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1.
J Hazard Mater ; 472: 134484, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38723484

RESUMEN

To quantify the possible impact of different wood protection techniques on the aquatic environment, we applied a tiered Integrated Testing Strategy (ITS) on leachates obtained from untreated (UTW) Norway spruce (Picea abies), specimens treated with a copper-ethanolamine-based preservative solution, complying with the Use Class 3 (UC3), and specimens thermally modified (TM). Different maturation times in water were tested to verify whether toxicant leaching is time-dependent. Tier I tests, addressing acute effects on Aliivibrio fischeri, Raphidocelis subcapitata, and Daphnia magna, evidenced that TM toxicity was comparable or even lower than in UTW. Conversely, UC3 significantly affected all species compared to UTW, also after 30 days of maturation in water, and was not considered an environmentally acceptable wood preservation solution. Tier II (effects on early-life stages of Lymnea auricularia) and III (chronic effects on D. magna and L. auricularia) performed on UTW and TM confirmed the latter as an environmentally acceptable treatment, with increasing maturation times resulting in decreased adverse effects. The ITS allowed for rapid and reliable identification of potentially harmful effects due to preservation treatments, addressed the choice for a less impacting solution, and can be effective for manufacturers in identifying more environmentally friendly solutions while developing their products.

2.
Environ Res ; 252(Pt 4): 119140, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38751003

RESUMEN

Feather analysis is an ethical and effective method for assessing the exposure of wild birds to environmental contamination due to trace elements and organic pollutants. We used feather to monitor the exposure to three toxic and non-essential metals (Hg, Cd, and Pb) and rare earth elements (REEs) of Kentish plover (Charadrius alexandrinus) breeding in different coastal areas (Veneto, Emilia-Romagna, Marche, Abruzzo, and Apulia) along the Italian coast of the Adriatic Sea. Feathers (n = 113) were collected from April to June. Feather concentrations evidenced a significant exposure to Hg (13.05 ± 1.71 mg kg-1 dw) and REEs (447.3 ± 52.8 ng g-1 dw) in the Kentish plover breeding in Veneto (n = 21) compared to the other coastal areas, with several individuals showing Hg concentrations above the adverse effect (5 mg kg-1 dw) and high-risk (9.14 mg kg-1 dw) thresholds reported for birds. Higher REE concentrations compared to Marche (n = 29), Abruzzo (n = 11) and Apulia (n = 13) were also reported for birds breeding in Emilia-Romagna (474.9 ± 41.9 ng g-1 dw; n = 29). The exposure to Cd and Pb was low in all the coastal areas, and only a few samples (n = 6 and n = 4 for Cd and Pb, respectively) exceeded the adverse effect thresholds (0.1 and 4 mg kg-1 for Cd and Pb, respectively). A significant sex-related difference was observed for REE-concentrations, with females showing higher concentration than males. These data highlight the need to monitor the exposure of the Kentish plover to Hg and REEs, especially in the northern basin of the Adriatic Sea, since these elements might negatively affect species' reproductive success and threaten its conservation.

4.
Environ Res ; 228: 115837, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37028535

RESUMEN

Neonicotinoids (NEOs) and active pharmaceuticals ingredients (API) are contaminants widely diffused worldwide, causing increasing concern for potential adverse effects on wildlife. However, research on these contaminants have focused on target and non-target invertebrates, while information on potential effects in terrestrial mammals is lacking. We performed preliminary non-invasive monitoring of NEOs and API in a suburban and agricultural area using hair of the Red fox. The Red fox is a widely diffused mesopredator in Europe, and its plasticity in feeding habits makes it an excellent indicator for assessing exposure to environmental contamination. We observed the presence of NEOs in many Red fox hair samples (n = 11), including imidacloprid (IMI), acetamiprid (ACE), and clothianidin (CLO). The highest quantified concentrations were 6.4 ng g-1 dry weight (dw), 6.7 ng g-1 dw, and 0.9 ng g-1 dw for IMI, ACE, and CLO, respectively. The targeted APIs included non-steroidal anti-inflammatory drugs (NSAIDs) and antidepressants. APIs were less frequently detected than NEOs, and the compounds with the highest prevalence were the NSAID ketoprofen (36%), the antidepressant sertraline (36%), and its active metabolite norsertraline (27%). The presence of human pharmaceuticals such as the NSAID ibuprofen and the antidepressants sertraline, fluoxetine, and their active metabolites norsertraline and norfluoxetine suggest environmental contamination due to untreated and partially treated wastewater discharged in surface waters and soils of the study area. The detection and quantification of ketoprofen and flunixin also suggest the possible use of contaminated manure on farmland. Findings indicate that hair may be used for monitoring environmental exposure to NEOs and provide evidence that hair is a good marker of exposure for antidepressants and certain NSAIDs, including ibuprofen, ketoprofen, and flunixin.


