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Severe contamination and time trend of legacy and alternative plasticizers in a highly industrialized lake associated with regulations and coastal development Полный текст
2021
Kim, Youngju | Kim, Soy | Liao, Chunyang | Moon, Hyo-Bang
Few studies have been conducted on aquatic contamination by alternative plasticizers. Phthalates and novel plasticizers were measured in sediments from a highly industrialized lake to assess occurrence, sources, time trends, and ecological risks. Legacy and alternative plasticizers were detected in all sediments. Di(2-ethylhexyl) phthalate (DEHP) was a predominant plasticizer, indicating its popular industrial consumption for the last two decades. Predominant novel plasticizers were changed over time. The highest sedimentary DEHP level was recorded on the global scale. Legacy and alternative plasticizers in creek sediments significantly increased from 2008 to 2016, while those from inshore and offshore regions of the lake significantly decreased in association with a dilution effect caused by the operation of a tidal power plant. Concentration ratios of alternative plasticizers to DEHP increased for the last decade, implying a shift in consumption of plasticizers. Sedimentary DEHP concentrations in creeks exceeded almost all threshold values associated with ecological risks.
Показать больше [+] Меньше [-]Is the weight of plastic litter correlated with vegetal wrack? A case study from a Central Italian beach Полный текст
2021
Cesarini, Giulia | Cera, Alessandra | Battisti, Corrado | Taurozzi, Davide | Scalici, Massimiliano
This study analyzes the occurrence and distribution of plastic litter and the entrapment of plastic by wrack beached on a natural reserve. Large microplastics (2.5 - 5 mm) were the most abundant plastic size category detected. The main color and shape were white and fragment, respectively. The plastics entrapped by egagropiles were mainly transparent fibers. We analyzed the correlation between the weights of plastic litter and vegetal wrack in two transects, selected for their different environmental characteristics. The transect closer to a breakwater showed a significant positive correlation between the weights of plastics and wrack, while the other transect suggested a casual pattern of plastic deposition on the beach. Further research is suggested to focus on the role of breakwaters in altering marine currents and enhancing plastic beaching.
Показать больше [+] Меньше [-]Utilizing benthic foraminifera to explore the environmental condition of the Laizhou Bay (Bohai Sea, China) Полный текст
2021
Donnici, Sandra | Serandrei-Barbero, Rossana | Gao, Xuelu | Tang, Cheng | Tosi, Luigi
Through the analysis of benthic foraminifera in the soft bottom sediments of the Laizhou Bay – Yellow River Delta system, this study characterized the foraminiferal biotopes and explored the possibility of obtaining an index of ecological quality comparable with other estuarine and coastal environments of the world. Five foraminiferal biotopes have been identified and their distribution patterns highlight the ecological stress from the marine-fluvial water mixing and pollution. The foraminiferal species were analyzed as a function of organic carbon gradients, and the main species were assigned to four ecological groups based on their sensitivity/tolerance towards an increasing stress gradient. Finally, the relative proportions of the species assigned to the four different ecological groups were used for the definition of a marine biotic index based on foraminifera, i.e. the Foram-AMBI, and thus the assessment of the ecological quality status of marine soft-bottom habitats.
Показать больше [+] Меньше [-]Impacts of Personalized Sensor Feedback Regarding Exposure to Environmental Stressors Полный текст
2021
Becker, Anna Maria | Marquart, Heike | Masson, Torsten | Helbig, Carolin | Schlink, Uwe
Feedback on personal exposure to air pollution, noise or extreme temperatures through wearable sensors or sensors installed at home or in the workplace can offer information that might motivate behaviours to mitigate exposure. As personal measurement devices are becoming increasingly accessible, it is important to evaluate the effects of such sensors on human perception and behaviour. We conducted a systematic literature research and identified 33 studies, analysing the effects of personal feedback on air pollution, noise and temperatures. Feedback was given through reports including different forms of visualization, in-person or over the telephone, or directly on the sensor or through a phone app. The exposure feedback led to behaviour changes particularly for noise and temperature feedback while findings on behaviour adaptation to avoid air pollution were mixed. Most studies reported increased awareness and knowledge from receiving exposure feedback. Many participants in studies on air pollution reported low levels of self-efficacy regarding exposure mitigation. For a better understanding of the effects of personal exposure feedback, more studies are required, particularly providing feedback from wearable sensors measuring outdoor air pollution, noise and temperature.
