1,720,983 research outputs found
Indexes of tobacco smoke contribution to environmental particulates based on molecular fingerprints of alkanes - Indici del contributo del fumo di tabacco ai particolati ambientali basati sull’impronta molecolare degli alcani
No full textIl fumo di tabacco (TS) è la sorgente di molte specie tossiche che contaminano in modo ubiquitario
l’aria e impattano sulla salute anche dei non fumatori. In ragione di ciò le proprietà chimiche, fisiche e
tossicologiche degli esausti (sia i vapori, sia i fumi direttamente aspirati, dispersi nell’intorno e
nell’intero ambiente) sono stati estesamente studiati. Oltre a una manciata di macro-componenti della
combustione (CO, catrame, polveri fini e ultrafini, NO, NO2), nei fumi sono state identificati moltissimi
micro-componenti organici. Alcuni di questi, come specie individuali o gruppi, si presentano come
“impronte molecolari” sufficientemente tipiche per fungere da potenziali marker chimici del TS.
Tuttavia, se si eccettua la nicotellina [1] tuttora non è stato definito alcun indice adatto a produrre
(semi)quantitative stime del contributo del TS all’inquinamento ambientale, p.es. la percentuale del
TS presente nelle polveri sospese atmosferiche e nelle deposizioni, in termini di massa totale o della
sua componente organica. Tra i costituenti del TS, gli alcani lineari (normali) a catena lunga (C29-C34) e
i corrispondenti isomeri iso- e anteiso- presentano peculiari distribuzioni percentuali e impronte
molecolari[2]. Inoltre, grazie alla loro scarsa volatilità e buona persistenza in aria, la determinazione di
questi composti è meno soggetta ad artifact rispetto ai nicotinoidi e ai vapori organici. Il presente
contributo descrive i risultati di una ampia indagine condotta sulla frazione lipidica non polare di
polveri sospese e di deposizione raccolte in ambienti indoor e outdoor. Tra i parametri potenzialmente
atti a descrivere la distribuzione degli alcani C29-C34 nel TS, ne sono stati scelti i tre più promettenti e
attraverso la media dei loro valori è stato definito un indice cumulativo (TSI%) per la stima della
percentuale del TS presente nelle polveri. Inoltre, l’eccesso di n-C31 rispetto alla media di n-C29 e n-C33,
anch’esso tipico del TS, è stato identificato come ulteriore indice; la correlazione tra i due indici
risultava significativa nel caso delle polveri sospese (soprattutto indoor), ma non per le deposizioni. In
base alla composizione delle serie di campioni ambientali analizzate, il TS risultava contaminare anche
aree rurali. Nelle abitazioni di non fumatori il TS costituiva fino al 2.1% della massa totale delle polveri
sospese carboniose e fino allo 0.43% delle deposizioni. Il TSI% risulta adatto alla stima del contributo
del fumo di tabacco alle polveri in ambienti interni preclusi al fumo e all’aria esterna, mentre in locali
altamente inquinati (stanze per fumatori) altri marker molecolari (p.es. la nicotina e la cotinina) sono
presumibilmente più attendibili.
[1] N.J. Aquilina, C.M. Havel, P. Cheung, R.M. Harrison, K.F. Ho, N.L. Benowitz, P. Jacob III, Environ. Int.,
2021, 150, 106417. DOI: 10.1016/j.envint.2021.106417.
[2] I.G. Kavouras, N. Stratigakis, E.G. Stephanou, Environ. Sci. Technol., 1998, 32, 1369-1377. DOI:
2481/10.1021/es970634eTobacco smoking is the source of a number of toxicants globally affecting the air and posing a concern
also for no smokers. Hence, chemical, physical and toxicological features of exhausts (i.e., vapours as
well as mainstream, sidestream and third hand smoke) have been extensively investigated. Apart from
a handful of macro-components of combustion (e.g., CO, tar, fine and ultrafine particles, nitrogen
oxides), some hundreds of organic substances have been identified in smoke. Some of these chemicals,
individually or as groups, give raise to peculiar molecular fingerprints and look potentially suitable to
act as “chemical signature” of tobacco smoke (TS). Nevertheless, except for nicotelline [1] no indexes
have been identified until now as suitable to draw (semi)quantitative estimates of the contribution of
TS to environmental pollution, e.g. the TS percentage in particulate matters (carbonaceous aerosol
and settled dust), nor in the respective organic fractions. Among TS costituents, long-chain normal-,
iso- and anteiso- alkanes (C29-C34) show special percent distributions and molecular signatures [2].
