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1.
Environ Monit Assess ; 193(5): 254, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33835283

RESUMEN

This study evaluated toxicity level of produced water effluent on indigenous organisms in Delta state, Nigeria. Four test organisms, Vibrio fischeri, Palaemonetes africanus, Tympanosomas fuscatus, and Tilapia guineensis, were selected for toxicity assessment using effluent streams from treated produced water and water from the produced water recipient environment. Representative samples of treated produced water effluent were collected from the bulk header within the oil terminal and within the discharge environment. Acute toxicity tests were carried out using the Microtox® Model 500. The results of the acute toxicity tests on V. fischeri revealed that the average inhibitive concentration (IC50) for treated produced water at 5 min and 15 min was 22.20% and 31.17% and the no effect concentration (NOEC) and low effect concentration (LOEC) at 5 min and 15 min was 5.63% and 5.63%, respectively. In the recipient water, at 5 min and 15 min, IC50 estimate was of 33.57% and 47.02% while the NOEC and LOEC were 5.63% and 5.63%, respectively. The average IC50, NOEC, LOEC, toxicity unit-acute (TUa), toxicity unit-chronic (TUc), and toxicity factor (TF) toxicity values for P. africanus were 80.606%, 66.990%, and 73.13%; 1.24, 1.49, and 2066.82; 42.24%, 6.165%, and 11.936%; 2.37, 16.21, and 25.54 in treated and recipient water, respectively. In T. guineensis, average IC50, LOEC, NOEC, TUa, TUc, and TF were 4.86%, 1.786%, 1.059%, 20.60, 94.34, and 269.72 and 5.090%, 1.828%, 1.070%, 19.65, 93.46, and 282.78 for treated produced water and recipient environment, respectively. There was no mortality in T. fuscatus var radula exposed to both treated produced water and recipient water.


Asunto(s)
Contaminantes Químicos del Agua , Aliivibrio fischeri , Monitoreo del Ambiente , Nigeria , Agua , Contaminantes Químicos del Agua/toxicidad
2.
Environ Monit Assess ; 193(5): 268, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33860380

RESUMEN

The objective of this study was to determine the ecological risk created by metal contents of the surface sediments of Atikhisar dam, Çanakkale, NW Turkey. Enrichment factor (EF) and geoaccumulation index (Igeo) were calculated to determine anthropogenic effects. Ecological risk was assessed using the modified potential ecological risk index (mPER), with its levels being evaluated using the modified ecological risk index (mER). Toxic effects were determined using the toxic risk index (TRI). The ecological risk indices were mapped to provide their spatial distributions. Our findings indicate that enrichment was very high for Hg and significant for Pb, Tl, Cd, and As. The following mER pattern was detected: Hg > Cd > TI > As > Pb > Ni > Cr > Co > Zn > Mn > V. Hg and Cd exhibited extremely high and very high ecological risks, respectively, while TI and As had a significant ecological risk, with Pb exerting a medium ecological risk. Hg, Pb, Tl, Cd, As, Cr, Ni, Zn, and Cu were enriched via anthropogenic effects exceeding their natural concentration levels. Due to their high toxic effects, Hg, Cd, Tl, As, and Pb were identified as the very high risk elements. Mining, household wastes, agriculture, and natural mineral deposits were identified as the possible sources of the potential ecological risk.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados/análisis , Metales Pesados/toxicidad , Medición de Riesgo , Turquia , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
3.
Braz J Biol ; 82: e230147, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33729329

RESUMEN

Metals and agrochemicals are among the main aquatic contaminants, being able to trigger oxidative stress in exposed organisms. The objective of this work was to evaluate the correlation between the level of oxidative stress biomarkers in Aegla crabs (Crustacea, Anomura) with (i) the set of metals present in the streams sediment and (ii) with land uses of three hydrographic basins. The study was carried out in streams (≤ 2nd order) of hydrographic basins in southern Brazil (Basins of Rio Suzana, Rio Ligeirinho-Leãozinho and Rio Dourado). In these streams were quantified the land uses and Cu, Cr, Cd, Fe, Mn and Zn concentrations in the sediment. The enzymes Catalase (CAT) and Glutathione Reductase (GR), as well as the level of membrane lipid peroxidation (TBARS), were analyzed in adult females. The PCA analysis showed that the distribution of metals was different between the basins. Cd, Cr and Fe were correlated positively with CAT and negatively with TBARS and GR. The Dourado basin had the lowest concentrations of these three metals and the highest levels of TBARS. However, in Dourado basin there is predominance of agriculture land use, and TBARS was positively correlated with agricultural land use. Besides in Dourado basin, GR activity was higher than in the others basins, indicating a compensatory response in relation to CAT inhibition. The basins of Suzana and Ligeirinho-Leãozinho rivers had lower TBARS values, which may be due to the induction of CAT in response to metals accumulated in sediment. In summary, this work indicates that in the basins with a higher concentration of toxic metals there is an adaptive response of CAT induction, which reduces TBARS in Aegla. On the other hand, in the basin with lower metallic contamination, TBARS occurrence was primarily influenced by agricultural land use.


