59 research outputs found

    Bio-induced reduction of Cr(VI) in aquifers by organic substrates injection

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    Hexavalent chromium is a primary toxic element used in galvanic processes, in metallurgical industry and for the production of dyes and pigments. Conventional methods for Cr(VI) remediation, pump&treat and excavation, are expensive and require a large amount of energy and time. Innovative technologies include bio-induced reduction, that is Cr(VI) reduction to Cr(III) by injection of organic substrates that are readily biodegraded by autochthonous microorganisms in the aquifer, resulting in reducing conditions. Lab scale batch tests were carried out, with two different soil (A and B) and solid/liquid ratios (25% and 50% on weight basis). Initial Cr(VI) concentrations were 5000 or 10000 µg/L. Ultrafiltration permeates of cheese whey and beer distillation residues were used as the organic substrates. In all microcosms, dissolved oxygen decreased from about 6 mg/L to values <1 mg/L after 1-2 d incubation, and the redox potential from approximately +250 mV to -400 mV by 11 d. After about 40 days, the highest Cr(VI) abatements were obtained in soil A microcosms fed with beer distillation residues, as soil A had an initial total heterotrophic bacteria concentration three orders of magnitude higher than soil B. Fe(II) availability was also a key factor in Cr(III) co-precipitation

    Bioremediation of Hexavalent Chromium—A Few Significant Site Histories in Italy

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    In Lombardy (Italy), about 25% of the sites ranked in the Regional Plan of Contaminated Sites are affected by Cr(VI) in groundwater and/or soil. Therefore innovative sustainable remediation techniques are under investigation, with pilot- or full-scale applications. In situ bioremediation has a significant role in the remediation techniques for its general sustainability in terms of environmental impact and costs. However, while organics can be mineralized, inorganics can only change their oxidation state, hopefully reducing their toxicity and mobility in the environment. Various patented products were used at five polluted sites in order to reduce Cr(VI) to Cr(III) via bio-induced reduction, bio-reduction and bioimmobilization. The experience pointed out that Cr(VI) concentration in groundwater can be significantly reduced (up to three order of magnitudes), but the unsaturated zone should be treated as well in order to solve the problem definitely. Soil heterogeneity is a critical issue and mixtures usually have to be injected at different depths. Iron, manganese and sulphate side-contamination can result in groundwater after injections

    An integrated human health risk assessment framework for alkylphenols due to drinking water and edible crop consumption

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    INTRODUCTION The scarcity of clean freshwater is becoming a major issue for present and future generations, especially in densely urbanised areas. This situation promotes the potential cross-contamination of different environmental compartments by contaminants of emerging concern (CECs) which, in fact, have already been detected worldwide in surface water, groundwater and soils. In particular, the CECs released by wastewater treatment plants (WWTPs) can end up both in the recipient surface water and groundwater, both of which are used as drinking water (DW) sources. Furthermore, if those water sources and reclaimed wastewater are used for irrigation, CECs can be directly absorbed by crops intended for human consumption or accumulate in soil and translocate to crops over time. Hence, both DW and edible crops are critical CEC exposure pathways for humans, the combined effect of which requires further investigation. This work is aimed at developing an integrated framework for a quantitative chemical risk assessment due to CECs in complex multiple-use scenarios, combining DW and edible crop consumption, as a decision-making support tool for optimising solutions to minimise risks and social costs. METHODOLOGY The developed procedure includes several steps. Firstly, the analysed system boundaries are defined, to evaluate all the phenomena affecting the fate of CECs from source to end user. Then, CEC migration (e.g. diffusion in surface water, infiltration in soil, uptake by food crops) and human exposure (via water and edible crop consumption) are modelled in an integrated framework as a function of boundary conditions, CECs and by-products characteristics, and proposed interventions. Exposure models are calibrated through literature data, field monitoring and lab tests where, for instance, the CECs’ fate and uptake by vegetables from contaminated soils have been investigated. In the hazard assessment step, a toxicological characterisation was performed to obtain single CEC adverse effect potencies, aimed at applying the Relative Potency Factors methodology for combining CECs that affect the same endpoint. Lastly, exposure and hazard assessment steps are combined to quantitatively estimate the risk to human health from a mixture of CECs, which includes uncertainty analyses to account for knowledge gaps and to provide decision-makers with the confidence level of the risk estimation. RESULTS The developed quantitative risk assessment procedure has been applied to a case study on the mixture of two alkylphenols, i.e. bisphenol-A (BPA) and nonylphenol (NP), used as reference CECs. Literature and field-monitoring data were used to feed the model, with an estimate of BPA and NP concentration in DW up to 0.1 and 0.35 μg/L, respectively, as a function of different system boundary conditions. As for their uptake in edible crops, lab tests with contaminated soil (BPA=75 μg/kg and NP=10 mg/kg, according to the range reported in literature for soil irrigated with reclaimed wastewater or amended with biosolids) demonstrated a significant transfer of NP from soil to vegetables, with concentrations of up to 230 μg/kg fresh weight (f.w.) in the edible parts. No BPA (&lt;8 μg/kg f.w.) was found in vegetables, unlike its metabolite para-hydroxybenzoic acid (up to 56 μg/kg f.w). Those results highlight that both DW and edible crop consumption exposure pathways are critical for the risk to human health due to BPA, NP and their by-products. Several interventions in WWTPs or in DW treatment plants and distribution networks were simulated, demonstrating promising cumulative risk reduction. DISCUSSION Integrated modelling of the fate of CEC mixtures in complex multiple-use water systems, combined with quantitative risk assessment, has proven to be an effective tool to identify the main causes of risk for humans and to assign the various CEC source contributions. Lab tests proved to be useful to investigate the fate of CECs, including metabolites, in the soil system and potential transfer to food crops, corroborating the information from literature and monitoring data for model calibration. Integrated modelling also made it possible to explore several intervention strategies to be adopted at different points of the water system, identifying those that achieve the minimum overall mixture risk. Moreover, in addition to CEC toxicological characterisation, this procedure allows decision-makers to prioritise CECs to be regulated not only based on their exposure levels but looking at their contribution to the overall mixture risk. Lastly, uncertainty analysis made it possible to properly consider the availability and quality of CEC data, especially as regards their physical-chemical behaviour and toxicity, thereby providing the degree of confidence for the estimated risk, which is a key factor for taking informed decisions concerning CEC

