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Approaches to reduce noise from ships operating in important killer whale habitats 全文
2019
Williams, Rob | Veirs, Scott | Veirs, Val | Ashe, Erin | Mastick, Natalie
Shipping is key to global trade, but is also a dominant source of anthropogenic noise in the ocean. Chronic noise from ships can affect acoustic quality of important whale habitats. Noise from ships has been identified as one of three main stressors–in addition to contaminants, and lack of Chinook salmon prey–in the recovery of the endangered southern resident killer whale (SRKW) population. Managers recognize existing noise levels as a threat to the acoustical integrity of SRKW critical habitat. There is an urgent need to identify practical ways to reduce ocean noise given projected increases in shipping in the SRKW's summertime critical habitat in the Salish Sea. We reviewed the literature to provide a qualitative description of mitigation approaches. We use an existing ship source level dataset to quantify how some mitigation approaches could readily reduce noise levels by 3–10 dB.
显示更多 [+] 显示较少 [-]Alterations of the human skin microbiome after ocean water exposure 全文
2019
Nielsen, Marisa Chattman | Jiang, Sunny C.
Skin is the body's first line of defense against invading microorganisms. The skin microbiome has been shown to provide immunity against exogenous bacterial colonization. Recreational water exposures may alter the skin microbiome and potentially induce skin infections. This study explored the link between ocean water exposures and the human skin microbiome. Skin microbiome samples were collected, using swabs, from human participants' calves before and after they swam in the ocean, and at 6 hour and 24 hour post-swim. Genomic analysis showed that skin microbiomes were different among individuals before swimming. But after swimming, microbial communities were no longer different, which was demonstrated by a decrease in inter-sample diversity. Taxonomic analysis showed that ocean bacteria, including potential pathogens, replaced the native skin bacteria and remained on the skin for at least 24 hour post-swim. This research provides insight into the relationship between the human skin microbiome and the environment.
显示更多 [+] 显示较少 [-]Metalliferous Mine Dust: Human Health Impacts and the Potential Determinants of Disease in Mining Communities 全文
2019
Entwistle, Jane A. | Hursthouse, Andrew S. | Marinho Reis, Paula A. | Stewart, Alex G.
PURPOSE OF REVIEW: Many factors influence the health impact of exposure to metalliferous mine dusts and whilst the underpinning toxicology is pivotal, it is not the only driver of health outcomes following exposure. The purpose of this review is twofold: (i) to highlight recent advances in our understanding of the hazard posed by metalliferous mine dust and (ii) to broaden an often narrowly framed health risk perspective to consider the wider aetiology of the potential determinants of disease. RECENT FINDINGS: The hazard posed by metalliferous dusts depends not only on their abundance and particle size but other properties such as chemical composition, solubility, shape, and surface area, which all play a role in the associated health effects. A better understanding of the mechanisms that lead to toxicity, such as recent advances in our understanding of the role played by reactive oxygen species (ROS), can help in the development of improved in vitro models to support risk assessments, whilst biomonitoring studies have the potential to guide risk management decisions for mining communities. Environmental exposures are complex; complex geochemically and complex geographically. Research linking the environment to human health is starting to mature, highlighting the subtlety of multiple exposures, mixtures of substances, and the cumulative legacy effects of life in disrupted and stressed environments. We are evolving more refined biomarkers to identify these responses, which enhances our appreciation of the burden of effects on society and also directs us to more sophisticated risk assessment approaches to adequately address evolving regulatory and societal needs.
显示更多 [+] 显示较少 [-]Assessment of input of organic micropollutants and microplastics into the Baltic Sea by urban waters 全文
2019
Bollmann, Ulla E. | Simon, Marta | Vollertsen, Jes | Bester, Kai
We assess how different micropollutants and microplastics, connected to wastewater are introduced into the Baltic Sea. The relevance of untreated wastewater, treated wastewater, treated and untreated rain runoff, as well as combined sewer overflow (CSO), is assessed in respect to mass balance, as well as relative inflows of micropollutants and -plastics into the Baltic Sea. To achieve this, modelling based on data on exemplary sewer systems and measured micropollutant concentrations in the single sources were used. Most compounds reach the receiving Baltic Sea via treated wastewater. A few exceptions are compounds that are removed to a very high extent in wastewater treatment plants. For these compounds, the emissions with stormwater (e.g., terbutryn) or untreated wastewater (e.g., triclosan) are dominating. Additionally, compounds that are discharged with the water that is running off urban surfaces are introduced into marine areas via rain runoff. These data are used to forecast a total mass load and concentrations that can be expected in the Baltic Sea. Massloads are expected to be between 0.1 and 5.9 t/a for triclosan and TCPP (tris (2-chloropropyl) phosphate) and 0.2 t/a for microplastic particles. The expected concentrations in open Baltic Sea waters range from 0.01 to 26 ng/L.
