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Poultry litter is widely applied as a fertilizer even though it is one of the main antibiotic sources to agricultural soils. Long-term sublethal effects (56 days) on the antioxidant system of Eisenia andrei earthworms following exposure to fluoroquinolone-contaminated poultry litter (enrofloxacin + ciprofloxacin) at 5.0, 10, and 20 g kg-1 were evaluated. The following biomarkers were assessed: superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), reduced glutathione (GSH), and a lipid peroxidation (LPO) proxy. Significant CAT and SOD increases, and a moderate positive correlation (ρ = 0.67, p < 0.05) between these enzymes was observed. Glutathione-S-transferase levels increased significantly at 10 g kg-1, while GSH exhibited a dose-dependent response at 5.0 mg kg-1 (4-106%), 10 mg kg-1 (28-330 %), and 20 mg kg-1 (45-472%). LPO levels exhibited a decreasing trend with increasing poultry litter concentrations of 8-170% (5.0 g kg-1), 7-104% (10 mg kg-1), and 3-6% (20 mg kg-1). A principal component analysis (PCA) highlighted increased SOD and CAT activities, possibly due to increased reactive oxygen species (ROS) concentrations. Biological health status assessments based on the biomarker response index indicate major alterations in the first month of exposure and becoming moderate in the second month. These findings indicate an antioxidant system attenuation trend. It is possible, however, that successive poultry litter applications may reduce the long-term recovery capacity of the evaluated biomarkers.

Data concerning the toxicity of the transformation products of some pesticides considered emerging contaminants are still incipient. This study aimed to evaluate acute (filter paper contact and avoidance test) and chronic (assays carried out in Red yellow Ultisoil) effects of the transformation products of the fungicide imazalil (IMZ) by heterogeneous photocatalysis (TiO2/UV) in Eisenia andrei. Some endpoints, i.e. biomass variation, disorder in reproduction and avoidance behavior, cytotoxicity (cell density and feasibility), and coelomic fluid (eleocytes and amoebocytes, immune cell) and antioxidant system (catalase (CAT) and glutathione S-transferase (GST)) changes were assessed. The studied degradation times (6, 18, 35 and 90 min) represented 70; 35; 10 and 0% of the initial IMZ concentration (5 mg L−1). No lethality and no significant difference in biomass variations were noted in the acute contact test. Decreased GST and increased CAT activities, as well as cell typing alterations and decreased cell viability and density detected at the 90-min degradation timepoint (PDT-90) indicate direct cytotoxic IMZ transformation product effects. In the avoidance test, no significant earthworm repulsion or attraction was observed. PDT-90 transformation products were responsible for losses in biomass and a reduction in the number of earthworm cocoons and juveniles present in soil. No cytotoxic effects were observed in the long term, although increased CAT and decreased GST activities were observed. Investigations on the relative toxicity of IMZ transformation products are relevant for future discussions regarding the environmental treatment, control and destination of this compound and its derivatives.

The final disposal of municipal solid waste (MSW) in dumpsites is still a reality worldwide, especially in low- and middle-income countries, leading to leachate-contaminated zones. Therefore, the aim of this study was to carry out soil and leachate physicochemical, microbiological, and toxicological characterizations from a non-operational dumpsite. The L-01 pond samples presented the highest physicochemical parameters, especially chloride (Cl; 4101 ± 44.8 mg L

Contaminants of emerging concern (CECs) are released daily into surface water, and their recalcitrant properties often require tertiary treatment. Electrochemical oxidation (EO) is often used as an alternative way to eliminate these compounds from water, although the literature barely addresses the neurotoxic effects of residual by-products. Therefore, this study investigated the performance of EO in the removal of five CECs (alprazolam, clonazepam, diazepam, lorazepam, and carbamazepine) and performed neurotoxicity evaluations of residual EO by-products in Wistar rat brain hippocampal slices. Platinum-coated titanium (Ti/Pt) and boron-doped diamond (BDD) electrodes were studied as anodes. Different current densities (13-75 A m-2), pH values (3-10), electrolyte dosages (NaCl), and matrix effects were assessed using municipal wastewater (MWW). The drugs were successfully degraded after 5 min of reaction for both the Ti/Pt and BDD electrodes when a current density of 75 A m-2 was applied. For Ti/Pt and BDD, neutral and acidic pH demonstrated better CEC removal performance, respectively. Compound degradation using MWW achieved 40% removal after 120 min for Ti/Pt and ranged between 33 and 52% for the BDD anode. For Ti/Pt, neurotoxicity studies using MWW indicated a decrease in reactive oxygen species (ROS) signals. However, when an artificial cerebrospinal fluid (ACSF) medium was reapplied, the signal recovered and increased to a value above the baseline, indicating that cells recovered part of their normal activity but remained in a different condition. For the BDD anode, the treated MWW did not cause significant ROS production variations, suggesting that he EO was effective in eliminating the toxicity of the treated solution.

This study is aimed at investigating the influence of different scavenger species of radicals that might possibly be involved in the TiO2/UVA photocatalytic degradation of Indigo Carmine dye. The effect caused by the presence of hydroxyl radicals (1-butanol and 2-propanol), positive holes (h+) (potassium iodide) and singlet oxygen (azide) was studied. Kinetics and optimal degradation conditions were evaluated using a factorial experiment design. The highest pseudo-first-order kinetics (k = 5.22 × 10−2 ± 0.002 and t1/2 = 13.25 ± 0.49 min) was achieved at pH 4.0, 6 mg L−1 of Indigo Carmine dye and 12 mg L−1 of TiO2. Mineralization was not achieved, and direct photolysis was not observed under the studied conditions. Indigo Carmine degradation occurs mainly due to oxidation in the positive hole (h+) followed by singlet oxygen action and on a smaller scale by hydroxyl radical. The use of the aforementioned radical scavengers made it possible to verify the mechanism and kinetics of Indigo Carmine dye through TiO2 heterogeneous photocatalysis.

