Water and Contamination - Situation Summary

Tlamacazapa, Guerrero, Mexico

Conclusion: Tlamacazapa constitutes a multi-factor situation. There are multiple sources of contamination combined with acute poverty and malnutrition. The majority of poor villagers are malnourished and underhydrated and are therefore vulnerable to the harmful effects of chronic exposure to low levels of multiple metals and toxins. These factors indicate a situation of "toxic negative synergy” in which the overall harmful effect of individual metals and toxins is more than the sum of the parts.

Risks: At risk are those who are exposed to multiple sources of toxins, that is, the poor weaver who eats a basic diet of tortillas and salsa, dyes palm and then weaves coloured palm, drinks and cooks with well water or Los Sabinos water, lives in a dirt floor hut, and cooks in a low fire glazed clay pot. Particularly at risk is the pregnant woman and fetus, and the young child who live in these conditions.

Why is the Tlamacazapa situation important? The "toxic synergy” caused by the interactions of toxins and their subsequent effects on the human body is an important concept internationally, as is research on the accumulative effects of metals and toxins on human health. The Atzin focus on "people” and "social process” as well as on the technical aspects of water and other environmental contamination exemplifies the integrated approach that is necessary to achieving a safe and sufficient water supply for all with appropriate maintenance, and the subsequent decrease of overall risk to health.

Major Phases

  • 1997-2000Establishment of presence in village. Bridge activities, knowledge of context and dynamics, slow formation of trusting relationships with villagers; evolution of programming. First water samples taken in mid 2000, with arsenic (As) and lead (Pb) findings.
  • 2001-2003Conduction of small scale programming in three areas: health and healing; water and sanitation; income generation. Development of NGO culture of inquiry; action research. Conduction of small scale research. Dissemination of initial findings.
  • 2004-2007Build up of evidence. Formation of strategic alliances in town and externally. Creative special projects. Continuation of programming in three areas.

Strategy (2007 – present)

  • Build up convincing evidenceof contamination. Conduct research and monitoring, with documentation and dissemination of findings.

  • Emphasize service and developmental programsin Tlamacazapa. Concentrate on construction of dry toilets and tanks and other health and income generation programs in order to respond to acute need and to be of service with the continued creation of good will. Also, to upgrade preparation of villagers through the conduction of training and education sponsorship. Conduct community education through the provision of information: one-on one and in small groups.

  • Form selected local and external alliancesin Mexico and internationally: Instituto Geofisica de UNAM; OPIRG (Ontario); Groundwater Analytical (Mass, USA); catechism youth group in Tlama, Atzin Canada, Atzin USA.

  • Work creativelyto document and disseminate information: article in Hydrogeology Journal; "Reweaving a Life” Art Exhibition (2006-2008); "Reweaving a Life” educational and promotional DVD (2010, 12 minutes); articles in La Jornada, a national newspaper; information packages with summaries of results; publication of Kokonemeh Children of Tlamacazapa, Mexico(2011 in English; 2012 in Spanish); "Tlamacazapa” Photo Exhibition by Cruz (2010-2012) (currently touring in Mexico).

What do we know?

  • The town wells are unsafe with pathogens, nitrate/nitrite and heavy/intermediate metals, and cannot be made safe simply by stopping surface runoff from entering the well. Possibly, well #1 (Tlamapa) could be covered and protected, providing that no one is permitted to live or animals graze on the mostly empty land on the well’s upper side. The other wells should be abandoned completely for any household use.

  • The entire town is highly vulnerable to pollution of water resources (surface water and groundwater) due to thin soil cover, shallow water table and fractured rock aquifer. This means all groundwater below the town is vulnerable to pollution and is already polluted.  Sanitation measures must take special precautions not to leach pollution to water table.

  • Los Sabinos is 4.5 kilometers from Tlama, is the source for the pumped water, and is a relatively natural area. Its water quality recently is likely compromised by cow grazing and insecticide/ herbicide use in surrounding fields. Both lead and arsenic levels above norm have been detected in Los Sabinos water albeit irregularly.

  • Water quality results (2003-2009). Analysis of lead (Pb) and arsenic (As) conducted monthly by GWA – available in yearly summary tables.



Los Sabinos


Mexican Norm (2004, still current)



0 to 0.110 ppm (mg/L)

0 mg/L to .06 ppm (mg/L)

0.01 ppm (mg/L)

0.025 ppm (mg/L)



0 to 0.15 ppm (mg/L)

0 to 0.19 ppm (mg/L)

0.01 ppm (mg/L)

.01 ppm (mg/L)



Yes, above norm in wells 2, 3, 4.

No, but at risk.



