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With the growing requirements on environmental protection in drilling fluid additives, the traditional anti-collapsing agents are unable to meet the demand. Therefore, improving the environmental protection performance of anti-collapse agents has drawn great attention from scientists. Organic amines are commonly used as anti-collapse agents due to their good anti-collapse properties. In this paper, alkali diamines have been selected as research objects to evaluated the anti-collapse abilities by immersion tests and linear expansion experiments. The experimental results showed that alkyl diamines demonstrate good anti-collapse abilities. However, with increase in the number of C atoms, the solubility of alkyl diamines decreases, and the inhibition by the potassium dichromate method, dilution and inoculation method, and luminescent bacteria method. The result show that the biodegradability of the alkyl diamine anti-collapse agents increase gradually increase in the number of carbon atoms in the chain, while the solubility and biotoxicity decrease. Therefore, the longer the alkyl diamine carbon chain length, the better the environmental performance of anti-collapse agents. Hence, this research provides a guideline for synthesizing new organic amine anti-collapse agents.

Organic ligands are commonly believed to decrease the toxicity of metal ions, but there is few experimental evidence, especially for chromium (Cr(III)), which often coexists with organic compounds in industrial effluents. Here, the complexation of Cr(III) with acetate, lactate, l-tartrate, biphthalate and oxalate was tested under the conditions of a toxicity test, with high ion strength, by spectroscopic techniques. The stability constants of the complexes were found to follow the order Cr(III) oxalate > Cr(III) lactate > Cr(III) biphthalate > Cr(III) L-tartrate > Cr(III) acetate. Then, aquatic toxicity of Cr(III) to Photobacterium phosphoreum for a 15-min exposure period was tested in the absence and presence of organic ligands. Results unexpectedly show that the complexation of Cr(III) with acetic, lactate, l-tartrate and biphthalate resulted in enhanced toxicity to luminescent bacteria, whereas the coordination of Cr(III) with oxalate sharply alleviated the toxicity of individual oxalate and inorganic Cr(III), which was further confirmed by the scanning electron microscopy (SEM). Our findings show thus that organics do not always mitigate the toxicity of Cr(III) in acidic water.

This study investigated the degradation of benzophenone-4 (BP-4) in a UV/chlorine disinfection process, with chlorination and UV disinfection as comparisons. With a degradation efficiency of 80% after 10 s, the UV/chlorine process significantly enhanced the degradation of BP-4. However, a rebound of 36% of the initial concentration was observed in the UV/chlorine process ([free active chlorine (FAC)]0:[BP-4]0 = 1:1, pH = 7). The same tendency appeared under the addition of alkalinity, Cl−, and humic acid (HA). This work interpreted this interesting kinetic tendency from the perspective of mechanism. In fact, the transformation between the chlorinated product P1 and BP-4 was reversible under certain conditions. The inhomogeneous charge distribution of the C Cl bond in P1 led to the photolytic dechlorination of P1. This transformation caused an increase in BP-4 concentration. In addition, the increase in the UV light power promoted the photodecomposition of P1 under the experimental condition. In addition, this study evaluated the change in absorbable organic halogens (AOX) and three kinds of toxicity changes in the BP-4 solution after chlorination and the UV/chlorine process, including the acute toxicity of luminescent bacteria, endocrine disrupting effect and cytotoxicity. The UV/chlorine process exhibited lower ecotoxicity than chlorination in water treatment.

Previous studies demonstrated long-term stimulation of some commercial personal care products (PCPs) on freshwater luminescent bacteria Vibrio qinghaiensis sp .-Q67 (Q67). However, whether a certain component can affect mixture's hormetic effect is still unknown. In this paper, two of ingredients in PCPs, 2-phenoxyethanol (PhE) and polyethylene glycol 400 (PEG400), were selected as object compounds to explore the relationship between concentration-response (CR) of mixtures and that of a single component. It was found that PEG400 has monotonic CR (MCR) on Q67 both at the short-term (0.25 h) and long-term (12 h) exposures while PhE has MCR at 0.25 h and hormetic CR (HCR) at 12 h. Here, the concentration-response curves (CRCs) of PEG400 at 0.25 and 12 h are overlapped each other and the CRCs of PEG400 are on the right of PhE. If the pEC 50 is taken as a toxic index, the toxicities of PEG400 at two times are basically the same, and those of PhE are the same, too, but PhE is twice as toxic as PEG400. For the mixtures of PEG400 and PhE, all rays except R1 have MCRs at 0.25 h while all rays have HCRs at 12 h where the higher the mixture ratio of PhE is, the more negative the maximum stimulation effect is. More importantly, the E min values of all rays are more negative (1.79–3.17-fold) than that of PhE worked alone, which implies that the introduction of PEG400 significantly enhances stimulative effect of PhE. At 0.25 h, all binary mixture rays but R1 produce a low-concentration additive action and high-concentration synergism. At 12 h, all rays display additive action, antagonism, additive action, and synergism in turn when the concentration changes from low to high. The overall findings suggested toxicological interactions should be considered in the risk assessment of PCPs and their potential impacts on ecological balances.

Diclofenac was frequently found in various waters, indicating conventional wastewater treatment methods ineffective in its removal. In this study, LaFeO3 (LFO) was synthesized and its catalytic activity of LFO as the activator of different oxidants such as persulfate (PS), hydrogen peroxide and peroxylmonosulfate (PMS) was evaluated in terms of DCF degradation. The influence of calcination temperature was examined on the catalytic activity of LFO. The effects of various parameters including pH levels, PMS concentration, LFO dose and initial DCF concentration were investigated on DCF degradation rate. The marginal effects of PMS concentration and LFO dose were compared. Langmuir-Hinshelwood (LH) model was used to quantitatively describe DCF degradation reaction in LFO/PMS system. The two constants, k (Limiting reaction rate at maximum coverage) and K (Equilibrium adsorption constant), were determined on the basis of LH model. The performance of LFO/PMS process was also estimated in the presence of various inorganic anions. The potential toxicity of LFO and PMS were evaluated using phytoplankton and the toxicity evolution during DCF degradation was also investigated using luminescent bacteria. This contribution provides a basic study regarding the potential application of heterogeneous PMS activation by perovskite LFO for both DCF removal and toxicity elimination.

Fifteen native luminescent bacteria were isolated from the Gulf of Thailand, and their sensitivity for the detection of toxicity of crude oil and its aromatic components was investigated. Of these isolates, Vibrio campbellii strain FS5 was one of the two most highly inhibited bacteria at all crude oil concentrations. This bacterium showed a decrease in luminescence intensity of between 10.7 and 80.2% after a 15-min exposure to 0.0001–10 mg/L of crude oil. The degree of bioluminescence inhibition increased with increasing concentrations of crude oil. The presence of crude oil at all concentrations had negative effects on the log bioluminescence per log number of viable cells after 15- to 105-min exposure. About 10 to 100 times, lower half maximal effective concentration (EC50) values were observed for polycyclic aromatic hydrocarbons (PAHs) than those for benzene, toluene, ethylbenzene, and xylene (BTEX). In the presence of each individual BTEX and PAH, the bioluminescence inhibition increased with increasing exposure time (1–32 h). This indigenous bacterium can be used as a simple and general indicator of oil contamination and its impact on coastal waters as well as for assessing potential toxicity during oil bioremediation.

Trans-resveratrol becomes more and more popular all over the world as a powerful antioxidant. Since its positive properties, including antioxidant, anti-inflammatory, anti-tumor are indisputable, nowadays trans-resveratrol is used as a component of various products from nutriceutics to body care formulations, where it is supposed to behave as natural antioxidant and anti-aging compound. It is also added to food packaging materials to increase their stability or/and prevent oxidation. Nevertheless, being released to the environment resveratrol easily forms various transformation products with potentially negative environmental and health effects. The present paper deals with transformation of pure resveratrol and its formulation used as UV-protectors in conditions of aquatic chlorination. Over 80 transformation products were tentatively identified using gas chromatography-high resolution mass spectrometry (GC-HRMS) and ultra pressure liquid chromatography-high resolution mass spectrometry (UPLC-HRMS). Chlorinated phenols and biphenyls are the most relevant among them. Estimation of toxicity of resveratrol products was carried out using luminescent bacteria V. fischeri tests.

