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1.
Environ Monit Assess ; 192(10): 628, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32902735

RESUMO

To provide more precise understanding of water quality changes, continuous sampling is being used more in surface water quality monitoring networks. However, it remains unclear how much improvement continuous monitoring provides over spot sampling, in identifying water quality changes over time. This study aims (1) to assess our ability to detect trends using water quality data of both high and low frequencies and (2) to assess the value of using high-frequency data as a surrogate to help detect trends in other constituents. Statistical regression models were used to identify temporal trends and then to assess the trend detection power of high-frequency (15 min) and low-frequency (monthly) data for turbidity and electrical conductivity (EC) data collected across Victoria, Australia. In addition, we developed surrogate models to simulate five sediment and nutrients constituents from runoff, turbidity and EC. A simulation-based statistical approach was then used to the compare the power to detect trends between the low- and high-frequency water quality records. Results show that high-frequency sampling shows clear benefits in trend detection power for turbidity, EC, as well as simulated sediment and nutrients, especially over short data periods. For detecting a 1% annual trend with 5 years of data, up to 97% and 94% improvements on the trend detection probability are offered by high-frequency data compared with monthly data, for turbidity and EC, respectively. Our results highlight the benefits of upgrading monitoring networks with wider application of high-frequency sampling.


Assuntos
Poluentes da Água/análise , Qualidade da Água , Monitoramento Ambiental , Vitória , Água
2.
Bull Environ Contam Toxicol ; 105(4): 522-529, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32955596

RESUMO

Microplastics are persistent, synthetic polymers that have managed to spread even to the most remote places on earth. Studies reporting on the abundance of microplastics have recently increased worldwide, which has raised environmental concerns among scientific communities. Nevertheless, evidence of microplastic contamination from Turkey is limited even though the location is a critical point and the population is higher than most countries in the region. Thus, we aimed to detect microplastics in sediment samples collected from the Marmara Sea in Istanbul-Turkey. In this study, fourteen sediment samples were collected and sub-sampled, then plastic debris was extracted, quantified and characterized by the morphology and polymer structure. The result revealed that all of the samples contained microplastics, and their concentrations ranged between 0.3 and 85.6 g/kg sediment, and the most abundant plastic types were acrylonitrile butadiene styrene, ethylene vinyl acetate, and polystyrene.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Microplásticos/análise , Poluentes da Água/análise , Água do Mar , Turquia
3.
Mar Pollut Bull ; 160: 111600, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32871434

RESUMO

A simplified particle-tracking model with an idealised coastline was used to investigate how the interaction between variable winds and water level (VaWWL) operates spatially along a coast. The model included a constant along-coast current, horizontal diffusion, onshore/offshore wind drift, beach/cliff combinations and point/distributed litter sources. The default model reproduced basic properties of observed beach litter loadings (zero net accumulation, negatively skewed loading distributions) and the observed spatial pattern along the Scottish east coast, with average loadings increasing in the coastal current direction. The VaWWL effect moved the along-coast flux of floating litter offshore as debeaching events occur during offshore winds. Varying diffusion, coastal current speed, windage, beach/cliff combinations and different foreshore boundary conditions were investigated. Reconciling model predictions with previous estimates of plastic inflow suggested sinking rates of up to 90% soon after first entry into the sea. The VaWWL effect offers a realistic boundary condition for particle-tracking models.


Assuntos
Resíduos , Poluentes da Água , Praias , Monitoramento Ambiental , Plásticos/análise , Resíduos/análise , Poluentes da Água/análise , Vento
4.
Ecol Lett ; 23(10): 1479-1487, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32790233

RESUMO

Quantifying sublethal effects of plastics ingestion on marine wildlife is difficult, but key to understanding the ontogeny and population dynamics of affected species. We developed a method that overcomes the difficulties by modelling individual ontogeny under reduced energy intake and expenditure caused by debris ingestion. The predicted ontogeny is combined with a population dynamics model to identify ecological breakpoints: cessation of reproduction or negative population growth. Exemplifying this approach on loggerhead turtles, we find that between 3% and 25% of plastics in digestive contents causes a 2.5-20% reduction in perceived food abundance and total available energy, resulting in a 10-15% lower condition index and 10% to 88% lower total seasonal reproductive output compared to unaffected turtles. The reported plastics ingestion is insufficient to impede sexual maturation, but population declines are possible. The method is readily applicable to other species impacted by debris ingestion.


