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1.
Sci Total Environ ; 803: 149982, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34487908

RESUMEN

Over recent decades, increasing chemical contamination has greatly affected aquatic life and human health, even though most contaminants are present at low concentrations. The large-scale chemical industrial parks (CIPs) concentrated in the Yangtze River Delta account for over half of the total in China, and Jiangsu Province occupies one fifth of the Yangtze River Delta. Inevitably, the ecosystems could be affected by these CIPs. In this study, we collected 35 water and 12 sediment samples from the Yangtze River (Taizhou section) surrounding waters adjacent to concentrated CIPs and determined their cumulative chemical levels to be 0.2 to 28.4 µg/L and cumulative detections to be 11 to 39 contaminants with a median of 20 contaminants. 61 out of 153 screened chemicals were detected from at least one sampling site, and 6 contaminants, mostly semi-volatile organic compounds, appeared at all sites. Among these detected chemicals, di-n-octyl phthalate and dibutyl phthalate were at the highest levels. Ecological assessment revealed that 4-chloroaniline, phenol and dibutyl phthalate possibly would induce adverse effects on Yangtze River (Taizhou) ecosystems. Further aided with an evaluation of integrated biomarker response (IBR) index, it was found that site W06 (downstream of Binjiang CIP wastewater inlet) was the location in greatest need of urgent action. As a result, the microbial diversity of sediments in the Yangtze River mainstream was significantly higher than that of tributaries, where CIPs wastewater entered.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Químicos del Agua , China , Ecosistema , Sedimentos Geológicos , Humanos , Medición de Riesgo , Ríos , Contaminantes Químicos del Agua/análisis
2.
Environ Pollut ; 292(Pt B): 118398, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34695516

RESUMEN

Despite the ubiquity of per- and polyfluorinated alkyl substances (PFAS) in all environmental compartments, little is known about the pollution they cause on the African continent, neither on levels, nor effects. Here we examined the occurrence and levels of 21 legacy and emerging PFAS in 9 marine species (3 fish, 2 crustaceans and 4 mollusks) collected from Bizerte lagoon, Northern Tunisia. Furthermore, assessment of potential human health risks through consumption of contaminated seafood was examined. This is the first study assessing PFAS in Mediterranean coastal areas of North Africa. Twelve out of the 21 targeted PFAS were detected, evidencing the occurrence of PFAS in seafood from North Africa, albeit at low levels. The Æ©21PFAS concentrations in all seafood samples ranged from 0.202 ng g-1 dry weight (dw) to 2.89 ng g-1 dw, with a mean value of 1.10 ± 0.89 ng g-1 dw. The profiles of PFAS varied significantly among different species, which might be related to their different trophic level, protein content, feeding behaviour and metabolism. Generally, current exposure to PFAS through seafood consumption indicates that it should not be of concern to the local consumers, at least for those PFAS for which information is available.


Asunto(s)
Fluorocarburos , Contaminantes Químicos del Agua , Animales , Ecosistema , Monitoreo del Ambiente , Peces , Fluorocarburos/análisis , Humanos , Alimentos Marinos , Contaminantes Químicos del Agua/análisis
3.
Food Chem ; 371: 131133, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34808758

RESUMEN

Octopus play an increasingly important role in ocean ecosystems and global fisheries, yet techniques for authenticating provenance are sorely lacking. For the first time, we investigate whether chemical profiling can distinguish geographical origins of octopus on international and domestic scales. Our samples consisted of wild-caught octopus from south-east Asia and southern Australia, regions with high seafood trade. We used a novel combination of stable carbon (δ13C) and oxygen (δ18O) isotope analyses (Isotope-Ratio Mass Spectrometry) of internal calcified structures called statoliths, with elemental analyses (X-Ray Fluorescence using Itrax) of soft-tissue. We found that multivariate profiles exhibited distinctive regional signatures, even across species, with high classification success (∼95%) back to region of origin. This study validates isotopic and multi-elemental profiling as an effective provenance tool for octopus, which could be used to support transparency and accountability of seafood supply chains and thus encourage sustainable use of ocean resources.


