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Occurrence and spatial distribution of antibiotic resistance genes in the Bohai Sea and Yellow Sea areas, China
2019
Lu, Jian | Zhang, Yuxuan | Wu, Jun | Wang, Jianhua | Zhang, Cui | Lin, Yichen
Rapid development of Bohai and Yellow Sea Economic Rim has led to the concern of emerging contamination of marine environments. This study investigated the spatial distribution of antibiotic resistance genes (ARGs) in Bohai and Yellow Sea areas. A large scale sampling from Bohai Sea, Yellow Sea and the major cities along the coastline from the mouth of Yalu River to the Yangtze River was performed. The spatial distribution of target ARGs based on the absolute abundances was in the trend of river water ≈ coastal water > the Bohai Sea > the Yellow Sea, inshore > offshore and inner bay > bay mouth. The total absolute abundances of selected ARGs in the coastal waters (1.23 × 10⁴–3.94 × 10⁵ copies/mL) were about 1–4 orders of magnitude higher than those in the sea (21.1–8.00 × 10³ copies/mL). The abundances of ARGs fluctuated greatly in the Yellow Sea and the coastal areas. Sulfonamide resistance genes hold the highest abundances in the Bohai and Yellow Sea (up to 2.13 × 10³ copies/mL of sul1 and 6.23 × 10³ copies/mL of sul2), followed by tetracycline and quinolone resistance genes, while qnrA hold the highest abundances in coastal areas (up to 3.66 × 10⁵ copies/mL). The distribution coefficients of target genes between sediments and corresponding water samples were more than 1.0 in the majority of different aquatic systems. According to the principle component analysis and redundancy analysis, water samples collected from the sea clustered together while those from the coastal zone and rivers were separated. Ammonium and nitrate played important roles in the distribution and variation of ARGs. Co-occurrence network analysis revealed that the potential multi-antibiotics resistant bacteria were detected with higher abundances in the Yellow Sea than in the Bohai Sea. These observations provided a comprehensive new insight into the pollution status of ARGs in the Bohai and Yellow Sea areas.
Show more [+] Less [-]Chronic exposure to copper and zinc induces DNA damage in the polychaete Alitta virens and the implications for future toxicity of coastal sites
2018
Watson, Gordon J. | Pini, Jennifer M. | Richir, Jonathan
Copper and zinc are metals that have been traditionally thought of as past contamination legacies. However, their industrial use is still extensive and current applications (e.g. nanoparticles and antifouling paints) have become additional marine environment delivery routes. Determining a pollutant's genotoxicity is an ecotoxicological priority, but in marine benthic systems putative substances responsible for sediment genotoxicity have rarely been identified. Studies that use sediment as the delivery matrix combined with exposures over life-history relevant timescales are also missing for metals. Here we assess copper and zinc's genotoxicity by exposing the ecologically important polychaete Alitta virens to sediment spiked with environmentally relevant concentrations for 9 months. Target bioavailable sediment and subsequent porewater concentrations reflect the global contamination range for coasts, whilst tissue concentrations, although elevated, were comparable with other polychaetes. Survival generally reduced as concentrations increased, but monthly analyses show that growth was not significantly different between treatments. The differential treatment mortality may have enabled the surviving worms in the high concentration treatments to capture more food thus removing any concentration treatment effects for biomass. Using the alkaline comet assay we confirm that both metals via the sediment are genotoxic at concentrations routinely found in coastal regions and this is supported by elevated DNA damage in worms from field sites. However, combined with the growth data it also highlights the tolerance of A. virens to DNA damage. Finally, using long term (decadal) monitoring data we show stable or increasing sediment concentrations of these metals for many areas. This will potentially mean coastal sediment is a significant mutagenic hazard to the benthic community for decades to come. An urgent reappraisal of the current input sources for these ‘old pollutants’ is, therefore, required.
