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1.
Environ Sci Pollut Res Int ; 29(32): 48926-48936, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35199273

RESUMEN

Cigarette butts (CBs) are non-biodegradable residues of synthetic origin, prevalent on beaches all over the world. The study evaluates discarded CBs on an intensely used urban beach, determining variations in physical and chemical characteristics. CBs collected were observed, classified, and visually separated according to a proposed scale of four levels of degradation to test the potential match between physical and chemical decay. CBs (un-smoked, smoked, and discarded) were used to determine the average length (cm) and mass (g) in order to observe changes in these parameters among the levels. Cigarette butts experience consecutive mass loss during environmental exposure. Scanning electron microscopy (SEM) images were obtained to assess physical changes in fibers due to smoking. FTIR-ATR was used to assess CBs new (un-smoked), smoked, and discarded samples in relation to cellulose acetate decay. The FTIR-ATR spectroscopy of the most visually degraded cigarette butts indicated modifications in the spectra when compared to un-smoked cigarettes.


Asunto(s)
Productos de Tabaco , Exposición a Riesgos Ambientales , Monitoreo del Ambiente , Humo/análisis , Fumar , Nicotiana
2.
Mar Pollut Bull ; 166: 112212, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33690085

RESUMEN

Fernando de Noronha Archipelago is highly vulnerable to microplastic pollution, which has been previously reported with snapshot samplings on the site. The present study has performed daily beach sediment samplings on the archipelago, aiming to assess the distribution, characteristics and short-term variability of microplastics (1-5 mm), expressing concentrations in three different units. The concentrations ranged from 0.6 ± 2.5 particles/m2 to 1059.3 ± 1385.6 particles/m2 and showed a large spatial and temporal small-scale variability. The results indicate that microplastic contamination is recurrent in Fernando de Noronha and the distribution of these particles is associated with a combination of various physical processes. A wider comparison with results obtained in beaches worldwide was possible using different units of concentration, but standard methods for sampling and analysis of microplastics is needed to better understanding of large-scale spatial and temporal variability.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Brasil , Monitoreo del Ambiente , Plásticos , Contaminantes Químicos del Agua/análisis
3.
Mar Pollut Bull ; 163: 111978, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33465634

RESUMEN

Seasonal distribution of Marine Litter (ML) on Santos beaches was assessed using a citizen science strategy. Plastics and cigarette butts (CB) were the dominant items in all sampling campaigns. Seasonal distribution did not result in significant differences for most items. Plastic and CB amounts were high in summer compared to autumn. For all sampled sites the presence of beach users influenced ML densities. However, results showed that some sites presented an additional influence of local hydrodynamic. Moderate amounts of hazardous items including metal, glass, CB, sanitary waste and plastic tubes used to pack and market illicit drugs represented between 20.8 and 31% of all ML over the seasons. The beaches of Santos were classified as dirty in autumn and spring and as extremely dirty in winter and summer. These findings can serve as a baseline to support mitigating actions by public authorities and start monitoring programs of ML not only in Santos but also in other urbanized beaches.


Asunto(s)
Playas , Residuos , Brasil , Monitoreo del Ambiente , Plásticos , Residuos/análisis
4.
MethodsX ; 7: 100861, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32300545

RESUMEN

The aim was to describe a methodology developed to study the relationship among the spatio-temporal patterns of habitat utilization, feeding ecology and microplastics (MPs) contamination across the different ontogenetic phases of fishes belonging to different trophic levels and living along the riverine-estuarine-coastal food web. The Goiana Estuary's water column was examined for the seasonal and spatial variation of MPs and their quantification relative to zooplankton, demersal fish species contamination following the same sampling design. The density of MPs in the water column determines their bioavailability. Interest in studies on MPs distribution in relation to spatial and temporal variation of environmental factors and fauna are increasing in quantity and quality. If the ecological strategies presented in this study were replicated in other estuary, comparisons could be made in order to describe how ecosystems work. Standard protocols for sampling, extraction, enumeration and classification of MPs and others pollutant ingested by fishes have been developed and are presented here to encourage comparisons. Standardized and comparable sampling designs and laboratory procedures are an important strategy in order to devise and transfer managerial solutions among different sites and comparisons along time when studying the same environment.

