Currently, there are increasing efforts to utilize nanoremediation as an environmental technology for cleaning up polluted environments using nanoscale zero-valent iron (nZVI); however, concerns exist regarding the long-term environmental impact of this strategy. In this study, an innovative methodology for evaluating nZVI impact on soil bacteria is utilized, based on transcriptional analysis of three novel biomakers: tnaA, sodB and trx genes. At the same time, classical toxicological bioassays with the nematode Caenorhabditis elegans were performed. Microcosms treated with 1, 5 and 10 % w/w of nZVI were set up using a commercial standard soil and incubated for 21 days. The tnaA gene, involved in indole production, was significantly upregulated at all assessed nZVI concentrations, suggesting that bacterial cells used this molecule to inform the rest of the community about the changes produced upon nZVI soil treatment. The higher the exposure time, the lower nZVI concentration needed to detect these changes. Consequently, soil bacteria activate a cellular adaptive response to cope with the nZVI-induced oxidative stress, increasing the expression of genes encoding key reactive oxygen species (ROS)-scavenging enzymes; in fact, an upregulation of the sodB and katB genes was recorded upon nZVI exposure. On the contrary, C. elegans survival and growth endpoints were not affected at any nZVI concentration whereas the exposure time significantly increased nematode growth in the soil. Therefore, despite the lack of toxicity revealed by the classical conducted tests, the transcriptional analyses demonstrated the usefulness of combining the set of proposed biomarkers for early detection and monitoring the impact of nZVI on soil bacteria after environmentally important periods of exposure.

Wastewater (WW) for irrigation and application of biosolids in soil is becoming important as it is going to become very common in the near future. By 2050, the world is going to have four billion people living in water-scarce countries, making it a norm of freshwater for the cities and WW for agriculture. Further, biosolids might still be used as green biofertilizers for soils, if they are improved from an ecological point of view. However, application of biosolids in soil is argued because of the amount of organic pollutants that compromise the dynamic equilibrium of the biological systems. Therefore, information on the concentration, behavior, and cycling of organic pollutants as well as their possible degradation pathways is needed to predict, prevent, and remediate these pollutants from different sources including WW and biosolids. Among the group of organic pollutants, emerging contaminants (ECs) enter into the soil with the irrigation water from treated effluents and fertilization by biosolids. Quantification of ECs from WW and biosolids is of main importance to predict the toxic effects of WW effluents and sludge. Moreover, their incorporation into vegetables through irrigation and their magnification through natural food webs have been proved and must be monitored. This review presents information on the different sources of emerging contaminants and linking with the ecological effects they produced by reacting in the environment during various applications of WW and biosolids in soil. The available methods for analysis and quantification of ECs in different matrices, such as WW and biosolids, are also presented.

A macroporous glycidyl methacrylate (GMA)–methylmethacrylate (MMA)–divinyl benzene (DVB) terpolymer functionalized with diethylenetriamine tetraacetic acid (DTTA) (GMA-MMA-DVB-DTTA) sorbent was successfully applied for the uptake of Cu(II) from the aqueous solutions. Adsorption characteristics for copper ion were investigated by a batch sorption in under different experimental conditions, and the optimum parameters for the quantitative sorption of Cu(II) ion were found to be as follows: pH of 7.0, a contact time of 30.0 min, and a sorbent amount/solution volume ratio of 1.5 mg/mL. The quantitative elution from the sorbent was performed with 1.0 M HCl (>95 %). Among three kinetic models, the pseudo-second-order kinetic model provides the best correlation for the process. The nonlinear resolution of the Langmuir isotherm equation has been found to show the closest fit to the equilibrium data. The results indicates that the presence of the competitor ions (Al, Ba, Co, Mn, Mg, and Ni) has no obvious influence on the sorption of Cu(II) ion under the optimum conditions and the polymeric sorbent has a good selectivity for the sorption of Cu(II) ions with a sorption percent of ≥99 %. Sorption/desorption studies were performed for ultrapure, tap, bottled drinking and industrial wastewater samples, and it is examined that the proposed method has been successfully applied to the real samples for the removal of Cu(II) acceptable accuracy and precision. The results of this work indicated that the polymeric sorbent could be a simple and suitable method for the effective removal of Cu(II) ions from waters.

