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The increasing shortage of conventional water for crop irrigation in arid and semiarid regions is encouraging the use of nonconventional water resources. Nevertheless, concern about the presence and possible negative effects of emerging contaminants in reclaimed water can cause individuals to avoid using these water sources. To clarify the guarantees that reclaimed water offers, a mesocosm study was carried out. Lettuce plants were cultivated in pots watered with three different types of water (distilled, reclaimed, and spiked with contaminants of emerging concern). The results showed low concentrations of contaminants in the leachates and plant tissues when the reclaimed water was used. However, their concentrations were high when the pots were watered with the spiked water; this was mainly true for carbamazepine, which reached a maximum of 2982 ng L−1 in the leachates and 45.2 ng g−1 in the plant roots. In the lettuce watered with the spiked water, carbamazepine was found in the edible part at very low concentrations that did not imply any human risk. Finally, an acute toxicity test was performed on the leachates, which were found to be only slightly toxic in the spiked water. This work indicates that with the current technical improvements in active sludge water treatment, reclaimed water can be used for irrigation without the risk of contamination by contaminants of emerging concern. [ABSTRACT FROM AUTHOR]

In the field of agriculture, nanopesticides have been developed as an alternative to the conventional pesticides, being more efficient for pest control. However, before their widespread application it is essential to evaluate their safe application and no environmental impacts. In this paper, we evaluated the toxicological effects of two kinds of atrazine nanoformulations (ATZ NPs) in different biological models (Raphidocelis subcapitata , Danio rerio , Lemna minor , Artemia salina , Lactuca sativa and Daphnia magna) and compared the results with nanoparticle stability over time and the presence of natural organic matter (NOM). The systems showed different characteristics for Zein (ATZ NPZ) (184 ± 2 nm with a PDI of 0.28 ± 0.04 and zeta potential of (30.4 ± 0.05 mV) and poly(epsilon-caprolactone (ATZ PCL) (192 ± 3 nm, polydispersity (PDI) of 0.28 ± 0.28 and zeta potential of −18.8 ± 1.2 mV) nanoparticles. The results showed that there is a correlation between nanoparticles stability and the presence of NOM in the medium and Environmental Concentrations (EC) values. The stability loss or an increase in nanoparticle size result in low toxicity for R. subcapitata and L. minor. For D. magna and D. rerio, the presence of NOM in the medium reduces the ecotoxic effects for ATZ NPZ nanoparticles, but not for ATZ NPs, showing that the nanoparticles characteristics and their interaction with NOM can modulate toxic effects. Nanoparticle stability throughout the evaluation must be considered and become an integral part of toxicity protocol guidelines for nanopesticides, to ensure test quality and authentic results regarding nanopesticide effects in target and non-target organisms. [Display omitted] • Nanoparticle stability plays a crucial role in ecotoxicity studies. • Nanoparticle stabilities were evaluated in the presence and absence of NOM. • Nanoparticle size variation or precipitation reduces bioavailability. • NOM did not promote a significant difference in hazard concentrations. [ABSTRACT FROM AUTHOR]

La evaluación de riesgos ambientales por productos fitosanitarios es un componente de importancia en los estudios de impacto ambiental en el sector agrícola. Se evaluó la ecotoxicidad de los plaguicidas de suelo, lindano y clorpirifos, sobre la mortalidad del oligoqueto Limnodrilus hoffmeisteri (CL50 24h) y tres plantas, en las cuales se observaron los siguientes efectos subletales: germinación en Lactuca sativa (CI90 96h), crecimiento de raíz en Lycopersicon esculentum (CI50 96h) y clorosis, necrosis, ruptura y formación de hojas nuevas en la lenteja de agua, Lemna minor (CE50 48h). En ambos agroquímicos se observó en general el siguiente orden de ecotoxicidad decreciente: Lycopersicon Lemna Lactuca Limnodrilus. En los tres ensayos con plantas se observó una mayor toxicidad del organofosforado clorpirifos. Se analizan las perspectivas de empleo, en el Perú, de estas herramientas ecotoxicológicas para la evaluación de riesgos ambientales por productos fitosanitariosThe environmental risk assessments of phytosanitary products is a main subject in the studies of the impact assessment in the agriculture areas. The ecotoxicity of the soil pesticides lindane and chlorpyrifos was performed with: the mortality in tubifids worm Limnodrilus hoffmeisteri (LC50 24h) and in three plants: seed germination assay in Lactuca sativa (IC90 96h), root elongation assay in Lycopersicon esculentum (IC50 96h) and the duckweed test in Lemna minor (EC50 48h) (chlorosis, necrosis, colony breakup and new fronds increased) sublethal effects were analized. Both agrochemistries in general showed a decrease order of ecotoxicity: Lycopersicon Lemna Lactuca Limnodrilus. In the three plant bioassays were seen a high toxicity to the organophosphate chlorpyrifos. The perspectives of use of these phytosanitary products in Perú, was analized for environmental risk assessment.

