In the Llanos region, where the Pujiltic sugar mill is located in Venustiano Carranza, domestic, agricultural and industrial waste has turned this site into a point of high contamination.
A recent study carried out by the University of Sciences and Arts of Chiapas (Unicach) revealed the presence of heavy metals in the micro-basins that make up the Grijalva River, whose importance is vital, since it supplies water to communities on the border between Mexico and Guatemala and in the Llanos region. This report warns about the potential risks to human health and the ecosystem, alerting about possible harmful effects on flora, fauna and the food chain of the region.
The research indicates that both the water and sediments in the middle and lower basins of the Grijalva contain dangerous metals, and studies on marine species show that these contaminants accumulate in organisms and can be transferred through the food chain, affecting those who consume aquatic products.
The study highlights the increase in mercury in the basins of the rivers that converge and supply different towns such as Nuevo Paraíso, América Libre, 20 de Noviembre, Laja Tendida, Puy, Venustiano Carranza, Ingenio Pujiltic, Col. Nuevo Tamaulipas, among others. The most toxic metals, such as arsenic, cadmium, chromium, mercury and lead, represent a significant risk, while others such as copper and zinc can also become dangerous if they reach high concentrations.
Biologist Edna Ríos Valdovinos, professor and researcher of renewable energies at Unicach, explained that some heavy metals act as genotoxic agents, altering the genetic material of organisms and causing damage that can even affect future generations. Although metals such as zinc and copper are essential in small quantities, prolonged contact with these and others, such as arsenic, cadmium, chromium, mercury and lead, can be highly toxic.
One of the inhabitants of this region, named Analleli, indicated that she has lived there for more than 30 years. She recalled that since her childhood the waters were cleaner because they used them to wash clothes and household items.
“Now the waste from the factories has contaminated the water a lot, affecting the health of people and animals. Before, you could see fish and now there are not even one left,” she explained.
Currently, they have noticed illnesses in the inhabitants, such as skin allergies, stomach problems, and not only that. The most serious thing is that they have detected that people suffer from cancer or die from it, this due to the contamination not only of the water but of the environment.
“Here, everyone uses this water for drinking, and some, where it is not available, use it directly from the rivers for household services,” said the resident.
The residents have noticed the change in the water, because when they bathe they say it is very rough, and when they wash clothes they use more detergent or, when they bathe, soap, because it does not foam, and even their skin turns white, so they prefer to use bottled water, because it is less harmful, increasing the expense for those who have it, but those with low resources have to use it.
“Not only has the water caused illnesses, but also the smoke causes air pollution, which has caused lung cancer,” said Analleli.
The National Mining Development Program 2001-2006, published in 2003, recognized the potential in Chiapas. According to Mexico’s Mining Administration System, 112 concessions were granted for mineral exploitation in the upper part of the Grijalva River in 2010, with a focus on gold, silver, lead, copper and trisodium phosphate. However, this type of mining, especially open-pit mining, entails serious environmental risks due to the use of water resources and potential contamination by mercury and arsenic.
Ríos Valdovinos mentioned that small communities, which usually obtain their water from surface sources, aggravate the situation by dumping their wastewater on their own land or nearby streams, in addition to using septic tanks for their sewage, increasing the levels of contamination, also detected in the municipality of Motozintla.
“The analysis of four samples of mercury in water, carried out during rainy and dry seasons, revealed that mercury is particularly concentrated in one of the flows that leaves Motozintla de Mendoza, with the metal present in greater quantities both in the water and in the sediments,” he explained.
Biologist Ríos Valdovinos highlighted the importance of using chemical processes such as photocatalysis to degrade contaminants such as drugs, pesticides and antibiotics. This process uses zinc oxide as a catalyst, degrading contaminants such as methylene blue, common in the textile industry.
Maricruz Jiménez Cerda, who also collaborates in the study, explained that this process involves exposing zinc oxide to light at specific periods, achieving the degrading of contaminants in controlled periods.
According to Ríos, this technique could be essential to purify water and reduce the impact on human health, preventing damage to the nervous system and other organs.
Source: elheraldoechiapas
