Size-segregated content of heavy metals and polycyclic aromatic hydrocarbons in airborne particles emitted by indoor sources.

Indoor air quality is negatively affected by the emission of different combustion sources releasing airborne particles and related particle-bound toxic compounds (e.g., heavy metals and polycyclic aromatic hydrocarbons). To date, very few studies focused on the chemical characterization of the airborne particles emitted by indoor sources were carried out; moreover, no data on their size-resolved chemical compositions are available. In the present study, an experimental analysis aimed at determining the size-segregated content of heavy metals and polycyclic aromatic hydrocarbons in airborne particles (including sub-micrometric ones) emitted by widely-used indoor combustion sources (i.e., incenses, candles, mosquito-coils, and cooking activities) was carried out. To this purpose, airborne particles were collected through an electric low-pressure impactor and were post-analyzed by means of chromatography-mass spectrometry and atomic emission spectrometry techniques. Results of the analyses showed that the chemical composition of the emitted particles is not invariant to the particle size, indeed, an important contribution of sub-micrometric particle range to the total mass of chemical compounds emitted by the sources was noticed. These findings also demonstrated that significant underestimations of particle-bound compounds depositing in the lungs could occur if size-dependent compositions are not adopted.

Levels of Polychlorinated Dibenzo-p-Dioxins/Furans and Polychlorinated Biphenyls in Free-Range Hen Eggs in Central Italy and Estimated Human Dietary Exposure.

ABSTRACT: The aim of the present study was to evaluate the contamination levels of some classes of persistent organic pollutants in free-range hen eggs and to estimate the related human dietary exposure in a site of national interest, characterized by a serious state of environmental pollution in the Bussi sul Tirino area in central Italy. For these purposes, 17 samples of free-range hen eggs collected in home-producing farms located in the site of national interest territory were analyzed for 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), 12 dioxin-like polychlorinated biphenyls (dl-PCBs), and 6 non-dioxin-like PCBs (ndl-PCBs). Dietary exposure was assessed assuming a standard consumption of eggs per week. The concentration of ∑PCDD/Fs plus dl-PCBs ranged from 0.463 to 8.028 pg toxic equivalent g-1 fat, whereas the mean contamination level of the ∑ndl-PCBs ranged from 0.234 to 7.741 ng toxic equivalent g-1 fat. PCDD/Fs and PCBs contamination levels were lower than maximum values established by the Commission Regulation (European Union) 1259/2011, except for one sample. The estimated weekly intake, calculated to evaluate the contribution in terms of the monitored pollutants of the locally produced eggs to the diet, was lower than the tolerable weekly intake established by the European Food Safety Authority.

Indoor exposure to particles emitted by biomass-burning heating systems and evaluation of dose and lung cancer risk received by population.

Homes represent a critical microenvironment in terms of air quality due to the proximity to main particle sources and the lack of proper ventilation systems. Biomass-fed heating systems are still extensively used worldwide, then likely emitting a significant amount of particles in indoor environments. Nonetheless, research on biomass emissions are limited to their effects on outdoor air quality then not properly investigating the emission in indoor environments. To this purpose, the present paper aims to evaluate the exposure to different airborne particle metrics (including both sub- and super-micron particles) and attached carcinogenic compounds in dwellings where three different heating systems were used: open fireplaces, closed fireplaces and pellet stoves. Measurements in terms of particle number, lung-deposited surface area, and PM fraction concentrations were measured during the biomass combustion activities, moreover, PM10 samples were collected and chemically analyzed to obtain mass fractions of carcinogenic compounds attached onto particles. Airborne particle doses received by people exposed in such environments were evaluated as well as their excess lung cancer risk. Most probable surface area extra-doses received by people exposed to open fireplaces on hourly basis (56 mm2 h-1) resulted one order of magnitude larger than those experienced for exposure to closed fireplaces and pellet stoves. Lifetime extra risk of Italian people exposed to the heating systems under investigation were larger than the acceptable lifetime risk (10-5): in particular, the risk due to the open fireplace (8.8 × 10-3) was non-negligible when compared to the overall lung cancer risk of typical Italian population.

Second-hand smoke exposure generated by new electronic devices (IQOS® and e-cigs) and traditional cigarettes: submicron particle behaviour in human respiratory system.