Abstract: Since the 1990s red-tide blooms of Fibrocapsa japonica have frequently been observed in European waters; despite their recurrence also in the Adriatic coastal areas, they have never been conclusively linked to ichthyotoxic events. Since the toxicity of F. japonica is still under debate and its effects differ among the strains, in this study all the compounds previously postulated as involved in the toxic mechanism, such as brevetoxins, fatty acids and ROS, were screened for Adriatic strains. Whole algal extracts were analyzed for brevetoxin PbTx-2, which was not found, and for a qualitative and quantitative analysis of fatty acids. The fatty acid profile evidenced the presence of PUFAs, with considerable amounts of 18:4n-3, 20:4n-6, and 20:5n-3, as already found in different strains, but with a lower amount of arachidonic acid (20:4n-6). None of the PUFAs was released in the extracellular medium. Different toxicological assays (Vibrio fischeri, Artemia sp., haemolysis of fish erythrocytes) were performed using algal cellular, extracellular or subcellular samples as well as fractions of the algal extract, in order to identify the toxic compounds. The tested cultures were found to inhibit V. fischeri bioluminescence, to affect Artemia nauplii viability and to have haemolytic effects comparable to those previously observed in different strains. The solid phase extraction (SPE) of the Adriatic F. japonica extracts resulted in a high concentration of PUFAs in two main fractions, which caused mortality in Artemia nauplii and inhibition of V. fischeri bioluminescence. Fish (Dicentrarchus labrax) assays were also performed, reporting mortality after long exposure times and the cause of fish death was investigated. A significant increase of H2O2 in the tanks where sea basses were exposed to F. japonica was obtained, indicating that the presence of fish stimulates H2O2 production by algal cells and leading to the hypothesis of H2O2 involvement in F. japonica toxicity. The presence of oxidative stress in the exposed fish was confirmed by the increased malondialdehyde concentration in their gills. Overall these results indicate that since F. japonica cells can easily cling to fish gills, due to their high polysaccharide production, it is presumable that high PUFA amounts are released in loco, as a result of cell breakage, and that exert their toxicity together with ROS. This study shows that the Adriatic strains of F. japonica can be harmful to higher level organisms. Nevertheless a high cell density and a long lasting bloom are necessary to cause severe damage to fish gills or death for crustaceans. [Copyright &y& Elsevier]

Abstract: The aim of this study was to compare the effect of two different dilution soils on the toxicity of an arsenic-contaminated mine soil by the collembolan reproduction assay. We diluted the contaminated soil either with an ISO soil or with a non-polluted soil having pedological and geological characteristics as similar as possible to those of the polluted site. The results were very different according to the dilution soil used: the lowest observed effect concentration (LOEC) was 1/256 with the ISO soil versus 1/4 with the natural dilution soil. The dilution soils influenced the bioavailability of xenobiotics and our results could be explained by the observed differences in arsenic and total organic carbon (TOC) concentrations in the pore water. Our results indicate that the physico-chemical characteristics of the dilution soil and their possible interactions with the polluted soil and its contaminants have to be taken into account in the interpretation of bioassays on polluted soils. [Copyright &y& Elsevier]

• Photocatalytic activity of Mg-doped ZnO was enhanced upon increased Mg2+ content. • Photodegradative process disinfected and improved the BOD 5 /COD ratio of wastewater. • Phytotoxicity tests showed that treated wastewater can be used in agriculture. • Mg-doped ZnO did not inhibit the proliferation of fibroblast cells. Structural, morphological, optical, and photocatalytic properties of Mg-doped ZnO nano-semiconductors were investigated. All nanostructures exhibited spherical morphology with average crystallite diameters and band gap energy values between 47–54 nm and 3.00–3.05 eV, respectively. The increase in Mg ion contents (0.1–1.0 mol%) enhanced the photocatalytic activity of the nano-semiconductors for decontamination of non-treated laundry wastewater, degrading approximately 53% of pollutants (with absorption at λ = 290 nm) after 240 min of UV–vis irradiation. The best photocatalytic efficiency exhibited by ZnO-Mg 1.0% is probably associated to an increase in the amount of oxygen vacancies (V O) and consequent reduction in the recombination rate of electron-hole (e–h) pairs. The treatment of laundry wastewater also demonstrated reduction of 31% in total organic carbon (TOC), improvement in the biodegradability of the contaminants, and a high efficacy in wastewater disinfection. In addition, the treated laundry wastewater promoted a germination rate of cucumber seeds equivalent to the observed rate for the control. Phytotoxicity of treated wastewater on tomato roots reduced about 73%, indicating that the treated laundry wastewater does not essentially need to be disposed into water bodies. Instead, it may be reused as irrigation water. Interestingly, Mg-doped ZnO nano-semiconductors did not cause damage to normal and healthy fibroblast cells, demonstrating their potential to be used in environmental remediation, considering the low-cost, non-toxicity, and high efficiency of these nanomaterials. [ABSTRACT FROM AUTHOR]

Germination inhibition of zoospores of the aquatic, brown algal macrophyte Ecklonia radiata was employed to assess the toxicity of sewageeffluents under short to long term exposure and under modified salinity conditions. The rate of germination inhibition was determined forexposure times between 2 and 48 h in salinity modified and unmodified regimes and under reduced salinity conditions alone. The results indicated that rate of germination inhibition increased with duration of exposure to sewage effluents and to salinity reduction alone, and that response to the effluents may be enhanced under conditions of reduced salinity. Whilst the effect of primary treated effluent was primarily that of toxicity, secondary treated effluent effects appeared to be primarily that of reduced salinity although at a greater rate than would be expected for salinity reduction alone. The assay is suggested to provide a mechanism for monitoring sewage effluent quality and to monitor potential impacts of sewage effluent discharge on kelp communities in southern Australia. [ABSTRACT FROM AUTHOR]