Besides, thanks to low volatility and high persistence in the atmosphere, the evaluation of these
chemicals is less prone to artifacts than nicotinoids and organic vapours. This contribution describes
the results of an extensive investigation conducted on non-polar lipid fraction of particulates collected
in interiors and outdoors. Among various potential parameters associated to long-chain alkane
fingerprints, the three most promising ones were selected and finally a cumulative index (TSI) was
defined through averaging them, suitable to estimate the TS percentage in organic particulates.
Besides, the exceedance of normal C31 alkane with respect to average of n-C29 and n-C33 homologues
was identified as a further index, and the two indexes were plotted vs. each other, revealing a link in
the case of airborne particulates but not of dusts. According to back analysis carried out on several
sets of particulates, TS seemed to affect even rural areas, while inside non smokers’ homes the
contributions of TS to PM could account for up to ca. 2.1% and 0.43%, respectively, in airborne
particulates and dusts. The TSI% index seemed to run well in interiors forbidden to smoking and at
open air, whereas other molecular markers, e.g. nicotine and cotinine, are expected to work better in
very polluted locations (e.g. smoking rooms).
[1] N.J. Aquilina, C.M. Havel, P. Cheung, R.M. Harrison, K.F. Ho, N.L. Benowitz, P. Jacob III, Environ. Int.,
2021, 150, 106417. DOI: 10.1016/j.envint.2021.106417.
[2] I.G. Kavouras, N. Stratigakis, E.G. Stephanou, Environ. Sci. Technol., 1998, 32, 1369-1377.
DOI: 2481/10.1021/es97063
Thermal stability and decomposition mechanism of 1-allylimidazole coordination compounds: a TG-FTIR study of Co(II), Ni(II) and Cu(II) hexacoordinate complexes
No full textA thermoanalytical study of 1-allylimidazole complexes with divalent transition metal ions, such as Co(II), Ni(II) and Cu(II) is reported. The precipitated [ML(6)](NO(3))(2) Octahedral compounds were characterized by elemental analysis and thermo-gravimetry (TG)-FTIR spectroscopy
Determination of fragrances in interiors
No full textFragrances and essences (F&Es) have nowadays ascertained as contaminants of interiors, due to the
wide presence of these chemicals in personal care and house product formulas [1, 2]. Indeed, their
occurrence has been demonstrated in the air of homes and cars as well as of public premises like
schools, universities and hospitals. Despite their worldwide use, fragrances belong to the class of
emerging organic contaminants, also known as endocrine disruptors. In fact, though F&Es do not
seem to display carcinogenic properties, however they can give raise to long- and short-term health
problems, e.g. inflammation of skin, eyes and throat, allergies, and even heart, metabolism and brain
difficulties as well as gene damaging [3, 4]. Most F&Es are semi-volatile and exist overall as vapours,
nonetheless they have been observed also in airborne particulates (PM10, PM2.5) and in deposition
dusts of interiors; that worsens the exposure of humans to these chemicals, because it is not restricted
to inhalation but depends also on ingestion and contact paths. On the other hand, that makes necessary
to collect both gas and particle fractions to draw information about the impact of F&E in indoor
environment; that can be achieved by using filter-cartridge trains able to retain quantitatively the
targeted compounds. As for analytical procedures, usually they consist of solvent extraction/thermosdesorption coupled with GC-MS detection.
A dedicated procedure was optimized to determine the concentrations of F&Es in the interiors.
Airborne particles (PM2.5) were collected on PTFE membranes, while the gas fraction was retained
on XAD-2 cartridges. The analytes were recovered from XAD-2 through elution with acetone, and
from filters through extraction in ultrasonic bath; after solvent reduction, F&Es were determined
through GC-MSD operated in SIM mode. The recovery efficiency, LoD and LoQ values were
evaluated. The procedure was applied to a set of samples collected in two locations, which confirmed
the occurrence of F&Es in the interiors as well as outdoors.