Asunto(s)
Octopodiformes , Animales , Isótopos de Carbono/análisis , Ecosistema , Espectrometría de Masas , Isótopos de Nitrógeno/análisis , Alimentos Marinos/análisis
4.
Environ Pollut ; 292(Pt B): 118415, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34718087

RESUMEN

The cumulative impact of microplastic and organic enrichment is still largely unknown. Here, we investigated the microplastic contamination, the organic enrichment and their effects on meiofaunal distribution and diversity in two islands of the Maldivian archipelago: one more pristine, and another strongly anthropized. Field studies were coupled with manipulative experiments in which microplastic polymers were added to sediments from the non-anthropized island (i.e., without organic enrichment) to assess the relative effect of microplastic pollution on meiofauna assemblages. Our results reveal that the impact of microplastic contamination on meiofaunal abundance and taxa richness was more significant in the anthropized island, which was also characterized by a significant organic enrichment. Meiofauna exposed experimentally to microplastic contamination showed: i) the increased abundance of opportunistic nematodes and copepods and ii) a shift in the trophic structure, increasing relevance in epistrate-feeder nematodes. Based on all these results, we argue that the coexistence of chronic organic enrichment and microplastics can significantly increase the ecological impacts on meiofaunal assemblages. Since microplastic pollution in the oceans is predicted to increase in the next decades, its negative effects on benthic biodiversity and functioning of tropical ecosystems are expected to worsen especially when coupled with human-induced eutrophication. Urgent actions and management plans are needed to avoid the cumulative impact of microplastic and organic enrichment.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Biodiversidad , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Humanos , Plásticos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
5.
Environ Pollut ; 292(Pt A): 118262, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34601033

RESUMEN

We present a comprehensive review of the sediment quality triad (SQT) assessment studies in Korea. The bibliographic analysis was applied to evaluate how approaches in sediment assessment have evolved. A meta-analysis was performed, to evaluate potential risks of sedimentary persistent toxic substances (PTSs) reported in Korean coastal waters. Within the framework, we identified and discussed current status and spatiotemporal trends in contamination of both classic and emerging PTSs over the recent decadal period. Out of 26 target regions in Korea, five hotspots (Sihwa, Masan, Ulsan, Taean, and Gwangyang) of concern could be identified. Four of those regions have been designated as Specially-Managed Sea Area under the implementation of Total Pollution Load Management System in Korea, except for Taean coast (oil spill site). Meantime, we could identify three stepwise research phases based on a bibliographic analysis; Phase 1 (1995-2008), Phase 2 (2009-2015), and Phase 3 (2016-2020). It is noteworthy that a technical evolution of the SQT assessment by the phase was featured. It was also evidenced that in-depth studies adopting multiple lines of evidence (LOEs) became prevailed upon approaching Phase 3. In a quantitative manner, the toxicity explanatory power of target PTSs increased by about 10% in Phase 3 compared to the earlier phases. The meta-analysis using ratio-to-mean value method applied for the data set having all three LOEs indicated general improvement of sediment qualities in the hotspots. However, their associations quite varied across regions and years, reflecting a dynamicity in oceanographic settings and/or heterogeneity in toxicological effect or benthic community response. At present, SQT assessment adopting the increased LOEs generally supports better assessment. In conclusion, we suggest that future SQT studies globally should reaffirm the utility of the "multiple LOEs approach", focusing on the identification and management of causative toxicants that driving negative ecological impacts on marine ecosystems.


Asunto(s)
Sedimentos Geológicos , Contaminantes Químicos del Agua , Ecosistema , Monitoreo del Ambiente , República de Corea , Contaminantes Químicos del Agua/análisis
6.
Chemosphere ; 287(Pt 3): 132206, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34560496

RESUMEN

The flux of terrestrial dissolved inorganic phosphorous (DIP, i.e. PO43-) via rivers into coastal seas is usually calculated by simply multiplying its concentration with the corresponding water flow at the river mouth. Subsequent adsorption/desorption of DIP onto suspended sediment and the influence of salinity in the estuary are often overlooked. A series of DIP adsorption/desorption experiments under different salinities (0, 5, 15, 30) and suspended sediment concentrations (1-40 g L-1) were conducted in order to assess the potential influence of these factors on the overall DIP loading to the coastal zone. The effect of different sea-salt ions on DIP adsorption/desorption was also assessed by comparing different experimental solutions (NaCl solution, artificial seawater and real seawater). In estuaries, the adsorption of DIP to suspended sediments was greater than desorption, and the net adsorption increased with increasing concentration of suspended sediments and salinity. This enhanced DIP adsorption onto suspended sediment reduces the riverine discharge of DIP to coastal ecosystems. Disregarding this process, especially for the gated estuaries with high sediment resuspension, potentially leads to an overestimation of the terrestrial DIP input to the coastal region.


