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1.
Molecules ; 26(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443466

RESUMO

Bees and their products are useful bioindicators of anthropogenic activities and could overcome the deficiencies of air quality networks. Among the environmental contaminants, mercury (Hg) is a toxic metal that can accumulate in living organisms. The first aim of this study was to develop a simple analytical method to determine Hg in small mass samples of bees and beehive products by cold vapor atomic fluorescence spectrometry. The proposed method was optimized for about 0.02 g bee, pollen, propolis, and royal jelly, 0.05 g beeswax and honey, or 0.1 g honeydew with 0.5 mL HCl, 0.2 mL HNO3, and 0.1 mL H2O2 in a water bath (95 °C, 30 min); samples were made up to a final volume of 5 mL deionized water. The method limits sample manipulation and the reagent mixture volume used. Detection limits were lower than 3 µg kg-1 for a sample mass of 0.02 g, and recoveries and precision were within 20% of the expected value and less than 10%, respectively, for many matrices. The second aim of the present study was to evaluate the proposed method's performances on real samples collected in six areas of the Lazio region in Italy.


Assuntos
Abelhas/química , Monitoramento Biológico/métodos , Mercúrio/análise , Espectrometria de Fluorescência/métodos , Animais , Temperatura Baixa , Cucumis melo/química , Confiabilidade dos Dados , Poluição Ambiental/análise , Ácidos Graxos/análise , Mel/análise , Itália , Pólen/química , Própole/análise , Espectrofotometria Atômica/métodos , Ceras/análise
2.
Artigo em Inglês | MEDLINE | ID: mdl-34064840

RESUMO

The aim of the study was to analyze all powdered infant formulas authorized and commercialized in Italy at the time of the study to measure the concentrations of 40 elements, and to estimate the infants' intake of some toxic heavy metals for assessing possible related health risks. For this purpose, an optimized multi-element method was used through inductively coupled plasma mass spectrometry. Be, B, Al, Zr, Nb, Sb, Te, W, V, Cr and As concentrations were

Assuntos
Fórmulas Infantis , Oligoelementos , Humanos , Lactente , Itália , Pós , Medição de Risco , Oligoelementos/análise
3.
Artigo em Inglês | MEDLINE | ID: mdl-33291387

RESUMO

Titanium dioxide is produced or imported into the EU for over one million tons/year. The International Agency for Research on Cancer (IARC) classification is 2B, a possible inhalation carcinogen for humans. This study evaluates urinary biomarkers of oxidative stress in workers of a plant producing TiO2 pigment powder, having 0.25 µm average particle size and an ultrafine fraction, compared to unexposed subjects. Urine samples were collected from forty workers before and after the shift, from six employees of the same company and eighteen volunteers from the same geographical area. Titanium and other metals concentrations were measured by ICP-MS, while DNA, RNA, and protein oxidation products by HPLC/MS-MS. A statistically significant increase was found for the urinary concentration of Al, Cd, Cr, Cu, Fe, Mn, Pb, Ti, and Zr, and for all biomarkers of oxidative stress in post-shift workers' urine samples. Urinary concentrations after the working shift were higher than for employees and volunteers pooled together for Cd, Mn, and Zr, and for the oxidative stress biomarkers 8-oxoGuo, 8-oxodGuo, and 3NO2Tyr. Biomonitoring studies on dose and effect biomarkers for TiO2 occupational exposure provide information useful for protecting workers' health even in conditions that comply with health and safety standards, highlighting reversible effects of chronic exposure at very low doses.


