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Abundance, composition, and potential intake of microplastics in canned fish Полный текст
2020
Akhbarizadeh, Razegheh | Dobaradaran, Sina | Nabipour, Iraj | Tajbakhsh, Saeed | Darabi, Amir Hossein | Spitz, Jörg
The existence of microplastics (MPs) in canned fish (tuna and mackerel) samples was investigated and their composition, possible sources and potential intake were assessed. Light and fluorescence microscopy were used for the quantification of potential MPs. Furthermore, micro-Raman microscopy, and scanning electron microscopy coupled with an energy dispersive X-ray were used to identify the polymer types and composition of MPs. The results showed that 80% of samples had at least one plastic particle and fibers were the most abundant shapes of MPs. Moreover, polyethylene terephthalate (32.8%) was the most common polymer type in canned fish samples. The fish, food additives, and contact materials during the cleaning and canning process are possible sources of MPs. Human intake estimation of MPs showed the possibility of plastics absorption by humans who consume canned fish several times/week. Hence, the results of this study showed the importance of MPs' guidelines for food safety and hygiene.
Показать больше [+] Меньше [-]Estimation of measurement uncertainty including surrogate recoveries in the study of polycyclic aromatic hydrocarbons in marine sediments Полный текст
2020
Shaw, David G. | Blanchard, Arny L.
We examine the use of surrogates in the measurement of concentrations of polycyclic aromatic hydrocarbons (PAH) in marine sediment, consider shortcomings of current interpretations of the results from this widely used approach, and propose an alternative data treatment. We focus on the current common practice of accepting all data within a predefined range of acceptable recoveries as equally valid and propose treating surrogate recovery data as one component of measurement uncertainty. Our analysis leads us to conclude that the more uniform surrogate recoveries are, the more justified the assumption that they reveal measurement bias and appropriately can be used as corrections; but that the less uniform recoveries are, the greater the need to treat them as a source of measurement uncertainty. We recognize that acceptance of the ideas presented here will require much thought and refinement by the environmental analytical community. We welcome a thorough discussion.
Показать больше [+] Меньше [-]Carbapenem resistant Enterobacteriaceae from port areas in São Paulo State (Brazil): Isolation and molecular characterization Полный текст
2020
Andrade, Vanessa Costa | Caetano, Tânia | Mendo, Sónia | Oliveira, Ana Júlia Fernandes Cardoso de
Coastal areas with important economic activities have high levels of contamination by metals, pathogenic bacteria, among other contaminants. The emergence of antibiotic-resistant bacteria is a global problem of public health. Carbapenem resistant Enterobacteriaceae (CRE) are a serious threat. The occurrence of carbapenem resistant bacteria was investigated in waters and sediments of a Brazilian coastal area, characterized by high levels of contamination. The samples of water and sediment were collected in two areas of the coast of São Paulo (Brazil). The study involved the characterization of the molecular mechanisms associated with the carbapenem resistance phenotype. No genes were detected for β-lactamases but the absence and/or presence of mutations in outer membrane proteins (OMPs) may justify the detected phenotype. The presented results show the need for further studies that allow a review of the current legislation and the importance of the reevaluation of monitoring policies of these environments.
Показать больше [+] Меньше [-]Limited ingestion, rapid egestion and no detectable impacts of microbeads on the moon jellyfish, Aurelia aurita Полный текст
2020
Sucharitakul, Phuping | Pitt, Kylie A. | Welsh, David T.
Jellyfish are voracious planktonic predators that may be susceptible to ingesting microplastics. We measured rates of ingestion and egestion of microbeads by Aurelia aurita (Scyphozoa) and evaluated whether ingesting microbeads affected metabolism or gut epithelia. Ingestion rates were measured by exposing medusae to microbeads and randomly sampling them 6 times over a 32 h period to determine the number of microbeads in their tissues. Egestion rates were measured by exposing medusae to microbeads for 1 h before transferring them to kreisels without microbeads and sampling them 6 times over 8 h. Respiration rates of medusae were determined using incubations and potential damage to gut epithelia was evaluated using histopathology. Medusae ingested few microbeads and egested them within 8 h. Microbeads had no effect on respiration and the histology. We concluded that the medusae may recognise microbeads as non-food particles and that their ingestion caused undetectable physiological and histological harm.
Показать больше [+] Меньше [-]Dehalogenase-producing halophiles and their potential role in bioremediation Полный текст
2020
Oyewusi, Habeebat Adekilekun | Wahab, Roswanira Abdul | Huyop, Fahrul
This review aims to briefly describe the potential role of dehalogenase-producing halophilic bacteria in decontamination of organohalide pollutants. Hypersaline habitats pose challenges to life because of low water activity (water content) and is considered as the largest and ultimate sink for pollutants due to naturally and anthropogenic activities in which a substantial amount of ecological contaminants are organohalides. Several such environments appear to host and support substantial diversity of extremely halophilic and halotolerant bacteria as well as halophilic archaea. Biodegradation of several toxic inorganic and organic compounds in both aerobic and anaerobic conditions are carried out by halophilic microbes. Therefore, remediation of polluted marine/hypersaline environments are the main scorching issues in the field of biotechnology. Although many microbial species are reported as effective pollutants degrader, but little has been isolated from marine/hypersaline environments. Therefore, more novel microbial species with dehalogenase-producing ability are still desired.
Показать больше [+] Меньше [-]Ostreopsis lenticularis Y. Fukuyo (Dinophyceae, Gonyaulacales) from the South Atlantic Ocean: morphological and molecular characterization Полный текст
2020
Borsato, Geovanna Theobald | Salgueiro, Fabiano | da Silva, Cristhian Gomes Tavares | Menezes-Salgueiro, Adriana D. | Nascimento, Silvia M.
