.) in surface waters. A single-step SPE extraction using OASIS HLB cartridges was employed for the recovery of target micropollutants. The method has been validated according to monitoring performance criteria of the Water Framework Directive, taking into account the approved guidelines on quality assurance and quality control. The recoveries ranged from 60 to 110 %, the coefficient of variation from 0.84 to 27.4 %, and the uncertainty from 6 to 37 %. The LOD varied from 6.0 to 40 ng/L. The limits of quantification for the priority pollutants anthracene, alachlor, atrazine, benzo(a)pyrene, chlorfenvinphos, diuron, isoproturon, nonylphenol, simazine, and terbutryn fulfill the criterion of <30 % of the relevant environmental standards. The method was employed to investigate the water quality in the basin of a transboundary river, Strymonas, in NE Greece during three sampling campaigns conducted in the year 2013. Thirty-nine compounds were detected in the river water. Metolachlor, diuron, isoproturon, salicylic acid, chlorfenvinphos, 1,2-benzanthracene, pyrene, diflubenzuron, and carbaryl exhibited the highest detection frequencies.

In January 2013, several serious haze pollution events happened in North China. Cimel sunphotometer measurements at an urban site of Beijing (Chinese Academy of Meteorological Sciences—CAMS) from 1 to 30 January 2013 were used to investigate the detailed variation of aerosol optical properties. It was found that Angstrom exponents were mostly larger than 0.80 when aerosol optical depth values are higher than 0.60 at the urban region of Beijing during January 2013. The aerosol optical depth (AOD) at the urban region of Beijing can remain steady at approximately 0.40 before haze happening and then increased sharply to more than 1.50 at 500 nm with the onset of haze, which suggests that the fine-mode AOD is a factor of 20 of the coarse-mode AOD during a serious haze pollution event. The single scattering albedo was approximately 0.90 ± 0.03 at 440, 675, 870 and 1,020 nm during the haze pollution period. The single scattering albedo at 440 nm as a function of the fine-mode fraction was relatively consistent, but it was highly variable at 675, 870 and 1,020 nm. Except on January 12 and 18, all the fine-mode particle volumes were larger than those of coarse particles, which suggests that fine particles from anthropogenic activities made up most of the haze. Aerosol type classification analysis showed that the dominant aerosol types can be classified as both “mixed” and “urban/industrial (U/I) and biomass burning (BB)” categories during the heavy haze period of Beijing in January of 2013. The mixed category occurrence was about 31 %, while the U/I and BB was about 69 %.

In the spring 2012, post-flotation tailings of the inactive impoundment Lintich (Slovakia) were sampled. In the impoundment sediment and also in its surrounding, we detected concentration of Pb, Zn, Cd, Cu, and Ba exceeding limiting values. We detected low values of the microbial biomass carbon and microbial activity in the impoundment sediment (LiS) and its dam (DAM) along with potential respiration stayed relatively low and therefore also substrate availability index and metabolic quotient (qCO₂) were higher in the control sample (REF) than in the LiS and the DAM. The low qCO₂ level indicates that microbial community, despite of dangerously high levels of heavy metals in sediment, is still able to sufficiently utilize sources of available organic carbon. Anyway, we could doubt function of the metabolic index as universal indicator of environment conditions, regarding the anthropogenic substrates. We confirmed changes in composition of the mite communities along gradient dam—impoundment. The percentage of eudominant, recendent, and subrecendent species increased at the expense of dominants and subdominants, all together with decreasing diversity and equitability of the community. We identified species Chamobates borealis, Carabodes rugosior, Metabelba propexa, and Pergalumna nervosa with negative respond under the heavy metal stress. Species Adoristes ovatus was indifferent and Dissorhina sp., Hafenrefferia gilvipes, and Oppiella nova prospered under the loaded conditions. Forty years after experimental afforestation, we expect specific community of actively surviving microorganisms and Oribatida species detected in the DAM are usual in the greatly degraded habitats or on sites in the early succession.

Although sulfonamides (SAs) are among the most commonly used veterinary drugs and their presence in the environment is well documented, knowledge of their fate and behavior in the soil environment is still limited, especially for sulfisoxazole (SSX) which is characterized by the lowest (among other SAs) pK ₐ value associated with acid-base equilibrium of sulfonamide group. Thus, this work was focused on determining the sorption potential of SSX onto natural soils differing in physicochemical properties. All the results were modeled using linear, Freundlich, Langmuir, Dubinin–Radushkevich, and Temkin sorption isotherms. The established sorption coefficients (K d) for SSX were quite low (from 0.27 to 0.95 L kg⁻¹), which indicated that this substance is highly mobile and has the potential to run off into surface waters and/or infiltrate ground water. The sorption data of SSX is well fitted to the Freundlich isotherm model (R ² > 0.968). Moreover, we assessed the sorption mechanism of these compounds in the edaphic environment with respect to organic matter (OM) content, pH, and ionic strength. To clarify the current state of knowledge, these factors were examined much more thoroughly than in previous investigations concerning other SAs. The wide range of ionic strength examined showed positive correlation of this factor and sorption of SAs. The results also yielded new insight into dependency of sorption of SAs on organic matter content in soil.

This study focuses on the feasibility of treating aged polycyclic aromatic hydrocarbons (PAHs)-contaminated soils using ethyl lactate (EL)-based Fenton treatment via a combination of parametric and kinetic studies. An optimised operating condition was observed at 66.7 M H₂O₂ with H₂O₂/Fe²⁺ of 40:1 for low soil organic carbon (SOC) content and mildly acidic soil (pH 6.2), and 10:1 for high SOC and very acidic soil (pH 4.4) with no soil pH adjustment. The desorption kinetic was only mildly shifted from single equilibrium to dual equilibrium of the first-order kinetic model upon ageing. Pretreatment with EL f c = 0.60 greatly reduced the mass transfer coefficient especially for the slow desorbed fraction (k ₛₗₒw) of high molecular weight (HMW) PAHs, largely contributed by the concentration gradient created by EL-enhanced solubility. As the major desorption obstacle was almost fully overcome by the pretreatment, the pseudo-first-order kinetic reaction rate constant of PAHs degradation of aged soils was statistically discernible from that of freshly contaminated soils but slightly reduced in high SOC and high acidity soil. Stabilisation of H₂O₂ by EL addition in combination with reduced Fe²⁺ catalyst were able to slow the decomposition rate of H₂O₂ even at higher soil pH.