    Five-Year Vapor Monitoring for Risk Management at a Hydrocarbon-Polluted Site

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    Soil remediation (excavation and off site disposal) was partially carried out in 2005 at a site in Milan (Italy), leaving a residual volume of soil polluted with petroleum-derived hydrocarbons. Indoor air, outdoor air, crawl-space air and soil gas samplings have been carried out since January 2009. In March 2011 the monitoring network was upgraded to its final configuration (18 indoor, 7 outdoor and 4 crawl-space sampling locations, 60 soil gas probes at four different depths from ground surface); after that, one monitoring campaign a season was performed till November 2013, fractionating hydrocarbons according to a modified version of the Massachusetts Department of Environmental Protection approach. In order to permanently keep risk below acceptable levels, a mitigation system of the contaminated source was installed in December 2013 and it is still working. Three monitoring campaigns of ambient air have been performed since then. Although not strictly necessary in terms of time-averaged health risk, the mitigation system allowed to extract significant amounts of mono- and light poly-cyclic aromatic hydrocarbons. This has helped manage worries about future uncontrolled exposure of people working at the site

    In Situ Aerobic Biostimulation of Groundwater at a National Priority Site in Italy

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    Sarroch plant (CA, Italy) is an industrial area listed in the Italian Priority List of polluted sites. Pollution in groundwater has been addressed thanks to the design of a remediation action based on the aerobic biodegradation of petroleum hydrocarbons (predominantly mono-aromatic and short-chain aliphatic hydrocarbons) promoted by the injection of oxygen-releasing compounds. The feasibility of biostimulation at the site was preliminary assessed by means of laboratory tests. The direct push injection of the product has been foreseen at 2800 points, distributed along multiple lines perpendicular to the groundwater flow direction, over a total length of approximately 8 km and a total area of 90 hectares. According to the pollutant concentration measured in the different zones of the site, a different number of injection campaigns and injection frequency has been scheduled (3 to 10 campaigns, every 5 to 12 months). The estimated cost for the bioremediation action is 23 million Euros. Compared to the previous project approved in 2010, including a seafront physical barrier and groundwater circulation wells – in situ well stripping, the in situ injection of the oxygen-releasing compounds is an improvement toward a quicker, more effective and sustainable remediation of groundwater at the site. In view of all this, in 2017 the public authorities approved the variant of the project

    A public early intervention approach to first-episode psychosis: treated incidence over 7 years in the Emilia-Romagna region.