Показать больше [+] Меньше [-]A Review of Immobilisation-Based Remediation of Per- and Poly-Fluoroalkyl Substances (PFAS) in Soils Полный текст
2021
Sleep, Julie A. | Juhasz, Albert L.
PURPOSE OF REVIEW: This review provides an overview of the latest developments in immobilisation of per- and poly-fluoroalkyl substances (PFAS) for soil remediation. It examines the efficacy of a range of amendments, including those with binding agents, along with a discussion of immobilisation mechanisms and post-immobilisation assessment needs. RECENT FINDINGS: Researchers have recently applied a variety of soil amendments to soil for PFAS immobilisation. Efficacy of these has varied widely, both between amendment and soil types and for individual PFAS molecules present in contaminated soils. Activated carbon based amendments, including composite amendments exhibit the highest efficacies of the examined studies. Immobilisation of PFAS is complex, with efficacy of immobilisation varying with soil properties including pH, clay and organic matter content, amendment properties, and molecular properties of the individual PFAS. Optimal remediation strategies need to be adjusted accordingly to site specific soil properties and contamination profiles. Additionally, bioavailability testing needs to supplement standard leaching approaches to determine effectiveness of PFAS soil immobilisation strategies.
Показать больше [+] Меньше [-]Intra and extracellular effects of benzo [α] pyrene on liver, gill and blood of Caspian White fish (Rutilus frissi kutum): Cyto-genotoxicity and histopathology approach Полный текст
2021
Esmaeilbeigi, Milad | Kalbassi, Mohammad Reza | Seyedi, Javad | Tayemeh, Mohammad Behzadi | Moghaddam, Jamshid Amiri
Southern parts of the Caspian Sea have been faced with a diverse range of oil pollutants. Therefore, this study was designed to evaluate the effects of relevant environmental concentrations of benzo[α]pyrene (BαP) on liver, gill, and blood of Caspian White fish. To this end, 150 fingerling fish (6.5 ± 0.8 g) were exposed to under, near and over environmental concentrations of BαP (i.e. 50, 100, and 200 ppb, respectively) and two control groups for 21 days. Following exposure to BαP, generally, DNA damage increased in the liver and gill cells as well as the frequency of micro- and bi-nucleated erythrocytes in a time and concentration-dependent pattern. In addition, the liver and gill tissues displayed several histopathological lesions. Together, the findings are warning the health status of the Caspian Sea due to an ever-increasing concentration of BαP through using Caspian White fish as an ecological model.
Показать больше [+] Меньше [-]Sub-lethal combined effects of illicit drug and decreased pH on marine mussels: A short-time exposure to crack cocaine in CO2 enrichment scenarios Полный текст
2021
da Silva Souza, Lorena | Bonnail, Estefanía | Maranho, Luciane Alves | Pusceddu, Fabio Hermes | Cortez, Fernando Sanzi | Cesar, Augusto | Ribeiro, Daniel Araki | Riba, Inmaculada | de Souza Abessa, Denis M. | DelValls, Ángel | Pereira, Camilo Dias Seabra
The increasing CO₂-concentrations in the atmosphere promote ocean acidification. Seawater chemistry changes interact with contaminants, such as illicit drugs in the coastal zones. This work evaluates impacts of pH decrease and crack-cocaine exposure on the commercial mussel Perna perna through biomarker responses (lysosomal membrane stability, lipid peroxidation, and DNA strand breaks). The organisms were exposed to different crack-cocaine concentrations (0.5, 5.0, and 50 μg L⁻¹) combined with different pH values (8.3, 8.0, 7.5, 7.0, 6.5, and 6.0) for 96 h. Crack-cocaine in the different acidification scenarios triggered cyto-genotoxicity, which affected the overall health of mussels exposed to cocaine environmentally relevant concentration. This study produced the first data on biomarker responses associated with CO₂-induced acidification and illicit drugs (crack-cocaine) in marine organisms.
