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1.
Environ Pollut ; 258: 113688, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32004855

RESUMO

The automatic identification (location, segmentation, and classification) by UAV- based optical imaging of spills of transparent floating Hazardous and Noxious Substances (HNS) benefits the on-site response to spill incidents, but it is also challenging. With a focus on the on-site optical imaging of HNS, this study explores the potential of single spectral imaging for HNS identification using the Faster R-CNN architecture. Images at 365 nm (narrow UV band), blue channel images (visible broadband of ∼400-600 nm), and RGB images of typical HNS (benzene, xylene, and palm oil) in different scenarios were studied with and without Faster R-CNN. Faster R-CNN was applied to locate and classify the HNS spills. The segmentation using Faster R-CNN-based methods and the original masking methods, including Otsu, Max entropy, and the local fuzzy thresholding method (LFTM), were investigated to explore the optimal wavelength and corresponding image processing method for the optical imaging of HNS. We also compared the classification and segmentation results of this study with our previously published studies on multispectral and whole spectral images. The results demonstrated that single spectral UV imaging at 365 nm combined with Faster R-CNN has great potential for the automatic identification of transparent HNS floating on the surface of the water. RGB images and images using Faster R-CNN in the blue channel are capable of HNS segmentation.


Assuntos
Substâncias Perigosas/análise , Hidrocarbonetos/análise , Redes Neurais de Computação , Poluição Química da Água/análise , Poluição por Petróleo/análise , Análise Espectral
2.
Chemosphere ; 239: 124770, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31726525

RESUMO

Over twenty thousand persons rely on water from Atuwara River for drinking and other domestic purposes, hence the need to ascertain the human health risk inherent in such practice. Seventy-two water samples were collected from River Atuwara during the dry and wet seasons of 2018, and the concentration of heavy metals (Pb, As, Ni, Cr, Zn, Cu, and Cd) were measured using ICP-OES. A newly developed human health risk assessment method, HHRISK code was used to estimate the health risks associated with consumption of water from Atuwara River. Results obtained revealed that the concentration of heavy metals in the river was as follows: Cd < Ni < Pb < Cr < Cu < As < Zn in the wet season and Cd < Pb < Ni < Cu < Cr < As < Zn during the dry season. Principal component analysis suggested that industrial effluents, agricultural activities and base-rock interaction are responsible for pollution of Atuwara River. The cumulative hazard index (HIcum) obtained was 678.0 ±â€¯36.8 (for adult) and 1392.0 ±â€¯132 (for child) for non-carcinogenic risks. A cumulative carcinogenic risk (CRcum) of 1.01E-1±5.26E-3 and 4.96E-2±5.05E-3 was obtained for adult and children respectively, suggesting that up to 1 in 10 adults and 1 in 20 children may suffer from cancer over their lifetime as a result of consumption and exposure to water from River Atuwara. These results highlight the fact that unavailability of safe drinking water in many parts of the world remains a real and persistent risk which must be tackled.


Assuntos
Água Potável/química , Monitoramento Ambiental/métodos , Metais Pesados/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , Adulto , Agricultura , Criança , Humanos , Nigéria , Análise de Componente Principal , Medição de Risco , Rios , Estações do Ano , Qualidade da Água
3.
Chemosphere ; 238: 124604, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31450113

