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The soil of a coastal Mexican refinery is quite contaminated, especially by hydrocarbons, with detected concentrations up to 130000 mg kg(-1) as TPHs (total petroleum hydrocarbons). The main sources of contamination are pipelines, valves, and old storage tanks, besides the land disposal of untreated hydrocarbon sediments derived from the cleaning of storage tanks. A health risk assessment (HRA) was carried out in order to measure the risk hazard indexes and clean-up standards for the refinery soil. HRA suggested the following actions to be taken: benzene concentrations must be reduced in eight of the 16 studied refinery zones to 0.0074-0.0078 mg kg(-1). Also, vanadium concentration must be reduced in two zones up to a concentration of 100 mg kg(-1). In only one of all of the studied zones, benzo(a)pyrene concentration must be reduced to 0.1 mg kg(-1). After 1 yr, TPHs showed a diminution of about 52%. Even though TPHs concentrations were variable, during 1999 the average concentrations were as much as 15.5 times the goal concentration. For year 2000, TPHs concentrations were only 7.4-fold the proposed value. For the 1999-2000 period, PAHs (polycyclic aromatic hydrocarbons) concentrations decreased by 82%. Some PAHs with 2, 3, 4, and 5 aromatic rings were removed up to 100% values.  相似文献   
3.
Trisomy 12 mosaicism diagnosed at 16 weeks' amniocentesis in a 42-year-old woman was not confirmed at 18 weeks' gestational age in amniotic fluid or fetal blood. Fetal skin biopsy performed at the same time did, however, allow the detection of trisomy 12 in 1 of 14 fibroblasts analysed. Fetal skin biopsy can be included within the diagnostic procedures to be performed when a level III mosaicism is found in the amniotic fluid.  相似文献   
4.
Synthesis of poly(hydroxyalkanoate) from hydrolyzed linseed oil   总被引:3,自引:0,他引:3  
Pseudomonas putida was grown on a mixture of long-chain fatty acids obtained by hydrolysis of linseed oil. A poly(3-hydroxyalkanoate) containing 51.2% of unsaturated monomers was obtained. A considerable percentage (13.6%) was constituted by C14 and C16 monomers containing three double-bonds in the side chains. The polymer showed a high tendency to crosslink when it was kept in presence of air. In the crosslinked polymer no polyunsaturated monomers could be detected.  相似文献   
5.
Several population studies relate exposure to high levels of arsenic with an increased incidence of ischemic heart disease and cardiovascular mortality. An association has been shown between exposure to high levels of arsenic and cardiovascular risk factors such as hypertension and diabetes mellitus, and vascular damage such as subclinical carotid atherosclerosis. The mechanisms underlying these phenomena are currently being studied and appear to indicate an alteration of vascular function. However, the effects of low levels of exposure to arsenic and their potential detrimental cardiovascular effect are less explored. The article provides an overview of the pathophysiologic mechanisms linking low-level arsenic exposure to the occurrence of cardiovascular disease and its complications, and some potential preventive strategies to implement.  相似文献   
6.
Environmental Science and Pollution Research - The poor adsorption capacity of sandy soils is one of the primary reasons of a high level of phosphorus (P) leaching. Silicon (Si)-rich soil...  相似文献   
7.
Effective selective collection (SC) has been increasing in many countries of the European Union. As a consequence the composition of residual municipal solid waste (RMSW) is changing not only because of economic development, but also due to the collection system. The input of RMSW treatment plants is thus not homogeneous. This paper analyses two case studies involving a total of five SC scenarios and their impact on the generation of solid recovered fuel (SRF) with/without bio-drying, post-treatment and packaging take back programs (TBPs). These case studies are based on two types of SC: kerbside and drop-off. The latest regulation on SRF classification is taken into account: energy content, Cl and Hg concentrations are assessed and discussed. The role of the respirometric index (RI) is also analyzed. Results show that when SC is highly efficient RMSW can be classified directly as SRF, but only if the introduction of RI does not set stringent respirometric targets. The role of packaging TBPs is important as the residual waste remaining after the packaging has been processed, can be valorized increasing the lower heating value (LHV) of the residual RMSW and minimizing the streams that should be landfilled. The source separation of food waste has a significant impact on the suitability of bio-drying: when the SC of food waste is very efficient, its percentage in the RMSW may be too low for effective bio-drying.  相似文献   
8.
Parabens are used because of their antimicrobial effects, yet they have multiple adverse effects. The aim of this work was to evaluate the bactericidal activity and bacterial toxicity of the most common parabens: methylparaben, ethylparaben, propylparaben, isopropylparaben, butylparaben, isobutylparaben and phenylparaben. The bactericidal action was evaluated by means of the dilution-neutralization method against Escherichia coli and Staphylococcus aureus, and the biotest of inhibition of growth of E. coli was applied for the bacterial toxicity assay. Bactericidal concentrations were reached only for propylparaben, butylparaben and isobutylparaben. The toxicity study showed methylparaben to be the least toxic, whereas the most toxic one was phenylparaben. It can be concluded that the disinfectant activity of the parabens studied is insignificant against S. aureus and E. coli. Acute toxicity is very low, and the inhibitory effect is weak. Our results provide information about the risk–benefit balance of parabens use.  相似文献   
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Abstract

The presence of diethyl-phthalate (DEP), dibutyl-phthalate (DBP), butylbenzyl-phthalate (BBP), diethylhexyl-phthalate (DEHP) and diisononyl-phthalate (DINP) was determined in 295 tequila samples. They were grouped by age of maturation (white, aged, extra aged or ultra aged) and year of production (between 2013 and 2018). Gas Chromatography coupled with Mass Spectrometry was used for identification and quantification. The results showed that 65 samples (22% of the total) were phthalate free. DEP (0.13-0.27?mg/kg), BBP (0.05–2.91?mg/kg) and DINP (1.64–3.43?mg/kg) were detected in 11 (3.73%), 37 (12.54%) and 5 (1.69%) samples, respectively. But, these concentrations did not exceed the maximum permitted limits (MPL) of phthalates for alcoholic beverages. DBP (0.01–2.20?mg/kg) and DEHP (0.03–4.64?mg/kg) were detected in 96 (32.54%) and 224 (75.93%) samples, from them only 10 (3.39%) and 15 (5.08%) samples, respectively, exceeded the MPL for alcoholic beverages and they were few tequilas produced in the year 2014 or before. DEHP was the most frequent phthalate found in tequila and observed DEHP concentrations were 2-times higher in ultra aged tequilas compared to those in white tequilas. We concluded that all tequilas produced in 2015 and after, satisfied the international standards for these compounds.  相似文献   
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