An Update on Tierra Blanca, Devastated by Cancer
By Antonio De Jesús Aguado
The study conducted in Tierra Blanca by UNAM (Universidad Nacional Autónoma de México) regarding a mineral that causes lung cancer and mesothelioma revealed only the tip of the iceberg. The state government has also conducted an investigation, finding just one case of cancer in the area. However, Dr. Marcos Adrián Ortega, involved in the investigations, assured that the person detected with cancer could be the one who will pass away in the days to come. This is probable because there is an annual index of death due to lung cancer or mesothelioma of 1.2 persons in the area.
In 2012, the Geosciences Center of the UNAM Juriquilla campus, started—at the request of the then mayor Núñez—an investigation in the community of Tierra Blanca de Abajo, a rural community approximately three kilometers away from Cruz del Palmar, in order to find out the causes of the cancer that was killing the inhabitants. The main economic activities are agriculture, cattle-raising, and extraction of sand and gravel from the San Damián river, which is impossible to cross by car due to the lack of a proper bridge. The only way to get out of Tierra Blanca when the river current is strong is a hanging bridge. The community has potable water and electricity but no sanitation. The inhabitants (who now know the source of the disease) were born there and resist leaving their roots. They know that if they have developed the cancer that incubates for 10-15 years, they will die wherever they go. Moreover, evacuation of the area is the last solution proposed by the scientists from the UNAM.
Ortega, one of the doctors involved in the investigation, has a master’s degree and a doctorate in hydrogeology from the University of Waterloo in Ontario, Canada. A teacher at UNAM, he has been involved in investigation for 25 years. Ortega told Atención that in 1998 a resident from San José Iturbide requested him to conduct an investigation about the behavior of the Laja river aquifer that has an extension of 7,000 square meters and crosses 20 municipalities. In the study, researchers learned that the aquifer is polluted with arsenic and fluoride that destroy the dental enamel, cause osteoporosis, and magnify depression that leads to suicide. After that, they held several talks about water, open to general public, which Núñez attended.
The last talks were held at CEDESA (Center of Rural and Agricultural Development) in Dolores Hidalgo, currently directed by Graciela Martínez. This organization works mainly in the construction of cisterns for rainfall water collection. In Tierra Blanca, there were too many cases of lung cancer, according to Ortega. “Honestly, we avoided the problem because that was not related to our investigation topics. The health problem, I thought, must be seen to and solved by the governmental authorities since lung cancer is not caused by water but from breathing certain types of mineral particles,” he said.
Later in 2011, Silvia Valdéz Haro, head of the Sanitary Jurisdiction called a regional meeting attended by several specialists and scientists. One of them commented that there was a mineral, erionite, that could cause cancer. Later, Núñez asked Ortega to conduct an investigation in the area with UNAM to discover the causes of the cancer in the area. She signed an agreement with the university for 500 thousand pesos. Currently, the investigation is being financed by UNAM.
Minerals and numbers
The researchers started the investigation using epidemiologic information provided by Valdéz Haro. They found out that 45 deaths were registered in the community from 2000 to 2012. Of those, 18 were caused by two types of cancer. Eight men and six women died due to lung cancer, and three men and a woman passed away because of mesothelioma. These numbers indicate a 1.2 percent annual death rate due to erionite in the community.
The scientists started to research the type of mineral causing the deaths in Tierra Blanca and also to determine whether erionite, a volcanic mineral formed in underground waters, was really in the area. Previously, in 1998, the UNAM had found and published the presence of that mineral in a path from Guanajuato to Juventino Rosas. In Tierra Blanca more than 200 samples of rocks, containing minerals such as chrome, asbestos, nickel, cadmium, and beryllium, were collected to be analyzed. They found out that,although some minerals were in the area, they were in low concentrations that were not perilous to the inhabitants’ health.
Those in charge of the study used several methodologies. Finally, they found the source of the problem, situated three kilometers north of Tierra Blanca. There they located volcanic rocks that have been in the area for more than 30 million years. They were underground in the past but later, due to erosion, they were dragged throughout the streams to the San Damián river. “The mineral is volcanic glass,” states Ortega. He says in addition that the place where the source is located is the most beautiful area in the community, used as a recreational place. With an artificial dam. It is also the place where the settlers graze their livestock. The mineral has been dragged to the paths used by children going to school and has been found in the crops. (Consuming the products from those lands does not represent a problem for the locals. The problem is that the mineral is breathable in the area near the source and in the river, where a cubic centimeter contains more than 100 million microscopic crystals of erionite.)
The authorities need a better strategy
Geologist Ortega assured that more investigation is in order to know where in the area the erionite is spread or sheltered. He remarked that two more cases of this kind of cancer have been detected in Zacatecas and Jalisco. “The study has just begun,” he said.
Recently, Governor Miguel Márquez commented on the State Secretary of Health’s investigation of people in the community, which found just one case of cancer. Ortega stated that the study was conducted on living people. He added that the authorities did not take into account the 1.2 percent of people who have passed away yearly from this cancer, making it clear that one case corresponds to a person who could die in the months to come and would represent the annual 1.2 percent average.
Ortega also said that in 2012 researchers made a special presentation to current local authorities, assistant mayor José Luis Chagoyán and head of the Ecology Department Erick Velázquez, to inform them about this problem so they could do something to assist the community. “We have not had any answers from them,” commented Dr. Ortega. The group also held a presentation for the inhabitants of Tierra Blanca, advising them to pave their roads, reforest the areas where the erionite has been found, and construct family orchards to minimize the volatility of the crystals. Regardless of the source of the mineral, Ortega commented that it needs to be isolated through a large engineering project. He did not elaborate on this.
Recently the scientists responsible for the investigation also had a meeting with representatives of the Secretariat of Communications and Transportation, presenting the possibility of the existence of erionite in the planned Autopista Bicentenario construction area. He offered them help to find the best areas free of erionite, but they have not responded or held other meetings.
The inhabitants of the area where the road could be constructed have commented several times that the construction would impact their tangible and intangible heritage, and they are afraid of the public health problem that the construction could cause if the road is built in areas polluted with erionite. The geologist hopes that authorities will take the problem seriously and can offer a solution.