Passive exposure profiles to submicronic particles (SMPs, 5.6-560 nm) of traditional cigarettes and new electronic commercial devices (e-cig and IQOS®, a new heat-not-burn smoking device) were compared. During smoking, SMPs released by traditional cigarettes resulted four-times higher than those released by electronic and heat-not-burn devices and remained high for at least one hour, while SMPs values returned immediately similar to background for electronic and heat-not-burn devices. In all experiments, approximately half of SMPs resulted so small to reach the alveolar region.

A benchmark for numerical scheme validation of airborne particle exposure in street canyons.

Measurements of particle concentrations and distributions in terms of number, surface area, and mass were performed simultaneously at eight sampling points within a symmetric street canyon of an Italian city. The aim was to obtain a useful benchmark for validation of wind tunnel experiments and numerical schemes: to this purpose, the influence of wind directions and speeds was considered. Particle number concentrations (PNCs) were higher on the leeward side than the windward side of the street canyon due to the wind vortex effect. Different vertical PNC profiles were observed between the two canyon sides depending on the wind direction and speed at roof level. A decrease in particle concentrations was observed with increasing rooftop wind speed, except for the coarse fraction indicating a possible particle resuspension due to the traffic and wind motion. This study confirms that particle concentration fields in urban street canyons are strongly influenced by traffic emissions and meteorological parameters, especially wind direction and speed.

[Submicron particles in smoke resulting from welding alloys and cast alloy in metalworking industry]. / Particelle submicrometriche in fumi derivanti da operazioni di saldatura e di fusione di leghe metalliche.

BACKGROUND: The toxicity of welding fumes depends on both chemical composition and ability to penetrate and deposit deeply in the lungs. Their penetration and deposition in the regions of the respiratory system is mainly determined by their size. OBJECTIVES: The knowledge of the size distribution of welding fumes is a crucial information towards the estimate of the doses of toxic compounds delivered into the respiratory tract. METHODS: Particle number size distribution was continuously measured during different welding operations by means of a Fast Mobility Particle Sizer, which counts and classifies particles, according to their electrical mobility, in 32 size-channels, in the range from 5.6 to 523 nm, with is time resolution. RESULTS: The temporal evolution of submicrometric particles (6-523 nm), nucleation mode particles (6-16 nm) and the fraction 19-523 nm before, during and after the welding operations performed with/without local exhaust ventilation are reported and extensively discussed. Before welding, nucleation mode particles represent about 7% of submicrometric particles; after about 40 s from the welding start, the percent contribution of nucleation mode particles increases to 60%. Total and nucleation mode particle concentrations increase from 2.1 x 10(4) to 2.0 x 10(6) and from 1.6 x 10(3) to 1.0 x 10(6), respectively. CONCLUSIONS: The temporal variation of the particle number size distribution across the peaks, evidences the strong and fast-evolving contribution of nucleation mode particles: peak values are maintained for less than 10 s. The implication of such contribution on human health is linked to high deposition efficiency of the submicrometric particles in the alveolar interstitial region of the human respiratory system, where gas exchange occurs.

Relevance of aerosol size spectrum analysis as support to qualitative source apportionment studies.

This work presents a diagnostic methodology in support to source apportionment studies to identify remote and local pollution sources. It is based on the temporal analysis of both PM size distributions and PM size fraction correlation along with natural radioactivity measurements as index of Planetary Boundary Layer dynamic. A correlation drop is indicative of changing aerosol sources. When this observation is coupled with decreasing level of natural radioactivity and increasing aerosol concentration, be it coarse or fine, it is indicative of the inflow of remote polluted air masses. The methodology defines in which size range operates the contribution of remote pollution sources. It was applied to two PM10 pollution episodes: the first involved the advection of coarse PM, the second entailed the inflow of two air masses, one transporting coarse dust and the other fine PM. Dust models and backward trajectories analysis confirmed such results, indicating the air mass provenience.

Characterization of a suspect nuclear fuel rod in a case of illegal international traffic of fissile material.

This case study describes the characterization of a suspect rod of nuclear fuel seized in Italy: on request of the coroner, the characterization concerned the kind and the conditions of the rod, the amount and the specific characteristics of the species present in it, with particular attention to their possible use chemical and/or nuclear plants. The methodology used was based on radiochemical analyses (gammagraphic and gamma-spectrometry) whereas the comparison was performed by means of a fuel reference element working in the TRIGA nuclear reactor at Research Center of ENEA-Casaccia. The results show clearly how the exhibit was an element of nuclear fuel, how long it was irradiated, and the amount of (239)Pu produced and the (235)U consumed. Finally, even if the seized rod was briefly radiated at the "zero power" and traces of fission products and plutonium were found, it would be still usable as "fresh" fuel in a reactor type TRIGA if it had not been intercepted by Italian police authorities.

