RESUMEN
Microplastics (MPs) have unique toxicokinetic (TK) processes that differ from those of soluble pollutants. This study investigated the ingestion, migration, accumulation, and clearance of environmental aging MPs in the Japanese swamp shrimp (Macrobrachium nipponense). The concentrations of plastic additives and personal care products adsorbed onto MPs in natural river water were determined, and TK models for MPs and MPs-loaded pollutants were developed. Results showed that the formation of surface biofilms and alterations in the distribution of MPs in waters caused by environmental aging affect MPs bioavailability, which is mainly related to the feeding habits of shrimp. The decrease in MPs particle size caused by biological digestion and the increase in the number of oxygen-containing functional groups caused by environmental aging affect the TK process of MPs. The TK model of MPs-loaded pollutants revealed the cleaning effect of shrimp on pollutants adsorbed onto MPs during swallowing and spitting MPs. This cleaning effect significantly increases the bioavailability of MPs-associated pollutants in aquatic environments. This study provides a new perspective for understanding the interactions between environmental MPs and their associated pollutants in aquatic ecosystems.
Asunto(s)
Disponibilidad Biológica , Microplásticos , Palaemonidae , Contaminantes Químicos del Agua , Animales , Microplásticos/toxicidad , Microplásticos/farmacocinética , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/farmacocinética , Palaemonidae/efectos de los fármacos , Toxicocinética , AdsorciónRESUMEN
Direct ingestion of micro/nanoplastics (MNPs) results in significant accumulation in gastrointestinal (GI) tract of fish. The breathing process of fish makes MNPs easily retained in their gills. However, the uptake of MNPs in other fish organs remains largely unknown, let alone their kinetic processes. Herein, microplastics (MPs) and nanoplastics (NPs) in vivo imaging and precise quantification in various tissues (GI tract, gill, liver, brain, eye, and skin) of seawater (SW)- and freshwater (FW)- acclimated medaka Oryzias melastigma were achieved at an environmentally relevant concentration. Subsequently, the distribution kinetics of MNPs was investigated over a 96-h uptake and 48-h depuration period. MNPs were quickly and mostly captured in GI tract and gill of O. melastigma, and then transferred to liver and brain likely via blood circulation. Such transport was more efficient for NPs as compared to MPs, as evidenced by the consistently higher bioconcentration factors in both SW and FW conditions. The detection of MNPs in eye and skin of O. melastigma was more of an adsorption process, although the specific mechanisms of adsorption and absorption process can hardly be clearly differentiated. This study presented distribution kinetics of MNPs in O. melastigma and highlighted their possible transportation among tissues.
Asunto(s)
Microplásticos , Oryzias , Contaminantes Químicos del Agua , Animales , Microplásticos/toxicidad , Oryzias/metabolismo , Contaminantes Químicos del Agua/farmacocinética , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/análisis , Cinética , Distribución Tisular , Nanopartículas/química , Nanopartículas/toxicidad , Branquias/metabolismo , Piel/metabolismo , Agua de Mar/química , Hígado/metabolismoRESUMEN
Although irregularly-shaped label-free microplastics (MPs) are predominantly distributed in the environment, non-destructive analysis of environmentally relevant MPs in organisms is still challenging. The purpose of the study is to suggest in vivo visual evidence of the uptake and effect of environmentally relevant MPs in organism. Transparent irregularly-shaped high-density polyethylene was selected as an environmentally relevant model MP and exposed to brine shrimp (Artemia franciscana). As a result, we suggest the application of SEM/EDX and coherent anti-Stokes Raman scattering (CARS) microspectroscopy as complementary tools to secure in vivo visual evidence of irregularly-shaped unlabeled MPs in living organisms without chemical digestion for biodistribution observations. Biological transmission electron microscopy also provides how ingested MPs physically affects the digestive tract in the brine shrimp which is rarely reported. In terms of environmental implications, this study would advance ecotoxicological research on microplastic pollution by providing a cutting-edge tool for investigating the bioavailability and ecotoxicity of environmentally relevant MPs in ecosystems.
