Regional cooperation with Canada and the United States helps Mexico meet its international obligations
The Commission for Environmental Cooperation (CEC) and Mexico’s National Institute of Ecology (Instituto Nacional de Ecología—INE) in October presented new developments in monitoring persistent, bioaccumulative and toxic substances (PBTS) under Mexico’s National PBTS Environmental Monitoring and Evaluation Program (Programa Nacional de Monitoreo y Evaluación Ambiental de STPB—Proname).
“North America now has environmental monitoring and evaluation programs in all three countries, making it possible to generate reliable information and indicators for making decisions on the management of these types of chemical substances,” said Alma Delia Nava Montes, a biologist who coordinates Proname, as she welcomed North American experts in environmental monitoring of chemical substances to a CEC-sponsored workshop in Mexico City to hear updates on results and work in progress from the coordinators of Mexico’s three active monitoring sites.
Supported by the CEC, Proname was created by the Mexican federal government, through the Ministry of the Environment and Natural Resources (Secretaría de Medio Ambiente y Recursos Naturales—Semarnat) as part of Mexico’s implementation of the Stockholm Convention on Persistent Organic Pollutants. This program and its monitoring work are already generating results that are enhancing research on the environment and, for the first time, linking this research directly to the health of communities, individuals and ecosystems.
Proname’s objective is to study the impacts on the environment and human health from various chemical compounds found in soil, water and air, as well as in plant and animal species.
Participants at the October meeting, including specialists from Canada, Mexico and the United States, heard the results that have been obtained thus far at the three currently operational sites: Valle del Yaqui in Sonora, the Biosphere Reserve Ría Celestún in Yucatán, and most recently, the Biosphere Reserve Sierra de Manantlán in Jalisco.
Valle del Yaqui, Sonora
Dr. Vinicio Macías, in charge of this site in Sonora, reported that, due to the large areas of cropland, monitoring and chemical analysis have been conducted randomly in different locations and communities, as well as water bodies. Found thus far are traces of toxic and persistent substances such as DDT, hexachlorobenzenes, various pesticides, and a series of other compounds.
Dr. Macías also indicated that DDT has remained in cropland soil for over 30 years, due to the intensive use of pesticides, and that in some rivers, monitoring has revealed traces of this pollutant in the livers of the fish analyzed, such as mullet and catfish. The research conducted is particularly important since these fish species are consumed by humans. For this reason, a parallel human biomonitoring study (on blood) was conducted and another, on mother's milk, was begun, both coordinated by the National Institute of Public Health (Instituto Nacional de Salud Pública—INSP). The two studies were presented at the workshop by environmental engineer Sandra Leticia Rodríguez and epidemiologist Dr. Mary Carmen Baltazar Reyes, who are awaiting the results of the blood and maternal milk analyses to know the degree of exposure of the population.
Ría Celestún, Yucatán
Ignacio Ustarán, chemist and director general of Laboratorios ABC Química, Investigación y Análisis S.A. de C.V., indicated that the monitoring of PBTS conducted in Ría Celestún, Yucatán, prior to and including 2010, has detected concentrations of these pollutants. The results of the study are being analyzed and evaluated to see if the levels registered could have effects on the ecosystems in this natural protected area.
Ustarán, contracted by the CEC to develop protocols for standardizing the sampling, analysis, quality control, and results reporting procedures that were developed for implementation at Proname sites, presented these to the workshop and emphasized the importance of applying common criteria for chemical analytical methods, in order to achieve comparable and reliable results that would permit this information to be used internationally by Mexico for the Stockholm Convention of the United Nations Environment Programme, among others.
Biosphere Reserve, Sierra de Manantlán, Jalisco
There was also an opportunity at the meeting to hear about the results obtained at the index site, the Sierra de Manantlán biosphere reserve, which is the most recent Proname site. Teresa Ortuño Arzate, a chemist who is responsible for the site, reported that there are a number of problems resulting from human impact on the environment, since forest fires, grazing and other agricultural activities, open-air burning of trash, poaching, marginalization and poverty, among others, are persistent factors in the region.
Ortuño Arzate reported that sampling conducted in various water bodies, and on soils, sediments, small fish and tree leaves, has revealed concentrations of organochlorine pesticides and polycyclic aromatic hydrocarbons, possibly due as much to the burning of fields and trash, as o the use of agrochemicals. She also reported that passive air sampling equipment has been installed to detect and measure the presence of persistent organic compounds in the air.
As a result of cooperation and the exchange of experiences among the three North American countries, Mexico’s Proname today is generating information that will contribute to decision making and actions to manage persistent, bioaccumulative, and toxic substances in the region. Its medium-term projects include:
At the end of the meeting, experts from the United States, specifically Tony Olsen and Ana Corado (representing the US Environmental Protection Agency), and Navdeep Khera of Environment Canada, shared their experiences and environmental monitoring programs in the two countries. A final plenary session was then held for exchanging ideas and opinions among the representatives of the North American countries, coordinated by Victor Shantora and Ana Patricia Martínez. Those participating agreed to continue efforts aimed at strengthening trinational monitoring of persistent, bioaccumulative, and toxic substances, to generate information useful throughout the region.
Prepared by Arturo Delgado