Assuntos
Tartarugas , Poluentes da Água/análise , Animais , Animais Selvagens , Monitoramento Ambiental , Plásticos , Dinâmica Populacional
5.
Environ Health Prev Med ; 25(1): 29, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32664857

RESUMO

Plastics are extensively used in our daily life. However, a significant amount of plastic waste is discharged to the environment directly or via improper reuse or recycling. Degradation of plastic waste generates micro- or nano-sized plastic particles that are defined as micro- or nanoplastics (MNPs). Microplastics (MPs) are plastic particles with a diameter less than 5 mm, while nanoplastics (NPs) range in diameter from 1 to 100 or 1000 nm. In the current review, we first briefly summarized the environmental contamination of MNPs and then discussed their health impacts based on existing MNP research. Our review indicates that MNPs can be detected in both marine and terrestrial ecosystems worldwide and be ingested and accumulated by animals along the food chain. Evidence has suggested the harmful health impacts of MNPs on marine and freshwater animals. Recent studies found MPs in human stool samples, suggesting that humans are exposed to MPs through food and/or drinking water. However, the effect of MNPs on human health is scarcely researched. In addition to the MNPs themselves, these tiny plastic particles can release plastic additives and/or adsorb other environmental chemicals, many of which have been shown to exhibit endocrine disrupting and other toxic effects. In summary, we conclude that more studies are necessary to provide a comprehensive understanding of MNP pollution hazards and also provide a basis for the subsequent pollution management and control.


Assuntos
Exposição Ambiental , Microplásticos/efeitos adversos , Poluentes da Água/efeitos adversos , Monitoramento Ambiental , Microplásticos/análise , Poluentes da Água/análise
6.
PLoS One ; 15(7): e0236007, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32668449

RESUMO

Leptospirosis is a re-emerging zoonotic disease of high medical importance that affects humans worldwide. Humans or animals acquire an infection with pathogenic leptospires either by direct contact with infected animals or by indirect contact to contaminated environment. Survival of Leptospira spp. in the environment after having been shed via animal urine is thus a key factor to estimate the risk of infection, but not much is known about the tenacity of pathogenic leptospires. Here, the survival time of both a laboratory strain and a field strain of L. kirschneri serovar Grippotyphosa in animal urine and their tenacity while drying was investigated and compared at different temperatures (15°C-37°C). Leptospira spp. are also often found in rivers and ponds. As the infection risk for humans and animals also depends on the spreading and survival of Leptospira spp. in these environments, the survival of L. kirschneri serovar Grippotyphosa was investigated using a 50-meter-long hose system simulating a water stream. Both strains did not survive in undiluted cattle or dog urine. Comparing different temperatures and dilution media, the laboratory strain survived the longest in diluted cattle urine with a slightly alkaline pH value (3 days), whilst the field strain survived in diluted dog urine with a slightly acid pH value up to a maximum of 24 h. Both strains did not survive drying on a solid surface. In a water stream, leptospires were able to move faster or slower than the average velocity of the water due to their intrinsic mobility but were not able to survive the mechanical damage caused by running water in the hose system. From our results we conclude, that once excreted via animal urine, the leptospires immediately need moisture or a water body to survive and stay infectious.