Ostreopsis is a benthic dinoflagellate genus comprising eleven species including seven that are toxigenic. Ostreopsis lenticularis was first described from French Polynesia and is widely distributed in many insular locations from the Pacific Ocean. The current study presents morphological and molecular evidence of the presence of O. lenticularis at the Fernando de Noronha Archipelago, South Atlantic. Light microscopy and scanning electron microscopy of field cells showed morphological features in agreement with the description of O. lenticularis. Cells were broadly oval, 66.0–117.5 μm in dorso-ventral diameter, 50.0–92.5 μm in width, with thecal plates presenting two kinds of pores. Phylogenetic analyses based on LSU (D1-D3) and ITS sequences from field cells from Fernando de Noronha clustered with O. lenticularis sequences from elsewhere. The species was present in low to high abundances. The current study expands the distribution of O. lenticularis to Fernando de Noronha Archipelago in the South Atlantic Ocean.
Показать больше [+] Меньше [-]Persistent organic pollutants (POPs) and personal care products (PCPs) in the surface sediments of a large tropical bay (Todos os Santos Bay, Brazil) Полный текст
2020
Sotão Neto, Basílio M.T. | Combi, Tatiane | Taniguchi, Satie | Albergaria-Barbosa, Ana C.R. | Ramos, Raissa B. | Figueira, Rubens Cesar Lopes | Montone, Rosalinda C.
The occurrence and spatial distribution of persistent organic pollutants (POPs) and personal care products (PCPs) were investigated in surface sediments of Todos os Santos Bay. Samples were Soxhlet-extracted and analyzed by gas chromatography coupled with tandem mass spectrometry. Quantification limits (QL) ranged from 0.0025 ng g⁻¹ for POPs to 0.25 ng g⁻¹ for PCPs. Of the POPs studied, only PCBs and DDTs were detectable, with concentrations ranging from <QL to 4.66 ng g⁻¹, with increased concentrations near urban and industrial areas. PCPs ranged from <QL to 27.5 ng g⁻¹ and presented a homogeneous spatial distribution, probably related to the continuous inputs of these compounds from diffuse sources. Mean contaminant inventories ranged from 0.33 ± 0.23 ng cm⁻² for DDTs to 8.3 ± 8.4 ng cm⁻² for fragrances. To the best of our knowledge, this is the first study on the occurrence of UV filters in sediments from Brazilian coastal environments.
Показать больше [+] Меньше [-]The challenges of microbial source tracking at urban beaches for Quantitative Microbial Risk Assessment (QMRA) Полный текст
2020
Zimmer-Faust, Amity G. | Steele, Joshua A. | Griffith, John F. | Schiff, Ken
Urban beaches are frequently impacted from multiple sources of fecal contamination. This along with high beach usage underscores the importance of appropriate management that protects swimmer health. The USEPA has enabled the use of QMRA as a tool for quantifying swimmer health risk and setting site-specific water quality objectives. This study illustrates the challenges associated with human and non-human source identification and how these challenges influence the decision of whether QMRA at typical urban beaches for water quality management is appropriate. In this study, a similar and correlated spatial relationship with elevated Enterococcus and avian-specific markers was observed, suggesting shorebirds as a primary source of FIB. However, human-associated markers were also detected frequently but at low concentrations. Ultimately, a QMRA was not conducted because pathogen loading from potential human sources could not be confidently quantified, having consequences for health risk in receiving waters where recreational contact occurs.
Показать больше [+] Меньше [-]Low densities of macroplastic debris in the Pitcairn Islands Marine Reserve Полный текст
2020
Ryan, Peter G. | Schofield, Andy
Beaches on Henderson Island, one of the Pitcairn Islands in the central South Pacific, have been reported to have some of the highest standing stocks of stranded plastic recorded. Surveys of floating debris at sea show that this is not related to high densities of plastic in the area. Only 19 macroplastic items were observed during 905 km of at-sea transects (0.5 items·km⁻²; 135 g·km⁻²). This low density confirms previous microplastic surveys which show that the Pitcairn group lies west of the South Pacific Gyre. Plastic loads on beaches at other islands in the Pitcairn group are not exceptional. The east coast of Henderson Island appears to be particularly effective at accumulating drifting debris, but many small plastic fragments on these beaches probably result from degradation in situ, so removing macroplastics will reduce the formation of microplastics.
Показать больше [+] Меньше [-]World record extreme sea surface temperatures in the northwestern Arabian/Persian Gulf verified by in situ measurements Полный текст
2020
The Arabian or Persian Gulf is recognized as one of the warmest estuaries globally. The sea surface temperature (SST) has been utilized in several studies to gauge the global warming associated with climate change. In the current investigation we present detailed in situ SST measurements for five consecutive years (2016, 2017, 2018, 2019, 2020) in the northwest of the Gulf, specifically in Kuwait Bay. Results of data analyses were compared with the historical records for the region, revealing that the SST reached an extreme level never previously recorded either in the Gulf. The extreme SST in Kuwait Bay reached 37.6 °C, recorded by the offshore station KISR01 located in the middle of the Bay. The event was associated with heatwave, neap tides, and an extended period of Kous winds which are characterized by high humidity levels and accompanied by large-scale intermittent fish kill incidents that extended the full length of the Kuwait coastline. Several fish kill incidents were reported also at the northern edge of the Gulf along Shatt Al Arab stretch in Iraq. The species found dead during the incident varied considerably, unlike those found in the frequent summer incidents. The records presented in this study may provide evidence to the effects of global warming, aid further research, and encourage the concerned international government bodies to deliver urgent environmental policies.
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