We investigated the production of highly reactive oxygen species (ROS) in solutions undergoing treatment using CaviPlasma (CP) technology. This technology combines plasma discharge with hydrodynamic cavitation. This study focused on factors such as pH, conductivity, presence of salts and organic matter affecting ROS formation and their stability in solutions. Depending on the used matrix, CP produces 450-580 µg L-1 s-1 of hydrogen peroxide and 1.9 µg L-1 s-1 of hydroxyl radicals dissolved in liquid. Using cyanobacteria and cyanotoxins as example, we proved that CP technology is a highly efficient method for destroying microorganisms and persistent toxins. The biocidal effect of the CP treatment was confirmed on two species of cyanobacteria, Synechococcus elongatus and Merismopedia minutissima. The effectiveness of the technology in degrading microcystins was also demonstrated. The potential of this technology is based on its high energy efficiency, G(H2O2) ≈ 10 g kWh-1 and G(O3) ≈ 0.03 g kWh-1 (in deionised water), realistic applicability with throughput rates (> 1 m3 h-1), and comparatively easy scalability system.
- Klíčová slova
- Cyanobacteria, Electric discharge, Hydrodynamic cavitation, Microcystins, Plasma-treated liquid, Radicals, Water treatment,
- MeSH
- dezinfekce * MeSH
- mikrocystiny MeSH
- peroxid vodíku MeSH
- reaktivní formy kyslíku * MeSH
- sinice * MeSH
- Synechococcus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- mikrocystiny MeSH
- peroxid vodíku MeSH
- reaktivní formy kyslíku * MeSH
Saxitoxins (STXs) are potent neurotoxins produced by marine dinoflagellates or freshwater cyanobacteria known to cause acute and eventually fatal human intoxications, which are classified as paralytic shellfish poisonings (PSPs). Rapid analysis of STXs in blood plasma can be used for a timely diagnosis and confirmation of PSPs. We developed a fast and simple method of STX extraction based on plasma sample acidification and precipitation by acetonitrile, followed by quantification using liquid chromatography-tandem mass spectrometry (LC-MS-MS). Our approach provides the results ≤30 min, with a limit of detection of 2.8 ng/mL and a lower limit of quantification of 5.0 ng/mL. Within-run and between-run precision experiments showed good reproducibility with ≤15% values. Standard curves for calibration were linear with correlation coefficients ≥0.98 across the assay calibration range (5-200 ng/mL). In an interlaboratory analytical exercise, the method was found to be 100% accurate in determining the presence or absence of STX in human plasma specimens, with recovery values of 86-99%. This simple method for STX determination in animal or human plasma can quickly and reliably diagnose STX exposures and confirm suspected PSP cases to facilitate patient treatment or expedite necessary public health or security actions.
- MeSH
- chromatografie kapalinová MeSH
- kapalinová chromatografie-hmotnostní spektrometrie * MeSH
- krevní plazma MeSH
- lidé MeSH
- reprodukovatelnost výsledků MeSH
- saxitoxin * MeSH
- tandemová hmotnostní spektrometrie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- saxitoxin * MeSH
The present paper investigated the potential of hydrodynamic cavitation (HC) as an effective tool for activating sodium percarbonate (SPC). The method's efficiency was demonstrated by effectively removing estrogens, which are pollutants that have adverse impacts on aquatic ecosystems. The effects of the SPC concentration, temperature of solution, and cavitation time were evaluated. After SPC/HC treatment, the removal of estrogens was monitored by liquid chromatography-tandem mass spectrometry (LC -MS/MS). Already after 4 s of treatment and 24 h of reaction time, more than 97% of estrogens (initial concentration of 300 ng/L) were removed. The effect of post-treatment time is not considered in several papers, even though it seems to be crucial and is discussed here. The results were supported by the values of degradation rate constants, which fit the pseudo-first-order kinetic model. We also verified that HC alone was not effective for estrogen removal under the selected conditions. The sustainability of the SPC/HC system was evaluated based on electric energy per order calculation. The combination of SPC and HC is a promising approach for rapidly degrading micropollutants such as estrogenic compounds without the need for additional technological steps, such as pH or temperature adjustment.