Asunto(s)
Artemia , Microplásticos , Contaminantes Químicos del Agua , Animales , Microplásticos/toxicidad , Artemia/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/farmacocinética , Polietileno/toxicidad , Polietileno/química , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/metabolismo , Espectrometría Raman , Microscopía Electrónica de TransmisiónRESUMEN
Pharmaceutical uptake involves processes that vary across aquatic systems and biota. However, single studies examining multiple environmental compartments, microhabitats, biota, and exposure pathways in mesoconsumer fish are sparse. We investigated the pharmaceutical burden in bonefish (Albula vulpes), pathways of exposure, and estimated exposure to a human daily dose. To evaluate exposure pathways, the number and composition of pharmaceuticals across compartments and the bioconcentration in prey and bonefish were assessed. To evaluate bioaccumulation, we proposed the use of a field-derived bioaccumulation factor (fBAF), due to variability inherent to natural systems. Exposure to a human daily dose was based on bonefish daily energetic requirements and consumption rates using pharmaceutical concentrations in prey. Pharmaceutical number and concentration were highest in prey, followed by bonefish, water and sediment. Fifteen pharmaceuticals were detected in common among bonefish, prey, and water; all of which bioconcentrated in prey and bonefish, and four bioaccumulated in bonefish. The composition of detected pharmaceuticals was compartment specific, and prey were most similar to bonefish. Bonefish were exposed to a maximum of 1.2 % of a human daily dose via prey consumption. Results highlight the need for multicompartment assessments of exposure and consideration of prey along with water as a pathway of exposure.
Asunto(s)
Contaminantes Químicos del Agua , Animales , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/farmacocinética , Preparaciones Farmacéuticas/metabolismo , Preparaciones Farmacéuticas/análisis , Peces/metabolismo , Bioacumulación , Cadena Alimentaria , Monitoreo del Ambiente , HumanosRESUMEN
The issue of toxic metal pollution is a considerable environmental concern owing to its complex nature, spatial and temporal variability, and susceptibility to environmental factors. Current water quality criteria and ecological risk assessments of metals are based on single-metal toxicity data from short-term, simplified indoor exposure conditions, ignoring the complexity of actual environmental conditions. This results in increased uncertainty in predicting toxic metal toxicity and risk assessment. Using appropriate bioavailability and effect modeling of metals is critical for establishing environmental quality standards and performing risk assessments for metals. Traditional dose-effect models are based on a static statistical relationship and fall short of revealing the bioavailability and effect processes of metals and do not effectively assess ecological impacts under complex exposure conditions. This paper summarizes the toxicokinetic-toxicodynamic (TK-TD) model, which is gaining interest in environmental and ecotoxicological research. The key concepts, and theories of its construction theories, are discussed and the application of the TK-TD model in toxicity prediction and risk assessment of different metals in the aquatic environment, and trends in the development of the TK-TD model are highlighted. The findings of our review prove that the TK-TD model can effectively predict toxic metal toxicity in real time and under complex exposure conditions in the future.
Asunto(s)
Metales , Toxicocinética , Contaminantes Químicos del Agua , Medición de Riesgo , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/farmacocinética , Metales/toxicidad , Metales/farmacocinética , Animales , Organismos Acuáticos/efectos de los fármacos , Modelos Biológicos , Monitoreo del Ambiente/métodosRESUMEN
Though bioaccumulation of pharmaceuticals by aquatic organisms continues to receive scientific attention, the internal disposition of these contaminants among different tissue compartments of fish species has been infrequently investigated, particularly among fish at different trophic positions. We tested a human to fish biological read-across hypothesis for contaminant disposition by examining tissue-specific accumulation in three understudied species, longnose gar (Lepisosteus osseus; piscivore), gizzard shad (Dorosoma cepedianum; planktivore/detritivore), and smallmouth buffalo (Ictiobus bubalus; benthivore), from a river influenced by municipal effluent discharge. In addition to surface water, fish plasma, and brain, gill, gonad, liver, and lateral muscle fillet tissues were analyzed via isotope dilution liquid chromatography tandem mass spectrometry. Caffeine and sucralose, two common effluent tracers, were quantitated at low micrograms per liter levels in surface water, while an anticonvulsant, carbamazepine, was observed at levels up to 37 ng/L. The selective serotonin reuptake inhibitors (SSRIs) fluoxetine and sertraline and primary metabolites