Leachate from solid waste landfill is a dark liquid of variable composition and possible source of contamination of groundwater and surface waters. This study aims to assess skimmed milk flocculation and ultracentrifugation as viral concentration methods associated to different nucleic acid extraction protocols in order to establish a methodology for virus recovery from sanitary landfill leachate. Spiking experiments using human adenovirus (HAdV) and bacteriophage PP7 revealed the association of QIAamp Fast DNA Stool mini kit® nucleic acid extraction and ultracentrifugation as an effective method for recovering HAdV (346.18%) and PP7 (523.97%) when compared to organic flocculation method (162.64% for HAdV and 0.61% for PP7) that presented PCR inhibition in all undiluted samples. Ultracentrifugation applied in three landfill samples confirm efficiency of the methodology detecting HAdV in all samples with a mean of 3.44E + 06 ± 1.56E + 06 genomic copies/mL. Nucleotide sequencing characterized HAdV as belonging to group B and F. JC polyomavirus (JCPyV) was also investigated in those samples; however, detection was not observed. Methodologies for detection of viruses in leachate can be useful to generate data for future health risk analysis of workers who have contact with solid urban waste, as well as populations exposed to different environmental matrices contaminated by these effluents.

Some organic recalcitrant compounds are not degraded by conventional water treatment systems, making necessary the use of advanced technologies to eliminate these substances. Advanced Oxidation Processes (AOPs) have been extensively proposed to remove emerging contaminants aiming potable water reuse, but literature barely addresses neurotoxic effects of AOPs residual byproducts. These processes involve high costs associated with the electricity, maintenance and oxidizing agent used. However, electrochemical AOPs are techniques based on electron transfer, thus being a clean form of energy and very efficient in the degradation of organic pollutants. Parabens are naturally found in plant sources but most are chemically synthesized, requiring careful treatment to not disturb the environment. In this study, a mixture of parabens (10 mg L−1 each) was degraded by an electrochemical oxidation (EO) system with a Ti/Pt anode. Some parameters, such as the current density (25, 75 and 125 A m−2) and the electrolyte type and concentration (1.5, 3.0 and 5.0 g NaCl L−1 and 3.0 g Na2SO4 L−1) were changed. The best results were obtained with 125 A m−2 and 3.0 g NaCl L−1, which led to the complete degradation of the parabens present in the mixture, after 10 min. In addition to these studies neurotoxicity tests were also performed using the solutions of interest, before and after the EO treatment. It was observed, using the reactive oxygen species (ROS) fluorescent indicator H2DCFDA, that the non-treated solution caused an increase in ROS formation with a signal amplitude of 0.84 ± 0.20 above the baseline. After the EO process the parabens mixture did not lead to a significant ROS change.The solution to bridge the problem of high electricity costs may be replacing it with solar energy, low cost catalysts and other treatment processes involving renewable and eco-friendly energy. Keywords: Bioenergy, Advanced oxidative process (AOPs), Contaminants of emerging concern (CECs), Hippocampal slices, Neurotoxicity, Reactive oxygen species (ROS)

Rare Earth Elements (REE) are becoming increasingly important economically and highly exploited, thus contributing to REE increases in ecosystems. The ecotoxicological effects of REE on the terrestrial environment are, however, not fully understood and information on the biological effects of REE is urgently required for environmental risk assessments. In this review, studies and gaps in the existing scientific literature regarding the toxicological effects of REE on terrestrial organisms are presented. A total of 41 articles from the Web of Science database are discussed. La and Ce are the most studied elements, while little information is found concerning heavy REE. Most studies have been performed on plant species and few investigations are available for animals. Plant effects such as reduced mitotic index, germination and photosynthesis and antioxidant system enzyme alterations have been reported. Invertebrate effects include mortality, reproduction alterations and reduced locomotion. Based on the limited number of articles on terrestrial environment REE effects, this review highlights the need for more detailed studies in order to elucidate the effects associated with the REE hormesis and perform complete risk assessments with the establishment of safe REE usage limits.

Leachate is a variable effluent from waste management systems generated during waste collection and on landfills. Twenty-two leachate samples from waste collection trucks and a landfill were collected from March to December 2019 in the municipality of Rio de Janeiro (Brazil) and were analyzed for Human Adenovirus (HAdV), bacterial indicators and physico-chemical parameters. For viral analysis, samples were concentrated by ultracentrifugation and processed for molecular analysis using QIAamp Fast DNA Stool mini kit® for DNA extraction followed by nested-PCR and qPCR/PMA-qPCR TaqMan® system. HAdV was detected by nested-PCR in 100% (9/9) and 83.33% (12/13) of the truck and landfill leachate samples, respectively. Viral concentrations ranged from 8.31 × 10

Recently, chlorination disinfection technology applying ultraviolet radiation (Cl/UV) has received attention as an advanced oxidative process (AOP) for the generation of highly oxidant species. Many studies have evaluated its effects on pathogen inactivation, contaminant removal, and formation of disinfection by-products (DBPs). However, the degradation of three endocrine disruptor chemicals (EDCs), 17β-estradiol (E2), 17α-ethinylestradiol (EE2), and bisphenol-A (BPA), associated with simultaneous disinfection and estrogenic activity and ecotoxicity assessments has not yet been reported. Compound degradation increased with increasing chlorine concentrations (2 mg·L-1 chlorine), with pseudo-first-order kinetics 1.86×10−2 s-1, 3.06×10−2 s-1, and 3.09×10−2 s-1 for BPA, E2, and EE2, respectively. The degradation kinetics in a WWTP effluent significantly decreased to 4.94×10−2 min-1, 4.75×10−2 min-1, and 4.84×10−2 min-1, for BPA, E2, and EE2, respectively. However, 45% TOC removal and disinfection of E. coli and total coliform bacteria (TCB) were observed in 10 min of treatment. The yeast estrogen screen (YES) revealed that the treatment did not form by-products with estrogenic activity, demonstrating cleavage or mineralization in the phenolic group, common to all assessed compounds. High cell growth inhibition and mortality for Raphidocelis subcapitata and Ceriodaphnia dubia, respectively, were observed during the photodegradation process. Thus, the formed DBPs may be responsible for the observed toxicity and should be taken into account in WWTP treatments in order to monitor the formation of chlorinated by-products.