Assuntos
Biomarcadores/urina , Exposição Ocupacional/efeitos adversos , Titânio/urina , Trabalho , Adulto , Indústria Química , Humanos , Estresse Oxidativo/efeitos dos fármacos , Titânio/efeitos adversos , Titânio/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-33321748

RESUMO

Urinary mercury (Hg) levels are suitable to assess long-term exposure to both elemental and inorganic Hg. In this study, the urinary Hg levels of 250 children (aged 6-11 years) from three areas with different anthropogenic impacts in the Rieti province, central Italy, were assessed. The Hg concentrations were in the range of 0.04-2.18 µg L-1 with a geometric mean equal to 0.18 µg L-1 [95% confidence interval (CI), 0.17-0.20 µg L-1] or 0.21 µg g-1 creatinine (95% CI, 0.19-0.23 µg g-1 creatinine), and a reference value calculated as 95th percentile of 0.53 µg L-1 (95% CI, 0.44-0.73 µg L-1) or 0.55 µg g-1 creatinine (95% CI, 0.50-0.83 µg g-1 creatinine). In all cases, urinary Hg data were below the HBM-I values (7 µg L-1 or 5 µg g-1 creatinine) established for urine, while the 95th percentile was above the German Human Biomonitoring Commission's RV95 (0.4 µg L-1) set for children without amalgam fillings. A significant correlation (p < 0.05) was found between creatinine-corrected results and residence area, with higher urinary Hg levels in children living in the industrial area. Multiple linear regression analysis showed that creatinine was the main predictor of urinary Hg.


Assuntos
Exposição Ambiental , Mercúrio , Criança , Creatinina/urina , Amálgama Dentário/química , Exposição Ambiental/análise , Feminino , Humanos , Itália , Modelos Lineares , Masculino , Mercúrio/urina , Valores de Referência , Fatores de Risco
5.
Artigo em Inglês | MEDLINE | ID: mdl-33233360

RESUMO

Children's development and health may be affected by toxic heavy metal exposure or suboptimal essential element intake. This study aimed to provide updated information regarding the concentrations of 41 elements in children's hair (aged under 18) living in a rural area of the Benishangul-Gumuz region, Ethiopia. The highest average levels (as a geometric mean) for toxic heavy metals were obtained for Al (1 mg kg-1), Pb (3.1 mg kg-1), and Ni (1.2 mg kg-1), while the lowest concentrations among the essential elements were found for Co (0.32 mg kg-1), Mo (0.07 mg kg-1), Se (0.19 mg kg-1), and V (0.8 mg kg-1). Hair analysis was combined with a survey to evaluate relationships and variations among subgroups and potential metal exposure predictors. Females showed significantly higher concentrations for most hair elements, excluding Zn, than males, and the 6-11 years age group reported the highest levels for Be, Ce, Co, Fe, La, Li, Mo, and Na. The main predictors of exposure to toxic elements were fish consumption for Hg and drinking water for Ba, Be, Cs, Li, Ni, Tl, and U. The data from this study can be used to develop prevention strategies for children's health and protection in developing countries.


Assuntos
Monitoramento Biológico , Exposição Ambiental/análise , Poluentes Ambientais/análise , Cabelo/química , Metais Pesados/efeitos adversos , Oligoelementos/análise , Adolescente , Animais , Bovinos , Criança , Pré-Escolar , Estudos Transversais , Etiópia , Feminino , Cabelo/metabolismo , Humanos , Lactente , Chumbo/metabolismo , Masculino , Mercúrio/metabolismo , Metais Pesados/metabolismo , Oligoelementos/metabolismo
6.
Molecules ; 25(18)2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32957599

RESUMO

Bee health and beehive products' quality are compromised by complex interactions between multiple stressors, among which toxic elements play an important role. The aim of this study is to optimize and validate sensible and reliable analytical methods for biomonitoring studies and the quality control of beehive products. Four digestion procedures, including two systems (microwave oven and water bath) and different mixture reagents, were evaluated for the determination of the total content of 40 elements in bees and five beehive products (beeswax, honey, pollen, propolis and royal jelly) by using inductively coupled plasma mass and optical emission spectrometry. Method validation was performed by measuring a standard reference material and the recoveries for each selected matrix. The water bath-assisted digestion of bees and beehive products is proposed as a fast alternative to microwave-assisted digestion for all elements in biomonitoring studies. The present study highlights the possible drawbacks that may be encountered during the elemental analysis of these biological matrices and aims to be a valuable aid for the analytical chemist. Total elemental concentrations, determined in commercially available beehive products, are presented.