Fruits of Schisandra chinensis, an East Asian liana plant, are currently more and more used to produce nutrient supplements that positively affect human health due to the content of various secondary metabolites. On the other hand, these substances because of their bioactivity can cause possible allelopathic or toxic effects concerning other organisms (algae, plants, animals). But the ecotoxicological properties of S. chinensis outside its area of origin have yet to be sufficiently verified. Two crustaceans, Daphnia magna and Thamnocephalus platyurus, were selected as model aquatic organisms to test the potential impact of S. chinensis active compounds on the aquatic environment. Crude water extract from S. chinensis fruits, simulating the natural leakage of active substances in water, was tested in treatments from 0.0045 to 45 mg/L (according to the content of schisandrin as the dominating lignan). Effective concentration (EC50) causing 50% lethal effect for D. magna was established to 0.0448 mg/L after 24 h and 0.0152 mg/L after 48 h. EC50 for T. platyurus reached 0.4572 mg/L after 24 h, i.e. more than ten times higher than for D. magna. This study showed that the potential environmentally relevant concentrations of S. chinensis bioactive compounds could represent a severe risk to aquatic ecosystems.
- Klíčová slova
- Acute toxicity, Adaptogen, Lignan, Schisandrin, Zooplankton,
- MeSH
- Anostraca MeSH
- chemické látky znečišťující vodu * toxicita MeSH
- Daphnia MeSH
- ekosystém MeSH
- lidé MeSH
- Schisandra * MeSH
- testy akutní toxicity MeSH
- voda MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- chemické látky znečišťující vodu * MeSH
- voda MeSH
Schisandra chinensis is a potential plant for production of nutrient supplements due to adaptogens content. The dominant bioactive substance, lignan schisandrin, has positive effects on human health, but it can cause possible allelopathic effects in relation to other plants. S. chinensis is not native to European ecosystems, and its ecotoxicological properties have not been verified yet. Lemna minor was selected as a model aquatic plant to test its potential impact on the aquatic environment. Crude water extract from S. chinensis fruits, simulating the natural soaking of active substances in a surface water body, was used in treatments from 0.045 to 45 mg/L (according to the content of schisandrin as the dominating lignan). During seven days of cultivation, the growth (number of plants, leaf area, fresh weight) and photosynthetic activity of L. minor fronds were assessed. In low treatments (0.045 and 0.09 mg/L), the extract of S. chinensis did not cause any changes in duckweed growth parameters or photosynthetic performance. Higher treatments (0.45 and 0.9 mg/L) caused significant limitations in plants' number, total leaf area, and fresh weight. The photosynthetic parameters (basal chlorophyll fluorescence, quantum yields) were affected only by 0.9 mg/L. The highest treatment, 45 mg/L, exhibited extreme toxicity to duckweed plants causing their death during the first five days of cultivation. Schisandrin and other bioactive substances extractable from S. chinensis fruits can negatively impact water biota in the case of massive contamination of surface water.
- Klíčová slova
- Adaptogen, Lemna minor, Lignan, Photosynthesis, Phytotoxicity, Schisandrin,
- MeSH
- chemické látky znečišťující vodu * toxicita MeSH
- ekosystém MeSH
- lidé MeSH
- lignany * toxicita analýza MeSH
- Schisandra * MeSH
- voda MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- chemické látky znečišťující vodu * MeSH
- lignany * MeSH
- schizandrin MeSH Prohlížeč
- voda MeSH
The production of graphene oxide (GO) along with its applications in various aquatic environments is vastly increasing thanks to its rapidly expanding range of new GO-based environmental technologies. Therefore, the fate of GO in aquatic environments is an important issue, as it could become an environmental challenge if its potential toxic mechanism is not addressed properly. Number of studies reporting the toxicity of GO to various aquatic organisms is still increasing. However, research data on the possible toxic mechanism of GO towards aquatic plants have yet to be collected, especially regarding GO's surface chemistry. Here, we studied the interaction of three differently oxidized GO systems with model aquatic plant Lemna minor. We found that although none of the three GOs caused lethal phytotoxicity to Lemna after 7 days, the mechanism of action was dependent on the GO's surface oxidation. Based on the amount of functional surface groups, the GO was able to directly interact with the Lemna's root through its edges. However, in this case in contrast to algae and crustaceans, the interaction did not lead to a mechanical damage. Therefore, our results showed that GO is not hazardous to Lemna minor even at very high concentrations (up to 25 mg/L), because the root barrier proved to be strong enough to prevent GO's penetration and its consequent toxicity.
