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The application of quantitative microbial risk assessment to natural recreational waters: A review
2019
Federigi, Ileana | Verani, Marco | Donzelli, Gabriele | Cioni, Lorenzo | Carducci, Annalaura
This review examines the aims of and approaches to the Quantitative Microbial Risk Assessment (QMRA) of untreated recreational waters. The literature search was conducted on four databases and yielded 54 papers, which were analyzed on a quantitative (time-trend, geographical distribution, water type) and qualitative (aims, source of microbial data, pathogens and their measurement or estimation, ways to address variability and uncertainty, sensitivity analysis) basis. In addition, the parameters, implications, and limitations were discussed for each QMRA step. Since 2003, the number of papers has greatly increased, highlighting the importance of QMRA for the risk management of recreational waters. Nevertheless, QMRA still exhibits critical issues, above all regarding contamination data and dose-response relationships. To our knowledge, this is the first review to give a wide panoramic view on QMRA in relation to recreational exposure to untreated waters. This could be useful in identifying the current knowledge gaps and research needs.
Show more [+] Less [-]Distribution and pollution assessment of heavy metals in the intertidal zone environments of typical sea areas in China
2019
Zhao, Mengwei | Wang, Enkang | Xia, Peng | Feng, Aiping | Ji, Yuan | Sun, Yonggen
The heavy metals (Cu, Cr, Zn, Cd, Pb) were analysed for 217 surface sediment samples collected across 14 typical intertidal zone areas in China. The data reveals the heavy metals spatial distribution patterns and correlations among their concentrations. Cu, Zn, Cd and Cr showed similar trends of spatial variation and the correlations between the concentrations of every two heavy metals were significantly positive except for the correlation between Pb and Cr concentrations. By using Nemerow index method, Enrichment factor and Sediment Quality Guidelines, it is found that Hangzhou Bay and Jiulong River Estuary were polluted, Yingluo Bay and Dongzhaigang Bay were Cd-rich areas. Except Beidaihe shoal, Sishili Bay and Yingluo Bay that were not exposed to any ecological risk of heavy metals and had no adverse biotoxic effects, the other 11 typical intertidal zone areas were exposed to moderate ecological risk of heavy metals in the sediment with potential adverse biotoxic effects.
Show more [+] Less [-]Fishing marine debris in a northeast Brazilian beach: Composition, abundance and tidal changes
2019
Ramos, Jonas A.A. | Pessoa, Willy V.N.
This study aims to examine the composition and the spatial/tidal changes of marine debris caught with a fishing net during a fishery survey in two different areas of a sand beach at the northeast of Brazil. Samples were conducted weekly, at each moon phase, for two months using a beach seine net in the surf zone. Abundance of debris were estimate by swept area (items·km⁻¹ and g·km⁻¹). A total of 12 categories of debris were recorded. Plastic – both hard and soft types - was the most abundant debris category. Most fragments were classified as macro (20–100 mm) and mega debris (>100 mm). Significant differences (P < 0.05) between areas and tides were registered for plastic, metal and cloth. Spring tides were responsible for the high rates of marine debris found in the surf zone of Miramar beach. The results demonstrate the occurrence and abundance of litter in this fish nursery area and reinforce the need and importance of environmental protection and educational programs.Marine debris caught by a fishing net in the surf zone of Brazilian beach.
Show more [+] Less [-]PAHs and PCBs residues and consumption risk assessment in farmed yellow croaker (Larimichthys crocea) from the East China Sea, China
2019
Wang, Xiaoyan | Celander, Malin C. | Yin, Xiaolong | Zhang, Zhichao | Chen, Yongjiu | Xu, Huanzhi | Yu, Xinwei | Xu, Kaida | Zhang, Xiumei | Kanchanopas-Barnette, Praparsiri
Large yellow croaker (Larimichthys crocea) purchased from five different farming sites in Zhoushan Archipelago and Xiangshan Harbor in the East China Sea, China were analyzed for polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Concentrations of PAHs and PCBs in the edible muscle of L. crocea ranged from 83.14 to 174.68 ng/g wet weight (or 266.89 to 695.24 ng/g dry weight) and 3.89 to 17.40 ng/g wet weight (or 15.50 to 54.25 ng/g dry weight), respectively. Incremental lifetime cancer risk (ILCR) associated with the dietary intake of PAHs and PCBs in L. crocea was assessed. Results showed that levels of PAHs in L. crocea were high enough to cause potential carcinogenic risks for human consumption, while, levels of PCBs in fish samples were of low significant carcinogenic risk.
