The epidemic of chronic kidney disease among agricultural workers and manual laborers in recent years; chronic kidney disease has emerged as a major illness among workers in hot climates. It was first identified in the 1990s by clinicians treating sugar cane workers in Central America. In 2012, it claimed roughly 20,000 lives and has now been identified in California, Florida and in Colorado’s San Luis Valley.
“The researcher looked at all the available literature on the subject and asked, `What do we know today? Where are the gaps?” said the study’s lead author Lee Newman, MD, MA, director of the Center for Health, Work & Environment and professor in the Dept. of Environmental & Occupational Health at the Colorado School of Public Health. “The researcher hoping to synthesize everything we know so far for a framework for moving forward.”
Chronic kidney disease
“Some pesticides are nephrotoxic, and these could possibly contaminate the water supply,” Johnson said. “Indeed, there are studies showing the epidemic in Sri Lanka is greatest in areas where there are shallow wells in which toxins might become concentrated.” Sri Lankan farmers exposed to glyphosate showed an increased risk for chronic kidney disease. Still, the levels in wells very low and studies in Central America turned up little glyphosate.
Along with pesticides, the researchers looked at heavy metals as a possible culprit. Lead and cadmium, known to cause kidney injury; have reported in the soils of Sri Lanka and Central America. Other potential causes include infectious diseases that can hurt the kidneys such as the hantavirus and leptospirosis; common in sugar cane workers. Genetic factors are also a possibility.
Combination of heat
Therefore the common factors are heat exposure and heavy labor,” Newman said. But heat stress and persistent dehydration can cause kidney damage. The disease is moving into the U.S. with agricultural workers in Florida, California’s Central Valley and Colorado’s San Luis Valley reporting incidences of the illness. So Newman and Johnson believe the epidemic is caused by a combination of heat and some kind of toxin and they recognize the need to take preventative action immediately.
That means ensuring workers get adequate breaks; drink enough fluids and spend time in the shade. It also means maintaining clean water supply, free of chemicals toxic to the kidneys. When clinicians detect clusters of patients with chronic kidney disease who work for the same employer or in similar jobs the authors said; “they should contact occupational health and safety and public health professionals to promote investigations of workplace conditions.”