1,872 research outputs found

    Profiles and species of Mn, Fe and trace metals in soils near a ferromanganese plant in Bagnolo Mella (Brescia, IT)

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    For the last forty-five years (from 1974 to present) ferroalloy production in Bagnolo Mella, Northern Italy, has generated particulate emissions enriched in potentially toxic metals and metalloids including arsenic (As), lead (Pb) and manganese (Mn). Of these, Mn is unique in that it has a significant background concentration and is seldom studied as a contaminant but is potentially a significant toxin derived from dusts regionally. Here we examine the distribution, redistribution, speciation and bioavailability of the Mn-contaminated top soils affected by atmospheric emissions adjacent to the ferroalloy plant. Four sites, variably located in the study area in terms of both distance and direction from the plant, were considered as representative of increasing levels of industrial influence. Soil profiles showed that metal concentrations (measured by X-ray fluorescence) varied considerably by location, i.e. higher in the sites closer to the plant and also at the surface level, although distributed throughout the top 15 cm, suggesting appreciable redistribution possibly due to soil mixing or infiltration. Most metal concentrations were correlated, except Mn which was independent and more variable across the sites than the other elements. Sequential chemical extractions indicated that Pb was primarily associated with Mn oxides, while As was most significantly associated with iron oxides. When Mn concentration significantly exceeded background levels, it was present in phases that were resistant to acid dissolution, very different from typical uncontaminated soils. X-ray Absorption Near Edge Spectroscopy (XANES) analyses suggested this recalcitrant Mn phase is likely a Mn-bearing spinel such as magnetite, that can be particularly toxic if ingested or inhaled. These first results highlight the legacy of ferroalloy production on surrounding soils, as well as the importance of Mn speciation for soil apportionment evaluation and human exposure estimation

    COVID-19 incidence and mortality in Lombardy, Italy: An ecological study on the role of air pollution, meteorological factors, demographic and socioeconomic variables

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    Lombardy, the most populated and industrialized Italian region, was the epicentre of the first wave (March and April 2020) of COVID-19 in Italy and it is among the most air polluted areas of Europe. We carried out an ecological study to assess the association between long-term exposure to particulate matter (PM) and nitrogen dioxide (NO2) on COVID-19 incidence and all-cause mortality after accounting for demographic, socioeconomic and meteorological variables. The study was based on publicly available data. Multivariable negative binomial mixed regression models were fitted, and results were reported in terms of incidence rate ratios (IRRs) and standardized mortality ratios (SMR). The effect of winter temperature and humidity was modelled through restricted cubic spline. Data from 1439 municipalities out of 1507 (95%) were included in the analyses, leading to a total of 61,377 COVID-19 cases and 40,401 deaths from all-causes collected from February 20th to April 16th and from March 1st to April 30th, 2020, respectively. Several demographic and socioeconomic variables resulted significantly associated with COVID-19 incidence and all-cause mortality in a multivariable fashion. An increase in average winter temperature was associated with a nonlinear decrease in COVID-19 incidence and all-cause mortality, while an opposite trend emerged for the absolute humidity. An increase of 10 μg/m3 in the mean annual concentrations of PM2.5 and PM10 over the previous years was associated with a 58% and 34% increase in COVID-19 incidence rate, respectively. Similarly, a 10 μg/m3 increase of annual mean PM2.5 concentration was associated with a 23% increase in all-cause mortality. An inverse association was found between NO2 levels and COVID-19 incidence and all-cause mortality. Our ecological study showed that exposure to PM was significantly associated with the COVID-19 incidence and excess mortality during the first wave of the outbreak in Lombardy, Italy

    Topological network properties of resting-state functional connectivity patterns are associated with metal mixture exposure in adolescents

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    IntroductionAdolescent exposure to neurotoxic metals adversely impacts cognitive, motor, and behavioral development. Few studies have addressed the underlying brain mechanisms of these metal-associated developmental outcomes. Furthermore, metal exposure occurs as a mixture, yet previous studies most often consider impacts of each metal individually. In this cross-sectional study, we investigated the relationship between exposure to neurotoxic metals and topological brain metrics in adolescents. MethodsIn 193 participants (53% females, ages: 15-25 years) enrolled in the Public Health Impact of Metals Exposure (PHIME) study, we measured concentrations of four metals (manganese, lead, copper, and chromium) in multiple biological media (blood, urine, hair, and saliva) and acquired resting-state functional magnetic resonance imaging scans. Using graph theory metrics, we computed global and local efficiency (global:GE; local:LE) in 111 brain areas (Harvard Oxford Atlas). We used weighted quantile sum (WQS) regression models to examine association between metal mixtures and each graph metric (GE or LE), adjusted for sex and age. ResultsWe observed significant negative associations between the metal mixture and GE and LE [beta GE = -0.076, 95% CI (-0.122, -0.031); beta LE= -0.051, 95% CI (-0.095, -0.006)]. Lead and chromium measured in blood contributed most to this association for GE, while chromium measured in hair contributed the most for LE. DiscussionOur results suggest that exposure to this metal mixture during adolescence reduces the efficiency of integrating information in brain networks at both local and global levels, informing potential neural mechanisms underlying the developmental toxicity of metals. Results further suggest these associations are due to combined joint effects to different metals, rather than to a single metal

