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Organic contaminants in sediments from San Quintin Bay, Baja California, Mexico.
1996
Galindo E.A.G. | Celaya J.A.V. | Munoz G.F. | Sericano J.L.
(Methyl) Mercury, arsenic, and lead contamination of the world's largest wastewater irrigation system : the Mezquital Valley (Hidalgo State-Mexico)
2014
Guédron, Stéphane | Duwig, Celine | Prado, B. L. | Point, David | Flores, M. G. | Siebe, C. | Institut des Sciences de la Terre (ISTerre) ; Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS) | Laboratoire d'étude des transferts en hydrologie et environnement (LTHE) ; Observatoire des Sciences de l'Univers de Grenoble (OSUG) ; Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS) | Géosciences Environnement Toulouse (GET) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)
In the Mezquital valley, untreated wastewater (45 m(3) s(-1)) from Mexico City is used for the irrigation of around 900 km(2) of agricultural soil. High concentrations of metals including methylmercury (3.8+/-2.5 ng l(-1)) and lead (0.16+/-0.05 mg l(-1)) were measured in anoxic wastewater canals. Downstream, dissolved, and particulate polymetallic (Hg, Pb, Cr.) concentrations decreased by factors 10 to 1,000 in the Tula River (which received a mix of fresh and wastewater) due to the dilution and oxidation of surface water, and to the decrease of contaminants concentration in wastewater downstream irrigated soils. However, dissolved and particulate methylmercury concentrations (0.06 to 0.33 ng l(-1) and 1.6 to 4.5 g kg(-1), respectively) remained elevated in comparison to other natural hydrosystems. The monitoring of an irrigation event and the distribution of metals in a soil profile irrigated for more than 80 years showed that metals were retained in the draining tilled layer. The oxic conditions and slightly acidic pH (similar to 6.5) in this layer were found favorable for metal adsorption and co-precipitation with redox-sensitive elements (Fe, Mn) and suggestively for mercury demethylation. In the downstream Tula River and groundwater, almost all metallic concentrations remained below guideline thresholds. Only, dissolved As and Pb concentrations remained two to five times above thresholds for drinking water, highlighting a potential health risk for approximately 500,000 people who use groundwater as water supply.
Afficher plus [+] Moins [-]Observations of ozone-induced foliar injury on black cherry (Prunus serotina, var. capuli) within the Desierto de Los Leones National Park, Mexico City
1997
Skelly, J.M. | Savage, J.E. | Bauer, M. de L. de | Alvarado, D. (Department of Plant Pathology, Pennsylvania State University, University Park, PA 16802 (USA))
Distribution, origin and fate of chromium in soils in Guanajuato, Mexico
1996
Armienta, M.A. | Rodriguez, R. | Ceniceros, N. | Juarez, F. | Cruz, O. (Instituto de Geofisica, UNAM, Circuito Exterior, CU Mexico, 04510 DF (Mexico))
Effects of oxidant air pollution on Pinus maximartinezii Rzedowski in the Mexico City region
1996
Hernandez Tjeda, T. | Nieta de Pascual Pola, C. (Centro Nacional de Investigacion Disciplinaria en Conservacion y Mejoramiento de Ecosistemas Forestales INIFAP (SARH) Ave. Progreso 5, Coyoacan, Mexico 04110 D.F. (Mexico))
The environmental hazard caused by smelter slags from the Sta. Maria de la Paz mining district in Mexico
1997
Manz, M. | Castro, L.J. (UFZ Centre for Environmental Research Leipzig-Halle, Department of Chemical Ecotoxicology, PO Box 2, D-04301 Leipzig (Germany))
Distribution and abundance of meiofauna in a subtropical coastal lagoon in the south-eastern gulf of California, Mexico
1997
Noguera, S.E.G. | Hendrickx, M.E. (Estacion Mazatlan, Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Autonoma de Mexico, Ap. Postal 811, 82000, Mazatlan, Sinaloa (Mexico))
Environmental and pollution condition of the Huizache-Caimanero Lagoon, in the north-west of Mexico
1997
Guillermo Galindo, R.J. | Alejandra Medina, J.M. | Cecilio Villagrana, L. | Leonardo Ibarra, C. (Escuela de Ciencias del Mar, Universidad Autonoma de Sinaloa, Paseo Claussen s/n Mazatlan, 82000 Sinaloa (Mexico))
Chlorinated hydrocarbons in marine sediments of the Baja California (Mexico)-California (USA) border zone
1998
Gutierrez-Galindo, E.A. | Mendoza, L.M.R. | Munoz, G.F. | Celaya, J.A.V. (Instituto de Investigaciones Oceanologicas Universidad Autonoma de Baja California, P.O. Box 2516 Ensenada, Baja California (Mexico))
Influence of water circulation on marine and faecal bacteria in a mussel-growing area
1996
Lizarraga-Partida, M.L. | Cardenas, G.V. (Centro de Investigacion Cientifica y de Educacion Superior de Ensenada (CICESE), Km 107 carr. Tijuana-Ensenada, Baja California (Mexico))