Assuntos
Metais/análise , Oligoelementos/análise , Animais , Abelhas , Ácidos Graxos/química , Mel , Espectrometria de Massas , Micro-Ondas , Pólen/química , Própole/química , Espectrometria de Fluorescência , Temperatura , Ceras/química
7.
Environ Res ; 191: 110209, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32937173

RESUMO

Air pollution is recognized as the world's largest environmental health risk. In this work we evaluated in vivo the effects of three relevant components of atmospheric dusts (brake dust, wood pellet ash and Saharan dust) employing the animal model Caenorhabditis elegans. Main endpoints of C. elegans such as life span, brood size and oxidative stress were addressed by exposing the nematodes to different dust concentrations. Brake dust and pellet ash affected the life span and increased significantly the oxidative stress of exposed nematodes, while Saharan dust showed no effects. Water soluble and insoluble fractions of these dusts were used to investigate the impact of the single fraction on C. elegans. The two fractions of brake dust and pellet ash exerted different effects on C. elegans endpoints in terms of life span and oxidative stress response. These fractions acted in different ways on the worm susceptibility to infection of two human pathogens (Staphylococcus aureus and Pseudomonas aeruginosa) affecting the sek-1 gene expression. In conclusion, our study showed that C. elegans is a valuable tool to investigate in vivo possible effects of atmospheric dusts.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , África do Norte , Poluentes Atmosféricos/toxicidade , Animais , Caenorhabditis elegans , Poeira , Humanos
8.
Environ Pollut ; 266(Pt 3): 115271, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32814272

RESUMO

The ability of particulate matter (PM) to induce oxidative stress is frequently estimated by acellular oxidative potential (OP) assays, such as ascorbic acid (AA) and 1,4-dithiothreitol (DTT), used as proxy of reactive oxygen species (ROS) generation in biological systems, and particle-bound ROS measurement, such as 2',7'-dichlorodihydrofluorescein (DCFH) assay. In this study, we evaluated the spatial and size distribution of OP results obtained by three OP assays (OPAA, OPDCFH and OPDTT), to qualitative identify the relative relevance of single source contributions in building up OP values and to map the PM potential to induce oxidative stress in living organisms. To this aim, AA, DCFH and DTT assays were applied to size-segregated PM samples, collected by low-pressure cascade impactors, and to PM10 samples collected at 23 different sampling sites (about 1 km between each other) in Terni, an urban and industrial hot-spot of Central Italy, by using recently developed high spatial resolution samplers of PM, which worked in parallel during three monitoring periods (February, April and December 2017). The sampling sites were chosen for representing the main spatially disaggregated sources of PM (vehicular traffic, rail network, domestic heating, power plant for waste treatment, steel plant) present in the study area. The obtained results clearly showed a very different sensitivity of the three assays toward each local PM source. OPAA was particularly sensitive toward coarse particles released from the railway, OPDCFH was sensible to fine particles released from the steel plant and domestic biomass heating, and OPDTT was quite selectively sensitive toward the fine fraction of PM released by industrial and biomass burning sources.


Assuntos
Poluentes Atmosféricos/análise , Material Particulado/análise , Monitoramento Ambiental , Itália , Oxirredução , Estresse Oxidativo , Tamanho da Partícula
9.
Sci Total Environ ; 742: 140590, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32629268

RESUMO

The ability of transplanted lichen Evernia (E.) prunastri (L.) to act as a high spatial biomonitoring tool for 14 polybrominated diphenyl ethers (PBDEs) was evaluated at 23 monitoring sites in a very polluted area in central Italy. The selected area is characterized by the presence of numerous emission sources, such as waste-to-energy plant, steel plant, vehicular traffic, and domestic heating. Transplanted E. prunastri proved to be a useful tool to biomonitor PBDEs, due to its ability to bioaccumulate individual congeners in varying concentrations in relation to the strength of the emission sources present over the territory. PBDEs levels widely ranged from 132 to 24,237 ng kg-1 dry weight, according to the sources of emission located around the monitoring sites. The highest concentrations were detected at the sites close to the municipal solid waste incinerator, steel plant, and high busy roads, confirming their important role as PBDEs emissions sources.


