Central America, Southern Mexico, and other regions of the world have been suffering from chronic kidney disease of unknown etiology (CKDu; e.g. Orantes et al., 2011). Researchers in Sri Lanka have proposed that the origin of the illness is attributed to exposure to agrochemicals and arsenic and heavy metals in soils and groundwater (Jayasumana et al., 2013). In Sri Lanka, the source of arsenic has been found to be fertilizers and pesticides. In Central America, several causes have been suggested for this illness including toxic effects of agrochemicals (e.g. Orantes, 2011) and high ambient temperatures and chronic dehydration (Peraza et al., 2012). In El Salvador (Figure 1), previous research using step-wise multivariate regression found statistically significant correlation between the spatial distribution of the number of sick people per thousand inhabitants and the percent area cultivated with sugar cane, cotton, and beans, and maximum ambient temperature, with sugar cane cultivation as the most significant factor (Vandervort et al., submitted). Ambient temperature has only a minor effect as the regression variable on the incidence of this disease. Spatial distribution of the number of patients per thousand inhabitants for all the stages of the illness, ambient temperature, and the percent of the land cultivated with sugar cane is presented in Figure 2.