显示更多 [+] 显示较少 [-]Marine litter in the Croatian part of the middle Adriatic Sea: Simultaneous assessment of floating and seabed macro and micro litter abundance and composition 全文
2019
Palatinus, Andreja | Kovač Viršek, Manca | Robič, Uroš | Grego, Mateja | Bajt, Oliver | Šiljić, Jasna | Suaria, Giuseppe | Liubartseva, Svitlana | Coppini, Giovanni | Peterlin, Monika
In this study, abundance, distribution and composition of floating and seabed macro and micro litter in the Central Adriatic Sea were assessed. Floating macro litter observations were made. Floating and seabed micro litter were sampled with manta net and Van Veen grab, respectively. Micro litter particles visually found under the microscope were chemically analyzed with Fourier Transform Infrared microscope. Average calculated concentrations of floating macro (175 items/km2), floating micro (127 thousand particles/km2) and seabed micro litter (36 particles/100 g dry weight) show similar values as other published studies from the Mediterranean Sea. A statistically significant (p < 0.01) correlation between the floating micro and macro litter concentrations was found for the sites located in the channel waters. Disagreement between model and observations revealed gaps in our knowledge concerning the sea circulation and litter sources. Simultaneous samplings and observations of marine litter in different marine compartments proved possible, efficient and informative.
显示更多 [+] 显示较少 [-]Quantitative evaluation of n-alkanes, PAHs, and petroleum biomarker accumulation in beach-stranded tar balls and coastal surface sediments in the Bushehr Province, Persian Gulf (Iran) 全文
2019
Dashtbozorg, Mehdi | Riyahi Bakhtiari, Alireza | Shushizadeh, Mohammad Reza | Taghavi, Lobat
Coastal areas within the Bushehr Province (BP), Persian Gulf, Iran, face great challenges due to the heavy organic contamination caused by rapid industrialization, and the presence of numerous oil fields. In addition, in 2014, a significant number of tar balls are found along the coasts of BP. A total of 96 samples (48 coastal sediments and 48 tar balls) were taken from eight sampling points at the BP coast during the summer of 2014. These samples were analyzed to identify the sources and characteristics of their organic matter using diagnostic ratios and fingerprint analysis based on the distribution of the source-specific biomarkers of n-alkanes, PAHs,¹1Polycyclic Aromatic Hydrocarbons hopanes and steranes. Mean concentration of n-alkanes (μg g⁻¹ dw) and PAHs (ng g⁻¹ dw) varied respectively from 405 to 220,626, and 267 to 23,568 in coastal sediments, while ranged respectively from 664 to 145,285 and 390 to 46,426 in tar balls. In addition, mean concentration of hopanes and steranes (ng g⁻¹ dw) were between 18.17 and 3349 and 184.66 to 1578 in coastal sediments, whereas in tar balls were 235–1899 and 520–1504, respectively. Pri/Phy²2Pristane/Phytane ratio was 0.25 to 1.51 (0.65) and 0.36 to 1 (0.63) in coastal sediment and tar ball samples, respectively, and the occurrence of UCM³3Unresolved Complex Mixture in both matrices, reflecting the petrogenic OM⁴4Organic Matter inputs and chronic oil contamination, respectively. The C₃₀ and C₂₉ homologues followed Gammacerane were detected in both matrices, in particular those collected from intensive industrial activities, suggesting petrogenic sources of OM. The coastal sediment PAHs profiles were significantly dominated by HMW⁵5Higher Molecular Weight-PAHs in the Bahregan Beach (BAB) (78% of total PAHs), Bandare-Genaveh (GP) (66%), and Bandare-Bushehr (BUB) (61%) stations, while the Bashi Beach (BSB) (40%), Bandare-Kangan (KP) (57%), and Bandare-Asaluyeh (AP) (51%) stations exhibited higher proportion of LMW⁶6Lower Molecular Weight-PAHs. PCA⁷7Principal Component Analysis indicated that the tar ball and coastal sediment samples deposited along the Southwest of the BP beaches are most likely originated from the Abuzar oil. Based on the intensity of the anthropogenic activities, NPMDS⁸8Non-Parametric Multi-Dimensional Scaling analysis revealed that the GP, BAB, NNP, AP, and KP sampling sites had a high concentration of detected organic pollutants. To the best of our knowledge, this is the first study that investigates oil pollution in costal sediments and tar balls in the BP, providing insights in to the fate of oil in the coastal areas of the Persian Gulf, Iran.