- Klíčová slova
- Aquatic plants, Graphene oxide, Lemna minor, Mechanical injury, Phytotoxicity,
- MeSH
- Araceae * MeSH
- grafit * toxicita MeSH
- rostliny MeSH
- vodní organismy MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- grafit * MeSH
- graphene oxide MeSH Prohlížeč
Antibiotics in water and wastewater have been determined extensively. The treatment of antibiotics in water needs evaluation of possible harmful effects on aquatic ecosystems and human health. This paper presents the toxicity evaluation of antibiotics after their treatment with ferrate (VI) (FeVIO42-, Fe(VI)) in water. The antibiotics (sulfamethoxazole (SMX), erythromycin (ERY), ofloxacin (OFL), ciprofloxacin (CIP), tetracycline (TET), oxytetracycline (OXY), and trimethoprim (TMP)) were treated at pH 8.0 by applying two concentrations of Fe(VI) to have molar ratios of 5:1 and 10:1 ([Fe(VI)]:[antibiotic]). Under the studied conditions, incomplete removal of antibiotics was observed, suggesting that the treated solutions contained parent antibiotics and their transformation products. The toxicity of antibiotics without Fe(VI) treatment was tested against freshwater green alga Raphidocelis subcapitata and cyanobacterium Synechococcus elongatus, which were determined to be generally sensitive to antibiotics, with EC50 < 1.0 mg/L. The toxicity of Fe(VI) treated solution was tested against R. subcapitata. Results found no toxicity for the treated solutions of OFL, CIP, and OXY. However, SMX, ERY, and TET remained toxic after Fe(VI) treatment (i.e., more than 75% growth inhibition of R. subcapitata). Results demonstrated that R. subcapitata may be applied to test the toxicity of antibiotics after oxidative treatments.
- Klíčová slova
- Algae, Antibiotics, Cyanobacteria, Ecotoxicity, Ferrate, Oxidation,
- MeSH
- antibakteriální látky toxicita MeSH
- chemické látky znečišťující vodu * toxicita MeSH
- čištění vody * MeSH
- ekosystém MeSH
- lidé MeSH
- oxidace-redukce MeSH
- Synechococcus MeSH
- voda MeSH
- železo MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- antibakteriální látky MeSH
- chemické látky znečišťující vodu * MeSH
- ferrate ion MeSH Prohlížeč
- voda MeSH
- železo MeSH
Graphene oxide (GO) as the most studied hydrophilic graphene derivative can be deployed in a broad spectrum of environmental technologies opening the issue of its ecotoxicity. Nevertheless, the information about its behavior in complex aquatic environment is still not sufficient. Here, we studied the interaction of three differently oxidized GO systems with planktonic and benthic crustaceans. By standard toxicity tests, we observed the importance of feeding strategy as well as the surface oxidation of GO with respect to GO's ecotoxicity. However, to gain a clearer insight into GO's environmental fate, we introduced a pre-treatment with algae as the most common source of food for crustaceans. Such an adjustment mimicking the conditions in real aquatic ecosystems resulted in complete mitigation of acute toxicity of GOs to all organisms and, more importantly, to the eradication of oxidative stress caused by GOs. We argue, that the pre-exposition of food is a crucial factor in GO's overall environmental fate, even though this fact has been completely neglected in recent studies. These experiments proved that GO is not a hazardous material in complex aquatic environments because its acute toxicity can be successfully mitigated through the interaction with algae even at very high concentrations (25 mg/L).