Asunto(s)
Insecticidas , Cetoprofeno , Humanos , Animales , Zorros , Sertralina , Ibuprofeno , Neonicotinoides/toxicidad , Antidepresivos , Italia , Antiinflamatorios no Esteroideos , Cabello , Preparaciones Farmacéuticas
5.
Mar Pollut Bull ; 190: 114846, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36965268

RESUMEN

Exhaust Gas Cleaning Systems (EGCS), operating in open-loop mode, continuously release acidic effluents (scrubber waters) to marine waters. Furthermore, scrubber waters contain high concentrations of metals, polycyclic aromatic hydrocarbons (PAHs), and alkylated PAHs, potentially affecting the plankton in the receiving waters. Toxicity tests evidenced significant impairments in planktonic indicators after acute, early-life stage, and long-term exposures to scrubber water produced by a vessel operating with high sulphur fuel. Acute effects on bacterial bioluminescence (Aliivibrio fischeri), algal growth (Phaeodactylum tricornutum, Dunaliella tertiolecta), and copepod survival (Acartia tonsa) were evident at 10 % and 20 % scrubber water, while larval development in mussels (Mytilus galloprovincialis) showed a 50 % reduction at ∼5 % scrubber water. Conversely, larval development and reproductive success of A. tonsa were severely affected at scrubber water concentrations ≤1.1 %, indicating the risk of severe impacts on copepod populations which in turn may result in impairment of the whole food web.


Asunto(s)
Copépodos , Diatomeas , Mytilus , Contaminantes Químicos del Agua , Animales , Plancton , Biomarcadores Ambientales , Agua , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis
6.
Bull Environ Contam Toxicol ; 110(1): 2, 2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36484834

RESUMEN

Seabirds accumulate mercury (Hg) due to their long-life span together with their high trophic position. A Hg monitoring in Venice's Lagoon using three seabird species occupying different trophic habitat (Thalasseus sandvicensis, Ichthyaetus melanocephalus, and Chroicocephalus ridibundus) confirmed that fledgelings might effectively be used as sentinels of Hg bioavailability. The significant differences in Hg residues in feathers observed among the species highlighted a possible differential exposure due to different diets, with C. ridibundus accumulating more Hg than the other species. Average residues in feathers were not above the threshold associated with adverse effects on birds (5 mg kg- 1). Nevertheless, a large part of the C. ridibundus individuals (58%) exceeded the adverse effect level, underlining the need for strengthening Hg monitoring. Seabirds indeed may provide relevant insight on Hg transfer in food webs and a better picture of the hazards to men when bird species forage on species exploited for human consumption.


Asunto(s)
Charadriiformes , Mercurio , Animales , Masculino , Humanos , Mercurio/análisis , Monitoreo del Ambiente , Plumas/química , Aves
7.
Mar Environ Res ; 181: 105761, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36206640

