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1.
Toxics ; 12(6)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38922119

RESUMO

This study investigates the occurrence and characteristics of macroplastic and polymer microparticles in the Urias coastal lagoon's beach sediments, in northwest Mexico. Coastal lagoons, productive and vulnerable ecosystems, are impacted significantly by anthropogenic activities, leadings to their pollution by various contaminants, including plastics. Our research involved sampling sediments from four sites within the lagoon that were influenced by different human activities such as fishing, aquaculture, thermoelectric power plant operations, industrial operations, and domestic wastewater discharge. Our methodology included collecting macroplastics and beach sediment samples, followed by laboratory analyses to identify the plastic debris' size, shape, color, and chemical composition. The results indicated a notable presence of macroplastic items (144), predominantly bags, styrofoam, and caps made of polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET). The polymer microparticles were mainly fibers, with cotton and polyester as the most common polymers, suggesting a significant contribution from clothing-related waste. The dominant colors of the microparticles were blue and transparent. High densities were observed in areas with slower water exchange. Our findings highlight the urgent need for better waste management practices to mitigate plastic pollution in coastal lagoons, preserving their ecological and economic functions.

2.
Sci Total Environ ; 922: 171283, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38423331

RESUMO

Microplastic identification and distribution throughout oceans has become a great concern due to its substantial uprising and its consequent interactions with marine biota. Microplastics can be absorbed and adsorbed by several marine species owing to their very small size. Among these organisms are bivalves, including ones used as food for humans. In this context, this research aims to understand the absorption scale of microplastics by Tivela mactroides according to their size and consequently life stage. Thus, T. mactroides mussels were collected at Camburi Beach (Brazil) and grouped into 30 different size classes from 06 to 35 mm. Later, 20 specimens from each size class (N = 600) had the soft tissues removed and a pool was performed through digestion with 10 % KOH solution. Results showed the presence of microplastics in all size classes of T. mactroides, evidencing that organisms from 06 mm can already be contaminated by microplastics and a tendency of the number of microplastics particles to increase as shell size increases. Furthermore, the amount of blue filament-type MPs was significantly higher than the other types and colors. Additionally, analyzes performed by Raman spectroscopy showed that the blue filaments have a PET composition. Finally, larger individuals presented larger quantities of MPs, as well as larger filaments. This might suggest that there are differences between the assimilation of the size of MPs in the different size classes, i.e. that size makes a difference.


Assuntos
Bivalves , Poluentes Químicos da Água , Humanos , Animais , Microplásticos , Plásticos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise
3.
Mar Environ Res ; 198: 106516, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38678751

RESUMO

The accumulation of heavy metals from sewage and garbage dumping can seriously impact beach tourism and thus the local economy, but it is difficult to quickly and accurately determine the pollution location and source of heavy metals and clarify their diffusion range. This study investigates a new in situ magnetic testing method to address this issue. (1) The in situ method can be used to effectively and quickly evaluate heavy metal sources and diffusion ranges based on the distribution of κ values. (2) According to chemical experiments, the specific elements polluting a beach can be determined, such as the Cr, Ni, Zn, and Fe pollution of Beach No. 3. (3) Although κ values for assessing heavy metal pollution on different beaches vary, metal pollution occurs when the higher κ value is more than 50 times the lower κ value on the same beach. (4) The κ values vary in different seasons due to the influence of natural factors and urban seasonal sewage policies.


