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991.
The globally distributed fallout radionuclide 137Cs was monitored in 25 resident and 22 migratory fish species collected from some regions of west and east coast of southern
India to establish a baseline data. The samples were collected during June 2008 to June 2009. Higher level of 137Cs was noted in planktivorous fishes and lower level in herbivores. A significant variation in 137Cs was observed between fishes with different feeding habits and different migratory pattern. Oceanodromic migratory fishes
displayed higher cesium levels than other migratory types. Similarly, migratory fishes displayed higher 137Cs concentration compared to resident fishes. The overall range of 137Cs varied from 0.06 to 0.3 Bq/kg in fishes. The biological concentration varied from 55 to 250. The average external dose
rate to fishes was calculated to be 2.7 × 10−7 μGy/h, while the internal dose rate varied from 8.50 × 10−6 to 5.27 × 10−5 μGy/h. The hazard quotient for fishes was found to be less than 1. The average intake of 137Cs via fishes to the public was calculated to be 3.5 Bq/year and subsequently the committed effective dose was 0.05 μSv/year.
The data obtained were less than global average and comparable to those of many regions. 相似文献
992.
Five-year monitoring study of chemical characteristics of Wet atmospheric precipitation in the southern region of Jordan 总被引:1,自引:0,他引:1
Omar Ali Al-Khashman Aiman Qasem Jaradat Elias Salameh 《Environmental monitoring and assessment》2013,185(7):5715-5727
Wet atmospheric samples were collected from different locations in the southern region of Jordan during a 5-year period (October 2006 to May 2011). All samples were analyzed for pH, EC, major ions (Ca2+, Mg2+, Na+, K+, HCO3 ?, Cl?, NO3 ?, and SO4 2?), and trace metals (Fe2+, Al3+,Cu2+, Pb2+, and Zn2+). The highest ion concentrations were observed during the beginning of the rainfall events because large amounts of dust accumulated in the atmosphere during dry periods and were scavenged by rain. The rainwater in the study area is characterized by low salinity and neutral pH. The major ions found in rainwater followed the order of HCO3?>?Cl??>?SO4 2? and Ca2+?>?Na+ > Mg2+ > NH4 + > K+. Trace metals were identified to be of anthropogenic origin resulting from cement and phosphate mining activities located within the investigated area and from heating activities during the cold period of the year (January to April). The wet precipitation chemistry was analyzed using factor component analysis for possible sources of the measured species. Factor analysis (principal component analysis) was used to assess the relationships between the concentrations of the studied ions and their sources. Factor 1 represents the contribution of ions from local anthropogenic activities, factor 2 represents the contribution of ions from natural sources, and factor 3 suggests biomass burning and anthropogenic source. Overall, the results revealed that rainwater chemistry is strongly influenced by local anthropogenic sources rather than natural and marine sources, which is in a good agreement with the results obtained by other studies conducted in similar sites around the world. 相似文献
993.
Application of multivariate statistical approach to identify heavy metal sources in bottom soil of the Seyhan River (Adana), Turkey 总被引:1,自引:0,他引:1
M. Gurhan Yalcin Ali Tumuklu Mustafa Sonmez Dilek Satir Erdag 《Environmental monitoring and assessment》2010,164(1-4):311-322
In this study, freshly deposited soils were sampled from the Seyhan River (Turkey) from the exit of the Seyhan Dam to the Adana exit. Heavy metal contents were measured with X-ray fluorescence spectrometer. Multivariate statistical approach is used to identify the sources of heavy metals and other elements in soil samples. Considering the size of anomalies, metals are ranked as Co>Pb>Cr>Zn>Al. Based on the hierarchical cluster analysis results, three clusters were observed. P, Mg, Ti, Fe, Ca, Na, K, Al, Si, and Nb form the first cluster, Zn, Sr, Pb, and Cr associated as the second cluster, and Ba and Co form the third cluster. Three factors computed from principal component analysis are explained with a cumulative variance of 95%. The first factor is defined with “high background lithogenic factor” Co, the second factor with “local industrial factor” Pb, Cr, Ba, and Mg, and the third factor with “natural factor” Cr and Pb. 相似文献
994.
