Agriculture Reference
In-Depth Information
that is absorbed into the rat's system from a one-time exposure is not enough
to cause illness. But if that same small amount is absorbed day after day,
enough poison will be absorbed into the rat's system to cause illness and
death.
Table 7.1
Typical precautionary statements on pesticide labeling.
Highly Toxic
Moderately Toxic
Slightly Toxic
Acute Oral
"Fatal if swallowed,"
or "Can kill you if
swallowed. "
"Harmful or fatal if
swallowed," or “May
be fatal if swal-
lowed.”
“Harmful if swal-
lowed,” or “May be
harmful if swal-
lowed,”
Acute Inhalation
“Poisonous if in-
haled,” or “Can kill
you if breathed,”
combined with the
statement “Do not
breathe dust vapors
or spray mist.”
“Harmful or fatal if
inhaled,” or “May be
fatal if breathed,”
followed by a state-
ment such as “Do not
breathe dusts, va-
pors. or spray mist.”
“Harmful if inhaled,”
or “May be harmful
if breathed,” com-
bined with the state-
ment “Avoid breath-
ing dusts, vapors or
spray mist.”
Acute Dermal
“Fatal if absorbed
through the skin,” or
“Can kill you by skin
contact,” combined
with the statement
“Do not get on skin
or clothing.”
“Harmful or fatal if
absorbed through the
skin,” or “May be
fatal by skin con-
tact,” followed by a
statement such as
“Do not get on skin
or clothing.”
“Harmful or fatal if
absorbed through the
skin,” or May be
harmful by skin
contact,” combined
with the statement
“Avoid contact with
skin or clothing.”
Skin Irritation
“Corrosive—causes
severe skin burns,”
combined with the
statement “Do not get
on skin.”
“Causes skin irrita-
tion,” or “Causes skin
burns,” followed by a
statement such as
“Do not get on skin.”
“May irritate skin,”
combined with the
statement “Avoid
contact with skin.”
Eye Irritation
“Corrosive—causes
irreversible eye
damage,” or “Causes
severe eye burns or
blindness,” combined
with the statement
“Do not get in eyes.”
“Causes eye irrita-
tion,” or “Causes eye
burns,” followed by
a statement such as
“Do not get in eyes.”
“May irritate eyes,”
combined with the
statement “Avoid
contact with eyes.”
Sometimes repeated exposures to a pesticide or family of pesticides will
result in a delayed effect, but a larger exposure will cause an acute effect. Or-
ganophosphate and carbamate pesticides inhibit a chemical, called cholinester-
ase, in the nervous system of humans. A large exposure causes immediate
acute illness. Smaller exposures cause no apparent problem at first. They
inhibit the cholinesterase, but not enough to cause immediate illness. Small,
repeated exposures to these pesticides over several days or weeks may greatly
reduce cholinesterase levels in the body. At that point, even a small exposure
to a pesticide with relatively low cholinesterase-inhibiting properties may
trigger severe illness.