Assuntos
Praias , Monitoramento Ambiental , Metais Pesados , Estações do Ano , Poluentes Químicos da Água , China , Metais Pesados/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Esgotos/química , Esgotos/análise
4.
Sci Total Environ ; 857(Pt 3): 159352, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36257412

RESUMO

In coastal areas, microplastics (MPs) can deposit in sediment, allowing it to be ingested by benthic organisms, like mussels, thus creating a possible transfer to humans. The aim of this study is to evaluate MPs pollution in sediment as a function of shoreline elevation in two urbanized beaches and to evaluate the abundance/frequency of MPs in 4 different species of bivalves commonly used in the human diet, such as the oyster Crassostrea brasiliana, the mussels Mytella strigata and Perna perna and the clam Tivela mactroides, and identify the polymers via µ-FTIR technique. A total of 3337 MPs were found in this study, of which 1488 were found in the sediment at the five sites analyzed, and 1849 in the bivalve tissues at the two sampling sites. MPs contamination was observed in all sediment samples and species of the pool and in each of the 10 specimens of the four species. Thus, the frequency of contamination by MPs reached 100 % for the analyzed samples. The number of filaments is higher than fragments in sediment samples and in each bivalve species. Regarding types and colors, the blue were greater than fragment-type in sediments and samples. In an effort to classify the polymers via µ-FTIR, our study was able to identify polypropylene, polyethylene and polyethylene terephthalate, besides a great number of cellulose fibers.


Assuntos
Bivalves , Poluentes Químicos da Água , Animais , Humanos , Microplásticos , Plásticos , Sedimentos Geológicos , Brasil , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise
5.
Mar Pollut Bull ; 181: 113831, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35714545

RESUMO

This study is the first attempt to provide original data on plastics debris occurrence in beach sediments of the Gulf of Skikda in Algeria (southwestern Mediterranean). Sediment samples from seven beaches were collected to extract, quantify and characterize mesoplastics and microplastics. Particles were classified by size into mesoplastics (5-25 mm) and large microplastics (1-5 mm). Overall, microplastics were the most abundant size fraction in terms of number of items. The average mass of mesoplastics was twice that of microplastics, revealing a notable reservoir of plastics that is scarcely ever reported in the literature. The predominant types were fragments and pellets, white/transparent in color. The average concentrations of total plastic were 1067.19 ± 625.62 items/m2, 106.98 ± 62.39 items/kg, and 50.65 ± 9.82 g/m2, showing variability between beaches and within sampling sites. Thus, the Skikda coast has high levels of pollution compared to other areas of the Mediterranean Sea.


Assuntos
Plásticos , Poluentes Químicos da Água , Argélia , Monitoramento Ambiental , Sedimentos Geológicos , Microplásticos , Resíduos/análise , Poluentes Químicos da Água/análise
6.
Environ Pollut ; 305: 119297, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35421552

RESUMO

Microplastics (MPs) are a global environmental concern and pose a serious threat to marine ecosystems. This study aimed to determine the abundance and distribution of MPs in beach sediments (12 beaches), marine biota (6 beaches) and the influence of microbes on MPs degradation in eco-sensitive Palk Bay and Gulf of Mannar coast. The mean MP abundance 65.4 ± 39.8 particles/m2 in beach sediments; 0.19 ± 1.3 particles/individual fish and 0.22 ± 0.11 particles g-1 wet weight in barnacles. Polyethylene fragments (33.4%) and fibres (48%) were the most abundant MPs identified in sediments and finfish, respectively. Histopathological examination of fish has revealed health consequences such as respiratory system damage, epithelial degradation and enterocyte vacuolization. In addition, eight bacterial and seventeen fungal strains were isolated from the beached MPs. The results also indicated weathering of MPs due to microbial interactions. Model simulations helped in tracking the fate and transboundary landfall of spilled MPs across the Indian Ocean coastline after the X-Press Pearl disaster. Due to regional circulations induced by the monsoonal wind fields, a potential dispersal of pellets has occurred along the coast of Sri Lanka, but no landfall and ecological damage are predicted along the coast of India.


