Gerardo Gold-Bouchot

Publications (44) View all

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  Available from: Gerardo Gold-Bouchot

  Article: Contaminants in the coastal karst aquifer system along the Caribbean coast of the Yucatan Peninsula, Mexico.

  Chris D Metcalfe, Patricia A Beddows, Gerardo Gold Bouchot, Tracy L Metcalfe, Hongxia Li, Hanneke Van Lavieren
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  ABSTRACT: Intensive land development as a result of the rapidly growing tourism industry in the "Riviera Maya" region of the Yucatan Peninsula, Mexico may result in contamination of groundwater resources that eventually discharge into Caribbean coastal ecosystems. We deployed two types of passive sampling devices into groundwater flowing through cave systems below two communities to evaluate concentrations of contaminants and to indicate the possible sources. Pharmaceuticals and personal care products accumulated in the samplers could only have originated from domestic sewage. PAHs indicated contamination by runoff from highways and other impermeable surfaces and chlorophenoxy herbicides accumulated in samplers deployed near a golf course indicated that pesticide applications to turf are a source of contamination. Prevention and mitigation measures are needed to ensure that expanding development does not impact the marine environment and human health, thus damaging the tourism-based economy of the region.
  Environmental pollution (Barking, Essex: 1987) 04/2011; 159(4):991-7. · 3.43 Impact Factor
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  Available from: Gerardo Gold-Bouchot

  Article: Tamoxifen affects the toxicokinetics of o,p'-DDT in male Nile Tilapia (Oreochromis niloticus).

  María Del Rocío Barreto-Castro, Lisbeth Enith Gómez-Martínez, Gerardo Gold-Bouchot
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  ABSTRACT: The goal of the present study was to evaluate the role of Tamoxifen (TAM), in the distribution and/or elimination kinetics of o,p'-DDT, in male tilapias. A non-compartmental analysis was chosen to describe the time course of o,p'-DDT plasma concentrations. Mean plasma concentration of o,p'-DDT following IP administration indicates a very complex kinetic profile. Tamoxifen decreased the o,p'-DDT mean half-life (t½) from 20.38 to 16.11 days, the Mean Residence Time (MRT) from 28.7 to 23.23 days, and clearance (CL) from 0.0031 to 0.001 mL/min. The distribution pattern of o,p'-DDT in tissues and the clearance in plasma suggest that storage points mediated through the membrane-receptor lipophilicity can be involved.
  Bulletin of Environmental Contamination and Toxicology 11/2010; 85(6):545-9. · 1.02 Impact Factor
• Article: The characterization of cytosolic glutathione transferase from four species of sea turtles: Loggerhead (Caretta caretta), green (Chelonia mydas), olive ridley (Lepidochelys olivacea), and hawksbill (Eretmochelys imbricata).

  Kristine L Richardson, Gerardo Gold-Bouchot, Daniel Schlenk
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  ABSTRACT: Glutathione s-transferases (GST) play a critical role in the detoxification of exogenous and endogenous electrophiles, as well as the products of oxidative stress. As compared to mammals, GST activity has not been extensively characterized in reptiles. Throughout the globe, most sea turtle populations face the risk of extinction. Of the natural and anthropogenic threats to sea turtles, the effects of environmental chemicals and related biochemical mechanisms, such as GST catalyzed detoxification, are probably the least understood. In the present study, GST activity was characterized in four species of sea turtles with varied life histories and feeding strategies: loggerhead (Caretta caretta), green (Chelonia mydas), olive ridley (Lepidochelys olivacea), and hawksbill (Eretmochelys imbricata). Although similar GST kinetics was observed between species, rates of catalytic activities using class-specific substrates show inter- and intra-species variation. GST from the spongivorous hawksbill sea turtle shows 3-4.5 fold higher activity with the substrate 4-nitrobenzylchloride than the other 3 species. GST from the herbivorous green sea turtle shows 3 fold higher activity with the substrate ethacrynic acid than the carnivorous olive ridley sea turtle. The results of this study may provide insight into differences in biotransformation potential in the four species of sea turtles and the possible health impacts of contaminant biotransformation by sea turtles.
  Comparative Biochemistry and Physiology Part C Toxicology & Pharmacology 06/2009; 150(2):279-84. · 2.62 Impact Factor
• Source

  Available from: José Vinicio Macías-Zamora

  Article: Passive air sampling of organochlorine pesticides in Mexico.