Assuntos
Éteres Difenil Halogenados/análise , Líquens , China , Monitoramento Ambiental , Itália , Resíduos Sólidos
10.
Chemosphere ; 259: 127472, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32599378

RESUMO

In line with the Circular Economy approach, the production of polyhydroxyalkanoate (PHA) with organic waste as the feedstock may a biotechnological application to reduce waste and recover high-value materials. The potential contaminants that could transfer from bio-waste to a PHA include inorganic elements, such as heavy metals. Hence, the total content and migratability of certain elements were evaluated in several PHA samples produced from different origins and following different methods. The total content of certain elements in PHA ranged between 0.0001 (Be) and 49,500 mg kg-1 (Na). The concentrations of some alkaline (Na and K) and alkaline earth (Ca and Mg) metals were highest, which are of little environmental concern. The feedstock type and PHA stabilisation and extraction procedures affected the element contents. Several sets of experiments were conducted to evaluate the migration of elements from the PHA samples under different storage times, temperatures, and pH levels. The total contents of some heavy metals (As, Cd, Fe, Hg, Ni, Pb, and Zn) in PHA produced from fruit waste or crops (commercial PHA) were lower than those in the PHA samples produced from the mixture of the organic fraction of municipal waste and sludge from wastewater treatment. Both the PHA obtained by extraction from wet biomass (acid storage) with aqueous phase extraction reagents and commercial PHA were below the migration limits stipulated by the current Toy Safety Directive and by Commission Regulation (EU) October 2011 on plastic materials and articles intended to come into contact with food under frozen and refrigerated conditions.


Assuntos
Plásticos Biodegradáveis/análise , Plásticos/análise , Resíduos/análise , Biomassa , Biotecnologia , Alimentos , Metais Pesados/análise , Polímeros , Esgotos/química , Eliminação de Resíduos Líquidos , Águas Residuárias
11.
Artigo em Inglês | MEDLINE | ID: mdl-32183479

RESUMO

Small-scale or artisanal mining, using gold-mercury amalgamation to extract gold from ore, is a significant source of exposure for the workers and nearby populations. Few studies on hair mercury (Hg) have been conducted in Africa despite the fact that Africa has several gold deposits. No studies have been conducted in Eritrea that is one of the emerging gold producing countries in Africa. The aim of the study was to assess the Hg concentration in hair samples (n = 120) of a population living in Asmara, capital of Eritrea, and to evaluate the influence of some factors on the Hg levels in hair. Information on age, height, weight, occupation, smoking and fish consumption of participants were collected via questionnaire. Hair Hg concentration was significantly higher among women compared to men (p < 0.001) and among women preparing spicy products in Medeber market compared to those who did other jobs (p = 0.010). These results highlight the need for routine biomonitoring surveys and for health promotion campaigns devoted to local decision makers and workers.


Assuntos
Mercúrio/análise , Adolescente , Adulto , África , Animais , Monitoramento Biológico , Exposição Ambiental/análise , Monitoramento Ambiental , Feminino , Ouro , Humanos , Masculino , Pessoa de Meia-Idade , Mineração , Adulto Jovem
12.
Biol Trace Elem Res ; 197(1): 89-100, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31792772

RESUMO

The aim of the study was to evaluate occupational exposure to 40 elements among a group of Eritrean adults employed at the Medeber metal market by analysing human scalp hair samples and by investigating the role of some predictors (gender, age, and body mass index-BMI) on their levels. Scalp hair samples were collected from 60 subjects (32 subjects working at the Medeber metal market and 28 subjects not working at Medeber and not employed in other industrial or artisanal activities) and were analysed through inductively coupled plasma mass spectrometry to determine the contents of 40 major and trace elements. Information on participants was collected via questionnaire. Significant differences were found in the hair levels of certain elements between subjects working at the Medeber metal market and subjects not exposed. In particular, working at the Medeber metal market increased hair levels of Be, B, Cu, Zn, Mo, Cd, Sb, Tl, Pb, and Fe from 25 to 100%, while reduced Na, K, and Rb levels from 30 to 50%. With multivariate adjustment for age, gender, and BMI, the results confirm that working at Medeber significantly increased the hair levels of Cu, Zn, Sb, Pb, and Fe. This finding reveals the need for more accurate and routine biomonitoring surveys and the necessity of health promotion campaigns both for local decision-makers and workers to increase health promotion and safety in this workplace.