Assuntos
Desastres , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Peixes , Sedimentos Geológicos , Índia , Microplásticos , Plásticos , Poluentes Químicos da Água/análise
7.
Mar Pollut Bull ; 176: 113409, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35168068

RESUMO

Marina beach in Chennai metropolitan city attracts numerous tourists from all around the world, and it is an important ecological habitat for many life forms. Rapid urbanisation and industrial developments have led to excessive use of plastics and increased the amount of plastic waste generated in the natural environment. This first baseline study evaluates the microplastic (MP) accumulation in beach surface sediments of Marina and Pattinapakkam beaches through FTIR, AFM and SEM analyses. Sediment samples were collected from 40 stations and different types of MP polymers were identified. On average, 459 (60.8%) and 297 (39.2%) MP particles were found in the samples from Marina and Pattinapakkam beaches, respectively. We found that polyethylene types and additives are the dominant MPs in both areas. This study provided us with new insights into the human activities and natural processes in these marine environments. To solve the problem of plastic accumulation in the marine environment, the government should first play an active role in addressing the problem of plastic waste by introducing laws to control the sources of plastic waste and the use of plastic additives.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos/análise , Humanos , Índia , Plásticos/análise , Poluentes Químicos da Água/análise
8.
Sci Total Environ ; 813: 152650, 2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-34954167

RESUMO

The pervasive existence of microplastics (MPs) and toxic metals is raising environmental and health concerns. Plastics are essentially a complex mixture of chemicals, but exposure to the aquatic environment increases their complexity through contaminant desorption/sorption. The aim of this study was to establish baseline data on the elemental occurrence and distribution of potentially toxic and geochemical metals/metalloids in microplastics 1-5 mm and mesoplastics (> 5 mm - 1 cm) along designated coastlines of the Gulf of Guinea (Nigeria) in addition to enabling more comprehensive ecotoxicological risk assessment. The concentrations of twenty-six metals: aluminium (Al), antimony (Sb), arsenic (As), barium (Ba), boron (B), cadmium (Cd), calcium (Ca), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), potassium (K), selenium (Se), sodium (Na), silicon (Si), silver (Ag), strontium (Sr), thallium (Tl), titanium (Ti), vanadium (V), and zinc (Zn), associated with beach MPs, pristine, and lagoon plastics were determined after extraction in 10% nitric acid and analysis using inductively coupled plasma-optical emission spectroscopy (ICP-OES). The distribution of MPs was variable, with 3680 particles identified along the drift and high waterlines across designated shoreline locations. The beach MPs were dominated by polyethylene (PE), polypropylene (PP), and polystyrene (PS), whereas lagoon-sourced plastics were characterized by polyethylene terephthalate (PET), polystyrene (PS), and polyurethane (PUR). Metal concentration was higher when associated with foam plastic (PS, PUR, PEVA) compared to hard plastic (PE, PP, PET) samples. The results showed that all samples had slightly elevated Al, Fe, Mn, and Zn concentrations, suggesting potential sorption interactions and plastic additive influences. Notably, foam MPs had a stronger affinity for metals. This study emphasizes the critical role of microplastics in serving as vectors for toxic metals. Except for Cd, pollution indices such as the potential contamination index (PCI), hazard quotient (HQ), and modified hazard quotient (mHQ) indicated low severity contamination of beach and lagoon MPs by heavy metals. However, considering long-term accumulation of sorbed metals, their potential toxicity to marine biota may be considerable.


Assuntos
Metaloides , Metais Pesados , Monitoramento Ambiental , Guiné , Metais Pesados/análise , Microplásticos , Plásticos
9.
Environ Sci Pollut Res Int ; 29(50): 75525-75538, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35657544

