Line 4Line 4 Copyic/close/grey600play_circle_outline - material
Answers

Question

A recent NYTimes article reports declining soil quality from continued use of glyphosate. What are the facts? I would expect that no-till practices would actually maintain soil quality.

Submitted by: Erin Irish


Answer

Expert response from David Gustafson

Director, ILSI Research Foundation’s Center for Integrated Modeling of Sustainable Agriculture and Nutrition Security (CIMSANS)

Tuesday, 25/11/2014 11:35

Yes, no-till is good for the environment! And that’s one of many important facts that the recent New York Times article ignored. The data show that the use of glyphosate and glyphosate-tolerant crops has helped enable the widespread adoption of conservation tillage practices, not only in the United States but in many other countries as well (Argentina, Brazil, etc.). It is also important to note that although Monsanto first obtained EPA registrations for glyphosate, it is now a generic herbicide and other parties now routinely request revisions in tolerances and use patterns.

 

As you know, no-till or conservation-tillage practices allow farmers to save valuable time and fuel. Instead of relying upon mechanical tillage to kill weeds or winter cover crops prior to planting, they allow these plants to grow and then control them with an application of glyphosate or other herbicide, either before or after the spring crop has emerged. Besides saving the farmer time and money, dropping a tillage operation also does the environment a favor by conserving soil and reducing net greenhouse gas emissions.

 

But there are other benefits as well. No-till soils are known to have healthier biodiversity and result in improved water quality outcomes, through reduced nutrient and sediment runoff. And despite what the New York Times reporter asserted, glyphosate itself does not represent a water-quality concern, due its strong soil binding potential and relatively rapid rate of decomposition.

 

Here are some facts concerning other specific allegations in the New York Times article:

 

  1. The use of glyphosate on crops has no adverse impacts on microbes in the soil.
  2. Although glyphosate can experience particle drift (as with any sprayed material), it has an extremely low runoff potential and its off-site impacts are minimal.
  3. Glyphosate has a large safety margin for mammals, due to a metabolic pathway that is present in plants but does not occur in animals. A comprehensive review of the literature reveals that glyphosate does not pose a health risk to humans, is not a carcinogen or an endocrine disrupter, does not bioaccumulate, is rapidly excreted, does not adversely affect reproduction or development and has no synergistic adverse effect with other herbicides. 

 

World Health Org. Glyphosate and AMPA in Drinking-water WHO Guidelines for Drinking-water Quality, 3rd edition, 2004 Summary Statement, Extract from Ch 12 – Chemical Fact sheets. (pg 379) “…the presence of glyphosate and AMPA in drinking-water does not represent a hazard to human health”

http://www.fao.org/ag/agn/fv/files/1263_WHO_WATER_GUIDELINES.PDF