Asunto(s)
Ríos , Contaminantes Químicos del Agua , Adsorción , Ecosistema , Monitoreo del Ambiente , Estuarios , Sedimentos Geológicos , Fósforo/análisis , Contaminantes Químicos del Agua/análisis
7.
Sci Total Environ ; 805: 150253, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-34818787

RESUMEN

Siverskyi Donets is the fourth longest river in Ukraine and its ecosystem is heavily affected by numerous agricultural and industrial activities. An impact of the on-going armed military conflicts in the Eastern Ukraine to the overall pollution by the chemicals has been studied. Considering the uncontrolled activities in the catchment due to the conflict, there is a high demand to assess the contamination status of the Siverskyi Donets basin. In this study, the occurrence of the EU Water Framework Directive priority substances, selected physicochemical parameters and wide-range emerging contaminants were investigated in surface water, groundwater, biota and river sediments samples from 13 sampling sites in the river basin. The study included metals, inorganic, non-polar and polar organic contaminants. The wide-scope target screening of 2316 substances and suspect screening of 2219 substances revealed occurrence of 83 compounds in the studied samples. A few industrial chemicals such as plasticizers bisphenol A and DEHP, as well as flame retardant brominated diphenylethers were found to be potentially hazardous to the ecosystem, exceeding the established legacy environmental quality standards (EQS) or the provisional no-effect concentration (PNEC) values. River sediment samples contained traces of long-term banned chemicals such as polychlorinated biphenyls (PCBs) and degradation products of DDT (p,p'-DDD and p,p'-DDE). A simplified risk assessment based on comparison of measured concentration of the detected compounds against their (eco)toxicity threshold values from the NORMAN Ecotoxicology Database has been performed to aid their prioritization in future monitoring and, eventually, establishing the list of Siverskyi Donets River Basin Specific Pollutants. A comparison with the recent similar studies in the Dniester and Dnieper river basins in Ukraine has shown that the overall pollution by chemicals in the Siverskyi Donets basin is significantly lower.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Biota , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Ríos , Agua , Contaminantes Químicos del Agua/análisis
8.
Sci Total Environ ; 805: 150403, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-34818812

RESUMEN

The rising temperatures, increased evaporation, and altered precipitation patterns associated with global warming pose threats to aquatic ecosystems, especially the salinization of lake water and changes in the terrestrial carbon budget. We studied a series of samples of catchment soils, surface sediments, and sediment cores from 51 lakes and reservoirs covering an extensive climatic range in northeastern China. Measurements included salinity indices (electrical conductivity and pH) and other physicochemical parameters, including magnetic properties and color (chroma). The results indicate that the occurrence of salt minerals and the salinity of the lake sediments are dominated by the arid climatic conditions of the region. This enabled us to develop climatic transfer functions between salinity, precipitation and evaporation, with potential applications in paleoclimatic research. As carbonates are the dominant salts in most of the studied lakes and reservoirs, past salinity variations are likely reflected by changes in HCO3- and CO32- concentrations, which provides the opportunity to study the response of water-CO2-carbonate interactions to climate change. Our findings emphasize the important role of alkaline lakes in carbon burial and carbon neutralization, in the context of ongoing global warming.


Asunto(s)
Cambio Climático , Lagos , China , Ecosistema , Sedimentos Geológicos , Salinidad
9.
Sci Total Environ ; 804: 150117, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34508938

RESUMEN

Plastic debris into the environment is a growing threat for the ecosystems and human health. The seafood sector is particularly concerned because it generates plastic losses and can be endangered by plastic contamination. Life cycle assessment (LCA) does not properly consider plastic losses and related impacts, which is a problem in order to find relevant mitigation strategies without burden shifting. This work proposes a methodology for quantifying flows of plastics from the life cycle of the seafood products to the environment. It is based on loss rate and final release rate considering a pre-fate approach as proposed by the Plastic Leak Project. They are defined for 5 types of micro and macro plastic losses: lost fishing gears, marine coatings, plastic pellets, tire abrasion and plastic mismanaged at the end-of-life. The methodology is validated with a case study applied to French fish products for which relevant data are available in the Agribalyse 3.0 database. Results show that average plastic losses are from 75 mg to 4345 mg per kg of fish at the consumer, depending on the species and the related fishing method. The main plastic losses come from lost fishing gears (macroplastics) and tire abrasion (microplastics). Results show high variability: when mismanaged, plastic packaging at the end-of-life (macroplastics) is the main loss to the environment. As a next step the methodology is to be applied to other fish or shellfish products, or directly implemented in a life cycle inventory database. Further research should characterize the related impacts to the environment when life cycle impact assessment methodologies will be available, and identify eco-design solutions to decrease the major flows to the environment identified.