RESUMO

Microplastics accumulation on beaches raises a serious concern worldwide. Hence, the present study was conducted with the focus of investigating the abundance, characteristics, risk assessment, surface morphology and elemental composition of microplastics (MPs) in the beach sediments of the Thoothukudi region, situated on the south-east coast of India, Gulf of Mannar region. The MPs abundance ranged between 19 ± 18.62 and 78.55 ± 95.17 items/kg with a mean abundance of 33.82 ± 26.11 items/kg and the spatial distribution of MPs showed insignificant variation. Fragments (59.48%), 0.5-1 mm (43.66%) and blue-coloured MPs (45.61%) were highly predominant in the sediments. Attenuated total reflection - Fourier transform infrared (ATR-FTIR) spectroscopy showed the dominance of polyethylene polymers in sediments (52.26%) and their sources could be attributed to the direct inflow of sewage, recreational and fishing activities and accidental loss. The current study revealed that microplastics (< 5 mm) are ubiquitous along the Thoothukudi coast, posing a serious threat to the marine environment and marine organisms. The ecological risk assessment of MPs in sediments was calculated by adopting 3 models: the polymer hazard index (PHI), pollution load index (PLI) and potential ecological risk assessment (RI). The overall PHIsediments = 698.96 exhibited a hazard level of IV, which was mainly due to the varying abundance of polymer composition in sediments. The value of PLIsediments is 2.51, which mainly depends on the MPs abundance in sediments and yields the hazard level of I. The ecological risk posed by MPs in beach sediments along the Thoothukudi coast (RIsediments = 241.06) falls into the medium category, indicating that steps must be taken to reduce the flow of plastics through management measures such as proper wastewater treatment practices, recycling of plastic waste and proper waste disposal. Field emission scanning electron microscopy (FESEM) images revealed that MPs surfaces were strongly weathered and energy dispersive X-ray (EDX) spectroscopy spectra showed that the presence of inorganic elements associated with the surface MPs might be derived from the surrounding environment or additives in plastics. Hence, further research has to be conducted in view of studying the combined effects of MPs pollution and organic pollutants, which will provide further understanding of the contamination of MPs in the marine environment.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Polietileno/análise , Polímeros , Medição de Risco , Esgotos , Poluentes Químicos da Água/análise
10.
Mar Pollut Bull ; 180: 113742, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35635878

RESUMO

Mercury (Hg) is a global pollutant that is a major public health concern due to its mobility, stability and toxicity behavior in the environment. In this study Hg concentrations were determined in beach sediment samples (n = 43) collected from the South Durban Coast, South Africa. A human health risk assessment was also carried out to comprehend the potential health effects of incidental ingestion/direct contact with contaminated sediments in a recreational setting. Hg concentrations ranged between 0.62 and 4.88 mg kg-1 dw., exceeding all background and regulatory limits. Numerical values of calculated exposure pathways represented dermal contact with the sediments as one of the potential paths in both adults and children. Hazard Index (HI) values were found to be less than unity signifying no adverse health effects. This study validates the critical need for long-term monitoring of Hg in various scenarios in order to incorporate better public health management strategies.


Assuntos
Mercúrio , Poluentes Químicos da Água , Quimiometria , Criança , Monitoramento Ambiental , Sedimentos Geológicos/análise , Humanos , Mercúrio/análise , África do Sul , Poluentes Químicos da Água/análise
11.
Mar Pollut Bull ; 181: 113925, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35841675

RESUMO

The present study was carried out to quantify microplastic prevalence among 20 sandy beaches on the Gujarat coast. Beaches were categorised into three different classes, viz. low-impacted sites, moderately impacted sites, and highly impacted sites based on anthropogenic pressure. Microplastic (MP) (≤ 5 mm) contamination on the beaches varied with an average of 1.4 MPs/kg to 26 MPs/kg sediment. Sutrapada site-1 and Porbandar showed the highest and lowest mean abundance of microplastics, respectively, among 20 selected beaches. Out of the total assessed microplastics, threads were the maximum (89.98%), followed by the films (4.75%), fragments (3.36%) and foam (1.89%). In terms of colour and size, different microplastics were recorded in this study. The chemical composition of microplastics was identified by ATR-FTIR as polypropylene (47.5%), polyethylene (26%), and polystyrene (25%). Tourism and fishing activities are the possible sources of higher microplastic contamination at highly impacted sites.


