The Sala IV constitutional court Wednesday ordered the central government to make a detailed study of why tap water in Guanacaste contains arsenic. It also told officials to provide the region with potable water that does not contain arsenic and to determine how the chemical can be removed.
This was the decision long awaited by residents of the area. The unanimous decision named the Ministerio de Salud and the Instituto Costarricense de Acueductos y Alcantarillados.
Residents of the area, including Bagaces and Cañas, filed the constitutional court appeal in mid-April after waiting for the central government to take action. They noted that more than a year ago, President Laura Chinchilla declared an emergency based on the problems with the water, but nothing has been done since.
The court added that the chemical can produce ailments such as degeneration of the liver, cardiac damage and damage to blood vessels. The decision said that the problem could affect a vast area of the country.
Arsenic is naturally occurring in rocks here and some has been added to the soil by small-scale gold mining over the years.
The original presidential decree cited problems in communities in Alajuela province and in the canton of Bagaces, Cañas and La Cruz in Guanacaste. The court also specified northern Alajuela province.
In its decision the court said that the World Health Organization sets the safe limit for human consumption of arsenic at 10 micrograms per liter of water. That’s 10 parts per billion. Acueductos y Alcantarillados provides water with up to 187 micrograms of arsenic per liter, said the court.
The court gave the health ministry and the water company six months to determine the cause of the contamination in conjunction with the Servicio Nacional de Aguas Subterráneas Riego y Avenamiento.
Meanwhile, the government agencies were told to adopt the necessary means so that the affected population receives the water it needs. The court also said that the quality of the water should be checked every three months.
Once the agencies determine the cause of the arsenic pollution, they were told to make the information available to the public and to take steps to mitigate the problem.
That may not be easy. A news story Tuesday said that researchers from the University of Exeter Medical School compared eight different technologies, all of which claim to make drinking water safe. They found that most of the studies reviewed were found to be of poor quality and missing data and that only two technologies showed good evidence of effectiveness, said a release from BioMed Central
Arsenic in the water supply threatens several hundred million people worldwide, said the study published Friday in BioMed Central’s open access journal Environmental Evidence.
A.M. Costa Rica also has reported that rice soaks up arsenic from polluted ground water. International studies have found high concentrations of arsenic in rice but the harvests in Costa Rica are not checked for this problem.