- Klíčová slova
- Algae, Aquatic crustaceans, Aquatic environment, Graphene oxide, Toxicity mitigation,
- MeSH
- chemické látky znečišťující vodu * toxicita MeSH
- ekosystém MeSH
- grafit * toxicita MeSH
- plankton MeSH
- testy toxicity MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- chemické látky znečišťující vodu * MeSH
- grafit * MeSH
- graphene oxide MeSH Prohlížeč
In recent years, antibiotics have been used for human and animal disease treatment, growth promotion, and prophylaxis, and their consumption is rising worldwide. Antibiotics are often not fully metabolized by the body and are released into the aquatic environment, where they may have negative effects on the non-target species. This review examines the recent researches on eight representative antibiotics (erythromycin, trimethoprim, sulfamethoxazole, tetracycline, oxytetracycline, ofloxacin, ciprofloxacin, and amoxicillin). A detailed overview of their concentrations in surface waters, groundwater, and effluents is provided, supported by recent global human consumption and veterinary use data. Furthermore, we review the ecotoxicity of these antibiotics towards different groups of organisms, and assessment of the environmental risks to aquatic organisms. This review discusses and compares the suitability of currently used ecotoxicological bioassays, and identifies the knowledge gaps and future challenges. The risk data indicate that selected antibiotics may pose a threat to aquatic environments. Cyanobacteria were the most sensitive organisms when using standard ecotoxicological bioassays. Further studies on their chronic effects to aquatic organisms and the toxicity of antibiotic mixtures are necessary to fully understand the hazards these antibiotics present.
- Klíčová slova
- Antibiotic, Ecotoxicity, Environmental concentration, Human consumption, Veterinary use,
- MeSH
- amoxicilin MeSH
- antibakteriální látky analýza toxicita MeSH
- chemické látky znečišťující vodu analýza toxicita MeSH
- ciprofloxacin MeSH
- ekotoxikologie MeSH
- erythromycin MeSH
- hodnocení rizik MeSH
- monitorování životního prostředí * MeSH
- podzemní voda MeSH
- sulfamethoxazol MeSH
- tetracyklin MeSH
- trimethoprim analýza MeSH
- vodní organismy MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- amoxicilin MeSH
- antibakteriální látky MeSH
- chemické látky znečišťující vodu MeSH
- ciprofloxacin MeSH
- erythromycin MeSH
- sulfamethoxazol MeSH
- tetracyklin MeSH
- trimethoprim MeSH
Development of anti-fouling surfaces is a major challenge in materials research. Microorganisms growing as biofilms have enhanced tolerance to antimicrobial strategies including antibiotics and antiseptics complicating the design of anti-fouling surfaces. Silver nanoparticles (AgNPs) are a promising antimicrobial technology with broad spectrum efficacy with a reduced likelihood of microorganisms developing resistance to the technology. This study tested the efficacy of new immobilized AgNP-modified surface technology against three common opportunistic pathogens grown either as monocultures or as cocultures. The presented study fills a gap in the literature by quantifying the efficacy of immobilized AgNP particles against multispecies biofilms. Polyethylene (PE) surfaces functionalized with the AgNPs were highly effective against Pseudomonas aeruginosa biofilms reducing viable cell counts by 99.8 % as compared to controls. However, the efficacy of the AgNP-modified PE surface was compromised when P. aeruginosa was cocultured with Candida albicans. Interspecies interactions can strongly influence the efficacy of anti-fouling AgNP coatings highlighting the need to test surfaces not only against biofilm phenotypes but under conditions representative of applications including the presence of multispecies consortia.
- Klíčová slova
- Antimicrobial surfaces, Biofilm, Inhibition of microbial surface colonization, Silver nanoparticles, Surface functionalization,
- Publikační typ
- časopisecké články MeSH