Assuntos
Microplásticos , Poluentes Químicos da Água , Praias , Monitoramento Ambiental , Sedimentos Geológicos/química , Índia , Plásticos , Poluentes Químicos da Água/análise
12.
Environ Pollut ; 305: 119315, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35439596

RESUMO

Microplastics (MPs) and its associated organic and inorganic contaminants are one among the significant health hazards to almost all biota, including human. We investigated the polymer hazard risk and its adsorbed contaminants in MPs at six prominent beaches of Chennai on the southeast coast of India. The spatial variation of MPs during the northeast (NE) monsoon (range: 76-720 items/kg, mean: 247.4 items/kg) was higher than that during southwest (SW) monsoon (range: 84-498 items/kg, mean: 302.7 items/kg). In both the seasons, polyethylene (PE) and polypropylene (PP) were the dominant polymers and fibre was the predominant shape of MPs, likely to be derived from fishing, textile and urban activities in this region. Scanning electron microscope (SEM) images exhibited various surface weathering features including grooves, cracks, fractures, adhering particles, pits, vermiculate textures and fibre reinforcements. Energy dispersive X-ray spectrometer (EDS) results showed that MPs have adsorbed major (Si, Al, Na, Mg, Ca, Fe and Ti) and trace (Cu, Cr, Ni, Pb and Zn) metals. Though pollution load index (PLI) presented low degree of MP contamination in the beach sediments, hazardous polymers such as polyvinyl chloride (PVC), polyamide (PA) and polystyrene (PS) contributed to high polymer hazard index (PHI) and potential ecological risk index (PERI), posing very high risk to the biota. The trajectories obtained from particle-tracking coupled with hydrodynamic simulation clearly showed that 20% of MPs settled along the coast and the remaining moved towards north, alongshore and offshore (∼50 km) within 30 days, and in NE monsoon due to current reversal, the floating debris and MPs have drifted towards south, ∼40 km in 30 days, indicating the role of circulation in the fate and transport pathways of plastic debris.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Índia , Plásticos , Polímeros , Estações do Ano , Poluentes Químicos da Água/análise
13.
Mar Pollut Bull ; 183: 114024, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35999084

RESUMO

Heavy metal pollution on beaches due to enhanced human activities has received attention. This study takes four beaches in China as examples to study the characteristics of heavy metal pollution. The results show that most beach sediments have a certain degree of heavy metal accumulation as a result of human activities, except for the sediments of No. 1 beach. The beaches in order of the degree of pollution were No. 3 beach > Shilaoren beach > No. 2 beach > No. 1 beach. Three of the four studied beaches show contamination with As, Cr, Fe, Ni, Pb and Zn. Sewage outlets are the main sources of these pollutants, but the high levels of Zn and Fe are caused by coal cinder dumping at one beach, and the high levels of Ni are due to the coating of fishing boats at another beach. Heavy metal pollution occurs in areas near pollutant sources or at the high or low tide lines due to waves and tides. Heavy metals also diffuse vertically, resulting in contamination at certain depths. The distribution of heavy metals over ten years showed that most of the pollutants on cape-bay beaches are difficult to diffuse outward, which indicates that a special pollutant management plan needs to be developed for such beaches.


Assuntos
Metais Pesados , Poluentes Químicos da Água , China , Carvão Mineral , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Humanos , Chumbo , Metais Pesados/análise , Medição de Risco , Esgotos , Poluentes Químicos da Água/análise
14.
Mar Pollut Bull ; 182: 113976, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35921735

RESUMO

We investigated an unexpected microplastic (MP) leakage event that occurred along the coastline of Yantai in January 2021. Sediment samples were collected from three zones on 9 beaches. MPs were identified with an average abundance of 247.6 ±â€¯125.6 items/m2 on 7 beaches. The total amount of MPs from the leak accident was estimated to be 1.50 × 107 items (514.67 kg). The MPs were identified as polyethylene (PE), polypropylene (PP), and PP/PE blends using µ-FT-IR analysis. By utilizing a numerical model, the transmission process and potential source of MPs were demonstrated. The modeling results showed that the MPs might originate from the central and western part of the Bohai Sea and be driven to the beaches of Yantai by northwest wind and wind-induced surface current. However, due to the absence of direct evidence, the simulation results might only indicate the range of the leaking source, which was the movement trajectory of MPs.


