Examinando por Autor "Pizarro, Jaime"

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    Black carbon and other light-absorbing impurities in snow in the Chilean Andes
    (Nature Publishing Group, 2019-12) Rowe, Penny M.; Cordero, Raul R.; Warren, Stephen G.; Stewart, Emily; Doherty, Sarah J.; Pankow, Alec; Schrempf, Michael; Casassa, Gino; Carrasco, Jorge; Pizarro, Jaime; MacDonell, Shelley; Damiani, Alessandro; Lambert, Fabrice; Rondanelli, Roberto; Huneeus, Nicolas; Fernandoy, Francisco; Neshyba, Steven
    Vertical profiles of black carbon (BC) and other light-absorbing impurities were measured in seasonal snow and permanent snowfields in the Chilean Andes during Austral winters 2015 and 2016, at 22 sites between latitudes 18°S and 41°S. The samples were analyzed for spectrally-resolved visible light absorption. For surface snow, the average mass mixing ratio of BC was 15 ng/g in northern Chile (18–33°S), 28 ng/g near Santiago (a major city near latitude 33°S, where urban pollution plays a significant role), and 13 ng/g in southern Chile (33–41°S). The regional average vertically-integrated loading of BC was 207 µg/m 2 in the north, 780 µg/m 2 near Santiago, and 2500 µg/m 2 in the south, where the snow season was longer and the snow was deeper. For samples collected at locations where there had been no new snowfall for a week or more, the BC concentration in surface snow was high (~10–100 ng/g) and the sub-surface snow was comparatively clean, indicating the dominance of dry deposition of BC. Mean albedo reductions due to light-absorbing impurities were 0.0150, 0.0160, and 0.0077 for snow grain radii of 100 µm for northern Chile, the region near Santiago, and southern Chile; respective mean radiative forcings for the winter months were 2.8, 1.4, and 0.6 W/m 2 . In northern Chile, our measurements indicate that light-absorption by impurities in snow was dominated by dust rather than BC. © 2019, The Author(s).
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    Elemental and Mineralogical Composition of the Western Andean Snow (18°S–41°S)
    (Nature Publishing Group, 2019-12) Alfonso, Juan A.; Cordero, Raul R.; Rowe, Penny M.; Neshyba, Steven; Casassa, Gino; Carrasco, Jorge; MacDonell, Shelley; Lambert, Fabrice; Pizarro, Jaime; Fernandoy, Francisco; Feron, Sarah; Damiani, Alessandro; Llanillo, Pedro; Sepulveda, Edgardo; Jorquera, Jose; Garcia, Belkis; Carrera, Juan M.; Oyola, Pedro; Kang, Choong-Min
    The snowpack is an important source of water for many Andean communities. Because of its importance, elemental and mineralogical composition analysis of the Andean snow is a worthwhile effort. In this study, we conducted a chemical composition analysis (major and trace elements, mineralogy, and chemical enrichment) of surface snow sampled at 21 sites across a transect of about 2,500 km in the Chilean Andes (18–41°S). Our results enabled us to identify five depositional environments: (i) sites 1–3 (in the Atacama Desert, 18–26°S) with relatively high concentrations of metals, high abundance of quartz and low presence of arsenates, (ii) sites 4–8 (in northern Chile, 29–32°S) with relatively high abundance of quartz and low presence of metals and arsenates, (iii) sites 9–12 (in central Chile, 33–35°S) with anthropogenic enrichment of metals, relatively high values of quartz and low abundance of arsenates, (iv) sites 13–14 (also in central Chile, 35–37°S) with relatively high values of quartz and low presence of metals and arsenates, and v) sites 15–21 (in southern Chile, 37–41°S) with relatively high abundance of arsenates and low presence of metals and quartz. We found significant anthropogenic enrichment at sites close to Santiago (a major city of 6 million inhabitants) and in the Atacama Desert (that hosts several major copper mines). © 2019, The Author(s).
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    Ítem
    Pharmaceutical pollution of the world's rivers
    (National Academy of Sciences, 2022-02-22) Wilkinson, John L.; Boxall, Alistair B.A.; Kolpin, Dana W.; Leung, Kenneth M.Y.; Lai, Racliffe W.S.; Galban-Malag, Cristobal; Adell, Aiko D.; Mondon, Julie; Metian, Marc; Marchant, Robert A.; Bouzas-Monroy, Alejandra; Cuni-Sanchez, Aida; Coors, Anja; Carriquiriborde, Pedro; Rojo, Macarena; Gordon, Chris; Cara, Magdalena; Moermond, Monique; Luarte, Thais; Petrosyan, Vahagn; Perikhanyan, Yekaterina; Mahon, Clare S.; McGurk, Christopher J.; Hofmann, Thilo; Kormoker, Tapos; Iniguez, Volga; Guzman-Otazo, Jessica; Tavares, Jean L.; Figueiredo, Francisco Gildasio; Razzolini, Maria T.P.; Dougnon, Victorien; Gbaguidi, Gildas; Traore, Oumar; Blais, Jules M.; Kimpe, Linda E.; Wong, Michelle; Wong, Donald; Ntchantcho, Romaric; Pizarro, Jaime; Ying, Guang-Guo; Chen, Chang-Er; Paez, Martha; Martınez-Lara, Jina; Otamonga, Jean-Paul; Pote, John; Ifo, Suspense A.; Wilson, Penelope; Echeverrıa-Saenz, Silvia; Udikovic-Kolic, Nikolina; Milakovic, Milena; Fatta-Kassinos, Despo; Ioannou-Ttofa, Lida; Belusova, Vladimıra; Vymazal, Jan; Cardenas-Bustamante, Marıa; Kassa, Bayable A.; Garric, Jeanne; Chaumot, Arnaud; Gibba, Peter; Kunchulia, Ilia
    Environmental exposure to active pharmaceutical ingredients (APIs) can have negative effects on the health of ecosystems and humans. While numerous studies have monitored APIs in rivers, these employ different analytical methods, measure different APIs, and have ignored many of the countries of the world. This makes it difficult to quantify the scale of the problem from a global perspective. Furthermore, comparison of the existing data, generated for different studies/regions/continents, is challenging due to the vast differences between the analytical methodologies employed. Here, we present a global-scale study of API pollution in 258 of the world's rivers, representing the environmental influence of 471.4 million people across 137 geographic regions. Samples were obtained from 1,052 locations in 104 countries (representing all continents and 36 countries not previously studied for API contamination) and analyzed for 61 APIs. Highest cumulative API concentrations were observed in sub-Saharan Africa, south Asia, and South America. The most contaminated sites were in low- to middle-income countries and were associated with areas with poor wastewater and waste management infrastructure and pharmaceutical manufacturing. The most frequently detected APIs were carbamazepine, metformin, and caffeine (a compound also arising from lifestyle use), which were detected at over half of the sites monitored. Concentrations of at least one API at 25.7% of the sampling sites were greater than concentrations considered safe for aquatic organisms, or which are of concern in terms of selection for antimicrobial resistance. Therefore, pharmaceutical pollution poses a global threat to environmental and human health, as well as to delivery of the United Nations Sustainable Development Goals.