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Anthropoquinas: First description of plastics and other man-made materials in recently formed coastal sedimentary rocks in the southern hemisphere Full text
2020
Fernandino, Gerson | Elliff, Carla I. | Francischini, Heitor | Dentzien-Dias, Paula
Plastic, as a “flagship species”, represents how deeply humans impact the environment. Although scarce, the presence of plastic and other anthropogenic materials in rocks has already been reported in the literature, however, so far, not in the Southern Hemisphere. Thus, the objective of the present study was to report and describe samples of sedimentary rocks containing anthropogenic items cemented with biogenic and siliciclastic material – anthropoquinas – and to discuss implications to the establishment of the Anthropocene and geodiversity conservation. Six samples of anthropoquinas were evaluated, presenting different technofossils (metal bottle caps, ship nail, plastic earring and plastic fragment) and composition (lithic and biogenic fragments). Energy Dispersive X-ray Spectroscopy was conducted on two samples, reflecting differences regarding their genesis. The description of these rocks is concerning and reflects how deeply human behavior influences various natural compartments. Therefore, studies on the effects of marine litter on geodiversity are strongly encouraged.
Show more [+] Less [-]Barnacles as potential bioindicator of microplastic pollution in Hong Kong Full text
2020
Xu, X. Y. | Wong, C.Y. | Tam, N.F.Y. | Liu, H.M. | Cheung, S.G.
Microplastic (MP) pollution is an emerging problem in the marine environment and the assessment of the presence and abundance of microplastics in wild organisms is essential for risk assessment. The occurrence of microplastics in four species of barnacles at 30 sites in Hong Kong waters was investigated. The median number of microplastics ranged between 0 and 8.63 particles g⁻¹ wet weight, or 0 and 1.9 particles individual⁻¹, with fibers being the most abundant type of microplastics. The chemical composition of 152 pieces out of 606 potential microplastics was analyzed using micro-Fourier Transform Infrared Spectroscopy (μ-FTIR). Fifty-two of them were synthetic polymers, 95 natural cotton fibers and five unknowns. Eight types of polymer were identified with cellophane being the most abundant (58%). Correlation analysis was conducted between the abundance of MPs in sediments obtained in our previous study and that in individual barnacle species in this study, and a positive correlation was established for the barnacle Amphibalanus amphitrite, highlighting the potential of using this species as a bioindicator of microplastics.
Show more [+] Less [-]Contaminants, mutagenicity and toxicity in the surface waters of Kyiv, Ukraine Full text
2020
Ho, Kay T. | Konovets, Igor M. | Terletskaya, Anna V. | Milyukin, Mykhailo V. | Lyashenko, Artem V. | Shitikova, Larisa I. | Shevchuk, Lyudmila I. | Afanasyev, Sergey A. | Krot, Yurii G. | Zorina-Sakharova, Kateryna Ye | Goncharuk, Vladislav V. | Skrynnyk, Maksym M. | Cashman, Michaela A. | Burgess, Robert M.
Kyiv is Ukraine's capital and largest city. Home to 3 million people, this area has a rich history of agriculture and industry. The Dnieper River is Ukraine's largest river and it passes through the center of Kyiv. Little information on emerging and legacy compounds or their toxicity in the Dnieper River exists. For this investigation, water was sampled for PAHs, PCBs, metals and emerging contaminants including pharmaceuticals and personal care products. The effects of surface waters in the Dnieper were evaluated using the Ames, chronic and acute daphnia, and a ciliate (Colpoda stennii) assays. Concentrations of legacy and emerging contaminants were found in seven stations near the municipal water treatment plant (MWTP) and receiving waters. The MWTP appeared to remove some of the emerging contaminants, however the legacy compounds (PCBs and PAHs) were not affected by the MWTP and appeared to be more wide-spread indicating a number of sources to the Dnieper River. Acute and chronic toxicity were associated with the influent and effluent of the MWTP, however mutagenicity was noted in surface waters throughout the Dnieper River including upstream of the MWTP. This study provides the first snapshot of possible human health and ecological risks associated with surface waters of the Dnieper. More research on seasonal changes and sources of toxicity, mutagenicity and contaminants would aid in completing a more comprehensive risk assessment of surface waters of the Dnieper River.
Show more [+] Less [-]Plastic intake does not depend on fish eating habits: Identification of microplastics in the stomach contents of fish on an urban beach in Brazil Full text
2020
Dantas, Natália C.F.M. | Duarte, Oscar S. | Ferreira, Wellington C. | Ayala, Alejandro P. | Rezende, Carla F. | Feitosa, Caroline V.
