Partial Decontamination Research Articles

Green remediation and enhanced metal accumulation using moringa oleifera leaf extracts and hydrocarbon-degrading microorganisms in crude oil-impacted soils of the niger delta, nigeria

This emerging technology called “Phytoremediation” which uses plants to remove pollutants from the environment is preferred over traditional methods, because it offers site restoration, partial decontamination, and maintenance of biological activity and physical structure whilst being potentially cheap, visually unobtrusive and with a possibility of bio-recovery of metals. Because of these advantages, phytoremediation is considered as a 'green', sustainable pollution removal process. The present study was designed to evaluate Phytoremediation potential of Moringa oleifera leaf extract on soil contaminated with Spent Engine Oil. Top soil (0-15cm depth) was randomly collected and 5kg each of the composite samples were transferred into fifty (50) plastic buckets with drainage holes at the base, plugged with cotton wool to retain the soil. The Plastic buckets were arranged into five treatment groups with Ten (10) replicates each. The polythene bags were arranged in a completely randomized block design. Spent Engine oil obtained from mechanic shops in Bedwell Calabar, Cross River State, was applied as the pollutant. The Spent engine oil was introduced at different concentration levels (0.3, 0.5, 0.7, and 1.0 l/5kg) into the treatment groups apart from the control (0.0 l/5kg).The results across the various treatment levels where subjected to statistical analysis, using Analysis of variance (ANOVA) and the results showed that physicochemical parameters (soil pH and organic carbon), Heavy Metals present, Total Petroleum Hydrocarbon and Microbial Counts were significantly higher (P<0.05) in treatment groups than the control. The result also showed a significant reduction (P<0.05) of the Total petroleum hydrocarbon after treatment.

Efficacy of water-only or soap and water skin decontamination of chemical warfare agents or simulants using in vitro human models: A systematic review.

Water-only or water and soap are widely recommended as preferred solutions for dermal decontamination. However, limited efficacy data exist. We summarized experimental studies evaluating in vitro efficacy of water-only or soap and water in decontaminating chemical warfare agents (CWA) or their simulants from human skin models. Embase, Covidence®, MEDLINE, PubMed, Web of Science, and Google Scholar were searched for articles using water-only or soap and water decontamination methods for removal of CWA/CWA simulants in in vitro human skin models. Data extraction was completed from seven studies, yielding seven contaminants. Water-only decontamination led to partial decontamination in all skin samples (100%, n = 81/81). Soap and water decontamination led to partial decontamination in all skin samples (100%, n = 143/143). Four studies found decontamination to either paradoxically enhance absorption of contaminants or their penetration rates, known as the "wash-in" effect. Despite recommendations, water-only or water and soap decontamination were found to yield partial decontamination of CWA or their simulants in all human in vitro studies. Thus, more effective decontaminating agents are needed. Some studies demonstrated increased or faster penetration of chemicals following decontamination, which could prove deadly for agents such as VX, although these findings require in vivo validation. Heterogeneity in experimental setups limits interstudy comparison, and it remains unclear when water-only or water and soap are ideal decontaminants, which requires more studies. Pending manuscripts will summarize in vivo human and animal efficacy data. International harmonized efficacy protocol should enable more efficient public health decisions for evidence-based public health decisions.

Efficacy of water skin decontamination in vivo in humans: A systematic review

With the constant possibility of occupational exposures, chemical warfare, and targeted attacks, increased attention has been given to determining effective and timely dermal decontamination strategies. This systematic review summarises experimental studies reporting decontamination with water-based solutions of dermal chemical contaminants with in vivo human data. Embase, MEDLINE, PubMed, Web of Science, and Google Scholar databases were comprehensively searched using search terms ("cutaneous" or "skin" or "dermal" or "percutaneous") and ("decontamination" or "decontaminant" or "skin decontamination") to include 10 studies, representing 18 chemical contaminants, 199 participants, and 351 decontamination outcomes. Three studies included data from decontamination with water (10.8%, n = 38/351 decontamination outcomes), seven with soap and water (68.4%, n = 240/351 decontamination outcomes), and two with 10% isopropanol distilled water (20.8%, n = 73/351 decontamination outcomes). Results of dermal decontamination using water showed complete decontamination (CD) outcomes in 52.6% (n = 20/38) and partial decontamination (PD) in 47.4% (n = 18/38); using soap and water showed PD outcomes in 92.9% (n = 223/240) and minimal to no effect in 7.1% (n = 17/240); and using 10% isopropanol distilled water achieved PD outcomes in 100.0% (n = 73/73). Available data show that decontamination with water, soap and water, and 10% isopropanol distilled water is incomplete. Much remains to be learned about decontamination of the large variety of chemical contaminants including a range of molecular weights, lipid and water solubilities, melting points, volatility, and hydrogen bonds, as well as clinically relevant anatomic sites. A major void exists in data confirming or denying the completeness of decontamination by measuring absorption and excretion. The development of effective decontamination solutions is of high priority.