5.
Sci Rep ; 9(1): 13514, 2019 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-31534161

RESUMEN

The dynamics of microfilament (<5 mm) ingestion were evaluated in three species of snooks. The ingestion of different colours and sizes of microfilaments were strongly associated with the spatio-temporal estuarine use and ontogenetic shifts of snooks. Their feeding ecology was also analysed to assess dietary relationships with patterns of contamination. All species were highly contaminated with microfilaments. The highest ingestion of microfilaments occurred in the adults, when fishes became the main prey item and also during the peak of fishing activities, in the rainy season. This suggests that trophic transfer, in addition to periods of high availability of microfilaments are important pathways for contamination. The ingestion of microfilaments of different colours and sizes was likely influenced by input sources. Blue microfilaments were frequently ingested, and appear to have both riverine and estuarine inputs, since they were ingested in all seasons and habitats. Purple and red microfilaments were more frequently ingested in the lower estuarine habitats. The length of microfilaments was also associated with environmental variability. Longer microfilaments were ingested in habitats with greater riverine influence, the opposite was observed for shorter microfilaments. Therefore, microfilament contamination in snooks are a consequence of their ecological patterns of estuarine uses through different seasons and life history stages.


Asunto(s)
Ingestión de Alimentos/fisiología , Perciformes/metabolismo , Contaminantes del Agua/análisis , Animales , Ecosistema , Monitoreo del Ambiente/métodos , Estuarios , Conducta Alimentaria/fisiología , Explotaciones Pesqueras , Peces/metabolismo , Salinidad , Contaminantes Químicos del Agua/análisis
6.
Artículo en Inglés | MEDLINE | ID: mdl-31357681

RESUMEN

Smoking is a social phenomenon of global scope. The impacts start from the cultivation of the plant to the disposal of cigarette butts in the most diverse places. These aspects go beyond economic and public health issues, also affecting natural environments and their biota in a serious and indistinct way. Of the six trillion cigarettes consumed globally each year, four and a half trillion are disposed somewhere in the environment. Cigarette butts are predominantly plastic, non-biodegradable waste, prevalent in coastal environments in various parts of the world, and with high potential for generating impacts on a wide range of socioeconomic and environmental aspects. Among the 5000 compounds found in a cigarette, those with higher toxic potential are mainly concentrated in the filter and in tobacco remnants, which are items found in discarded cigarette butts. After surveying published studies on this topic, the present study addressed the interaction between the impacts related to tobacco smoking, highlighting the problem as an important and emerging issue that demands joint efforts, and actions especially focused on the reduction of environmental impacts, an aspect that has not yet been assessed.


Asunto(s)
Ambiente , Contaminación Ambiental , Productos de Tabaco , Fumar Tabaco , Humanos , Fumar , Nicotiana
7.
Mar Pollut Bull ; 141: 569-572, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30955769

RESUMEN

The strandline is one of the first deposition habitats of microplastics before they are integrated to the beach as a standing stock or finally removed. Beaches, entirely or partially protected by beachrocks, have different sediment dynamics and therefore may present variation in microplastic deposition. The aim of this work was to test if protected and unprotected (i.e., exposed to waves) areas of a sandy beach present different microplastic accumulation on the strandline - a habitat greatly influenced by both water and sediment dynamics. Microplastic (MP) amounts were significantly higher at the protected area (Mprotected = 642.6 ±â€¯514.8 MP m-2, Mexposed = 130.6 ±â€¯126.8 MP m-2, Mann-Whitney U test, U = 14.5, p = 0.0009), showing that beachrocks influence microplastic accumulation on the beach face. Therefore, hard structures parallel to the beach may also affect microplastics deposition on beach sediments, being important to consider these structures on microplastic surveys.


Asunto(s)
Playas , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Brasil , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos
8.
Environ Res ; 172: 137-149, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30782533