Mohammad Ali Hamzeh Majid Shah-hosseini Abdolmajid Naderi Beni 《Environmental monitoring and assessment》2013,185(2):1791-1807
In this study, the levels of natural and anthropogenic metal contamination (aluminum (Al), iron (Fe), manganese (Mn), arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn)) in surface sediments of three harbors along the Iranian coast of Gulf of Oman were examined and reported for the first time. Effect of grain size, mineralogy, normalization technique using Fe concentrations, and different sediment quality guidelines were discussed. Data from the harbors were compared with other harbors worldwide. Sediments inside the harbors are characterized by moderate and high levels of pollution by trace metals Cu (12–287 μg/g), Pb (11–1,780 μg/g), Zn (38–547 μg/g), Cr (70–2,370 μg/g), and Ni (31–116 μg/g). However, As and Cd did not show considerable pollution inside and outside the harbors. Considering that there is no industrial activity around the study harbors, the major sources of contamination in the harbors are repairing, fueling, greasing, and painting of fishing ships and boats. Mineralogy of sediments in the study area as well as trace metal concentration in reference samples taken from onshore geological units confirmed that natural inputs of Cd, Cu, Pb, and Zn in the harbors are very low while most of Ni and Cr contamination in the study area comes from erosion of ophiolitic mélange units at the North of Makran mountains. 相似文献
995.
Singh K Singh DP Dixit CK Singh N Sharma C Sahai S Jha AK Kumari M Khan ZH Gupta PK 《Environmental monitoring and assessment》2012,184(7):4553-4564
A field campaign on aerosol chemical properties and trace gases measurements was carried out along the Delhi-Hyderabad-Delhi road corridor (spanning about 3,200 km) in India, during February 1-29, 2004. Aerosol particles were collected on quartz and cellulose filters using high volume (PM(10)) sampler at various locations along the route (i.e., urban, semi-urban, rural, and forest areas) and have been characterized for major cations (Na(+), Ca(2+), Mg(2+), K(+), and NH (4) (+)), anions (Cl(-), NO (3)(-), and SO (4)(2-)), and heavy metals (Cu, Cd, Fe, Zn, Mn, and Pb). Simultaneously, we measured NO(2) and SO(2) gases. These species show large spatial and temporal variations. The ambient PM(10) concentration has been observed to be the highest (55 ± 4 μg m(-3)) near semi-urban areas followed by forest areas (48 ± 2 μg m(-3)) and in rural areas (44 ± 22 μg m(-3)). The concentrations of NO( x ) (NO(2)+NO) and SO(2) ranged from 16 to 69 μg m(-3) and 4 to 11 μg m(-3), respectively. Among anions, NO(3)(-) and SO(4) (2-) are the major constituents of PM(10). The urban and semi-urban sites showed enhanced concentrations of Fe, Zn, Mn, Cd, and Pb. This study provide information about atmospheric concentrations of various species in the northern to central India, which may be important for policy makers to better understand the air quality of the region. 相似文献
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Md. Firoz Khan Yuichiro Shirasuna Koichiro Hirano Shigeki Masunaga 《Environmental monitoring and assessment》2010,171(1-4):441-456
This article analyses elemental composition of suspended particulate matter (SPM) samples collected monthly from 1999 to 2005 at two locations in Yokohama, Japan. Microwave digestion and inductively coupled plasma mass spectroscopy was employed to measure Mg, Al, Ca, V, Cr, Mn, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Ag, Cd, Cs, Ba, Pb, and Bi. Water-soluble ions (Na?+?, NH4 ?+?, K?+?, Ca2?+?, Cl???, NO3 ???, and SO4 2???) and carbonaceous mass (elemental and organic carbon) were detected using ion chromatograph and CHN analyzer, respectively. The results indicate that the composition of SPM on one of the sites is determined by automobile emissions and on the other by industrial combustions. The impact of the emission regulations for automobiles in large Japanese cities, which were enacted during 2002 and 2003, on the SPM composition of the samples is also studied. 相似文献