ПРОВЕДЕНИЕ САНИТАРНОЙ ОБРАБОТКИ НА ЭТАПАХ ОКАЗАНИЯ МЕДИЦИНСКОЙ ПОМОЩИ ПОСТРАДАВШИМ В РАДИАЦИОННОЙ АВАРИИ

Purpose: To summarize and analyze the results of research and practical recommendations on the decontamination of victims in the event of radiation accidents, including taking into account the authors’ experience gained in the initial period of the Chernobyl accident (April – August 1986) and in other local radiation accidents (incidents), as well as during emergency exercises.
 Results: The indications for carrying out decontamination and the technique of its implementation were considered, a comparative assessment of the effectiveness of skin decontamination agents was presented. Recommendations were formulated for determining the priority (urgency) of carrying out decontamination, depending on the level of external radioactive contamination of the victims. Criteria, rules and methods for carrying out decontamination were proposed for use in relation to the practice of medical and hygienic measures at the stages of medical evacuation (accident site, enterprise health center, enterprise sanitary inspection department, triage site, hospital admission department). The features of decontamination of victims with combined radiation injuries and contaminated wounds (burns) were considered, issues of ensuring the radiation safety of medical personnel who provide assistance to victims are touched upon.
 Conclusion: Timely and correctly performed decontamination reduces the exposure of the skin, prevents the entry of radioactive substances into the body and the transfer (spread) of radioactive substances to the subsequent stages of medical evacuation. The main criteria for the urgency (priority) of carrying out decontamination are the levels of radioactive contamination of the skin, contamination nature (radionuclide composition, physicochemical form, etc.) and the presence of victim’s skin lesions (wounds, burns). Decontamination of victims with high levels of radioactive contamination should be considered as a part of the first and subsequent emergency health care and should be carried out as prescribed or with the direct participation of a healthcare professional. At the stages of medical evacuation, decontamination can be carried out if the victim’s condition is stabilized. In the case of a serious condition of the victim, the priority is evacuation to a hospital, while in the prehospital period, as a rule, only partial decontamination of skin areas with high levels of contamination can be carried out. The procedure and rules for decontamination, including the use of skin decontaminating agents, should be reflected in the action plans of the personnel of radiation hazardous enterprises and the plans for medical support of medical units of the FMBA of Russia.

Agrochemical plastic packaging waste decontamination for recycling: Pilot tests in Italy

Agriculture, one of the main economic pillars in Europe, plays a growing important role towards the environmental sustainability of the extra-urban land, in which the agricultural activities may proactively contribute to control and regulate the whole ecological conditions. Modern agriculture currently needs big quantities of agrochemicals, which are necessary for the growth and protection of crops and animals. These agrochemicals are commercially distributed to consumers in many types of containers. The most widely used packaging solutions usually employ plastic materials (e.g., containers for liquid pesticide; sacks for granular fertiliser; etc.). These materials, after the use of the agrochemical, need to be decontaminated, before being entrained in a recycling process, in the framework of a circular economy. In the present paper the main results coming from a EU-funded international project are reported, with specific reference to a pilot station that was realised in Italy with the aim to implement and test a codified system for the decontamination of these plastic containers for agrochemicals. The experimental tests were supported by relevant laboratory analysis, which have confirmed that the triple-rinsing decontamination procedure - traditionally employed by farmers for washing and decontaminating these containers - may be effective only under some well-defined conditions. Triple rinsing by farmers has indeed led to an only partial decontamination of the plastic containers, if farmers did not follow an appropriate triple-rinsing protocol, or did not triple-rinse the containers immediately after their emptying.

Тканиноспецифічність впливу фізичних та фармакологічних чинників на антиоксидантний захист у тварин з ерозивно-виразковою патологією гастродуоденальної зони