Asunto(s)
Plásticos , Contaminantes Químicos del Agua , Animales , Ecosistema , Monitoreo del Ambiente , Productos Pesqueros , Humanos , Estadios del Ciclo de Vida , Alimentos Marinos , Residuos/análisis , Contaminantes Químicos del Agua/análisis
10.
Chemosphere ; 286(Pt 2): 131806, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34426137

RESUMEN

Microplastics, as defined here as plastics with a diameter of <5 mm, can impose severely detrimental impacts on the environment and can now be commonly found in different water bodies. To date, the status of microplastics in limnic systems, which have different hydrologic systems compared to other water bodies such as oceans or rivers, has rarely been reviewed. In the present study, the microplastic pollutants in different countries and regions were comparatively investigated in terms of their abundances, morphologies, and polymer types in the water and sediments of lakes. The concentration and characteristics of microplastics were found to be largely different across countries and regions, which was related to the local development level and economic structure. The migration paths of microplastics in the inner and external limnic ecosystems further revealed the causes for the regional divergence in microplastics. Policy developments in different countries and regions were also discussed to highlight the urgency of better controlling microplastic pollution in lake systems. The characteristics of microplastics vary across countries and regions, depending on the local development level and economic structure.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Lagos , Plásticos , Contaminantes Químicos del Agua/análisis
11.
J Hazard Mater ; 421: 126789, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34365235

RESUMEN

Microbial communities inhabiting soil-water-sediment continuum in coastal areas provide important ecosystem services. Their adaptation in response to environmental stressors, particularly mitigating the impact of pollutants discharged from human activities, has been considered for the development of microbial biomonitoring tools, but their use is still in the infancy. Here, chemical and molecular (16S rRNA gene metabarcoding) approaches were combined in order to determine the impact of pollutants on microbial assemblages inhabiting the aquatic network of a soil-water-sediment continuum around the Ichkeul Lake (Tunisia), an area highly impacted by human activities. Samples were collected within the soil-river-lake continuum at three stations in dry (summer) and wet (winter) seasons. The contaminant pressure index (PI), which integrates Polycyclic aromatic hydrocarbons (PAHs), alkanes, Organochlorine pesticides (OCPs) and metal contents, and the microbial pressure index microgAMBI, based on bacterial community structure, showed significant correlation with contamination level and differences between seasons. The comparison of prokaryotic communities further revealed specific assemblages for soil, river and lake sediments. Correlation analyses identified potential "specialist" genera for the different compartments, whose abundances were correlated with the pollutant type found. Additionally, PICRUSt analysis revealed the metabolic potential for pollutant transformation or degradation of the identified "specialist" species, providing information to estimate the recovery capacity of the ecosystem. Such findings offer the possibility to define a relevant set of microbial indicators for assessing the effects of human activities on aquatic ecosystems. Microbial indicators, including the detection of "specialist" and sensitive taxa, and their functional capacity, might be useful, in combination with integrative microbial indices, to constitute accurate biomonitoring tools for the management and restoration of complex coastal aquatic systems.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Biomarcadores , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Humanos , Lagos , Hidrocarburos Policíclicos Aromáticos/análisis , ARN Ribosómico 16S/genética , Ríos , Suelo , Contaminantes Químicos del Agua/análisis
12.
Chemosphere ; 286(Pt 1): 131677, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34346336