RESUMEN

Beach anthropogenic litter is a worldwide problem and has been discussed in the specialized literature for decades. Cigarette butts (CB) are the most frequent form of personal item found on beaches. Yearly, 6 trillion cigarettes are smoked worldwide, and 4.5 trillion cigarettes are littered in the environment. The objective of our review was to assess the relevant literature on the issue of CB in costal environments, including urban areas. We compile and discuss studies (1998-2018) of CB sources for coastal environments, composition/degradability, quantification on beaches, toxicity to aquatic organisms and existing strategies to abate the problem. The literature shows that despite the growing interest in marine litter, this specific issue remains little studied and information is limited in time and space. Studies have been undertaken on islands, continental coasts, estuaries and coastal cities. There area wide variety of approaches to classification; for example, CB are considered plastic in 19% of studies and placed in an isolated category in another 16%. It was possible to identify the main sources of CB in coastal environments and access to the marine biota. In conclusion, we list and discuss proposals for reducing smoking, littering and marine pollution as a contribution to reduce the problems caused by CB in coastal and marine environments. CAPSULE: Cigarette butts are a pervasive, toxic and recalcitrant type of marine litter that requires urgent attention from manufacturers, users, authorities and the public to prevent the ingestion of cigarette butts by biota and water pollution from its leachate.


Asunto(s)
Monitoreo del Ambiente , Productos de Tabaco , Animales , Organismos Acuáticos/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Humanos , Productos de Tabaco/estadística & datos numéricos , Productos de Tabaco/toxicidad , Residuos/estadística & datos numéricos
9.
Sci Total Environ ; 651(Pt 1): 1199-1218, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30360252

RESUMEN

Estuarine pollution imposes rapid, increasing and lasting environmental modifications. In the present review, especial attention is given to estuaries in South America (SA), where legislation, policies and actions to guarantee environmental quality remain ineffective. There, the majority of estuaries face uncontrolled occupation of its margins by urban and industrial centres, agriculture and aquaculture expansion, water extraction and flow control. The lack of basic sanitation and poor environmental management (including territories within Marine Protected Areas) often lead to hydrological alterations, high nutrient loads, and the presence and dynamics of pollutants (nutrient loads, persistent organic pollutants (POPs), metals and plastic debris) along the entire estuarine ecocline. Organic enrichment has increased dissolved oxygen consumption, with wide spatio-temporal variability along latitudes and estuarine gradients. The toxicity, biogeochemistry and availability of metals and POPs depend on the annual fluctuations of salinity, water renewal, dissolved oxygen levels, suspended particulate loads, sediment mobility, grain size and composition at the sink. Plastic debris from land sources are widespread in estuaries, where they continue to fragment into microplastics. River basins are the main contributors of plastics to estuaries, whose transportation and accumulation are subjected to interannual water flow variations. Although some systems seems to be in a better condition in relation to others around the world (e.g. Goiana and Negro estuaries), many others are among the most modified worldwide (e.g. Guanabara Bay and Estero Salado System). We propose that, estuarine conservation plans should consider year-round fluctuations of the ecocline and the resulting cycles of retention and flush of environmental signals and their influence on trophic webs over the whole extent of estuarine gradients.


Asunto(s)
Monitoreo del Ambiente , Estuarios , Contaminantes Químicos del Agua/análisis , Eutrofización , Metales/análisis , Plásticos/análisis , América del Sur
10.
Environ Pollut ; 238: 103-110, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29550607

RESUMEN

Marine plastic pollution is present in all oceans, including remote oceanic islands. Despite the increasing number of articles on plastic pollution in the last years, there is still a lack of studies in islands, that are biodiversity hotspots when compared to the surrounding ocean, and even other recognized highly biodiverse marine environments. Articles published in the peer reviewed literature (N = 20) were analysed according to the presence of macro (>5 mm) and microplastics (<5 mm) on beaches and the marine habitats immediately adjacent to 31 islands of the Atlantic Ocean and Caribbean Sea. The first articles date from the 1980s, but most were published in the 2000s. Articles on macroplastics were predominant in this review (N = 12). Beaches were the most studied environment, possibly due to easy access. The main focus of most articles was the spatial distribution of plastics associated with variables such as position of the beach in relation to wind and currents. Very few studies have analysed plastics colonization by organisms or the identification of persistent organic pollutants (POPs). Islands of the North/South Atlantic and Caribbean Sea were influenced by different sources of macroplastics, being marine-based sources (i.e., fishing activities) predominant in the Atlantic Ocean basin. On the other hand, in the Caribbean Sea, land-based sources were more common.