Assuntos
Doenças do Cão/epidemiologia , Leptospira/crescimento & desenvolvimento , Leptospira/isolamento & purificação , Leptospirose/veterinária , Urina/microbiologia , Poluentes da Água/análise , Zoonoses/epidemiologia , Animais , Bovinos , Doenças do Cão/microbiologia , Cães , Feminino , Leptospirose/microbiologia , Doenças Transmitidas pela Água/epidemiologia , Doenças Transmitidas pela Água/microbiologia , Zoonoses/microbiologia
7.
Ecotoxicol Environ Saf ; 201: 110855, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540620

RESUMO

Total dissolved gas (TDG) supersaturation generated by discharged flood water may cause the death of fish downstream of dams and severely threaten their survival during the flood season. No study has performed to investigate the effects of TDG on fish dwelling in shallows in China. Furthermore, varied TDG levels are caused by the varied flow of flood water during the spill season. Fish may alternatingly experience intermittent TDG exposure from equilibrated water and TDG-supersaturated water. However, little research on the effects of intermittent TDG exposure on fish has been conducted. To evaluate the tolerance of fish to continuous acute TDG exposure, juvenile yellow catfish living in the shallows were exposed to TDG-supersaturated water at 125%, 130%, 135% and 140% TDG for 96 h. The results showed that the juvenile yellow catfish exhibited obvious gas bubble disease (GBD) and abnormal behaviours (e.g., exophthalmos and bubbles on fins). The survival probability declined with the arising TDG levels. The median survival time (ST50) of yellow catfish was 8.57, 18.1, 33.86 and 58.84 h at above TDG levels, respectively. To further investigate the effects of intermittent TDG exposure on juvenile yellow catfish, the fish were subjected to varied TDG levels (125%, 130%, 135% and 140%) for a specific duration (3 h and 6 h) and then underwent a period of recovery (3, 6 and 9 h) in equilibrated water. The results showed that an increase in recovery time (or decreasing exposure time) can prolong the survival time of yellow catfish and improve their survival probability at the same exposure time (or same recovery time). Compared with that under continuous acute exposure, the ST50 of juvenile yellow catfish increased significantly with intermittent exposure. Intermittent exposure can enhance the tolerance of juvenile yellow catfish to TDG. The application of the results may contribute to the protection of aquatic organisms and the formulation of the scheme of reservoir operation in the Yangtze River.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Peixes-Gato/fisiologia , Gases/toxicidade , Rios/química , Poluentes da Água/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , China , Gases/análise , Probabilidade , Análise de Sobrevida , Movimentos da Água , Poluentes da Água/análise , Qualidade da Água
8.
Artigo em Inglês | MEDLINE | ID: mdl-32486395

RESUMO

This study was conducted to develop and validate a more reliable total organic carbon (TOC) analytical procedure for water samples containing suspended solids (SS). The effects of the combined ultrasonic and alkaline pretreatment (CULA) on the TOC measurement were studied in water samples containing SS from three origins (algae, sewage particles, and soil) under different analytical conditions (SS concentration, oxidation methods, and sieve size). The applicability of turbidity as a homogeneity index was also evaluated. With CULA, TOC recovery remained high (> 80%) for SS concentration ranges up to four times larger than ultrasonic pretreatment alone (UL) due to enhanced particulate organic carbon (POC) solubilization, and did not significantly differ depending on the oxidation methods, at low SS concentrations, or with varying sieve sizes. In particular, the turbidity change rate (i.e., NTU5/NTU0) of the pretreated water sample showed a high correlation with TOC precision (r2 = 0.73, p < 0.01), which suggests that turbidity can be used as an indicator of sample homogeneity. A novel TOC analytical procedure is expected to be useful for more accurate assessments of the impact of particulate pollutants on water quality than current methods, and for the analysis of the carbon cycle, including POCs, in the environment.


