March 30, 2021 | Florida manatees are experiencing chronic glyphosate exposure that is likely to impact their immune system and make them more susceptible to other environmental stressors such as red tide and cold stress, according to a study published in Environment International by a Florida-based team of researchers, led by University of Florida PhD candidate Maite De Maria. Florida manatees, a subpopulation of the West Indian manatee, are listed as threatened under the Endangered Species Act, as populations are under constant threat from human activity in the freshwater ecosystems they rely on. Results find glyphosate in the bodies of 55.8% of Florida manatee samples. Most concerning, the amount of pesticide increased in a straight line over the course of the study. Scientists found no correlation between the size or sex of the manatee and its glyphosate body burden. Authors of the study indicate that it is appropriate to consider glyphosate a “pseudo-persistent” (resulting from continuous runoff or exposure) pollutant, “in which new applications of the herbicide replace the molecules that are being removed,” the study reads. [De María, Maite et al. Chronic exposure to glyphosate in Florida manatee. Environment International. 152: 106493, 2020.]