Asunto(s)
Monitoreo del Ambiente , Plásticos/análisis , Residuos/análisis , Contaminantes del Agua/análisis , Océano Atlántico , Región del Caribe , Ecosistema , Contaminación Ambiental , Islas , Océanos y Mares , Indias Occidentales
11.
PeerJ ; 6: e4332, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29507822

RESUMEN

Spatial and temporal density and biomass of the infaunal mollusk Anomalocardia flexuosa (Linnaeus, 1767) evaluated a tidal plain at Goiana estuary (Northeast Brazil). Three hundred and sixty core samples were taken during an annual cycle from three intertidal habitats (A, B and C). Shell ranged from 2.20 to 28.48 mm (15.08 ± 4.08 mm). Recruitment occurred more intensely from January to March. Total (0-1,129 g m-2) differed seasons (rainy and dry), with highest values in the early rainy season (221.0 ± 231.44 g m-2); and lowest values in the late dry season (57.34 ± 97 g m-2). The lowest occurred during the late rainy (319 ± 259 ind m-2) and early dry (496 ± 607 ind m-2) seasons. Extreme environmental situations (e.g., river flow, salinity and water temperature) at the end of each season also affected density ranges (late dry: 0-5,798 ind m-2; late rainy: 0-1,170 ind m-2). A. flexuosa in the Goiana estuary presented a dominance of juvenile individuals (shell length < 20 mm), with high biomass main the recruitment period. Average shell length, density and biomass values suggest overfishing of the stock unit. A. flexuosa is an important food and income resource along its whole distribution range. The species was previously also known as Anomalocardia brasiliana (Gmelin, 1791).

12.
Environ Pollut ; 236: 706-717, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29453186

RESUMEN

Microplastic contamination was investigated in the gut contents of an economically important estuarine top predator, Cynoscion acoupa, according to spatiotemporal and ontogenetic use of a tropical estuary. Microplastic contamination was found in more than half of the analysed fish. Ingested microplastics were classified by type, colour and length with most of the particles consisting of filaments (<5 mm). Longer filaments were more frequently ingested in the upper estuary and smaller filaments in the lower estuary, as a result of differences in hydrodynamic forces and proximity to the probable input sources. The river is likely an important source of filaments to the estuary and filaments ingested in the upper estuary showed little sign of weathering, when compared with those from the lower estuary, which are subject to intense weathering and consequent break-up of particles to smaller sizes. Most filaments, of all colours, accumulated in adults of C. acoupa, which are more susceptible to contamination through both direct ingestion and trophic transference as they shift their feeding mode to piscivory. Moreover, the highest ingestion of filaments in adults occurred in the lower estuary, during the late rainy season, likely associated with the intense fishing activities in this habitat, which results in a greater input of filaments from fishing gear, which are mainly blue in colour. Overall, 44% of the ingested filaments were blue, 20% purple, 13% black, 10% red and 12% white. The next most common colour, the purple filaments, are most likely blue filaments whose colour has weathered to purple. Red filaments were proportionally more ingested in the lower estuary, indicating a coastal/oceanic source. White and black filaments were more commonly ingested in the inner estuary, suggesting that they have a riverine origin and/or were actively ingested by juveniles and sub-adults, which inhabit the inner estuary and have zooplankton as an important food resource.


Asunto(s)
Explotaciones Pesqueras/estadística & datos numéricos , Perciformes/metabolismo , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Océano Atlántico , Ingestión de Alimentos , Ecosistema , Monitoreo del Ambiente/métodos , Estuarios , Plásticos/metabolismo , Lluvia , Ríos , Estaciones del Año , Contaminantes Químicos del Agua/metabolismo , Zooplancton
13.
Environ Sci Process Impacts ; 17(11): 1868-79, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26457869

RESUMEN

Microplastic pollution is a global issue. It is present even in remote and pristine coastal and marine environments, likely causing impacts of unknown scale. Microplastics are primary- and secondary-sourced plastics with diameters of 5 mm or less that are either free in the water column or mixed in sandy and muddy sediments. Since the early 1970s, they have been reported to pollute marine environments; recently, concern has increased as soaring amounts of microplastics in the oceans were detected and because the development of unprecedented processes involving this pollutant at sea is being unveiled. Coastal and marine environments of the western tropical and sub-tropical Atlantic Ocean (WTAO) are contaminated with microplastics at different quantities and from a variety of types. The main environmental compartments (water, sediments and biota) are contaminated, but the consequences are still poorly understood. Rivers and all scales of fishery activities are identified as the most likely sources of this pollutant to coastal waters; however, based on the types of microplastics observed, other maritime operations are also possible sources. Ingestion by marine biota occurs in the vertebrate groups (fish, birds, and turtles) in these environments. In addition, the presence of microplastics in plankton samples from different habitats of estuaries and oceanic islands is confirmed. The connectivity among environmental compartments regarding microplastic pollution is a new research frontier in the region.


