Glyphosate was first
registered for use in the U.S. in 1974.
Glyphosate is one of the most
widely used herbicides in the USA. People apply it in agriculture and
forestry, on lawns and gardens, and for weeds in industrial areas. Some
products containing glyphosate control aquatic plants.
Glyphosate is an herbicide
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
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.
It is broken down by bacteria in the soil.
Glyphosate is not likely to
get into groundwater because it binds tightly to soil. I
In one study,
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.
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 called the shikimic acid pathway which is
necessary for plants and some microorganisms.
The shikimate pathway
(shikimic acid pathway) is a seven step metabolic route used by bacteria,
fungi, algae, parasites and plants for the biosynthesis of aromatic amino
acids (phenylalanine, tyrosine, and tryptophan).
In humans, glyphosate does not
easily pass through the skin. What 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.
When high doses were
administered to laboratory animals, some studies suggest that glyphosate has
carcinogenic potential. Studies on cancer rates in people have
provided conflicting results on whether the use of glyphosate containing
products is associated with cancer. Some studies have associated glyphosate
use with non-Hodgkin lymphoma.
Glyphosate exposure has been
linked to developmental and reproductive effects at high doses that
were administered to rats repeatedly during pregnancy. These doses made the
mother rats sick. The rat fetuses gained weight more slowly, and some
fetuses had skeletal defects. These effects were not observed at lower
Children have increased sensitivity specifically to