Poultry litter is widely applied as a fertilizer even though it is one of the main antibiotic sources for agricultural soils. Long-term sublethal effects (56 days) on the antioxidant system of Eisenia andrei earthworms following exposure to fluoroquinolone-contaminated poultry litter (enrofloxacin + ciprofloxacin) at 5.0, 10 and 20 g kg-1 were evaluated. The following biomarkers were assessed: superoxide dismutase (SOD), catalase (CAT), glutathione-S-trasferase (GST), reduced glutathione (GSH) and a lipid peroxidation (LPO) proxy. Significant CAT and SOD increases and a moderate positive correlation (ρ = 0.67, p < 0.05) between these enzymes was observed. Glutathione-S-trasferase levels increased significantly at 10 g kg-1, while GSH exhibited a dose-dependent response at 5.0 mg kg-1 (4 - 106%), 10 mg kg-1 (28 - 330 %) and 20 mg kg-1 (45 - 472%). LPO levels exhibited a decreasing trend with increasing poultry litter concentrations of 8 - 170% (5.0 g kg-1), 7 - 104% (10 mg kg-1) and 3 - 6% (20 mg kg-1). A Principal Component Analysis (PCA) highlighted increased SOD and CAT activities, possibly due to increases in reactive oxygen species (ROS) concentrations. Biological Health Status assessments based on the Biomarker Response Index indicate major alterations in the first month of exposure, changing to moderate in the second month. These findings indicate an antioxidant system attenuation trend. It is possible, however, that successive poultry litter applications may reduce the long-term recovery capacity of the evaluated biomarkers.

Poultry litter is widely applied as a fertilizer even though it is one of the main antibiotic sources to agricultural soils. Long-term sublethal effects (56 days) on the antioxidant system of Eisenia andrei earthworms following exposure to fluoroquinolone-contaminated poultry litter (enrofloxacin + ciprofloxacin) at 5.0, 10, and 20 g kg

The massive consumption of different organic substances and their release through various pathways into the environment constitute an emerging environmental problem that poses serious threats to public health. Micropollutants discharged in domestic wastewaters, which pharmaceuticals and personal care products have been received scientific interest potentially dangerous to environment. Current wastewater treatment plants are not designed to remove pharmaceuticals compounds, since they are not treatment targets. Advanced oxidation processes are efficient methodology for the degradation of organic compounds in the environmental matrices. We reviewed more than 100 papers about heterogeneous and homogenous advanced oxidation processes for the removal personal care products and pharmaceuticals compounds. Advanced oxidation processes have been an alternative to remove micropollutants from wastewater. Ozonation is the most appropriate for the treatment of different kinds of wastewater (42% of papers). Chlorine with ultraviolet is the less studied (6.4%) however is the fastest process to remove the compounds. Toxicity evaluation during the oxidation process is an important tool to assess possible effects of by-product to human and environment health.

Poultry litter is one of the main sources of fluoroquinolones (FQs) in agricultural soils. In this study, our main goal was to investigate FQ-contaminated poultry litter effects on Eisenia andrei earthworms. To achieve this, acute and chronic tests covered several endpoints, such as avoidance, biomass, lethality, reproduction and changes to immune cells. FQs (enrofloxacin and ciprofloxacin) were determined in a poultry litter sample through high performance liquid chromatography with a fluorescence detector. The avoidance test indicates that poultry litter strongly repels earthworms, even at the lowest concentration (50 g kg−1). In the acute test, the lethal concentration of poultry litter to 50% of the earthworms (LC50), was estimated at 28.5 g kg−1 and a significant biomass loss (p

Leachate is difficult to biodegrade, and presents variable physical, chemical and biological characteristics, as well as high toxicological potential for soil, groundwater and water bodies. In this context, untreated leachate toxicity was evaluated through acute and chronic exposures in Eisenia andrei earthworms. Physico-chemical leachate characterizations indicate a complex composition, with high organic matter (COD – 10,634 mg L−1) and ammoniacal nitrogen (2388 mg L−1) concentrations. Metals with carcinogenic potential, such as Cr, As and Pb, were present at 0.60, 0.14 and 0.01 μg L−1, respectively and endocrine disrupting compounds were detected in estradiol equivalents of 660 ± 50 ng L−1. Acute tests with Eisenia andrei indicated an LC50 (72 h) of 1.3 ± 0.1 μL cm−2 in a filter paper contact test and 53.9 ± 1.3 mL kg−1 in natural soil (14 days). The EC50 in a behavioral test was estimated as 31.6 ± 6.8 mL kg−1, indicating an escape effect for concentrations ranging from 35.0 to 70.0 mL kg−1 and habitat loss from 87.5 mL kg−1 of leachate exposure. Chronic exposure (56 days) led to reproduction effects, resulting in a 4-fold decreased cocoon production and 7-fold juvenile decrease. This effect was mainly attributed to the possible presence of endocrine disrupting compounds. An estimated NOAEL of 1.7 mL L−1 and LOAEL of 3.5 mL L−1 were estimated for earthworms exposed to the assessed effluent. Extremely high-risk quotients (RQ ≥ 1) were estimated based on leachate application in irrigation. Thus, adequate municipal solid waste management is paramount, especially with regard to generated by-products, which can result in high toxicological risks for terrestrial organisms.