were detected in at least one tissue of all three species at low micrograms per kilogram concentrations. Within each species, brain and liver of select fish contained the highest levels of SSRIs compared to plasma and other tissues, which is generally consistent with human tissue disposition patterns. However, we observed differential accumulation among specific tissue types and species. For example, mean levels of sertraline in brain and liver tissues were 13.4 µg/kg and 1.5 µg/kg in gizzard shad and 1.3 µg/kg and 7.3 µg/kg in longnose gar, respectively. In contrast, smallmouth buffalo did not consistently accumulate SSRIs to detectable levels. Tissue-specific eco-exposome efforts are necessary to understand mechanisms associated with such marked bioaccumulation and internal dispositional differences among freshwater fish species occupying different trophic positions. Environ Toxicol Chem 2024;43:1894-1902. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
Asunto(s)
Peces , Contaminantes Químicos del Agua , Animales , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/farmacocinética , Peces/metabolismo , Bioacumulación , Distribución Tisular , Carbamazepina/metabolismo , Carbamazepina/farmacocinética , Sacarosa/metabolismo , Sacarosa/análogos & derivados , Cafeína/metabolismo , Cafeína/farmacocinética , Hígado/metabolismo , Inhibidores Selectivos de la Recaptación de Serotonina/metabolismo , Inhibidores Selectivos de la Recaptación de Serotonina/farmacocinética , Branquias/metabolismo , Monitoreo del Ambiente , Ríos/química , Cadena Alimentaria , Fluoxetina/análogos & derivados , Fluoxetina/metabolismo , Fluoxetina/farmacocinética , Preparaciones Farmacéuticas/metabolismo , Encéfalo/metabolismoRESUMEN
Despite the great interest in the consequences of global change stressors on marine organisms, their interactive effects on cadmium (Cd) bioaccumulation/biotoxicity are very poorly explored, particularly in combination with the toxicokinetic model and molecular mechanism. According to the projections for 2100, this study investigated the impact of elevated pCO2 and increased temperature (isolated or joint) on Cd uptake dynamics and transcriptomic response in the marine copepod Tigriopus japonicus. Toxicokinetic results showed significantly higher Cd uptake in copepods under increased temperature and its combination with elevated pCO2 relative to the ambient condition, linking to enhanced Cd bioaccumulation. Transcriptome analysis revealed that, under increased temperature and its combination with elevated pCO2, up-regulated expression of Cd uptake-related genes but down-regulation of Cd exclusion-related genes might cause increased cellular Cd level, which not only activated detoxification and stress response but also induced oxidative stress and concomitant apoptosis, demonstrating aggravated Cd biotoxicity. However, these were less pronouncedly affected by elevated pCO2 exposure. Therefore, temperature seems to be a primary factor in increasing Cd accumulation and its toxicity in the future ocean. Our findings suggest that we should refocus the interactive effects between climate change stressors and Cd pollution, especially considering temperature as a dominant driver.
Asunto(s)
Cadmio , Copépodos , Contaminantes Químicos del Agua , Cadmio/toxicidad , Cadmio/farmacocinética , Animales , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/farmacocinética , Copépodos/efectos de los fármacos , Copépodos/metabolismo , Copépodos/genética , Dióxido de Carbono/toxicidad , Dióxido de Carbono/metabolismo , Toxicocinética , Transcriptoma/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Cambio Climático , Temperatura , CalorRESUMEN
Uptake and elimination kinetics, bioconcentration factors (BCFs), and metabolic transformation of 20 different pharmaceutically active compounds (PhACs), covering a wide range of therapeutic categories and physico-chemical properties, were studied using zebrafish (Danio rerio). The fish were exposed to the mixture of the selected PhACs at environmentally relevant concentrations similar to 10 µg L-1. The experiments were performed in semi-static conditions and comprised a 7-day uptake period followed by a 7-day depuration period. Most of the PhACs reached a concentration plateau within the 7-day uptake-phase which was followed by an efficient depuration, with the observed uptake (ku) and depuration rate constants (kd,) ranging between 0.002 and 3.752 L kg-1 h-1, and 0.010 to 0.217 h-1, respectively. The investigated PhACs showed low to moderate BCFs. The highest BCFs of 47.8, 28.6 and 47.6 L kg-1 were determined for sertraline, diazepam and desloratadine, respectively. A high contribution of metabolic products to the total internal concentration was observed for some PhACs such as codeine (69%), sulfamethoxazole (51%) and verapamil (87%), which has to be taken into account when assessing the bioconcentration potential. Moreover, most of the metabolites exhibited significantly longer half-lives in zebrafish than their parent compounds and affected the overall depuration kinetics.