Dimensional and chemical characterization of particles at a downwind receptor site of a waste-to-energy plant.

In the last years numerous epidemiological studies were carried out to evaluate the effects of particulate matter on human health. In industrialized areas, anthropogenic activities highly contribute to the fine and ultrafine particle concentrations. Then, it is important to characterize the evolution of particle size distribution and chemical composition near these emission points. Waste incineration represents a favorable technique for reducing the waste volume. However, in the past, municipal waste incinerators (MWIs) had a bad reputation due to the emission of toxic combustion byproducts. Consequently, the risk perception of the people living near MWIs is very high even if in Western countries waste incineration has nowadays to be considered a relatively clean process from a technical point of view. The study here presented has an exemplary meaning for developing appropriate management and control strategies for air quality in the surrounding of MWIs and to perform exposure assessment for populations involved. Environment particles were continuously measured through a SMPS/APS system over 12 months. The monitoring site represents a downwind receptor of a typical MWI. Furthermore, elements and organic fractions were measured by means of the Instrumental Neutron Activation Analysis and using dichotomous and high volume samplers. Annual mean values of 8.6 x 10(3)+/-3.7 x 10(2)part.cm(-3) and 31.1+/-9.0 microg m(-3) were found for number and mass concentration, typical of a rural site. Most of the elements can be attributed to long-range transport from other natural and/or anthropogenic sources. Finally, the Polycyclic Aromatic Hydrocarbons present low concentrations with a mean value of 24.6 ng m(-3).

[Identification of the carbonaceous fraction of particulate matter pollution in the urban area of Rome--Part I]. / Caratterizzazione della frazione carboniosa dell'inquinamento particellare nell'area urbana di Roma Parte I.

BACKGROUND: Particulate Matter pollution in urban areas is due to different sources and varies in composition, where the carbonaceous fraction is of particularly importance due to its effects on human health and the climate. OBJECTIVES: to study the contribution of the carbonaceous fraction in PM10 pollution in the urban area of Rome and identify the composition of its organic fraction. METHODS: Separation of Elemental Carbon (EC) from Organic Carbon (OC) was carried out by means of a 5400 Ambient Carbon Particulate Monitor 5400 based on a two-step combustion procedure. RESULTS: The carbonaceous fraction in central Rome accounted for 30-40% of PM10 at ground level and consisted of 60-70% Elemental Carbon and 30-40% Organic Carbon. Polycyclic Aromatic Hydrocarbons, n-Alkanes and n-Alkanoic acids were identified among the constituents of the OC fraction, sulphates, nitrate and ammonia in the hydrosoluble inorganic fraction and heavy metals (Cd, Cr, Fe, Ni, Pb, V, Zn) in the non-hydrosoluble inorganic fraction. PM10 temporal trends were interpreted using measurement of the natural radioactivity (radon and its short-lived decay products) as tracer of the dynamic properties of the atmospheric boundary layer. CONCLUSIONS: Carbonaceous particulate matter is a fundamental parameter to evaluate atmospheric pollution due to combustion processes and can be considered as a specific index of motor vehicle traffic pollution. Its separation into elemental carbon, of primary origin, and organic carbon, of both primary and secondary origin, is toxicologically signficant and in order to study the formation mechanisms of photochemical pollution.

[Air quality and human health: PM10 and respiratory diseases]. / Qualità dell'aria e salute: particolato atmosferico PM10 e malattie respiratorie.

In this paper a comparison between the air quality data collected in urban and rural areas is performed taking in account the PM10 levels allowed in the European Union and in the world and is related to the increase of respiratory diseases. The parameters considered are essentially due to the anthropogenic primary pollution: particulate matter PM10, benzene and toluene, CO and Polycyclic Aromatic Hydrocarbons.

[Spa and climate therapy in chronic obstructive pulmonary diseases]. / Possibilità crenoterapiche e climatoterapiche nelle malattie ostruttive polmonari croniche.