[1] J. P. Lamas, L. Sanchez-Prado, C. Garcia-Jares, M. Llompart, J. Chromatog. A, 2010, 1217,
1882–1890.
[2] M. Fontal, B. L. van Drooge, J. O. Grimalt, J. Chromatog. A, 2016, 1447, 135–140
[3] E. Uhde, N. Schulz, Atmos. Environ., 2015, 106, 492-502
[4] P. Wolkoff, G. D. Nielsen, Environ. Int., 2017, 101, 96–107
Chimica, Chimici ed Etica Ambientale: un connubio possibile
No full textIl nostro tempo è caratterizzato da una forte polarizzazione dell’atteggiamento individuale e sociale nei confronti dell’inquinamento in tutte le sue forme e, di converso, riguardo alla tutela sanitaria e ambientale. Da una parte ci sono i “negazionisti”, che confidano in una qualche “autotutela” del sistema-Terra per tamponare gli effetti disastrosi delle trasformazioni chimiche, biologiche e fisiche imposte dall’uomo al mondo che lo circonda, oppure darwinisticamente scaricano il problema sui posteri e sulle popolazioni e classi che non hanno accesso alle nuove tecnologie. Dall’altra, gli “ecologisti d’assalto duri e puri”, predicano un “ritorno alla natura” e il “regresso felice” senza peraltro rinunciare a molta della tecnologia che aborriscono. Sono voci forti, che rappresentano percentuali infinitesime della società ma ne condizionano pesantemente la vita attraverso il potere dei mercati, della politica e dei mass media: basti pensare a Trump e ai Gruppi Verdi con venature eco-terroristiche. La stragrande parte dei cittadini sembra poco coinvolta, per un deficit d’informazione corretta e completa.
Alla Chimica e alla categoria dei chimici, si attribuisce una grande parte dell’inquinamento ambientale: mari interdetti alla balneazione e fiumi maleodoranti schiumosi, terreni “bruciati” alle coltivazioni e all’allevamento, cieli con le fantomatiche “scie chimiche”, falde acquifere imbevibili, aria che puzza e fa venire i tumori... dietro tutto ciò si cerca e si trova quasi sempre un chimico che ha inventato e messo sul mercato sostanze dannose. Purtroppo ciò è quasi sempre vero, anche se i chimici sono in buona compagnia di politici, industriali, agricoltori, ma anche turisti, consumatori...
Come se ne esce? Non sembra sufficiente operare sulla difensiva, ma è impellente una presa di coscienza e assunzione di responsabilità a livello sociale: operare nel rispetto della creazione (o, per chi non crede, del mondo di cui siamo parte) ponendosi al servizio del bene comune; farsi attori di una (in)formazione seria, oggettiva, senza reticenze né cadute di stile; non prescindere dai contributi delle altre scienze, sia naturali che umane (filosofi, teologia, etica, sociologia...).
Riporto qui un esempio: l’opinione pubblica è spesso orientata (manipolata) verso temi ambientali di scarsa valenza, almeno oggi e in termini globali (pensiamo alle diossine, al particolato diesel), mentre non è affatto informata dei rischi connessi alla presenza e all’uso quotidiano di numerosissimi prodotti e sostanze dannosi (plastificanti, detergenti, sanificanti, pesticidi, ignifughi; si dà importanza all’inquinamento esterno e si tace su quello degli ambienti interni, dove pure trascorriamo almeno l’80% della vita: in Italia manca persino una legislazione specifica per l’inquinamento indoor. Se individualmente si può fare e incidere poco, unendo le voci e le forze, anche attraverso Organi che già sono presenti nella comunità scientifica e dislocati sul territorio (Università, Istituti CNR, Centri di Ricerca, ISS, Ministeri della Salute e dell’Ambiente...) si può fare massa critica sufficiente ad incidere sulla società e la politica.