Asunto(s)
Contaminantes Químicos del Agua , Pez Cebra , Pez Cebra/metabolismo , Animales , Cinética , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/farmacocinética , Preparaciones Farmacéuticas/metabolismo , Bioacumulación , BiotransformaciónRESUMEN
Amino antioxidants (AAOs), a suite of emerging organic contaminants, have been widely used in numerous industrial and commercial products to inhibit oxidation and corrosion. Recently, their environmental ubiquity, health risks, bioaccumulative and toxic potential have led to mounting public concern. This review summarizes the current state of knowledge on the production and usage, environmental occurrence, bioavailability, human exposure, and aquatic toxicity of representative AAOs, and provides suggestions for future research directions. Previous studies have revealed widespread distribution of many AAOs in various environmental matrixes, including air, water, sediment, dust, and biota. In addition to parent compounds, their degradation products, such as 2-anilino-5-(1,3-dimethylbutylamino)-1,4-benzoquinone (6PPD-Q) and 4-nitrodiphenylamine (4-NO2-DPA), have also been detected at high levels in multiple compartments. Dust ingestion and air inhalation are the two most well-investigated routes for human exposure to AAOs and their transformation products, while studies on other pathways (e.g., skin contact and dietary intake) still remain extremely limited. Moreover, AAO burdens in human tissue have been poorly documented. Toxicological data have shown that a few AAOs may cause teratogenic, developmental, reproductive, endocrinic, neuronic, and genetic toxicity to aquatic organisms, and the toxic capacities of degradation products differ from their precursors. Future studies should focus on elucidating AAO exposure for humans and associated health risks. Additionally, more attention should be given to AAO transformation products (particularly those quinoid derivatives possessing substantial affinity with DNA) and to the effects of complex mixtures of these chemicals.
Asunto(s)
Antioxidantes , Benzoquinonas , Exposición a Riesgos Ambientales , Fenilendiaminas , Contaminantes Químicos del Agua , Humanos , Antioxidantes/análisis , Antioxidantes/farmacocinética , Antioxidantes/toxicidad , Organismos Acuáticos/efectos de los fármacos , Polvo/análisis , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/farmacocinética , Contaminantes Químicos del Agua/toxicidad , Disponibilidad Biológica , Fenilendiaminas/análisis , Fenilendiaminas/farmacocinética , Fenilendiaminas/toxicidad , Benzoquinonas/análisis , Benzoquinonas/farmacocinética , Benzoquinonas/toxicidadRESUMEN
Pyrethroids pesticides (PPs) are the widely adopted synthetic pesticides for agriculture and fishery. The frequent use of these pesticides leads to the accumulation of residues in the freshwater environments in China, subsequently affecting aquatic organisms and ecosystems. However, there are few reports on the toxicological and risk assessment of aquaculture aquatic products. In this study, the uptake, depuration kinetics and potential risk to human health and ecology of fenpropathrin, cypermethrin, fenvalerate, and deltamethrin were assessed using tilapia. The results indicated that four PPs were readily accumulated by tilapia. The bioconcentration factors (BCF) of the PPs in plasma and muscle were between 71.3 and 2112.1 L/kg and 23.9-295.3 L/kg, respectively. The half-lives (t1/2) of muscle and plasma were 2.90-9.20 d and 2.57-8.15 d. The risks of PPs residues in the muscle of tilapia and exposed water were evaluated by hazard quotient (HQ) and risk quotient (RQ). Although PPs residues in tilapia had a low dietary risk to human health, the residues in the exposed water had a high ecological risk to fish, daphnia, and green algae. Therefore, assessing the PPs content in freshwater aquaculture and monitoring their dosages and frequencies are highly necessitated to avoid their adverse effect on the aquaculture environment.
