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National inventory of mercury release into different phase media estimated by UNEP Toolkit in South Korea Full text
2014
Pudasainee, Deepak | Seo, Yong-Chil | Kim, David Junghoon | Hong, Ji-Hyung | Park, Jung-Min
This paper summarizes the national inventory of mercury release into all media (air, water, land, impurity in products, general wastes and sector specific disposal) from South Korea, using UNEP mercury Toolkit. Total mercury input and release, distribution into different media, major contributors by source categories are discussed. The total quantified mercury release into different phase media was 284.0 t/y and 281.3 t/y in Level 1 and 2 estimation, respectively. Mercury release from primary metal production, waste incineration, extraction and use of fuels/energy sources were dominant. The replacement of output distribution factors in the Toolkit by real data from mass balance study in the anthropogenic sources resulted decrease in the share of mercury emission into air from 20.6% to 9.6%. Comparison of mercury releases into the atmosphere estimated by the Toolkit Level 2 with real distribution factors data and our earlier estimation with measurements in the selected industries showed only a little discrepancy, with reasonable variation. These differences are due to the use of efficient process technology and air pollution control devices. Since most mercury is released in waste and byproducts, recovery and safe storage issues are to be emphasized in the future studies.
Show more [+] Less [-]Marine phytoplankton motility sensor integrated into a microfluidic chip for high-throughput pollutant toxicity assessment Full text
2014
Zheng, Guo-xia | Li, Ya-jie | Qi, Lin-lin | Liu, Xian-ming | Wang, Hu | Yu, Shu-ping | Wang, Yun-hua
A microfluidic chip was designed to assess the toxicity of pollutants in a high-throughput way by using marine phytoplankton motility as a sensor signal. In this chip, multiple gradient generators (CGGs) with diffusible chambers enable large scale of dose-response bioassays to be performed in a simple way. Two mobile marine phytoplankton cells were confined on-chip and stimulated by 8 concentrations (generated by CGG) of Hg, Pb, Cu and phenol singly, as well as Cu and phenol jointly. CASA system was used to characterize motility by motile percentage (%MOT), curvilinear velocity (VCL), average path velocity (VAP) and straight line velocity (VSL). In all cases, dose-dependent inhibitions of motility were observed. In the present system, only 2h was needed to predict EC50. Thus, the developed microfluidic chip device was proved to be useful as a rapid/simple and high-throughput test method in marine pollution toxicity assessment.
Show more [+] Less [-]Underwater noise pollution in a coastal tropical environment Full text
2014
Bittencourt, L. | Carvalho, R.R. | Lailson-Brito, J. | Azevedo, A.F.
Underwater noise pollution has become a major concern in marine habitats. Guanabara Bay, southeastern Brazil, is an impacted area of economic importance with constant vessel traffic. One hundred acoustic recording sessions took place over ten locations. Sound sources operating within 1km radius of each location were quantified during recordings. The highest mean sound pressure level near the surface was 111.56±9.0dB re 1μPa at the frequency band of 187Hz. Above 15kHz, the highest mean sound pressure level was 76.21±8.3dB re 1μPa at the frequency 15.89kHz. Noise levels correlated with number of operating vessels and vessel traffic composition influenced noise profiles. Shipping locations had the highest noise levels, while small vessels locations had the lowest noise levels. Guanabara Bay showed noise pollution similar to that of other impacted coastal regions, which is related to shipping and vessel traffic.
Show more [+] Less [-]Selenium and mercury concentrations in harbor seals (Phoca vitulina) from central California: Health implications in an urbanized estuary Full text
2014
McHuron, Elizabeth A. | Harvey, James T. | Castellini, J Margaret | Stricker, Craig A. | O’Hara, Todd M.
We measured total selenium and total mercury concentrations ([TSe] and [THg]) in hair (n=138) and blood (n=73) of harbor seals (Phoca vitulina) from California to assess variation by geography and sex, and inferred feeding relationships based on carbon, nitrogen, and sulfur stable isotopes. Harbor seals from Hg-contaminated sites had significantly greater [THg], and lesser [TSe] and TSe:THg molar ratios than seals from a relatively uncontaminated site. Males had significantly greater [THg] than females at all locations. Sulfur stable isotope values explained approximately 25% of the variability in [THg], indicating increased Hg exposure for seals with a greater use of estuarine prey species. Decreased [TSe] in harbor seals from Hg-contaminated regions may indicate a relative Se deficiency to mitigate the toxic effects of Hg. Further investigation into the Se status and the potential negative impact of Hg on harbor seals from Hg-contaminated sites is warranted.
Show more [+] Less [-]The impact of water temperature on water quality indexes in north of Liaodong Bay Full text
2014
Kong, Xiangpeng | Ye, Shuhong
The north of Liaodong Bay is one of the most severely polluted areas in Bohai Sea. Because the self-purification capacity from the sea water exchange process is limited, the pollutants from the land and river sources cannot be completed degraded and an obviously contaminated zone was formed in the north of Liaodong Bay. Therefore the self-purification capacity from biological process is essential for maintaining ecosystem balance. Marine heterotrophic bacteria play an important role in degradation of the dissolved organic matters and constitution of the primary production in the coastal areas. The shift of water temperature between winter and summer is about 28°C in the north of Liaodong Bay, which causes changes in the self-purification capacity of the sea area. Certain indexes of water quality in Liaodong Bay were investigated in order to detect how these indexes response to the changing of water temperature. The experimental results show that COD, DO and the concentration of fecal coliform vary a little with the changing of water temperature; TBC increases dramatically when the water temperature is over 16°C; and TBC in summer is 30 times more than that in winter. By this study, the paper provides a reference to assess the environmental purification capacity of the sea area during different seasons.