Asunto(s)
Monitoreo del Ambiente , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Océano Atlántico , Biota , Ecosistema , Plancton , Agua de Mar/química , Contaminación Química del Agua/estadística & datos numéricos
14.
Environ Pollut ; 185: 352-64, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24275078

RESUMEN

Recently, research examining the occurrence of microplastics in the marine environment has substantially increased. Field and laboratory work regularly provide new evidence on the fate of microplastic debris. This debris has been observed within every marine habitat. In this study, at least 101 peer-reviewed papers investigating microplastic pollution were critically analysed (Supplementary material). Microplastics are commonly studied in relation to (1) plankton samples, (2) sandy and muddy sediments, (3) vertebrate and invertebrate ingestion, and (4) chemical pollutant interactions. All of the marine organism groups are at an eminent risk of interacting with microplastics according to the available literature. Dozens of works on other relevant issues (i.e., polymer decay at sea, new sampling and laboratory methods, emerging sources, externalities) were also analysed and discussed. This paper provides the first in-depth exploration of the effects of microplastics on the marine environment and biota. The number of scientific publications will increase in response to present and projected plastic uses and discard patterns. Therefore, new themes and important approaches for future work are proposed.


Asunto(s)
Monitoreo del Ambiente , Plásticos/análisis , Residuos/análisis , Contaminantes Químicos del Agua/análisis , Organismos Acuáticos , Biota , Ecosistema , Océanos y Mares , Residuos/estadística & datos numéricos , Contaminación Química del Agua/estadística & datos numéricos
15.
Mar Pollut Bull ; 78(1-2): 252-7, 2014 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24321881

RESUMEN

An experiment observed the behavior of selected tagged plastic items deliberately released in different habitats of a tropical mangrove forest in NE Brazil in late rainy (September) and late dry (March) seasons. Significant differences were not reported among seasons. However, marine debris retention varied among habitats, according to characteristics such as hydrodynamic (i.e., flow rates and volume transported) and relative vegetation (Rhizophora mangle) height and density. The highest grounds retained significantly more items when compared to the borders of the river and the tidal creek. Among the used tagged items, PET bottles were more observed and margarine tubs were less observed, being easily transported to adjacent habitats. Plastic bags were the items most retained near the releasing site. The balance between items retained and items lost was positive, demonstrating that mangrove forests tend to retain plastic marine debris for long periods (months-years).


Asunto(s)
Monitoreo del Ambiente , Plásticos/análisis , Rhizophoraceae , Residuos/análisis , Contaminantes del Agua/análisis , Humedales , Brasil , Clima Tropical , Residuos/estadística & datos numéricos , Contaminación del Agua/estadística & datos numéricos
16.
Mar Pollut Bull ; 75(1-2): 305-309, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-23953893

RESUMEN

Plastic marine debris is presently widely recognised as an important environmental pollutant. Such debris is reported in every habitat of the oceans, from urban tourist beaches to remote islands and from the ocean surface to submarine canyons, and is found buried and deposited on sandy and cobble beaches. Plastic marine debris varies from micrometres to several metres in length and is potentially ingested by animals of every level of the marine food web. Here, we show that synthetic polymers are present in subsurface plankton samples around Saint Peter and Saint Paul Archipelago in the Equatorial Atlantic Ocean. To explain the distribution of microplastics around the Archipelago, we proposed a generalised linear model (GLM) that suggests the existence of an outward gradient of mean plastic-particle densities. Plastic items can be autochthonous or transported over large oceanic distances. One probable source is the small but persistent fishing fleet using the area.