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Plaguicidas , Piretrinas , Tilapia , Contaminantes Químicos del Agua , Animales , Ecosistema , Humanos , Piretrinas/toxicidad , Medición de Riesgo , Toxicocinética , Agua , Contaminantes Químicos del Agua/farmacocinética , Contaminantes Químicos del Agua/toxicidadRESUMEN
Substances such as pharmaceuticals, pesticides, dyes, synthetic and natural hormones, plasticizers, and industrial chemicals enter the environment daily. Many of them are a matter of growing concern worldwide. The use of ultrasound to eliminate these compounds arises as an interesting alternative for treating mineral water, seawater, and urine. Thereby, this work presents a systematic and critical review of the literature on the elimination of organic contaminants in these particular matrices, using ultrasound-based processes. The degradation efficiency of the sonochemical systems, the influence of the nature of the pollutant (volatile, hydrophobic, or hydrophilic character), matrix effects (enhancement or detrimental ability compared to pure water), and the role of the contaminant concentration were considered. The combinations of ultrasound with other degradation processes, to overcome the intrinsic limitations of the sonochemical process, were considered. Also, energy consumptions and energy costs associated with pollutants degradation in the target matrices were estimated. Moreover, the gaps that should be developed in future works, on the sonodegradation of organic contaminants in mineral water, seawater, and urine, were discussed.
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Contaminantes Químicos del Agua/análisis , Contaminantes Ambientales , Aguas Minerales , Agua de Mar , Contaminantes Químicos del Agua/farmacocinéticaRESUMEN
In this study, we investigated the influence of temperature on the bioaccumulation and depuration of Crassostrea gigas exposed to Cd associated with its molecular responses. Oysters were acclimatized to different temperatures (10 °C, 15 °C, 20 °C, 25 °C, and 30 °C) for 14 d and then exposed to 10 µg/L Cd for 28 d, followed by a depuration period of 35 d. Oysters were sampled for chemical analysis by inductively coupled plasma mass spectrometry (ICP-MS) and for mRNA quantification by qPCR. In the digestive gland, gill, and mantle, the cadmium concentration at 10 °C was significantly lower than that at 25 °C and 30 °C in both the whole experiments. The use of a two-compartment model showed that the uptake rate k1 in the above three tissues increased with increasing temperatures ranging from 15 to 25 °C. The fastest elimination rates and shortest half-lives were observed at 15-25 °C. The induction of metallothionein (MT) only occurred in the digestive gland at 15 °C and 20 °C at the end of the accumulation phase. In the mantle and gills, the expression of P-glycoprotein (P-gp) was significantly induced at the end of the accumulation phase and significantly inhibited at the end of the depuration phase. In the digestive gland, the expression of P-gp was induced at the end of both the accumulation and depuration phases. Heat shock protein (hsp70) expression exhibited an overall increasing trend throughout the experiment.
Asunto(s)
Cadmio/farmacocinética , Cadmio/toxicidad , Crassostrea/efectos de los fármacos , Crassostrea/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Animales , Expresión Génica/efectos de los fármacos , Proteínas HSP70 de Choque Térmico/genética , Metalotioneína/genética , Temperatura , Distribución Tisular , Toxicocinética , Contaminantes Químicos del Agua/farmacocinética , Contaminantes Químicos del Agua/toxicidadRESUMEN
This study focuses on the adsorption kinetics of four highly potent sex hormones (estrone (E1), 17ß-estradiol (E2), 17α-ethinylestradiol (EE2), and estriol (E3)), present in water reservoirs, which are considered a major cause of fish feminization, low sperm count in males, breast and ovarian cancer in females induced by hormonal imbalance. Herein, electrospun polymeric nanostructures were produced from cellulose acetate, polyamide, polyethersulfone, polyurethanes (918 and elastollan), and polyacrylonitrile (PAN) to simultaneously adsorbing these estrogenic hormones in a single step process and to compare their performance. These nanofibers possessed an average fiber diameter in the range 174-330 nm and their specific surface area ranged between 10.2 and 20.9 m2g-1. The adsorption-desorption process was investigated in four cycles to determine the effective reusability of the adsorption systems. A one-step high-performance liquid chromatography technique was developed to detect and quantify concurrently each hormone present in the solution. Experimental data were obtained to determine the adsorption kinetics by applying pseudo-first-order, pseudo-second-order and intraparticle diffusion models. Findings showed that E1, E2 and EE2 best fitted pseudo-second-order kinetics, while E3 followed pseudo-first-order kinetics. It was found that polyurethane Elastollan nanofibers had maximum adsorption capacities of 0.801, 0.590, 0.736 and 0.382 mg g-1for E1, E2, EE2 and E3, respectively. In addition, the results revealed that polyurethane Elastollan nanofibers had the highest percentage efficiency of estrogens removal at â¼58.9% due to its strong hydrogen bonding with estrogenic hormones, while the least removal efficiency for PAN at â¼35.1%. Consecutive adsorption-desorption cycles demonstrated that polyurethane maintained the best efficiency, even after being repeatedly used four times compared to the other polymers. Overall, the findings indicate that all the studied nanostructures have the potential to be effective adsorbents for concurrently eradicating such estrogens from the environment.
