FM22 (Frozen Mitochondria bioassay): an animal alternative bioassay for toxicity measures for water soluble samples.

Several methods have been proposed, using responses of whole organisms. The problem, however, is not only strictly scientific, but also involves cost, resources and time. For example, assay with organisms require expensive testing facilities and long operational times are necessary for toxicity measurements. In order to evaluate potential compound toxicity (acute and sub-chronic), we standardized a bioassay using mitochondria of beef hearth, and their applicability and sensitivity was verified. In respect to other based on mitochondria tests, this bioassay (called FM22) showed unquestionable advantages: i) to freeze mitochondria at -22 °C instead of the classical -80 °C, ii) to perform a very big quantity of biological test using always the same mitochondria pool (avoiding differences from age, sex, or health status depending on different organisms); iii) to identify quickly a tested compounds IC50, easily comparable. FM22 end point is the inhibition of mitochondrial respiratory chain and this event is quantified by oxygen monitoring. The oxygen consumption was measured by a Clark electrode that was interfaced to a PC to collect test analysis data (1200 in 20 Macro, identifiedmin run). A piecewise regression, through an Excel the break point in the oxygen consumption and calculated the toxicity. Blank tests were carried out to verify the oxygen consumption linear fitting. Toxicity tests were performed using pure/mix organic and inorganic compounds, elutriates from sea- and fresh-water sediment, sewage, dissolved burned compound sub-products. The FM22 test was a good predictor of toxicity for water and soluble samples; the bioassay is easy, low cost and rapid, then usable for routine tests or like a part of a battery of ecotoxicological tests

Phytoremediation potential of the arsenic hyperaccumulator Pteris vittata: preliminary results from a field study

Phytoextraction is a promising technique for the remediation of soils contaminated by metals and metalloids and is proposed as a green alternative to conventional remediation methods. This paper reports the preliminary results of a field study carried out to evaluate the potential of the fern Pteris vittata for the phytoremediation of arsenic polluted sites. P. vittata is a known arsenic hyperaccumulator and its properties have been assessed in a number of studies, mainly at laboratory or glasshouse scale, while few field investigations are reported in the literature. The experimental activity was planned to compare and evaluate the effect of different conditions on plant growth and on as uptake by P. vittata. The study area is located in northeastern Italy. During the experimental period, pedoclimatic conditions were shown to affect strongly plant growth as well as As bioaccumulation. The results of two consecutive field trials confirm the phytoextraction ability of P. vittata under field conditions, but indicate also that the optimization of agronomic practices is crucial for the success of a phytoextraction application at fullscale. The inoculation of ferns with arbuscular mycorrhizal (AM) fungi seems to have a positive influence on plant growth, while its role on phytoextraction efficiency still remains unclear

Human migration: the big data perspective

How can big data help to understand the migration phenomenon? In this paper, we try to answer this question through an analysis of various phases of migration, comparing traditional and novel data sources and models at each phase. We concentrate on three phases of migration, at each phase describing the state of the art and recent developments and ideas. The first phase includes the journey, and we study migration flows and stocks, providing examples where big data can have an impact. The second phase discusses the stay, i.e. migrant integration in the destination country. We explore various data sets and models that can be used to quantify and understand migrant integration, with the final aim of providing the basis for the construction of a novel multi-level integration index. The last phase is related to the effects of migration on the source countries and the return of migrants

Was it Uruguay or Coffee? The causes of the beef jerky industry’s decline in southern Brazil (1850 – 1889)

What caused the decline of the beef jerky’s production in Brazil? The main sustenance for slaves, beef jerky was the most important industry in southern Brazil. Nevertheless, by 1850, producers were already worried that they could not compete with Uruguayan industry. Traditional interpretations impute the decline to labor markets differences in productivity, since Brazil used slaves while Uruguay had abolished slavery in 1842. Recent research also raises the possibility of a Brazilian “Dutch Disease”, resulting from the coffee exports boom. We test both hypothesis and argue that Brazilian production’s decline was associated with structural changes in demand for low quality meat. Trade protection policies created disincentives for Brazilian producers to increase productivity and diversify its cattle industry

FM22 (Frozen Mitochondria bioassay) as potential tool for inhalation exposure toxicity measures.

A wide variety of fire combustion substances can be produced during a fire, comprising of gases, organic vapours and particulate matter. From them, a wide kind of toxicological outputs may derive and the following toxicity during a fire event is characterized by a large number of additive, synergistic and antagonistic toxicological interactions into organisms. So, close to a chemical analysis of a burned compound it should be better support the knowledge with a bioassay approach. Aim of this work was to monitor whether FM22 bioassay may be a good test in order to find a reliable way of evaluating possible combined effects from burned anthropogenic substances. Then, 1,2-dichloroethane, acrylonitrile, EVC pitch, tetraline, toluene, Montefibre mix have been tested and mitochondrial respiration inhibition was performed as bioassay end point. LC50 has been determined and matched with TEEL (Temporary Emergency Exposure Limit) values applied on GC-MS chromatogram analysis results of combusted substances. A very interesting phenomena, i.e. hormetic response, has been also registered with FM22 bioassay application

