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Mercury, arsenic, cadmium and lead in two commercial shark species (Sphyrna lewini and Caraharinus porosus) in Trinidad and Tobago Полный текст
2017
Mohammed, Azad | Mohammed, Terry
Sharks are long-lived apex predators which can accumulate toxic metals such as mercury and arsenic. Samples of Sphyrna lewini and Carcharinus porosus were collected from two commercial fish landing sites in Trinidad. Heavy metal concentrations were determined in the muscle, dorsal fin, vertebrae and liver using atomic absorption spectrometric. The provisional tolerable weekly intake (PTWI) and target hazard quotient (THQ) were determined to assess the potential health risks to consumers. Mercury levels ranged between 74–1899μg/kg in S. lewini and 67–3268μg/kg in C. porosus. Arsenic levels ranged between 144–2309μg/kg in S. lewini and 762–6155μg/kg in C. porosus. Cadmium levels generally ranged between 0.27–27.29mg/kg in S. lewini and 0.6–29.89mg/kg in C. porosus. Lead levels generally ranged between 0.14 and 208.81mg/kg in S. lewini while C. porosus levels ranged between 0.30 and 459.94mg/kg. The PTWI and THQ values suggest that consumption of these shark species can therefore be a major source of exposure to lead, cadmium, arsenic and mercury in humans and is likely to have potential health risk over long term exposure.
Показать больше [+] Меньше [-]Identifying the source of petroleum pollution in sediment cores of southwest of the Caspian Sea using chemical fingerprinting of aliphatic and alicyclic hydrocarbons Полный текст
2017
Shirneshan, Golshan | Bakhtiari, Alireza Riyahi | Memariani, Mahmoud
In this study, the concentration and sources of aliphatic and petroleum markers were investigated in 105 samples of Anzali, Rezvanshahr and Astara cores from the southwest of Caspian Sea. Petroleum importation was diagnosed as a main source in most depths of cores by the results of unresolved complex mixture, carbon preference index and hopanes and steranes. From the chemical diagnostic parameters, petroleum inputs in sediment of cores were determined to be different during years and the sources of hydrocarbons in some sections differed than Anzali and Turkmenistan and Azerbaijan oils. Diagenic ratios in most sediments of upper and middle sections in Astara core were determined to be highly similar to those of Azerbaijan oil, while the presence of Turkmenistan and Anzali oils were detected in a few sections of Anzali and Rezvanshahr cores and only five layers of downer section in Anzali core, respectively.
Показать больше [+] Меньше [-]Acute toxicity of organic antifouling biocides to phytoplankton Nitzschia pungens and zooplankton Artemia larvae Полный текст
2017
Jung, S.M. | Bae, J.S. | Kang, S.G. | Son, J.S. | Jeon, J.H. | Lee, H.J. | Jeon, J.Y. | Sidharthan, M. | Ryu, SH | Shin, H.W.
The toxicity of the antifouling biocides Irgarol 1051, Diuron, Chlorothalonil, Dichlofluanid, Sea-nine 211, Copper pyrithione, Zinc pyrithione, Ziram and Zineb were evaluated on Nitzschia pungens and Artemia larvae. Results showed that EC50 for Irgarol 1051 was 0.586μgl−1 was the strongest effect on N. pungens following by Copper pyrithione (4.908μgl−1), Ziram (5.421μgl−1), Zinc pyrithione (5.513μgl−1), Diuron (6.640μgl−1), Zineb (232.249μgl−1), Sea-nine 211(267.368μgl−1), Chlorothalonil (360.963μgl−1) and Dichlofluanid (377.010μgl−1) in 96h. In Artemia larvae, the biocides were evaluated the LC50 for larval survivals at 48h. Sea-nine 211 and Copper pyrithione were 0.318 and 0.319mgl−1. Chlorothalonil, Zinc pyrithione and Ziram were 2.683, 3.147 and 4.778mgl−1. Irgarol 1051, Diuron, Zineb and Dichlofluanid were 9.734, 30.573, 41.170 and 154.944mgl−1. These results provide baseline data concerning the toxicity of antifouling biocides against marine environment.
Показать больше [+] Меньше [-]Talitrus saltator as a biomonitor: An assessment of trace element contamination on an urban coastline gradient Полный текст
2017
Morrison, Liam | Bennion, Matthew | McGrory, Ellen | Hurley, William | Johnson, M.P.
