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Potential thyroid carcinogens in atmospheric emissions from industrial facilities in Manizales, a midsize Andean city in Colombia
2017
Arias-Ortiz, N.E. | Ruiz-Rudolph, P.
Manizales is a city in Colombia that presents high rates of thyroid cancer. It has a medium industrial development and there are concerns of the impact of their emissions on health, particularly on thyroid cancer. In this paper we characterize the geographical pattern of industrial atmospheric emissions of suspected thyroid carcinogens.We systematized data of industries in two groups. First, those with reports of atmospheric emissions of suspected thyroid carcinogens (reporting facilities – RFs), and then, industries not required to report or facilities with no-available emissions data but belonging to the same SIC-codes than RFs (nonreporting facilities – non-RFs). For non-RFs, annual average atmospheric emissions were estimated using a per-employee algorithm. The spatial pattern of sources emitting carcinogens was represented by plotting facilities by size and amounts of specific pollutants released.We found 11 RFs and 25 non-RFs in urban Manizales. RFs belong to the metalworking industries, plastics & rubber, manufacture of electrical and electronic devices, waste incineration, cremation, and meat production. Most of them were concentrated in the southeast of the city. Several RFs reported atmospheric emissions of carcinogens exceeding maximum permitted emission limits set in Colombian law. Most of non-RFs were micro and small industries, and were clustered in the southeast of the city and along the main road axis.We found clusters of pollution sources near densely populated areas. Thyroid cancer incidence might be greater in areas closer to industries than in furthest areas. We will submit a paper that studies this hypothesis soon.
Показать больше [+] Меньше [-]Assessing the toxicity of triphenyltin to different life stages of the marine medaka Oryzias melastigma through a series of life-cycle based experiments
2017
Yi, Xianliang | Leung, Kenneth M.Y.
Toxic effects of triphenyltin (TPT) to different life stages of the marine medaka Oryzias melastigma were investigated through a series of life-cycle based exposure experiments. In embryo stage, TPT exposure could elevate the heartbeat rate at Day 6–8 post-fertilization and increase the expression levels of five heart development related genes (i.e., ATPase, COX2, BMP4, GATA4 and NKX2.5). In larval stage, TPT shortened the body length at ≥10μg/L and suppressed the swimming activity of the fish larvae at Day 1 post-hatching at 50μg/L. In reproductive stage, TPT exposure resulted in a male-biased sex ratio (2μg/L) and reduced the gonadosomatic index (GSI) in females (≥ 0.1μg/L), which might in turn lead to a decline in their population fitness. The reproductive stage of O. melastigma was more sensitive to TPT than other stages, while the GSI of female medaka was the most sensitive endpoint.
Показать больше [+] Меньше [-]An analysis of the spatial distribution of O3 and its precursors during summer in the urban atmosphere of Riyadh, Saudi Arabia
2017
Alharbi, Badr H. | Alduwais, Abdulilah K. | Alhudhodi, Abdulrahman H.
Ozone (O3) concentration, along with the concentrations of 10 precursors (acetone, toluene, ethylbenzene, benzene, xylenes, styrene, cyclohexane, NO, NO2, and CO), were measured and characterized at 16 locations in Riyadh, the capital city of Saudi Arabia, for the period of May through August 2012. The results showed that concentrations of all O3 precursors were high in central and industrial areas, owing mainly to road traffic volume and industrial emissions. Except for benzene, all pollutants featured a skewed distribution, which indicates that they might occasionally be influenced by contiguous sources of air pollution and/or by emissions from heavy air polluters. The benzene distribution does not follow this behavior, possibly due to the shortage of substantial stationary benzene emitters. Also, the considerable difference between the median and the mean of both xylene and toluene distributions suggests local emission impacts in Riyadh. O3 concentrations averaged 34.59 ± 24.17 ppb and were a maximum of 277.47 ppb, occasionally violating the 1-h national standard (120 ppb) and frequently exceeding World Health Organization (WHO) and United States Environmental Protection Agency (EPA) standards.