Halophytes for Phytoremediation of Lead in a Salt Marsh in the Venice Lagoon

A small but important area on the Venice lagoon was used as a shooting range for more than thirty years. As a result of this activity, this sensitive salt marsh area is now dangerously contaminated by Pb, Cu, Sb and As. This extremely dynamic and complex ecosystem can promote the accumulation of metals and metalloids in both soil and sediment, and favours their conversion into more reactive compounds by physicochemical and biochemical transformations. Changes in redox and pH conditions can promote the mobility of these metals/metalloids, thus increasing their potential bioavailability. The characterization of contamination in this area pointed out a markedly variable Pb concentration (100-6700 mg Kg-1 dw), while Cu (about 60 mg Kg-1 dw) and metalloids (As and Sb < 20 mg Kg-1 dw) showed homogeneous distributions. As, Cu and Sb concentrations were below regulatory limits (they do not represent a serious risk), while Pb concentration was above the established limit. Geochemical speciation showed that a high percentage of total Pb content can be potentially mobilized and become thus phytoavailable in the particular conditions of this ecosystem. In the salt marsh the most abundant plant species are Limonium vulgaris, Salicornia, Spartina and Puccinellia). Preliminary analysis for Pb accumulation showed that all these plants have a low translocation factor (TF); nonetheless Limonium and Salicornia showed a bioaccumulation factor (BAF) in the roots greater than one. These results point out the possibility of using natural chelating agents to improve uptake and translocation efficiency of Pb in these plant

FM22 (Frozen Mitochondria bioassay) quale potenziale test per la valutazione di esposizione per inalazione.

Il problema delle sostanze che si producono durante un incendio è estremamente sentito sia dal personale adibito per ragioni professionali all’intervento di limitazione e gestione dell’evento, sia dalla popolazione ubicata nelle immediate vicinanze al focolaio. Durante un incendio si può produrre una grandissima varietà di composti, compresi gas, vapori organici e materiale particolato. Da questi in toto si può generare una enorme gamma di effetti tossicologici negli organismi. Tali effetti sono difficilmente discernibili in quanto ad agente scatenante, essendo il risultato finale di processi sinergici/antagonisti/additivi dipendenti (a parità di tipo e quantità di sostanze combuste) da una parte dalle modalità di sviluppo dell’incendio stesso, dall’altra dal tipo di esposizione su un determinato organismo. Scopo di questo studio è stato quello di verificare se il test denominato FM22 (Frozen Mitochondria at -22°C bioassay, test di inibizione della respirazione mitocondriale) possa essere annoverato quale bioassay di primo approccio per la valutazione della tossicità di miscele derivate da combustione, in condizioni controllate, di sostanze pure e/o mix, di origine antropica. L’ipotesi di partenza sta nella considerazione che, in virtù della fisiologia stessa che governa lo scambio dei gas respiratori, nonché per l’elevata temperatura dei fumi inalabili durante un incendio, ciò che arriva a livello dei bronchioli polmonari riesce facilmente ad entrare e, pertanto, ad avere una potenziale azione tossica direttamente a livello mitocondriale. I prodotti di combustione testati con FM22 sono stati ovviamente anche analizzati al GC-MS, operando, quando possibile, una identificazione e una quantificazione delle centinaia di picchi risultanti nei cromatogrammi. Oltre a ciò, si è tentato una elaborazione con i TEEL (Temporary Emergency Exposure Limit) cercando di correlare tale approccio con i risultati (espressi come IC50) dopo applicazione del FM22 bioassay

Analisi comparativa del contenuto di elementi maggiori e in traccia nelle conchiglie di due specie di Bivalvi della Laguna di Venezia.

E’ noto che i Bivalvi sono organismi filtratori e, in quanto tali, efficienti accumulatori di contaminanti e ideali organismi indicatori: per questo sono ampiamente utilizzati nei programmi di biomonitoraggio per valutare i livelli di inquinanti in ambienti marini e di transizione. Nella maggior parte dei casi gli esperimenti sono condotti per valutare i livelli di concentrazione nei tessuti molli: in questo caso si vuole focalizzare l’attenzione sulla composizione delle valve, nell'ottica di una comprensione più approfondita dei meccanismi che controllano il trasferimento di contaminanti inorganici nelle parti carbonatiche dell’organismo. In particolare si opera un confronto tra due specie diverse di Bivalvi, Crassostrea gigas e Mytilus galloprovincialis, prelevate dagli stessi siti di campionamento posizionati nell’area urbana della città di Venezia (Arsenale Vecchio). Queste condizioni permettono di valutare la misura in cui le caratteristiche fisiologiche della specie influenzano gli equilibri e i percorsi metabolici dei singoli elementi nell'organismo. Le concentrazioni degli elementi maggiori e di quelli in traccia sono state determinate analiticamente nei tessuti molli e nelle valve: ciò ha permesso di evidenziare il partizionamento degli elementi tra le due matrici. Si ritiene che la capacità da parte di una specie di accumulare preferenzialmente determinati elementi nella conchiglia possa essere utile per valorizzare il ruolo dei Bivalvi nei meccanismi di auto-purificazione dei bacini d’acqua, nella prospettiva di un loro possibile utilizzo in future applicazioni