Since 2002, a disease called Mesoamerican Nephropathy has killed about 20,000 people, mainly men working in sugar cane fields in Nicaragua and El Salvador. The disease attacks the kidneys and eventually results in their failure. So far, there are a number of hypotheses for its cause, including exposure to heavy metals, pesticides, or other chemicals, but so far we don’t know what causes it.
One doctor, Richard J. Johnson, of the University of Colorado Anschutz Medical Campus thinks the cause lies in global warming. His hypothesis is that the disease is caused by chronic and recurrent dehydration. His research team found that sugar cane laborers were consistently working in conditions that would violate heat standards set by the Occupational Safety and Health Administration (OSHA) here in the United States. Despite workers drinking up to 2 liters of water an hour many suffered from dehydration due to the excessive heat out in the sugar cane fields.
Global warming becomes a possible cause of the sugar cane worker’s deaths because the temperatures in these regions have been steadily rising for the last century, by about 0.5 degrees Celsius each year since 1980 alone. That results in higher average temperatures, as well as higher temperature extremes which, coupled with the labor intensive work these men do, results in repeated dehydration.
If Dr. Johnson is right, this would be the first disease directly related to global warming and the first epidemic caused by it. Even if he’s wrong, being dehydrated that frequently is unhealthy. One of the major and serious side effects of dehydration is the overproduction of uric acid in the blood stream.
While we need to do more research on Mesoamerican Nephropathy, and more research into the effects of elevated uric acid levels on the kidneys, Dr. Johnson suggests that those workers need new work patterns. He suggests more frequent hydration with water or electrolyte-containing water, which has been reported to reduce uric acid. Better labor laws would help as well, to prevent workers from becoming dehydrated in the first place.