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21.
Stigmastane and hopanes as conserved biomarkers for estimating oil biodegradation in a former refinery plant-contaminated soil 总被引:1,自引:0,他引:1
In the last decade, a refinery plant located in Lido Adriano, East Ravenna (Italy) has been subject to mineral oil contamination. The mineral crude oil, extracted from the offshore in Adriatic sea, consisted of 78% aliphatics, cyclic alkanes and saturated polycyclic hydrocarbons, 9% aromatics, polycyclic aromatic hydrocarbons (PAHs) and alkylated derivatives, and 13% of tars/asphaltenes. Analysis of soil after 10 years of natural attenuation revealed a complete depletion of linear (n-C(9)-C(24)), light aromatics (C1-C3/benzenes) and PAHs (C2/naphthalene, C1/phenanthrene); besides a substantial degradation of isoprenoids prystane and phytane, branched and cyclic alkanes. The remaining contaminants which withstood to natural degradation was saturated polycyclic hydrocarbons (perhydro-PAH derivatives), unsaturated polycyclic hydrocarbons (tetrahydro, dihydro-PAH derivatives), terpanes, steranes and unidentified compounds. Such residues resulted in 80% reduction of its concentration after two months of laboratory treatment. Samples were extracted by organic solvents, separated by silica/alumina gel column chromatography and analyzed by gas chromatography-mass selective detector (GC-MSD). Identification and quantification of aliphatic, cyclic alkanes, typical PAHs, terpanes and steranes were carried out to chromatograms of M/Z=85, 83, individual M/Zs, M/Z=191 and 217, respectively. The present work shows that, among numerous biomarkers present in the source oil, stigmastane and two isomers of hopane showed invariable concentrations after laboratory experiments that mimic natural biodegradation in the field, so they can be used as conserved internal biomarkers. These are very useful tools to assess alterations in less stable classes of saturated compounds contained in petroleum. Marked degradation of perhydro, tetrahydro, dihydro-PAH derivatives in the laboratory treatment has been evidenced. 相似文献
22.
Urban wastewater treatment plant efficiency, as well as biosolid quality, depends on urban wastewater quality, which can be affected by non domestic discharges (industrial, commercial etc.). The characterization of wastewater quality and non domestic discharge is complex, expensive and time consuming. However, these discharges must be controlled and reduced if possible. The development of a simple and fast methodology, namely based on alternative methods such as UV spectrophotometry, has been carried out and applied to different areas of a medium sized town of Southern Québec (Canada). Several autosamplers and on line/on site measurements have been used in critical control points of the network areas, for a dry weather campaign in four areas (industrial, commercial, hospital and university). The flow rate study, completed by the exploitation of conductivity measurements and the qualitative examination of UV spectra allows the discrimination of non domestic loads and their variability study from one point to another. The identification of critical discharges and organic shock loads has been possible with low investment, and mitigation actions have been proposed. 相似文献
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Occurrence of pharmaceuticals and hormones in drinking water treated from surface waters 总被引:6,自引:0,他引:6
Emmanuelle Vulliet C��cile Cren-Oliv�� Marie-Florence Grenier-Loustalot 《Environmental Chemistry Letters》2011,9(1):103-114
The levels of a wide variety of pharmaceuticals and hormones, in source and potable-water supplies of French drinking water
treatment plants, were assessed. In surface waters, 27 of the 51 target compounds were determined at least once. Paracetamol,
salicylic acid and carbamazepine were quantified in more than 80% of samples. The highest concentration of 71 ng/L was observed
for paracetamol. Twelve other substances were widely found in the surface waters studied, contaminating between 33 and 80%
of the samples. These compounds include analgesics, psychotropic drugs, antibiotics and beta-blockers consistent with the
French consumption, as well as natural hormones (oestrone, progesterone and androgens) and synthetic progestatives. In drinking
water supplies, 25 compounds were also present, salicylic acid being the most frequently detected. Carbamazepine and the β-blocker
atenolol found at lower levels (maximum 2 ng/L), are also present in more than 30% of the contaminated drinking waters. The
pharmaceuticals exhibit different reactivity towards the treatments, while progestagens and androgens seem resistant to most
of them. The effectiveness of the treatments is discussed, as well as the consequences of the presence of all these compounds
on human health. This is the first time that such a long list of compounds (51) is proposed to assessment, and consequently
this study provides the first data on pharmaceuticals and steroids occurrences in French drinking waters and represents a
basis for the assessment of risks for humans. Moreover, at the international level, this is the first time that so many substances
are quantified in drinking water, due to the very low detection limits, especially in the case of the hormones. 相似文献
25.