Assuntos
Carbono , Esgotos , Poluentes da Água , Carbono/análise , Ciclo do Carbono , Ultrassom , Poluentes da Água/análise
9.
J Environ Public Health ; 2020: 1347836, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508934

RESUMO

Development of adsorptive stripping voltammetry (AdSV) combined with in situ prepared bismuth film electrode (in situ BiFE) on glassy carbon disk surface using diethylenetriamine pentaacetic acid (DTPA) as a complexing agent and NO3 - as a catalyst to determine the trace amount of chromium (VI) is demonstrated. According to this method, in the preconcentration step at E dep = -800 mV, the bismuth film is coated on the surface of glassy carbon electrodes simultaneously with the adsorption of complexes Cr(III)-DTPA. In addition to the influencing factors, the stripping voltammetry performance factors such as deposition potential, deposition time, equilibration time, cleaning potential, cleaning time, and technical parameters of differential pulse and square wave voltammetries have been investigated, and the influence of Cr(III), Co(II), Ni(II), Ca(II), Fe(III), SO4 2-, Cl-, and Triton X has also been investigated. This method gained good repeatability with RSD <4% (n = 9) for the differential pulse adsorptive stripping voltammetry (DP-AdSV) and RSD < 3% (n = 7) for the square wave adsorptive stripping voltammetry (SqW-AdSV), and low limit of detection: LOD = 12.10-9 M ≈ 0.6 ppb (at a deposition potential (E dep) of -800 mV and the deposition time (t dep) of 50 s) and LOD = 2.10-9 M ≈ 0.1 ppb (at E dep = -800 mV and t dep = 160 s) for the DP-AdSV and SqW-AdSV, respectively. This method has been successfully applied to analyze chromium in natural water.


Assuntos
Bismuto/química , Cromo/análise , Poluentes da Água/análise , Adsorção , Catálise , Cromo/química , Eletroquímica , Eletrodos , Limite de Detecção , Nitratos/química , Ácido Pentético/química , Poluentes da Água/química
10.
Environ Monit Assess ; 192(6): 331, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32377885

RESUMO

The environmental disasters that occurred due to the leakage of mining waste in Mariana-MG (2015) and Brumadinho-MG (2019), located in Brazil, attracted the attention of the scientific community. This designated efforts to investigate the environmental consequences of toxic waste in the affected ecosystem. Therefore, a simple, easily executed and accessible method was presented for arsenic speciation [As(III), As(V), and DMA]. Using an atomic absorption spectrometer coupled to the hydride generation system, the heterogeneous photocatalysis was applied in the reduction of As(V) and DMA to As(III). After the optimization, a calibration curve was constructed, with LODs equivalent to 3.20 µg L-1 As(III), 3.86 µg L-1 As(V), and 6.68 µg L-1 DMA. When applying the method for quantification in environmental samples, a concentration of up to 103.1 ± 9.4 µg L-1 As(V) was determined for surface water samples. The soil samples, 84.1 ± 3.6 µg L-1 As(III) and 112.4 ± 9.9 µg L-1 As(V) were quantified, proving the contamination of the ecosystems impacted by the environmental disasters. We proceeded the study through an addition/recovery method with samples of water, soil, and sediments (collected from impacted environments). Recovery values were equivalent to 99.0% for As(III), 93.8% for As(V), and 99.2% for DMA. Graphical abstract Photocatalytic reduction mechanism of As(V) and DMA to As(III) by heterogeneous photocatalysis.


Assuntos
Arsênico , Nanopartículas , Poluentes do Solo , Poluentes da Água/análise , Óxido de Zinco , Brasil , Ecossistema , Monitoramento Ambiental , Solo , Poluentes do Solo/análise
11.
Chemosphere ; 255: 126833, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32387724