Doxazosin (DOX), a selective alpha blocker, is widely used in medical therapy as an effective antihypertensive agent. It is a frequently prescribed drug and for this reason, environmental and ecotoxicological research is of great importance in terms of exposure and risk for both aquatic species and humans. In this study we focused on photolytic and TiO2 photocatalytic degradation processes of doxazosin under different simulated conditions, with the emphasis on identification of degradation products. Photolytic (without TiO2) experiments were performed in the presence and absence of oxygen, while photocatalytic degradation of doxazosin aqueous solution has been carried out under constant oxygen flow. DOX degradation was more efficient in the TiO2/UVA photocatalytic experiment than during photolytic processes (UVA and UVC, UVC-N2). LC-HRMS analyses with electrospray ionization allowed observing the formation of several major degradation products depending on the reaction conditions (presence or absence of oxygen, photocatalysis). The transformation products were identified based on exact mass measurements, isotopic distribution, and fragmentation pattern. Among them, dominated C17H21N5O3 and C17H23N5O4 (cleavage of the dioxane cycle), and C23H25N5O7 (hydroxylation). The detailed degradation pathway has been proposed. Toxicity testing with V. fischeri luminescent bacteria revealed higher toxicity of samples in photolytic rather than photocatalytic experiments which might be attributed to the formation of different products.

In this study, a biosensor is designed to remove mercury as a toxic metal contaminant from the soil. The rhamnolipid biosurfactant was used to extract the mercury sorbed to soil to the aqueous phase. An immobilized bioluminescent bacterium (Escherichia coli MC106) with pmerRBPmerlux plasmid is assisted for mercury detection. A significant decrease in luminescence level was observed in a biosensor system containing contaminated soil sample extract. The concentrations of extracting mercury are well correlated with the mercury toxicity data obtained from experimental biosensor systems according to the RBL value. The optimum aeration rate of 20 ml/min was obtained for the biosensor systems. The advantage of such a biosensor is the in situ quantification of mercury as a heavy metal contaminant in soils. Therefore, this system could be proposed as a good biosensor-based alternative for future detection of heavy toxic metals in soils.

The production of biodegradable plastics is considered to be a way to reduce plastic waste issue. Among others, oxo-degradant additives enable a faster degradation of plastics in the environment. However, the introduction of these new materials could provoke the release of substances potentially toxic in the environment. This work determined and compared the toxicity of leachates from various additivated polymers (polyethylene, PE; polypropylene, PP; polystyrene, PS) upon different test organisms: plants (Sorghum saccharatum, Lepidium sativum, Sinapis alba, and Vicia faba), crustacean (Daphnia magna), and luminescent bacteria (Vibrio fischeri). Daphnia magna survival was mainly affected by PS and PP leachates (72% and 61% effect, respectively) while PS notably reduced the reproduction rate. On plants, only PP exerted a negative effect (S. saccharatum IG% 32.4), while V. fischeri always showed values around 50%. The data integration, through the Toxicity Test Battery Integrated Index (TBI) approach, allowed to rank the leachates toxicity as PE > PS > PP. This result could be mainly ascribable to the highest metals content in PE since no difference with organic compounds analysis was evidenced. In conclusion, since the polymers exerted dissimilar toxicity, the additive could not be considered the sole responsible of the measured toxicity, but its role in the enhancement of the virgin polymers leachates effects can be solidly hypothesized.

Fish carpaccio is a ready-to-eat product with a very limited shelf life. In the present work, the use of high pressure treatment (HP) and/or antimicrobial edible film was studied in order to improve quality and stability of salmon carpaccio. In a preliminary part of the work, a film composed of gelatin plus chitosan incorporating clove essential oil was selected, based on its physicochemical and antimicrobial properties. Eugenol and β-caryophyllene, the main volatile components of the film, migrated to salmon muscle, the release being favored by HP and storage time. Concurrently, reducing power of the muscle increased, resulting in prevention of lipid oxidation derived from either HP or refrigerated storage. HP treatment reduced total microbial counts by 1.5 log cycles from the onset of storage, whereas the film reduced it by 2 log cycles after 3 days. The combination of HP and edible film exerted the most intense antimicrobial effect, total bacterial counts, luminescent bacteria, HS-producing organisms, pseudomonads, enterobacteria, and lactic acid bacteria remaining constant or under detection limit over the whole storage period (11 days). The combined use of HP treatment and gelatin–chitosan–clove essential oil film is an effective way of improving quality and stability of salmon carpaccio., This research was financed by the Spanish Ministry of Economy and Competitiveness (projects I3-200670l141, AGL2014-52825-R). Author López de Lacey was funded by the JAE-CSIC predoc program and Gómez-Estaca by the “Juan de la Cierva” program.

It has been stated by researchers that the antibiotic polymyxin B sulfate (POL) is a key component inducing time-dependent antagonism in freshwater luminescent bacteria, Vibrio qinghaiensis sp.-Q67, exposed in the ternary mixture system of the ionic liquids, pesticide and antibiotics. However, the previous statement is limited to ternary and quaternary mixtures without considering situations such as the binary system. In order to prove the direct inducing of antagonism by POL in a more complete and systematic way, two categories of experiments (adding POL in non-antagonistic ternary system and decomposing antagonistic ternary system with POL into the binary system) have been conducted in this paper. The results showed that quaternary mixture systems (adding POL to non-antagonism ternary mixture, up verification) exhibit antagonistic action in a majority of rays, at some point in the experiment. However, by decomposing the antagonistic ternary mixtures with POL into binary mixtures (down verification), the combined toxicities of binary mixtures at all time points in the experiment are additive. Obviously, the POL has a significant contribution to antagonism only in the ternary and quaternary mixtures, but not in the binary mixtures. We can draw a new conclusion that the antagonism of the multi-component mixtures is induced by at least three components (including POL), with complex chemical interactions. Therefore, considering POL's influence of antagonism as an example, future environmental protection practitioners and academic researchers should construct more scenarios of mixtures when assessing the influences and reactions of certain chemicals causing pollutions.

Although magnetic ionic liquids (MILs) are not yet industrially applied, their continued development and eventual commercial use may lead to their appearance into the aquatic ecosystem through accidental spills or effluents, consequently promoting aquatic contaminations. Furthermore, the deficient information and uncertainty surrounding the environmental impact of MILs could be a major barrier to their widespread industrial application and international registration. Thus, in the present work, a range of cholinium salt derivatives with magnetic properties was synthesized and their ecotoxicity was evaluated towards the luminescent bacteria Vibrio fischeri. The results suggest that all MILs structures tested are moderately toxic, or even toxic, to the bacteria. Furthermore, their toxicity is highly dependent on the structural modifications of the cation, namely the alkyl side chain length and the number of hydroxyethyl groups, as well as the atomic number of the metal anion. Finally, from the magnetic anions evaluated, the [MnCl4]2- is the less toxic. In order to improve the knowledge for the prospective design of environmentally safer MILs, it is important to expand this study to other aquatic organisms at different trophic levels. published

Chlorination is essential to the safety of reclaimed water; however, this process leads to concern regarding the formation of disinfection byproducts (DBPs) and toxicity. This study reviewed the formation and control strategies for DBPs and toxicity in reclaimed water during chlorination. Both regulated and emerging DBPs have been frequently detected in reclaimed water during chlorination at a higher level than those in drinking water, indicating they pose a greater risk to humans. Luminescent bacteria and Daphnia magna acute toxicity, anti-estrogenic activity and cytotoxicity generally increased after chlorination because of the formation of DBPs. Genotoxicity by umu-test and estrogenic activity were decreased after chlorination because of destruction of toxic chemicals. During chlorination, water quality significantly impacted changes in toxicity. Ammonium tended to attenuate toxicity changes by reacting with chlorine to form chloramine, while bromide tended to aggravate toxicity changes by forming hypobromous acid. During pretreatment by ozonation and coagulation, disinfection byproduct formation potential (DBPFP) and toxicity formation potential (TFP) occasionally increase, which is accompanied by DOC removal; thus, the decrease of DOC was limited to indicate the decrease of DBPFP and TFP. It is more important to eliminate the key fraction of precursors such as hydrophobic acid and hydrophilic neutrals. During chlorination, toxicities can increase with the increasing chlorine dose and contact time. To control the excessive toxicity formation, a relatively low chlorine dose and short contact time were required. Quenching chlorine residual with reductive reagents also effectively abated the formation of toxic compounds.

Phthalates has been widely used in children's toys as plastic plasticizers and softeners. The aim of this study was to extract chemically phthalates from 20 toy samples and determine toxicity using the Vibrio fischeri luminescent bacteria test. Subsequently the (the concentration producing 50% of maximal effect) was employed to characterize the toxicity of the sample and select the appropriate solvent from methanol, ethanol or glycerol in order to assess the adverse effects of di-n-butyl phthalate (DBP) or di-2-ethylhexyl phthalate (DEHP) and not solvent interference on Vibrio fischeri. Data showed that toxicity of glycerol was relatively low when the concentration was less than 0.44 mol/L. Therefore glycerol was selected as solvent. DBP and DEHP produced toxicity on Vibrio fischeri in the order of DEHP > DBP. The was 0.437 and 0.182 mol/L, respectively. This study provides the foundation for examination of combined toxic effects of the mixture of DBP and DEHP on Vibrio fischeri which is of signif...

Tungsten(VI) oxide, WO3, was studied and used as a heterogeneous catalyst for the liquid-phase oxidative abatement and solid-phase decontamination of simulants of chemical warfare agents, CWAs. The catalytic performance of WO3 was compared to the one of a soluble W-containing model catalyst, W(IV)-heptaisobutyl polyhedral oligomeric silsesquioxane, W-POSS. In liquid-phase abatement tests, WO3 promoted a complete degradation of the toxic agent simulant within 24 h, in the presence of aqueous hydrogen peroxide, at room temperature. In solid-phase decontamination tests, when WO3 was mixed with sodium perborate as a solid oxidant, it was also tested in the decontamination of a cotton textile support from organosulfide and organophosphonate agents (simulants of blistering and nerve CWAs, respectively), showing promising performances comparable to, or sometimes better than, a nanostructured TiO2 catalyst, taken as a reference material. The environmental impact of the WO3 catalyst was assessed on bioluminescent Photobacterium leiognathi Sh1 bacteria, over which no acute nor chronic detrimental effects were recorded. Then, when in contact with a vegetable species such as Phaseolus vulgaris L. (common bean), WO3 did not cause damage to the photosynthetic apparatus of the plant, whereas a clear inhibition of the seed germination was evidenced.

A biosensitive element in the form of bacterial Photobacterium phosphoreum cells immobilized in poly(vinyl alcohol) cryogel was tested for the determination of different mycotoxins under discrete and flow-through analysis conditions. The immobilized bioluminescent cells made it possible to quantify the presence of Ochratoxin A, Sterigmatocystin, Zearalenone, and Deoxynivalenon in aqueous media in a wide range of their concentrations (0.017&ndash, 56 mg/L, 0.010&ndash, 33 mg/L, 0.009&ndash, 14 mg/L, and 0.026&ndash, 177 mg/L, respectively) via measuring the quenching of cell luminescence. The flow conditions allowed the analysis sensitivity to be improved by an order of magnitude in terms of detected concentrations. Using the immobilized luminescent bacterial cells, we have shown the possibility of evaluating the efficiency of the mycotoxins&rsquo, hydrolysis under the action of enzymes. In this way, a 94 &plusmn, 4.5% efficiency of Zearalenone hydrolysis with hexahistidine-containing organophosphorus hydrolase for 1h-long treatment of the mycotoxin solution (100 mg/L) was shown.

This study presented a HPTLC platformed luminescent biosensor system for screening captan residue. First, the potential bio-effects of layers materials on the detectability of a luminescent bacteria Photobacterium phosphoreum (ATCC 11040) as the sensor cell were assessed. From comparison, it was noteworthy that the combination of sensor cells with normal silica gel layer exclusively gave outstanding detectability (10 ng/zone). On this basis, HPTLC mediated separation and biosensing was further optimized. Then, the obtained graphic results were digitally quantified via software processing, offering satisfactory selectivity, linearity (R

The removal of acetaminophen (AAP) in aqueous solution by the UV/chlorine process was evaluated. The effect of chlorine dose, the initial AAP concentration, pH value, and UV intensity on the reaction were also investigated. The degradation mechanism and the ecological risk were further discussed. The results indicated that AAP degradation fitted pseudo-first-order kinetics. Compared with UV alone or dark chlorination, the combination of UV and chlorine significantly accelerated the degradation process. The AAP degradation was positively affected by chlorine dose and UV intensity, while negatively affected by the initial AAP concentration and ammonia nitrogen concentration during the UV/chlorine process. The frontier orbital theory analysis shows that the C5 position in the benzene ring of AAP is likely to be the first site attacked by HO• and Cl• radical to form the products. Twelve intermediates were identified by Q-TOF and GC-MS. The possible degradation pathways were also proposed. Luminescent bacteria experiment and ECOSAR prediction both revealed that acute toxicity of AAP degradation could only be partially reduced. Ecological risks during the UV/chlorine process need to be further evaluated.

Predicting the crucial effect of single metal pollutants against the aquatic ecosystem has been highly debatable for decades. However, dealing with complex metal mixtures management in toxicological studies creates a challenge, as heavy metals may evoke greater toxicity on interactions with other constituents rather than individually low acting concentrations. Moreover, the toxicity mechanisms are different between short term and long term exposure of the metal toxicant. In this study, acute and chronic toxicity based on luminescence inhibition assay using newly isolated Photobacterium sp.NAA-MIE as the indicator are presented. Photobacterium sp.NAA-MIE was exposed to the mixture at a predetermined ratio of 1:1. TU (Toxicity Unit) and MTI (Mixture Toxic Index) approach presented the mixture toxicity of Hg2+ + Ag+, Hg2+ + Cu2+, Ag+ + Cu2+, Hg2+ + Ag+ + Cu2+, and Cd2+ + Cu2+ showed antagonistic effect over acute and chronic test. Binary mixture of Cu2+ + Zn2+ was observed to show additive effect at acute test and antagonistic effect at chronic test while mixture of Ni2+ + Zn2+ showing antagonistic effect during acute test and synergistic effect during chronic test. Thus, the strain is suitable and their use as bioassay to predict the risk assessment of heavy metal under acute toxicity without abandoning the advantage of chronic toxicity extrapolation.

Photocatalytic degradation of typical pharmaceuticals in natural sunlight and in actual water is of great significance. In this study, the oxygen or nitrogen linked heptazine-base polymer (ONLH) was successfully incorporated with TiO2 nanoparticles and formed a TiO2/ONLH nanocomposite which was responded to the natural sunlight. Under natural sunlight, the TiO2/ONLH can effectively degrade ten types of pharmaceuticals. In particular, fluoroquinolone containing N-piperazinyl, and cardiovascular drugs containing long aromatic side chains were easily degraded. The half-life of the best degradation performance of propranolol was less than 5 min. The rate constants of propranolol using the TiO2/ONLH were approximately six- and eight-fold higher than those of pristine TiO2 and ONLH, respectively. Two reactive species (OH and O2-) facilitated the rapid degradation of propranolol, which occurred primarily through the hydroxyl radical addition, ring-opening, and ipso substitution reactions. An acute toxicity test using luminescent bacteria indicated that the toxicity of the propranolol reaction solution gradually decreased with lower total organic carbon (TOC). According to the toxicity evaluation of monomer products, the TiO2/ONLH also reduced the generation of toxic transformation products. The effects of actual water/wastewater have further shown the TiO2/ONLH might be applied for the removal of pharmaceuticals in wastewater.

Today, nanomaterials have significant potential for practical application in a variety of research areas, in industrial production, the agrarian sector and in everyday life. Nanomaterials have received considerable attention due to the complex of their special properties, including taking into account the large specific surface area and high biological activity [1, р. 97-114; 2 р. 5728-5743]. In connection with the rapid development of nanotechnologies, nanomaterials of various shapes and diameters were obtained, which were then used in the production of products and products [3, р. 2064-2110; 4, р. 1504-1534]. On the one hand, skilled application of nanoparticles opens up new opportunities in many areas of human activity, and on the other hand due to its small size and the ability to penetrate through tissues can cause toxic effects in relation to living organisms. Therefore, scientific research must be aimed at studying the influence of nanomaterials on biological objects of different levels of organization, in particular on the analysis of the state of subcellular, cellular, organ levels and the whole organism [5, p. 51-56]. The aim was to investigate the effect of nanocomposites and their component nanosized SiO 2 on different types of microorganisms. Materials and methods. Influence of nanomaterials was studied using beer yeast, bioluminescent bacteria and associative culture of aerobic bacteria. Nanomaterials were provided by the Research Institute of Molecular Technologies in Milan, Italy. An associative culture was used ( Pseudomonas pseudo alcaligenes 102 , Bacillus subtilis 138 , Stenotrophomonas maltophilia 5246 UKM) from the collection of the Institute of Microbiology and Virology. D.K. Zabolotnoy National Academy of Sciences of Ukraine. The associative culture in the ratio 1: 1: 1 was cultivated on a nutrient medium (Himedia, India) during the day. After incubation, the suspension was applied to an agarified nutrient medium. In the center of the Petri dish, with a lawn crop, the agar blocks (hungry 4% agar with concentrations of nanomaterials) were sterilized. The culture was incubated for 2 days at a temperature of 28 0 C and the analysis was performed taking into account the fact and size of the growth retardation of the colonies (mm) [6, р. 273]. The biological effects of the NPs and NC were studied in form colloidal water mixtures obtained in appropriate volumes of 3% of sodium chloride. Three strains of luminescent bacteria ( V. fischeri F1, P. leiognathi Sh1) from collection of Crimean State Medical University (Simferopol, Ukraine) To determine the acute (toxicity) of samples, in blisters of a luminometer BLM 8801, a mixture of 0.8-0.9 ml of the test solution in a 2.5-3% solution of NaCl, 100 μl of a buffer solution with pH = 7.0 (phosphate) and 50 μl of bacterial suspension. The change in the intensity of the bioluminescence was recorded for 30-120 minutes using a recorder (LKB Bromma, Sweden). The analyzes were carried out at a temperature of 28-30 ° C. The biological effect of the samples was evaluated qualitatively by the nature of the graphic dependences of the intensity of the bioluminescence on the sample concentration. The presence of pronounced concentration inhibition of bioluminescence, reduction of bioluminescence to 50% and lower were treated as toxic [7, р. 93-97]. To study the influence of nanomaterials on beer yeast, they took a pure culture of Saccaromyces cerevisiae strain U-517 from the collection of the Institute of Microbiology and Virology. D.K. Zabolotny. Cultivated on a medium of YPD (yeast extract - 1%, peptone - 2%, glucose / dextrose - 2%, agar - 2.5%) during the day at 28 0 C. The daily subplanted culture at a concentration of 105 cells / ml in 25 ml of YPD medium with certain concentrations of nanomaterials: 150 mg / L, 300 mg / L, 450 mg / L, 600 mg / l and incubated for 1 day. Cultivate the day statically in falcons of 50 ml. The number of cells was calculated by the method of counting in the camera Goryaevа. Cell counting occurred in a heterogeneous population of Saccaromyces cerevisiae in a stationary phase of growth. MTT test was performed as follows. After daily processing with nanomaterials, 100 μl of yeast culture was incubated in the presence of 20 μl of 5 mg / ml MTT for 3.5 hours at 37 ° C in a 96-well plate in three replicates. After incubation, the culture medium was removed and the formazan crystals were dissolved in 150 μl DMSO. Incubated in the presence of DMSO in dark 15 minutes and measured the performance of the optical density (CO) formazan at a wavelength of 620 nm with a Multiskan FC device with version 1.00.94 and serial number 357-902509 [8, р. 383-393]. Research results. Having studied the influence of nanomaterials on the associative culture of aerobic bacteria, no toxic effects were found. The results of the experiment indicate the absence of antibacterial action of newly synthesized nanocomposites based on saponites on aerobic soil bacteria. For the action of nanosized SiO 2 material at a concentration of 600 mg / l around the agar block, there was no significant growth retardation of the colonies of aerobic bacteria. Thus it can be argued that the antibacterial activity of this material is weak in the associative culture of soil bacteria at a concentration of 600 mg / l. In the study of the acute effects of nanomaterials on bioluminescent bacteria, in 10 and 30 minutes, the newly synthesized nanocosities did not exhibit inhibitory activity, depending on the time and concentrations. The study of acute toxicity of samples showed that SiO 2 nanomaterial suppressed bacterial bioluminescence. During the 10-minute incubation of bacteria in solutions of nanomaterials 150 mg / l, 300 mg / l, 450 mg / l and 600 mg / l, the intensity of the luminescence of bacteria decreased by 18.5%, 54.5%, 61.5% and 59 , 5% respectively. During the 30-minute incubation, the light concentrations decreased by 20.61%, 56.2%, 61.3%, 62.5%, respectively. Accordingly, one can conclude that the inhibitory effect of the nanomaterial depends on the concentrations, and by increasing the incubation time, the change in the inhibitory effect was not significant. Accordingly, the curvature of the bioluminescence of bacteria V. Fischeri , similarly to the previous results, was not detected in the bacteria Р. leiognathi , the inhibitory effect of nanocomposites on the basis of saponites. The nanosized SiO 2 material reduced the intensity of the glow of bacteria. Thus, with a 10-minute incubation in solutions of nanomaterials of 150 mg / l, 300 mg / l, 450 mg / l and 600 mg / l, the intensity of bioluminescence decreased by 13.3%, 35.2%, 41.4% and 42.3%. During incubation for 30 minutes the indices did not change significantly. Having studied the influence of nanomaterials on bacteria, the next step was to investigate the effect of nanomaterials on the growth of yeast cells. It has been established that under the influence of saponite-based nb-containing nanocomposites, the number of S. cerevisiae cells is significantly increased. The nanosized SiO 2 material in the range of 450-600 mg / L showed an inhibitory effect, the number of cells in the samples at concentrations of 450 mg / l and 600 mg / l was 1.96 ∙ 10 8 cells / ml and 1.87 ∙ 10 8 cells / ml, respectively , whereas in the control the given index was 2.06 ∙ 10 8 кл / ml. S. cerevisiae cells are susceptible to the effect of nanomaterials on them. To confirm the preliminary results and obtain more detailed information on the influence of nanomaterials on the intensity of biochemical processes in cells, an MTT test was performed. According to the MTT test, the most pronounced effect compared with the control was found for nanocomposites Nb-Saponite (Cl) and Nb-Saponite (Et) at concentrations of 300-600 mg / l. On average, for optical nanocomposites, the optical density was 0.547 y.o. and 0.645 y.o., while in control it was 0.32 y.o. As in previous experiments on counting the number of cells, we obtain the reproducibility of the results in determining the cytotoxicity of niobium-containing nanocomposites. The growth of optical density speaks of the properties of nanocomposites, in relation to the activation of biochemical processes in cells of S. cerevisiae . Nanomaterial SiO 2 did not exhibit cytotoxic action against S. cerevisiae cells. An insignificant decrease in this indicator for the effects of SiO 2 was observed at concentrations of 450 mg / l and 600 mg / l, it decreased by 9.37% and 12.5% respectively, compared with the control. Conclusion. The influence of Nb-containing nanocomposites based on saponites and their component - nanosized SiO 2 is studied in this work. It was noted that nanocomposites did not exhibit a toxic effect in the concentration range of 150-600 mg / l in relation to bioluminescent, aerobic bacteria and S. cerevisiae . For the action of nanosized SiO 2 , an inhibitory effect was observed to the listed microorganisms. Such results can be justified by the fact that the nanosize SiO 2 material caused inhibition of the parameters, since it is about 20 nm in size so the nanomaterial can penetrate the cell wall of microorganisms and cause a negative effect. In composite materials, SiO 2 during synthesis was agglomerated into large structures, ranging in size from 40-100 nm, thus losing its toxic properties. Keywords: nanomaterials, microorganisms, bacteria, brewer's yeast, nanocomposites

The antipsychotic drug quetiapine (QUT) has been frequently detected in sewage treatment plants. However, information on the fate of QUT in aquatic environments and its behavior during UV treatment is limited. In this study, QUT is shown not to be readily biodegradable in the Closed Bottle Test and the Manometric Respirometry Test according to OECD guidelines. The main biotransformation product (BTP) formed in the tests, a carboxylic acid derivative, was identified by means of high-resolution mass spectrometry. This BTP is presumably a human metabolite and showed higher detection rates than QUT in a river sampling campaign conducted in northern Germany. UV elimination kinetics of QUT at different initial concentrations (226.5, 45.3, 11.3, and 2.3 μmol L −1 ) were faster at lower initial concentrations. All seven phototransformation products (PTPs) could be still identified at initial concentration of 11.3 μmol L −1 . The photolytic mixture generated after 128 min of photolysis of QUT was not better biodegradable than QUT. Initial UV treatment of QUT led to the formation of several additional BTPs. Four of them were identified. The bacterial cytotoxicity and genotoxicity before and after phototransformation of QUT in a modified luminescent bacteria test (LBT) and the umu-test (ISO/FDIS 13829) showed cytotoxic effects in the LBT for QUT. Furthermore, PTPs had similar cytotoxic effects on luminescent bacteria. The umu-test did not reveal any genotoxic activity for QUT or PTPs. In conclusion, the release of QUT into sewage treatment plants and aquatic environments could result in the formation of a main BTP. Additional UV treatment of QUT would lead to the formation of additional BTPs. Moreover, treatment did not result in lower toxicity to tested organisms. In conclusion, UV treatment of QUT should be considered critically as a potential treatment for QUT in aquatic systems.

The wastewater generated in pharmaceutical process generally contains residual organic solvents (ROSs) which will cause the toxicity and inhibition of the micro-organisms in treating wastewater, thus affecting the treatment effect of wastewater. The aim of this study was to establish a system for the analysis and evaluation of microtoxicity and biodegradability of ROSs in pharmaceutical wastewater. The quantitative structure activity relationship models were used to predict the toxicity and biodegradability; meanwhile, the biological toxicity was tested by the method of dehydrogenase activity (DHA) as well as luminescent bacteria and biodegradability was measured by shaking experiment. The proposed system was applied to predict and evaluate toxicity and biodegradability of toluene, acetone, isopropanol and dichloromethane in pharmaceutical wastewater. The results showed that the actual measured values fitted well with the calculated values. The microtoxicity of toluene was the highest and the degr...

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала. This study assesses the comparative sensitivity and possibility of obtaining fast results of various methods of biotesting for several surfactants: Tween 85, sodium dodecyl sulfate (SDS), Fairy dishwashing gel, and Mif washing powder. The following test organisms are used for the study: luminescent bacteria Photobacterium phosphoreum (Beijerinck), preparation of Ecolum luminescent bacteria, unicellular algae Scenedesmus quadricauda (G.M. Smith), infusorian Paramecium caudatum (Ehrenberg), and crustacean Daphnia magna (Straus). It has been revealed that Fairy dishwashing gel possesses the strongest toxicity against the studied test objects. Daphnia and algae are most sensitive to the effects of Fairy and SDS, protozoan and luminescent bacteria are most sensitive to SDS, and Ecolum is most sensitive to Mif washing powder. The tested aquatic organisms and Ecolum are most tolerant to the effect of Tween 85.

2,4-DCP is a high-toxicity phenol compound, which is difficult to remove, harmful to the health of people and seriously influences the aquatic ecosystems. In this study, the degradation of 2,4-DCP using UV/persulfate (UV/PS) process was investigated for the first time. The results showed pseudo-first-order rate constants of 2,4-DCP photo-degradation by UV/PS was 35.1 × 10−3 min−1. The reaction rate constants increased with pH increasing from 5 to 7 and then decreased at pH 8. Different anions (Cl−, HCO3− and NO3−) in water presented different effects on the photo-degradation reaction. The photo-degradation rates of 2,4-DCP in three actual water conditions (Xidong water works, Xijiu reservoir, Henshan reservoir) were higher than in the ultrapure water. Two possible (hydroxylated and dechlorinated) pathways for the degradation of 2,4-DCP by UV/PS were proposed. The luminescent bacteria inhibition rate greatly decreased with the concentration of 2,4-DCP decreasing in the reaction process.

Vibrio fischeri bioluminescence inhibition has been widely used to test acute toxicities of metals and organics contaminants. However, the differences of metals and organics acute toxicities to V. fischeri have not been compared. Here, four heavy metals (Zn2+, Cu2+, Cd2+, Cr6+) and five organics (phenol, benzoic acid, p-hydroxy benzoic acid, nitro-benzene and benzene) acute toxicities to V. fischeri were investigated. Heavy metals toxicities to V. fischeri were increased along with the reaction time, while the organics toxicities kept the same level in different reaction times. In order to explain the difference, the relative cell death rate of V. fischeri was detected. In metals toxicities tests, the bioluminescence inhibition rate of V. fischeri was found to be significantly higher than the relative cell death rate (P

Psychoactive drug diazepam is one of benzodiazepines widely used in human medicine. It has been found to be relatively resistant to chlorination and photolysis. Here we investigated the transformation mechanism of diazepam in aqueous solution through UV/chlorine and simulated sunlight/chlorine treatments. The results showed that the UV/chlorine and sunlight/chlorine processes significantly increased the degradation of diazepam in water. These observed degradations can be elucidated by in-situ generation of reactive species including hydroxyl radical (HO ), reactive chlorine species (RCS) and ozone (O3) during photolysis of chlorine. In the UV/chlorine treatment, the degradation efficiency of diazepam for HO , chlorine, UV and RCS reaction at 90 min was calculated to be 62.1%, 3.8%, 11.9% and 12.3%, respectively. In the simulated sunlight/chlorine treatment, the calculated degradation of 53.1%, 8.1% and 11.2% was attributed to HO , chlorine and RCS reaction, with negligible loss by O3 reaction and sunlight irradiation. In the UV/chlorine and sunlight/chlorine treatments, a total of 70 transformation products was detected using a high-resolution TripleTOF mass system. Six transformation pathways have been tentatively proposed for the diazepam, which includes hydroxylation, chlorination, hydrolyzation, N-demethylation, loss of phenyl group, benzodiazepine ring rearrangement and contraction. Most of the obtained transformation products were less toxic to aquatic organisms including fish, daphnia and green algae than diazepam itself according to the toxicity prediction tool, and did not cause significant changes in toxicity to luminescent bacteria.

The current study depicts the isolation of luminescent bacteria from fish and squid samples that were collected from Veraval fish harbour. From Indian mackerel, total 14 and from squid, total 23 bioluminescent bacteria were isolated using luminescence agar medium. Two bioluminescent bacteria with highest relative luminescence intensity PBR1 and PBL1 were selected. These two isolates were subjected to detailed biochemical characterization and were tested positive for 5 out of 13 biochemical tests. Furthermore, both PBR1 and PBL1 were able to ferment cellobiose, dextrose, fructose, galactose, maltose, mannose, sucrose and trehalose with acid production. Based on 16S rRNA partial gene sequence analysis, PBR1 was identified as Vibrio alginolyticus and PBL1 as V. rotiferianus. Antibiotic susceptibility test using paper-disc method showed that PBR1 and PBL1 were sensitive to chloramphenicol, ciprofloxacin, co-trimoxazole, gatifloxacin, levofloxacin, linezolid ad roxithromycin out of 18 antibiotics tested. Moreover, both strains were evaluated for their exopolysachharide (EPS) producing ability where PBR1 and PBL1 were able to yield 1.34 g% (w/v) and 2.45 g% (w/v) EPS respectively from 5 g% (v/v) sucrose concentration. Heavy metal toxicity assessment was carried out using agar well diffusion method with eight heavy metals and both the strains were sensitive to As(III), Cd(II), Ce(II), Cr(III), Cu(II), Hg(II) and while they showed resistance to Pb(II) and Sr(II). Based on these results, a study was conducted to demonstrate bio-removal of Pb and Sr by EPS of PBR1 and PBL1. Fourier transform infrared (FTIR) spectra revealed the functional groups of EPS involved in interaction with the heavy metals. Owing to the sensitivity for the remaining heavy metals, these bioluminescent bacteria can be used further for the development of luminescence-based biosensor.

The possibility of using coffee silverskin, an industrial waste from the coffee roasting process, as an antifungal feedstock in wood preservative formulations was investigated. Silverskin hot water extract and its antifungal properties in vitro against Rhodonia (Poria) placenta, Gloeophyllum trabeum, and Trametes versicolor were characterized, and its in vitro effects on wood decay caused by Coniophora puteana were analyzed. A kinetic luminescent bacteria test was performed using Aliivibrio fischeri to measure the acute ecotoxicity of the silverskin extracts. The antifungal test showed 60–70% growth inhibition of the studied fungi at higher concentrations—3%—but did not meet the high inhibition—100%—of the commercial wood preservative. The phenolic compounds, such as chlorogenic acid and its derivatives, and caffeine derivatives, were the main constituents of the silverskin extracts and considered the responsible compounds of the fungal inhibition. The silverskin extracts were significantly less toxic than the commercial copper-based wood preservative. Revalorization of silverskin from industrial residues does not perform as a wood preservative but it remains a potential source of antifungal chemicals for wood preservative formulations.

Chlorination is essential to provide safe drinking water. However, this process leads to the formation of disinfection byproducts (DBPs). In this study, tryptophan (Trp) has been selected as a precursor to conduct the chlorine disinfection. Moreover, the factors that affect the formation of trihalomethanes (THMs) and iodinated trihalomethanes (I-THMs) are investigated. The formation pathway of Trp chlorination is proposed based on the intermediate products identified. According to the experimental results, the formation of THMs and I-THMs during Trp chlorination fitted a new first-order kinetic model. The dosage of chlorine, temperature, pH and the ratio of bromide and iodide had major influence on the formation of THMs and I-THMs during chlorination. In addition, the inhibition of luminescent bacteria Vibrio fischeri in the water sample increased during Trp chlorination.

Ultraviolet (UV) photodegradation is increasingly applied to control volatile organic compounds (VOCs) due to its degradation capabilities for recalcitrant compounds. However, sometimes the UV photodegradation products are also toxic and can affect human health. Here, 10 VOCs at 150~200 ppm in air were treated using a laboratory-scale UV reactor with 185/254 nm irradiation, and the biotoxicity of their off-gas was studied by investigating their off-gas absorption solutions. The CO2 increase and VOC decrease were 39~128 ppm and 0~42 ppm, respectively, indicating that the VOCs and their products were mineralized in off-gas absorption solutions. The total organic carbon (TOC) of the absorption solutions are 4~20 mg∙L&minus, 1. Luminescent bacteria and Daphnia magna were used to detect the acute toxicity, and an umu assay was used to determine the genotoxic potential. Trichloroethylene showed a highest toxicity to luminescent bacteria, while chlorobenzene had the lowest toxicity. Water-soluble UV photodegradation products for styrene are very toxic to Daphnia magna. In the umu assay, the genotoxicities of off-gas absorption solutions of trichloroethylene, methylbenzene, ethyl acetate, butyl alcohol, and styrene were 51.26, 77.80, 86.89, 97.20, and 273.62 mg (4-NQO)&middot, L&minus, 1 respectively. In addition, the analysis of the genotoxicity/TOC and intermediates products indicated that the off-gas absorption solutions of styrene, trichloroethylene, and butyl alcohol contain many highly toxic substances.

In 2013, the “Qingdao oil pipeline explosion” released an estimated 2000 tons of oil into the environment. Sediment samples were collected from ten sites in Jiaozhou Bay and Shilaoren Beach to evaluate the influence of the spilled oil on the benthic environment 3 years after the oil spill accident. The compositions of oil, bacterial diversity and biotoxicity were examined in this study. The results showed that the concentration of total petroleum hydrocarbons (TPHs) peaked near the oil leak point and gradually decreased along the coastline, ranging from 21.5 to 133.2 μg/g. The distribution of polycyclic aromatic hydrocarbons (PAHs) was correlated with TPH, and naphthalenes were dominant in the 20 detected PAHs. The bacterial diversities in seriously polluted and slightly polluted sediments were completely different. As degrading bacteria, Alcanivorax and Lutibacter were the main genera at the oil-polluted sites. The analysis of biotoxicity by the luminescent bacteria method showed great differences among the polluted sites, the control site in Jiaozhou Bay, and the non-polluted site outside of Jiaozhou Bay. The biotoxicity also peaked at the site near the oil leak point. These results indicate that the oil spill that occurred 3 years ago still affects the environment and impacts the bacterial communities in the sediments. Electronic supplementary material The online version of this article (10.1186/s13568-018-0603-6) contains supplementary material, which is available to authorized users.

In this study, peroxydisulfate (PDS) was successfully activated by nanoscale zero-valent iron (nZVI) for the degradation of sulfamethoxazole (SMX, antibiotic frequently detected in the environment) in agricultural soils. The results indicated that the degradation of SMX was affected by the nZVI dose, the ratio of SMX/PDS, the ratio of soil/water and reaction temperature, and in cinnamon soils 87.6% of SMX degradation can be achieved within 4 h at 30 °C when the initial nZVI dose was 0.03 g g−1 soil, the molar ratio of SMX/PDS = 1/75 and the soil/water = 1/1. The results of radical scavenger experiments and electron spin resonance (ESR) tests showed that hydroxyl radical ( OH) was the dominant reactive species in this system. The ecotoxicity tests of the soil by germination test, luminescent bacteria experiment and enzyme activity test indicated that the ecotoxicity of soil after treatment was obviously lower than the contaminated soil. In addition, there was almost no effect on plant growth when compared with original soil. Furthermore, this system exhibited a great degradation capacity for SMX in different types of agricultural soils, and the degradation efficiencies of SMX in other four soils were 90.6% (yellow brown earths), 80.8% (brown earths), 86.5% (black soils) and 96.1% (red earths), respectively. This work provides an optional method for agricultural soil pollution control.

Biotic ligand model (BLM) was extended to predict the toxicity of inorganic arsenate (iAs(V)) to the luminescent bacteria, Aliivibrio fischeri. As the pH increased from 5 to 9, the HAsO42- form predominated more than the H2AsO4- form did, and the EC50[As]T (50% effective iAs(V) concentration) decreased drastically from 3554 ± 393 to 39 ± 6 μM; thus, the HAsO42- form was more toxic to A. fischeri than H2AsO4-. As the HPO42- activity increased from 0 to 0.44 mM, the EC50{HAsO42-} values (50% effective HAsO42- activity) increased from 31 ± 6 to 859 ± 128 μM, indicating that the toxicity of iAs(V) decreased, owing to the competition caused by the structural similarity between iAs(V) and phosphate ions. However, activities of Ca2+, Mg2+, K+, SO42-, NO3-, and HCO3- did not significantly affect the EC50{HAsO42-} values. The BLM was reconstructed to take into account the effects of pH and phosphate, and the conditional binding constants for H2PO4-, HPO42-, H2AsO4-, and HAsO42- to the active binding sites of A. fischeri were obtained; 3.424 for logKXH2PO4, 4.588 for logKXHPO4, 3.067 for logKXH2AsO4, and 4.802 for logKXHAsO4. The fraction of active binding sites occupied by iAs(V) to induce 50% toxicity (fmix50%) was found to be 0.616.

Acute toxicities of anaerobic ammonia oxidation (ANAMMOX) substrates and four antibiotics from pharmaceutical wastewaters on ANAMMOX process were reported. Individual and joint acute toxicity assays were performed using 50% inhibitory concentration (IC50). Results showed that IC50 values and their 95% confidence interval of ammonium chloride (A), sodium nitrite (B), penicillin G-Na (C), polymyxin B sulfate (D), chloramphenicol (E) and kanamycin sulfate (F) were 2708.9 (2247.9–3169.9), 1475.4 (1269.9–1680.9), 5114.4 (4946.4–5282.4), 10.2 (1.8–18.6), 409.9 (333.7–486.1) and 5254.1 (3934.4–6573.8) mg L−1 respectively, suggesting toxicities were in the order of D > E > B > A > C > F. Joint acute toxicities of bicomponent mixtures A and B, C and D, C and F, D and F were independent; D and E, E and F were additive while C and E were synergistic. Joint acute toxicities of multicomponent mixtures were synergistic or additive. Luminescent bacteria test is an easy and robust method for forecasting the feasibility of ANAMMOX process for pharmaceutical wastewater treatment.

The increasing application of nanoparticles (NPs) to a variety of new technologies has become a matter ofconcern due to the potential toxicity of these materials. Many questions about the fate of NPs in the environmentand the subsequent impact on ecosystems need to be answered. The aim of this work was to evaluate theecotoxicity of two alumina-based nanoceramics, γ-Al2O3 (NC) and Ni/ γ-Al2O3 (NiNC) by means of three differentstandardized tests: Biochemical Oxygen Demand (BOD5), bioassay with luminescent bacteria (Vibrio fischeri;Microtox), and bioassay on amphibian larvae (Rhinella arenarum) (AMPHITOX). BOD5 values of a verybiodegradable mixture (glucose/glutamic acid) decreased with the addition of NiNC(43.8%) and NC (31.6%)with respect to control samples (52.9%). Microtox test results indicated that NiNC presents higher toxicity thanNC, with EC50s values of 16.1% and 29.9% respectively; a reduced toxicity was observed, however, in presenceof organic matter, thus obtaining EC50s of 37.8% and 19.4%. The results of AMPHITOX test showed a significantincrease in the toxicity of both substances over time, the NiNC toxicity being greater than that of NC. The valuesof 96 h-LC50 and 504 h-LC50 determined for NiNC were 1.58 and 0.83 mg/L, respectively, and 14.5 and10.5 mg/L for NC samples. Amphibian larvae exhibited collapsed cavities, edema, axial flexures, and behavioralalterations as hyperkinesia and reduced movements. These results evidence the vulnerability of wildlife to xenobioticsand the need to develop specific standardized ecotoxicity tests in order to help environmental sustainabilityand natural species conservation. Fil: Svartz, Gabriela Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental; Argentina Fil: Papa, Mariana Inés. Instituto Nacional de Tecnología Industrial; Argentina Fil: Gosatti, Marina. Comisión Nacional de Energía Atómica. Gerencia Complejo Tecnológico Pilcaniyeu; Argentina Fil: Jordán, Marianela Paula. Instituto Nacional de Tecnología Industrial; Argentina Fil: Soldati, Analía Leticia. Comisión Nacional de Energía Atómica. Gerencia Complejo Tecnológico Pilcaniyeu; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Samter, Paula. Instituto Nacional de Tecnología Industrial; Argentina Fil: Guraya, María M.. Comisión Nacional de Energía Atómica. Gerencia Complejo Tecnológico Pilcaniyeu; Argentina. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; Argentina Fil: Perez Coll, Cristina Silvia. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Perez Catán, Soledad. Comisión Nacional de Energía Atómica. Gerencia Complejo Tecnológico Pilcaniyeu; Argentina

Since aminophosphonate-based herbicides like glyphosate are currently one of the most popular and widely applied active agent in agrochemistry, there is an urgent need for searching new compounds among this family with potential herbicidal activity, but exhibiting low toxicity against surrounding environment. Six new (5-nitrofurfuryl)-derived aminophosphonates were synthesized for the first time and apart from the only one example of N-benzylamino(5-nitrofuryl)-methylphosphonic acid, it was the first time in the history, when this class of compounds was prepared. Their prospective and real biological properties have been followed up by evaluation of their preliminary ecotoxicology. They have been then investigated in aspect of their phytotoxicity against oat (A. sativa) and common radish (R. sativus) exhibiting moderate-to-severe toxicity for these plants. The significant selectivity towards radish (up to 3 times greater toxicity against radish) was observed in some cases. Title compounds were also tested in terms of their toxicity for freshwater crustaceans H. incongruens (ostracods) and marine luminescent bacteria A. fischeri. Although their harmful action on ostracods was not too much elevated, they were found to be highly toxic for bacteria. Various aspects of their ecotoxicity are discussed in this paper.

A wide range of biological activities of aminophosphonates predisposes them to find applications as anticancer, antiviral, antimicrobial, antifungal, or herbicidal agents. Despite a number of positive aspects of the use of aminophosphonates, their applications may cause a risk to the environment, which is well exemplified by the case of glyphosate. Therefore, scientists see a pressing need to rate ecotoxicity of aminophosphonates. Nowadays, it is recommended to use comprehensive tools to carry out appropriate and effective risk assessments of toxic substances. For these purposes, tests based on the acute toxicity of the luminescent bacteria Aliivibrio fischeri, as well as the measurement of sub-chronic toxicity of the crustacean Heterocypris incongruens seem to be the most convenient. A series of five diphenyl N-arylamino(pyrrole-2-yl)methylphosphonates was synthesized and preliminary evaluation of their ecotoxicological properties was performed. In order to carry out such investigations, we applied the two biotests mentioned above. Results showed that the N-(4-nitrophenyl) derivative was the most toxic for bacteria in comparison to other tested compounds. As for crustaceans, N-phenyl and N-naphthyl derivatives were found to be the most harmful, simultaneously being relatively harmless for bacteria. Such a phenomenon are discussed in correlation with the literature, while its reason is discussed with respect to the aspect of structure of the tested compounds.

Although the production of compost from sewage sludge is well established in developed countries, the use of sludge-based compost may represent a source of pollutants. The present study assessed the levels of potentially harmful compounds in compost as well as their rates of decrease during composting. The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs), three fragrance compounds (OTNE, HHCB and AHTN) and triclosan were determined in the initial sewage sludge and in compost over the span of 1 year. Simultaneously, the toxicity to luminescent bacteria (Aliivibrio fischeri) and aryl hydrocarbon receptor reactivity of organic solvent extracts of sludge and compost samples were assessed. Higher PAH, fragrance compounds, and triclosan concentrations were found in sewage sludge from urban areas compared with rural regions, and the urban sludge was also more toxic than the rural sludge. The high pollutant concentrations in urban sludge raised the concentrations of these compounds in the raw materials for composting and in the resulting composts. The organic matter was decomposed by 65% during the composting process, and the measured toxic substances were decreased by a similar amount, with the exception of triclosan, which decreased by only 35%. The toxicity to A. fischeri decreased to a greater extent (90%) than did the organic matter, while the aryl hydrocarbon receptor reactivity decreased by only 35%. This lower decrease coincided with that of the aryl hydrocarbon receptor-reactive PAHs (37%).

The purpose of this study was to discuss the effect of the chemical structure of anionic and non-ionic surfactants and surface activity on toxicity. Single and binary mixtures of three ether carboxylic derivative sur- factants and three amine-oxide-based non-ionic surfactants were used. Toxicity was determined using three test organisms: freshwater crustaceans (Daphnia magna), luminescent bacteria (Vibrio fischeri), and microalgae (Selenastrum capricornutum). The toxicity of surfactants is related to the hydrophobic alkyl chain, the degree of eth- oxylation, and the critical micelle concentration of sur- factants. Relationships found agreed with the fact that the lower toxicity is shown by the shorter alkyl chain. There is a strong relation between surface activity and toxicity: the toxicity increased as the CMC of the surfactant or mixtures of surfactants decreased. Commercial products are formu- lated using surfactants mixtures, so it is important to know their behavior using an easily measured property: the least toxic mixtures were formed by the surfactants having lower individual toxicity. Around the CMC, our data show a synergism for the binary mixtures. The results have given rise to a classification of the different surfactants and their mixtures according to the organism test, as safe, harmful or toxic. V. fischeri was in general the most sensitive micro- organism to the toxic effect of the surfactants, followed by Daphnia magna, while Selenastrum capricornutum was more tolerant. These results can be useful for selecting technically efficient surfactants and their mixtures with a lower ecotoxicity on the aquatic environment.

Twelve kinds of lignite from different areas of China were used for the study of solid-phase biodenitrification. The amount of released carbon, rate of nitrate removal and acute toxicity were examined for all the lignite samples. The results showed that the averaged nitrate removal rates of lignite from Wangniutan and Zhangjiakou were higher than the others, which can reach above 30%. The averaged removal rates of lignite from Zhaotong, Aksu and Faku were more than 20%, and others were less than 10%. Lignite from Wangniutan, Zhangjiakou, Aksu and Faku were more suitable fillers as biodenitrification carbon for its less luminescent bacteria acute toxicity.

A photodegradation technology based on the combination of ultraviolet radiation with H2O2 (UV/H2O2) for degrading tri(chloroisopropyl) phosphate (TCPP) was developed. In ultrapure water, a pseudo-first order reaction was observed, and the degradation rate constant reached 0.0035 min−1 (R2 = 0.9871) for 5 mg L−1 TCPP using 250 W UV light irradiation with 50 mg L−1 H2O2. In detail, the yield rates of Cl− and PO43− reached 0.19 mg L−1 and 0.58 mg L−1, respectively. The total organic carbon (TOC) removal rate was 43.02%. The pH value of the TCPP solution after the reaction was 3.46. The mass spectrometric detection data showed a partial transformation of TCPP into a series of hydroxylated and dechlorinated products. Based on the luminescent bacteria experimental data, the toxicity of TCPP products increased obviously as the reaction proceeded. In conclusion, degradation of high concentration TCPP in UV/H2O2 systems may result in more toxic substances, but its potential application for real wastewater is promising in the future after appropriate optimization, domestication and evaluation.

Triclosan, one of the most widely used disinfectants, has been found to be toxic to animals and human beings. In this paper, triclosan was degraded on TiO 2 nanotube arrays, using a photoelectrocatalytic (PEC) process under UV illumination, with Na 2 SO 4 as the supporting electrolyte. The effect of bias potential was investigated and the results showed that 0 V was the most appropriate potential for the degradation of triclosan. In 30 min, 78.7% of triclosan had degraded during the PEC process. Intermediate analysis showed that 2,7-dichlorodibenzodioxin (DCDD) had formed during the degradation. The toxicity change during the PEC process was investigated using a luminescent bacteria test, with the results demonstrating that the toxicity of the reaction liquid decreased at the beginning and subsequently increased to a stable level. The indications were that some intermediates such as 2,7-dichlorodibenzodioxin was more toxic and stable than triclosan in the solution.

The aim of the present study was the chemical characterization of some medically relevant essential oils (tea tree, clove, cinnamon bark, thyme, and eucalyptus) and the investigation of antibacterial effect of the components of these oils by use of a direct bioautographic method. Thin-layer chromatography (TLC) was combined with biological detection in this process. The chemical composition of the oils was determined by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Eucalyptol (84.2%) was the main component of the essential oil of eucalyptus, eugenol (83.7%) of clove oil, and trans-cinnamic aldehyde (73.2%), thymol (49.9%), and terpinen-4-ol (45.8%) of cinnamon bark, thyme and tea tree oils, respectively. Antibacterial activity of the separated components of these oils as well as of their pure main components (eucalyptol, eugenol, trans-cinnamic aldehyde and thymol) was observed against the Gram-negative luminescence gene-tagged plant pathogenic bacterium Pseudomonas syringae pv...

Crude oil is a complex mixture of petroleum hydrocarbons (PHC) with distinct chemical, physical and toxicological properties relevant for contaminated site risk assessment. Ecotoxicological effects of crude oil distillation fractions on luminescent bacteria (Vibrio fischeri), earthworms (Dendrobaena hortensis) and invertebrates (Heterocypris incongruens) were tested using two spiked soils and their elutriates. Fraction 2 (F2) had an equivalent carbon number (ECN) range of >10 to 16, and F3 from >16 to 39. F2 showed a substantially higher ecotoxicological effect than F3 for Vibrio and Dendrobaena. In contrast, severe inhibition of Heterocypris by the poorly soluble F3 is attributed to mechanical organ blockage. Immediate sequestration of PHC to the organic matter-rich soil effected reduced toxicity for all organisms. This study indicates that a more differentiated consideration (i) of PHC mixtures based on ECN range and (ii) of model soil properties employed for ecotoxicity testing should be included into PHC-contaminated site risk assessment.

Ethyl-4-aminobenzoate (Et-PABA) is currently used as a substitute for 4-aminobenzoate (PABA) in sunscreens and anesthetic ointments. Despite its widespread use and hydrophilicity, Et-PABA has never been found in environmental waters. This study, probed the occurrence of Et-PABA in both seawater and drinking water sources in Hong Kong, and evaluated its transformation products (TPs) and environmental fate via cumulative potency and photocatalytic profile analyses. Another 11 UV filters used in skin-care products were also studied. Et-PABA was not detected in any water sample. Four other UV filters were dominant at ng/L level in both seawater and drinking water sources. UHPLC-QTOF-MS was used to elucidate the structure of TPs. With high resolution accurate mass data and fragment rationalization, 11 Et-PABA TPs were characterized, including seven intermediates firstly proposed as TPs; two compounds were reported for the first time. It is proposed that photocatalysis induces transformation pathways of (de)hydroxylation, demethylation and molecular rearrangement. Luminescent bacteria tests showed decreasing toxicity with increasing irradiation of Et-PABA, suggesting that irradiation TPs are less toxic than the parent compound. Transformation of Et-PABA appears to explain why Et-PABA has not been detected in the natural environment.

Fenamic acids, one important type of non-steroidal anti-inflammatory drugs, are ubiquitous in environmental matrices. Thus it is of high significance to know the fate of them during chlorination disinfection considering their potential toxicity to the environment and humans. In the present study, the chlorination kinetics of three fenamic acids, i.e. mefenamic acid (MEF), tolfenamic acid (TOL) and clofenamic acid (CLO), were examined at different pHs, which followed second-order reaction under studied conditions. The studied fenamic acids degraded fast, with the largest apparent second-order rate coefficient ( k app ) values of 446.7 M −1 s −1 (pH 7), 393.3 M −1 s −1 (pH 8) and 360.0 M −1 s −1 (pH 6) for MEF, TOL and CLO, respectively. The transformation products (TPs) were identified by solid-phase extraction-liquid chromatography-mass spectrometer and ion-pair liquid-liquid extraction and injection port derivatization-gas chromatography-mass spectrometer. Despite different numbers of TPs were detected for each studied fenamic acid through these two analytical methods, the types of TPs were almost the same; chlorine substitution, oxidation and the joint oxidation with chlorine substitution are transformation reactions involved in chlorination. Moreover, the total toxicity of the TPs was assayed based on luminescent bacteria. Under different pHs, the different types of TPs might form, resulting in the varied total toxicity. The toxicity of all three fenamic acids chlorinated at pH of 8 was greater than those at pHs of 6 and 7. This study provided the information about the kinetics, transformation and toxicity of three fenamic acids during water chlorination, which is important to the drinking water safety.

Modern analytical test methods increasingly detect anthropogenic organic substances and their transformation products in water samples and in the environment. The presence of these compounds might pose a risk to the aquatic environment. To determine a possible (eco)toxicological risk, aquatic samples are tested using various bioassays, including sub-organismic assays such as the luminescent bacteria inhibition test, the acetylcholinesterase inhibition test, and the umu-test. The effect-directed analysis (EDA) combines physicochemical separation methods with biological (in vitro) tests. High-performance thin-layer chromatography (HPTLC) has proved to be particularly well suited for the separation of organic compounds and the subsequent analysis of effects by the application of the biotests directly on the surface of the HPTLC plate. The advantage of using HPTLC in comparison to high-performance liquid chromatography (HPLC) for EDA is that the solvent which is used as a mobile phase during chromatography is completely evaporated after the separation and therefore can no longer influence the applied bioassays.

The environmental impact of two biocide-free antifouling paints, fluoropolymer and silicone types, painted on a test cylinder was assessed using a battery of ecotoxicity test and chemical analyses for organic micro-pollutants such as perfluoroalkyl substances (PFAS). A biocide paint containing zinc pyrithione (ZnPT2) and cuprous oxide was assessed as a positive control. A standardized laboratory rotating-cylinder method using each test cylinder with artificial seawater was performed for 45 days. After 1 h rotation, the leaked seawater was subjected for bioassay and chemical analyses twice weekly. The seawater extracts from the biocide paint showed adverse effects on bacteria, algae, and crustaceans, but those from the biocide-free paints did not. The leakage seawater from biocide-free paints, after 7-day continuous rotation, contained the same concentration levels of PFAS as blank seawater used to conduct the tests. Thus, no significant toxicities of the biocide-free paints were found under the conditions...