An experimental study was performed to determine the feasibility of using physically treated Candida tropicalis cells for sorption of Cu(II) and phenol, the role of competition between phenol molecules and Cu(II). The yeast cells were lyophilized (LC), heat-treated at 65 °C for 24 h (HT1), at 90 °C for 24 h (HT2), and 72 h (HT3), inactivated at 120 °C and 104 kPa for 20 min (PC). The adsorption isotherms were determined in batch system. Experimental equilibrium data were evaluated using Langmuir, Freundlich, and Dubinin–Radushkevich isotherm models by linear and non-linear regression. The adsorbed Cu(II) and phenol amounts by yeast cells were decreased due to the physical treatments of cells. With the increase of biomass dosage from 1 to 10 g L⁻¹, the adsorption efficiency was increased. The Cu(II) adsorption capacity was also determined in the presence of phenol at various initial concentrations, and in these systems, phenol adsorption isotherms were determined. In the presence of phenol, the Cu(II) sorption capacity by lyophilized cells and carbon particles was decreased. The most commonly used sorbent in water treatment is activated carbon with large specific surface; therefore, the results were compared with the experimental data obtained by using activated carbon (AC).

Spatio-temporal cancer mortality studies in Spain have revealed patterns for some tumours which display a distribution that is similar across the sexes and persists over time. Such characteristics would be common to tumours that shared risk factors, including the chemical soil composition. The objective of the present study is to assess the association between levels of chromium and arsenic in soil and the cancer mortality. This is an ecological cancer mortality study at municipal level, covering 861,440 cancer deaths in 7917 Spanish mainland towns from 1999 to 2008. Chromium and arsenic topsoil levels (partial extraction) were determined by ICP-MS at 13,317 sampling points. To estimate the effect of these concentrations on mortality, we fitted Besag, York and Mollié models, which included, as explanatory variables, each town’s chromium and arsenic soil levels, estimated by kriging. In addition, we also fitted geostatistical-spatial models including sample locations and town centroids (non-aligned data), using the integrated nested Laplace approximation (INLA) and stochastic partial differential equations (SPDE). All results were adjusted for socio-demographic variables and proximity to industrial emissions. The results showed a statistical association in men and women alike, between arsenic soil levels and mortality due to cancers of the stomach, pancreas, lung and brain and non-Hodgkin’s lymphomas (NHL). Among men, an association was observed with cancers of the prostate, buccal cavity and pharynx, oesophagus, colorectal and kidney. Chromium topsoil levels were associated with mortality among women alone, in cancers of the upper gastrointestinal tract, breast and NHL. Our results suggest that chronic exposure arising from low levels of arsenic and chromium in topsoil could be a potential risk factor for developing cancer.

The Spent Pot Liner (SPL) is a toxic solid waste from the aluminum industry. The genotoxic potential of SPL and its main chemical components (fluoride, cyanide, and aluminum) were evaluated on vegetal (Allium cepa L. system test) and human cells (comet assay) in the present study. Meristematic cells from A. cepa submitted to the treatments presented a reduction in the mitotic index (MI) and an increase in the frequency of chromosome alterations (CA). The SPL treatment reduced MI in 50 % when compared to the negative control. In addition, there were significant reductions in MI on the cyanide and aluminum treatments. All frequencies of chromosome alterations observed to the treatments were statistically different from control, and cyanide was the most cytogenotoxic component. The exposed cells to the treatments also increased the frequency of condensed nuclei. The comet assay on human leukocytes demonstrated that all treatments induced DNA fragmentation. Fluoride and SPL showed similar damages to the positive control (doxorubicin, UA = 259.7) and higher than the negative control (CaCl₂ 0.01 M, UA = 16.5). The aluminum induced intermediary damage, and the cyanide was responsible for minor damage. In conclusion, both SPL and its main components presented genotoxic and mutagenic potential on evaluated cells. Fluoride was the main genotoxic component for human leukocytes while cyanide leads the higher alterations for A. cepa meristematic cells. Thus, the storage and discard of this residue should be regulated and supervised more closely in order to reduce the risk of environmental pollution and its contact with human.