Asunto(s)
Técnicas Electroquímicas/métodos , Disruptores Endocrinos , Congéneres del Estradiol , Nanofibras/química , Contaminantes Químicos del Agua , Adsorción , Disruptores Endocrinos/química , Disruptores Endocrinos/metabolismo , Disruptores Endocrinos/farmacocinética , Congéneres del Estradiol/química , Congéneres del Estradiol/metabolismo , Congéneres del Estradiol/farmacocinética , Cinética , Membranas Artificiales , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/farmacocinética , Purificación del AguaRESUMEN
The first determination of presence and biodistribution of PFOA in ninety specimens of sea urchin Paracentrotus lividus from two differently contaminated sites along Palermo's coastline (Sicily) is reported. Analyses were performed on the sea urchins' coelomic fluids, coelomocytes, gonads or mixed organs, as well as on seawater and Posidonia oceanica leaves samples from the collection sites. PFOA concentration ranged between 1 and 13 ng/L in seawater and between 0 and 794 ng/g in P. oceanica. The analyses carried out on individuals of P. lividus from the least polluted site (A) showed PFOA median values equal to 0 in all the matrices (coelomic fluid, coelomocytes and gonads). Conversely, individuals collected from the most polluted site (B) showed median PFOA concentrations of 21 ng/g in coelomic fluid, 153 ng/g in coelomocytes, and 195 ng/g in gonads. Calculated bioconcentration factors of log10BCF > 3.7 confirmed the very bioaccumulative nature of PFOA. Significant correlations were found between the PFOA concentration of the coelomic fluid versus the total PFOA concentration of the entire sea urchin. PERMANOVA (p = 0.001) end Welch's t-test (p < 0.001) analyses showed a difference between specimens collected from the two sites highlighting the potential application of P. lividus as sentinel species for PFOA biomonitoring.
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Caprilatos/farmacocinética , Monitoreo del Ambiente/métodos , Fluorocarburos/farmacocinética , Paracentrotus/metabolismo , Animales , Aguas Salinas/química , Agua de Mar/química , Distribución Tisular , Contaminantes Químicos del Agua/farmacocinéticaRESUMEN
It is known that, as the vast majority of the anthropogenically emitted mercury can be found in aquatic ecosystems, where several methylating bacteria are present, fish consumption represents the most critical intake source of the most toxic form of mercury, the methylmercury (MeHg). The aim of this work is to predict MeHg levels in the fish muscles which, being the edible portion, are part of the human diet. A physiologically based toxicokinetics model was developed to evaluate the kinetics of MeHg in red mullets. Fishes were described by means of a multi-compartment model including stomach, gut, blood, muscles and an additional compartment virtually encompassing all the remaining organs. Absorption, distribution and excretion were modelled considering different MeHg routes of administration and excretion: intake by ingestion of contaminated food, intake and elimination through inhalation-exhalation and excretion through feces. The model has been firstly validated on Terapon jarbua fish (using the weighted least squares method for parameter estimation) to be subsequently readapted to predict methylmercury concentrations in the muscle of red mullets (using an approximate Bayesian computation approach). This simple multicompartmental model could be considered part, a link in the chain, of a wider more complex project aiming at tracking the fate of MeHg from polluted seawater to the human end consumer. The present study could be useful to surveillance organizations in order to carry out a more comprehensive and informed risk assessment analysis and to take appropriate preventive measures by evaluating possible new MeHg concentration thresholds to minimize public health hazards.