RESUMO

Accurate in silico predictions of chemical substance ecotoxicity has become an important issue in recent years. Most conventional methods, such as the Ecological Structure-Activity Relationship (ECOSAR) model, cluster chemical substances empirically based on structural information and then predict toxicity by employing a log P linear regression model. Due to empirical classification, the prediction accuracy does not improve even if new ecotoxicity test data are added. In addition, most of the conventional methods are not appropriate for predicting the ecotoxicity on inorganic and/or ionized compounds. Furthermore, a user faces difficulty in handling multiple Quantitative Structure-Activity Relationship (QSAR) formulas with one chemical substance. To overcome the flaws of the conventional methods, in this study a new method was developed that applied unsupervised machine learning and graph theory to predict acute ecotoxicity. The proposed machine learning technique is based on the large AIST-MeRAM ecotoxicity test dataset, a software program developed by the National Institute of Advanced Industry Science and Technology for Multi-purpose Ecological Risk Assessment and Management, and the Molecular ACCess System (MACCS) keys that vectorize a chemical structure to 166-bit binary information. The acute toxicity of fish, daphnids, and algae can be predicted with good accuracy, without requiring log P and linear regression models in existing methods. Results from the new method were cross-validated and compared with ECOSAR predictions and show that the new method provides better accuracy for a wider range of chemical substances, including inorganic and ionized compounds.


Assuntos
Ecotoxicologia/métodos , Aprendizado de Máquina , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/análise , Animais , Simulação por Computador , Daphnia/efeitos dos fármacos , Peixes , Modelos Lineares , Modelos Teóricos , Relação Quantitativa Estrutura-Atividade , Medição de Risco/métodos , Software , Poluentes Químicos da Água/química
4.
Chemosphere ; 238: 124688, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524623

RESUMO

Microplastic pollution has received increased attention recently due to potential threat to marine biota and human health. This study reports microplastic (MP) content in brown shrimp (Metapenaeus monocerous) and tiger shrimp (Penaeus monodon) inhabiting in the shallow and offshore waters of the Northern Bay of Bengal, Bangladesh. Gastrointestinal tract (GT) of shrimps (n = 150) were examined for MPs following alkali digestion, microscopic observation and chemical analysis by micro-Fourier Transformed Infrared Spectroscope (µFTIR). A total of 33 and 39 MP items were found in P. monodon and M. monocerous, averaging 3.40 ±â€¯1.23 and 3.87 ±â€¯1.05 items/g GT, respectively. Among various shapes, types and colours of MP, filament (57-58%), fiber (32-57%) and black (48-51%) were dominant amongst the various particles identified. Tiger shrimp had high numbers (23 items) of larger size fractions of MPs (1-5 mm) but brown shrimp had high numbers (15 items) of smaller MPs (250-500 µm), and µ-FTIR data confirmed 13 particles of polyamide-6 and 6 particles of rayon polymers. These results provide a baseline of MP contamination in seafood from Bangladesh that should be useful for future monitoring efforts.


Assuntos
Caprolactama/análogos & derivados , Celulose/análise , Monitoramento Ambiental/métodos , Microplásticos/análise , Penaeidae/química , Polímeros/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , Animais , Bangladesh , Baías/química , Caprolactama/análise , Trato Gastrointestinal/química , Alimentos Marinhos/análise , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Environ Monit Assess ; 191(11): 663, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31650250

RESUMO

In order to acquire the spatial distribution, speciation, and risk assessment of arsenic (As), 18 sediment samples were collected in the middle and upper reaches (Nanpan River, Beipan River, Hongshui River, Diaojiang River, and Duliu River) of the Xijiang River basin, China. The chemical fractions of As in the collected sediments were mainly dominated by the residual fraction and the Fe (Mn, Al) oxide/oxyhydroxides fractions. The correlation analysis results showed that the chemical fraction of As in sediments had close correlations with Mn, good correlations with Fe and organic matter (OM), while weak correlations with Al and carbonate. In addition, it also showed that Diaojiang River basin was found to have an extremely high As pollution status and suffered from high ecological risk. Duliu River and Nanpan River had moderately polluted levels of As and showed a low ecological risk. The other sample sites of Xijiang River basin were uncontaminated of As. The assessment results from this study indicated that the different types of species present based on the chemical fractionation of As from the Xijiang River basin showed different risks. Graphical abstract.


