The Rural Voice, 1996-06, Page 36ENVIRONMENTAL
CHARACTERISTICS
OF ROUNDUP
For more information about Roundup please call (519) 421-6400
32 THE RURAL VOICE
Roundup herbicide display4a
lavourable combination of
physical properties, chemical
properties and environmental fate
characteristics.
Microbially degrades
Glyphosate, the active ingredient in
Roundup, degrades completely in soil. The
average half-life in soil is less than 60
days, and 90 percent of the glyphos is
degraded into its natural components in
less than 6 months. The breakdown of
glyphosate takes place primarily by normal
soil microorganisms (bacteria), not
chemical decomposition. In addition,
glyphosate does not photodegrade in
sunlight under laboratory conditions.
Furthermore, photodegradation is
considered to be negligible in the field.
The surfactant used in Roundup herbicide
is rapidly degraded by soil microbes. The
surfactant's average soil half-life is less
than one week.
Soil activity
Tests have shown that glyphosate stays
where it is placed because it binds tightly to
most types of soil particles. In a laboratory
study, columns of soil treated with
glyphosate were leached continuously with
water for 45 days.
The test concluded that none of the
glyphosate was released from the soil.
The surfactant used in Roundup herbicide
is tightly adsorbed to soil particles and is
essentially immobile in most sod.
Non-volatile
Since Roundup has a low vapor pressure,
it does not tend to vaporize. This
characteristic reduces the likelihood of any
vapor inhalation and redistribution by air
movement.
Does not bioaccumulate
studies with several species of animals
and fish show minimal tissue retention and
rapid elimination of glyphosate. Studies
show that residues of Roundup herbicide in
agricultural crops are extremely minute —
primarily in the negligible range.
Consequently, the exposure of humans,
livestock and wildlife to residue is
extremely small.
Confirmed by independent studies
Independent, state-of-the-art ecosystem
studies have now been completed. As a
result of all of these combined efforts,
environmental information on glyphosate is
now among the most extensive of any
herbicide on the market today.
Use Roundup with confidence
Based on the results of extensive
toxicological studies in animals, it was
demonstrated that there is no evidence that
glyphosate herbicide causes birth detects,
neurotoxic effects or mutagenic effects. In
addition, data from environmental fate
studies showed that no significant adverse
effects in the environment
occurred following exposure to
Roundup when used
according to label directions
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JUNE 1996 33