Показать больше [+] Меньше [-]Modeling the relationship between emerging and persistent organic contaminants in water, sediment and oysters from a temperate lagoon Полный текст
2021
Stoĭchev, Teodor | Marques, António | Almeida, Cristina Marisa R.
The concentrations of emerging and persistent organic contaminants (EPOC) in oysters (CO) from Aveiro Lagoon are represented as a function of their concentrations in water (CW) and sediment (CS) using linear and generalized additive models (LM, GAM). Additionally, four sampling seasons, octanol/water partition coefficients (K) and type of EPOC (pyrethroids, flame-retardants, musks, UV filters, polycyclic aromatic hydrocarbons, others) are included in the models. The probabilities of detection of EPOC in water, sediment and oysters are analyzed by GAM. The behavior of contaminants in water is determined by K with a clear seasonal trend. Sediments are reservoirs for hydrophobic compounds with less seasonal variation. Seasonal changes are found for CO, the last being determined additively both by CW and hydrophobicity from one side and by CS and type of contaminants from the other side. The seasonal change of EPOC concentration in water, sediment and oysters is specific for each contaminant type.
Показать больше [+] Меньше [-]Marine litter pollution in mangrove forests from Providencia and Santa Catalina islands, after Hurricane IOTA path in the Colombian Caribbean Полный текст
2021
Garcés-Ordóñez, Ostin | Saldarriaga-Vélez, Juan F. | Espinosa-Díaz, Luisa F.
Marine litter in mangroves comes mainly from poor waste management practices and its abundance is increased by natural catastrophes occurrence that affects coastal settlements, as occurred in November-2020, when two hurricanes (ETA and IOTA) destroyed homes and deposited litters in mangroves of the Providencia and Santa Catalina islands, in the Colombian Caribbean. This study aims to assess the litter pollution in mangrove forests of these islands after Hurricane IOTA. Litter pollution was high in mangroves near urban areas and low in mangroves with little urban influence. In three mangrove sectors with high pollution, litter densities of 0.4–1.4 items m⁻² and masses of 0.1–1.2 kg m⁻² were determined; the majority were megalitter (sizes >1 m). Plastics were the most abundant (>60%). Local community is aware of the litter pollution problem and their participation in scientific research and mangroves recovery is key to understanding the impacts of natural and anthropogenic events and for ecosystem conservation.
Показать больше [+] Меньше [-]Detecting stranded macro-litter categories on drone orthophoto by a multi-class Neural Network Полный текст
2021
Pinto, Luis | Andriolo, Umberto | Gonçalves, Gil
The use of Unmanned Aerial Systems (UAS, aka drones) images for mapping macro-litter in the environment have been exponentially increasing in the recent years. In this work, we developed a multi-class Neural Network (NN) to automatically identify stranded plastic litter categories on an UAS-derived orthophoto.The best results were assessed for items that did not have substantial intra-class colour variability, such as octopus pots and fishing ropes (F-score = 61%, on average). Instead, performance was poor (37%) for plastic bottles and fragments, due to their changing intra-class colours. On average, the performance improved 24% when the binary detection (litter/non-litter, F-Score = 73%) was considered, however this approach did not discriminate the litter categories.This work gives a new perspective for the automated litter detection on drone images, suggesting that colour-based approach can be used to improve the categorization of stranded litter on UAS orthophoto.
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