Assuntos
Arsênico/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , Carbonatos/análise , China , Ecologia , Metais Pesados/análise , Medição de Risco , Rios/química
6.
Environ Monit Assess ; 191(11): 652, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628537

RESUMO

In the last few years, several studies have investigated microplastics (MPs) in marine ecosystems, but data monitoring and assessing the occurrence in freshwater environments are still scarce. The present study aims to investigate the occurrence, distribution, and chemical composition of MP pollution in Vesijärvi lake and Pikku Vesijärvi pond close to the city of Lahti (Finland) in winter. Sediment, snow, and ice core samples were collected near the shore of these two aquatic systems. MPs were analysed and identified by a non-destructive method using Fourier transform infrared spectroscopy (FTIR) 2D imaging. The mean concentrations of MPs detected in sediment, snow, and ice samples were 395.5 ± 90.7 MPs/kg, 117.1 ± 18.4 MPs/L, and 7.8 ± 1.2 MPs/L, respectively. FTIR results showed the predominant abundance of microplastics, such as polyamides (up to 53.3%), polyethylene and polypropylene (up to 17.1%), and natural fragments such as cellulose (up to 45.8%) and wool (up 18.8%) in the same size range. The potential release of MPs arising from stormwaters and sport and recreational activities was evidenced.


Assuntos
Monitoramento Ambiental/métodos , Tanques/química , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , Animais , Celulose/análise , Ecossistema , Finlândia , Lagos/química , Nylons/análise , Polietileno/análise , Polipropilenos/análise , Espectroscopia de Infravermelho com Transformada de Fourier
7.
J Agric Food Chem ; 67(45): 12402-12407, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31663732

RESUMO

The hydrolysis of chlorantraniliprole (3-bromo-N-[4-chloro-2-methyl-6-(methylcarbamoyl)phenyl]-1-(3-chloro-2-pyridine-2-yl)-1H-pyrazole-5-carboxamide; CAP) was investigated over the pH range of 6-10, reflective of California rice field conditions, with variable additions of Cu2+, Zn2+, Mn2+, or Ni2+. Dissipation accelerated as pH increased with half-lives ranging from 26.9 to 2.2 days with slight inhibition in rice field water. The addition of divalent metals was not observed to catalyze the hydrolysis of CAP at pH 6, indicating that the insecticide is likely to remain recalcitrant to hydrolysis in neutral or acidic surface waters. However, Mn2+ and Ni2+ were observed to inhibit hydrolysis at pH 8 and 9. Attenuated total reflectance Fourier transform infrared analysis supports the conclusion that divalent metals may withdraw electron density from the amide nitrogen via interaction with the amide oxygen, though additional quantum chemical modeling is necessary to provide further mechanistic insights. Overall, the hydrolysis of CAP in California rice fields and their surrounding surface waters will be dominated by pH and inhibited by dissolved metal species.


Assuntos
Hidróxidos/química , Inseticidas/química , Metais/química , Oryza/crescimento & desenvolvimento , Poluição Química da Água/análise , ortoaminobenzoatos/química , California , Concentração de Íons de Hidrogênio , Hidrólise
8.
Artigo em Inglês | MEDLINE | ID: mdl-31533232

RESUMO

Due to extensive pollution and the relatively weak flow replacement in urban rivers, determining how to fully utilize the self-purification abilities of water bodies for water quality protection has been a complex and popular topic of research and social concern. Organic pollution is an important type of urban river pollution, and COD (chemical oxygen demand) is one of the key pollution factors. Currently, there is a lack of research on the relationship between COD degradation and the flow characteristics of urban rivers. In this paper, COD degradation experiments were conducted in an annular flume with Jinjiang River water at controlled flow velocities and the COD degradation coefficients under different hydraulic conditions were analyzed. A good correlation was observed between the degradation coefficient and hydraulic conditions. According to dimensional analysis, the relationship between the COD degradation coefficient and hydraulic conditions such as the flow velocity, water depth, Reynolds number (Re), and Froude number (Fr) was established as K COD = 86400 u h F r 0.8415 R e - 1.2719 + 0.258 . The COD degradation coefficients of the Chishui River in Guizhou Province ranged from 0.175-0.373 1/d based on this formula, and the field-measured values varied from 0.234-0.463 1/d. The error in the formula ranged from 5.4-25.3%. This study provides a scientific basis for the prediction of the COD degradation coefficients of urban rivers.