Show more [+] Less [-]Effects of a glyphosate-based herbicide on Fucus virsoides (Fucales, Ochrophyta) photosynthetic efficiency
2018
Falace, Annalisa | Tamburello, Laura | Guarnieri, G. (Giuseppe) | Kaleb, Sara | Papa, Loredana | Fraschetti, Simonetta
Herbicides are increasingly recognised as sources of water pollution. Glyphosate-based herbicides (GBHs) are widely used because of their low cost and high effectiveness. By measuring the photosynthetic efficiency of Fucus virsoides fronds exposed to a GBH (Roundup® Power 2.0), we investigated the effect of a continuous exposure (6 days) and the potential of recovery after a short exposure (24 h). Both experiments were carried out combining GBH with and without nutrient enrichment, simulating a runoff event. A factorial experimental design allowed us to assess the potential of interactions between GBH and nutrients, which are likely to co-occur in coastal areas. Our results show deleterious effects of GBH at low concentration on F. virsoides, independently from the duration of exposure and the presence of nutrients.
Show more [+] Less [-]Baseline characterisation of source contributions to daily-integrated PM2.5 observations at Cape Grim using Radon-222
2018
Crawford, Jagoda | Chambers, Scott D. | Cohen, David D. | Williams, Alastair G. | Atanacio, Armand
We discuss 15 years (2000–2015) of daily-integrated PM₂.₅ samples from the Cape Grim Station. Ion beam analysis and positive matrix factorisation are used to identify six source-type fingerprints: fresh sea salt (57%); secondary sulfate (14%); smoke (13%); aged sea salt (12%); soil dust (2.4%); and industrial metals (1.5%). An existing hourly radon-only baseline selection technique is modified for use with the daily-integrated observations. Results were not significantly different for days on which >20 hours were below the baseline radon threshold compared with days when all 24 hours satisfied the baseline criteria. This relaxed daily baseline criteria increased the number of samples for analysis by almost a factor of two. Two radon baseline thresholds were tested: historic (100 mBq m⁻³), and revised (50 mBq m⁻³). Median aerosol concentrations were similar for both radon thresholds, but maximum values were higher for the 100 mBq m⁻³ threshold. Back trajectories indicated more interaction with southern Australia and the Antarctic coastline for air masses selected with the 100 mBq m⁻³ threshold. Radon-only baseline selection using the 50 mBq m⁻³ threshold was more selective of minimal terrestrial influence than a similar recent study using wind direction and back trajectories. The ratio of concentrations between terrestrial and baseline days for the primary sources soil, smoke and industrial metals was 3.4, 2.6, and 5.5, respectively. Seasonal cycles of soil dust had a summer maximum and winter minimum. Seasonal cycles of smoke were of similar amplitude for terrestrial and baseline events, but of completely different shape: peaking in autumn and spring for terrestrial events, compared to summer for baseline conditions. Seasonal cycles of industrial metals had a summer maximum and winter minimum. A significant fraction of the Cape Grim baseline smoke and industrial metal contributions appeared to be derived from long-term transport (>3 weeks since last terrestrial influence).
Show more [+] Less [-]Risk assessment of microplastics in the ocean: Modelling approach and first conclusions
2018
Everaert, Gert | Van Cauwenberghe, Lisbeth | De Rijcke, Maarten | Koelmans, Albert A. | Mees, Jan | Vandegehuchte, Michiel | Janssen, Colin R.
We performed an environmental risk assessment for microplastics (<5 mm) in the marine environment by estimating the order of magnitude of the past, present and future concentrations based on global plastic production data. In 2100, from 9.6 to 48.8 particles m⁻³ are predicted to float around in the ocean, which is a 50-fold increase compared to the present-day concentrations. From a meta-analysis with effect data available in literature, we derived a safe concentration of 6650 buoyant particles m⁻³ below which adverse effects are not likely to occur. Our risk assessment (excluding the potential role of microplastics as chemical vectors) suggests that on average, no direct effects of free-floating microplastics in the marine environment are to be expected up to the year 2100. Yet, even today, the safe concentration can be exceeded in sites that are heavily polluted with buoyant microplastics. In the marine benthic compartment between 32 and 144 particles kg⁻¹ dry sediment are predicted to be present in the beach deposition zone. Despite the scarcity of effect data, we expect adverse ecological effects along the coast as of the second half of the 21st century. From then ambient concentrations will start to outrange the safe concentration of sedimented microplastics (i.e. 540 particles kg⁻¹ sediment). Additional ecotoxicological research in which marine species are chronically exposed to realistic environmental microplastic concentration series are urgently needed to verify our findings.
