Abstract In response to the recent review by Gillezeau et al., The evidence of human exposure to glyphosate: A review, Environmental Health 1/19/19, here we report additional glyphosate biomonitoring data from a repository of urine samples collected from United States farmers in 1997–98. To determine if glyphosate exposure could be identified historically, we examined urine samples from a biorepository of specimens collected from US dairy farmers between 1997 and 98. We compared samples from farmers who self-reported glyphosate application in the 8 h prior to sample collection to samples from farm applicators who did not report using glyphosate. Of 18 applicator samples tested, 39% showed detectable levels of glyphosate (mean concentration 4.04 μg/kg; range:1.3–12) compared to 0% detections among 17 non glyphosate applicator samples (p-value