Assuntos
Análise da Demanda Biológica de Oxigênio , Rios/química , Poluição Química da Água/análise , Qualidade da Água , China , Cidades , Hidrodinâmica
9.
Arch Environ Contam Toxicol ; 77(4): 527-536, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31494698

RESUMO

Vieira River is the main recipient of domestic and industrial wastewater in the city of Montes Claros, MG, Brazil. Until 2010, domestic sewage was dumped in it without any kind of treatment. Concentrations of arsenic (As), chrome (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) were determined in water and sediment samples in eight locations along the Vieira River during the dry season of 2015. Concentrations of Cu, Ni, and Zn detected in the water at some sites along the Vieira River were superior to the reference limits for toxicity. The concentration of Cu and Ni restricts the use of water for irrigation in some sites of the river. The level of sediment contamination was assessed by five approaches, including contamination factor (CF), pollution load index (PLI), geo-accumulation index (Igeo), cluster analysis (CA), and principal component analysis/factor analysis (PCA/FA). The results showed that Cr and the downstream sampling site nearest to the Wastewater Treatment Plant of the city of Montes Claros had the highest values of PLI, Igeo, and CF, which reinforces the influence of domestic and industrial wastewater discharge in pollution of the Vieira River. In addition, CA and PCA/FA reinforced the assumption that Cr comes from anthropogenic pollution sources.


Assuntos
Sedimentos Geológicos/análise , Metais/análise , Rios/química , Poluentes Químicos da Água/análise , Brasil , Cidades , Monitoramento Ambiental/métodos , Metais Pesados/análise , Análise de Componente Principal , Estações do Ano , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluição Química da Água/análise
10.
Environ Pollut ; 255(Pt 1): 113133, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31536879

RESUMO

As a new type of emerging pollutant in the ocean, microplastics have received global attention in recent years. Considering the increasing amount of human activities around the South China Sea, it is important to determine the current status of microplastic pollution in this region. In this study, we analyzed the abundance and distribution of microplastics at Zhubi Reef in the South China Sea. Microplastic abundance ranged from 1400 to 8100 items/m3 of surface water, which was much higher than the values reported from other ocean areas. About 80% of the microplastics were smaller than 0.5 mm in size. Fibers and pellets comprised the most common microplastic types. The dominant microplastics were transparent or blue in color. The main polymer types were polypropylene (25%) and polyamide (18%). In general, our results revealed Zhubi Reef was contaminated with microplastics, which were likely derived from the intensive fisheries in the area and emissions from coastal cities. This study also provides baseline data that are useful for additional studies of microplastics in the South China Sea.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , China , Cidades , Recifes de Corais , Nylons/análise , Polipropilenos/análise
11.
J Environ Sci Health B ; 54(12): 915-924, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31397192

RESUMO

In order to assess the risk of exposure of human populations to dichlorodiphenyltrichloroethane (DDT) and mercury, muscles of five fish species were analysed, along with the surface sediment of 14 Iriri River sampling sites. The fish specimens were sacrificed by the spinal section, prior to sex identification, body weight determination and total length. Considering the fish specimens studied, 11% of them showed concentrations of mercury higher than the maximum established by the World Health Organization for safe human consumption. A positive correlation between fish body weight and mercury concentration was observed, besides a positive correlation between the fish size and Hg concentration. Significant differences (P < 0.05) were found between mean concentrations of DDT and metabolites among species of fish studied. In the Plagioscion squamossissimus species, the highest concentration of total DDT (151.4 ng/g) was found, while in Eugerres Brasilianus species, the lowest. However, the DDT levels in fish muscle of studied species are below the maximum set by FAO-Alimentarius CODEX. In the sediments, total DDT ranged from 11.58 ng/g to 48.4 ng/g, which is associated with the historical DDT use in the Amazon. According to sediment quality guidelines, these levels have a moderate toxic effect in almost all of the studied region.