RESUMEN

China is considered to account for nearly a third of all plastic waste discharging from land to the ocean. To overall assess microplastic pollution status in Chinese coastal and marginal seas, this study summarized the abundance and characteristics of microplastics in the seawater, sediments and marine organisms. The results showed that the abundance of microplastics in the seawater of four major seas of China was 0.13-545 items/m³, and microplastic abundance in the sediments from the estuaries was 20-7900 items/kg, which are at middle level or even lower than those detected in other countries. By contrast, severe microplastic pollution was recorded in the estuaries, suggesting that plastic waste and microplastic interception measures should be conducted on the rivers to prevent the input of microplastics. In addition, microplastics were widely detected in marine fishes, mollusks, zooplankton, mammals and birds, which highlights the potential impacts of microplastic pollution on the whole marine ecosystem. Compared to the dry season, higher microplastic abundance was found in the rainy season, revealing that plastic waste recycling should be strengthened before the onset of rainy season. We suggest that all countries respond actively to the ubiquitous microplastic pollution through practical policies and measures to prevent microplastics from further damaging the marine ecosystem.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , China , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Océanos y Mares , Plásticos , Agua de Mar , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
13.
J Hazard Mater ; 421: 126743, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34364212

RESUMEN

Limited knowledge of the combined effects of water and sediment properties and metal ionic characteristics on the solid-liquid partitioning of heavy metals constrains the effective management of urban waterways. This study investigated the synergistic influence of key water, sediment and ionic properties on the adsorption-desorption behavior of weakly-bound heavy metals. Field study results indicated that clay minerals are unlikely to adsorb heavy metals in the weakly-bound fraction of sediments (e.g., r = -0.37, kaolinite vs. Cd), whilst dissociation of metal-phosphates can increase metal solubility (e.g., r = 0.61, dissolved phosphorus vs. Zn). High salinity favors solubility of weakly-bound metals due to cation exchange (e.g., r = 0.60, conductivity vs. Cr). Dissolved organic matter does not favor metal solubility (e.g., r = -0.002, DOC vs. Pb) due to salt-induced flocculation. Laboratory study revealed that water pH and salinity dictate metal partitioning due to ionic properties of Ca2+ and H+. Selectivity for particulate phase increased in the order Cu>Pb>Ni>Zn, generally following the softness (2.89, 3.58, 2.82, 2.34, respectively) of the metal ions. Desorption followed the order Ni>Zn>Pb>Cu, which was attributed to decreased hydrolysis constant (pK1 = 9.4, 9.6, 7.8, 7.5, respectively). The study outcomes provide fundamental knowledge for understanding the mobility and potential ecotoxicological impacts of heavy metals in aquatic ecosystems.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Adsorción , China , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados/análisis , Agua , Contaminantes Químicos del Agua/análisis
14.
Sci Total Environ ; 804: 150116, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34520926

RESUMEN

Influence of land use and population characteristics on solid-liquid partitioning of heavy metals in aquatic ecosystems is little understood. This study hypothesised that the partitioning of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) between water and sediments is influenced by different land use classes, their configuration patterns including patch density, Shannon's diversity index, largest patch index, and splitting index and population density. Relationships between variables were investigated from different distances to the stream network (sub-catchment and riparian scales) and considering land use patterns within individual land use classes and individual sub-catchments as a whole (class and landscape levels, respectively). The study outcomes confirmed that the influence of land use and configuration on metals partitioning is scale independent. However, population density increases metal bioavailability at the riparian scale compared to the sub-catchment scale. Agricultural lands discharge the highest fractions of dissolved metals at both spatial scales (eigenvectors = 0.409 - sub-catchment, and -0.533 - riparian, whilst metals have opposite loadings). Positive relationships between splitting index and metal partitioning confirmed that the division of anthropogenic land uses into smaller patches reduces water pollution. However, high fragmentation of forested areas increases the fraction of soluble metals. Further, high patch density and patch diversity are beneficial for controlling the solubility of some metals. Configuration metrics at the landscape level fundamentally reproduce the patterns of the largest land use type and are not effective for assessing metal partitioning. Therefore, analyses at the class level are preferred. This research investigation contributes essential knowledge to improve land use management strategies and, thereby, help safeguard urban waterways.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , China , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados/análisis , Ríos , Agua , Contaminantes Químicos del Agua/análisis
15.
Environ Monit Assess ; 193(12): 843, 2021 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34837143