Asunto(s)
Anomuros , Metales Pesados , Contaminantes Químicos del Agua , Agricultura , Animales , Biomarcadores/metabolismo , Brasil , Monitoreo del Ambiente , Femenino , Metales Pesados/análisis , Estrés Oxidativo , Ríos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(3): 418-423, 2021 Mar 06.
Artículo en Chino | MEDLINE | ID: mdl-33730838

RESUMEN

Haloacetaldehydes (HALs), as emerging disinfection by-products in drinking water, are the third largest group by weight of identified disinfection by-products (DBPs) in drinking water. The formation of HALs is associated with the level of natural organic matter and halide in the source water, the treatment process of drinking water and the type of disinfectant. Recent studies have shown that HALs are more cytotoxic and genotoxic than regulated trihalomethanes and halo-acetic acids in drinking water. Currently, only a few countries and regions have set limit values for trichloroacetaldehyde with high detection rate in drinking water. However, there is growing evidence that unregulated HALs have a higher potential risk to human health compared to regulated HALs. This paper reviews the current research progress on the formation and transformation, cytotoxicity and genotoxicity of HALs in drinking water, and looks forward to the problems that should be paid attention in the future toxicological research of HALs in order to support the development of scientific drinking water standards.


Asunto(s)
Desinfectantes , Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Desinfectantes/toxicidad , Desinfección , Agua Potable/análisis , Humanos , Trihalometanos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
5.
Sci Total Environ ; 771: 144565, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33736145

RESUMEN

Environmental stressors are assessed through methods that quantify their impacts on a wide range of metrics including species density, growth rates, reproduction, behaviour and physiology, as on host-pathogen interactions and immunocompetence. Environmental stress may induce additional sublethal effects, like mutations and epigenetic signatures affecting offspring via germline mediated transgenerational inheritance, shaping phenotypic plasticity, increasing disease susceptibility, tissue pathologies, changes in social behaviour and biological invasions. The growing diversity of pollutants released into aquatic environments requires the development of a reliable, standardised and 3R (replacement, reduction and refinement of animals in research) compliant in vitro toolbox. The tools have to be in line with REACH regulation 1907/2006/EC, aiming to improve strategies for potential ecotoxicological risks assessment and monitoring of chemicals threatening human health and aquatic environments. Aquatic invertebrates' adult stem cells (ASCs) are numerous and can be pluripotent, as illustrated by high regeneration ability documented in many of these taxa. This is of further importance as in many aquatic invertebrate taxa, ASCs are able to differentiate into germ cells. Here we propose that ASCs from key aquatic invertebrates may be harnessed for applicable and standardised new tests in ecotoxicology. As part of this approach, a battery of modern techniques and endpoints are proposed to be tested for their ability to correctly identify environmental stresses posed by emerging contaminants in aquatic environments. Consequently, we briefly describe the current status of the available toxicity testing and biota-based monitoring strategies in aquatic environmental ecotoxicology and highlight some of the associated open issues such as replicability, consistency and reliability in the outcomes, for understanding and assessing the impacts of various chemicals on organisms and on the entire aquatic environment. Following this, we describe the benefits of aquatic invertebrate ASC-based tools for better addressing ecotoxicological questions, along with the current obstacles and possible overhaul approaches.