Assuntos
Microplásticos , Poluentes Químicos da Água , Acidentes , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos/análise , Polietileno/análise , Polipropilenos/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
15.
Mar Pollut Bull ; 167: 112264, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33780756

RESUMO

Microplastic (MPs) pollution has been recognized as a serious threat to marine environment with the growing use of plastics. There is no sufficient data on the extent and characteristics of MPs pollution in the beach sediments and sand in the Atlantic Ocean. The coastal area is one of the main tourist zones in Aveiro in Portugal, thus, impacted by both tourism and maritime traffic, which are major sources of MPs. Considering this issue, 33 sediment samples were collected from the Praia da Barra beach in Aveiro. This pilot study showed that large quantities of MPs are accumulated on this beach with a median concentration of 100 MP kg-1 (15-320 MP kg-1), that is dominated by polyethylene (30%), polypropylene (27%), polystyrene (18%), nylon (12%), and polyester (6%). Size <1 mm constituted 99.5% of particles, mostly of transparent or black colors, with highest concentrations closest to the water line.


Assuntos
Microplásticos , Poluentes Químicos da Água , Oceano Atlântico , Monitoramento Ambiental , Sedimentos Geológicos , Projetos Piloto , Plásticos , Portugal , Poluentes Químicos da Água/análise
16.
Mar Pollut Bull ; 169: 112578, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34102414

RESUMO

The occurrence of microplastics (MPs) in nearshore zones of the southern Caspian coasts is well documented; however, no data are available on MP occurrence in offshore sediments. In this study, six sandy beach stations and 18 inshore-offshore stations (six transects) were surveyed. MPs were detected in all sediment samples. The mean abundances of MPs in the beach and inshore-offshore stations were 196.67 ± 11.58 and 103.15 ± 7.21 MPs/kg, respectively. Fibers constituted the most common shape of MPs. Polystyrene (PS) and polyethylene terephthalate (PET) were the major polymer types found in the beach and inshore-offshore sediments, respectively. In most transects, negative MP gradients were observed from nearshore to offshore, which showed that coastal fishing, tourism, and rivers were the main sources of MPs in this area. These results will improve our understanding on MPs pollution in the marine ecosystem. We recommend further MP studies in different parts of the Caspian Sea to develop appropriate management programs.


Assuntos
Microplásticos , Poluentes Químicos da Água , Mar Cáspio , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Poluentes Químicos da Água/análise
17.
Mar Pollut Bull ; 169: 112550, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34091249

RESUMO

The presence of microplastic particles from five different beach locations (Arabian Sea coast) in the Indian state of Karnataka was assessed. The sieving and density separation method was modified to enhance the yield of microplastics. Three different techniques were used to characterize isolated microplastics, such as optical fluorescence microscopy, Raman spectroscopy, and FESEM-EDX. Microplastic concentrations ranged from 264 ± 62 n/kg to 1002 ± 174 n/kg of dry sand in beach sediments, and the average abundance of the five beaches was 664 ± 114 n/kg. The majority of the microplastics were fragmented, <1 mm in size, white and transparent in color. FESEM images of microplastics show the roughness, cracks, mechanical and oxidative weathering, indicating their continuous exposure in the environment. EDX spectra provide the presence of various elements on the microplastic surface.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Índia , Plásticos , Poluentes Químicos da Água/análise , Tempo (Meteorologia)
18.
Mar Pollut Bull ; 172: 112904, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34469828