Показать больше [+] Меньше [-]Effects of short-term weathering on the stable carbon isotope compositions of crude oils and fuel oils
2017
Liu, Yu | Xu, Jixiang | Chen, Wenjing | Li, Ying
A short-term simulated weathering experiment was performed on two crude oils and two heavy fuel oils under natural conditions to evaluate the effects of natural weathering processes by using gas chromatography–mass spectrometry combined with gas chromatography–isotopic ratio mass spectrometry. The results of diagnostic ratios of n-alkanes show that only odd to even predominance (OEP1, OPE2) and carbon preference index (CPI) remain stabilized during the 28 d weathering process, but they cannot effectively distinguish the four types of oils. Statistical analyses based on paired sample t-test and principal component analysis (PCA) revealed that stable carbon isotope compositions of n-alkanes in the four studied oils have no significant changes over the weathering time, and that the carbon isotope discrimination (Δδ13C) of n-alkanes is <3‰. We have provided evidence that the stable carbon isotope compositions of n-alkanes compared to n-alkanes diagnostic ratios significantly improve the efficiency and fidelity of the oil fingerprint identification.
Показать больше [+] Меньше [-]Improving oil classification quality from oil spill fingerprint beyond six sigma approach
2017
Juahir, Hafizan | Ismail, Azimah | Mohamed, Saiful Bahri | Toriman, Mohd Ekhwan | Kassim, Azlina Md | Zain, Sharifuddin Md | Ahmad, Wan Kamaruzaman Wan | Wah, Wong Kok | Zali, Munirah Abdul | Retnam, Ananthy | Taib, Mohd. Zaki Mohd | Mokhtar, Mazlin
This study involves the use of quality engineering in oil spill classification based on oil spill fingerprinting from GC-FID and GC–MS employing the six-sigma approach. The oil spills are recovered from various water areas of Peninsular Malaysia and Sabah (East Malaysia). The study approach used six sigma methodologies that effectively serve as the problem solving in oil classification extracted from the complex mixtures of oil spilled dataset. The analysis of six sigma link with the quality engineering improved the organizational performance to achieve its objectivity of the environmental forensics. The study reveals that oil spills are discriminated into four groups' viz. diesel, hydrocarbon fuel oil (HFO), mixture oil lubricant and fuel oil (MOLFO) and waste oil (WO) according to the similarity of the intrinsic chemical properties. Through the validation, it confirmed that four discriminant component, diesel, hydrocarbon fuel oil (HFO), mixture oil lubricant and fuel oil (MOLFO) and waste oil (WO) dominate the oil types with a total variance of 99.51% with ANOVA giving Fstat>Fcritical at 95% confidence level and a Chi Square goodness test of 74.87. Results obtained from this study reveals that by employing six-sigma approach in a data-driven problem such as in the case of oil spill classification, good decision making can be expedited.
Показать больше [+] Меньше [-]Factor associated variations in the home range of a resident Adriatic common bottlenose dolphin population
2017
Rako-Gospić, Nikolina | Radulović, Marko | Vučur, Tihana | Pleslić, Grgur | Holcer, Draško | Mackelworth, Peter
This study investigates the influence of the most dominant factors (association patterns, gender, natal philopatry and anthropogenic pressure) on the home range size of the 44 most resident common bottlenose dolphins (Tursiops truncatus) inhabiting the waters of the Cres-Lošinj archipelago (north Adriatic Sea, Croatia), a recently declared NATURA 2000 SCI. Results show that variations in home range patterns (MCP, 95% KDE and 50% KDE home range size) among the individual resident dolphins are primarily related to differences in gender and reflect the way in which different genders respond to external stressors. In addition, results confirm the seasonal influence of nautical tourism on both female and male dolphins through changes in their home range sizes. The overall results improve current knowledge of the main anthropogenic threats that should be taken into consideration when developing conservation measures to be applied to this Cres and Lošinj SCI.
Показать больше [+] Меньше [-]Characterization of polychlorinated biphenyl congeners in surface sediments of the Changjiang Estuary and adjacent shelf by high-resolution sampling and high-resolution mass spectrometry
2017
Liu, Aifeng | Wang, Yawei | Xian, Mo | Zhao, Zongshan | Zhao, Bin | Wang, Jinpeng | Yao, Peng
Due to limited samples and low-resolution analysis, conflicting findings on major polychlorinated biphenyl (PCB) congeners and their origins remain in the East China Sea (ECS). Based on high-resolution sampling and high-resolution mass spectrometry analysis, 72 surface sediment samples from the Changjiang Estuary and adjacent ECS shelf were determined to characterize 39 PCB congeners. PCBs (∑39PCBs) ranged from 0.003 to 16.18ng/g dw, presenting a decreasing seaward trend. Tri-, tetra- and penta-CBs were the main components, accounting for >64% of ∑39PCBs in most samples. Tetra-CBs were the dominant congeners, corresponding to results of sediments from Changjiang middle reach and soils from Changjiang Delta. Comparison between PCBs and sediment properties indicated there may be a deposition boundary of 30°N. In the north, the spatial distribution of PCBs is controlled by Changjiang input and hydrodynamic conditions, while in the south closely related to combination of local source and riverine input.