RESUMEN

Neonicotinoids (NEOs) are neurotoxic pesticides acting as nicotinic acetylcholine receptor agonists. NEOs' efficacy against pest insects has favoured their spreading use in agriculture, but their proven effectiveness against non-target insects in terrestrial and aquatic ecosystems also raised concern over their environmental impact. Crustaceans were often studied for the impacts of NEOs due to their economic values and nervous' system similarity with insects. However, most studies on crustaceans focused on acute effects or exposure of early-life stages, while long-term effects were seldom explored. The present study aimed to assess the potential long-term effects of four commercially available NEOs on the reproduction and offspring of the calanoid copepod Acartia tonsa, a key species in the food webs of several coastal and estuarine environments. NEOs were confirmed as potent interferents of copepod reproduction. The first-generation compound acetamiprid significantly inhibited egg production and hatching ratio at 10 ng L-1, while larval survival and development were affected at 81 ng L-1. Similarly, the first-generation compound thiacloprid significantly inhibited the hatching ratio and larval development at 9 ng L-1, while it did not affect egg production and larval survival. Second-generation compounds were less toxic than acetamiprid and thiacloprid: clothianidin affected significantly only larval development of the offspring at 62 ng L-1, while thiamethoxam was not toxic at both the tested concentrations (8 ng L-1 and 84 ng L-1). These data evidenced that effects on copepods may occur at concentrations below the chronic aquatic life benchmarks reported by USEPA for acetamiprid (2100 ng L-1) and thiacloprid (970 ng L-1), suggesting that long-term effects of NEOs have been underestimated. A comparison with environmental concentrations evidenced that NEO-mediated effects on copepods are more liable in coastal areas receiving discharge from wastewater treatment plants or diffuse inputs from agricultural land during pesticide application periods.


Asunto(s)
Copépodos , Insecticidas , Plaguicidas , Animales , Insecticidas/toxicidad , Insecticidas/análisis , Ecosistema , Neonicotinoides/toxicidad , Reproducción , Larva
8.
Toxics ; 10(4)2022 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-35448419

RESUMEN

Neonicotinoids (NEOs) are neurotoxic pesticides widely used in agriculture due to their high effectiveness against pest insects. Despite their widespread use, very little is known about their toxicity towards marine organisms, including sensitive and ecologically relevant taxa such as copepods. Thus, we investigated the toxicity of five widely used NEOs, including acetamiprid (ACE), clothianidin (CLO), imidacloprid (IMI), thiacloprid (THI), and thiamethoxam (TMX), to assess their ability to inhibit the larval development of the copepod Acartia tonsa. The more toxic NEOs were ACE (EC50 = 0.73 µg L-1), TMX (EC50 = 1.71 µg L-1) and CLO (EC50 = 1.90 µg L-1), while the less toxic compound was IMI (EC50 = 8.84 µg L-1). Early life-stage mortality was unaffected by NEOs at all of the tested concentrations. The calculated toxicity data indicated that significant effects due to ACE (EC20 = 0.12 µg L-1), THI (EC20 = 0.88 µg L-1) and TMX (EC20 = 0.18 µg L-1) are observed at concentrations lower than established chronic aquatic life benchmarks reported by USEPA for freshwater invertebrates. Nevertheless, since environmental concentrations of NEOs are generally lower than the threshold concentrations we calculated for A. tonsa, the effects may be currently of concern only in estuaries receiving wastewater discharges or experiencing intense runoff from agriculture.

9.
Environ Sci Pollut Res Int ; 29(21): 31002-31024, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35113376

RESUMEN

Laboratory testing with spiked sediments with organic contaminants is a valuable tool for ecotoxicologists to study specific processes such as effects of known concentrations of toxicants, interactions of the toxicants with sediment and biota, and uptake kinetics. Since spiking of the sediment may be performed by using different strategies, a plethora of procedures was proposed in the literature for spiking organic chemicals onto sediments to perform ecotoxicological analyses. In this paper, we reviewed the scientific literature intending to characterise the kind of substrates that were used for spiking (i.e. artificial or field-collected sediment), how the substrates were handled before spiking and amended with the organic chemical, how the spiked sediment was mixed to allow the homogenisation of the chemical on the substrate and finally how long the spiked sediment was allowed to equilibrate before testing. What emerged from this review is that the choice of the test species, the testing procedures and the physicochemical properties of the organic contaminant are the primary driving factors affecting the selection of substrate type, sediment handling procedures, solvent carrier and mixing method. Finally, we provide recommendations concerning storage and characterization of the substrate, equilibrium times and verification of both equilibration and homogeneity.