The authors remind the main epidemiological and clinical findings of Chronic Obstructive Pulmonary Disease (COPD); the prevalence and incidence of COPD is increasing and COPD is now the IV cause of death in the world. Moreover, it is cause of increasing pharmaceutic and hospital charges. COPD has multifactorial etiology, linked to genetic and exogenous factors, as tobacco smoke, air pollution, microbial infections and cold. The GOLD guide lines of the medical therapy of the COPD are showed. The spa therapy of COPD is based on the inhalation use of mineral water, mainly sulphurous and salsojodic. Sulphurous mineral waters have vasodilating activity on vessels of bronchial mucose, improving its trophic state, and increase the production of secretory IgA and muco-ciliary clearance; they have fluidificant activity on bronchial secretion. Clinical trials showed improvement of cough, sputum and functional indexes as FEV1 and CV. Salsojodic mineral waters increase the fluidity of the bronchial mucus, muco-ciliary clearance and the trophism of the bronchial mucose. The authors remind the properties of sulphate and bicarbonate mineral waters in the spa therapy of COPD. Finally authors refer about some effects of spa therapy and climatic-environmental situations on COPD morbidity.

Functional analysis of regulatory elements controlling the expression of the ecdysone-regulated Drosophila ng-1 gene.

The steroid hormone ecdysone controls multiple aspects of insect development, including larval moults and metamorphosis, and can induce specific genetic responses in different tissues. The definition of the molecular mechanisms able to mediate this tissue-specific responsiveness may greatly contribute to understanding how such an accurate genetic response is achieved. In this work we have identified, by transgenic analysis, the regulatory elements directing the expression of ng-1, an ecdysone-regulated Drosophila gene showing a highly specific developmental expression profile. Our results show that an ecdysone-responsive element located within the ng-1 coding region is necessary for high-level gene expression, whereas the gene's spatial and temporal expression profile is fully controlled by a distinct upstream regulatory region. This region binds a set of transcriptional factors, including the FKH regulatory protein, which can potentially modulate the ecdysone genetic regulated response.

The ecdysone regulatory pathway controls wing morphogenesis and integrin expression during Drosophila metamorphosis.

Drosophila imaginal discs are specified and patterned during embryonic and larval development, resulting in each cell acquiring a specific fate in the adult fly. Morphogenesis and differentiation of imaginal tissues, however, does not occur until metamorphosis, when pulses of the steroid hormone ecdysone direct these complex morphogenetic responses. In this paper, we focus on the role of ecdysone in regulating adult wing development during metamorphosis. We show that mutations in the EcR ecdysone receptor gene and crooked legs (crol), an ecdysone-inducible gene that encodes a family of zinc finger proteins, cause similar defects in wing morphogenesis and cell adhesion, indicating a role for ecdysone in these morphogenetic responses. We also show that crol and EcR mutations interact with mutations in genes encoding integrin subunits-a family of alphabeta heterodimeric cell surface receptors that mediate cell adhesion in many organisms. alpha-Integrin transcription is regulated by ecdysone in cultured larval organs and some changes in the temporal patterns of integrin expression correlate with the ecdysone titer profile during metamorphosis. Transcription of alpha- and beta-integrin subunits is also altered in crol and EcR mutants, indicating that integrin expression is dependent upon crol and EcR function. Finally, we describe a new hypomorphic mutation in EcR which indicates that different EcR isoforms can direct the development of adult appendages. This study provides evidence that ecdysone controls wing morphogenesis and cell adhesion by regulating integrin expression during metamorphosis. We also propose that ecdysone modulation of integrin expression might be widely used to control multiple aspects of adult development.

Simultaneous determination of cysteine, cystine and 18 other amino acids in various matrices by high-performance liquid chromatography.

An extraction protocol and a reversed-phase high-performance liquid chromatographic method for the simultaneous determination of cysteine, cystine and 18 other amino acids in biological and vegetable samples are described. Among the different methods proposed for amino acid determination, phenylisothiocyanate was used as the reagent for derivatization. Chromatograms obtained in the analysis of standard solutions and actual samples are reported, together with regression equation, correlation coefficient (> 0.999 for all), limit of detection and recoveries (between 86 and 102% for all the examined matrices) for each amino acid. Practical protocol and method applications in normal patients and patients affected by different pathologies, and in algal products are discussed.

crooked legs encodes a family of zinc finger proteins required for leg morphogenesis and ecdysone-regulated gene expression during Drosophila metamorphosis.