RESUMEN

Pacific atolls are extremely vulnerable to the effects of climate change. Coral reef ecosystems, which are responsible for the island formation and maintenance, can potentially keep pace with rising sea levels. Such ecosystems are sensitive to pollution; however, the sources and levels of atoll pollutants caused by urbanization have rarely been investigated. In this study, we assessed the heavy metal pollution (Cr, Mn, Ni, Cu, Zn, Cd, and Pb) of coastal sediments to evaluate the effects of urbanization on Majuro Atoll, the Marshall Islands. The densely populated area had the most significant pollution with high levels of Pb, Mn, Zn, and Cu due to road traffic activity. Domestic wastewater, a major pollution source in Pacific atolls, was not identified. Remarkably, the Zn and Pb levels in the lagoonal coasts of the remote island area were 697 - 1539 and 22 - 337 times higher, respectively, than in the natural area of Funafuti Atoll, Tuvalu. Thus, the remote island and sparsely populated areas were significantly polluted because of the maritime traffic activity in the lagoon and debris accumulation in/around the lagoon. This pollution resulted from improper municipal solid waste management of the main island. The contamination factor, pollution load index, and geo-accumulation index indicated high levels of heavy metal pollution in these areas. Urbanization of the atoll clearly resulted in a distinct heavy metal composition and high pollution levels compared with Funafuti Atoll. These findings emphasize the importance of pollution management in the conservation and rehabilitation of urbanized atolls threatened by future sea-level rises.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , China , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados/análisis , Micronesia , Medición de Riesgo , Aguas Residuales , Contaminantes Químicos del Agua/análisis
16.
Environ Monit Assess ; 193(12): 767, 2021 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-34731306

RESUMEN

The sediment contamination by trace metals in coastal aquatic ecosystems is a worldwide environmental problem, since metals can be toxic, persistent, and bioaccumulated. In case of natural events, such as storms, or anthropogenic activities, like dredging, the sediment resuspension to the water column occurs and can solubilize metals, probably increasing their bioavailability and consequently the risk to aquatic life. This study evaluated the bioavailability on reactive trace metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in estuarine sediments from Iguaçu and Meriti Rivers, both in the drainage basin of Guanabara Bay (Rio de Janeiro, Brazil). Additionally, a discussion about the anthropogenic interference throughout time of six short sediments cores, calculating three different indexes (contamination factors, CF; potential ecological risk index for a single heavy metal, Eif for short; potential ecological risk, PERI) was performed. It was considered as reactive phase, the metal concentrations obtained using a weak acid extraction (in HCl 1 mol L-1 solution). Zn presented high concentrations after resuspension, being above effect range medium (ERM) (52.81 to 1337.4 mg kg-1). The CF indicated very high contamination degree for Cu (14.62 to 17.96) and Zn (27.80 to 35.85) for both rivers. The Eif for short presented higher risk to Cu and Zn for Iguaçu and Meriti rivers. PERI index classified Meriti River samples as severely contaminated (238.10 to 351.62).


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Brasil , China , Ecosistema , Monitoreo del Ambiente , Estuarios , Sedimentos Geológicos , Metales Pesados/análisis , Medición de Riesgo , Ríos , Contaminantes Químicos del Agua/análisis
17.
Environ Monit Assess ; 193(12): 807, 2021 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-34782956

RESUMEN

The purpose of this study is to assess metal concentrations and their bioavailability, and relate them to concentrations in fish tissues (gill, muscle and skin) as part of the ecotoxicological and public health assessment of the St Lucia system. Eight metals from six sites (Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) and five metals (Cu, Fe, Mn, Pb and Zn) from 60 fish, Oreochromis mossambicus, were analysed. Dissolved metal concentrations were highest in the north lake and lowest at the estuary. Sediment metal concentrations were highest in the north lake and lowest in the south lake. Most sediment metals displayed minimal to no anthropogenic enrichment. Normalisation with Fe showed all linear regressions as significant (p < 0.01) and Cr, Cu, Mn, Ni and Zn had R2 values well above 0.9. Only sediment Ni values were above the ERM. Tissue Cu, Fe and Pb concentrations were highest in the gills and Mn and Zn concentrations were highest in the skin. Skin Mn concentrations were highest as compared to the gills and muscle for all sites. The spatial differences in metal concentrations and BCF values for St Lucia suggest distinct populations of fish in the different areas of St Lucia. All concentrations of metals in fish tissues were below the permissible values indicating low human health threat. While higher sediment concentrations justified the economic benefit of mining, evidence of natural enrichment emphasised the need for continual conservation of the greater St Lucia area.