This study aims to identify, classify, quantify the ingested microplastic by marine teleost fish, in order to analyze the relationship between microplastic and trophic guilds. Food items of 214 individuals of Opisthonema oglinum, Bagre marinus, Cathorops spixii, Sciades herzbergii, Chloroscombrus chrysurus, Conodon nobilis, Haemulopsis corvinaeformis were analyzed. The species were classified according to their trophic guilds (zoobenthivorous or opportunistic/omnivorous). All species ingested microplastic and contamination occurred independently of the trophic guild. Of the sampled fish, 55% were contaminated by microplastic. The most consumed categories were blue (28%) and transparent filaments (20%). Raman spectroscopy measurements detected that most sampled filament corresponds to blue synthetic fiber (polyester). This study can contribute by filling gaps in knowledge regarding sandy beach impacts, which are environments so highly threatened by human activities around the world and are neglected in terms of use and conservation plans.
Show more [+] Less [-]Quantifying microplastic translocation from feed to the fillet in European sea bass Dicentrarchus labrax Full text
2020
Zeytin, Sinem | Wagner, Gretchen | Mackay-Roberts, Nick | Gerdts, Gunnar | Schuirmann, Erwin | Klockmann, Sven | Slater, Matthew
Quantifying microplastic translocation from feed to the fillet in European sea bass Dicentrarchus labrax Full text
2020
Zeytin, Sinem | Wagner, Gretchen | Mackay-Roberts, Nick | Gerdts, Gunnar | Schuirmann, Erwin | Klockmann, Sven | Slater, Matthew
Uptake of microplastic (MP) particles has been detected in a large number of marine organisms, and humans may consequently be exposed to high MP levels in consumed seafood. Yet there remains a dearth of knowledge regarding uptake into commercially important finfish and tissues (fillets) most commonly consumed by humans. The current study detected translocation of MP into the fillet of European seabass (Dicentrarchus labrax) juveniles fed with a diet containing fluorescent MP particles (1–5 μm) for 16 weeks. Results indicate MP translocation to fillet, with mean fillet MP content calculated as 0.36 ± 0.29 MP/g⁻¹ fillet on the basis of manual fluorescent microscopy counts and 0.15 ± 0.28 MP/g⁻¹ fillet on the basis of automated fluorescent microscopy counts. The retention/translocation rate is estimated at approximately 1 MP reaching the fillet for every 1.87 × 10⁷ ingested in the experimental diet. This study presents first data of MP translocation from feed to the tissue fillet in European seabass and aids future examinations of the MP load in seafood for human consumption.
Show more [+] Less [-]Quantifying microplastic translocation from feed to the fillet in European sea bass Dicentrarchus labrax Full text
2020
Zeytin, Sinem | Wagner, Gretchen | Mackay-Roberts, Nick | Gerdts, Gunnar | Schuirmann, Erwin | Klockmann, Sven | Slater, Matthew James
Risk assessment of Arctic aquatic species using ecotoxicological biomarkers and Bayesian network Full text
2020
Fahd, Faisal | Veitch, Brian | K̲h̲ān, Faiṣal
The risk to Arctic aquatic species due to accidental oil spills is not well studied. One of the key reasons for this limitation is the lack of understanding of the dose-response relations for the species in the Arctic region. The present study addresses this knowledge gap. It proposes a new approach to develop dose-response curves for Arctic aquatic species. The application of the approach is demonstrated using the estimation of mortality risk in Boreogadus saida (polar cod) due to exposure from polycyclic aromatic hydrocarbons (PAH).The proposed approach considers the toxicity mechanism in Arctic species (i.e. polar cod) and regional environmental factors, and models these as a belief-based Bayesian Network (BN). The BN model integrates diverse ecotoxicology biomarker data types and predicts the cell death probability due to exposure to a toxicant (PAH in crude oil). The input data and results from the model were verified using data available in the literature. Seasonal sea ice played a major role in containing PAH exposure and subsequent risk to polar cod. However, the physiological factors, such as presence of higher Phase II activity, and higher oxyradical scavenging ability, had greater impact on PAH risk mitigation.
