134 research outputs found

    The astonishing 63Ni radioactivity reduction in radioactive wastes by means of ultrasounds application

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    Nowadays, the radioactive wastes production is certainly one of the main issues along with their storage. The most interesting way to treat them would certainly be the radioactivity reduction. In this paper we show that the 63Ni radioactivity reduction by ultrasounds is not a violation of the exponential decay law but can be explained by the Deformed Space–Time theory. The cavitation procedure under the DST conditions achieves a radioactivity decrease around 14% in 200 s. Comparing these results with the theoretical ones obtained by the decay law, we earn more than 20 years in the 63Ni radioactivity decrease. For confirming the data, ICP-MS measurements were performed on cavitated and no-cavitated samples: once again, the 14%-difference (with CV 5%) was obtained from the analyses of both samples. Even if the data are not definitive, the new idea is that a radioactive substance can be "normalized" by its transformation into a normal stable one without radiation emission overcoming the traditional approaches (dilution, inertization, radioactive transmutation with fast neutron irradiation) and avoiding the use of large deposits or big reactors. Our results may be considered as starting point to pave the way to new methods to treat useless harmful radioactive substances from nuclear or medicine industry

    Impact of electronic alternatives to tobacco cigarettes on indoor air particular matter levels

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    An aerosol study was carried out in a test room measuring particulate matter (PM) with an aerodynamic diameter smaller than 10, 4, 2.5 and 1 m (PM10, PM4, PM2.5, PM1) before and during the use of electronic alternatives to tobacco cigarettes (EATC) IQOS®, GLO®, JUUL®, with dierent kinds of sticks/pods, as well as during the smoking of a conventional tobacco cigarette. The aerosol was mainly in the PM1 size range (>95%). All studied EATCs caused lower indoor PM1 concentrations than conventional tobacco cigarettes. Nevertheless, they determined a worsening of indoor-PM1 concentration that ranged from very mild for JUUL®—depending on the pod used—to considerably severe for IQOS® and GLO®. Median values ranged from 11.00 (Iqos3 and Juul2) to 337.5 g m3 (Iqos4). The high variability of particle loadings was attributed both to the type of stick/pod used and to the dierent way of smoking of volunteers who smoked/vaped during the experiments. Moreover, during vaping IQOS® and GLO® indoor PM1 concentrations reach levels by far higher than outdoor concentrations that range from 14 to 21 g m3, especially during the exhalation of the smoke. From these results emerge an urgent need of a legislative regulation limiting the use of such devices in public places

    regional deposition of submicrometer aerosol in the human respiratory system determined at 1 s time resolution of particle size distribution measurements

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    Submicrometer aerosol size number distributions have been measured in downtown Rome with 1 s time resolution. From these data, the particle deposition in the human respiratory system has been assessed for infants, children and adults under different exercise levels. The estimates are reported as size segregated percentages and as total particle numbers deposited. The greatest percentages of particles are deposited in the alveolar interstitial region. Deposited doses, expressed per unit body weight or per unit alveolar surface area, indicate that children and infants are more at risk than adults. Following vehicle exhausts, nucleation particle concentrations increase within a few seconds and decrease in the time scale of tens of seconds. In accordance with traffic cycles, such particles are very common during the day, and decrease at night, when accumulation mode particles are more prevalent. As a consequence, the exposure scenario, in proximity to traffic, may be represented by a sequence of short-term peak exposures. The appraisal of such brief exposures depends on the time resolution of measurements, being underestimated if aerosol measurements are performed with resolutions on the time scale of minutes. The health relevance of such exposure patterns needs to be investigated, and the relevant measurement averaging time should also be defined

    A Review of the Analytical Methods Based on Chromatography for Analyzing Glyphosate in Foods

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    Glyphosate is a pesticide widely used in agriculture, horticulture, and silviculture as well as around homes and gardens. It was introduced by Monsanto in the early 1970s, and it is a broad spectrum, nonselective, post-emergence herbicide that inhibits plants’ shikimic acid pathway. Glyphosate is considered as “difficult herbicide” in terms of trace analysis. It has low molecular weight, low volatility, thermal lability, and good water solubility. These properties cause problems in its extraction, purification, and detection. The determination often requires additional processes that may allow quantification by chromatographic methods. Several analytical procedures have been developed based on solid-phase extraction, ion-exchange chromatography, or matrix solid phase dispersion. Most published methods involve liquid extraction followed by clean-up. This review would like to revise the literature on this issue discussing the relevant chromatographic methods reported in the literature in terms of analytical parameters for analyzing such compound in food chain