Asunto(s)
Sedimentos Geológicos , Contaminantes Químicos del Agua , Ecotoxicología , Sedimentos Geológicos/química , Compuestos Orgánicos , Contaminantes Químicos del Agua/análisis
10.
Sci Total Environ ; 821: 153473, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35093362

RESUMEN

Exposure to active pharmaceutical ingredients (APIs) from both human and veterinary sources is an increasing threat to wildlife welfare and conservation. Notwithstanding, tracking the exposure to pharmaceuticals in non-target and sensitive vertebrates, including birds, is seldom performed and relies almost exclusively on analysing internal organs retrieved from carcasses or from experimentally exposed and sacrificed birds. Clearly, this excludes the possibility of performing large-scale monitoring. Analysing feathers collected from healthy birds may permit this, by detecting APIs in wild birds, including protected and declining species of waterbirds, without affecting their welfare. To this end, we set up a non-destructive method for analysing the presence of non-steroidal anti-inflammatory drugs (NSAIDs), selective serotonin reuptake inhibitors (SSRIs) and noradrenaline reuptake inhibitors (SNRIs) in the feathers of fledglings of both the Mediterranean gull (Ichtyaetus melanocephalus) and the Sandwich tern (Thalasseus sandvicensis). The presence of several NSAIDs and SSRIs above the method quantification limits have confirmed that feathers might be a suitable means of evaluating the exposure of birds to APIs. Moreover, the concentrations indicated that waterbirds are exposed to NSAIDs, such as diclofenac, ibuprofen and naproxen, and SSRIs, such as citalopram, desmethylcitalopram, fluvoxamine and sertraline, possibly due to their widespread use and incomplete removal in wastewater treatment plants (WWTPs). The active ingredient diclofenac raises a the primary concern for the ecosystem and the welfare of the waterbirds, due to its high prevalence (100% and 83.3% in Mediterranean gull and Sandwich tern, respectively), its concentrations detected in feathers (11.9 ng g-1 and 6.7 ng g-1 in Mediterranean gull and Sandwich tern, respectively), and its documented toxicity toward certain birds.


Asunto(s)
Plumas , Drogas Veterinarias , Animales , Antiinflamatorios no Esteroideos , Antidepresivos , Ecosistema , Humanos , Inhibidores Selectivos de la Recaptación de Serotonina
11.
Environ Res ; 206: 112637, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-34973939

RESUMEN

Neonicotinoids are one of the most diffusely used classes of pesticides whose level of danger toward non-target invertebrate and vertebrate species has raised increasing concern in the last decades. Among vertebrates, birds are particularly susceptible to unintentional neonicotinoid poisoning since they can be exposed through different pathways, including ingestion of dressed seeds, sucking of contaminated pollen, ingestion of sprayed insects, predation on contaminated aquatic and terrestrial preys. In the present study, we investigated the possible exposure of seabirds by measuring the residues of five neonicotinoids (acetamiprid, clothianidin, imidacloprid, thiacloprid and thiamethoxam) in samples of pooled feathers collected from fledglings of the strictly piscivorous Sandwich tern (Thalasseus sandvicensis) and the mixotrophic species Mediterranean gull (Ichthyaetus melanocephalus). At least one neonicotinoid was quantified in all the Mediterranean gull samples (n = 11) and 89% of the analysed Sandwich tern samples (n = 36). The active principles with the highest quantification rates were imidacloprid (100% in Mediterranean gulls and 58% in Sandwich terns) and clothianidin (100% in Mediterranean gulls and 61% in Sandwich terns), while thiacloprid was the less frequently detected pesticide (<20% of samples in both species). Mean concentrations ± standard error for imidacloprid, clothianidin and thiamethoxam were 8.8 ± 1.4, 4.5 ± 0.19 and 0.16 ± 0.02 ng g-1 for the Mediterranean gull, and 5.8 ± 0.55, 0.60 ± 0.08 and 0.36 ± 0.03 ng g-1for the Sandwich tern, respectively. Our data evidenced the exposure of seabirds to neonicotinoids and the further need to investigate the extent of neonicotinoid contamination in non-agricultural ecosystems.