Over the last few decades, the concentration of cadmium (Cd) in the environment has increased considerably in many countries due to anthropogenic activities. Cd is one of the most toxic pollutants in the environment and affects many metabolic processes in plants. The main objective of this study was to evaluate the response of the production, nutritional, and enzymatic antioxidant system of two tomato genotypes (Calabash Rouge and CNPH 0082) grown in tropical soils that were treated with doses of Cd. Soil samples were collected from the layer of earth at a depth of 0–0.2 m in areas subjected to a minimum of human disturbance. The concentrations of Cd applied to the soil samples were 0, 1, 2, and 4 times (0, 3, 6, and 12 mg kg⁻¹ of Cd) the agricultural intervention value adopted by current environmental legislation in the state of São Paulo, Brazil. Analysis of superoxide dismutase, catalase, glutathione reductase, guaiacol peroxidase, and ascorbate peroxidase activities, formation of stress indicator compound (malondialdehyde—MDA and hydrogen peroxide), parameters of production—dry mass of the shoot and root system (here in after “shoots” and “roots”), as well as nutrition, and both the bioavailable and total levels of this metal in the soil were performed. When the bioavailable content and total levels of Cd in the soil increased as a result of this metal doses applied, the biomass of both shoots and roots decreased in both genotypes (with the exception of the CNPH 0082 grown in clay soil) and displayed lower SPAD (relative chlorophyll index) values when exposed to contaminated environments with Cd concentrations. Cadmium treatment resulted in nutritional imbalances, mainly in terms of N, P, and Mn metabolism. Plants subjected to an elevated available content of metal in the soil exhibited increases in content of MDA and hydrogen peroxide and increased activity of catalase, ascorbate peroxidase, and guaiacol peroxidase in plant tissues when grown in both clay soil and sandy soil. Cadmium was phytotoxic to the plants causing a nutritional imbalance, especially on the metabolisms of N, P, and Mn. An oxidative stress condition was established in response to the Cd treatments applied, which led to changes in peroxidase activity.

Selective adsorption of Pb(II) and Cr(VI) by surfactant-modified and unmodified zeolites is discussed in this paper. The influences of pH, ionic strength, temperature, and adsorption time on Cr(VI) and Pb(II) adsorption are studied, The characteristics of the surface and inner structures of zeolites before and after modification are analyzed through infrared spectroscopy, scanning electron microscopy, X-ray diffraction, Brunauer–Emmett–Teller analysis, and zeta potential measurement. Results show that the characteristics of electric charge on the zeolite surface had changed after modification, which resulted in selective adsorption of Cr(VI) and Pb(II). Moreover, kinetic study reveals that adsorption by the different zeolites coincides with the Langmuir model and pseudo-second-order kinetic equation. The intraparticle diffusion equation proves that the Cr(VI) adsorption is mainly electrostatic, whereas Pb(II) adsorption proceeds via intrapore and electrostatic adsorption on the zeolite surface. This difference in mechanisms endows selectivity of metal ion adsorption by the modified zeolites. This study provides a reference on zeolite modification for use in various applications, such as wastewater treatment.

The growing production of beef has resulted in the increased volume of liquid residues generated during slaughtering and processing, known as slaughterhouse wastewater. In an attempt to reduce the organic content of this wastewater, blood has been separated from the water, generating slaughterhouse wastewater from green line slaughter and processing (SHWW in natura). The objective of this study was to determine the physical, chemical, and toxicological characteristics of SHWW in natura collected from a bovine slaughterhouse and locker. The results obtained from this characterization showed a high concentration of solids, total volatile acids, alkalinity, macro and micro nutrients, and organic matter (BOD₅ ²⁰°C, COD, and DOC). The effluent presented acute toxicity to the test-organisms P. putida, E. coli, and D. similis, and chronic toxicity to the test-organisms C. silvestri, C. dúbia, E. coli, P putida, and P. subcaptata. Based on the ecotoxicological tests, it was concluded that the compounds of the SHWW in natura were more toxic to microcrustaceans and algae than to bacteria.

This study presents a complementary approach for the evaluation of water quality in a river basin by employing active and passive sampling. Thirty-eight hydrophilic organic compounds (HpOCs) (organohalogen herbicides, organophosphorous pesticides, carbamate, triazine, urea, pharmaceuticals, phenols, and industrial chemicals) were studied in grab water samples and in passive samplers POCIS collected along Strymonas River, Northern Greece, at three sampling campaigns during the year 2013. Almost all the target compounds were detected at the periods of high rainfall intensity and/or low flow rate. The most frequently detected compounds were aminocarb, carbaryl, chlorfenviphos, chloropropham, 2,4-D, diflubenzuron, diuron, isoproturon, metolachlor, and salicylic acid. Bisphenol A and nonylphenol were also occasionally detected. The use of POCIS allowed the detection of more micropollutants than active sampling. Low discrepancy between the concentrations obtained from both samplings was observed, at least for compounds with >50 % detection frequency; thus, POCIS could be a valuable tool for the selection and monitoring of the most relevant HpOCs in the river basin. Results showed relatively low risk from the presence of HpOCs; however, the potential risk associated with micropollutants such as carbaryl, dinoseb, diuron, fenthion, isoproturon, metolachlor, nonylphenol, and salicylic acid should not be neglected.