Show more [+] Less [-]Environmental risk assessment of triclosan and ibuprofen in marine sediments using individual and sub-individual endpoints
2018
Pusceddu, F.H. | Choueri, R.B. | Pereira, C.D.S. | Cortez, F.S. | Santos, D.R.A. | Moreno, B.B. | Santos, A.R. | Rogero, J.R. | César, A.
The guidelines for the Environmental Risk Assessment (ERA) of pharmaceuticals and personal care products (PPCP) recommend the use of standard ecotoxicity assays and the assessment of endpoints at the individual level to evaluate potential effects of PPCP on biota. However, effects at the sub-individual level can also affect the ecological fitness of marine organisms chronically exposed to PPCP. The aim of the current study was to evaluate the environmental risk of two PPCP in marine sediments: triclosan (TCS) and ibuprofen (IBU), using sub-individual and developmental endpoints. The environmental levels of TCS and IBU were quantified in marine sediments from the vicinities of the Santos submarine sewage outfall (Santos Bay, São Paulo, Brazil) at 15.14 and 49.0 ng g⁻¹, respectively. A battery (n = 3) of chronic bioassays (embryo-larval development) with a sea urchin (Lytechinus variegatus) and a bivalve (Perna perna) were performed using two exposure conditions: sediment-water interface and elutriates. Moreover, physiological stress through the Neutral Red Retention Time Assay (NRRT) was assessed in the estuarine bivalve Mytella charruana exposed to TCS and IBU spiked sediments. These compounds affected the development of L. variegatus and P. perna (75 ng g⁻¹ for TCS and 15 ng g⁻¹ for IBU), and caused a significant decrease in M. charruana lysosomal membrane stability at environmentally relevant concentrations (0.08 ng g⁻¹ for TCS and 0.15 ng g⁻¹ for IBU). Chemical and ecotoxicological data were integrated and the risk quotient estimated for TCS and IBU were higher than 1.0, indicating a high environmental risk of these compounds in sediments. These are the first data of sediment risk assessment of pharmaceuticals and personal care products of Latin America. In addition, the results suggest that the ERA based only on individual-level and standard toxicity tests may overlook other biological effects that can affect the health of marine organisms exposed to PPCP.
Show more [+] Less [-]Major threats of pollution and climate change to global coastal ecosystems and enhanced management for sustainability
2018
Lü, Yonglong | Yuan, Jingjing | Lu, Xiaotian | Su, Chao | Zhang, Yueqing | Wang, Chenchen | Cao, Xianghui | Li, Qifeng | Su, Jilan | Ittekkot, Venugopalan | Garbutt, Richard Angus | Bush, Simon | Fletcher, Stephen | Wagey, Tonny | Kachur, Anatolii | Sweijd, Neville
Coastal zone is of great importance in the provision of various valuable ecosystem services. However, it is also sensitive and vulnerable to environmental changes due to high human populations and interactions between the land and ocean. Major threats of pollution from over enrichment of nutrients, increasing metals and persistent organic pollutants (POPs), and climate change have led to severe ecological degradation in the coastal zone, while few studies have focused on the combined impacts of pollution and climate change on the coastal ecosystems at the global level. A global overview of nutrients, metals, POPs, and major environmental changes due to climate change and their impacts on coastal ecosystems was carried out in this study. Coasts of the Eastern Atlantic and Western Pacific were hotspots of concentrations of several pollutants, and mostly affected by warming climate. These hotspots shared the same features of large populations, heavy industry and (semi-) closed sea. Estimation of coastal ocean capital, integrated management of land-ocean interaction in the coastal zone, enhancement of integrated global observation system, and coastal ecosystem-based management can play effective roles in promoting sustainable management of coastal marine ecosystems. Enhanced management from the perspective of mitigating pollution and climate change was proposed.
