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This paper comparatively shows the influence of four water treatment processes on the formation of trihalomethanes (THMs) in a water distribution system. The study was performed from February 2005 to January 2012 with analytical data of 600 samples taken in Aljaraque water treatment plant (WTP) and 16 locations along the water distribution system (WDS) in the region of Andévalo and the coast of Huelva (southwest Spain), a region with significant seasonal and population changes. The comparison of results in the four different processes studied indicated a clear link of the treatment process with the formation of THM along the WDS. The most effective treatment process is preozonation and activated carbon filtration (P3), which is also the most stable under summer temperatures. Experiments also show low levels of THMs with the conventional process of preoxidation with potassium permanganate (P4), delaying the chlorination to the end of the WTP; however, this simple and economical treatment process is less effective and less stable than P3. In this study, strong seasonal variations were obtained (increase of THM from winter to summer of 1.17 to 1.85 times) and a strong spatial variation (1.1 to 1.7 times from WTP to end points of WDS) which largely depends on the treatment process applied. There was also a strong correlation between THM levels and water temperature, contact time and pH. On the other hand, it was found that THM formation is not proportional to the applied chlorine dose in the treatment process, but there is a direct relationship with the accumulated dose of chlorine. Finally, predictive models based on multiple linear regressions are proposed for each treatment process. ; The authors wish to express their apprecia- tion to the plant managers GIAHSA (Gestión Integral del Agua de Huelva S.A.) and employees for their help and cooperation in facilitating the collection of water samples during this study. This work was supported by the project CTM2012-38720-C03-01 from the Spanish Ministry of Economy and Competitiveness (MINECO) and by projects P009-FQM-4659 and P12-FQM- 0442 from the Regional Ministry of Economy, Innovation, Sci- ence and Employment (Andalusian Government, Spain). ; The authors wish to express their appreciation to the plant managers GIAHSA (Gestion Integral del Agua de Huelva S.A.) and employees for their help and cooperation in facilitating the collection of water samples during this study. This work was supported by the project CTM2012-38720-C03-01 from the Spanish Ministry of Economy and Competitiveness (MINECO) and by projects P009-FQM-4659 and P12-FQM-0442 from the Regional Ministry of Economy, Innovation, Science and Employment (Andalusian Government, Spain).

Trihalomethanes (THMs) are regulated disinfection by-products (DBPs) most commonly analyzed in quality control water supply due to their harmful effects on health. However, few data exist about the content of emerging iodo-trihalomethanes (I-THMs) which are present in drinking water at very low concentrations (in the order of ng L−1). For this reason a two-phase hollow fiber liquid phase microextraction method for the simultaneous determination of four regulated trihalomethanes and six emerging iodo-trihalomethanes using GC-μECD and GC–MS with detection limits in the range of few ng L−1 has been developed. A central composite design was used to optimize conditions for simultaneous extraction. The best extraction recovery was obtained with 19.2 min at 27.1 °C and 900 rpm, without salt addition, using a supported hollow fiber membrane of 10.5 cm (0.6 mm id) and 1-octanol as acceptor phase. The limits of detection for the regulated THMs and I-THMs were 3–44 ng L−1 and 1–3 ng L−1, respectively. The calibration curves showed good linearity (R2 > 0.995) and good repeatibility (3–22%). The relative recoveries in water were between 96.5% and 105.2%. The method was applied for the simultaneous determination of trihalomethanes in supply water samples from seven water distribution systems (WDS) in the Huelva area, located at the southwest Spain, which use different water-treatment processes. The highest concentrations of I-THMs, particularly CHBrClI and CHCl2I, were detected in water treated with advanced treatment process using pre-ozonation, however these compounds were not detected or decreased along distribution system. In the samples of treated water with conventional treatment, using pre-oxidation by permanganate and distribution network, CHCl2I, CHBrClI, CHClI2, CHBrI2 and CHI3 were detected at very low concentrations (1–18 ng L−1). Finally, in water samples from underground origin without oxidation treatment, in which only disinfection with sodium hypochlorite was applied, I-THMs were not detected. ; The authors wish to express their appreciation to the plant managers GIAHSA and employees for their help and cooperation in facilitating the collection of water samples during this study. This work was supported by the project CTM2012-38720-C03- 01 from the Spanish Ministry of Economy and Competitiveness (MINECO), and by project P012-FQM-0442 from the Regional Min- istry of Economy, Innovation, Science and Employment (Andalusian Government, Spain) ; The authors wish to express their appreciation to the plant managers GIAHSA and employees for their help and cooperation in facilitating the collection of water samples during this study. This work was supported by the project CTM2012-38720-C03-01 from the Spanish Ministry of Economy and Competitiveness (MINECO), and by project P012-FQM-0442 from the Regional Ministry of Economy, Innovation, Science and Employment (Andalusian Government, Spain).