La comunicazione vuol proporre uno stimolo alla riflessione personale e, eventualmente, alla condivisione di opinioni ed esperienze
Indicatori d’impatto delle emissioni naturali e antropiche nelle polveri
No full textBibliografia
[1] Alves CA et al., 2000. Environ. Sci. Technol. 34, 4287-4293
Indexes of tobacco smoke contribution to environmental particulates based on molecular fingerprints of alkanes.
No full textTobacco smoke (TS) is the source of a number of toxicants affecting the atmosphere
and poses a threat to smokers and the whole community. Chemical, physical and
toxicological features of smoking products (vapours as well as mainstream, side
stream and third hand smoke) have been investigated extensively. Special attention is
paid to organic compounds (individually or in combination giving raise to peculiar
molecular fingerprints), potentially able to act as “chemical signature” of TS. At this
regard, the percent distribution of long-chain normal , iso and anteiso alkanes was
ascertained as typical of TS. Nevertheless, until now no indexes have been identified
as suitable for assessing the global TS contribution to environmental pollution, e.g. the
TS percentage in carbonaceous aerosol and in deposited dusts, the only exception
consisting in the use of nicotelline as tracer. This paper describes the results of an
extensive study aimed at chemically characterizing the non-polar lipid fraction
associated to suspended particulates (PMs) and deposition dusts (DDs) collected at
indoor and outdoor locations. Based on the iso , anteiso and normal C 29 -C 34
alkane profile in the samples as well in tobacco smoke and no-TS related emissions
(literature data), various parameters describing the distribution of compounds were
investigated. Finally, a cumulative variable was identified as tobacco smoke impact
index (TS%) suitable for estimating the TS percentage occurring in the particulate
matter. The TS% rates were plotted vs. the exceedance of normal C 31 alkane with
respect to average of C 29 and C 33 homologues, which results higher in TS than in
most other emissions, revealing a link in the case of suspended particulates but not of
deposited dusts. According to back analysis carried out on all particulate matter sets, it
was found that traces of TS affect even remote areas, while inside the smokers’ homes
the contributions of TS to PM could account for up to ~61% and ~10%, respectively, in
PM and DD. This confirms the need of valuing the health risk posed by TS to humans,
by means of tools ease to apply in extensive investigations
Indexes of tobacco smoke contribution to environmental particulates based on molecular fingerprints of alkanes
No full textTobacco smoke (TS) is the source of a number of toxicants affecting the atmosphere and poses a threat to smokers and the whole
community. Chemical, physical, and toxicological features of smoking products (vapors as well as mainstream, side stream, and
third-hand smoke) have been investigated extensively. Special attention is paid to organic compounds (individually or in
combination giving rise to peculiar molecular fingerprints), potentially able to act as “chemical signature” of TS. In this regard,
the percent distribution of long-chainnormal, iso, and anteiso alkanes was ascertained as typical of TS. Nevertheless, until now
no indexes have been identified as suitable for assessing the global TS contribution to environmental pollution, e.g., the TS
percentage in carbonaceous aerosol and in deposited dusts, the only exception consisting in the use of nicotelline as tracer. This
paper describes the results of an extensive study aimed at chemically characterizing the nonpolar lipid fraction associated to
suspended particulates (PMs) and deposition dusts (DDs) collected at indoor and outdoor locations. Based on the iso, anteiso, and
normal C29–C34 alkane profile in the samples as well in tobacco smoke- and no-TS-related emissions (literature data), various
parameters describing the distribution of compounds were investigated. Finally, a cumulative variable was identified as the
tobacco smoke impact index (TS%) suitable for estimating the TS percentage occurring in the particulate matter. The TS% rates
were plotted vs. the exceedance of normal C31 alkane with respect to the average of C29 and C33 homologs, which results higher
in TS than in most other emissions, revealing a link in the case of suspended particulates but not of deposited dusts. According to
back analysis carried out on all particulate matter sets, it was found that traces of TS affect even remote areas, while inside the
smokers’ homes the contributions of TS to PM could account for up to ~61% and ~10%, respectively, in PM and DD. This
confirms the need of valuing the health risk posed by TS to humans, by means of tools easy to apply in extensive investigations
Psychotropic substances in hospital interiors
No full textTechnical literature concerning the
Psychotropic Substances (PSs) in air
remains very scarce and investigations have been conducted overall in Italy,
both outdoors and indoors. Nine different locations were investigated inside the
public hospital, and three locations in the clinic.