RESUMO

The present study was conducted to assess the distribution of plastic debris in pre- and post-cyclonic beach sediments in Silver beach, Cuddalore, southeast coast of India. The total amount of macroplastic in pre-cyclonic beach sediments was higher than that in the post-cyclonic coastal sediments (pre-cyclonic 16.1%; post-cyclonic 5.4%). The polymer varieties in pre- and post-cyclonic sediments were present in the following descending order: Pre-cyclonic sediments: polyvinyl chloride (79.06%) > polyethylene (13.9%) > nylon (6.9%); post cyclonic sediments: polypropylene (31.4%) > polyethylene (30.5%) > polystyrene (16.0) > nylon (15.5%) > polyvinyl chloride (5.1%). The different varieties of polymers with irregular shapes in the sediments are most probably introduced into the coastal environment by cyclonic floods. Wind and cyclone-induced rainfall were the driving forces for the transportation and deposition of plastic debris. The results of this study will be useful to formulate effective beach litter management policies in an attempt to develop long-term solutions.


Assuntos
Tempestades Ciclônicas , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Poluentes Químicos da Água/análise
19.
Chemosphere ; 277: 130261, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34384177

RESUMO

The study evaluated the spatial and seasonal variations of microplastic abundances in water, sediments, and commercial fishes of a semi-urban tourist impacted estuary in the Gulf of Mexico, Mexico. The prevalence of microplastics (MPs) elucidated diffuse sources namely long-range transport, domestic, agricultural, fishing, industrial and recreational activities and the local climatic conditions. Seasonally, the mean abundances of MPs in both water and sediments were high during Nortes (strong winds) followed by the dry and rainy seasons. Overall, black and blue colored MPs dominated the region and all the recovered plastics were fibers. The commercial fishes (n = 187) contained 881 MPs in their gastrointestinal tracts, suggesting that the food web of the estuary is highly prone to microplastic contamination. SEM images of extracted plastic fibers presented surface morphologies that are impacted by physical strains. Further, the elemental characterization of fibers using EDX displayed significant peaks of Al, As, Cl, Cr, Cu, Pb, and Zn that were used as additives during the production of plastics. The main types of polymers included low-density polyethylene, polyester, polypropylene, polycarbonate, rayon, polyvinyl chloride, polyacrylonitrile, polyamide, nylon and polyethylene terephthalate. MP abundances demonstrated in this study elucidate that estuaries are a major conduit for land-derived plastics to the ocean and the results will aid in implementing remedial/clean up actions of the estuary for better conservation of the ecosystem.


Assuntos
Microplásticos , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Estuários , Golfo do México , México , Plásticos , Estações do Ano , Poluentes Químicos da Água/análise
20.
Environ Sci Pollut Res Int ; 28(26): 34259-34268, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33394425

RESUMO

Microplastic (MP) pollution is an emerging environmental problem, particularly in the marine environment, and nations are concerned about this issue. In this study, an attempt has been made to investigate the vertical distribution of MPs present in the beach sediments around the Ras Rakan Island of Qatar. Sampling was conducted at 9 locations, vertically to a depth of 30 cm with an interval of 5 cm. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy was used to chemically identify the subsets of MPs as polyethylene (PE), polypropylene (PP), polyamide (PA), polyethylene terephthalate (PET), polyvinyl chloride (PVC), and polystyrene (EPS). The counts of MPs were found to be higher in the western and northern parts of the island. The vertical distribution of MPs ranged from 0 to 665 particles/kilogram with maximum abundance at the surface layer (0-5 cm). Pellets were the dominant type of MPs in the surface sediments, whereas fibers were dominant in the bottom sediments. The prevailing winds, waves, tides, and currents are the forces responsible for the distribution and transport of MPs from offshore to the island and further to vertical re-distribution as time progresses. The level of MP pollution along the coast of Ras Rakan Island was higher than that found on the coast of mainland Qatar. Thus, informing that remote islands should also be considered for MP pollution monitoring programs to assess the risk associated with MP on the biota.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Catar , Poluentes Químicos da Água/análise
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