A report published Tuesday by the environmental organization Greenpeace states that water samples from wells and natural sinkholes in Mexico’s Yucatan state contained fecal bacteria. The report identifies industrial pig farms and municipal wastewater as potential sources of the bacteria found in the region’s primary freshwater source.
The study, conducted in August, involved the testing of 17 sites near the state capital, Merida, by an independent laboratory commissioned by Greenpeace. The locations included household wells, community water points, and cenotes, which are natural sinkholes common to the peninsula.
According to the report, all 17 samples showed some level of contamination linked to fecal waste. The findings indicated that total coliform bacteria reached the test’s upper detection limit in 16 of the samples, while fecal coliforms reached the limit in 13 samples. The initial tests did not distinguish between human and animal waste sources.
However, Greenpeace stated that subsequent testing conducted at Johns Hopkins University and Mexico’s National Autonomous University (UNAM) used a pig-specific DNA marker method known as Pig2Bac. The results from this analysis detected pig fecal matter in the samples, which led the organization to raise what it called “critical accountability questions” regarding nearby farms.
In response to the findings, Greenpeace and local Maya communities called for a moratorium on the development of new industrial livestock operations in the state. The Yucatan Peninsula’s geology consists of porous limestone, which allows surface pollutants to enter the underground aquifer that supplies the region’s water.
A separate United Nations report published in July noted the presence of more than 500 industrial pig farms across Yucatan state. Marcos Orellana, a former U.N. special rapporteur and author of that report, stated that waste from industrial farms can enter the water supply used by local communities.
Providing another perspective, Antonio Zumarraga, vice president of the Yucatan Citizen Scientific Water Observatory, said the local pork industry has invested in water treatment and conservation. Zumarraga attributed the issue to a lack of government action.
The Yucatan state government, Mexico’s national water commission CONAGUA, and Merida’s Association of Pig Farmers did not immediately respond to requests for comment on the report’s findings.