Nguyen Ngoan Thi Thao Nguyen Luan Minh Nguyen Thuy Thi Thanh Nguyen Thuong Thi Nguyen Duyen Thi Cam Tran Thuan Van 《Environmental Chemistry Letters》2022,20(4):2531-2571
Environmental Chemistry Letters - Because many engineered nanoparticles are toxic, there is a need for methods to fabricate safe nanoparticles such as plant-based nanoparticles. Indeed, plant... 相似文献
26.
The blue mussel, Mytilus edulis, is able to use biochemical cues to sort food particles. Recently, a mucosal lectin (MeML) identified in pallial organs of M. edulis was suggested to play a role in the capture and sorting of food particles. The current study presents data obtained in 2010 showing that sorting efficiencies and MeML gene expression in M. edulis increased when mussels were either fed poor quality food or starved. In addition, results suggest that particle capture and degree of selection increased during the spawning period, although the quality of food delivered to mussels before the experiments seemed to have a stronger impact on particle-sorting efficiency. Overall, the impact of both endogenous (physiological status) and exogenous (food quality) factors were shown to affect the expression of MeML in mussel feeding organs, and the food sorting abilities. 相似文献
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Preference for water quality and its nonmarket valuation can be used to inform the development of pricing policies and long term supply strategies. Tap water quality is a household concern. The objective status quo of water provision varies between households and not between individuals within households, while charges are levied on households not individuals. Individual preferences differ from collective preferences. In households where there are two adults, we examine the preferences of each separately and then as a couple in collective decisions. We show the level of influence each has in developing the collective decision process. We use discrete choice experiments to model preference heterogeneity across three experiments on women, men and on both. We propose a random utility model which decomposes the error structure in the utility of alternatives so as to identify the individual influence in collective decisions. This approach to choice data analysis is new to environmental economics. 相似文献
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Norbert Gonzalez-Flesca André Cicolella Matthew Bates Emmanuelle Bastin 《Environmental science and pollution research international》1999,6(2):95-102
There is a lack of data for health risk assessment of long term personal exposure to certain ubiquitous air pollutants present particularly in urban atmospheres. The relationship between ambient background concentrations and personal exposure is often unknown. A pilot campaign to measure indoor concentrations, outdoor concentrations and personal exposure to benzene, formaldehyde and acetaldehyde was conducted in a medium sized French town. A strong contribution to total personal exposure was observed from indoor sources, especially for formaldehyde and acetaldehyde, suggesting that indoor sources are dominant for these compounds. For benzene, the average personal exposure exceeded a 10 μgm?3 limit value, although this was not the case for the ambient background concentration. For formaldehyde, the limit level was also exceeded. Observations suggest that true personal exposure cannot be determined directly from measurements pertaining from fixed ambient background monitoring stations. It is hoped that this will be taken into consideration by the bodies responsible for monitoring air pollution and the future European Air Quality Directive. 相似文献
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Screening of pharmaceuticals and hormones at the regional scale, in surface and groundwaters intended to human consumption 总被引:6,自引:0,他引:6
As part of a regional screening to evaluate the risk, for the health of populations, to certain classes of emerging substances, several families of pharmaceuticals and hormones were looked for in waters intended to drinking. Thus, 52 substances were investigated in 71 surface waters and 70 groundwaters. Results indicate that no water was free of pollutants, regardless of its origin (surface or groundwater) and the season of collect. The pharmaceuticals most frequently detected and with the highest concentration levels were salicylic acid, carbamazepine and acetaminophen. Among hormones, testosterone, androstenedione and progesterone were detected in almost all the samples. Globally the groundwaters were less contaminated than surface waters in regards pharmaceuticals frequencies and levels. On the other side, androgens and progestagens were present with comparable frequencies and levels in both compartments. The risk linked to the presence of these substances on human health is discussed. 相似文献
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