This study reports the first ever application of the trace element pollution index (TEPI) along a coastal, urban gradient using trace element concentrations (Ti, Mn, Co, Cu, As, Mo, Ag, Cd, Pb, Cr, Fe, Zn and Se) in the amphipod crustacean Talitrus saltator. Samples were collected from 10 sites in Galway Bay (Ireland) and concentrations of Pb showed the greatest spatial variation, likely due to the proximity of some sites to a former landfill and busy harbour. The TEPI used alongside the quartile method allowed for the assigning of sites to contamination level categories. Mapping these class levels allowed for straightforward visualisation of trace element contamination along the urban gradient. In addition, this study presents trace elements levels in T. saltator form the Atlantic Coast of Europe for the first time and the concentrations observed were comparatively lower than previously reported for T. saltator from the Baltic and Mediterranean seas.
Показать больше [+] Меньше [-]Ecological risk assessment of a coastal zone in Southern Vietnam: Spatial distribution and content of heavy metals in water and surface sediments of the Thi Vai Estuary and Can Gio Mangrove Forest Полный текст
2017
Costa-Böddeker, Sandra | Hoelzmann, Philipp | Thuyên, Lê Xuân | Huy, Hoang Duc | Nguyễn, Hoàng Anh | Richter, Otto | Schwalb, Antje
Enrichment of heavy metals was assessed in the Thi Vai Estuary and in the Can Gio Mangrove Forest (SE, Vietnam). Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn contents in water and in sediments were measured. Total organic carbon, nitrogen, phosphorus and C/N ratios were determined. Cu and Cr values were higher than threshold effect level of toxicity, while Ni exceeded probable effect level, indicating the risk of probable toxicity effects. Enrichment factors (EF), contamination factor (CF) and Geo-accumulation index (I-geo) were determined. CF reveals moderate to considerable pollution with Cr and Ni. EF suggests anthropogenic sources of Cr, Cu and Ni. I-geo indicates low contamination with Co, Cu and Zn and moderate contamination with Cr and Ni. Overall metal contents were lower than expected for this highly industrialized region, probably due to dilution, suggesting that erosion rates and hydrodynamics may also play a role in metal contents distribution.
Показать больше [+] Меньше [-]Ports and pests: Assessing the threat of aquatic invasive species introduced by maritime shipping activity in Cuba Полный текст
2017
O'Brien, Charleen E. | Johnston, Matthew W. | Kerstetter, David W.
Aquatic invasive species (AIS) are biological pollutants that cause detrimental ecological, economic, and human-health effects in their introduced communities. With increasing globalization through maritime trade, ports are vulnerable to AIS exposure via commercial vessels. The Cuban Port of Mariel is poised to become a competitive transshipment hub in the Caribbean and the intent of this study was to evaluate present and potential impacts AIS pose with the likely future increase in shipping activity. We utilized previous assessment frameworks and publicly accessible information to rank AIS by level of threat. Fifteen AIS were identified in Cuba and one, the Asian green mussel Perna viridis (Linnaeus, 1758), had repeated harmful economic impacts. Five species associated with trade partners of Port Mariel were considered potentially detrimental to Cuba if introduced through shipping routes. The results presented herein identify species of concern and emphasize the importance of prioritizing AIS prevention and management within Cuba.
Показать больше [+] Меньше [-]The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms Полный текст
2017
Kühn, Susanne | Werven, Van, Bernike | Oyen, Van, Albert | Meijboom, André | Bravo Rebolledo, Elisa L. | Franeker, Van, Jan A.
The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms
2017
Kühn, Susanne | Werven, Van, Bernike | Oyen, Van, Albert | Meijboom, André | Bravo Rebolledo, Elisa L. | Franeker, Van, Jan A.
In studies of plastic ingestion by marine wildlife, visual separation of plastic particles from gastrointestinal tracts or their dietary content can be challenging. Earlier studies have used solutions to dissolve organic materials leaving synthetic particles unaffected. However, insufficient tests have been conducted to ensure that different categories of consumer products partly degraded in the environment and/or in gastrointestinal tracts were not affected. In this study 63 synthetic materials and 11 other dietary items and non-plastic marine debris were tested. Irrespective of shape or preceding environmental history, most polymers resisted potassium hydroxide (KOH) solution, with the exceptions of cellulose acetate from cigarette filters, some biodegradable plastics and a single polyethylene sheet. Exposure of hard diet components and other marine debris showed variable results. In conclusion, the results confirm that usage of KOH solutions can be a useful approach in general quantitative studies of plastic ingestion by marine wildlife.