Asunto(s)
Plásticos/análisis , Residuos/análisis , Contaminantes Químicos del Agua/análisis , Océano Atlántico , Ecosistema , Monitoreo del Ambiente , Cadena Alimentaria , Plancton , Contaminación Química del Agua/estadística & datos numéricos
17.
Trans R Soc Trop Med Hyg ; 107(5): 301-6, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23479361

RESUMEN

BACKGROUND: Glucose-6-phosphate dehydrogenase deficiency (G6PDd) has been shown to protect against malaria infection and severe manifestations in African and Asia, but there is a scarcity of studies in the Americas. This study aimed to study the prevalence of G6PDd and its association with malaria occurrence in the Brazilian Amazon. METHODS: A cross-sectional study was conducted in the male population to estimate the prevalence of G6PDd and malaria infection. G6PD deficient samples were genotyped to identify the deficient variant. Number of previous malaria episodes and need for blood transfusion during malaria episodes were recorded by applying a standardized questionary. RESULTS: From a sample of 1478 male individuals, 66 were detected as G6PD deficient, resulting in a prevalence of of 4.5% (95% CI = 3.44-5.56%). Fifty six G6PD deficient individuals (3.8%; 95% CI = 2.82-4.77) presented the G6PD A-variant mutation, while 10 individuals (0.7%; 95% CI = 0.42-0.97) severely deficient were genotyped as carriers of the G6PD Mediterranean variant. After adjusting for age, G6PD deficient individuals were less likely to report the occurrence of malaria episodes, and the protective effect was related to the enzyme activity, with carriers of the GG6PD A-variant presenting a 88% reduction (AOR: 0.119; 95% CI = 0.057-0.252; p < 0.001) and carriers of the Meditarrenean variant presenting 99% lower risk (AOR: 0.010; 95% CI = 0.002-0.252; p < 0.001) when compared to non-deficient individuals. On the other hand, G6PD deficient subjects reported higher need of transfusion during malaria episodes (p < 0.001). CONCLUSION: G6PD enzyme activity was directly related to susceptibility to malaria in the Brazilian Amazon, where P. vivax predominates. Severe G6PDd was associated with considerable higher risk of malaria-related transfusions.


Asunto(s)
Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Malaria/epidemiología , Malaria/genética , Adolescente , Adulto , Anciano , Brasil/epidemiología , Niño , Preescolar , Estudios Transversales , Susceptibilidad a Enfermedades , Variación Genética , Deficiencia de Glucosafosfato Deshidrogenasa/complicaciones , Humanos , Lactante , América Latina/epidemiología , Malaria/complicaciones , Masculino , Persona de Mediana Edad , Prevalencia , Primaquina , Adulto Joven
18.
Environ Res ; 119: 88-100, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22901765

RESUMEN

Anthropogenic activities influence the biogeochemical cycles of mercury, both qualitatively and quantitatively, on a global scale from sources to sinks. Anthropogenic processes that alter the temporal and spatial patterns of sources and cycling processes are changing the impacts of mercury contamination on aquatic biota and humans. Human exposure to mercury is dominated by the consumption of fish and products from aquaculture operations. The risk to society and to ecosystems from mercury contamination is growing, and it is important to monitor these expanding risks. However, the extent and manner to which anthropogenic activities will alter mercury sources and biogeochemical cycling in tropical and sub-tropical coastal environments is poorly understood. Factors as (1) lack of reliable local/regional data; (2) rapidly changing environmental conditions; (3) governmental priorities and; (4) technical actions from supra-national institutions, are some of the obstacles to overcome in mercury cycling research and policy formulation. In the tropics and sub-tropics, research on mercury in the environment is moving from an exploratory "inventory" phase towards more process-oriented studies. Addressing biodiversity conservation and human health issues related to mercury contamination of river basins and tropical coastal environments are an integral part of paragraph 221 of the United Nations document "The Future We Want" issued in Rio de Janeiro in June 2012.


Asunto(s)
Ecosistema , Mercurio/química , Agua de Mar/química , Clima Tropical , Contaminantes Químicos del Agua/química , Animales , Bacterias/metabolismo , Exposición a Riesgos Ambientales , Monitoreo del Ambiente , Humanos , Mercurio/metabolismo , Microbiología del Agua , Contaminantes Químicos del Agua/metabolismo
19.
Mar Pollut Bull ; 62(5): 1098-102, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21354578