Показать больше [+] Меньше [-]Spatial-temporal distribution and risk assessment of mercury in different fractions in surface sediments from the Yangtze River estuary
2017
Wang, Qingrui | Liu, Ruimin | Men, Cong | Xu, Fei | Guo, Lijia | Shen, Zhenyao
The temporal and spatial distributions of mercury in different fractions and its potential ecological risk were investigated in sediments from the Yangtze River estuary (YRE) by analyzing data collected from the study area. The results showed that mercury in the organic and residual fractions had dominant proportions, from 15.2% to 48.52% and from 45.96% to 81.59%, respectively. The fractions were more susceptible to seasonal changes than other fractions. Higher proportions of mercury in organic fraction were found in wet seasons; the opposite was true for mercury in residual fraction. With respect to the spatial distribution, the concentration mercury in exchangeable, carbonate and Fe-Mn oxide fractions showed a decreasing trend from the inner estuary to the outer estuary, but no obvious trends were found in the distributions of mercury in the organic and residual fractions. The risk assessment code (RAC) was used to evaluate the potential ecological risk in the study area based on the proportions of exchangeable and carbonate fractions. The average RAC values during the four periods were 6.00%, 2.20%, 2.83%, and 0.61%. Although these values show that the risk in the study area is generally low, the distribution of RAC values indicates that the inner estuary has a medium risk, with a value up to 10%.
Показать больше [+] Меньше [-]Distribution, enrichment and source of heavy metals in Rizhao offshore area, southeast Shandong Province
2017
Song, Hongying | Liu, Jinqing | Yin, Ping | Zhang, Yong
50 surface sediments were collected from Rizhao offshore area to determine heavy metals (Cu, Pb, Zn, Cr, Cd, As, Hg) pollution. High heavy metal values were located near the two ports in the north and south study areas, which was consistent with the distribution of fine-grained sediments. According to threshold effect level (TEL) and probable effect level (PEL), Cu and As had occasionally adverse biological effects on the aquatic ecosystems. The enrichment factor (EF) values showed that most of the study area was moderate or moderately severe enrichment for As, and minor enrichment for Pb, but Hg was only moderately enriched in the river estuaries. The sources of Cu, Zn and Cr were mainly influenced by natural weathering processes via the river inputs, whereas Pb, Cd and As were mainly derived from anthropogenic sources. Hg may have both natural and anthropogenic sources.
Показать больше [+] Меньше [-]Hepatocellular adenoma in a European flatfish (Limanda limanda): Genetic alterations in laser-capture micro-dissected tissue and global transcriptomic approach
2017
Lerebours, Adélaïde | Chapman, Emma | Lyons, Brett P. | Bignell, John P. | Stentiford, Grant D. | Rotchell, Jeanette M.
Liver tumours in flatfish have been diagnosed using histopathology for decades to monitor the impacts of marine pollution. Here we describe the application of specific gene (retinoblastoma, Rb) profiling in laser capture micro-dissected samples, and a suppression subtractive hybridization (SSH) approach to isolate differentially expressed genes in hepatocellular adenoma (HCA) samples from dab, Limanda limanda.The Rb profiles from apparently normal and HCA micro-dissected samples of fish from the North Sea showed no significant difference, and genotypic heterogeneity within defined histological phenotypes was observed. In the SSH, sequences associated with cell signalling, cell cycle, gene expression regulation, protein transport and protein degradation were isolated. These included up-regulation of arrestin domain containing 3 (arrdc3), Rac-1 and tribbles, and down-regulation of ankyrin repeat/sterile alpha-motif domain-containing protein 1B-like (ANKS1B-like), c-fos, CDKN1B and RhoA-like sequences, previously implicated in mammalian HCA. This study offers new candidates involved in fish liver tumour development.
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