BackgroundThe Rio Doce estuary, in Brazil, was impacted by the deposition of iron mine tailings, caused by the collapse of a dam in 2015. Based on published baseline datasets, the estuary has been experiencing chronic trace metal contamination effects since 2017, with potential bioaccumulation in fishes and human health risks. As metal and metalloid concentrations in aquatic ecosystems pose severe threats to the aquatic biota, we hypothesized that the trace metals in estuarine sediments nearly two years after the disaster would lead to bioaccumulation in demersal fishes and result in the biosynthesis of metal-responsive proteins.MethodsWe measured As, Cd, Cr, Cu, Fe, Mn, Pb, Se and Zn concentrations in sediment samples in August 2017 and compared to published baseline levels. Also, trace metals (As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, Se and Zn) and protein (metallothionein and reduced glutathione) concentrations were quantified in the liver and muscle tissues of five fish species (Cathorops spixii,Genidens genidens,Eugerres brasilianus,Diapterus rhombeusandMugilsp.) from the estuary, commonly used as food sources by local populations.ResultsOur results revealed high trace metal concentrations in estuarine sediments, when compared to published baseline values for the same estuary. The demersal fish speciesC. spixiiandG. genidenshad the highest concentrations of As, Cr, Mn, Hg, and Se in both, hepatic and muscle, tissues. Trace metal bioaccumulation in fish was correlated with the biosynthesis of metallothionein and reduced glutathione in both, liver and muscle, tissues, suggesting active physiological responses to contamination sources. The trace metal concentrations determined in fish tissues were also present in the estuarine sediments at the time of this study. Some elements had concentrations above the maximum permissible limits for human consumption in fish muscles (e.g., As, Cr, Mn, Se and Zn), suggesting potential human health risks that require further studies. Our study supports the high biogeochemical mobility of toxic elements between sediments and the bottom-dwelling biota in estuarine ecosystems.

Marine bivalves have been widely applied as environmental contamination bioindicators, although studies concerning tropical species are less available compared to temperate climate species. Assessments regarding Perna perna mytilid mussels, in particular, are scarce, even though this is an extremely important species in economic terms in tropical countries, such as Brazil. To this end, Perna perna mytilids were sampled from two tropical bays in Southeastern Brazil, one anthropogenically impacted and one previously considered a reference site for metal contamination. Gill metallothionein (MT), reduced glutathione (GSH), carboxylesterase (CarbE) and lipid peroxidation (LPO) were determined by UV− vis spectrophotometry, and metal and metalloid contents were determined by inductively coupled plasma mass spectrometry (ICP− MS). Metalloprotein metal detoxifi cation routes in heat-stable cellular gill fractions were assessed by size exclusion high performance chroma tography (SEC− HPLC) coupled to an ICP− MS. Several associations between metals and oxidative stress endpoints were observed at all four sampling sites through a Principal Component Analysis. As, Cd, Ni and Se contents, in particular, seem to directly affect CarbE activity. MT is implicated in playing a dual role in both metal detoxification and radical oxygen species scavenging. Differential SEC− HPLC− ICP− MS metal-binding profiles, and, thus, detoxification mechanisms, were observed, with probable As-, Cu- and Ni-GSH complexa tion and binding to low molecular weight proteins. Perna perna mussels were proven adequate tropical bio indicators, and further monitoring efforts are recommended, due to lack of data regarding biochemical metal effects in tropical species. Integrated assessments, as performed herein demonstrate, are invaluable in evaluating contaminated aquatic environments, resulting in more accurate ecological risk assessments.

Contaminants of emerging concern (CECs) are released daily into surface water, and their recalcitrant properties often require tertiary treatment. Electrochemical oxidation (EO) is often used as an alternative way to eliminate these compounds from water, although the literature barely addresses the neurotoxic effects of residual by-products. Therefore, this study investigated the performance of EO in the removal of five CECs (alprazolam, clonazepam, diazepam, lorazepam, and carbamazepine) and performed neurotoxicity evaluations of residual EO by-products in Wistar rat brain hippocampal slices. Platinum-coated titanium (Ti/Pt) and boron-doped diamond (BDD) electrodes were studied as anodes. Different current densities (13-75 A m

The Rio Doce estuary in Brazil was impacted by the deposition of mine tailings caused by the collapse of a mining dam in 2015. Since the disaster, the estuary is experiencing chronic trace metal contamination effects, but potential trace metal accumulation in fishes has not been reported. Trace metals in aquatic ecosystems pose severe threats to the aquatic biota, so we hypothesized that the accumulation of trace metals in estuarine sediments nearly two years after the disaster would cause contaminant bioaccumulation, resulting in the biosynthesis of metal-responsive proteins in fishes. We determined trace metal concentrations in sediment samples, metal concentrations, and quantified stress protein concentrations in the liver and muscle tissue of five different fish species in the estuary. Our results revealed high concentrations of trace metals in estuarine sediments when compared to published baseline values for this estuary. The demersal fish species Cathorops spixii and Genidens genidens had the highest Hg, As, Se, Cr, and Mn concentrations in both hepatic and muscle tissues. Metal bioaccumulation in fish was statistically correlated with the biosynthesis of metallothionein and reduced glutathione in both fish liver and muscle tissue. The trace metals detected in fish tissues resemble those in the contaminated sediments present at the estuary at the time of this study and were also significantly correlated to protein levels. Trace metals in fish muscle were above the maximum permissible limits for human consumption, suggesting potential human health risks that require further determination. Our study supports the high biogeochemical mobility of trace metals between contaminated sediments and local biota in estuarine ecosystems.

Extensive use of endocrine disruptor compounds (EDCs) and their release through various pathways into the environment are emerging environmental concerns. In this context, H

Contaminants of emerging concern (CEC) are routinely detected in aquatic environments, especially pharmaceuticals, such as carbamazepine (CBZ), and neonicotinoid pesticides, like acetamiprid (ACT). CECs can interact with each other and with other legislated contaminants like Cd, resulting in unknown effects. Most studies evaluate only the effects of single contaminant exposures on aquatic biota. Therefore, the aim of the present study was to assess the effects of both single and combined CBZ, ACT and Cd exposures on zebrafish brain and liver oxidative stress parameters and metal homeostasis. The biomarkers catalase (CAT), glutathione-S-transferase (GST), total thiols (TOT), metallothionein (MT) and malondialdehyde (MDA) and the essential elements Ca, Cu, K, Na, Mg, Mn and Zn were evaluated after 96-hour static exposures. CBZ, ACT and Cd single (brain and liver) and combined (liver) treatments resulted in oxidative effects in both fish organs, also leading to metal (Ca, Mg, K, Mn, Zn and Cu) homeostasis alterations. ACT exposure resulted in the greatest adverse effects in the brain, while CBZ was the cause of major element homeostasis and oxidative stress alterations in the liver. Lower LPO levels were observed in the combined treatments compared to single treatments, suggesting interactions and contaminant effect attenuation. This study is the first to evaluate the initial effects of combined CBZ, ACT and Cd exposures in zebrafish, paving the way for further investigations concerning other biomarkers during longer exposure times.

