News

2017-12-14 |

Human exposure to glyphosate increased 500 percent since GM crop introduction in the US

Glyphosate is a key ingredient in the herbicide, Roundup. Use of this herbicide has increased approximately 15-fold since 1994 when GM Roundup Ready (RR) glyphosate-tolerant crops were introduced. Used mainly on RR soy and corn, glyphosate is also sprayed on a substantial portion of wheat and oats grown in the US. In July 2017, glyphosate was listed by California as a carcinogen, following the WHO cancer research agency’s classification as glyphosate as “probably carcinogenic” to humans.

A study by the University of California San Diego School of Medicine (report published in the journal JAMA) compared urine excretion levels of glyphosate and aminomethylphosphonic acid (AMPA) in 100 people living in a Southern California community who provided samples during five clinic visits that took place over a 23-year timespan between 1993 to 1996 and 2014 to 2016, starting just before the introduction of GM crops in the US.

The study found that prior to the introduction of GM foods, very few people had detectable levels of glyphosate, but as of 2016, 70% of the study cohort had detectable levels, an increase of approximately 500%. Among this 70%, the mean level of glyphosate increased from 0.203 μg/L in 1993-1996 to 0.449 μg/L in 2014-2016 while the mean level of AMPA went up from 0.168 μg/L in 1993-1996 to 0.401 μg/L in 2014-2016.