RESUMEN

Plastic marine debris is a pervasive type of pollution. River basins and estuaries are a source of plastics pollution for coastal waters and oceans. Estuarine fauna is therefore exposed to chronic plastic pollution. Three important catfish species [Cathorops spixii (N=60), Cathorops agassizii (N=60) and Sciades herzbergii (N=62)] from South Western Atlantic estuaries were investigated in a tropical estuary of the Brazilian Northeast in relation to their accidental ingestion of plastic marine debris. Individuals from all three species had ingested plastics. In C. spixii and C. agassizii, 18% and 33% of individuals had plastic debris in their stomachs, respectively. S. herzbergii showed 18% of individuals were contaminated. All ontogenetic phases (juveniles, sub-adults and adults) were contaminated. Nylon fragments from cables used in fishery activities (subsistence, artisanal and commercial) played a major role in this contamination. These catfish spend their entire life cycles within the estuary and are an important feeding resource for larger, economically important, species. It is not yet possible to quantify the scale and depth of the consequences of this type of pollution. However, plastics are well known threat to living resources in this and other estuaries. Conservation actions will need to from now onto take plastics pollution into consideration.


Asunto(s)
Bagres , Explotaciones Pesqueras , Contenido Digestivo/química , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Monitoreo del Ambiente , Alimentos Marinos/análisis , Contaminación Química del Agua/estadística & datos numéricos
20.
Neotrop. ichthyol ; 9(1): 183-190, Mar. 2011. ilus, tab
Artículo en Inglés | LILACS | ID: lil-583974

RESUMEN

O estuário do rio Goiana (7º30’S 34º47’W) é um típico estuário de região tropical semi-árida. Esse estuário abriga uma fauna rica de peixes, crustáceos e moluscos que tem um importante papel na vida da população tradicional. Ele também é o principal receptor de efluentes da agroindústria da cana-de-açúcar e esgoto das comunidades e vilas. Trichiurus lepturus (n = 104), do estuário do rio Goiana foram examinados para o conteúdo de mercúrio total durante dez meses (2005 a 2007) ao longo de duas estações secas e parte de uma estação chuvosa. Os indivíduos estudados apresentaram peso (P) (204,1±97,9 g) e comprimento total (CT) (63,1±10,1 cm, variação 29,5-89,0 cm) com uma correlação significativa (p<0,05). As correlações entre CT e Hg-T (r = 0,37286) e entre P e Hg-T (r = 0,38212) foram positivas e significativas. A ANOVA (2 fatores) (n = 81) mostrou que o CT e P apresentaram diferenças significativas (p<0,05) entre as estações. O Hg-T apresentou diferença em relação ao fator estação (p<0,05). A correlação entre Hg-T e a chuva apresentou uma relação negativa e significativa (r = -0,56; p<0,05). A precipitação pluviométrica influenciou fortemente a bioacumulação de mercúrio nessa espécie. Os meses secos apresentaram relativamente concentrações de mercúrio maiores do que o final da estação chuvosa. Isso sugere que a menor precipitação pluviométrica, e consequentemente a menor quantidade de material particulado e menor produtividade primária no estuário, torna o mercúrio mais biodisponível. Peixes desse estuário podem ser consumidos pela população humana ao longo de todo ano.


The Goiana River Estuary (7º30’S 34º47’W) is a typical estuary of the semi-arid tropical regions. This estuary shelters a rich fauna of fish, crustaceans and mollusks which play an important role in the life of traditional populations. It is also the main recipient of the effluents from the sugarcane agro-industry and sewage from settlements and villages. Trichiurus lepturus (n = 104), from the Goiana Estuary were examined for total mercury contents during ten months (2005 to 2007) spaning two dry seasons and part of a rainy season. The studied individuals showed weight (W) (204.1±97.9 g) and total length (TL) (63.1±10.1 cm, range 29.5-89.0 cm) with a significant (p<0.05) correlation. Correlation between TL and Hg-T (r = 0.37286) and between W and Hg-T (r = 0.38212) were positive and significant (p<0.05). Two-way ANOVA (n = 81) showed that TL and W had significant difference (p<0.05) among seasons. The Hg-T showed differences in relation to the factor season (p<0.05). The correlation between Hg-T and rainfall showed a negative and significant relation (r = -0.56; p<0.05). Rainfall strongly influenced the bioacumulation of mercury in this species. Dryer months showed relatively higher mercury concentrations than the end of the rainy season. Less rainfall, and consequently less particulate matter and less primary production in the estuary, make mercury more bioavailable. Fish from this estuary are fit for human consumption at all times of the year.


Asunto(s)
Animales , Estuarios/análisis , Mercurio , Fauna Acuática/estadística & datos numéricos , Estaciones del Año
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