The dispersion of pollutants and proliferation of antibiotic resistant bacteria in the aquatic environment are an emerging health concern worldwide. In this sense, it is essential to develop new technologies to increase the quality of wastewater treatment, which is spread throughout the environment. The present study has demonstrated evidence of the existence of antibiotic and mercury-resistant bacteria in the aquatic environment. The application of heterogeneous photocatalysis with UVA/TiO2 P25 slurry (200 mg L−1), UVA/TiO2-immobilized, and UVA/TiO2-immobilized/H2O2 were evaluated for the simultaneous elimination of a mixture of contaminants of emerging concern (acetamiprid (ACP), imazalil (IMZ) and bisphenol A (BPA)) and inactivation of antibiotic and mercury-resistant bacteria (Pseudomonas aeruginosa and Bacillus subtilis). UVA/TiO2-immobilized/H2O2 increased the inactivation and elimination of the contaminants. After the combined treatment, the mixture of BPA, IMZ and ACP decreased 62%, 21% and

Pharmaceutically active compounds are carried into aquatic bodies along with domestic sewage, industrial and agricultural wastewater discharges. Psychotropic drugs, which can be toxic to the biota, have been detected in natural waters in different parts of the world. Conventional water treatments, such as activated sludge, do not properly remove these recalcitrant substances, so the development of processes able to eliminate these compounds becomes very important. Advanced oxidation processes are considered clean technologies, capable of achieving high rates of organic compounds degradation, and can be an efficient alternative to conventional treatments. In this study, the degradation of alprazolam, clonazepam, diazepam, lorazepam, and carbamazepine was evaluated through TiO2/UV-A, H2O2/UV-A, and TiO2/H2O2/UV-A, using sunlight and artificial irradiation. While using TiO2 in suspension, best results were found at [TiO2] = 0.1 g L−1. H2O2/UV-A displayed better results under acidic conditions, achieving from 60 to 80% of removal. When WWTP was used, degradation decreased around 50% for both processes, TiO2/UV-A and H2O2/UV-A, indicating a strong matrix effect. The combination of both processes was shown to be an adequate approach, since removal increased up to 90%. H2O2/UV-A was used for disinfecting the aqueous matrices, while mineralization was obtained by TiO2-photocatalysis.

It is estimated that approximately 0.4% of the total leachate produced in a landfill is destined for treatment plants, while the rest can reach the soil and groundwater. In this context, this study aimed to perform leachate toxicity evaluations through immune system cytotoxic assessments, genotoxic (comet assay) appraisals and antioxidant system (superoxide dismutase - SOD; catalase - CAT, glutathione-S-transferase - GST; reduced glutathione - GSH and metallothionein - MT) evaluations in Eisenia andrei earthworms exposed to a Brazilian leachate for 77 days. The leachate sample contained high organic matter (COD - 10,630 mg L−1) and ammoniacal nitrogen (2398 mg L−1), as well as several metals, including Ca, Cr, Fe, Mg, Ni and Zn. Leachate exposure resulted in SOD activity alterations and increased CAT activity and MT levels. Decreased GST activity and GSH levels were also observed. Antioxidant system alterations due to leachate exposure led to increased malondialdehyde levels as a result of lipid peroxidation after the 77 day-exposure. An inflammatory process was also observed in exposed earthworms, evidenced by increased amoebocyte density, and DNA damage was also noted. This study demonstrates for the first time that sublethal effect assessments in leachate-exposed earthworms comprise an important tool for solid waste management.

The Indigo carmine (IC) dye has been widely used in textile industries, even though it has been considered toxic for rats, pigs and humans. Owing to its toxicity, wastes containing this compound should be treated to minimize or eliminate their toxic effects on the biota. As an alternative to wastewater treatment, advanced oxidative processes (AOPs) have been highlighted due to their high capacity to destruct organic molecules. In this context, this study aimed to evaluate Indigo Carmine toxicity to soil organisms using the earthworm Eisenia andrei as a model-organism and also verify the efficiency of AOP in reducing its toxicity to these organisms. To this end, lethal (mortality) and sub-lethal (loss or gain of biomass, reproduction, behavior, morphological changes and immune system cells) effects caused by this substance and its degradation products in these annelids were evaluated. Morphological changes were observed even in organisms exposed to low concentrations, while mortality was the major effect observed in individuals exposed to high levels of indigo carmine dye. The organisms exposed to the IC during the contact test showed mortality after 72h of exposure (LC50 = 75.79mgcm-2), while those exposed to photoproducts showed mortality after 48h (LC50 = 243min). In the chronic study, the organisms displayed a mortality rate of 14%, while those exposed to the photoproduct reached up to 32.7%. A negative influence of the dye on the reproduction rate was observed, while by-products affected juvenile survival. A loss of viability and alterations in the cellular proportion was verified during the chronic test. However, the compounds did not alter the behavior of the annelids in the leak test (RL ranged from 20% to 30%). Although photocatalysis has been presented as an alternative technology for the treatment of waste containing the indigo carmine dye, this process produced byproducts even more toxic than the original compounds to E. andrei.

Triclocarban (TCC) is an antibacterial agent found in pharmaceuticals and personal care products (PPCP). It is potentially bioaccumulative and an endocrine disruptor, being classified as a contaminant of emerging concern (CEC). In normal uses, approximately 96% of the used TCC can be washed down the drain going into the sewer system and eventually enter in the aquatic environment. UV photolysis can be used to photodegrade TCC and ecotoxicity assays could indicate the photodegradation efficiency, since the enormous structural diversity of photoproducts and their low concentrations do not always allow to identify and quantify them. In this work, the TCC was efficiently degraded by UVC direct photolysis and the ecotoxicity of the UV-treated mixtures was investigated. Bioassays indicates that Daphnia similis (48 h EC50 = 0.044 μM) was more sensitive to TCC than Pseudokirchneriella subcapitata (72 h IC50 = 1.01 μM). TCC and its photoproducts caused significant effects on Eisenia andrei biochemical responses (catalase and glutathione-S-transferase); 48 h was a critical exposure time, since GST reached the highest activity values. UVC reduced the TCC toxic effect after 120 min. Furthermore, TCC was photodegraded in domestic wastewater which was simultaneously disinfected for total coliform bacterial (TCB) (360 min) and Escherichia coli (60 min). Graphical abstract TCC degradation and ecotoxicological assessment.