RESUMO

Understanding the transformation pattern of nitrogen (N) pollutants and its pathways in the prechlorinated raw water distribution system (PRWDS) is vital for controlling the stablitiy and safety of raw water qulity. This study investigated the N transformation, N functional genes and their correlations to find the N transformation pathways along the PRWDS. Results suggested that simultaneous nitrification, anaerobic ammonium oxidation and denitrification (SNAD) contribute to the N transformationin the PRWDS. Along the pipeline, anammox 16S rRNA (9.18 × 107-8.41 × 108 copies/g), limited by prechlorination, was the most abundant N functional genes and anammox process was the main pathway of ammonia nitrogen (NH4+-N). The decreasing NH4+-N was connected with Planctomycetes, Nitrospira and abundance of nxrA attributing to the joint effort of anammox and declined nitrification. The concentration of nitrate (NO3--N) increasing at first and then decreasing, was correlated positively with Sphingomonas. because of the declined nitritication and increased denitrification. Besides, the NO3--N→NO2--N process was considered to be primary NO3--N transformation pathways. Increases in the concentration of dissolved organic nitrogen (DON) and nitrite (NO2--N) observed in the PRWDS had positive correlation with relative abundance of Pseudomonas. We believe that prechlorination shaped the particular bacterialcharacteristics in biofilms and influenced the N transformation pathways indirectly, resulting in the varying N transformation rules in PRWDSs. Moreover, systematic and extended research is particularly vital for determining the effects of changes in source water quality and environmental conditions on bacterial community structure and N conversion along PRWDSs.


Assuntos
Nitrogênio/análise , Poluentes da Água/análise , Abastecimento de Água/estatística & dados numéricos , Amônia/metabolismo , Bactérias/metabolismo , Biofilmes , Reatores Biológicos/microbiologia , Desnitrificação , Poluentes Ambientais/metabolismo , Nitratos/metabolismo , Nitrificação , Nitritos/análise , Oxirredução , RNA Ribossômico 16S/metabolismo
12.
Chemosphere ; 252: 126590, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32443271

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are widely distributed in various environmental media and have thus attracted extensive attention worldwide. To prevent and control PAH pollution in China, the study of ambient water quality criteria (AWQC), human health risks, and aquatic ecological risk is critical. There are no reports to date on the human health AWQC of PAHs in China. Therefore, this study first derived the human health AWQC values of 12 PAHs based on exposure data and bioaccumulation factor in China. We found that local exposure parameters and other relevant factors were key during the development of AWQC in different countries and regions, which led to differences with the reference value recommended by USEPA. Based on the incremental life time cancer risk (ILCR), hazard quotients (HQ) and potentially affected fraction (PAF) methods, the health and ecological risks of 16 PAHs were assessed subsequently. And the results are as follows: the non-carcinogenic PAHs' health risks ranged from 1.01 × 10-10 to 1.60 × 10-9, and carcinogenic PAH health risks ranged from 5.03 × 10-7 to 4.74 × 10-5. The toxic effects of 8 PAHs on aquatic organisms exhibited the following order: benzo (a) pyrene (BaP) > anthracene (Ant) > pyrene (Pye) > phenanthrene (Phe) > fluoranthene (Flua) > acenaphthene (Ace) > fluorene (Flu) > naphthalene (Nap). Among these, the ecological risks posed by Ant and BaP were the highest, according to the HQ and PAF methods.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes da Água/análise , Poluição Química da Água/estatística & dados numéricos , Benzo(a)pireno , Carcinógenos/análise , China , Fluorenos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Fenantrenos , Pirenos , Medição de Risco , Qualidade da Água
13.
Mar Pollut Bull ; 154: 111067, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32319900

RESUMO

The individual concentrations and sources of sterols in sediments samples collected in two periods 2017 (dry period /March and rainy period/August) were determined along with the Sergipe-Poxim estuarine system, Aracaju, Brazil. The individual sterols concentration ranged from 135 to 21,746 ng g-1 (March) and 191 to 144,748 ng g-1 (August) and the distribution was mainly dominated by ß-sitosterol in both periods with 37.2% (March) and 70.8% (August) of the total sterols found. In all the sampling sites, the coprostanol levels were higher than 100 ng g1 (March) and 500 ng g-1 (August), indicating sewage contamination. Diagnostic ratios between sterols suggested the predominance of sewage sources. Pearson correlation assessed a correlation significant (March) and negligible (August) between coprostanol concentration levels and organic matter. The principal component analysis (PCA) showed that the sterols levels influenced strongly C1, as well as C2 distinguished between the plant sterols and from sewage.