Assuntos
DDT/análise , Sedimentos Geológicos/análise , Mercúrio/análise , Rios/química , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Animais , Brasil , Peixes , Contaminação de Alimentos/análise , Humanos , Poluição Química da Água/análise
12.
Artigo em Inglês | MEDLINE | ID: mdl-31370179

RESUMO

The geologic profile of the western United States lends itself to naturally elevated levels of arsenic and uranium in groundwater and can be exacerbated by mining enterprises. The Navajo Nation, located in the American Southwest, is the largest contiguous Native American Nation and has over a 100-year legacy of hard rock mining. This study has two objectives, quantify the arsenic and uranium concentrations in water systems in the Arizona and Utah side of the Navajo Nation compared to the New Mexico side and to determine if there are other elements of concern. Between 2014 and 2017, 294 water samples were collected across the Arizona and Utah side of the Navajo Nation and analyzed for 21 elements. Of these, 14 elements had at least one instance of a concentration greater than a national regulatory limit, and six of these (V, Ca, As, Mn, Li, and U) had the highest incidence of exceedances and were of concern to various communities on the Navajo Nation. Our findings are similar to other studies conducted in Arizona and on the Navajo Nation and demonstrate that other elements may be a concern for public health beyond arsenic and uranium.


Assuntos
Arsênico/análise , Água Subterrânea/química , Índios Norte-Americanos , Urânio/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Qualidade da Água , Arizona , Regulamentação Governamental , Água Subterrânea/análise , Humanos , Mineração , New Mexico , Utah , Poluição Química da Água/análise
13.
Mar Pollut Bull ; 148: 97-106, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422308

RESUMO

This study provides the first measurement of microplastic abundance and distribution in surface waters and sediments in Tampa Bay, FL. Microplastic concentrations in discrete water samples ranged from 0.25 to 7.0 particles/L with an average of 0.94 (±0.52) particles/L. Samples taken with a 330 µm plankton net had 1.2-18.1 particles/m3 with an average of 4.5 (±2.3) particles/m3. Discrete samples were 200 times higher than net samples, suggesting substantial losses or undersampling with the net. For both discrete and plankton tow samples, there were no significant differences in concentrations between stations or regions. Intense rainfall events in the summer always preceded samples with substantially higher counts. Most (>75%) microplastics were fibers. Using an average value of 1 particle/L, Tampa Bay contains ~4 billion microplastic particles. Surface sediments had an average of 280 (±290) particles/kg, ranging from 30 to 790 particles/kg. Highest concentrations of microplastics were found in sediments close to industrial sources; lowest values in Middle and Lower Tampa Bay are consistent with shorter residence times.


Assuntos
Sedimentos Geológicos/análise , Poluentes Químicos da Água/análise , Baías/análise , Monitoramento Ambiental , Estuários , Florida , Plâncton/crescimento & desenvolvimento , Plâncton/metabolismo , Estações do Ano , Poluição Química da Água/análise
14.
Environ Pollut ; 254(Pt A): 112970, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31377328

RESUMO

To broaden the understanding of sources, pathways and sinks for microplastic pollution in the environment, the exact and representative determination of pollution levels is crucial. Still, sampling techniques differ greatly between studies and the influence of these differences is not fully understood. Thus, we evaluate the representativeness of manta trawling and pump sampling for microplastics in a freshwater lake. While large microplastics are not captured by most pump sampling approaches due to their low abundance, small and fibrous microplastics pass the relatively coarse nets of volume-reduced techniques. Testing different water volumes for pump samples, we show that sample volumes should be large enough to minimize overestimation induced by scaling up results. Moreover, we discuss the influence of sample numbers for microplastic analysis. Finally, we argue that manta trawling and pump sampling are complementary techniques, as they cover different parts of the overall microplastic pollution.