All locations resulted contaminated by illicit PSs, at level of
few μg/g of dust.
Nicotine also was occurring in all locations, despite smoking
is forbidden in interiors
EMERGING ORGANIC CONTAMINANTS IN INTERIORS
No full textRecently, emerging contaminants (ECs) have gained the concern of environmental scientists. This class of toxicants is overall typical of indoor environments; aside of work places, interiors of dwellings, public buildings, offices and shopping centers are involved; there, people spend most of the life time (80-90% of the total). In interiors, ECs reach concentrations much higher than outdoors, giving raise to exposure rates up to thousands times higher. Even the way of toxicants’ intake changes; indeed, while at open air inhalation is predominant, indoors both ingestion and contact gain importance.
ECs display a wide variety of chemical properties and toxicity forms. Most EDs are organic displaying semi-volatile properties, occur in a number of healthcare and house products, in foods, furniture and building materials; usually EDs are not carcinogenic but promote allergies, immune depression, irritation and other acute effects, endocrine system damages, as well as chronic diseases like diabetes, infertility and psychologic problems. Among ECs, key roles are played by plasticizers (e.g., phthalates and adipates), flame retardants (PBDEs, organic phosphates),. Worth of note, EC chemicals occurring in ambient air and surfaces are distinct from those affecting waters (fluorinated surfactants, alkyl ethoxylates, drug by-products).
No attention is usually paid to psychotropic compounds (with illicit drugs) as well as to pharmaceuticals, analogously to cosmetics whose formulas include a list of anti-oxidants/UV light shields and additives (parabens, alkylphenols, bisphenols; fragrances and siloxanes) ascertained as harmful. Interestingly, these categories affect air in the native form, unlike waters, sewages and wastes, where they occur overall as degradation products [1]. Almost no investigations have been conducted till now and cumulative data bases are poor.
To improve the knowledge at this regards, an extensive study has been undertaken in Italy aimed at identifying a list of target substances (crossing toxic properties and environmental occurrence of ECs, with special focus on drugs and pharmaceuticals), at optimizing the sampling and chemical analysis procedures for both gaseous and particulate chemicals based on bench-top GC-MSD techniques), and at acquiring information about their loads and behaviours in interiors, through in-field measurements conducted at schools, dwellings, offices, labs and hospitals.
References
[1] A. Cecinato, P. Romagnoli, M. Perilli, C. Balducci. Environ. Sci. Pollut. Res., 2017, 35, 21256.
Characterization of organic fraction associated to dust of Salerno University interiors
No full textAs hosting students, teachers and researchers and, contemporarily, being sites whose activities often require using chemicals that pose a threat, university premises look important subjects of investigation with regards to interiors’ pollution. Despite that, insufficient measurements have been performed until now. Scarce information is still available about the occurrence of organic toxicants, in particular of emerging organic contaminants, whose characterization would allow estimating the relative impact of internal and external sources of health risk. Though health risk has been associated overall to inhalation of toxicants (and therefore to vapours and fine aerosols), nevertheless in interiors contact and ingestion are important. Thus, also dusts settled on surfaces contribute to loss of environmental quality.
The characterization of organic compounds associated to settled dusts was performed at two locations (the bar hall and library) of University of Salerno, in the Department of Pharmacy. Contemporarily, dust was collected outdoors.
The surfaces (flat, each 0.40 m2, situated 1.5-2.0 m over the ground) were cleaned with pre-washed towels and exposed to air over 30 days; afterwards, settled dusts were collected through wiping accurately with glass wool strips previously baked in oven at 250°C.
Dust samples were extracted in ultrasonic bath and fractionated through column chromatography on neutral alumina. Instrumental analyses were carried out in GC-MSD and were focused on n-alkanes, PAHs, phthalates, psychotropic substances and a list of emerging contaminants including parabens, nonylphenol and bisphenol-A.
All contaminants were more abundant indoors than outdoor by a factor ranging from ~2 to >100. This seems to indicate that indoors sources were more important that chemical intrusion from outdoors, and/or the lifetime of targeted compounds was longer indoors
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