The first-line chemotherapy treatment for Glioblastoma (GBM) - the most aggressive and frequent brain tumor - is temozolomide (TMZ). The Sonic hedgehog (SHH) pathway is involved with GBM tumorigenesis and TMZ chemoresistance. The role of SHH pathway inhibition in the potentiation of TMZ's effects using T98G, U251, and GBM11 cell lines is investigated herein. The combination of GANT-61 and TMZ over 72 hr suggested a synergistic effect. All TMZ-resistant cell lines displayed a significant decrease in cell viability, increased DNA fragmentation and loss of membrane integrity. For T98G cells, G2 /M arrest was observed, while U251 cells presented a significant increase in reactive oxygen species production and catalase activity. All the cell lines presented acidic vesicles formation correlated to Beclin-1 overexpression. The combined treatment also enhanced GLI1 expression, indicating the presence of select resistant cells. The selective inhibition of the SHH pathway potentiated the cytotoxic effect of TMZ, thus becoming a promising in vitro strategy for GBM treatment.

Contaminant such as pesticides, veterinary products, industrial compounds, food additives, personal care products, and pharmaceuticals may cause a negative effect when comes into contact with the environment. The presence of these compounds can be generated toxic effects in the aquatic system and cause an irreparable ecological alteration. Antibiotic compounds are one of the main pollutants found in the aquatic systems, because they are often inadequately prescribed and as a part of antibiotics is not completely consumed or degraded in human and animal bodies. Their residues can be entered in aquatic systems by wastewater treatment plants. The presences of antibiotics in aquatic systems have been linked to increasing microorganism antibiotic resistance through different mutations. Advanced oxidation processes have been proposed for the treatment of antibiotic in aqueous systems, including solar photocatalysis. Several parameters are necessary to take into account in solar photocatalysis treatment to eliminate antibiotics, since these compounds display different physicochemical and biological properties. This chapter discusses the effect of parameters and pathways (transformation products) of solar photocatalysis of antibiotic groups usually found in aquatic systems as macrolides, sulfones, lincosamides, and quinolone.

Extensive use of endocrine disruptor compounds (EDCs) and their release through various pathways into the environment are emerging environmental concerns. In this context, H2O2 and chlorine UV-based treatments were carried out to evaluate their efficiency in the removal of the bisphenol A (BPA), 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) at 100 μg L−1 from ultrapure water and from wastewater treatment plants (WWTP). Photolysis was performed under different irradiation sources, i.e. UVC and UVA. The effect of H2O2 (3 and 30 mg·L−1), free chlorine concentrations (1 and 2 mg·L−1) and pH (5, 7 and 9) were also investigated. Toxicity (Raphidocelis subcapitata) and estrogenic activity (yeast estrogen screen - YES assay) were assessed during the processes. Compound removal at optimal operating parameters reached 100% after 15 and 2 min for UVC/H2O2 (pH 9 and 3 mg L−1 of H2O2), and UVC/Cl (pH 9 and 2 mg L−1 of chlorine), respectively. Total organic carbon (TOC) removal achieved 37% and 45% for the H2O2 and Cl-UV based process, respectively. The in vitro YES assay indicated that the formed by-products were non-estrogenic compounds, while the toxicity evaluation revealed high cell growth inhibition due to UVC/Cl byproducts. During the UV-based processes, 30 transformation products (TPs) were identified, in which three new chlorinated TPs from E2 and EE2 may be responsible for toxicity effects. EDC degradation by UV/Cl is faster than by UV/H2O2, although chlorinated toxic byproducts were also formed during the UV/Cl process.

Triclocarban (TCC) is a contaminant of emerging concern widely applied as an antimicrobial in personal care products and introduced into the terrestrial environment through the application of biosolids (i.e., treated sewage sludge) in agriculture. Displaying the potential to bioaccumulate in the food chain and a high half-life in the soil, the presence of this compound in the environment may lead to potential ecological risks. In this context, TCC toxicity assessments in Eisenia andrei earthworms were carried out through acute, avoidance and chronic tests following cytotoxicity, antioxidant system, i.e. acatalase (CAT), glutathione-S-transferase (GST), glutathione (GSH), lipid peroxidation (LPO), and DNA damage (comet assay) evaluations. An LC50 of 3.3 ± 1.6 mg cm−2 in the acute contact test and an EC50 of 1.92 ± 0.31 mg kg−1 in the avoidance test during 72 h and 48 h, respectively, were obtained. The behavioral test indicates earthworm avoidance from 15.0 mg kg−1 of TCC. During chronic soil exposure, a 44% reduction in earthworm cell viability was observed after 14 days of exposure to 10 mg kg−1 TCC, while an increase in the percentage of amoebocyte cells also ocurred. Chronic exposure to TCC led to reduced CAT and GST activities, decreased GSH levels and increased LPO in exposed organisms. DNA damage was observed after 45 days from a 1 mg kg−1 dose of TCC. Therefore, TCC exhibits toxicological potential to Eisenia andrei earthworms, mainly during long-term exposures. This study provides mechanistic earthworm information towards understanding the environmental and human health implications of TCC exposure and draws attention to correct biosolid management.