显示更多 [+] 显示较少 [-]Composition variations and spatiotemporal dynamics of dissolved organic matters during the occurrence of green tide (Ulva prolifera blooms) in the Southern Yellow Sea, China 全文
2019
Li, Xiuzhu | Li, Conghe | Bai, Ying | Shi, Xiaoyong | Su, Rongguo
Seawater samples were collected from April 6 to September 6, 2017 in the Southern Yellow Sea, China where green tides often occurred, and analyzed for nutrients, dissolved organic carbon (DOC), and fluorescent dissolved organic matter (FDOM). The DOC concentrations increased significantly in the green tide areas by approximately 1.2 times compared to those in the non-green tide areas. From the large-scale outbreak to the complete dissipation of the green tide, the fluorescence intensities of the four FDOM fluorescent components identified in the green tide areas were significantly higher than those in the non-green tide areas. During the extinction period, the fluorescence intensities of the three humus-like components and one protein-like component were approximately 1.8 and 1.3 times higher than those in the non-green tide areas, respectively. These findings suggested that the outbreak of green tide could release DOM into water and affect the biogeochemical cycle in green tide regions.
显示更多 [+] 显示较少 [-]Persistent organic pollutants in killer whales (Orcinus orca) of the Russian Far East 全文
2019
Atkinson, Shannon | Branson, Maile | Burdin, A. (Aleksandr) | Boyd, Daryle | Ylitalo, Gina M.
Exposure to persistent organic pollutants (POPs) is a key factor in predicting the collapse of global killer whale (Orcinus orca) populations due to reproductive and immune impacts. Blubber biopsies from killer whales (n = 25) were collected in the Russian Far East in 2002–2004. Biopsies were analyzed for ΣDDT, ΣPCB, and HCB concentrations. A subset of biopsies was further examined for additional contaminants, ΣPBDE, ΣHCH, ΣCHLD, mirex, and dieldrin. Mean concentrations were compared across resident (fish-eating) and transient (mammal-eating) ecotypes and between sexes. ΣPCB analytes (resident males 18,000, resident females 1200, and transient males 420,000 ng g⁻¹ lw) and HCB (resident males 750, resident females 81, and transient males 6200 ng g⁻¹ lw) differed significantly (p < 0.001). No significant difference was observed between sexes. Notable disparities in contaminant levels between ecotypes support the major toxicological theories of contaminant bioaccumulation and dietary impacts on individual contaminant load.
显示更多 [+] 显示较少 [-]Occurrence of tire wear particles and other microplastics within the tributaries of the Charleston Harbor Estuary, South Carolina, USA 全文
2019
Leads, Rachel R. | Weinstein, John E.
Microplastics (<5 mm) are ubiquitous in the marine environment, occurring in both sediments and surface waters worldwide. However, few studies have documented the presence of microplastics and tire wear particles in coastal rivers. A survey of microplastics and low-density tire wear particles (≥63 μm) in the sediment and surface water of the three major tributaries within the Charleston Harbor estuary was conducted. Intertidal sediment, subtidal sediment, and sea surface microlayer concentrations ranged from 0 to 652 microplastics/m², 3–4,375 microplastics/kg wet weight, and 3–36 microplastics/L, respectively. Blue fibers and tire wear particles were the two most abundant microplastic types observed, constituting 26.2% and 17.1%, respectively, of total microplastics. Tire wear particles were primarily identified by morphology, and ATR-FTIR analysis was conducted for a small subset (n = 5) of larger particles (≥500 μm). The present study provides the first microplastic field assessment of low-density tire wear particles in estuarine tributaries.
显示更多 [+] 显示较少 [-]High mercury concentrations in Atlantic Goliath Grouper: Spatial analysis of a vulnerable species 全文
2019
Malinowski, C.R.
The Atlantic Goliath Grouper Epinephelus itajara is currently a protected species in the southeastern United States waters of the Atlantic and the Gulf of Mexico and is considered vulnerable throughout its geographic range. In this study, I evaluated mercury concentrations in their tissues (muscle, liver), which revealed high concentrations (μg/g ww) of mercury (mean ± SE) in liver (6.18 ± 0.86) and muscle (1.12 ± 0.06) tissue that increased with size and age. Mercury concentrations were highest in fish caught off Florida's Atlantic coast, but varied on a finer regional scale. Mercury concentrations in muscle tissue were generally greater near urbanized areas with known mercury sources and environmental conditions appropriate for higher methylation rates. This suggests that management should consider improving the water quality in these areas to reduce the risk of health effects to human consumers and to the fish themselves.
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