Assuntos
Exposição Ocupacional , Oligoelementos , Adulto , Cabelo/química , Humanos , Metais , Couro Cabeludo/química , Oligoelementos/análise
13.
Materials (Basel) ; 12(24)2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31861202

RESUMO

The aim of this work was to study the potential of food waste materials (banana peel, potato peel, apple peel, lemon peel, coffee waste, decaf coffee waste, grape waste, and carob peel) as low-cost adsorbents for the removal of aliphatic and aromatic volatile organic compounds (VOCs) from wastewater. The ability of examined food waste materials to adsorb VOCs from synthetic multi-component standard solutions was evaluated and the examined food waste materials showed high removal efficiency. Performances of coffee waste, grape waste, and lemon peel were detailed by using Trichloroethylene and p-Xylene in mono-component standard solutions. The adsorption capacity of the three selected food wastes was determined by using linear Langmuir and Freundlich isotherm models. Two errors functions, average percentage error (APE) and the chi-square test (χ2), were used for isotherm optimization prediction. Freundlich isotherm well described the adsorption of VOCs on the considered materials. According to the obtained results, a multilayer, physical, and cooperative adsorption process was hypothesized, particularly evident when the VOCs' concentrations are high. This was confirmed by the high adsorption efficiency percentages (E% > 80%) of VOCs from a real polluted matrix (urban solid waste leachate), containing high concentrations of total organic content.

14.
Environ Int ; 132: 105094, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31484097

RESUMO

Over the last years, various acellular assays have been used for the evaluation of the oxidative potential (OP) of particular matter (PM) to predict PM capacity to generate reactive oxygen (ROS) and nitrogen (RNS) species in biological systems. However, relationships among OP and PM toxicological effects on living organisms are still largely unknown. This study aims to assess the effects of atmospheric PM-selected components (brake dust - BD, pellet ash - PA, road dust - RD, certified urban dust NIST1648a - NIST, soil dust - S, coke dust - C and Saharan dust - SD) on the model plant A. thaliana development, with emphasis on their capacity to induce oxidative stress and root morphology alteration. Before growing A. thaliana in the presence of the PM-selected components, each atmospheric dust has been chemically characterized and tested for the OP through dithiothreitol (DTT), ascorbic acid (AA) and 2',7'-dichlorofluorescin (DCFH) assays. After the exposure, element bioaccumulation in the A. thaliana seedlings, i.e., in roots and shoots, was determined and both morphological and oxidative stress analyses were performed in roots. The results indicated that, except for SD and S, all the tested dusts affected A. thaliana root system morphology, with the strongest effects in the presence of the highest OPs dusts (BD, PA and NIST). Principal component analysis (PCA) revealed correlations among OPs of the dusts, element bioaccumulation and root morphology alteration, identifying the most responsible dust-associated elements affecting the plant. Lastly, histochemical analyses of NO and O2- content and distribution confirmed that BD, PA and NIST induce oxidative stress in A. thaliana, reflecting the high OPs of these dusts and ultimately leading to cell membrane lipid peroxidation.