Asunto(s)
Metales Pesados , Tilapia , Contaminantes Químicos del Agua , Animales , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Humanos , Lagos , Metales Pesados/análisis , Salud Pública , Agua , Contaminantes Químicos del Agua/análisis
18.
PLoS One ; 16(10): e0258150, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34618833

RESUMEN

Bigheaded Carp have spread throughout the Mississippi River basin since the 1970s. Little has stopped the spread as carp have the ability to pass through locks and dams, and they are currently approaching the Great Lakes. However, the location of the leading edge in the Illinois River has stalled for over a decade, even though there is no barrier preventing further advancement towards the Great Lakes. Defining why carp are not moving towards the Great Lakes is important for predicting why they might advance in the future. The aim of this study was to test the hypothesis that anthropogenic contaminants in the Illinois River may be playing a role in preventing further upstream movement of Bigheaded Carp. Ninety three livers were collected from carp at several locations between May and October of 2018. Liver samples were analyzed using gas chromatography-mass spectrometry in a targeted metabolite profiling approach. Livers from carp at the leading edge had differences in energy use and metabolism, and suppression of protective mechanisms relative to downstream fish; differences were consistent across time. This body of work provides evidence that water quality is linked to carp movement in the Illinois River. As water quality in this region continues to improve, consideration of this impact on carp spread is essential to protect the Great Lakes.


Asunto(s)
Migración Animal/fisiología , Carpas/metabolismo , Ecosistema , Metabolómica , Animales , Carpas/fisiología , Monitoreo del Ambiente/métodos , Humanos , Illinois , Especies Introducidas , Lagos , Mississippi , Ríos , Alimentos Marinos
19.
Environ Sci Technol ; 55(22): 15466-15475, 2021 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-34698488

RESUMEN

The seagrass ecosystem is among the most efficient natural carbon sinks that can contribute to climate change mitigation. However, little is known about the effects of coastal nutrient enrichment caused by anthropogenic activities and/or climate change on the capacity of the seagrass blue carbon sink. Our experimental manipulations of sediment nutrient enrichment shifted the blue carbon sink capabilities of seagrass meadows. Sediment nutrient enrichment significantly increased the nutrient content of seagrass litter, stimulating the decomposition of rhizome + root litter by ∼10% while retarding the decomposition of leaf litter by ∼5%. Sediment N + P enrichment increased seagrass growth and litter production, while enrichment of N or P alone did not. Organic carbon (Corg) stocks in the surface sediments (0-5 cm) were 34% higher than those in the control with N + P enrichment due to high litter production and the low decomposition rate of nutrient-enriched leaf litter. However, Corg stocks in the subsurface sediments (5-20 cm) did not increase with sediment nutrient enrichment, which is likely due to accelerated decomposition of rhizome + root litter. Our findings suggest that nutrient loading in coastal sediments alters the blue carbon sink and storage capacities in seagrass meadows by changing the rates of carbon sequestration and decomposition.


Asunto(s)
Secuestro de Carbono , Ecosistema , Carbono , Cambio Climático , Sedimentos Geológicos , Nutrientes
20.
Mar Environ Res ; 172: 105499, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34628147

RESUMEN

Discrepancies were found between Ecological Status of sediments evaluated though the analysis of macrobenthic community and chemical analyses along a heavily trafficked and contaminated maritime seaway in Tyrrhenian Sea. Chemical analyses showed some sites highly contaminated by PAHs and metals with values exceeding thresholds for Good Chemical status and representing potential toxicological risk for benthic animals. Conversely, macrobenthic communities were highly rich and diverse, with Ecological Status (through M-AMBI) Good and High at each site. Sampling depth, total organic carbon, and total nitrogen were the major factors influencing biotic indices (AMBI, M-AMBI, S, H), even if concentrations of PAHs and metals (V, As, and Fe) contributed in explaining a part of indices variability. Habitat heterogeneity of sampled sites is likely acting as a confounding factor for two reasons: (1) high variability of environmental parameters leads to high richness and diversity, to which M-AMBI is sensitive, and (2) environmental parameters explained part of the variability of indices, together with contaminants. Our results suggested the importance of considering natural variability as a fundamental step of environmental impact assessment, for the correct interpretation of biotic indices.


Asunto(s)
Contaminantes Ambientales , Invertebrados , Animales , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Metales
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