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31.
Segara Anakan is a mangrove-fringed lagoon in Java, Indonesia, which is affected by human activities in the lagoon and its
hinterland. Nutrient and sediment input from the Citanduy River which drains an agriculture-dominated hinterland is thought
to be an important factor for ecosystem degradation. From dry and rainy season investigations of dissolved inorganic nutrients
between May 2004 and August 2006 we infer that the nutrient inventory of Segara Anakan is controlled by a complex mixture
of anthropogenic and natural sources and processes. Maximum inputs into the western lagoon were supplied by the Citanduy during
the rainy season while tidal exchange with the Indian Ocean dominated in the eastern lagoon with little freshwater input.
During the dry season recycling in mangroves appeared to be an additional source of nutrients to the lagoon. Despite an extremely
high population density and intensive agriculture in the hinterland nutrient pollution and eutrophication in the lagoon were
low to moderate on a global scale. It is probably due to the short residence time of water in the shallow lagoon which indicates
that major part of the land-derived nutrient input is rapidly exported to the sea. Although Segara Anakan is a highly perturbed
system for decades, it appears that still natural processes exert major control on the nutrient inventory of the lagoon. 相似文献
32.
Fourteen different types of Omani-made kohl were collected from different locations in Oman. The kohl samples were analyzed using different analytical techniques including X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray microanalysis, and inductively coupled plasma mass spectroscopy after sample digestion. The results show that six kohls (kohls 1–6) are mineral-based, four of which, namely lasif, cold ethmid, hot ethmid, and original ethmid, contain very high levels of Pb (basically galena). The other two kohls (red ethmid and black ethmid) contain mostly iron (hematite, magnetite, and goethite). The other kohl samples (kohls 7–14) are basically amorphous carbons, one of which is made by charring date stones while the rest are basically soot collected from burning different materials. Compared to the results obtained by inductively coupled plasma mass spectroscopy, energy-dispersive X-ray microanalysis yielded higher concentrations of major elements while some minor elements were not detected; this is probably related to some limitations in the latter technique. Based on this study, carbon-based kohls possess much lower levels of toxic elements than mineral-based kohls; consequently, the former can be considered as the less hazardous kohls. However, concerns about the use of soot in cosmetics are rising because of the presence of some carcinogenic compounds such as polyaromatic hydrocarbons in soot. 相似文献
33.
The presence of toxic heavy metals in the environment is considered as a risk factor for adverse human and environmental health effects. Farahabad Region is a tourist center in the southern coast of Caspian Sea in Mazandaran Province of Iran. Environmental monitoring of this site is important for public health for individuals visiting and residing in this region. Although numerous biomonitoring data are available globally, very few if any apparent investigations have been conducted in this region. In this study, concentration of three heavy metals chromium (Cr), lead (Pb), and cadmium (Cd) was determined for one year in Cladophora glomerata, the predominant macroalga species present in this region. Detection of heavy metals was performed with atomic absorption spectrophotometer using standard methods. Results showed that the range of Cr metal in various algal samples was 29–55 ppm/g dry weight. The levels of Pb in algal samples (Cladophora) ranged from 2 to 8 ppm/g dry weight. The Cd concentrations in C. glomerata biomass ranged from 1.5 to 8.2 ppm/g dry biomass. In view of potential threats of such high metal concentrations in coastal waters and in algal tissues, it is necessary to adopt conservation measures to ensure public health safety. 相似文献
34.
Bushra KhanLinda S. Lee 《Chemosphere》2012,89(11):1443-1449
The increasing size of concentrated animal feeding operations has led to a concomitant increase in the land-application of manure, which has spawned research on the concentrations and environmental risk assessment of natural and synthetic hormones in animal manures. 17β-Trenbolone acetate (TBA) is widely used in the United States for improving daily gains in beef cattle and is often administered in combination with 17β-estradiol (17β-E2). Trenbolone (TB) and E2 isomers and their metabolites were quantified in manure collection pits and lagoon effluent from beef cattle implanted with the commercial anabolic preparation Ravoler-S (containing 140 mg 17β-trenbolone acetate and 28 mg 17β-E2). Manure pit and lagoon effluent samples were collected weekly for 9 weeks post implanting and analyzed using reverse-phase liquid chromatography tandem mass spectrometry. 17α-TB was the most abundant androgen with the highest concentration observed 2 weeks post implant. 17β-TB and trendione peaked at the end of week 2 and 4, respectively. For the estrogens, the highest concentrations for estrone (E1), estriol (E3), and 17α-E2 were observed after week 4, 6, and 8, respectively. 17β-E2 concentrations were the lowest of the estrogens and erratic over time. In lagoon water, which is used for irrigation, 17α-TB and E1 had the highest detected hormone concentrations (1.53 and 1.72 μg L−1, respectively). Assuming a 1-2 order dilution during transport to surface water, these hormone levels could lead to concentrations in receiving waters that exceed some of the lowest observable effect levels (LOELs) reported for hormones (e.g., 0.01-0.03 μg L−1). 相似文献
35.