Assuntos
Poluentes Atmosféricos/toxicidade , Arabidopsis/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/toxicidade , Poluentes do Solo/toxicidade , Arabidopsis/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo
15.
Environ Int ; 130: 104818, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31279184

RESUMO

Potential exposure to toxic elements initially occurs during gestation and after birth via breast milk, which is the principal source of nutrients for infants during the first months of life. In this study, we evaluated whether maternal oral supplementation with a multi-strain probiotic product can protect infants from exposure to arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) via breast milk. In-vitro studies of the bacterial strains present in this probiotic product showed a high bacterial tolerance for As, Cd, Hg, and Pb, and good binding capacity for Cd, Hg, and Pb (72%, 81%, and 64%, respectively) within 1 h of contact. We evaluated concentrations (5 mg L-1 for Cd and Pb, and 2 mg L-1 for Hg) that largely exceeded the provisional tolerable weekly intake of these toxic elements via food or water applicable for human consumption. Changes in the levels of these elements in breast milk and newborn stools were evaluated in the control (orally supplemented with placebo) and experimental (orally supplemented with probiotic) groups at birth (t0), 15 days (t15), and 30 days (t30) after delivery. Elemental analysis of breast milk did not show significant differences between the control and experimental groups at different stages of lactation; however, stool samples obtained from newborns of mothers supplemented with the probiotic product showed that Cd levels were significantly reduced (by 26%) at t15 compared with the levels of the controls. Our data did not show an association between concentration of toxic elements in breast milk and that in newborn stools. Indeed, the concentration of Cd, Hg, and Pb in breast milk decreased during the lactation period, whereas the levels of these elements in newborn stools were stable over time. Although our in-vitro data indicate that the consortium of these probiotic strains can absorb toxic compounds, this study was limited by its small sample size and potential uncontrolled confounding effects, such as maternal diet and lifestyle. Therefore, we could not confirm whether prophylactic use of this probiotic product can reduce the absorption of toxic elements. The risk assessment in the studied population evidenced a margin of exposure (MOE) of 1, or between 1 and 10 for Pb, and lower than 50 for As. This poses a potential risk for breastfed infants, indicating that interventions aimed to avoid breastfeeding-related health risks remain a major challenge in public health.


Assuntos
Monitoramento Biológico/métodos , Fezes/química , Metais Pesados , Leite Humano/química , Probióticos/uso terapêutico , Adulto , Intoxicação por Metais Pesados/prevenção & controle , Humanos , Lactente
16.
Anal Chem ; 91(11): 7025-7031, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31059231

RESUMO

In this work, a novel multiway approach by spectroscopy and thermogravimetry associated with chemometrics is developed, providing a multiparametric characterization of vitreous humor as a function of the time since death. Estimation of the precise time since death was performed on hospital deaths occurred in casualty, by medico-legal and post mortem examination, with no metabolic disorders. Micro and macro elements in vitreous specimens were determined by ICP-OES and were found to be diagnostic in predicting the post mortem interval (PMI). The percentage of bulk and bound water provided by thermal analysis investigation was correlated to spectroscopic analysis, and chemometric tools were used to compare results and to develop a model of prediction of PMI. The study reveals a significant role of P, S, and Mg in addition to the potassium concentration in determining the death interval and permits increased accuracy with respect to conventional procedures and allows the investigation of PMI to be extended to 15 days.


Assuntos
Análise Espectral/métodos , Corpo Vítreo/química , Autopsia , Feminino , Humanos , Magnésio/análise , Masculino , Fósforo/análise , Potássio/análise , Reprodutibilidade dos Testes , Termogravimetria , Fatores de Tempo
17.
Sci Total Environ ; 653: 1192-1203, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30759559