Показать больше [+] Меньше [-]The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms Полный текст
2017
Kuhn, Susanne | van Werven, Bernike | van Oyen, Albert | Meijboom, André | Bravo Rebolledo, Elisa L. | van Franeker, Jan A.
In studies of plastic ingestion by marine wildlife, visual separation of plastic particles from gastrointestinal tracts or their dietary content can be challenging. Earlier studies have used solutions to dissolve organic materials leaving synthetic particles unaffected. However, insufficient tests have been conducted to ensure that different categories of consumer products partly degraded in the environment and/or in gastrointestinal tracts were not affected. In this study 63 synthetic materials and 11 other dietary items and non-plastic marine debris were tested. Irrespective of shape or preceding environmental history, most polymers resisted potassium hydroxide (KOH) solution, with the exceptions of cellulose acetate from cigarette filters, some biodegradable plastics and a single polyethylene sheet. Exposure of hard diet components and other marine debris showed variable results. In conclusion, the results confirm that usage of KOH solutions can be a useful approach in general quantitative studies of plastic ingestion by marine wildlife.
Показать больше [+] Меньше [-]Spatiotemporal variations in metal accumulation, RNA/DNA ratio and energy reserve in Perna viridis transplanted along a marine pollution gradient in Hong Kong Полный текст
2017
Yeung, Jamius W.Y. | Zhou, Guang-Jie | Leung, Kenneth M.Y.
We examined spatiotemporal variations of metal levels and three growth related biomarkers, i.e., RNA/DNA ratio (RD), total energy reserve (Et) and condition index (CI), in green-lipped mussels Perna viridis transplanted into five locations along a pollution gradient in the marine environment of Hong Kong over 120days of deployment. There were significant differences in metal levels and biomarker responses among the five sites and six time points. Mussels in two clean sites displayed better CI and significantly lower levels of Ag, Cu, Pb and Zn in their tissues than the other sites. Temporal patterns of RD in P. viridis were found to be site-specific. Across all sites, Et decreased in P. viridis over the deployment period, though the rate of decrease varied significantly among the sites. Therefore, temporal variation of biomarkers should be taken to consideration in mussel-watch programs because such information can help discriminate pollution-induced change from natural variation.
Показать больше [+] Меньше [-]Trace metals in sediments and benthic animals from aquaculture ponds near a mangrove wetland in Southern China Полный текст
2017
Wu, Hao | Liu, Jinling | Bi, Xiangyang | Lin, Guanghui | Feng, Christopher C | Li, Zhengjie | Qi, Fei | Zheng, Tianling | Xie, Liqi
In this study, we measured the concentrations of trace metals (Cr, Cu, Zn, As, Cd, Pb and Hg) in typical cultured animals (crabs, clams, and shrimps) and sediments from aquaculture ponds nearby mangrove wetlands in Zhangjiang estuary, China. The contents of Cr, Cu, Cd, and Pb in mangrove sediments were significantly higher than those in pond sediments, while an inverse distribution was observed for Zn, As, and Hg. Significantly higher concentrations of trace metals were found in clams from the mangrove mudflats compared to those from the aquaculture ponds. The sources of trace metals in the clams were primarily from organic fertilizer, whereas those in the shrimp were from contaminated sediment. The results of geo-accumulation index and the ecological risk assessment indicated that the aquaculture ponds near the mangrove wetlands in this subtropical estuary posed a special risk of endogenous and exogenous trace metal pollution to nearby systems.
Показать больше [+] Меньше [-]Modeling oil spill trajectory in Bosphorus for contingency planning Полный текст
2017
Bozkurtoğlu, Şafak Nur Ertürk
Bosphorus, is a strongly driven international maritime route between the Black Sea and the Sea of Marmara and is a high risk area for oil spill due to the heavy tanker traffic. In this study an oil spill trajectory model was developed for investigating the potential risks of accidental oil spills in Bosphorus. The proposed oil spill trajectory model combines the surface current velocity data obtained from a calibrated hydrodynamic model with the advection, spreading, and evaporation processes that are effective only on the sea surface and dominant for a couple of hours after the oil spill. Model simulations revealed that spilled oil reaches the shoreline on both sides of Bosphorus in <4h following the spill. We proposed locations for emergency intervention stations in Bosphorus which can be used to devise a suitable oil spill contingency plan to keep the adverse impacts of oil spills at minimum.
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