Watershed-based partnerships for Global Environmental Health: U.S.-Mexico Border
A binational team of scientists, educators, multimedia experts, and government partners are collaborating with community-based organizations to deal with the water/climate/poverty nexus and transboundary environmental risks along the U.S.‐Mexico Border. A UCSD-TV documentary about this project can be viewed on line at : http://www.ucsd.tv/index.aspx?aspxerrorpath=/loslaureles/index.aspx
This project aims to improve environmental public health in the San Diego-Tijuana city-region. The Project is funded and led by the UCSD Superfund Research Program with input from Urban Studies and Planning Program, Scripps Institution of Oceanography, Sustainability Solutions Institute, Center for Iberian and Latin American Studies, Office of International Affairs, UCSD-TV and The Global Action Research Center. The objective is twofold: (1) develop new watershed-based strategies/models that can help the National Institute of Environmental Health Sciences (NIEHS) address Global Environmental Health (GEH), and (2) share the science and technology contributions of UCSD�s Superfund Basic Research Program (SBRP) with urban-regional planning scholars, educators and professionals who are struggling to better understand how problems of the built environment, land use and pollution impact environmental public health.
This project develops a collaborative �living laboratory� approach. The geographic unit of analysis is Los Laureles Canyon�a representative sub-basin of the Tijuana River Watershed spanning the US-Mexico border. More than 65,000 people live in the colonias of Los Laureles Canyon on the Mexican side of the border. Colonias are large irregular human settlements that lack many basic urban services. Accelerated population growth in Los Laureles Canyon has led to chronic problems of sediment, trash and hazardous waste flows into the U.S. coming from Mexico. The inadequate management of sewage, hazardous substances and solid wastes poses chronic risks of exposure to pathogens and environmental toxicants to communities on both sides of the border. Los Laureles Canyon serves as an inspiring rallying point for faculty, students and community-based partners to work together on sustainability solutions. Two specific questions motivate this effort: (1) What is the degree of contamination by Superfund toxicants (PAHs, PCBs and Dioxins and heavy metals) in the soils and sediments of Los Laureles Canyon? and (2) What factors can be used to predict the spatial distribution of contaminants at the sub-watershed and watershed scale? The collection and analysis of these data will help us understand what natural, built environment and human activity factors along the Mexican side of the Tijuana River Watershed contribute to presence/distribution of Superfund chemicals in soil and sediments. In turn, this effort will help identify and prioritize ecological and human health risks in the City of Tijuana and in the binational Tijuana River Watershed, while informing the selection of strategies to reduce or eliminate present and future exposure(s) to Superfund chemicals on both sides of the border.
Initial screening of soil and sediment in the Laureles Canyon subwatershed, with Superfund Basic Research Program (SBRP) biomolecular assays (P450 RGS) showed high levels of AhR ligands, which may potentially include organic toxicants like PAHs, PCB, Dioxins and Furans. The implications for human health and wildlife could be significant. At present, little watershed-based data exists with regards to the spatial distribution of toxicants in the Tijuana River Watershed, making it difficult to assess and prioritize toxicants of concern and implement management strategies that will effectively reduce human exposures and protect wildlife and natural resources. This project will enable us to: 1) work with binational stakeholders in an unprecedented crossborder data collection effort focused on superfund toxicants, 2) relate the environmental health sciences to urban planning and the multiple stressors and risk factors facing fast-growing low income human settlements along the U.S.-Mexico border, and 3) improve our capacity for science communication.
KEYWORDS:
U.S.-Mexico Border, Toxicants, Built Environment, Human Health, SBRP, Superfund, P450HRGS, Risk Assessment, Cross-Border Flows, Colonia.
FIGURES:
Figure 1. The binational Tijuana River Watershed along the U.S.-Mexico border region. Modified from U.S.EPA
Figure 2. Boundaries of Laureles Canyon subwatershed in Tijuana shown in red. The U.S.-Mexico border is shown in yellow. Location of P450 RGS screening sites is shown by numbered markers. Source: Google Earth �
SELECTED REFERENCES:
Anderson, JW, Rossi, SS, Tukey, RH, Vu, T and Quattrochi, LC. 1995. A Biomarker, P450 RGS, for Assessing the Induction Potential of Environmental Samples. Env. Tox. Chem. 14: 1159-169.
Environmental Health Perspectives. 2000a. Bordering on Environmental Disaster. EHP 108:A308-315.
Gersberg RM, Daft D, Yorkey D. 2004. Temporal pattern of toxicity in runoff from the Tijuana River Watershed. Wat. Res. 38:559-568.
Gonzalez EJ, Pham PG, Erickson JE, Baker DB. 2002. Tijuana Childhood Lead Risk Assessment Revised: Validating a GIS Model with Environmental Data. Env. Man. 29:559-565.
IMTA (Instituto Mexicano de Tecnologia del Agua). 2004. Diagnostico Integral de la Subcuenca Hidrologica Los Laureles, Tijuana, B.C. [in Spanish] Resumen Ejecutivo. November 2004. 14 pp. Available: http://icfdn.org/initiatives/llc/RESUMENEJECUTIVOLaureles.pdf [Accessed 13 October 2007]
Pezzoli K and Sarabia H. 2006. Addressing Global Environmental Health Issues Along the U.S-Mexico Border. Newsletter of the Global Planning Educators Interest Group. University of California, San Diego / Superfund Basic Research Program, Research Translation Core: (San Diego, CA) November.
Sarabia, H. 2007. �The Laureles Canyon: A Sustainability Laboratory at the Interface of Urban Sprawl and a Nature Preserve in the U.S-Mexico border.� GPEIG: Newsletter of the Global Planning Educators Interest Group. Fall. Available: http://www.gpeig.org.php5-4.websitetestlink.com/images/uploads/GPEIG-Fall2007_Newsletter.pdf
VISION:
Redevelopment of unsustainable human settlements through community-based participatory research and self-sustaining hands-on projects that address environmental, human health, social and economic needs with economically and culturally viable participatory solutions and technologies.
INSTRUMENTS:
Community-based participatory research, hands-on projects involving community leaders and residents, existing binational forums for government, research and community collaboration and information exchange, biomolecular assays and other emergent technologies in the Environmental Health sciences, local, State, federal and international funding sources.
INSTITUTIONS:
Community-based leaders and organizations, City of Tijuana Planning Institute (IMPLAN), UCSD, U.S. EPA Border 2012 Program, among others.
KNOWLEDGE COMMUNITIES:
Environmental and environmental health scientists, planners, architects, community leaders and members, social scientists, engineers, doctors, etc.
Video Vignettes
Oscar Romo gives a tour of the Tijuana River Estuary (view on SciVee)
The Colonia Diez de Mayo Project, Tijuana, Mexico (view on RWBC web site)
The Tijuana River Watershed (view on RWBC web site)
More video content on RWBC at http://regionalworkbench.org/education/narratives.php
Gallery of photos: http://regionalworkbench.org/gallery/main.php?g2_itemId=3499
News Release: http://www.gpeig.org/index.php/news_announcements/comments/us_mexico_border
Project URL:
http://www.regionalworkbench.org/databank/project_all.php?pid=25