Contaminants of emerging concern have become an important environmental problem, especially pharmaceutically active compounds (PhACs), since, after use, these drugs return to the environment, contaminating aquatic ecosystems. Some may display the ability to bioaccumulate and biomagnify throughout the food chain, leading to potential environmental and human deleterious effects which are, however, still largely unknown. In this context, the aim of the present study was to evaluate the effect of two psychotropic drugs commonly found in the environment, carbamazepine (CBZ) and clonazepam (CZP), both isolated and co-administrated, on oxidative stress biomarkers and essential metal homeostasis in Danio rerio fish specimens. No studies are available to data in this regard concerning CZP effects on fish. Reduced Glutathione (GSH), Metallothionein (MT), Catalase (CAT) and Glutathione S-Transferase (GST) were determined, as well as essential metals in fish liver, kidney and brains. Significant oxidative stress effects were observed for several biomarkers, where brain GST activity was the most affected, mainly with regard to CBZ exposure, while GST and CAT activity in the liver were downregulated in the co-administration mixture. In addition, dishomeostasis of several essential elements was detected in all analyzed organs, with a synergistic action of CBZ and CZP in brain, decreasing basal Mg, Al, K, Fe, Co, Ni and Cu levels in this organ, the target site for these drugs in humans. The brain organ was the most affected as observed by altered GST activity and metal dyshomeostasis concerning exposure to both compounds. These compounds, thus, present health risks to the aquatic biota, due to the evidenced deleterious effects and their constant release into the environment due to widespread use. Steps are needed to implement adequate legislation for risk analysis and decision-making in order to mitigate the effects of these emerging contaminants on aquatic ecosystem health.

The aim of this study was to analyze the photocatalytic degradation of C.I. Food Blue 1 under artificial and solar irradiation using titanium dioxide and to evaluate the ecotoxicity of the photodegradation products in organisms of two different food chain levels. Three different artificial-light and geometric photoreactors were evaluated for the ideal amount of catalyst and UV-light time irradiation. The optimized experiments were performed in a solar compound parabolic collector pilot plant with different water matrices (distilled water, freshwater, synthetic and real MWWTP) at Plataforma Solar de Almeria. Photodegradation of the indigo dye was followed by UV–Vis spectroscopy, high performance liquid chromatography, total organic carbon and ion chromatography. Solar pilot plant photocatalysis was efficient for different water matrices but the photodegradation was found to be somewhat slower for the more complex matrixes. Ecotoxicological evaluation with Daphnia similis and Pseudokirchneriella subcapitata showed that photodegradation products were more toxic than untreated indigo carmine and that titanium residues affected the two tested species.

Thousands of compounds are used and disposed of every day and many of them are not degraded in conventional treatment plants. It is necessary an alternative to eliminate these compounds. This can be done through electrooxidation technology, which was applied in this work to a mixture of pharmaceutical compounds including alprazolam (ALP), clonazepam (CLP), diazepam (DZP), lorazepam (LZP) and carbamazepine (CBZ) at 100 µg.L-1. The mixture was studied with different types of electrolytes and the neurotoxic effect of the treatment was evaluated. The best result was obtained with NaCl (0.5 g.L-1), leading to complete degradation of CLP, LZP and CBZ.

The photocatalytic degradation of three textile azo dyes, Remazol Yellow Gold RGB, Remazol Blue RGB and Remazol Carbon RGB has been studied in model effluents regarding the variation of parameters as concentration of titanium dioxide (TiO2), concentration of the dyes, effect of hydrogen peroxide (H2O2), effect of pH, recycling of TiO2. The concentration of 1 g L−1 of TiO2 degraded around 100 % of Remazol Blue RGB and Remazol Carbon RGB and around 90 % for the Remazol Yellow Gold RGB after 120 min of photodegradation. The remaining concentrations of added TiO2 were found to be less efficient, except for Remazol Blue RGB, which still reaches about 80 % photodegradation, for 0.1 g L−1 of TiO2. The efficiency of photodegradation of all dyes decreased with an increase of the initial dye concentration. For a concentration of 30 mg L−1, all dyes showed around 100 %. However, upon increasing the concentration of the dye until 150 mg L−1, the photodegradation becomes very slow, with photodegradation rates off only 11 % for Remazol Yellow Gold RGB and Remazol Blue RGB and 9.7 % for the Remazol Carbon RGB. Photodegradation of the three dyes was found to be pH dependent. The maximum reaction rate was observed with 0.3 × 10−3 mol L−1 of H2O2 for the three azo dyes (achieving more than 90 % of degradation in 120 min). At higher concentrations of H2O2, the degradation efficiency decreased significantly for all dyes. In what regards the reuse of the photocatalyst, the first cycle degraded 100 % of the Remazol Carbon RGB after 60 min of irradiation and the second and third cycles degraded 44 and 36 % of the dye. The effect of the simultaneous photodegradation of the three azo dyes in water was further investigated for distilled and natural lake water. It was observed that the degradation rates achieved in mono and three-component system were identical. The degradation yield in lake water observed to be smaller than in distillated water with 75, 72 and 53 % (99, 98 and 88 % in distilled water) of degradation for Remazol Blue RGB, Remazol Carbon RGB and Remazol Yellow Gold RGB, respectively.

BACKGROUND Thiabendazole, imazalil and acetamiprid, pesticides found in wastewater in the citrus fruit processing industry, are recalcitrant to biological treatments. This study deals with the preparation of TiO2 supported on glass beads and its use as a photocatalyst in a compound parabolic collector (CPC) solar reactor for the elimination of a mixture of these pesticides (100 µg L−1 each) in different water matrices. RESULTS The TiO2 supported catalyst prepared exhibited good mechanical stability and photocatalytic activity with acetaminophen as the test compound, even in complex matrices. Imazalil degradation was complete, regardless of the type of water, but strong influence of the matrix was oberved in the photocatalytic degradation of thiabendazol and acetamiprid. CONCLUSIONS The TiO2-coated glass spheres showed good performance after five cycles in a real municipal wastewater treatment plant (MWWTP) secondary effluent. Both the type of water and the nature of the pollutant play an important role in photocatalytic degradation efficiency. The main photogenerated species involved in the photocatalytic degradation of each pesticide in distilled water were identified. © 2013 Society of Chemical Industry