Asunto(s)
Ecotoxicología , Contaminantes Químicos del Agua , Animales , Organismos Acuáticos , Humanos , Invertebrados , Reproducibilidad de los Resultados , Células Madre , Contaminantes Químicos del Agua/toxicidad
6.
Chemosphere ; 271: 129775, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33736227

RESUMEN

In the marine environment, organisms are exposed to a high and increasing number of different contaminants that can interact among them. In addition, abiotic factors can change the dynamics between contaminants and organisms, thus increasing or even decreasing the toxic effect of a particular compound. In this study, the effects of caffeine (CAF) and functionalized multi-walled carbon nanotubes (f-MWCNTs) induced in the clam Ruditapes philippinarum were evaluated, acting alone and in combination (MIX), under two temperature levels (18 and 21 °C). To assess the impact of such compounds, their interaction and the possible influence of temperature, biochemical and histopathological markers were investigated. The effects of f-MWCNTs and caffeine appear to be clearly negative at the control temperature, with lower protein content in contaminated clams and a significant decrease in their metabolism when both pollutants were acting in combination. Also, at control temperature, clams exposed to pollutants showed increased antioxidant capacity, especially when caffeine was acting alone, although cellular damages were still observed at CAF and f-MWCNTs treatments. Increased biotransformation capacity at 18 °C and MIX treatment may explain lower caffeine concentration observed. At increased temperature differences among treatments were not so evident as at 18 °C, with a similar biological pattern among contaminated and control clams. Higher caffeine accumulation at MIX treatment under warming conditions may result from clams' inefficient biotransformation capacity when exposed to increased temperatures.


Asunto(s)
Bivalvos , Nanotubos de Carbono , Contaminantes Químicos del Agua , Animales , Cafeína/toxicidad , Nanotubos de Carbono/toxicidad , Estrés Oxidativo , Temperatura , Contaminantes Químicos del Agua/toxicidad
7.
Sci Total Environ ; 769: 144302, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33736255

RESUMEN

Sediments are considered an ultimate sink for microplastic (MPs) but knowledge on MPs impacts on the benthic organisms is still limited. A microcosm experiment was performed to assess the effect of MPs on two sediment-dwelling bivalve species that differ in terms of their life¬styles and feeding behaviors (the cockle Cerastoderma glaucum and the Baltic clam Limecola balthica). Fitness of both bivalves, their vertical distribution in the sediment and activity at the sediment-water interface were studied following addition of PE microspheres of three different size fractions (63-75, 150-180 and 250-300 µm) in two concentrations (0.1 and 0.5% sediment dwt) to the sediment surface. Bivalve survival was generally high and did not vary significantly among treatments. Both bivalve species captured MPs but no significant effect on their body conditions and energy reserves was observed. However, some behavioural alterations were found. The near-surface-dwelling C. glaucum emerged from the sediment less often and in lower numbers suggesting lower activity in sediments amended with large and medium MPs served in higher concentration. Also vertical distribution of deeper-dwelling L. balthica differed among treatments. The clam penetrated deeper sediment layers in microcosms treated with MPs than in the control (on average 62% of the total number of bivalves found in the sediment layer 2-4 cm vs. 65% in the upper 2 cm) which may suggest an avoidance behaviour or escape reaction in response to MPs addition to the topmost sediment. Total sediment community oxygen consumption was significantly higher in MPs-amended sediments than in the control, with the highest rates in treatment with the largest microspheres. However, oxygen uptake increase seemed to be unrelated to addition of MPs per se, suggesting rather an interaction between MPs and bivalves. The need for future studies on MPs effects on benthic community structure and functioning is highlighted.


Asunto(s)
Bivalvos , Contaminantes Químicos del Agua , Animales , Países Bálticos , Sedimentos Geológicos , Microplásticos , Plásticos/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
8.
Sci Total Environ ; 769: 145218, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33736268

RESUMEN

Bisphenol A (BPA) is a well-known xenoestrogen, and UV/H2O2 advanced oxidation process (AOP) is one of the most effective technologies to remove BPA from water. Using BPA spiked tap water, a batch-scale photochemical experiment was conducted to investigate whether BPA can pose a genotoxicity concern during the medium pressure (MP) UV/H2O2 treatment and the post-chloramination. Samples at different UV exposure and post-chloramination durations were collected and analyzed by CALUX® gene reporter assays regarding estrogen receptor α (ERα) and p53 transcriptional activity. MP UV/H2O2 process did not cause extra estrogenic effects from the degradation of BPA, whereas genotoxicity occurred when the treated water was exposed with monochloramine. Seven frequently reported nitrogenous disinfection byproducts (N-DBPs) were detected, but none of them were responsible for the observed genotoxicity. Employed with gas chromatography-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), four compounds possibly contributed to the genotoxicity were tentatively identified and two of them with aminooxy- or cyano- group were considered as "new" N-DBPs. This study demonstrated that by-products differ from their parent compounds in toxicity can be formed in the UV oxidation with post-disinfection process, which should become a cause for concern.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Compuestos de Bencidrilo , Bioensayo , Desinfección , Peróxido de Hidrógeno , Fenoles , Rayos Ultravioleta , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
9.
Sci Total Environ ; 768: 144991, 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33736306

RESUMEN

In this work, we have experimentally and computationally investigated the process of hydrolysis and photolysis of cephalosporin antibiotics with ceftriaxone (CEF) as a model compound. The CEF hydrolysis was investigated in ultrapure and natural water, at 25 ± 1 °C and 4 ± 1 °C in the dark. It was found that CEF after 100 and 900 days at 25 ± 1°C and 4 ± 1 °C, respectively practically completely removed from ultrapure water. The CEF hydrolysis in natural water was five and three times slower at 25 ± 1 °C and 4 ± 1 °C, respectively than in ultrapure water. Further, the efficiency of direct photolysis (solar/UVA-B) and solar/H2O2 treatment of CEF was investigated. Under UVA-B radiation 95.6% of CEF was removed after 60 min, while for the same time of solar radiation degradation was practically not observed (only 3.2%). Also, the effects of different concentrations of H2O2 (0-150 mM) in the presence/absence of solar radiation were studied. The most efficient solar/H2O2 treatment was in the presence of 90 mM H2O2, whereby 66.8% of CEF was removed after 60 min (41.8% by indirect photolysis, 21.8% by H2O2-oxidation, and 3.2% by direct photolysis). Radial distribution functions (RDF) provided information about the distribution of water around the CEF molecule. Aside from the RDF, investigation of intramolecular noncovalent interactions and calculations of bond dissociation energies for hydrogen abstraction enabled understanding of degradation mechanism of CEF. In order to investigate sensitivity of CEF towards the radical attacks, the concept of Fukui functions was used. The structures of intermediates and degradation pathways were suggested by UHPLC-LTQ OrbiTrap MS and density functional theory calculations. Toxicity assessments showed that intermediates formed during hydrolysis exerted only mild cell growth effects in selected cell lines.


Asunto(s)
Ceftriaxona , Contaminantes Químicos del Agua , Antibacterianos/toxicidad , Peróxido de Hidrógeno , Hidrólisis , Cinética , Fotólisis , Rayos Ultravioleta , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
10.
Sci Total Environ ; 768: 144326, 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33736309

RESUMEN

Contaminants of emerging concern (CECs) are ubiquitous, present in complex chemical mixtures, and represent a threat to the Great Lake ecosystem. Mitigation strategies are needed to protect populations of key species, but knowledge about ecological and biological effects of CECs at the population level are limited. In this study, we combined laboratory data on CEC effects at the individual-level with in-situ CEC concentration data in a walleye (Sander vitreus) population model to simulate the effectiveness of different CEC mitigation strategies in the Maumee River and Lake Erie. We compared the effectiveness of moderate mitigation (50% reduction in exposure level) of an entire watershed versus intensive mitigation (reduction of exposure to a level that does not affect walleye) of single river sites for three CEC mixture scenarios (agricultural, urban, and combined). We also explored the impact of hypothetical chemical toxicokinetics (the time course of chemicals in walleye) on the relative effectiveness of the mitigation strategies. Our results suggest that when CECs impact fecundity, single-site mitigation is more effective when it focuses on spawning sites and nearby downstream sites that are substantially impaired. Our simulations also suggest that chemical toxicokinetics are important when evaluating single-site mitigation strategies, but that population characteristics, such as stage-specific mortality rate, are more important when evaluating watershed mitigation strategies. Results can be used to guide fisheries management, such as choosing habitat restoration sites, and identify key knowledge gaps that direct future research and monitoring.


Asunto(s)
Percas , Contaminantes Químicos del Agua , Agricultura , Animales , Ecosistema , Monitoreo del Ambiente , Lagos , Ríos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
11.
Sci Total Environ ; 768: 144750, 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33736315

RESUMEN

Recent urban public water supply contamination events emphasize the importance of screening treated drinking water quality after distribution. In vitro bioassays, when run concurrently with analytical chemistry methods, are effective tools to evaluating the efficacy of water treatment processes and water quality. We tested 49 water samples representing the Chicago Department of Water Management service areas for estrogen, (anti)androgen, glucocorticoid receptor-activating contaminants and cytotoxicity. We present a tiered screening approach suitable to samples with anticipated low-level activity and initially tested all extracts for statistically identifiable endocrine activity; performing a secondary dilution-response analysis to determine sample EC50 and biological equivalency values (BioEq). Estrogenic activity was detected in untreated Lake Michigan intake water samples using mammalian (5/49; median: 0.21 ng E2Eq/L) and yeast cell (5/49; 1.78 ng E2Eq/L) bioassays. A highly sensitive (anti)androgenic activity bioassay was applied for the first time to water quality screening and androgenic activity was detected in untreated intake and treated pre-distribution samples (4/49; 0.93 ng DHTEq/L). No activity was identified above method detection limits in the yeast androgenic, mammalian anti-androgenic, and both glucocorticoid bioassays. Known estrogen receptor agonists were detected using HPLC/MS-MS (estrone: 0.72-1.4 ng/L; 17α-estradiol: 1.3-1.5 ng/L; 17ß-estradiol: 1.4 ng/L; equol: 8.8 ng/L), however occurrence did not correlate with estrogenic bioassay results. Many studies have applied bioassays to water quality monitoring using only relatively small samples sets often collected from surface and/or wastewater effluent. However, to realistically adapt these tools to treated water quality monitoring, water quality managers must have the capacity to screen potentially hundreds of samples in short timeframes. Therefore, we provided a tiered screening model that increased sample screening speed, without sacrificing statistical stringency, and detected estrogenic and androgenic activity only in pre-distribution Chicago area samples.


Asunto(s)
Disruptores Endocrinos , Contaminantes Químicos del Agua , Animales , Bioensayo , Chicago , Disruptores Endocrinos/análisis , Monitoreo del Ambiente , Estrógenos/análisis , Michigan , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Calidad del Agua
12.
Huan Jing Ke Xue ; 42(4): 1830-1838, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33742818

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), two typical persistent organic pollutants, are the research focus due to their mutagenesis, carcinogenesis, teratogenesis, and bioaccumulation. The content distribution and residual characteristics of PAHs and PCBs were investigated in the sediments from the Sanya River. Source apportionment was further explored based on the analysis of the spatial distribution, and the ecological risk evaluation was carried out with the sediment quality criteria and standards. The results indicate that the content of ΣPAHs and ΣPCBs in the sediment range from 265.00 µg·kg-1 to 6735.00 µg·kg-1 and 1.75 µg·kg-1 to 92.75 µg·kg-1, with relatively high contents in the east and west river upstream, respectively, which had a strong correlation with the industrial structure and river movement of the study area. The composition and source apportionment demonstrate that PAHs originated mostly from the combustion of petroleum with low PAHs, and haxa-CB and hepta-CB are the predominant PCBs congeners, primarily resulting from the migration of PCBs in the capacitor. The ecological risk evaluation demonstrates that the biotoxic effect of the PAHs is not obvious, with a low ecological risk. However, several PAHs monomers exceeded the standard significantly in some sampling sites, which should be of concern due to its serious threat of exposure to organisms. The probability of a biotoxic effect of PCBs is 10%-50%, which occasionally produces a negative ecological effect.


Asunto(s)
Bifenilos Policlorados , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Sedimentos Geológicos , Bifenilos Policlorados/análisis , Bifenilos Policlorados/toxicidad , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Medición de Riesgo , Ríos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
13.
Huan Jing Ke Xue ; 42(3): 1496-1502, 2021 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-33742947

RESUMEN

Ephedrine (EPH) is an alkaloid commonly used to relieve nasal congestion caused by colds, allergic rhinitis, rhinitis, and sinusitis, and to control bronchial asthma. It is also be used as a raw material in the manufacture of methamphetamine. Although the distribution of EPH in surface waters has been widely studied, its uptake, internal distribution, and toxicokinetic processing in exposed organisms have not been well investigated. In this study, we investigated the uptake, disposition, and toxicokinetics of EPH in zebrafish (Danio rerio) in a semi-static exposure system. EPH was consistently detected in zebrafish biological samples, with the highest concentrations of 84.97 ng·g-1 detected in the brain tissue of fish in the high treatment group. Over the 14-d exposure period, the relative abundance of mean concentrations of EPH in biological samples generally followed the order of brain > ovary > liver > intestine > muscle. The uptake rate constants (Ku), elimination rate constants (Ke), and half-lives of EPH in the biological tissues were in the ranges 0.23-570.31 L·(kg·d)-1, 1.22-6.11 d-1, and 0.12-0.57 d, respectively. The observed bioconcentration factor (BCFo) and kinetically-derived bioconcentration factor (BCFk) were similar, ranging 0.24-337.33 L·kg-1 and 0.13-316.43 L·kg-1, respectively. These results are helpful for understanding the behavior of psychoactive substances in aquatic organisms and have directive significance for studying their toxicity and ecological risks to aquatic organisms.