Assuntos
Monitoramento Ambiental , Poluentes da Água/análise , Brasil , Colestanol , Fezes , Sedimentos Geológicos , Esgotos , Esteróis
14.
Mar Pollut Bull ; 153: 110964, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32275525

RESUMO

The distribution and accumulation of floating marine debris in the Black Sea during the last few decades are analysed by the help of numerical modelling. An approach based on a mesoscale circulation model combined with a particle tracking model is applied. It is established that the litter distribution is nearly independent of the source location and is mainly controlled by the basin circulation system. The western gyre predominantly accumulates floating debris in summer. After the integration of the main cyclonic current in winter, the debris in the inner basin moves east. Retention zones along the south-western coast persist in time. The mean particle stranding time is estimated at about 200 days. Accumulation zones along the south-eastern and eastern coast are abundant in summer, and then move further northeast and north. Simulations demonstrate an increasing litter accumulation in summer on the North Western Shelf and shelf break.


Assuntos
Monitoramento Ambiental , Resíduos , Poluentes da Água/análise , Mar Negro , Plásticos , Estações do Ano
15.
Mar Pollut Bull ; 153: 110967, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32275527

RESUMO

In order to understand the origin of plastic debris pollutants that accumulate in the Canary Islands coastline, six beaches of Gran Canaria Island were studied during different seasons to estimate the abundance and the types of two microplastics fraction sizes (0.01-1 mm and 1-5 mm) and mesoplastics fraction (5-25 mm). For the larger fraction of microplastics and mesoplastics, a high percentage of fragments and foams were found; moreover, both fractions show the same accumulation pattern in relation with the wave, wind, and current. The debris was checked for exogenous and local origins. Moreover, for the smaller fraction of microplastics, only natural, semi-synthetic, and synthetic fibres were found, showing a totally different spatial distribution from the others fractions. This result suggests a possible endogenous origin of the contamination, in relation to the type and amount of wastewater discharges and beach users.


Assuntos
Praias , Monitoramento Ambiental , Plásticos , Poluentes da Água/análise , Ilhas , Espanha
16.
Mar Pollut Bull ; 153: 110983, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32275538

RESUMO

Salt marshes in urban watersheds are prone to microplastics (MP) pollution due to their hydrological characteristics and exposure to urban runoff, but little is known about MP distributions in species from these habitats. In the current study, MP occurrence was determined in six benthic invertebrate species from salt marshes along the North Adriatic lagoons (Italy) and the Schelde estuary (Netherlands). The species represented different feeding modes and sediment localisation. 96% of the analysed specimens (330) did not contain any MP, which was consistent across different regions and sites. Suspension and facultative deposit-feeding bivalves exhibited a lower MP occurrence (0.5-3%) relative to omnivores (95%) but contained a much more variable distribution of MP sizes, shapes and polymers. The study provides indications that MP physicochemical properties and species' ecological traits could all influence MP exposure, uptake and retention in benthic organisms inhabiting European salt marsh ecosystems.


Assuntos
Monitoramento Ambiental/métodos , Microplásticos , Plásticos , Poluentes da Água/análise , Áreas Alagadas , Animais , Ecossistema , Hábitos , Itália , Países Baixos
17.
Environ Res ; 186: 109556, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32334175