Fecal Coliform

Yes, heavy contamination in wells 2, 3, 4.

No, but at high risk.




  • Current water distribution to villagers via the Los Sabinos pumping system in terms of quantity remains well below the WHO standard of a minimum of 20-25 liters per day per person.

  • Arsenic found in water, rock and soil samples, suggesting ore-rich rockis original source. Bioavailability of arsenic from water and from soil dust is of particularly concern.

  • Lead found in water and soil mainly (very low levels in rock) suggesting possible air transportation of lead to water as well as contamination from dumping of dyes and other material on the ground with subsequent transport to wells. However, this doesn’t satisfactorily answer the periodic finding of lead in Los Sabinos.

  • Government officials have not been and continue to not be responsive in any effective manner to this toxicity situation in Tlamacazapa.

What could the water system look like?

  • Piping in from sources at great distance from Tlama not likely feasible due to likely extensive contamination heavy metal problems in regions and prohibitive costs.

  • Rainwater harvesting is a good supplement and emergency source but only easily available in rainy season (June to October). Large scale catchment and storage would need piloting.

  • Los Sabinos currently requires treatment for heavy metals/toxins as well as expansion of quantity to adequately supply the entire town. Two hydrogeological studies need to be conducted at Los Sabinos: 1. pilot toxin/metal removal/ treatment, 2. evaluation of water volume, that is, the sustainable (maximum long-term) yield of the aquifer(s) feeding Los Sabinos vis a vis waters needs of Tlamacazapa and other villages downstream of Los Sabinos. If greater amounts of water are available, the entire system including reservoirs and piping would need upgrading. 


1. Technical (Water and Sanitation)






  • Feasible?: Pilot project: Permeable Reactive Barrier (PRB) in Los Sabinos.

  • Feasible?: Pilot project: Rainwater harvesting - large scale, above well #1.

  • Continuation of water monitoring of selected elements.

TA: expert consultation

State and town formal approval and collaboration. Continued in-kind water analysis.

  • Census 2005 report production and dissemination.




  • Household filters with Fe (removal of As). Investigation into (simultaneous) Pb removal using same filter.

  • Pilot sand filter in Atzin Centre with testing of water pre and post filter.

New funding; would require high subsidization as an intensive initiative with family/ group education and frequent family follow-up.

  • Rainwater harvesting -- tank construction (7,800 liters).

  • Dry toilet construction. Subsidized family program with education on need, use and maintenance.

Ongoing. Requires continuation of funding and partnerships.

Priority Studies

  • Seasonal volume of water in Los Sabinos (UNAM).

UNAM completed study. Don’t have copy.

  • Hydrogeological assessment of LS (UNAM).

UNAM completed study. Have partial copy.

  • Census 2005 (done) – data analysis done, graphics - production and dissemination. Beneficial: repeat census 2011.


  • Social Management and Economy of Water


Atzin/ Chris Wenman – due end 2010.

  • Water Distribution. Evaluation of existing system. Recommendations for improvement.

Need government permission, local and municipal, that will be difficult to obtain, as well as an implemetning partner. New funding.

  • Parasites (Human and Animal) (some done on Helicobacter).

Atzin + pathology partner.

  • Quality of air (not written): kitchens, yards.

Need implementing partner. New funding.

  • Nutritional status (not written).

Atzin and partner. New funding.

2. Reduction of Risk: Individual and Community Education





Individual and community



Replacement of low fire glazed cooking pots– availability, affordability, willingness. One-on-one explanations. Group information: mass, women’s Saturday literacy classes.



ONGOING. Atzin persistence with continuous education. Promoter training schools.


Elimination of use of chemical dyes for palm. Emphasis on use of natural palm and safe decorative features. Safe use of dyes, however, near impossible to safely dispose of dyes on site. One-on-one explanations. Group information: mass, women’s Saturday literacy classes.



Education about contamination/toxins, including water, and effects on health over time. One-on-one or small group explanations. Production of learning resources for distribution. Education on use and maintenance of dry toilets and tanks, hygiene and rainwater collection. Possible ways to prevent/ reduce toxicity.



Nutritional status improvement. Junk food reduction. Vegetable and fruit increased consumption. One-on-one explanations. Group information: demos, mass, women’s Saturday literacy classes. Input into primary and telesecondary schools.



Reduction of kitchen smoke. Promotion and sales of economical and ecological wood rocket cooking stoves. One-on-one explanations. Weekly group demos. Stove promoters with bonus for each sale. Group information: weekly announcements, flyers, women’s literacy classes. Outreach (June and November 2010) to La Montaña region of Guerrero, 70+ women in attendance.


* Improved kitchen ventilation. Not written.