The neonicotinoid acetamiprid has been suggested as a worldwide substitute for organophosphates, due to its lower toxicity. The present study assessed several acetamiprid effects on Eisenia andrei earthworms in acute contact (ranging from 1.6 × 10−5 to 0.16 μg cm−2 acetamiprid), behavioral (0.1, 0.5, 1 mg kg−1) and chronic (0.001, 0.01, 0.05 and 0.1 mg kg−1 acetamiprid) assays carried out in natural soil. Reproduction, cytotoxicity (coelomocyte density and viability), immune cell typing (eleocytes and amoebocytes) and antioxidant defense system (glutathione (GSH), catalase (CAT) and glutathione S-transferase (GST)) responses were determined. The LC50 in the acute contact test was calculated as 1.86 × 10−2 μg cm−2. Acetamiprid concentrations of 0.5 and 1 mg kg−1 led to earthworm avoidance responses (NR = 61.09 ± 10.01%) and habitat loss (NR = 78.02 ± 12.03%), respectively. Reproduction was also affected, with a decreased number of cocoons and hatchlings per cocoon observed at 0.05 and 0.1 mg kg−1. Amoebocytes were the predominant immune system cells during the 15th and 30th assay days, while eleocytes were the main cells observed at the 45th day. CAT activities on the 30th and 45th day of exposure were increased at the lowest acetamiprid concentrations (0.001 and 0.01 mg kg−1) and decreased with increasing pesticide concentration (0.05 and 0.1 mg kg−1). Maximum GST activities and GSH levels were noted at 0.01 mg kg−1 acetamiprid. However, increasing concentrations led to GST inhibition, while GSH levels were maintained. A long-term acetamiprid exposure affected earthworm reproduction, behavior and immune and antioxidant systems, which could affect the ecological soil balance and, consequently, the entire food chain.

A CuO + TiO2 mixture, based on two commercial and well characterized CuO and TiO2 photocatalyst, has been used to produce hydrogen by solar light irradiation and in presence of different organic compounds (methanol, glycerol, formic acid, and the components of a wastewater coming from the biodiesel industry) acting as sacrificial electron donors. The experiments have been conducted at Plataforma Solar de Almeria (PSA, south of Spain) with a pilot plant scale reactor using a CPC (compound parabolic collector) configuration. The tested system has shown similar hydrogen generation capacity and energy efficiency than more expensive ones based on the use of noble metal/photocatalyst composites. Formic acid has shown to be the most effective electron donor, although very close amounts of hydrogen are also produced with glycerol, and this is found as a waste compound released in large quantities at the biodiesel industry wastewaters. As seen in previous similar studies, the increase of solution conductivity hampers the hydrogen generation, and a slightly basic solution pH (pH≈9) gives the best reaction conditions. Finally, the composite can be recovered and successfully reused giving the ensuing and sustained generation of H2 while removing more than 50% of TOC.

The Indigo carmine (IC) dye has been widely used in textile industries, even though it has been considered toxic for rats, pigs and humans. Owing to its toxicity, wastes containing this compound should be treated to minimize or eliminate their toxic effects on the biota. As an alternative to wastewater treatment, advanced oxidative processes (AOPs) have been highlighted due to their high capacity to destruct organic molecules. In this context, this study aimed to evaluate Indigo Carmine toxicity to soil organisms using the earthworm Eisenia andrei as a model-organism and also verify the efficiency of AOP in reducing its toxicity to these organisms. To this end, lethal (mortality) and sub-lethal (loss or gain of biomass, reproduction, behavior, morphological changes and immune system cells) effects caused by this substance and its degradation products in these annelids were evaluated. Morphological changes were observed even in organisms exposed to low concentrations, while mortality was the major effect observed in individuals exposed to high levels of indigo carmine dye. The organisms exposed to the IC during the contact test showed mortality after 72h of exposure (LC

Organic dyes constitute one of the largest groups of wastewater’s pollutants. In general, they are released into the environment by textile industries. Approximately 100,000 dyes are widely used in the textile industry, and a large wastewater of dyestuff is generated annually. Among these, indigoid class is commercial dyes used mostly for cotton cloth dyeing. Indigo carmine (IC) is also one of the oldest dyes and still one of the most used in textile industry and is considered as a very toxic indigoid dye. Most toxic dyes are recal‐ citrant to biodegradation, causing a decrease in the efficiency of biological wastewater treatment plants. Titanium dioxide is a well-known photocatalyst mostly used in suspen‐ sions in photoreactions for wastewater treatment. The use of TiO2 has some advantages such as ease of handling, low cost, low toxicity, high photochemical reactivity, and nonspecific oxidative attack ability. In this way, it can promote the degradation of different target organic compounds with little change of operational parameters. The aim of this chapter is to present the different approaches already used in our team for the remedia‐ tion of waters containing IC mainly through heterogeneous photocatalysis with TiO2. Ad‐ sorption over activated carbon (AC) and photocatalytic degradation of IC mediated by titanium dioxide will be revised as well as some studies on the phototoxicity of the pho‐ toproducts with aquatic and terrestrial organisms. This chapter makes a comprehensive approach to the different results on the remediation of model effluents containing IC un‐ dertaken by this team of researchers.

The photocatalytic degradation of two commercial textile azo dyes, namely C.I Reactive Black 5 and C.I Reactive Red 239, has been studied. TiO(2) P25 Degussa was used as catalyst and photodegradation was carried out in aqueous solution under artificial irradiation with a 125 W mercury vapor lamp. The effects of the amount of TiO(2) used, UV-light irradiation time, pH of the solution under treatment, initial concentration of the azo dye and addition of different concentrations of hydrogen peroxide were investigated. The effect of the simultaneous photodegradation of the two azo dyes was also investigated and we observed that the degradation rates achieved in mono and bi-component systems were identical. The repeatability of photocatalytic activity of the photocatalyst was also tested. After five cycles of TiO(2) reuse the rate of colour lost was still 77% of the initial rate. The degradation was followed monitoring the change of azo dye concentration by UV-Vis spectroscopy. Results show that the use of an efficient photocatalyst and the adequate selection of optimal operational parameters may easily lead to a complete decolorization of the aqueous solutions of both azo dyes.