Assuntos
Monitoramento Ambiental/métodos , Lagos/química , Plásticos/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , Nanoestruturas/análise
15.
Mar Pollut Bull ; 146: 22-25, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426150

RESUMO

Here we summarize the overarching issues that emerged from a workshop held to discuss scientific challenges and future directions on the use of numerical models to predict the amount, distribution and effects of plastic pollution on marine ecosystems. The need for multi-disciplinary approaches, standardized protocols for plastic quantification and analyses, using realistic contaminant concentrations in laboratorial experiments and targeting early-life stages of marine organisms were pointed out as needs to improve data accuracy. Participants also enumerated a list of gaps that include, identification of indicator organisms of plastic contamination, selection of biomarkers and the role of extreme events on plastic dynamics. Responding to these gaps will contribute to improve data quantity and quality and, thus, allow developing more reliable models. A crucial role is foreseen for modelling tools as they can incorporate the cumulative impacts of multiple stressors, including the individual-level effects of plastics, to the population- and ecosystem level.


Assuntos
Plásticos/análise , Água do Mar/análise , Poluentes Químicos da Água/análise , Organismos Aquáticos/efeitos dos fármacos , Organismos Aquáticos/crescimento & desenvolvimento , Mudança Climática , Ecossistema , Monitoramento Ambiental , Plásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/análise
16.
Mar Pollut Bull ; 146: 39-49, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426172

RESUMO

This study investigated polycyclic aromatic hydrocarbons (PAHs) and organochlorine compounds such as polychlorinated biphenyls (PCBs) and DDT-related pesticides in surface sediments of Hooghly estuary and the Sundarban mangrove wetlands. Concentrations of ∑17PAH, ∑182PCB and ∑6DDT ranged from 15.4 to 1731, not detected (nd) to 13.5 and nd to 8.97 ng g-1 dry weight, respectively. Low levels of PCBs and low to moderate concentrations of DDTs and PAHs reflected recent development in West Bengal, which was dominated by agriculture and multifarious industries in the past. Diagnostic ratios suggested that major sources of PAHs are combustion processes, DDTs are input by agriculture, antifouling paints and public health campaigns, and organochlorines are predominantly from industrial origin. Heavier PCB congeners suggest local sources and short-range transport of such chemicals. Decision makers may use these findings for managing the Hooghly River watershed in order to promote a sustainable development on the eastern coast of India.


Assuntos
Rios/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Estuários , Sedimentos Geológicos/química , Hidrocarbonetos Clorados/análise , Índia , Praguicidas/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluição Química da Água/análise , Áreas Alagadas
17.
Mar Pollut Bull ; 146: 60-66, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426199

RESUMO

We present here the first estimates of floating macro-litter in surface waters from the Rhone River, based on monthly visual observations during 1-year period (2016-2017). Plastic represented 77% of the identified items, confirming its predominance in riverine floating litter. Fragments (2.5-50 cm) and Single Use Plastics (i.e. bags, bottles and cover/packaging) were among the most abundant items. Frequent non-plastic floating litter were paper items such as packaging material and newspapers, and metal items (mostly cans), representing 14% and 5% of total litter, respectively. A lower-end estimate resulted in ∼223,000 plastic items (∼0.7 t of plastic) transported annually by the Rhone surface waters to the Gulf of Lion (NW Mediterranean Sea). Floating macro-plastics are only a fraction of the total plastic export by the Rhone. Our study highlights the current discrepancy between field observations and theoretical estimations. Improvements are needed to harmonize data collection methodologies for field studies and model validation.


