Glyphosate is an herbicide. It is applied to the leaves of plants to kill both broadleaf
plants and grasses. The sodium salt form of glyphosate is used to regulate
plant growth and ripen specific crops.
Glyphosate was first registered for use in the U.S. in 1974. Glyphosate is one of
the most widely used herbicides in the United States. People apply it in agriculture
and forestry, on lawns and gardens, and for weeds in industrial areas.
Some products containing glyphosate control aquatic plants.
What are some products that contain glyphosate?
Glyphosate comes in many forms, including an acid and several salts. These
can be either solids or an amber-colored liquid. There are over 750 products
containing glyphosate for sale in the United States.
IMPORTANT: Always follow
label
instructions and take steps to minimize
exposure. If any exposures occur, be sure to follow the First
Aid instructions on the product label carefully. For additional treatment advice, contact the Poison
Control
Center at 800-222-1222. If you wish to discuss
a
pesticide
problem, please call
NPIC at 800-858-7378.
How does glyphosate work?
Glyphosate is a non-selective herbicide, meaning it will kill most plants. It prevents the plants from making
certain
proteins that are needed for plant growth. Glyphosate stops a specific enzyme pathway, the shikimic acid
pathway.
The shikimic acid pathway is necessary for plants and some microorganisms.
How might I be exposed to glyphosate?
You can be exposed to glyphosate if you get it on your skin, in your
eyes or breathe it in when you are using it. You might swallow some
glyphosate if you eat or smoke after applying it without washing
your hands first. You may also be exposed if you touch plants that
are still wet with spray. Glyphosate isn't likely to vaporize after it is
sprayed.
Pure glyphosate is low in toxicity, but products usually contain other ingredients that help the
glyphosate get
into
the plants. The other ingredients in the product can make the product more toxic. Products containing
glyphosate
may cause eye or skin irritation. People who breathed in spray mist from products containing glyphosate
felt
irritation
in their nose and throat. Swallowing products with glyphosate can cause increased saliva, burns in the
mouth and
throat, nausea, vomiting, and diarrhea. Fatalities have been reported in cases of intentional ingestion.
Pets may be at risk if
they touch
or eat plants that are still wet with
spray
from products containing glyphosate. Animals
exposed to products with glyphosate may drool, vomit, have diarrhea, lose their appetite, or seem
sleepy.
What happens to glyphosate when it enters the body?
In humans, glyphosate does not easily pass through the skin.
Glyphosate that is absorbed or ingested will pass through the body relatively quickly.
The vast majority of glyphosate leaves the body in urine and feces without being changed into another
chemical.
Is glyphosate likely to contribute to the development of cancer?
Animal and human studies were evaluated by regulatory agencies in the USA, Canada, Japan, Australia, and the
European Union, as well as the Joint Meeting on Pesticide Residues of the United Nations and World Health
Organization (WHO). These agencies looked at cancer rates in humans and studies where laboratory animals
were
fed high doses of glyphosate. Based on these studies, they determined that glyphosate is not likely to be
carcinogenic. However, a committee of scientists working for the International Agency for Research on Cancer
of
the WHO evaluated fewer studies and reported that glyphosate is probably carcinogenic.
Has anyone studied non-cancer effects from long-term exposure to
glyphosate?
Long-term feeding studies in animals were assessed by the U.S. Environmental Protection Agency (EPA) and
other
regulatory authorities. Based on these evaluations, they found there is no evidence glyphosate is toxic to
the
nervous or immune systems. They also found it is not a developmental or reproductive toxin.
Are children more sensitive to glyphosate than adults?
As required by the Food Quality Protection Act, the EPA has determined that children are not more sensitive
to
glyphosate as compared to the general population.
Glyphosate binds tightly to soil. It can persist in soil for up to 6 months depending on the climate and
the type
of soil
it is in. Glyphosate is broken down by bacteria in the soil.
Glyphosate is not likely to get into groundwater because it binds tightly to soil. In one study, half the glyphosate in
dead leaves broke down in 8 or 9 days. Another study found that some glyphosate was taken up by carrots
and
lettuce
after the soil was treated with it.
Can glyphosate affect birds, fish, or other wildlife?
Pure glyphosate is low in toxicity to fish and wildlife, but some products
containing glyphosate may be toxic because of the other ingredients in
them. Glyphosate may affect fish and wildlife indirectly because killing the
plants alters the animals' habitat.
For more detailed information about glyphosate please visit the list of referenced
resources or call
the National Pesticide Information Center, Monday - Friday, between 8:00am - 12:00pm Pacific Time
(11:00am -
3:00pm Eastern Time) at 1-800-858-7378 or visit us on the web at
http://npic.orst.edu.
NPIC
provides objective, science-based
answers to
questions about pesticides.
Date Reviewed: 2010; limited revisions made: March 2019
Please cite as: Henderson, A. M.; Gervais, J. A.; Luukinen, B.; Buhl,
K.; Stone, D.; Cross, A.; Jenkins, J. 2010.
Glyphosate General Fact Sheet;
National
Pesticide
Information Center, Oregon State University Extension Services. http://npic.orst.edu/factsheets/glyphogen.html.
NPIC fact sheets are designed to answer questions
that
are
commonly
asked by the general public about pesticides that are regulated by the
U.S. Environmental Protection Agency (US EPA). This document is
intended to be educational in nature and helpful to consumers for
making decisions about pesticide use.