Asunto(s)
Contaminantes Químicos del Agua , Pez Cebra , Animales , Organismos Acuáticos , Efedrina/toxicidad , Femenino , Toxicocinética , Contaminantes Químicos del Agua/toxicidad
14.
Sci Total Environ ; 764: 142921, 2021 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-33757243

RESUMEN

Coastal areas are final recipients of various contaminants including pesticides. The effects of pesticides on non-target organisms are often unclear, especially at environmentally relevant concentrations. This study investigated the impacts of insecticide imidacloprid (IMI) and fungicide propiconazole (PRO), some of the most detected pesticides in the Arcachon Bay in France. This work also included the research of propiconazole nanoformulation (nanoPRO). The effects were assessed studying the development of the early life stages of the Pacific oyster (Magallana gigas). Oyster embryos were exposed for 24, 30, and 42 h (depending on the endpoint) at 24 °C to environmentally relevant concentrations of the two pesticides as well as to nanoPRO. The research focused on sublethal endpoints such as the presence of developmental malformations, alterations of locomotion patterns, or changes in the gene expression levels. No developmental abnormalities were observed after exposure to environmental concentrations detected in the Arcachon Bay in recent years (maximal detected concentration of IMI and PRO were 174 ng/L and 29 ng/L, respectively). EC50 of PRO and nanoPRO were comparable, 2.93 ±â€¯1.35 and 2.26 ±â€¯1.36 mg/L, while EC50 of IMI exceeded 200 mg/L. IMI did not affect larval behavior. PRO affected larval movement trajectory and decreased average larvae swimming speed (2 µg/L), while nanoPRO increased the maximal larvae swimming speed (0.02 µg/L). PRO upregulated especially genes linked to reactive oxygen species (ROS) production and detoxification. NanoPRO effects on gene expression were less pronounced - half of the genes were altered in comparison with PRO. IMI induced a strong dose-response impact on the genes linked to the detoxification, ROS production, cell cycle, and apoptosis regulation. In conclusion, our results suggest that current pesticide concentrations detected in the Arcachon Bay are safe for the Pacific oyster early development, but they might have a small direct effect via altered gene expressions, whose longer-term impacts cannot be ruled out.


Asunto(s)
Crassostrea , Contaminantes Químicos del Agua , Animales , Biomarcadores , Francia , Expresión Génica , Larva , Neonicotinoides , Nitrocompuestos , Triazoles , Contaminantes Químicos del Agua/toxicidad
15.
Molecules ; 26(4)2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33673249

RESUMEN

The low cost ß-zeolite and ethylenediamine modified ß-zeolite (EDA@ß-zeolite) were prepared by self-assembly method and used for Cu(II) removal from contaminated aqueous solution. Removal ability of ß-zeolite toward Cu(II) was greatly improved after ethylenediamine (EDA) modification, the removal performance was greatly affected by environmental conditions. XPS results illustrated that the amide group played important role in the removal process by forming complexes with Cu(II). The EDA@ß-zeolite showed desirable recycling ability. The finding herein suggested that the proposed composite is a promising and suitable candidate for the removal of Cu(II) from contaminated natural wastewater and aquifer.


Asunto(s)
Cobre/aislamiento & purificación , Etilenodiaminas/química , Contaminantes Químicos del Agua/aislamiento & purificación , Zeolitas/química , Adsorción , Cobre/toxicidad , Humanos , Agua/química , Contaminantes Químicos del Agua/toxicidad
16.
BMC Bioinformatics ; 22(1): 151, 2021 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-33761866

RESUMEN

BACKGROUND: A number of predictive models for aquatic toxicity are available, however, the accuracy and extent of easy to use of these in silico tools in risk assessment still need further studied. This study evaluated the performance of seven in silico tools to daphnia and fish: ECOSAR, T.E.S.T., Danish QSAR Database, VEGA, KATE, Read Across and Trent Analysis. 37 Priority Controlled Chemicals in China (PCCs) and 92 New Chemicals (NCs) were used as validation dataset. RESULTS: In the quantitative evaluation to PCCs with the criteria of 10-fold difference between experimental value and estimated value, the accuracies of VEGA is the highest among all of the models, both in prediction of daphnia and fish acute toxicity, with accuracies of 100% and 90% after considering AD, respectively. The performance of KATE, ECOSAR and T.E.S.T. is similar, with accuracies are slightly lower than VEGA. The accuracy of Danish Q.D. is the lowest among the above tools with which QSAR is the main mechanism. The performance of Read Across and Trent Analysis is lowest among all of the tested in silico tools. The predictive ability of models to NCs was lower than that of PCCs possibly because never appeared in training set of the models, and ECOSAR perform best than other in silico tools. CONCLUSION: QSAR based in silico tools had the greater prediction accuracy than category approach (Read Across and Trent Analysis) in predicting the acute toxicity of daphnia and fish. Category approach (Read Across and Trent Analysis) requires expert knowledge to be utilized effectively. ECOSAR performs well in both PCCs and NCs, and the application shoud be promoted in both risk assessment and priority activities. We suggest that distribution of multiple data and water solubility should be considered when developing in silico models. Both more intelligent in silico tools and testing are necessary to identify hazards of Chemicals.