Asunto(s)
Ecosistema , Insecticidas , Animales , Hábitos , Insecticidas/análisis , Neonicotinoides , Nitrocompuestos , Tiametoxam
12.
Environ Res ; 204(Pt B): 112152, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34606838

RESUMEN

Rare Earth Elements (REEs) are increasingly exploited for crucial new technologies, and their massive use in the past decades has significantly increased their environmental concentrations. Although their effects have been extensively studied in vitro and in vivo in model species, little is known of their accumulation and potential toxic effects in wildlife, including waterbirds. In the present work, we measured the concentrations of REEs in feathers of young Sandwich tern (Thalasseus sandvicensis) about 16-20 days old to assess whether the accumulation of these elements may be a concern in Venice's Lagoon, one of the most important wetlands of the Mediterranean area for breeding and migrating birds. The REE concentrations detected in the Sandwich tern were the highest among those reported in the literature for bird's feathers (940.9 ± 223.0 ng g-1), although in the study area industrial activities related to REEs mining, processing and disposal are absent. In particular, Lanthanum (La) was more abundant in the feathers than other REEs and accounted for 73-97% of total REEs detected. Analysis of bird's food indicated that diet is a relevant route of exposure to REEs for young terns; however, concentration in fishes are relevantly higher than in the feathers for all REEs other than La. The study evidenced the need to collect more information concerning the occurrence of REEs both in the abiotic matrices (i.e. water and sediments) and in living organisms of different trophic levels to improve the general knowledge concerning the fate of REEs in the aquatic ecosystems.


Asunto(s)
Charadriiformes , Metales de Tierras Raras , Animales , Ecosistema , Plumas/química , Metales de Tierras Raras/análisis , Minería
13.
Environ Sci Pollut Res Int ; 26(25): 26146-26158, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31280439

RESUMEN

Nanotechnology provides innovative and promising solutions for the conservation of cultural heritage, but the development and application of new nano-enabled products pose concerns regarding their human health and environmental risks. To address these issues, we propose a sustainability framework implementing the Safe by Design concept to support product developers in the early steps of product development, with the aim to provide safer nano-formulations for conservation, while retaining their functionality. In addition, this framework can support the assessment of sustainability of new products and their comparison to their conventional chemical counterparts if any. The goal is to promote the selection and use of safer and more sustainable nano-based products in different conservation contexts. The application of the proposed framework is illustrated through a hypothetical case which provides a realistic example of the methodological steps to be followed, tailored and iterated along the decision-making process.


Asunto(s)
Nanotecnología , Medición de Riesgo/métodos , Humanos , Administración de la Seguridad
14.
Arch Environ Contam Toxicol ; 77(2): 223-236, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31134306

RESUMEN

A sequential TIE procedure combining in a single framework Phase I manipulations and Phase II methods, including chemical analyses and complementary Phase I treatments, was proposed for characterization and identification of toxicants of concern in estuarine environments. Interstitial water was chosen as test matrix and embryo-larval development with the bivalve Crassostrea gigas as toxicity endpoint. TIE treatments included addition of Ulva rigida and elution through zeolite column for addressing effects due to ammonia, addition of EDTA and elution through a Cation-Exchange Solid-Phase Extraction column for characterize metals, and elution through two different type of polymers (XAD and DPA) with different affinity for polar and nonpolar organic pollutants. Chemical analyses concerned determination of ammonia and trace elements in the untreated sample and after manipulation intended to remove or modify bioavailability of ammonia and metals. The "hybrid" Phase I-Phase II TIE sequence proved to be a reliable and effective tool for the identification of main toxicant of concern in a highly toxic and contaminated interstitial water sample, also in presence of high concentration of potential confounding factors (ammonia). The addition of U. rigida was the more reliable treatment for the removal of ammonia, due to the concurrent release of particles and potentially toxic elements, such as Ba, Rb, and Tl by zeolite column, which may increase toxicity in the post-column sample. The combined use of polymers with different affinity for the various classes of organic pollutants was essential to identify the contribution of polar organic compounds to the observed toxicity.