Show more [+] Less [-]Microtopographical modification by a herbivore facilitates the growth of a coastal saltmarsh plant
2019
Qiu, Dongdong | Yan, Jiaguo | Ma, Xu | Luo, Meng | Wang, Qing | Cui, Baoshan
Increasing evidence shows that herbivores can facilitate plant growth and maintain the resistance of plant communities to trophic consumption in a variety of ecosystems. However, the positive effects of herbivores on annual saltmarsh plants in coastal ecosystems are relatively understudied. In this study, field investigations and manipulative experiments were conducted to explore whether and how microtopographical modification by the herbivorous crab Helice tientsinensis stimulates the growth of the saltmarsh plant Suaeda salsa. Results showed that, despite grazing on S. salsa, H. tientsinensis can promote density, total biomass, average plant height, average root length, and average biomass through burrowing-generated concave-convex microtopography, which can improve the edaphic environment (decreased soil hardness and salinity, and increased soil moisture content, oxidation-reduction potential, and carbon and nitrogen content), and provide plants more clustered growth opportunities that could facilitate positive intraspecific plant interactions. This study can provide scientific guidance for ecosystem restoration in coastal intertidal saltmarshes.
Show more [+] Less [-]Can plastics affect near surface layer ocean processes and climate?
2019
VishnuRadhan, Renjith | Eldho, T.I. | David, T Divya
Plastics in the ocean are of great concern nowadays, and are often referred to as the apocalyptic twin of climate change in terms of public fear and the problems they pose to the aquatic and terrestrial environment. The number of studies focusing on the ecological effects and toxicity of plastics has substantially increased in the last few years. Considering the current trends in the anthropogenic activities, the amount of plastics entering the world oceans is increasing exponentially, but the oceans have a low assimilative capacity for plastics and the near-surface layer of it is a finite space. If loading of the oceans with plastics continues at the current rate, the thin sea surface microlayer can have a substantial amount of plastics comparable to the distribution of phytoplankton, at least in the major oceanic gyres and coastal waters in the future. Also, processes like biofouling can cluster microplastics in dense fields in the near-surface layer. Plastics can contribute to the warming or cooling of the water column by scattering and attenuating incoming solar radiation, leading to a potential change in the optical and other physico-chemical properties of the water column. We propose a new notion that changes in solar radiation in the water column due to the plastics have the potential to affect the physical processes in the ocean surface and near-surface layers, and can induce climate feedback cycles. The future can be very different, if plastics evolve as one of the key players affecting the ocean physical processes and hence this is the time to tackle this puzzle with appropriate strategies or let the genie out of the bottle.
Show more [+] Less [-]Occurrence of antibiotics and antibiotic resistance genes in a typical estuary aquaculture region of Hangzhou Bay, China
2019
Yuan, Julin | Ni, Meng | Liu, Mei | Zheng, Yao | Gu, Zhimin
The widespread use of antibiotics in aquaculture can potentially lead to the emergence of antibiotic resistance genes (ARGs) and threaten human health by entering the food chain. To assess the environmental risk posed by antibiotics in China, the spatial-temporal distribution and correlation of 8 antibiotics based on the abundance of 11 ARGs in water sources, pond water, and sediment in 8 ponds were determined. The results indicated that sul1 was the predominant ARG in water sources and pond water, and tetC was the most in the sediment. A trend of increasing abundance of ARGs was observed with increased rearing density and pond age. Compared to monoculture, shrimp culture integrated with different trophic levels of fish farming could influence the abundance of ARGs. There was also a significant correlation between the abundance of ARGs and antibiotic concentration in the sediment, while no correlation was observed in water sources and pond water.
