Nearly half of the wells that supply water to the residents of San Miguel de Allende, Guanajuato, have exceeded safe levels of arsenic and fluoride at least once in the last decade, according to information provided by the municipality through its transparency system.
Laboratory results show that 12 of the municipality’s 25 water supply sources are unsafe for human consumption, exceeding Mexican regulations and international recommendations.
The Lomas de San Miguel well, for example, has repeatedly doubled safe levels of arsenic and tripled the recommended levels for fluoride. In response to another request for information, the municipality indicated that this well supplies the Olimpo, Lindavista, Santa Julia, and San Felipe Neri neighborhoods, as well as the Magnolias and Tierra Adentro subdivisions, located a few kilometers from the town’s historic and tourist center.
Analysis of the Ejido de Tirado well shows that the water has had high levels of arsenic since 2014, reaching 0.0247 mg/L in one of its subsequent measurements. Furthermore, it consistently has one of the highest fluoride levels in the entire municipality, peaking in November 2020, when it yielded 6.26 mg/L, six times the safe level. This well supplies water to 11 neighborhoods.
The Mexiquito II, Otomí, Esmeralda, San Luis Rey II, Ventanas, La Paz, and La Vista wells have had high fluoride levels throughout the entire decade analyzed. The Aristos well only had one out-of-standard measurement during that period, and the Mexiquito III well is slightly above the permitted level; while the Nigromante well has also had problems with arsenic.
This information was not publicly known, as this Guanajuato municipality decided to withhold the report on the water quality of its wells, considering that it “could affect or cause disturbances (…) It is determined that the information related to the analyses could actualize or enhance a risk or threat,” according to a response to the information issued by EL UNIVERSAL for the development of the report “Guanajuato has been drinking poison for decades.”
However, the Institute for Access to Public Information for the state of Guanajuato determined that the levels of contamination in the water reaching homes in this municipality are information of public interest, and required the municipality to submit the laboratory studies conducted on its wells between 2014 and December 2024.
San Miguel de Allende is internationally recognized as a tourist attraction and has been declared a World Heritage Site by UNESCO. It is considered a site of significant architectural beauty that has found a niche in luxury tourism, with high-end hotels and restaurants that generate an economic impact exceeding $300 million each year.
174,615 people live here, employed in the service sector—associated with tourism—as well as in commerce, manufacturing, and agriculture. It is also one of the seven municipalities that make up the Upper Laja River Basin, which has suffered from poor water quality for decades.
The newly obtained information is consistent with studies conducted by the other six municipalities: Dolores Hidalgo, San Luis de la Paz, Doctor Mora, San José Iturbide, San Felipe, and San Diego de la Unión: the Basin that supplies them is overexploited, and the water obtained from the territory contains high levels of contaminants that pose a risk to human health.
The studies obtained for the 2014-2024 period were analyzed under the WHO recommendation for arsenic, which establishes that water should not contain more than 0.01 mg of this element per liter. For fluoride, the updated NOM-127-SSA1-2021 was used, which states that water should not contain more than 1.0 mg/L.
For this analysis, we considered the notes of the organization Caminos del Agua, which has studied this issue in the state and has taken action to improve people’s quality of life. They stated: “We believe that there is no healthy level of arsenic and that the presence of any amount of arsenic in drinking water could pose a health problem.”
Furthermore, they continue, “we believe this value (NOM 2021) is safer for health (…) It is important to keep in mind that fluoride poses an even greater danger to infants and children.”
According to the World Health Organization (WHO), the presence of these natural elements in drinking and cooking water is detrimental to health. Daily use, when it contains arsenic, is associated with lung, kidney, and cardiovascular diseases, as well as diabetes and cancer.
Furthermore, drinking contaminated water severely impacts the lives of children, who are more likely to experience learning and memory deficiencies, with long-term impacts.
Furthermore, people who consume fluoridated water often experience stained teeth, structural damage to teeth, and cavities. They may also develop abnormal hardening, calcification, and deformities in bones, tendons, and ligaments.
Throughout the region, people experience joint, headache, and gum pain. Kidney failure is common but little studied as a problem derived from drinking contaminated water, among other conditions.
The municipal government of San Miguel de Allende was asked to comment on the findings of this study, but had not yet responded by press time.
Source: eldiariodecoahuila