    investigation on the behavior of pesticides in atmosphere

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    Although pesticides are widely used in agriculture, they and in particular the relative residues in foodstuffs, water and atmosphere, may cause remarkable sanitary problems due to the harmful effects (carcinogenic and mutagenic effects) on the human health. In fact, their spread in waters and atmosphere can produce undesired effects on various organisms and/or water contamination.This paper shows an analytical approach based on XAD-2 adsorbent and GC analysis for evaluating the pesticide trend in atmosphere: in particular, the pesticides investigated are omethoate, dicrotofos, disulfoton, dimethoate, parathion methyl, formothion, paraoxon ethyl, malaoxon, parathion ethyl, iodofenfos and triazofos. For the analytical methodology a linearity response was obtained (r^2 = 0.9988) in GC-NPD whereas the limits of detection range between 2 and 5 pg/ÎĽL in GC-NPD with a Relative Standard Deviation below 9.5. Finally, this approach has been successfully applied to real samples: the results show that dimethoate concentration decreases with increasing distance from the sampling site but it is still persistent in atmosphere after few days from the pesticide spraying

    Size resolved aerosol respiratory doses in a Mediterranean urban area: From PM10 to ultrafine particles

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    In the framework of the 2017 "carbonaceous aerosol in Rome and Environs" (CARE) experiment, particle number size distributions have been continuously measured on February 2017 in downtown Rome. These data have been used to estimate, through MPPD model, size and time resolved particle mass, surface area and number doses deposited into the respiratory system. Dosimetry estimates are presented for PM10, PM2.5, PM1 and Ultrafine Particles (UFPs), in relation to the aerosol sources peculiar to the Mediterranean basin and to the atmospheric conditions. Particular emphasis is focused on UFPs and their fraction deposited on the olfactory bulb, in view of their possible translocation to the brain. The site of PM10 deposition within the respiratory system considerably changes, depending on the aerosol sources and then on its different size distributions. On making associations between health endpoints and aerosol mass concentrations, the relevant coarse and fine fractions would be more properly adopted, because they have different sources, different capability of penetrating deep into the respiratory system and different toxicological implications. The separation between them should be set at 1ʵm, rather than at 2.5ʵm, because the fine fraction is considerably less affected by the contribution of the natural sources. Mass dose is a suitable metric to describe coarse aerosol events but gives a poor representation of combustion aerosol. This fraction of particles, made of UFPs and of accumulation mode particles (mainly with size below 0.2ʵm), is of high health relevance. It elicited the highest oxidative activity in the CARE experiment and is properly described by the particle surface area and by the number metrics. Such metrics are even more relevant for the UFP doses deposited on the olfactory bulb, in consideration of the role recognized to oxidative stress in the progression of neurodegenerative diseases. Such metrics would be more appropriate, rather than PMx mass concentrations, to correlate neurodegenerative pathologies with aerosol pollution

    Dataset of pahs determined in home-made honey samples collected in central Italy by means of dllme-gc-ms and cluster analysis for studying the source apportionment

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    This paper would like to show all the data related to an intensive field campaign focused on the characterization of the Polyaromatic Hydrocarbons (PAHs) composition profile in almost 60 honey samples collected in Central Italy. The analytical data here reported are the base for a study aimed to identify the pollution sources in a region. 22 PAHs were analyzed by means of ultrasound-vortex-assisted dispersive liquid-liquid micro-extraction (DLLME) procedure followed by a triple quadrupole gas chromatograph/mass spectrometer (GC-MS). A chemometrics approach has been carried out for evaluating all the data: in particular, principal component analysis and cluster analysis has been used both for the identification of the main natural/anthropogenic pollutants affecting a site and for evaluating the air quality

    Ultrafine particles and PM2.5 in the air of cities around the world : Are they representative of each other?

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    Can mitigating only particle mass, as the existing air quality measures do, ultimately lead to reduction in ultrafine particles (UFP)? The aim of this study was to provide a broader urban perspective on the relationship between UFP, measured in terms of particle number concentration (PNC) and PM2.5 (mass concentration of particles with aerodynamic diameter 1 for roadside sites and <1 for urban background sites with lower values for more polluted cities. The Pearson's r ranged from 0.09 to 0.64 for the log-transformed data, indicating generally poor linear correlation between PNC and PM2.5. Therefore, PNC and PM2.5 measurements are not representative of each other; and regulating PM2.5 does little to reduce PNC. This highlights the need to establish regulatory approaches and control measures to address the impacts of elevated UFP concentrations, especially in urban areas, considering their potential health risks.Peer reviewe
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