Researches from the Regional Institute of Studies on Toxic Substances (IRET – Instituto Regional de Estudios en Sustancias Toxicas) of the National University (UNA – Universidad Nacional) stated that agrochemicals have not been ruled out as potential factors that could be contributing to an unexplained surge in Chronic Kidney Disease (CKD) in Guanacaste, and should therefore be studied.
IRET’s statement came as a reaction to comments made by Martin Zuñiga, the Central American and Caribbean regional director for CropLife Latin America, who denied that the sickness, which is affecting so many people in the province, was provoked by insecticides.
“It is not correct; he cannot make a claim like that,” said Luisa Castillo, the director of IRET-UNA, when she was asked about what Zuñiga said.
CropLife Latin America’s management indicated that they “as an industry” provide their own studies, “…but we do not want to use those studies as a base to demonstrate that chronic renal failure is not caused by pesticides.”
It was requested that Zuñiga provide those studies, but as this article went to print The Voice had not yet received a response.
In the article, “Herbicide Use Could be Associated with Deaths Due to Renal Problems in Guanacaste,” published by The Voice in June, the author explained a possible connection between the use of the herbicide glyphosate and areas in Guanacaste where water has been contaminated with arsenic and heavy metals, leading to high death rates due to kidney diseases.
Later, in the article, “Agrochemical Industries Deny Relation Between Herbicide and Renal Disease,” Zuñiga emphasized the fact that IRET has implemented many long-term studies on the subject.
However, Castillo clarified that IRET has done field studies on pesticides and their relationship with cancer and other chronic diseases, but that the studies on CKD and its unidentified origins have just begun.
In an official press release, IRET emphasized, “In Costa Rica there have been no published studies on human exposure to insecticides and the incidence of Chronic Kidney Disease of unknown origins.”
During his interview with this newspaper, Zuñiga said that IRET’s studies had concluded that the disease “is a problem whose origin has multiple factors, of which pesticides are not considered among the primary ones of interest as being responsible for the disease.”
It its press release, IRET highlighted that, “Until now, there has been a scientific consensus that CKD is a disease with multiple causes stemming from different risk factors.” But they cite a scientific consensus, rather than specific examples of their own studies or national ones.
Castillo said that she had also participated in the First International Research Workshop on Mesoamerican Nephropathy, a meeting held in San Jose in 2012, during which the problems were discussed. “The majority of experts that came from other countries presented it and they arrived at the consensus that CKD is probably caused by multiple factors. But it hasn’t been ruled out that insecticides play a role.”
The factors could be chronic dehydration in hot conditions, possibly with some exposure to some environmental contaminant, another agrochemical, heavy metal or even something yet to be identified.
IRET’s researches also noted that, “People who have chronic kidney disease should be protected from all toxic exposure that could damage their health and renal function and IRET supports regulatory policies and interventions in workplaces to limit exposure to insecticides.”