<p><span lang="EN">Influence of the natural magnetic field (MP) is an integral part of the existence of all living systems on Earth. Artificial MPS appeared precisely due to human activity. It is established that the interaction of MP with biosystems, its biological activity depends on the biotropic parameters of this field, such as frequency, intensity, gradient (rate of growth), vector, pulse shape, exposure time and localization of influence. </span><span lang="EN">There is now no single point of view regarding the mechanisms of interaction of the MP with biological objects. Experimental investigations have documented the influence of MP on the reactions occurring in the free radical type. Free radical pathologies include diseases such as gastroesophageal reflux disease and peptic ulcer disease. Therefore, the search for factors that can affect the components of the system of oxidative homeostasis remains. </span><span lang="EN">The purpose of the work is to evaluate the isolated effect of the magnetic field and in combination with injections of L-arginine-L-glutamate into lipoperoxidation processes and antioxidant defense system in rat tissues with experimental pathology of the gastroduodenal zone. The modeling of erosive-ulcerative lesions of the gastroduodenal zone in rats was accompanied by an imbalance in the functioning of antioxidant defense systems and the intensification of lipoeroxidation LPO processes in the blood, liver, brain and stomach tissues of experimental animals. Applications of a magnetic field to animals with simulated pathology of the gastroduodenal zone resulted in inhibition of the processes of LPO in the blood of experimental rats at the activation of free radical reactions in the liver, brain and stomach tissues, on the background of partial decontamination of the glutathione system enzymes against the backdrop of an increase in the amount of reduced glutathione. With the combined action of glutargin and magnetic field in the blood, liver and brain tissues of experimental rats with erosive-ulcerative defeat of the gastroduodenal zone, activation of anti-radical, anti-peroxide protection enzymes, increased levels of reduced glutathione against the inhibition of glutathione reductase activity and a decrease in the intensity of the LPO processes with simultaneous normalization </span><span lang="EN-US">of </span><span lang="EN">processes of lipoperoxidation in the stomach tissue took place.</span></p>

Electro-Fenton and Photoelectro-Fenton Degradation of Sulfanilic Acid Using a Boron-Doped Diamond Anode and an Air Diffusion Cathode

The mineralization of sulfanilic acid has been studied by electro-Fenton (EF) and photoelectro-Fenton (PEF) reaction with UVA light using an undivided electrochemical cell with a boron-doped diamond (BDD) anode and an air diffusion cathode able to generate H(2)O(2). Organics were then oxidized by hydroxyl radicals formed at the anode surface from water oxidation and in the bulk from Fenton's reaction between generated H(2)O(2) and added Fe(2+). The UVA irradiation in PEF enhanced the production of hydroxyl radicals in the bulk, accelerating the removal of organics and photodecomposed intermediates like Fe(III)-carboxylate complexes. Partial decontamination of 1.39 mM sulfanilic acid solutions was achieved by EF until 100 mA cm(-2) at optimum conditions of 0.4 mM Fe(2+) and pH 3.0. The increase in current density and substrate content led to an almost total mineralization. In contrast, the PEF process was more powerful, yielding almost complete mineralization in less electrolysis time under comparable conditions. The kinetics for sulfanilic acid decay always followed a pseudo-first-order reaction. Hydroquinone and p-benzoquinone were detected as aromatic intermediates, whereas acetic, maleic, formic, oxalic, and oxamic acids were identified as generated carboxylic acids. NH(4)(+) ion was preferentially released in both treatments, along with NO(3)(-) ion in smaller proportion.

Removal of metals by sorghum plants from contaminated land

The growth of high biomass crops facilitated by optimal of agronomic practices has been considered as an alternative to phytoremediation of soils contaminated by heavy metals. A field trial was carried out to evaluate the phytoextraction efficiency of heavy metals by three varieties of sweet sorghum (Sorghum biocolor L.), a high biomass energy plant. Ethylene diamine tetraacetate (EDTA), ammonium nitrate (NH4NO3) and ammonium sulphate ((NH4)2SO4) were tested for their abilities to enhance the removal of heavy metals Pb, Cd, Zn, and Cu by sweet sorghum from a contaminated agricultural soil. Sorghum plants always achieved the greatest removal of Pb by leaves and the greatest removal of Cd, Zn and Cu by stems. There was no significant difference among the Keller, Rio and Mray varieties of sweet sorghums in accumulating heavy metals. EDTA treatment was more efficient than ammonium nitrate and ammonium sulphate in promoting Pb accumulation in sweet sorghum from the contaminated agricultural soil. The application of ammonium nitrate and ammonium sulphate increased the accumulation of both Zn and Cd in roots of sorghum plants. Results from this study suggest that cropping of sorghum plants facilitated by agronomic practices may be a sustainable technique for partial decontamination of heavy metal contaminated soils.

Bioremediation of polychlorinated biphenyl-contaminated soil using carvone and surfactant-grown bacteria.