Show more [+] Less [-]Detection of macroalgae blooms by complex SAR imagery Full text
2014
Shen, Hui | Perrie, William | Liu, Qingrong | He, Yijun
Increased frequency and enhanced damage to the marine environment and to human society caused by green macroalgae blooms demand improved high-resolution early detection methods. Conventional satellite remote sensing methods via spectra radiometers do not work in cloud-covered areas, and therefore cannot meet these demands for operational applications. We present a methodology for green macroalgae bloom detection based on RADARSAT-2 synthetic aperture radar (SAR) images. Green macroalgae patches exhibit different polarimetric characteristics compared to the open ocean surface, in both the amplitude and phase domains of SAR-measured complex radar backscatter returns. In this study, new index factors are defined which have opposite signs in green macroalgae-covered areas, compared to the open water surface. These index factors enable unsupervised detection from SAR images, providing a high-resolution new tool for detection of green macroalgae blooms, which can potentially contribute to a better understanding of the mechanisms related to outbreaks of green macroalgae blooms in coastal areas throughout the world ocean.
Show more [+] Less [-]Enrichment and partitioning of polycyclic aromatic hydrocarbons in the sea surface microlayer and subsurface water along the coast of Xiamen Island, China Full text
2014
Ya, Miao-Lei | Wang, Xin-Hong | Wu, Yu-Ling | Ye, Cui-Xing | Li, Yong-Yu
Sea microlayer (SML) and subsurface water (SSW) samples were collected around Xiamen Island to study the enrichment and partitioning of polycyclic aromatic hydrocarbons (PAHs). Total PAH concentrations ranged from 93.43 to 411.05ng L−1 in the SML and 49.29–279.42ng L−1 in the SSW. Compared with the results of previous studies before pollution control measurements, PAHs levels decreased significantly. The enrichment factors (EFs) of dissolved and particulate PAHs varied from 0.68 to 2.71 and 0.43–3.56. EFs showed the consistent enrichment trends with sites and exhibited different enrichment characteristics between 2 and 3 ring PAHs and 4 ring PAHs. Furthermore, the much higher concentrations of BaP (strong carcinogenicity) were accompanied by higher EFs in the SML samples from the Western Xiamen Harbour, which together indicated the risk of impacts to the fish eggs that usually float on the SML water after exposure to oil spills and combustion, contributed directly by the port and shipping activities.
Show more [+] Less [-]Metals and metalloids in whole blood and tissues of Olive Ridley turtles (Lepidochelys olivacea) from La Escobilla Beach (Oaxaca, Mexico) Full text
2014
Cortés-Gómez, Adriana A. | Fuentes-Mascorro, Gisela | Romero, Diego
Concentrations of eight metals and metalloids (Pb, Cd, Cu, Zn, Mn, Se, Ni and As) were evaluated from 41 nesting females (blood) and 13 dead (tissues) Olive Ridley turtles (Lepidochelys olivacea), a species classified as vulnerable and also listed in Appendix I of the Convention of International Trade in Endangered Species (CITES). The mean blood, liver and kidney lead concentration were 0.02±0.01, 0.11±0.08 and 0.06±0.03μgg−1 ww respectively, values lower than other turtle species and locations, which it could be due to the gradual disuse of leaded gasoline in Mexico and Central America since the 1990s. Mean concentration of cadmium was 0.17±0.08 (blood), 82.88±36.65 (liver) and 150.88±110.99μgg−1 (kidney). To our knowledge, the mean renal cadmium levels found is the highest ever reported worldwide for any sea turtle species, while other six elements showed a concentration similar to other studies in sea turtles.
Show more [+] Less [-]Source identification of heavy metal contamination using metal association and Pb isotopes in Ulsan Bay sediments, East Sea, Korea Full text
2014
Chae, Jung Sun | Choi, Man Sik | Song, Yun Ho | Um, In Kwon | Kim, Jae Gon
To determine the characteristics of metal pollution sources in Ulsan Bay, East Sea, 39 surface and nine core sediments were collected within the bay and offshore area, and analyzed for metals and stable lead (Pb) isotopes.Most surface sediments (>95% from 48 sites) had high copper (Cu), zinc (Zn), cadmium (Cd), and Pb concentrations that were as much as 1.3 times higher than background values. The primary source of metal contamination came from activities related to nonferrous metal refineries near Onsan Harbor, and the next largest source was from shipbuilding companies located at the mouth of the Taehwa River. Three different anthropogenic sources and background sediments could be identified as end-members using Pb isotopes. Isotopic ratios for the anthropogenic Pb revealed that the sources were imported ores from Australia, Peru, and the United States. In addition, Pb isotopes of anthropogenic Pb discharged from Ulsan Bay toward offshore could be determined.
Show more [+] Less [-]Mercury in Caribbean dolphins (Stenella longirostris and Stenella frontalis) caught for human consumption off St. Vincent, West Indies Full text
2014
Fielding, Russell | Evans, David W.
The island of St. Vincent in the Lesser Antilles supports an ongoing, legal cetacean hunt, which targets several species for human consumption. Little is known regarding the healthfulness and potential health risks of these foods in this setting. Following established methodologies we analyzed 39 raw muscle tissue samples and 38 raw blubber samples from two cetacean species for total mercury and methyl-mercury. We also analyzed samples of muscle tissue from an unknown cetacean species prepared for consumption. We report high concentrations of total mercury and methyl-mercury in these tissues as compared to published data for other seafood products. Further, our findings indicate that the traditional preparation method most often used locally in St. Vincent yields a finished food product with a much higher mercury concentration than the unprocessed tissue. Our results highlight the potential for negative human health effects related to the consumption of these food products in St. Vincent.
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