  Fiona Wong, Henry A Alegria, Terry F Bidleman, Víctor Alvarado, Felipe Angeles, Alfredo Avila Galarza, Erick R Bandala, Idolina de la Cerda Hinojosa, Ignacio Galindo Estrada, Guillermo Galindo Reyes, Gerardo Gold-Bouchot, Jose Vinicio Macías Zamora, Joaquín Murguía-González, Elias Ramirez Espinoza
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  ABSTRACT: The spatial and temporal variation of organochlorine pesticides (OCs) in air across Mexico was investigated by deploying passive samplers at eleven stations across the country during 2005-2006. Integrated samples were taken over three-month periods and quantified for DDT compounds, endosulfans, toxaphenes, components of technical chlordane, hexachlorocyclohexanes (HCHs), and dieldrin. Enantiomers of chiral chlordanes and o,p'-DDT were determined on chiral stationary phase columns as an indicator of source and age. Results are discussed in combination with pumped air samples taken at four other stations in southern Mexico during 2002-2004. DDT and its metabolites, endosulfan and toxaphene were the most abundant OCs detected in all sampling sites. Atmospheric concentrations of SigmaDDT (p,p'-DDT + o,p'-DDT + p,p'-DDE + o,p'-DDE + p,p'-DDD + o,p'-DDD) ranged from 15 to 2360 pg m(-3) with the highest concentrations found in southern Mexico and the lowest found in northern and central Mexico. A fresher DDT residue was observed at sites with greater DDT use and in the southern part of the country, as shown from the higher FDDTe = p,p'-DDT/(p,p'-DDT + p,p'-DDE) and nearly racemic o,p'-DDT. This agrees with the former heavy use of DDT in the endemic malarious area of the country. A local hotspot of endosulfan was identified at an agricultural area in Mazatlan, Sinaloa, with a annual mean concentration of SigmaENDO (endosulfans I + II + endosulfan sulfate) = 26,800 pg m(-3). At this site, higher concentrations of SigmaENDO were recorded during the winter (November to February) and spring (February to May) periods. From back trajectory analysis, this coincides with a shift in the air mass coming from the Pacific Ocean (May to November) to the inland agricultural area (November to May). The elevated SigmaENDO observed is likely due to the local agricultural usage. HCHs, chlordanes, transnonachlors, and dieldrin were more evenly distributed across the country likely due to them being aged residues and more diffuse in the environment. In contrast, hotspots of endosulfans, DDTs, and toxaphenes were observed as they were heavily used in localized agricultural or malarious regions of Mexico.
  Environmental Science and Technology 03/2009; 43(3):704-10. · 5.23 Impact Factor
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  Available from: M. Leopoldina Aguirre-Macedo

  Article: The checkered puffer (Spheroides testudineus) and its helminths as bioindicators of chemical pollution in Yucatan coastal lagoons.

  Daniel Pech, Víctor M Vidal-Martínez, M Leopoldina Aguirre-Macedo, Gerardo Gold-Bouchot, Jorge Herrera-Silveira, Omar Zapata-Pérez, David J Marcogliese
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  ABSTRACT: The suitability of using helminth communities as bioindicators of environmental quality of the Yucatan coastal lagoons status was tested on the checkered puffer (Spheroides testudineus) in four coastal lagoons along the Yucatan coast. The concentration of chemical pollutants in sediments, water quality parameters, helminth infracommunity characteristics, as well as fish physiological biomarkers, including EROD (7-ethoxyresorufin-O-deethylase) and catalase activities, were measured. Results from sediment analyses demonstrated the presence of hydrocarbons, organochlorine pesticides and polychlorinated biphenyls at varying concentrations, some of which exceeded the Probability Effect Level (PEL). Significant negative associations among organochlorine pesticides, infracommunity characteristics and fish physiological responses were observed in most of the lagoons. Results suggest that EROD activity and parasite infracommunity characteristics could be useful tools to evaluate the effects of chemical pollutants on the fish host and in the environment. Importantly, certain parasites appear to influence biomarker measurements, indicating that parasites should be considered in ecotoxicological studies.
  Science of The Total Environment 02/2009; 407(7):2315-24. · 3.29 Impact Factor