Partial bioremediation of polychlorinated biphenyl (PCB)-contaminated soil was achieved by repeated applications of PCB-degrading bacteria and a surfactant applied 34 times over an 18-week period. Two bacterial species, Arthrobacter sp. strain B1B and Ralstonia eutrophus H850, were induced for PCB degradation by carvone and salicylic acid, respectively, and were complementary for the removal of different PCB congeners. A variety of application strategies was examined utilizing a surfactant, sorbitan trioleate, which served both as a carbon substrate for the inoculum and as a detergent for the mobilization of PCBs. In soil containing 100 microg Aroclor 1242 g(-1) soil, bioaugmentation resulted in 55-59% PCB removal after 34 applications. However, most PCB removal occurred within the first 9 weeks. In contrast, repeated addition of surfactant and carvone to non-inoculated soil resulted in 30-36% PCB removal by the indigenous soil bacteria. The results suggest that bioaugmentation with surfactant-grown, carvone-induced, PCB-degrading bacteria may provide an effective treatment for partial decontamination of PCB-contaminated soils.

Partial decontamination of rotifers with ultraviolet radiation: the effect of changes in the bacterial load and flora of rotifers on mortalities in start-feeding larval turbot

Exposure of the rotifer Brachionus plicatilis to ultraviolet radiation in 1 mm deep liquid layers at an energy intensity of 38 mW cm −2 reduced the rotifer bacterial load by >90% within 2 min. Such radiation doses had no significant effect upon rotifer viability, fatty acid composition, swimming or feeding activity. The surviving bacterial flora of irradiated rotifers was similar to that of un-irradiated rotifers and there was no evidence of major differences in sensitivity to ultraviolet radiation between different bacteria. For irradiation of large numbers of rotifers, a flow-through cell was used, operated with rotifer densities of 200 ml −1 and a flow rate of 1.5 l min −1. In two separate field trials involving groups of 34,000 turbot larvae per group, higher survival was found in groups receiving ultraviolet-irradiated rotifers in which the bacterial load was reduced by 88%. This was attributed to the slower rate of colonisation of the larval gut by bacteria, as a consequence of the lower bacterial load on the rotifers. Attempts to introduce specified bacteria into the larval turbot gut in significant numbers by colonisation of either normal or irradiated rotifers with particular bacteria were unsuccessful.

Fumonisin-contaminated maize: physical treatment for the partial decontamination of bulk shipments.

Ten maize samples, randomly selected from a bulk shipment imported into South Africa, were characterized by a wide distribution in particulate size. Following fractionation by sieving through a 3 mm screen, the 'kernels' (fractions > or = 3 mm) corresponding to between 80.0 and 95.3% of the samples by mass, were contaminated with total fumonisin levels of between 530 and 1890 ng/g. Conversely, those fractions termed 'fines' (< 3 mm) had significantly higher total fumonisin concentrations of between 12,340 and 27,460 ng/g, and accounted for between 4.7 and 20.0% of the samples by mass. The data indicated that removal of the 'fines' resulted in overall reductions in total fumonisin levels of between 26.2 and 69.4%. It is suggested that initial removal of 'fines' from bulk shipments of maize, prior to further processing, could be considered as a preliminary fumonisin-decontamination procedure.

Magnetic extraction of radioactive contaminations from Chernobyl NPP regions

Preliminary experimental data on decontamination of the soil of a 30-km-zone around the Chernobyl nuclear power plant from radioactive contaminants by dry magnetic separation are presented. The facility used for performing the experiments is briefly described. The first run of experiments confirmed the feasibility of partial decontamination of various types of soils. The second run of experiments helped to clarify the effect of preheating (up to 500 degrees C) and repeated decontamination of the soil samples on the degree of soil decontamination. As expected, the samples of initial activity of 100 Bq/g were decontaminated basically to permissible concentrations. An enhanced degree of /sup 144/Ce and /sup 106/Ru decontamination seems to be associated with the fact that readily extractable fuel elements possess higher susceptibility than cesium. >

Resistance to sulfur poisoning of metal catalysts: Dehydrogenation of cyclohexane on [formula omitted] catalysts

Model Pt catalysts, containing ~0.6 wt% Pt, were prepared by deposition of dinitrodiamino-platinum salt on a nonmicroporous alumina. The carrier has been modified by addition of K or Cl. The dispersion of the metallic phase was varied through different decomposition-reduction processes, but the final activation conditions were identical in all cases. The various catalysts have been tested in the dehydrogenation of cyclohexane which was confirmed to be a structure-insensitive reaction. The thiotolerance level of the various catalysts was measured with a feed contaminated with 0.6 ppm of thiophene. The thiotolerance level is more affected by the acidity of the support (presence of K or Cl) than by variations of Pt particle size. This has been confirmed by making sudden injections of CH 2Cl 2 or (C 2H 5) 3N into the feed. On removing thiophene from the reactant mixture partial decontamination occurred and the activity recovered to ~50% of the initial value.