Ishtiaq Muhammad Jehan Noor Khan Said Akbar Muhammad Said Saddique Umar Iftikhar Bushra Zahidullah 《Environmental science and pollution research international》2018,25(15):14666-14673
Environmental Science and Pollution Research - This study was aimed to investigate the potential harmful element (PHE) concentrations in coal dust and evaluate the human risk assessment and health... 相似文献
36.
Anser Muhammad Khalid Usman Bushra Hyder Shabir Nassani Abdelmohsen A. Askar Sameh E. Zaman Khalid Abro Muhammad Moinuddin Qazi 《Environmental science and pollution research international》2021,28(36):49820-49832
Environmental Science and Pollution Research - The study’s objective is to evaluate the impact of environmental sustainability rating, financial development, changes in the price level and... 相似文献
37.
Studies on lethal concentrations and toxicity stress of some xenobiotics on aquatic organisms 总被引:1,自引:0,他引:1
Three widely used xenobiotics pentachlorophenol (PCP), 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-chloro-2,6-diethyl-N-(butoxymethyl) acetanilide (Butachlor) are evaluated for acute toxicity and stress behavior on freshwater fish (Heteropneustes fossilis, Clarias batrachus, Channa punctatus) and mosquito larvae (Culex pipiens fatigans). The experiment was carried out by medium treatment using intermittent flow-through system. Median lethal concentrations (LC50) were calculated by probit analysis. The LC50 values and 95% confidence intervals showed variable range for tested chemicals. Mosquito larvae generally appeared resistant than fish, while H. fossilis was found to be most sensitive. Stress signs in the form of behavioral changes are also observed. Both types of organisms are recommended as good bioindicator for the risk assessment of aquatic environment due to chemicals tested. 相似文献
38.
Maria Sabeen Abdol Ghaffar Ebadi Zulfiqar Ahmad Bhatti Faridullah Muhammad Irshad 《毒物与环境化学》2019,101(7-8)
Statement of RetractionWe, the Editors and Publisher of Toxicological & Environmental Chemistry, have retracted the following article:Maria Sabeen, Qaisar Mahmood, Abdol Ghaffar Ebadi, Zulfiqar Ahmad Bhatti, Faridullah, Muhammad Irshad, Allauddin Kakar, Muhammad Bilal, Hafiz Muhammad Arshad and Naeem Shahid, ‘Consequences of health risk assessment of wastewater irrigation in Pakistan Israel Affairs’, Toxicological & Environmental Chemistry, 2019, DOI: 10.1080/02772248.2019.1619335The article is retracted due to the oversights that were made during peer review process that resulted in the article being published online in error. Further review from independent reviewers was sought. This confirmed that the central findings and methodology of the study in question are unreliable and therefore unsuitable for publication.We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions.The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as “Retracted”. 相似文献
39.
AbstractContinuous monitoring of water quality of freshwater bodies may prevent outbreak of diseases and occurrence of hazards through employment of effective protection measures. The aim of the current investigation was to determine occurrence of water and sediment pollution in Tajan River North Iran which ultimately may be a threat to recreational beaches of Caspian Sea. Water samples were analyzed for various physicochemical parameters including pH, electrical conductivity (EC), total dissolved solids (TDS), bicarbonates, sulfates, cations, chlorides and heavy metals. The concentrations of zinc (Zn), cadmium (Cd), chromium (Cr) and lead (Pb) were determined using atomic absorption spectroscopy. Similarly, sediment samples were assessed for physicochemical characteristics including pH, EC, saturation percentage, organic matter, organic carbon, texture and cations. Overall, pH, EC, organic matter, and cation values were within acceptable limits according to USEPA water quality guidelines. However, phosphorus (P) concentration up to 5.6?mg/L was considered as “unsafe” which might result in undesirable eutrophication and increased accumulation of sediment organic content leading to excessive growth of algal species in riverine ecosystem. Heavy metal concentrations of Cd (0.08?ppm) and Pb (3?ppm) were above USEPA threshold limits which may consequently affect sustainability of Tajan River. The unacceptable levels of Cd, Pb and P may produce eutrophication of Caspian Sea coasts and damage the ecosystem. 相似文献
40.
Bibi Noorina Sayed Murtaza Shah Noor S. Rehman Faiza Naeem Abdul Mahmood Tahira Hussain Sajjad Iqbal Jibran Gul Ikhtiar Gul Saman Bushra Maleeha 《Environmental science and pollution research international》2022,29(42):63041-63056
Environmental Science and Pollution Research - Binary composite of zerovalent iron and titanium dioxide (Fe0/TiO2) was synthesized for the catalytic removal of dichlorophene (DCP) in the presence... 相似文献