Lowdown on Roundup Part II

Benbrook, 2016a

Charles M. Benbrook, “Trends in glyphosate herbicide use in the United States and globally,”  Environmental Sciences Europe, 2016, 28:3, DOI 10.1186/s12302-016-0070-0.


BACKGROUND: Accurate pesticide use data are essential when studying the environmental and public health impacts of pesticide use. Since the mid-1990s, significant changes have occurred in when and how glyphosate herbicides are applied, and there has been a dramatic increase in the total volume applied.

METHODS: Data on glyphosate applications were collected from multiple sources and integrated into a dataset spanning agricultural, non-agricultural, and total glyphosate use from 1974–2014 in the United States, and from 1994–2014 globally.

RESULTS: Since 1974 in the U.S., over 1.6 billion kilograms of glyphosate active ingredient have been applied, or 19 % of estimated global use of glyphosate (8.6 billion kilograms). Globally, glyphosate use has risen almost 15-fold since so-called “Roundup Ready,” genetically engineered glyphosate-tolerant crops were introduced in 1996. Two-thirds of the total volume of glyphosate applied in the U.S. from 1974 to 2014 has been sprayed in just the last 10 years. The corresponding share globally is 72 %. In 2014, farmers sprayed enough glyphosate to apply ~1.0 kg/ha (0.8 pound/ acre) on every hectare of U.S.-cultivated cropland and nearly 0.53 kg/ha (0.47 pounds/acre) on all cropland worldwide.

CONCLUSIONS: Genetically engineered herbicide-tolerant crops now account for about 56 % of global glyphosate use. In the U.S., no pesticide has come remotely close to such intensive and widespread use. This is likely the case globally, but published global pesticide use data are sparse. Glyphosate will likely remain the most widely applied pesticide worldwide for years to come, and interest will grow in quantifying ecological and human health impacts. Accurate, accessible time-series data on glyphosate use will accelerate research progress.  FULL TEXT

EPA, 1973

Environmental Protection Agency, May 24, 1973, Memo on Toxicology of Glyphosate.


This memo reports on the results of several toxicology studies on glyphosate for humans and animals and is one of the earliest available regulatory documents for this herbicide.  FULL TEXT

EPA, 1975

Environmental Protection Agency, “Request for the establishment of final tolerances,” for Pesticide Petition # 5F1536, 1975.


Request for the establishment of final tolerances for combined negligible residues of the herbicide N-phosphonomethyl glycine (glyphosate) and its metabolite aminomethyl phosphonic acid in or on forage grasses (crop group) and soybean forage and hay at 0.2 ppm; and various crops grains and soybeans at 0.1 ppm.  FULL TEXT

EPA, 1977

Environmental Protection Agency, July 1, 1977, Memo on glyphosate toxicology studies.


This memo briefly describes 8 glyphosate toxicology studies by the laboratory IBT. FULL TEXT

EPA, 1979

Environmental Protection Agency, Petition proposing the establishment of tolerance for residues of glyphosate, November 13, 1979.


Petition by Monsanto Agricultural Products, Inc. requests the establishment of a tolerance for residues of glyphosate and its metabolite in stone fruit at 0.2 ppm and refers to an ADI of 0.05 mg/kg/day.  FULL TEXT

EPA, 1982a

Environmental Protection Agency, February 9, 1982, Memo on Lifetime Feeding Study in Rats with Glyphosate, Office of Pesticide and Toxic Substances.


Not Available


EPA, 1982b

Environmental Protection Agency, Memo on increase of temporary tolerances for glyphosate on soybeans, Office of Pesticides and Toxic Substances, September 3, 1982.


This memo discusses a request to increase the tolerance for glyphosate on soybean grain and hulls and describes an ADI of 0.1 mg/kg/day.  FULL TEXT

EPA, 1985a

Environmental Protection Agency, Memo on the Consensus Review of Glyphosate, Office of Pesticides and Toxic Substances, March 4, 1985.


This memo reports on a meeting of the Toxicolgy Branch in February 1985 to discuss the potential oncogenic response of glyphosate where the group classified glyphosate as a Category C oncogen, meaning it may cause cancer in humans. FULL TEXT

EPA, 1985b

Environmental Protection Agency, Memo on glyphosate mouse oncogenicity study, Office of Pesticides and Toxic Substances, April 3, 1985.


This memo describes conclusions that glyphosate was found to be cancer- causing in male mice, causing kidney tumors in a dose-related manor and includes the consensus report by the committee.  FULL TEXT

EPA, 1986a

Environmental Protection Agency, March 11, 1986, Memo on Additional Histopathological Evaluations of Chronic Feeding Study of Glyphosate in Mice, Office of Pesticides and Toxic Substances.


Report of review of additional pathological and statistical information on mice kidney tumors.