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    Aim: To estimate the treated incidence of individuals with first-episode psychosis (FEP) who contacted the Emilia-Romagna public mental healthcare system (Italy); to examine the variability of incidence and user characteristics across centres and years. Methods: We computed the raw treated incidence in 2013–2019, based on FEP users aged 18–35, seen within or outside the regional program for FEP. We modelled FEP incidence across 10 catchment areas and 7 years using Bayesian Poisson and Negative Binomial Generalized Linear Models of varying complexity. We explored associations between user characteristics, study centre and year comparing variables and socioclinical clusters of subjects. Results: Thousand three hundred and eighteen individuals were treated for FEP (raw incidence: 25.3 / 100.000 inhabitant year, IQR: 15.3). A Negative Binomial location-scale model with area, population density and year as predictors found that incidence and its variability changed across centres (Bologna: 36.55; 95% CrI: 30.39–43.86; Imola: 3.07; 95% CrI: 1.61–4.99) but did not follow linear temporal trends or density. Centers were associated with different user age, gender, migrant status, occupation, living conditions and cluster distribution. Year was associated negatively with HoNOS score (R = 0.09, p &lt; .001), duration of untreated psychosis (R = 0.12, p &lt; .001) and referral type. Conclusions: The Emilia-Romagna region presents a relatively high but variable incidence of FEP across areas, but not in time. More granular information on social, ethnic and cultural factors may increase the level of explanation and prediction of FEP incidence and characteristics, shedding light on social and healthcare factors influencing FEP

    Sistema Integrato Multicentrico di Indicatori. Rapporto 2005. Provincia di Parma.

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    The SIMI (Integrated System of Indicators multicenter) Project contributes to the development of an integrated management of informative data streams related to drug addicted persons. This report analyzes the phenomenon of addiction on the territory of the Parma Province through a description of the network services that provide care and rehabilitation of those addicted. Besides the characteristics of users of local services for addictions, has been developed the analysis of the subjects reported to the prefectures for use of illegal drugs and any action taken. Standard methods of estimation were also applied to quantify the proportion of users of substances that do not relate to services and to identify certain characteristics.Il Progetto SIMI (Sistema Integrato Multicentrico di Indicatori) intende contribuire allo sviluppo di una gestione integrata e sinergica dei flussi informativi relativi ai consumatori di sostanze stupefacenti afferenti alle diverse amministrazioni dello Stato. In linea con quanto proposto dall\u27Osservatorio europeo di Lisbona, per la descrizione e analisi del fenomeno connesso all\u27uso/abuso di sostanze, risulta di fondamentale importanza la possibilit? di ottenere informazioni esaustive e comparabili sulle persone che usano e/o abusano di sostanze psicotrope. Il presente rapporto analizza il fenomeno delle dipendenze sul territorio della provincia di Parma attraverso la descrizione della rete dei servizi preposti alla cura e riabilitazione dei soggetti tossicodipendenti. Accanto alle caratteristiche degli utenti dei servizi territoriali per le dipendenze, ? stata sviluppata l\u27analisi dei soggetti segnalati alle Prefetture per uso di sostanze illegali e degli eventuali provvedimenti adottati. Sono state inoltre applicate metodologie standard di stima per quantificare la quota parte di utilizzatori di sostanze che non afferiscono ai servizi e per identificarne alcune caratteristiche

    Rapporto 2007. Quadro degli interventi di prevenzione, cura e riabilitazione sul consumo di droghe nella provincia di Rimini.

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    Report on the state of legal and illegal substances use in the territory of Rimini province.La relazione ? articolata in 3 parti. Nella prima - diffusione delle sostanze - vengono riportati gli ultimi dati relativi alla stima dei consumatori di sostanze psicotrope nella provincia di Rimini attraverso la sintesi di due indagini sulla popolazione generale (indagine Ipsad?) e sulla popolazione studentesca di et? 15-19 anni (indagine Espad-Italia?). Una seconda parte - attivit? dei servizi - in cui vengo descritte non solo le caratteristiche delle persone che accedono ai servizi per le dipendenze pubblici e privati, compresa il Carcere di Rimini, ma anche le risposte fornite in termini di cura e riabilitazione. Una terza parte - interventi sul territorio - in cui vengono descritte le attivit? sia di prevenzione sia di contrasto all\u27uso. Risulta particolarmente interessante una prima valutazione delle attivit? realizzata all\u27interno dei piani di zona dei comuni di Rimini e Riccione
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