    Heavy Metals in Soil and Salad in the Proximity of Historical Ferroalloy Emission

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    Emissions of manganese (Mn), lead (Pb), iron (Fe), zinc (Zn), copper (Cu) from ferro-alloy operations has taken place in Valcamonica, a pre-Alp valley in the province of Brescia, Italy, for about a century until 2001. Metal concentrations were measured in the soil of local home gardens and in the cultivated vegetables. Soil analysis was carried out using a portable X-Ray Fluorescence (XRF) spectrometer in both surface soil and at 10 cm depth. A subset of soil samples (n = 23) additionally was analysed using the modified BCR sequential extraction method and ICP-OES for intercalibration with XRF (XRF Mn = 1.33 * total OES Mn – 71.8; R = 0.830, p < 0.0001). Samples of salads (Lactuca sativa and Chichorium spp.) were analyzed with a Total Reflection X-Ray Fluorescence (TXRF) technique. Vegetable and soil metal measurements were performed in 59 home gardens of Valcamonica, and compared with 23 gardens from the Garda Lake reference area. Results indicate significantly higher levels of soil Mn (median 986 ppm vs 416 ppm), Pb (median 46.1 ppm vs 30.2 ppm), Fe (median 19,800 ppm vs 13,100 ppm) in the Valcamonica compared to the reference area. Surface soil levels of all metals were significantly higher in surface soil compared to deeper soil, consistent with atmospheric deposition. Significantly higher levels of metals were shown also in lettuce from Valcamonica for Mn (median 53.6 ppm vs 30.2) and Fe (median 153 vs 118). Metals in Chichorium spp. did not differ between the two areas. Surface soil metal levels declined with increasing distance from the closest ferroalloy plant, consistent with plant emis- sions as the source of elevated soil metal levels. A correlation between Mn concentrations in soil and lettuce was also observed. These data show that historic ferroalloy plant activity, which ended nearly a decade before this study, has contributed to the persistence of increased Mn levels in locally grown vegetables. Further research is needed to assess whether this increase can lead to adverse effects in humans and plants especially for Mn, an essential element that can be toxic in humans when exceeding the homeostatic ranges

    Relationships of Nutritional Factors and Agrochemical Exposure with Parkinson's Disease in the Province of Brescia, Italy

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    Environmental exposures to agrochemicals and nutritional factors may be associated with Parkinson's Disease (PD). None of the studies to date has examined the combined effects of diet and agricultural chemical exposure together. To address these research gaps, we aimed to assess the association of nutritional factors and agrochemical exposure with the risk of PD. A hospital-based case-control study was conducted. Multivariable logistic regressions were used to estimate the association of nutritional and agrochemical exposures with PD, adjusting for gender, age, socio-economic status, head injury, family history, smoking, metals exposure, and alpha-synuclein gene polymorphism. Weighted Quantile Sum (WQS) regression was applied to examine the effect of dietary components as a mixture. We recruited 347 cases and 389 controls. Parent history of PD (OR = 4.15, 95%CI: 2.10, 8.20), metals exposure (OR = 2.50, 95%CI: 1.61-3.89), SNCA rs356219 polymorphism (OR = 1.39, 95%CI: 1.04-1.87 for TC vs. TT; OR = 2.17, 95%CI: 1.43-3.28 for CC vs. TT), agrochemical exposures (OR = 2.11, 95%CI: 1.41-3.16), and being born in the Brescia province (OR = 1.83, 95%CI: 1.17-2.90) were significantly associated with PD. Conversely, fish intake and coffee consumption had a protective effect. The study confirmed the role of environmental exposures in the genesis of PD. Fish intake and coffee consumption are protective factors even when agricultural chemical exposures exist. Genetic factors and metals exposure were confirmed as risk factors for PD