Show more [+] Less [-]Relationships between plastic litter and chemical pollutants on benthic biodiversity
2018
D’Alessandro, Michela | Esposito, Valentina | Porporato, Erika M.D. | Berto, Daniela | Renzi, Monia | Giacobbe, Salvatore | Scotti, Gianfranco | Consoli, Pierpaolo | Valastro, Gaetano | Andaloro, Franco | Romeo, Teresa
Five Descriptors (D) of Marine Strategy Framework Directive (MSFD): marine litter (D10), non-indigenous species (D2) and organic and inorganic pollutants (D8), were estimated in a coastal area of GSA 16 (Augusta harbour, Central Mediterranean Sea) in order to study their effects on the biodiversity (D1) of the benthic community D6) and to improve data for the MSFD. Investigation of plastic debris had led to the identification of 38 fragments divided into four categories, among which microplastics resulted as the most abundant. Six non-indigenous species, belonging to Polychaeta (Kirkegaardia dorsobranchialis, Notomastus aberans, Pista unibranchia, Pseudonereis anomala, Branchiomma bairdi) and Mollusca (Brachidontes pharaonis) were found. Biodiversity and benthic indices suggested a generalised, slightly disturbed ecological status. Anthracene, Zinc and Chrome were the most abundant chemical compounds in analysed sediments. Significant correlations were found between the abundance of trace elements vs biotic indices and between plastic debris vs biodiversity and benthic indices. This study represents the first report about the abundance of plastic debris and its relationship to contaminants and infauna in Augusta harbour. Our results can provide useful information for national and international laws and directives.
Show more [+] Less [-]Abundance, composition, and distribution of microplastics larger than 20 μm in sand beaches of South Korea
2018
Eo, Soeun | Hong, Sang Hee | Song, Young Kyoung | Lee, Jongsu | Lee, Jongmyoung | Shim, Won Joon
To support microplastic management, the abundance, composition, and spatial distribution of microplastics on a national scale must be known. Hence, we studied the baseline level of microplastic pollution at 20 sandy beaches along the South Korean coast. All microplastic particles extracted from the sand samples were identified down to 20 μm in size using Fourier transform infrared spectroscopy. The abundances of large microplastics (L-MPs; 1–5 mm) and small microplastics (S-MPs; 0.02–1 mm) were in the range of 0–2088 n/m2 and 1400–62800 n/m2, respectively. Maximum microplastic abundance was in the size range of 100–150 μm, and particles smaller than 300 μm accounted for 81% of the total abundance. Expanded polystyrene (EPS) accounted for 95% of L-MPs, whereas S-MPs were predominantly composed of polyethylene (49%) and polypropylene (38%). The spatial distribution of L-MPs, excluding EPS, was significantly related to population, precipitation, proximity to a river mouth and abundance of macroplastic debris on beach. However, there were no relationships between S-MPs and other environmental and source-related factors, except for macroplastic debris and L-MPs excluding EPS. These results imply that S-MPs are mainly produced on beaches by weathering, whereas L-MPs other than EPS are mainly introduced from land-based sources and are also partly produced on beaches.
Show more [+] Less [-]Dynamic multimedia fate simulation of Perfluorooctane Sulfonate (PFOS) from 1981 to 2050 in the urbanizing Bohai Rim of China
2018
Su, Chao | Lü, Yonglong | Wang, Tieyu | Lu, Xiaotian | Song, Shuai | Li, Lei | Kifāyatullāh, K̲h̲ān | Wang, Chenchen | Liang, Ruoyu
Perfluorooctane sulfonate (PFOS) and related substances are widely used in various industrial and commercial applications in China that ultimately discharge sufficient quantities of PFOS to the environment. It remains unclear how emissions of PFOS ultimately affect its concentrations as well as its fate in the environment. In this study, an improved Berkeley-Trent (BETR) multimedia model is developed to predict the PFOS levels with spatial and temporal distributions on unsteady state mode from 1981 to 2050, by taking the Bohai Rim of China as a case. The results showed that the modeled concentrations agreed well with the measured data. According to the model, PFOS concentrations in fresh water peaked in some months after the peak emission (2008 or 2009), whereas in urban soil the concentrations increased to peak slightly later (around 2014). Among the selected regions, Beijing and Tianjin were simulated with higher PFOS levels in the past and present because of their higher urbanization and industrialization since the 1980s, while in the future, Shandong and Liaoning are expected to have higher concentrations of PFOS than those in Beijing. The water system including coastal water, fresh water and sediment was the biggest sink for PFOS for coastal regions. Among the chemical inputs, direct primary emissions played a more important role, whereas for chemical removal processes, inter-regional advection and background outflow were the predominant pathways. The results would be useful to control the PFOS releases in China and will help the management agencies to implement the “Stockholm Convention” effectively.
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