Show more [+] Less [-]Assessment of PCDD/Fs, dioxin-like PCBs and PBDEs in Mediterranean striped dolphins Full text
2020
Capanni, Francesca | Muñoz-Arnanz, Juan | Marsili, Letizia | Fossi, M Cristina | Jiménez, Begoña
Bio-accumulation of high levels of persistent organic pollutants represent a serious conservation concern for Mediterranean marine odontocetes. In this study, blubber samples from 10 striped dolphins (Stenella coeruleoalba) stranded along the Italian coasts during 2015–2016 were analyzed. All specimens showed dl-PCBs > PBDEs ≫ PCDD/Fs. Median concentrations were 1820 ng/g l.w., 456 ng/g l.w. and 23.9 pg/g l.w., respectively. dl-PCBs accounted for 93.3% of total TEQs. PBDE concentrations suggest that the Mediterranean basin may be considered a hotspot for organobromine compounds. OCDD did not represent the greatest contributor to PCDD/Fs profile, most likely due to a change in dioxin environmental sources in the last two-three decades. Despite international regulations, the present study emphasized that POP exposure levels in Mediterranean striped dolphins have not declined significantly in recent years. Toxicological and risk assessment studies on this sentinel species may provide an early indication of potential adverse health effects on Mediterranean ecosystems.
Show more [+] Less [-]Vertical distribution of microplastics in bay sediment reflecting effects of sedimentation dynamics and anthropogenic activities Full text
2020
Zheng, Yifan | Li, Jingxi | Cao, Wei | Jiang, Fenghua | Zhao, Chang | Ding, Haibing | Wang, Menghui | Gao, Fenglei | Sun, Chengjun
Microplastics are ubiquitous in our environment, yet we have little knowledge on their accumulation profile and changing trend. In this study, we selected the semi-enclosed Jiaozhou Bay as the research area to study the vertical distribution characteristics of microplastic in the sediment and analyzed factors that might affect this distribution pattern. We found six different polymer types and the microplastic abundance ranged between 2.5 items/kg d.w.-27.5 items/kg d.w.. Microplastic abundance was very low in deep sediment and generally showed a decreasing trend from the surface down with some shifts at different depth at certain sites. Based on our data, the total microplastics in the sediment were estimated to reach 3.71 tons in Jiaozhou Bay. This study shows that the vertical microplastic abundance profile in the sediment can not only show the microplastics pollution level but also reflect environmental factors and anthropogenic impacts.
Show more [+] Less [-]Modelling bivalve culture - Eutrophication interactions in shallow coastal ecosystems Full text
2020
Lavaud, Romain | Guyondet, T. | Filgueira, Ramón | Tremblay, Réjean | Comeau, Luc A.
Assessing the carrying capacity of ecosystems is crucial to the selection of suitable and sustainable locations for aquaculture farms. In Malpeque Bay (PEI, Canada), the potential expansion of mussel farms has driven a series of numerical modelling studies. We coupled sub-models for sea lettuce, wild and cultured oysters and wild softshell clams to an existing ecosystem model to better understand nutrient dynamics and the carrying capacity of Malpeque Bay. Simulations suggested that competition for nutrients between phytoplankton and sea lettuce and filtration by cultured bivalves predominantly mitigate eutrophication effects. The addition of sea lettuce reduced mussel growth by 2% on average and up to 9% near eutrophic estuaries favouring macroalgae growth. Projected new mussel farms reduced current mussel growth by 2% also, suggesting that the carrying capacity of the bay may not be reached yet. Both current and projected aquaculture activities seemed to have limited effects on natural bivalve growth.
Show more [+] Less [-]Temporal trends in aluminum smelter-derived polycyclic aromatic hydrocarbons in outmigrant juvenile Chinook salmon from Kitimat, British Columbia, Canada Full text
2020
Anulacion, Bernadita F. | Ylitalo, Gina M. | Sol, Sean Y. | da Silva, Denis A.M. | Lomax, Daniel P. | Johnson, Lyndal L.
Aluminum smelter-derived polycyclic aromatic hydrocarbons (PAHs) in outmigrant juvenile Chinook salmon were evaluated in Kitimat Arm, British Columbia, Canada from 2000 to 2004, and in 2015. Decades of continual smelter operations by Rio Tinto resulted in PAH contamination of marine sediments at levels associated with adverse effects in juvenile salmon. Recently, smelter operations have undergone process changes to reduce PAH input to the environment. The PAH concentrations in juvenile Chinook salmon observed in 2000 to 2004, at sites nearest the smelter were comparable to salmon in other urban areas where reduced disease resistance was observed; the levels were lower in 2015 than 2000–2004 suggesting that the recent process changes were effective. Further, these data establish a benchmark for assessing any future changes affecting PAH input and the potential risks to the receiving environment.
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