Assuntos
Plásticos/análise , Rios/química , Poluição Química da Água/análise , Monitoramento Ambiental , Mar Mediterrâneo
18.
Mar Pollut Bull ; 146: 683-695, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426210

RESUMO

The Eastern Arabian Sea (EAS) is affected by oil pollution, as often evidenced by the presence of tarballs along the West Coast of India (WCI). Tarball samples collected during May 2017 along the Goa coast were subject to biomarker fingerprints, and the results matched with Bombay High (BH) oil fingerprints. The present study primarily aims at identifying the potential minor spill areas using Sentinel-imagery. Interestingly, repeated occurrence of oil spills detected at two locations, perfectly matched with BH platforms. The simulated Lagrangian trajectories also depict that tarball particles have originated from those detected locations. In 2017 alone, the quantity of spilled oil was estimated to be 129,392 l. However, spills detected offshore regions of Kachchh and Mangalore were found to be caused by ships. This is the first comprehensive study, tracking the oil pollution sources in the EAS through multi-technique approach - chemical, remote sensing and numerical modeling.


Assuntos
Monitoramento Ambiental/métodos , Poluição por Petróleo/análise , Poluição Química da Água/análise , Índia , Petróleo/análise , Tecnologia de Sensoriamento Remoto/métodos , Navios , Astronave , Triterpenos/análise , Poluentes Químicos da Água/análise
19.
Rev Esp Salud Publica ; 932019 Aug 28.
Artigo em Espanhol | MEDLINE | ID: mdl-31462628

RESUMO

The use of plastics has increased exponentially over recent years. Difficulties in their recycling and their low degradability result in their accumulation in the environment. Despite their great stability, they are subject to physical and chemical erosion resulting in smaller fragments. Although there is no standard definition of microplastics, the maximum limit of 5 mm has been accepted as a criterion. Plastics, in addition to the consequences on the environment, have a direct effect on living beings, either by ingestion or toxicity. They may also act as a vehicle for invasive species and adsorb other contaminants on their surface such as PCBs, PAHs or DDT. This, increases the toxic effect of their own components such as plasticizers, additives, heavy metals, etc. There is disparity in the published results regarding the presence of microplastics in both water supplies and drinking water and bottled water. There are no standard analytical methods, nor a consensus in the definition and description of microplastics that allow an appropriate comparison of results. In the absence of scientific evidence, it is necessary to study in depth the presence of microplastics in water and the potential effects on health, in order to be able to consider microplastics as a monitoring parameter in drinking water.


Assuntos
Água Potável , Saúde Pública , Poluentes Químicos da Água , Poluição Química da Água , Água Potável/efeitos adversos , Água Potável/química , Monitoramento Ambiental/legislação & jurisprudência , União Europeia , Saúde Global , Política de Saúde , Humanos , /toxicidade , Nações Unidas , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/efeitos adversos , Poluição Química da Água/análise , Poluição Química da Água/legislação & jurisprudência , Poluição Química da Água/estatística & dados numéricos
20.
Environ Sci Pollut Res Int ; 26(26): 27073-27086, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31317434

RESUMO

Assessing the potential impacts of nonpoint source (NPS) pollution and proposing sound control strategies are significant global challenges. However, few studies have provided insights into the quantitative risk analysis and efficient management of NPS pollution. This study formulated four evaluation criteria to characterize both the generation and migration of diffuse phosphorus. Multicriteria analysis and the technique for order preference by similarity to ideal solution were combined to develop a NPS pollution risk index model for the evaluation of the potential phosphorus loss at the basin scale. The proposed model is a simple and efficient tool that considers most factors that affect diffuse phosphorus. In the GIS environment, the spatial distribution of the risk index of diffuse phosphorus could be mapped and visualized in the Huai River Basin. With the natural breaks classification method, the study area was divided into the following five regions: a potentially polluted region (3.5%), a lightly polluted region (15.4%), a moderately polluted region (40.7%), a highly polluted region (31.5%), and a seriously polluted region (8.9%). Based on land use composition, geographical location, and sources of diffuse phosphorus of these five regions, corresponding prevention measures were introduced, thus facilitating the management of NPS pollution for policy makers.


Assuntos
Modelos Teóricos , Poluição Difusa/análise , Fósforo/análise , Poluição Química da Água/análise , China , Visualização de Dados , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Rios
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