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Compuestos de Metilmercurio/farmacocinética , Compuestos de Metilmercurio/toxicidad , Smegmamorpha/metabolismo , Contaminantes Químicos del Agua/farmacocinética , Contaminantes Químicos del Agua/toxicidad , Animales , Distribución Tisular/efectos de los fármacos , Distribución Tisular/fisiología , ToxicocinéticaRESUMEN
Aluminum (Al) and manganese (Mn) can be toxic to aquatic biota and cause endocrine disruption in fish, affecting reproduction. This study evaluates the physiological responses of the ray-finned teleost fish Astyanax altiparanae vitellogenic females after acute exposure (96 h) to Al and Mn (alone and combined) in acid pH followed by the same period of exposure to metal-free water in neutral pH. The aim of this second period of exposure was to assess the recovery capacity from the toxic effects these metals. Five experimental groups were established: a control in neutral pH (Ctrl), and acidic pH (Ac), aluminum (Al), manganese (Mn), and Al + Mn groups, maintaining the acidic pH in the groups to which metals were added. The following biological parameters were evaluated: metal tissue concentration, relative fecundity (RF: absolute fecundity/body mass). Plasma levels of cortisol (proxy for stress) and 17α hydroxyprogesterone (17α-OHP), and gene expression of pituitary lhß mRNA (proxies for final maturation) were measured to evaluate endocrine disruption. In the synchronic exposure, the presence of Mn potentiated the accumulation of Al in gills. The females from acidic pH and Al groups showed a reduced RF. Exposure to Al and Mn triggered an endocrine disruption response, evidenced by a decrease in the plasma concentration of 17α-OHP and cortisol. Despite this anti-steroidogenic effect, no changes occurred in the pituitary gene expression of lhß. The endocrine changes and the metal accumulation were temporary, while the impacts on RF under the experimental conditions suggest permanent impairment in the reproduction of this species.
Asunto(s)
Aluminio/toxicidad , Characidae , Disruptores Endocrinos/toxicidad , Manganeso/toxicidad , Ovario/efectos de los fármacos , 17-alfa-Hidroxiprogesterona/sangre , Aluminio/farmacocinética , Animales , Characidae/fisiología , Ecotoxicología , Disruptores Endocrinos/farmacocinética , Femenino , Fertilidad/efectos de los fármacos , Proteínas de Peces/genética , Hidrocortisona/sangre , Concentración de Iones de Hidrógeno , Manganeso/farmacocinética , Distribución Tisular , Agua/química , Contaminantes Químicos del Agua/farmacocinética , Contaminantes Químicos del Agua/toxicidadRESUMEN
Metallothionein (MT) plays an important role in protecting organisms from the adverse effects of Cd, Hg, Zn and Cu. Investigations on mammals show variations in metallothionein concentrations and inducibility with age. This has never been investigated in invertebrates, and we determined the concentrations and inducibility of metallothionein in gills and midgut gland of different size classes of shore crabs from uncontaminated areas. Metallothionein concentrations in gills and midgut gland ranged between 30 and 40 µg g-1 dry weight with no differences among the different size classes. Concentrations of cadmium, copper and zinc in the midgut gland increased with increasing size of the crabs when the concentrations were expressed on a dry weight basis; water content in the midgut gland increased with the size and only the cadmium concentration increased with size when concentrations were expressed on wet weight basis. There was an inverse relationship between metallothionein and both copper and cadmium concentrations. Smaller crabs exposed to 1 mg Cd L-1 accumulated higher concentrations of cadmium in midgut gland and gills than larger ones and metallothionein concentrations in the midgut gland were higher in the smaller crabs. However, the increase in metallothionein concentration per accumulated unit of cadmium showed a linear increase with the size of the crabs. The ratio [Cd]midgut/[Cd]gills decreased with the size of the crabs. The overall conclusion is that baseline metallothionein concentrations do not change with age in shore crabs, but that the inducibility of metallothionein upon cadmium challenge does.