Drosophila imaginal discs undergo extensive pattern formation during larval development, resulting in each cell acquiring a specific adult fate. The final manifestation of this pattern into adult structures is dependent on pulses of the steroid hormone ecdysone during metamorphosis, which trigger disc eversion, elongation and differentiation. We have defined genetic criteria that allow us to screen for ecdysone-inducible regulatory genes that are required for this transformation from patterned disc to adult structure. We describe here the first genetic locus isolated using these criteria: crooked legs (crol). crol mutants die during pupal development with defects in adult head eversion and leg morphogenesis. The crol gene is induced by ecdysone during the onset of metamorphosis and encodes at least three protein isoforms that contain 12-18 C2H2 zinc fingers. Consistent with this sequence motif, crol mutations have stage-specific effects on ecdysone-regulated gene expression. The EcR ecdysone receptor, and the BR-C, E74 and E75 early regulatory genes, are submaximally induced in crol mutants in response to the prepupal ecdysone pulse. These changes in gene activity are consistent with the crol lethal phenotypes and provide a basis for understanding the molecular mechanisms of crol action. The genetic criteria described here provide a new direction for identifying regulators of adult tissue development during insect metamorphosis.

Cross-talking among Drosophila nuclear receptors at the promiscuous response element of the ng-1 and ng-2 intermolt genes.

In Drosophila, peaks of the titer of the steroid hormone ecdysone act as molecular signals that trigger all the major developmental transitions occurring along the life cycle. The EcR/USP heterodimer, known to constitute the functional ecdysone receptor, binds with high affinity to specific target sequences, the ecdysone response elements (EcREs), whose repertoire still remains to be fully characterized at both the molecular and functional levels. In order to investigate the properties of EcREs composed of directly repeated half-sites (DRs), we have analysed the binding properties of the ng-EcRE, a DR element located within the coding region of ng-1 and ng-2, two highly homologous genes mapping at the ecdysone-regulated 3C intermolt puff. We report here that the ng-EcRE contacts the ecdysone receptor through its directly repeated half-sites spaced by 12 bp, and that this element may interact efficiently with at least three Drosophila orphan receptors, namely DHR38, DHR39 and beta FTZ-F1. Interestingly, DHR38 is bound alone or in combination with USP, providing the first evidence that the EcR-USP and DHR38-USP may directly compete for binding to a common response element. These results suggest that EcREs composed of widely spaced DRs may contribute to the establishment of extensive nuclear receptors cross-talking along the development, a mechanism that might play a relevant role in determining the temporal and spatial specificity of the ecdysone response. Finally, we show that the ng-EcRE can promote functional interactions in vitro as well as in vivo, acting as a transcriptional enhancer able to confer a specific developmental expression profile to a minimal promoter in transgenic flies.

A steroid-triggered switch in E74 transcription factor isoforms regulates the timing of secondary-response gene expression.

The steroid hormone 20-hydroxyecdysone (referred to here as ecdysone) directs Drosophila metamorphosis by activating a series of genetic regulatory hierarchies. ETS domain transcription factors encoded by the ecdysone-inducible E74 early gene, E74A and E74B, act at the top of these hierarchies to coordinate the induction of target genes. We have ectopically expressed these E74 isoforms to understand their regulatory functions during the onset of metamorphosis. We show that E74 can regulate its own transcription, most likely through binding sites within its gene. Ectopic expression of E74B can partially repress the E78B and DHR3 orphan receptor genes, suggesting a role for E74 in the appropriate timing of early-late gene expression. Furthermore, E74A is both necessary and sufficient for E78B induction, implicating E74A as a key regulator of E78B expression. We also show, consistent with our studies of E74 loss-of-function mutations, that E74B is a potent repressor of late gene transcription and E74A is sufficient to prematurely induce the L71-1 late gene. However, ectopic expression of both Broad-Complex and E74A activators in an E74B mutant background is not sufficient to prematurely induce all late genes, indicating that other factors contribute to this regulatory circuit. These observations demonstrate that the steroid-triggered switch in E74 transcription factor isoforms plays a central role in the proper timing of secondary-response gene expression.

The moulting hormone ecdysone is able to recognize target elements composed of direct repeats.

In Drosophila melanogaster, three temporally distinct ecdysone-responsive puff sets, the so-called intermoult, early and late puffs, have been described on the salivary gland polytene chromosomes. We have analyzed in detail a DNA segment of the 3C polytene region, from which the originates one of the most prominent intermoult puffs, with the aim of identifying ecdysone response elements (EcREs). Here we report that two putative EcREs of identical sequence are located at this puff site. Interestingly, these elements display a novel structural feature, being composed of directly repeated half-sites. Our results show that the EcR/USP heterodimer known to constitute the ecdysone functional receptor complex is able to bind to and transactivate through target elements composed of directly repeated half-sites. In addition, we show that these elements are also able to bind efficiently USP alone, suggesting that USP and EcR/USP could compete for their binding to DNA.