RESUMO

A variety of appliances operated by brush electric motors, widely used in indoor environments, emit nanoparticles (NPs). Due to electric arc discharge during the operation of such motors, some NPs contain copper (Cu). Their dimensions are the same of those found in brain tissue samples by other authors who speculated their possible translocation to brain through olfactory bulb. Cu has been reported to play an important role in the etiopathogenesis of Alzheimer's disease. Thus, the present study was performed to 1. estimate by means of Multiple-Path Particle Dosimetry model the doses of NPs released by electric appliances that can potentially deposit on the olfactory bulb; 2. investigate the morphology and the composition of particles emitted by some electric appliances daily used in indoor environments; 3. monitor for a long time period the Cu contamination of indoor environments due to this kind of appliances. About 106-107 NPs deposit on the olfactory bulb during the operation (1.5-6 min) of such appliances, with a major contribution due to 10-20 nm NPs. HR-FESEM characterization confirmed the presence of such NPs, that were observed both as individual particles (20-40 nm) and aggregated to form particles in the µm sizes range. XEDS microanalysis revealed the presence of Cu together with other elements. Relevant daily contamination of indoor environments due to these appliances has been confirmed by monitoring throughout a year the Cu content of PM10 samples collected both indoor and outdoor private dwellings. Cu was present in great part as an insoluble form. This means that, following protracted exposure, Cu NPs of such origin may undergo tissue accumulation. This is cause of concern because general population is chronically exposed to such Cu nanoparticles in indoor environments and in view of the role assigned to Cu in the development of neurological disorders.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Cobre/análise , Nanopartículas Metálicas/análise , Simulação por Computador , Cobre/química , Monitoramento Ambiental , Utensílios Domésticos , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Bulbo Olfatório/química , Tamanho da Partícula
18.
Indoor Air ; 29(2): 276-290, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30580463

RESUMO

This study aimed at surveying lower secondary schools in southern Italy, in a highly polluted area. A community close to an industrial area and three villages in rural areas was investigated. Indoor temperature, relative humidity (RH), gaseous pollutants (CO2 and NO2 ), selected biological pollutants in indoor dust, and the indoor/outdoor mass concentration and elemental composition of PM2.5 were ascertained. Temperature and RH were within, or close to, the comfort range, while CO2 frequently exceeded the threshold of 1000 ppm, indicating inadequate air exchange rate. In all the classrooms, median NO2 levels were above the WHO threshold value. Dermatophagoides p. allergen concentration was below the sensitizing threshold, while high endotoxin levels were detected in the classrooms, suggesting schools may produce significant risks of endotoxin exposure. Concentration and solubility of PM2.5 elements were used to identify the sources of indoor particles. Indoor concentration of most elements was higher than outdoors. Resuspension was responsible for the indoor increase in soil components. For elements from industrial emission (Cd, Co, Ni, Pb, Sb, Tl, V), the indoor concentration depended on penetration from the outside. For these elements, differences in rural vs industrial concentrations were found, suggesting industrial sources may influence indoor air quality nearby schools.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Monóxido de Carbono/análise , Poeira/análise , Metais Pesados/análise , Dióxido de Nitrogênio/análise , Material Particulado/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Humanos , Umidade , Região do Mediterrâneo , Tamanho da Partícula , População Rural , Instituições Acadêmicas , Sicília , Temperatura , Ventilação
19.
Food Chem ; 278: 17-25, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30583357

RESUMO

An analytical method for determining seleno-methionine (SeMet), methyl-seleno-cysteine and seleno-cystine in extra-virgin olive oil (EVOO) was developed and validated. EVOO sample (15 g) was diluted with hexane, extracted with methanol/water 80:20 (v/v), and cleaned up by a reversed phase/strong cation exchange solid phase extraction. Analysis was performed by chiral hydrophilic interaction liquid chromatography-tandem mass spectrometry. Process efficiency ranged between 49 and 97% and trueness between 87 and 126%, with intermediate precision, expressed as standard deviation, lower than 10%. Method detection limits (MDLs) and method quantification limits (MQLs) were lower than 1 µg kg-1. Thirty-two EVOO samples from different Italian regions were analyzed for both total Se and single seleno-amino acids determination. Only l-SeMet was found at level MQL (0.2 µg kg-1)-1.42 µg kg-1 in ten samples, while total Se was in the range of MDL-9.1 µg kg-1. Concentration of l-SeMet (5-6% of total Se) and total Se correlated very well to each other (R2 = 0.995).


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Azeite de Oliva/química , Selenocisteína/análise , Selenometionina/análise , Espectrometria de Massas em Tandem/métodos , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Selenocisteína/isolamento & purificação , Selenometionina/isolamento & purificação , Extração em Fase Sólida , Estereoisomerismo
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