Asunto(s)
Braquiuros/efectos de los fármacos , Braquiuros/fisiología , Cadmio/toxicidad , Metalotioneína/metabolismo , Animales , Tamaño Corporal , Braquiuros/anatomía & histología , Cadmio/análisis , Cadmio/farmacocinética , Cobre/análisis , Ecotoxicología/métodos , Branquias/efectos de los fármacos , Branquias/metabolismo , Distribución Tisular , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/farmacocinética , Contaminantes Químicos del Agua/toxicidad , Zinc/análisisRESUMEN
Coexistence of metals and microplastics (MPs) in aquatic environments represents a growing concern; however, little is known regarding the risks associated with their combined effects. Here, the effects of five metals (As, Cd, Cu, Pb, and Zn), alone or combined with MPs for various premixing durations (30 and 60 days), on the juvenile and adult stages of the marine mysid Neomysis awatschensis were evaluated. The toxicity (50% lethal concentration for 96 h) and bioconcentration of metals premixed with MPs were measured, and their effects on the antioxidant defense and cholinergic systems were examined. Metal toxicity increased with increasing premixing period with MPs, and juveniles were more sensitive to exposure to metals premixed with MPs than adults. Metal bioconcentration in the mysid body increased following co-exposure with MPs. Metals premixed with MPs significantly increased intracellular malondialdehyde content at both stages but decreased glutathione content in juveniles. At both stages, catalase and superoxide dismutase activity was suppressed following co-exposure to metals and MPs, except under the Cu treatment. Moreover, co-exposure inhibited acetylcholinesterase activity at both stages, suggesting cholinergic impairment. Taken together, metals and MPs produce synergistic detrimental effects on marine mysids in a stage-specific manner. Further studies are warranted to elucidate the role of MPs as a vector for contaminants and stimulator of toxicity in aquatic organisms.
Asunto(s)
Crustáceos/efectos de los fármacos , Metales/farmacocinética , Metales/toxicidad , Microplásticos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Acetilcolinesterasa/metabolismo , Animales , Antioxidantes/metabolismo , Proteínas de Artrópodos/metabolismo , Crustáceos/metabolismo , Ecotoxicología , Biomarcadores Ambientales , Enzimas/metabolismo , Glutatión/metabolismo , Dosificación Letal Mediana , Malondialdehído/metabolismo , Metales/administración & dosificación , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Pruebas de Toxicidad Aguda , Contaminantes Químicos del Agua/farmacocinéticaRESUMEN
Global warming has driven a loss of dissolved oxygen in the ocean in recent decades. We demonstrate the potential for an additional anthropogenic driver of deoxygenation, in which zooplankton consumption of microplastic reduces the grazing on primary producers. In regions where primary production is not limited by macronutrient availability, the reduction of grazing pressure on primary producers causes export production to increase. Consequently, organic particle remineralisation in these regions increases. Employing a comprehensive Earth system model of intermediate complexity, we estimate this additional remineralisation could decrease water column oxygen inventory by as much as 10% in the North Pacific and accelerate global oxygen inventory loss by an extra 0.2-0.5% relative to 1960 values by the year 2020. Although significant uncertainty accompanies these estimates, the potential for physical pollution to have a globally significant biogeochemical signal that exacerbates the consequences of climate warming is a novel feedback not yet considered in climate research.
Asunto(s)
Calentamiento Global , Microplásticos/toxicidad , Modelos Biológicos , Oxígeno/análisis , Agua de Mar/análisis , Contaminantes Químicos del Agua/toxicidad , Zooplancton/efectos de los fármacos , Zooplancton/fisiología , Animales , Simulación por Computador , Ecosistema , Microplásticos/farmacocinética , Océanos y Mares , Contaminantes Químicos del Agua/farmacocinéticaRESUMEN
The multixenobiotic resistance mechanism (MXR) can decrease intracellular genotoxic pressure through the efflux of compounds out of the cell. Thus, this work presents a temporal approach to evaluate the MXR activity and the occurrence of genotoxic damage in different organs of the fish Prochilodus lineatus after an intraperitoneal injection of benzo[a]pyrene (B[a]P). Although the liver and brain demonstrated rapid MXR induction (6 h), the occurrence of DNA damage was not prevented. However, these organs presented some return to DNA integrity after MXR activity. The kidney demonstrated the slowest response in the MXR induction (24 h), which may be related to the preferential excretion of B[a]P metabolites by this route. Moreover, the kidney MXR reduction at 96 h may be related to its role in the excretion of metabolites from all other metabolizing organs. The gills did not appear to play an essential role in xenobiotics efflux; however, their participation in biotransformation is exhibited through the occurrence of DNA damage. The integrated response of the organs in the dynamics for the maintenance of the organism integrity could be promoted by the circulation of the xenobiotic through the bloodstream, which corroborates the increase in the DNA damage in the erythrocytes at 6 h. Therefore, the ability to induce MXR was linked to the preservation of DNA integrity in the presence of B[a]P, since MXR acts to avoid the accumulation of xenobiotics inside the cell.