Asunto(s)
Ecotoxicología/métodos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Amoníaco/análisis , Animales , Crassostrea/efectos de los fármacos , Ácido Edético , Estuarios , Femenino , Masculino , Metales/análisis , Extracción en Fase Sólida/métodos , Ulva/efectos de los fármacos , Contaminantes Químicos del Agua/química
15.
Ecotoxicol Environ Saf ; 179: 62-70, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31026751

RESUMEN

A non-invasive study of trace element accumulation in tail feathers of the Kentish plover (Charadrius alexandrinus) was performed along the coastline of the northern littoral strip of the Venice Lagoon, with the aim to verify whether contamination may be a factor affecting conservation status of Kentish plover populations. Body burdens in feathers of 11 trace elements including toxic metals/metalloids and essential elements (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Se, V, Zn) were quantified by ICP-MS, then concentrations were normalized to feather's age calculated using ptilochronology in order to obtain daily deposition rates. Mercury emerged as a major threat to the conservation of the species, since average feather concentration was clearly above the adverse-effect threshold associated with impairment in the reproductive success in a number of bird species. Also Cd and Se occurred at levels that may impact on the conservation status of the studied species at local scale, even if to a lesser extent than Hg. Gender-related differences in trace element accumulation emerged only for As, although for this element the risks associated to environmental exposure seem to be negligible.


Asunto(s)
Arsénico/análisis , Charadriiformes/metabolismo , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Plumas/química , Mercurio/análisis , Oligoelementos/análisis , Animales , Femenino , Masculino , Factores Sexuales
16.
Ecotoxicology ; 27(9): 1237-1248, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30191521

RESUMEN

A whole-sediment test with the infaunal amphipod Monocorophium insidiosum has been developed to assess the long-term effects exerted by sediment contamination on survival, growth rates and attainment of sexual maturity. Juvenile amphipods were exposed for 28 days to a control sediment (native sediment) and three sediment samples collected in sites of the Venice Lagoon, characterized by contamination levels ranging from low to moderate, and absence of acute toxicity toward amphipods. Growth rate was estimated as daily length (µm d-1) and weight increments (µg d-1). The long-term exposure to the test sediments affected significantly both growth rate and attainment of sexual maturity of the females of M. insidiosum. In contrast, survival was high and uniform among all the samples, despite the contamination gradient. The results suggest growth to be the more reliable and statistically relevant endpoint. Attainment of sexual maturity, although allowed the identification of detrimental effects, was affected by a higher among-replicates variance as compared with growth rates, and thus less reliable than growth for the identification of impairments. The significant impairments observed both on growth and attainment of maturity evidenced the need to address the monitoring, also in the Lagoon of Venice, towards the assessment of the long-term effects on benthic species.


Asunto(s)
Anfípodos/fisiología , Sedimentos Geológicos , Pruebas de Toxicidad Crónica/métodos , Contaminantes Químicos del Agua/toxicidad , Animales , Monitoreo del Ambiente , Pruebas de Toxicidad Crónica/normas
18.
Ecotoxicol Environ Saf ; 147: 251-259, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28846930

RESUMEN

The combined effects of different salinity and temperature levels on the toxicity of Arsenic (As) were studied on the embryonic development of the oyster Crassostrea gigas. A standardized embryotoxicity test was performed to assess the interactive effects of these stressors, in a full factorial design experiment including a range of salinities (15, 19, 24, 28 and 32), temperatures (16, 20, 24, 28 and 32°C) and As concentrations (100, 300, 600, 1200, 2400µgL-1). The embryotoxicity endpoint was about the determination of normal larvae development rates at various conditions, and median effect concentration (EC50) determination for each As exposure condition. Results showed that toxicity induced by As was characterized by retardation of embryonic development observing toxic effects at lower concentrations than previously reported studies. The presence of As in seawater resulted in a narrower range of tolerance to both salinity and temperature. These findings bring new insights on the impacts of a common contaminant on an important shellfish species having a planktonic early life stage development, with potential implications for population survival and ecosystem functioning in a changing environment.