Carcinogenesis is a very complex process in which metals have been found to be critically involved. In this sense, a disturbed redox status and metal dyshomeostasis take place during the onset and progression of cancer, and it is well-known that trace elements participate in the activation or inhibition of enzymatic reactions and metalloproteins, in which they usually participate as cofactors. Until now, the role of metals in cancer have been studied as an effect, establishing that cancer onset and progression affects the disturbance of the natural chemical form of the essential elements in the metabolism. However, it has also been studied as a cause, giving insights related to the high exposure of metals giving a place to the carcinogenic process. On the other hand, the chemical species of the metal or metallobiomolecule is very important, since it finally affects the biological activity or the toxicological potential of the element and their mobility across different biological compartments. Moreover, the importance of metal homeostasis and metals interactions in biology has also been demonstrated, and the ratios between some elements were found to be different in cancer patients; however, the interplay of elements is rarely reported. This review focuses on the critical role of metals in lung cancer, which is one of the most insidious forms of cancer, with special attention to the analytical approaches and pitfalls to extract metals and their species from tissues and biofluids, determining the ratios of metals, obtaining classification profiles, and finally defining the metallome of lung cancer. ; This research was funded by the projects CTM2015-67902-C-1-P from the Spanish Ministry of Economy and Competitiveness, and P12-FQM-0442 from the Regional Ministry of Economy, Innovation, Science and Employment (Andalusian Government, Spain). Projects Neumosur (8/2012 and 9/2015) and SEPAR (124/2012 and 091/2016). Belén Callejón Leblic thanks the Ministry of Education, Culture and Sport for a predoctoral scholarship. Finally, authors are grateful to FEDER (European Community) for financial support, grants number UNHU13-1E-1611 and UNHU15-CE-3140.

Speciation of seleno-metabolites and selenoproteins in Se-enriched Chlorella sorokiniana microalgae, in vitro and in vivo extracts has been performed by HPLC-ICP-MS. Selenium bioaccesibility in Se-enriched Chlorela sorokiniana evaluated by in vitro gastrointestinal digestion of the selenized microalga was 81% (79% as SeMet). Mice supplemeted with Se-enriched C. sorokiniana presented increased Se concentration in kidney, reflecting a potencial mechanism of excretion by urine. In addition, selenium bioavailavility, which was in the range of 3–15% depending on the diet was 1.13-fold higher in mice fed with Se-enriched microalgae against the basal diet, but decreased with higher amounts of selenium. Regarding bioactivity (∑Se as selenoproteins in serum/total Se in serum = 76–85% depending on the diet), selenium and selenoproteins (SeP) increased in serum from animals fed high supplemental Se levels. These results showed that Se-enriched algae can be considered as an alternative selenized food for humans, due to their high Se bioavailability. ; This work has been supported by the projects CTM2015-67902-C2-1-P and PG2018-096608-B-C21 from the Spanish Ministry of Economy and Competitiveness and P12-FQM-0442 and P09-FQM-04659 from the Regional Ministry of Economy, Innovation, Science and Employment (Andalusian Government, Spain). Finally, authors are grateful to FEDER (European Community) for financial support, grants number UNHU13-1E-1611 and UNHU15-CE-3140.