    Neuro-environmental interactions: a time sensitive matter

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    Introduction: The assessment of resting state (rs) neurophysiological dynamics relies on the control of sensory, perceptual, and behavioral environments to minimize variability and rule-out confounding sources of activation during testing conditions. Here, we investigated how temporally-distal environmental inputs, specifically metal exposures experienced up to several months prior to scanning, affect functional dynamics measured using rs functional magnetic resonance imaging (rs-fMRI). Methods: We implemented an interpretable XGBoost-shapley additive explanation (SHAP) model that integrated information from multiple exposure biomarkers to predict rs dynamics in typically developing adolescents. In 124 participants (53% females, ages, 13-25 years) enrolled in the public health impact of metals exposure (PHIME) study, we measured concentrations of six metals (manganese, lead, chromium, copper, nickel, and zinc) in biological matrices (saliva, hair, fingernails, toenails, blood, and urine) and acquired rs-fMRI scans. Using graph theory metrics, we computed global efficiency (GE) in 111 brain areas (Harvard Oxford atlas). We used a predictive model based on ensemble gradient boosting to predict GE from metal biomarkers, adjusting for age and biological sex. Results: Model performance was evaluated by comparing predicted versus measured GE. SHAP scores were used to evaluate feature importance. Measured versus predicted rs dynamics from our model utilizing chemical exposures as inputs were significantly correlated (p < 0.001, r = 0.36). Lead, chromium, and copper contributed most to the prediction of GE metrics. Discussion: Our results indicate that a significant component of rs dynamics, comprising approximately 13% of observed variability in GE, is driven by recent metal exposures. These findings emphasize the need to estimate and control for the influence of past and current chemical exposures in the assessment and analysis of rs functional connectivity

    Efficient aberrations pre-compensation and wavefront correction with a deformable mirror in the middle of a petawatt-class CPA laser system

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    AbstractIn this paper, we describe the experimental validation of the technique of correction of wavefront aberration in the middle of the laser amplifying chain. This technique allows the correction of the aberrations from the first part of the laser system, and the pre-compensation of the aberrations built in the second part. This approach will allow an effective aberration management in the laser chain, to protect the optical surfaces and optimize performances, and is the only possible approach for multi-petawatt laser system from the technical and economical point of view. This approach is now possible after the introduction of new deformable mirrors with lower static aberrations and higher dynamic than the standard devices

    Manganese concentrations in soil and settled dust in an area with historic ferroalloy production

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    Ferroalloy production can release a number of metals into the environment, of which manganese (Mn) is of major concern. Other elements include lead, iron, zinc, copper, chromium, and cadmium. Manganese exposure derived from settled dust and suspended aerosols can cause a variety of adverse neurological effects to chronically exposed individuals. To better estimate the current levels of exposure, this study quantified metal levels in dust collected inside homes (n=85), outside homes (n=81), in attics (n=6), and in surface soil (n=252) in an area with historic ferroalloy production. Metals contained in indoor and outdoor dust samples were quantified using inductively coupled plasma optical emission spectroscopy while attic and soil measurements were made with a XRF instrument. Mean Mn concentrations in soil (4600 μg/g) and indoor dust (870 μg/g) collected within 0.5 km of a plant exceeded levels previously found in suburban and urban areas, but did decrease outside 1.0 km to the upper end of background concentrations. Mn concentrations in attic dust were approximately 120 times larger than other indoor dust levels, consistent with historical emissions that yielded high airborne concentrations in the region. Considering the potential health effects that are associated with chronic manganese inhalation and ingestion exposure, remediation of soil near the plants and frequent, on-going hygiene indoors may decrease residential exposure and the likelihood of adverse health effects

    Cortical complexity in world trade center responders with chronic posttraumatic stress disorder

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    Approximately 23% of World Trade Center (WTC) responders are experiencing chronic posttraumatic stress disorder (PTSD) associated with their exposures at the WTC following the terrorist attacks of 9/11/2001, which has been demonstrated to be a risk factor for cognitive impairment raising concerns regarding their brain health. Cortical complexity, as measured by analyzing Fractal Dimension (FD) from T1 MRI brain images, has been reported to be reduced in a variety of psychiatric and neurological conditions. In this report, we hypothesized that FD would be also reduced in a case-control sample of 99 WTC responders as a result of WTC-related PTSD. The results of our surface-based morphometry cluster analysis found alterations in vertex clusters of complexity in WTC responders with PTSD, with marked reductions in regions within the frontal, parietal, and temporal cortices, in addition to whole-brain absolute bilateral and unilateral complexity. Furthermore, region of interest analysis identified that the magnitude of changes in regional FD severity was associated with increased PTSD symptoms (reexperiencing, avoidance, hyperarousal, negative affect) severity. This study confirms prior findings on FD and psychiatric disorders and extends our understanding of FD associations with posttraumatic symptom severity. The complex and traumatic experiences that led to WTC-related PTSD were associated with reductions in cortical complexity. Future work is needed to determine whether reduced cortical complexity arose prior to, or concurrently with, onset of PTSD
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