Asunto(s)
Arsénico/toxicidad , Crassostrea/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Salinidad , Temperatura , Contaminantes Químicos del Agua/toxicidad , Animales , Crassostrea/embriología , Relación Dosis-Respuesta a Droga , Larva/efectos de los fármacos , Dosificación Letal Mediana , Agua de Mar/química
19.
Ecotoxicol Environ Saf ; 123: 65-71, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26256248

RESUMEN

Chloramphenicol sodium succinate (CAP, C15H15Cl2N2 Na2O8) is a broad-spectrum antibiotic exhibiting activity against both Gram-positive and Gram-negative bacteria as well as other groups of microorganisms only partially removed by conventional activated sludge wastewater treatment plants. Thus, CAP and its metabolites can be found in effluents. The present work deals with the photocatalytic degradation of CAP using TiO2 as photocatalyst. We investigated the optimization of reaction contact time and concentration of TiO2 considering CAP and its by-products removal as well as effluent ecotoxicity elimination. Considering a CAP real concentration of 25mgL(-1), kinetic degradation curves were determined at 0.1, 0.2, 0.4, 0.8, 1.6 and 3.2gL(-1) TiO2 after 5, 10, 30, 60 and 120min reaction time. Treated samples were checked for the presence of by-products and residual toxicity (V. fischeri, P. subcapitata, L. sativum and D. magna). Results evidenced that the best combination for CAP and its by-products removal could be set at 1.6gL(-1) of TiO2 for 120min with an average residual toxicity of approximately 10%, that is the threshold set for negative controls in most toxicity tests for blank and general toxicity test acceptability.


Asunto(s)
Antibacterianos/química , Cloranfenicol/análogos & derivados , Contaminantes Químicos del Agua/química , Aliivibrio fischeri/efectos de los fármacos , Aliivibrio fischeri/metabolismo , Animales , Antibacterianos/toxicidad , Biodegradación Ambiental , Catálisis , Cloranfenicol/química , Cloranfenicol/toxicidad , Chlorophyta/efectos de los fármacos , Chlorophyta/metabolismo , Daphnia/efectos de los fármacos , Daphnia/metabolismo , Lepidium sativum/efectos de los fármacos , Lepidium sativum/metabolismo , Aguas del Alcantarillado/química , Titanio/química , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Crónica , Contaminantes Químicos del Agua/toxicidad
20.
Ecotoxicol Environ Saf ; 117: 107-14, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25841066

RESUMEN

The large-scale use of titanium dioxide nanoparticles (nano-TiO2) in consumer and industrial applications raised environmental health and safety concerns. Potentially impacted ecosystems include estuarine and coastal organisms. Results from ecotoxicological studies with nano-TiO2 dispersed in salt exposure media are difficult to interpret due to fast flocculation and sedimentation phenomena affecting the dispersion stability. The goal of this study was to investigate the stabilisation effect of alginate on uncoated nano-Ti22 in artificial seawater dispersions used in ecotoxicity bioassays. The most effective stabilisation was obtained at alginate concentration of 0.45 g/L after sonicating dispersions for 20 min (100 W). The size distribution remained constant after re-suspension, indicating that no agglomeration occurred after deposition. Ecotoxicity tests on Artemia franciscana and Phaeodactylum tricornutum did not show any adverse effects related to the presence of alginate in the exposure media, and provided evidence on possible reduced bioavailability of nano-TiO2. The suitable concentration of alginate is recommended to occur on a case-by-case basis.


Asunto(s)
Alginatos/toxicidad , Ecotoxicología/métodos , Nanopartículas/toxicidad , Titanio/toxicidad , Pruebas de Toxicidad/métodos , Alginatos/química , Animales , Artemia , Diatomeas , Ácido Glucurónico/química , Ácido Glucurónico/toxicidad , Ácidos Hexurónicos/química , Ácidos Hexurónicos/toxicidad , Agua de Mar , Suspensiones/química
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