Veneno en Mi Agua

Country/area: Mexico

Organisation: Data Crítica, Quinto Elemento Lab

Organisation size: Small

Publication date: 13/12/2021

Credit: Patricia Curiel, Gibran Mena, Dzoara Fonseca, Francisco Tinoco


Data Critica uses data analysis and visualization with programming languages to investigate critical issues: the environment and racial, economic, and gender imbalances of power. We share research skills through workshops and courses in partnership with other organizations and present the investigations in innovative ways that get the readers closer to the stories we publish.

Project description:

Veneno en Mi Agua (Poison in my Water) is an investigation and a tool which reveals that the presence of arsenic and fluoride above international limits in well water, once a problem that only affected the two Mexican states of Durango and Coahuila, has spread to 23 states in the last years. It also reveals that the cause of this spreading is not only industrial waste, but the industrial extraction of water, which accelerates the liberation of geological elements in unmonitored wells. The tool allows for the creation of a poster for the population to know and share which monitoring

Impact reached:

The investigation prompted the national Congress, at the Comission of Hydraulic Resources, to contact us in order to have a meeting. The meeting is programmed with the president of this Comission is scheduled to happen on January 18th.

Prior to that, the investigation reached nation-wide TV stations and dozens of local papers, which used the arsenic and fluoride map we built , and the poster maker tools in our investigation to make their own local news reporting in Querétaro, Mazatlán and Baja California Sur.

Columnists in several newspapers took the investigation to demand the Congress to make the prevention of disease (due to the wide spread of arsenic and fluoride in the water, and the lack of monitoring of industrial extraction and an epidemiological program to prevent disease) to be a priority for the 2022 legislative agenda.

Techniques/technologies used:

We used statistical analysis and R programming to extract, clean and analyze data and compare each of the samples to the international limits, which are more strict to México’s, and also to the national limits, and to calculate ratios and main Mexican states affected. We also used geospatial tools such as Qgis to perform a spatial analysis which we showed specialistas, who confirmed that the most affected areas are above volcanic ground, and hence point to the disturbance of underground water flows as the main source of this arsenic and fluoride, in addition to inustrial mining waste, among other industrial practices.

We also used React programming to make an interactive database where each reader can select a state and a municipality and automatically get a downloadable sign with the number of monitoring wells with high levels of either of the substances. In addition, we offer a map of each well visualized according to the level of arsenic and fluoride in different layers, and a table to look up specific years, states or municipalities.

Finally, we delivered the tools with the story of a territory defender in one of the most affected areas in Baja California Sur, Mexico, and reported on the potential solutions to this crisis.

What was the hardest part of this project?

The major challenge of this investigation was to translate the massive database of 122000 records to something the people could action on, this was accomplished by the creation of a dynamic customizable poster, where the readers can select their state and municipality and know the wells that have risky contents of arsenic and or fluoride.

There were several other challenges during this investigation. The first one was to understand the diversity of norms that rule water quality in Mexico and their relationship to international standards, but also under what circumstances there is impact on health. The result was to reveal that Mexico’s quality underground water are twice as permisive as they are in the US and Europe and lead us to select the international health risk guidelines as the basis for the analysis of risk of each sample.

The second challenge was the analysis itself, data cleansing in a database of thousands of municipalities in the 32 Mexican States is always cumbersome, as the names of the wells, towns and states was not uniform throughout the 8 years of data analyzed.

Another hard part of this project was in the reporting aspects to track how the water with arsenic related to people actually drinking it, which we found is the case in the featured area, La Paz, Baja California Sur, where more than 300 hundred people were tested thanks to an academic study in the area. From theres, we linked the data to the human story of the defense of this area against big industry.



What can others learn from this project?

This story’s coverage was national in Mexico, and we got deeper with on ground stories in the most affected place, Baja California Sur, but reporters from the states of Querétaro and Sinaloa have already contacted us with questions about the local affectations. We shared with them the data and explained the context on how this data is  gathered and used to help them build local stories.

A workshop with local reporters is also in order to continue localize the story in more Mexican locations.

Project links: