Yucatán Drinking Water Contaminated by Fecal Matter from Pig Megafarms

A report released October 21, 2026, by Greenpeace Mexico and Greenpeace International reveals widespread fecal contamination of drinking water sources and cenotes in Mexico's Yucatán state, impacting the sole freshwater supply for approximately 5 million people[1][2][3]. The report, titled "The Price of Pork: How Illegal Pig Megafarms Are Destroying Mexico's Underground Springs," links this pollution to industrial pig megafarms, with over 90% operating illegally without mandatory environmental impact assessments[1][2][6].

This contamination poses severe health risks to residents, particularly Indigenous Maya communities who rely on these sources for drinking water[2][3][12]. Their constitutional rights, including rights to a healthy environment and autonomy, are violated, and traditional livelihoods are negatively impacted[2][9][13][14][15]. The unique karst geology of the Yucatán Peninsula allows pollutants to rapidly enter the underground aquifer, making the problem urgent for public health and environmental protection[1][2][3][18].

What the records show

Independent laboratory tests commissioned by Greenpeace in August 2026 examined water samples from 17 sites across several communities in Yucatán[1][2][4]. The results showed critical levels of fecal bacteria, with multiple sites reaching the maximum laboratory quantification limits for total coliform bacteria in 16 of 17 samples, and fecal coliforms in 13 samples[1][3]. These tests also detected significant organic pollution and nitrates[1][3]. While Greenpeace's methodology could not definitively determine the source of the fecal waste, additional studies provided specific evidence[3][4][11].

The To'one Ja'o'on Maya Water and Territory Defense Network, in collaboration with Johns Hopkins University and the National Autonomous University of Mexico, used the specialized DNA marker method 'Pig2Bac'[2][17][19]. Their research confirmed the presence of pig fecal matter in water samples at five overlapping sites in Mérida, Izamal, Kinchil, Chapab, and Maxcanú[2][17]. These findings provide direct evidence of swine waste in the water supply[2][17]. Local communities have reported health issues, including acute pharyngitis from the burning of pig waste by megafarms[7][8]. One megafarm holding 49,000 pigs, located just 250 meters from a town, was linked to gastrointestinal and respiratory diseases due to water contaminated with nitrites, nitrates, and fecal bacteria[1].

Calls for Action

Greenpeace Mexico is urging Mexican authorities to impose an immediate moratorium on new and expanding industrial livestock operations across the Yucatán Peninsula[1][2]. The organization also calls for the prosecution of illegal megafarms and the upholding of the rights of Indigenous Maya communities[1][2]. José Luis Perlasca, Campaigner at Greenpeace Mexico, stated that for years, rapid expansion of industrial activities has occurred in a vulnerable hydrological system, causing widespread contamination[2]. The report highlights a systemic regulatory failure, with over 90% of industrial pig megafarms in the region operating without mandatory environmental impact assessments[2][6].

What we could not confirm

We could not confirm any public statements from the operators of the industrial pig megafarms regarding the findings of the Greenpeace report or the allegations of contamination and illegal operation. We also could not confirm a specific response from Mexican authorities to the calls for action made by Greenpeace Mexico and other organizations following the report's release.