Asunto(s)
Daphnia , Relación Estructura-Actividad Cuantitativa , Contaminantes Químicos del Agua , Animales , China , Simulación por Computador , Contaminantes Químicos del Agua/toxicidad
17.
Environ Pollut ; 277: 116860, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33714129

RESUMEN

Plastic particles, which are formed from routinely used plastics and their fragments, have become a new pollutant raising widespread concern about their potential effects. Several studies have been conducted to examine their toxicity, but the effects of nano-sized plastic fragments on freshwater organisms remain largely unclear and need to be further investigated. In this study, larval tilapia were first exposed to 100 nm polystyrene nanoparticles (PS-NPs, 20 mg/L) for seven days and then returned to freshwater without PS-NPs for another seven days in order to determine the toxic effects of PS-NPs at both transcriptomic and metabolomic levels. A total of 203 significantly changed metabolites, and 2,152 differentially expressed unigenes were identified between control and PS-NP treatment groups, control and recovery groups, as well as treatment and recovery groups. Our data suggested that PS-NPs induced abnormal metabolism of glycolipids, energy, and amino acids in tilapia after short-term exposure. Additionally, PS-NPs caused disturbed signaling, as suggested by the transcriptomic results. Different transcriptomic and metabolomic levels between the treatment group and recovery group indicated a persistent impact of PS-NPs on tilapia. The presence of adhesion molecule-related differentially expressed genes (DEGs) suggested that PS-NPs might cause early inflammatory responses. Notably, the detection of chemical stimulus involved in the sensory perception of smell was the most severely impacted biological process. Our work systemically studied the ecotoxicity of nano-sized plastics in aquatic creatures at the molecular and genetic levels, serving as a basis for future investigations on the prevention and treatment of such pollutants.


Asunto(s)
Nanopartículas , Tilapia , Contaminantes Químicos del Agua , Animales , Microplásticos , Nanopartículas/toxicidad , Poliestirenos/toxicidad , Transcriptoma , Contaminantes Químicos del Agua/toxicidad
18.
Environ Pollut ; 277: 116873, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33714789

RESUMEN

Triclocarban (TCC), an antibacterial agent widely used in personal care products, can affect embryonic development. However, the specific molecular mechanism of TCC-induced embryonic developmental damage remains unclear. In this study, TCC exposure was found to increase the expression of tmbim4 gene in zebrafish embryos. The tmbim4 mutant embryos are more susceptible to TCC exposure than wild-type (WT) embryos, with tmbim4 overexpression reducing TCC-induced embryonic death in the former. Exposure of tmbim4 mutant larvae to 400 µg/L TCC substantially increased apoptosis in the hindbrain and eyes. RNA-sequencing of WT and tmbim4 mutant larvae indicated that knockout of the tmbim4 gene in zebrafish affects the autophagy pathway. Abnormalities in autophagy can increase apoptosis and TCC exposure caused abnormal accumulation of autophagosomes in the hindbrain of tmbim4 mutant zebrafish embryos. Pretreatment of TCC-exposed tmbim4 mutant zebrafish embryos with autophagosome formation inhibitors, substantially reduced the mortality of embryos and apoptosis levels. These results indicate that defects in the tmbim4 gene can reduce zebrafish embryo resistance to TCC. Additionally, apoptosis induced by abnormal accumulation of autophagosomes is involved in this process.


Asunto(s)
Contaminantes Químicos del Agua , Pez Cebra , Animales , Apoptosis , Autofagia , Carbanilidas , Embrión no Mamífero , Desarrollo Embrionario , Larva , Contaminantes Químicos del Agua/toxicidad
19.
Ecotoxicol Environ Saf ; 214: 112092, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33690008

RESUMEN

Over the last two decades, effect-directed analysis (EDA) gained importance as a seminal screening tool for tracking biological effects of environmental organic micro-pollutants (MPs). As EDA using high-performance liquid chromatography and bioassays is costly and time consuming, recent implementations of this approach have combined high-performance thin-layer chromatography (HPTLC) with effect-based methods (EBMs) using cell-based bioassays, enabling the detection of estrogenic, androgenic, genotoxic, photosystem II (PSII)- inhibiting, and dioxin-like sample components on a HPTLC plate. In the present study, the developed methodologies were applied as a HPTLC-based bioassay battery, to investigate toxicant elimination efficiency of wastewater treatment plants (WWTPs), and to characterize the toxic potential of landfill leachates. Activity levels detected in untreated landfill leachates, expressed as reference compound equivalence (EQ) concentration, were up to 16.8 µg ß-naphthoflavone-EQ L-1 (indicating the degree of dioxin-like activity), 1.9 µg estradiol-EQ L-1 (estrogenicity) and 8.3 µg diuron-EQ L­1 (PSII-inhibition), dropping to maximal concentrations of 47 ng ß-naphthoflavone-EQ L-1, 0.7 µg estradiol-EQ L-1 and 53.1 ng diuron-EQ L-1 following treatment. Bisphenol A (BPA) is suggested to be the main contributor to estrogenic activity, with concentrations determined by the planar yeast estrogen screen corresponding well to results from chemical analysis. In the investigated WWTP samples, a decrease of estrogenic activity of 6-100% was observed following treatment for most of the active fractions, except of a 20% increase in one fraction (Rf = 0.568). In contrast, androgenicity with concentrations up to 640 ng dihydrotestosterone-EQ L-1 was completely removed by treatment. Interestingly, genotoxic activity increased over the WWTP processes, releasing genotoxic fractions into receiving waters. We propose this combined HPTLC and EBM battery to contribute to an efficient, cheap, fast and robust screening of environmental samples; such an assay panel would allow to gain an estimate of potential biological effects for prioritization prior to substance identification, and its routine application will support an inexpensive identification of the toxicity drivers as a first tier in an EDA strategy.


Asunto(s)
Bioensayo/métodos , Contaminantes Químicos del Agua/toxicidad , Purificación del Agua , Compuestos de Bencidrilo , Cromatografía en Capa Delgada/métodos , Monitoreo del Ambiente/métodos , Estrógenos/toxicidad , Fenoles , Dibenzodioxinas Policloradas/análisis , Aguas Residuales/análisis , beta-naftoflavona
20.
Ecotoxicol Environ Saf ; 214: 112099, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33714139

RESUMEN

Although fish are widely confirmed to be susceptible to heavy metals (HMs) contamination in sediments, this bioconversion haven't been detailed. This is especially the case in karst areas, where HMs are less stably retained in the sediments and are more bioavailable. Therefore, we surveyed representative karst rivers in Liuzhou, China, in order to study the relationship between the speciations of seven HMs in the sediments with their bioaccumulation in wild fish. The results showed that the HMs in sediments are all below their permissible exposure limit (PEL), but Cd and Zn are significantly higher than soil basline. Most HMs are in residual fraction, while their exchangeable fractions are present in extremely low proportions. The concentration of Zn, Cr and Cd in some fish are above their maximum recommended limit (MRL). The concentrations of most of the HMs in the fish are significantly correlated with the levels in the sediments and given the higher correlation coefficients for their carbonate-bound phase, this phase can be seen to play a critical role in HMs bioconversion. However, the presence of this phase in low proportions enables other phases, especially oxidizable form, to play a greater role in HMs bioaccumulation. Apart from Do, HMs in the fish samples are significantly correlated with multiple environmental factors, demonstrating environmental fluctuations can manipulate HMs bioconversion from sediments; however, their significance depend heavily on the proportion of particular species. HMs in reducible and oxidizable fraction are more important in regulating, rather than promoting, their bioconversion during environmental fluctuations. Fluctuations in EC, TDS and pH can increase the impacts of HMs in carbonate-bound fraction on their bioconversion. Given the higher background values of EC and TDS and lower pH values during the monsoon period, careful attention should be paid to the increased bioconversion of HMs in karst rivers during this season.


Asunto(s)
Monitoreo del Ambiente , Peces/fisiología , Metales Pesados/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Bioacumulación , China , Sedimentos Geológicos , Metales Pesados/análisis , Medición de Riesgo , Ríos , Estaciones del Año , Suelo , Contaminantes Químicos del Agua/análisis
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