RESUMO

Marine litter affects marine organisms, posing threats to biodiversity conservation and to ecosystem structure and functioning. Providing a suitable assessment of marine litter effects on marine life through bioindicator species is crucial to drive an effective waste management policy. However, to date no standardized tool has been developed to describe and monitor the impact of marine macro-litter on marine life within deep-water habitats. Modifying the protocol proposed to monitor macro-litter ingestion by the loggerhead sea turtle Caretta caretta, we perform a preliminary investigation on the suitability of different elasmobranch species for monitoring macro-litter ingestion in deep-sea. A total of 122 specimens representing 7 elasmobranch species were collected and examined. External visual inspections documented no clear evidences of disease due to marine litter entanglement. A total of 7 ingested litter items were found in the stomach or in the esophagus of 6 specimens of 4 different species (frequency of occurrence = 4.9%), with a maximum number of 2 items per specimen. No litter items were found in the intestinal contents, as well as no evidence of gastrointestinal blockages due to litter items were detected. The low number of collected litter items suggests that the number of samples required is too large for a feasible monitoring program. Moreover, we observed that the anatomy of the intestinal spiral valve may represent an obstacle to the transit of macro-litter items, which could be spontaneously regurgitated as it happens in the selective elimination of undigested remains, such as bones and scales. Therefore, macro-litter retention time in the gastrointestinal tract of elasmobranchs could be brief and shorter than retention time of food. This may lead to an underestimation of macro-litter ingestion frequency by deep-water elasmobranchs. This study reports the first evidence of plastic ingestion by the kitefin shark Dalatias licha.


Assuntos
Ecossistema , Poluentes da Água , Animais , Monitoramento Ambiental , Mar Mediterrâneo , Plásticos , Resíduos/análise , Água , Poluentes da Água/análise
18.
Environ Pollut ; 263(Pt A): 114596, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32325357

RESUMO

Plastic debris has become a major threat to the marine environment and wildlife. Sea turtles are particularly vulnerable, and are known to ingest plastic debris globally; however, information from Greek waters is still absent. In this study, 36 stranded dead loggerhead turtles (Caretta caretta) were collected from the Greek coastline area, and their gastrointestinal content was analysed for ingested plastic debris. Twenty-six individuals (72%) were found to have ingested plastic, with an average of 7.94 ± 3.85 (SE) plastic items per turtle. In total, 286 plastic items were counted and categorised by size, shape, colour, and polymer type. Fourier Transform Infrared Spectrometry revealed that polypropylene and polyethylene were the dominant polymer plastic types found. Results indicated a variation in plastic ingestion amongst life stages of the loggerhead specimens. This study provides evidence of plastic ingestion by loggerhead turtles in Greek waters.


Assuntos
Tartarugas , Poluentes da Água/análise , Animais , Grécia , Mar Mediterrâneo , Plásticos
19.
Mar Pollut Bull ; 153: 111012, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32275558

RESUMO

The present study sought to determine bioaccumulation and potential molecular effects of four of the most environmentally significant sunscreen agents in juvenile loggerhead sea turtles (Caretta caretta) from the Italian coasts of the central Adriatic Sea. Each of these sunscreen agents were found in most of the plasma samples analyzed, with benzophenone-3 as the dominant species. Total concentrations of the sunscreen agents ranged from not detected (

Assuntos
Monitoramento Ambiental , Protetores Solares/análise , Tartarugas , Poluentes da Água/análise , Animais , Biomarcadores , Inflamação , Estresse Oxidativo
20.
Mar Pollut Bull ; 153: 111023, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32275569

RESUMO

Plastic litter in nearshore waters is an environmental pollutant with increasing impact on coastal environments. At present, knowledge on basic plastic particle dynamics and the interaction with complex hydrodynamics is lacking. The present laboratory study, performed under controlled wave and wind conditions, demonstrates the dispersion of plastics in shallow waters. The study presents a simple case looking solely at cross-shore particle transport. The results show that both wind and waves as well as plastic properties (shape and density) govern the behaviour of plastic litter in the nearshore zone. Heavy particles behave like natural sand with accumulation in the wave breaking zone. Light particles have varying accumulation along the coastal profile depending on the wind, waves and particle shapes. More extensive characterization remains to be done in future studies.


Assuntos
Monitoramento Ambiental , Plásticos , Poluentes da Água/análise , Vento , Hidrodinâmica , Laboratórios
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