Show more [+] Less [-]Oceanographic characteristics of the Adriatic Sea – Support to secondary HAOP spread through natural dispersal
2019
Kraus, Romina | Grilli, Federica | Supić, Nastjenjka | Janeković, Ivica | Brailo, Marina | Cara, Magdalena | Cetinić, Ana Bratoš | Campanelli, Alessandra | Cozzi, Stefano | D'Adamo, Raffaele | Djakovac, Tamara | Dutour Sikirić, Mathieu | Flander-Putrle, Vesna | Francé, Janja | Joksimović, Danijela | Klun, Katja | Kolitari, Jerina | Kralj, Martina | Kušpilić, Grozdan | Marini, Mauro | Matić, Frano | Mikuš, Josip | Ninčević-Gladan, Živana | Pansera, Marco | Pećarević, Marijana | Precali, Robert | Prusina, Ivana | Relitti, Federica | Santucci, Angela | Specchiulli, Antonietta | Škalic, Denis
Vessels, specifically ballast water and hull fouling, are a major vector for the introduction of non-indigenous species (NIS) in European seas. The Mediterranean is one of the world's marine regions where their invasion is heaviest. The shallow Adriatic basin is a highly sensitive area that is already experiencing its consequences. The secondary spread of NIS over a wider area through natural dispersion is a complex process that depends on a wide range of oceanographic factors. This work analysed the dataset of the BALMAS project, in whose framework twelve ports in the Adriatic Sea were subjected to a Port Baseline Survey (PBS), to estimate the natural spread of NIS organisms from their port of arrival to the wider Adriatic basin. Its findings indicate that the prevailing water circulation patterns facilitate the natural dispersal of harmful aquatic organisms and pathogens (HAOP).
Show more [+] Less [-]Fungal communities in oil contaminated mangrove sediments – Who is in the mud?
2019
Ghizelini, Angela Michelato | Martins, Kelly Geronazzo | Gießelmann, Urs Christian | Santoro, Erika | Pasqualette, Laura | Mendonça-Hagler, Leda C.S. | Rosado, Alexandre Soares | MacRae, Andrew
Mangroves are ecosystems located in tropical and subtropical regions of the world and are vital for coastal protection. Their unique characteristics make them hotspots for carbon cycling and biological diversity. Studies on isolated filamentous fungi and environmental and anthropogenic factors that influence sediments offer new understandings on how to preserve mangroves. Here we report on the filamentous fungi isolated from four mangroves. We correlated fungal community composition with sediment texture, polycyclic aromatic hydrocarbons concentration (oil pollution), pH, salinity, organic matter, total and thermotolerant coliforms (sewage pollution). In total we identified 34 genera and 97 species. The most polluted sites had highest species richness whereas the best preserved site showed the lowest species richness. Oil spill and sewage pollution were identified as the drivers of fungal community composition in the most polluted sites. We found very distinct fungal communities with no >5 species shared between any two mangrove sites.
Show more [+] Less [-]Accumulation and potential sources of lead in marine organisms from coastal ecosystems of the Chilean Patagonia and Antarctic Peninsula area
2019
Espejo, Winfred | Padilha, Janeide de A. | Gonçalves, Rodrigo A. | Dorneles, Paulo R. | Barra, Ricardo | Oliveira, Douglas | Malm, Olaf | Chiang, Gustavo | Celis, José E.
Environmental concentrations of Pb have been increased due to anthropogenic activities, which have provoked the released of this element to the environment in large amounts. To understand how Pb behaves in remote southern marine ecosystems, we measured Pb concentrations and isotope ratios in biota from coastal marine ecosystems of the Chilean Patagonia and the Antarctic Peninsula area. Lead concentrations in the aquatic organisms ranged from 0.02 to 1.19 mg kg−1 d.w. In Patagonia, higher Pb levels were found in fish than in invertebrates (crab, shrimp, porifera, limpet and shellfish). In comparison with the baseline reference values from other parts of the world, fishes exhibited lower Pb levels. The results of Pb isotopic compositions indicated that the bioaccumulation of Pb in marine organisms come from different anthropogenic sources. These Pb levels might be useful for further studies that allow a deeper evaluation of sources for Pb contamination in these remote ecosystems.
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