General Description
White crystalline solid. Melting point 173-175°C. Sinks in water. A selective herbicide used for season-long weed control in a variety of crops.
Reactivity Profile
ATRAZINE(1912-24-9) undergoes slow hydrolysis at 158° F under neutral conditions. Hydrolysis is more rapid in acidic or alkaline conditions. Forms salts with acids .
Air & Water Reactions
Insoluble in water.
Hazard
Hematologic, preproductive and develop-
mental effects. Questionable carcinogen.
Health Hazard
Irritates eyes and skin. If ingested, irritates mouth and stomach.
Health Hazard
The acute toxicity of atrazine for mammals is very low. In addition, there is hardly any
resorption via the skin due to its low solubility. Atrazine does not irritate the skin or the
eyes. It is easily resorbed after oral intake and within 24 h, more than 50% is excreted via
urine. During the passage, atrazine is completely metabolized mainly by way of oxidative
dealkylation of the amino group and reaction of the chlorine atom with endogenic thiolic
reagents.
Exposures to atrazine cause damage to the liver, kidney, and heart in animals. It has also
been shown to cause changes in blood hormone levels in animals, which affect ovulation
and the ability to reproduce. In animal experiments, mutagenic or teratogenic effects have
not been discovered. There is little data about the health effects of atrazine in humans. In
Germany, atrazine has not been classed as toxic.
Potential Exposure
Atrazine is an herbicide and plant
growth regulator used for season-long weed control in corn,
sorghum, and certain other crops. Banned for use as a pesticide
in the EU. US annual use . 75 millon pounds.
Fire Hazard
Special Hazards of Combustion Products: Irritating hydrogen chloride and toxic oxides of nitrogen may be formed.
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Seek medical attention immediately.
If this chemical has been inhaled, remove from exposure,
begin rescue breathing (using universal precautions, including
resuscitation mask) if breathing has stopped and CPR if
heart action has stopped. Transfer promptly to a medical
facility. When this chemical has been swallowed, get medical attention. Give large quantities of water or milk
and induce vomiting. Do not make an unconscious person
vomit.
Shipping
UN2763 Triazine pesticides, solid, toxic, Hazard
Class: 6.1; Labels: 6.1-Poisonous materials.
Incompatibilities
Incompatible with oxidizers (chlorates,
nitrates, peroxides, permanganates, perchlorates, chlorine,
bromine, fluorine, etc.); contact may cause fires or explosions.
Keep away from alkaline materials, strong bases,
strong acids, oxoacids, epoxides.
Waste Disposal
Atrazine is hydrolyzed by
either acid or base. The hydroxy compounds are generally
herbicidally inactive, but their complete environmental
effects are uncertain. However, the method appears
suitable for limited use and quantities of triazine. Atrazine
underwent .99% decomposition when burned in a polyethylene
bag, and combustion with a hydrocarbon fuel would
appear to be a generally suitable method for small quantities.
Combustion of larger quantities would probably
require the use of a caustic wet scrubber to remove nitrogen
oxides and HCl from the product gases.
Definition
ChEBI: A diamino-1,3,5-triazine that is 1,3,5-triazine-2,4-diamine substituted by a chloro group at position 6 while one of hydrogens of each amino group is replaced respectively by an ethyl and a propan-2-yl group.
Production Methods
Atrazine is prepared by reacting cyanuric chloride with one
equivalent of ethylamine, followed by one equivalent of
isopropylamine in the presence of an acid-binding agent.
Agricultural Uses
Atrazine is the generic name for 2-chloro-4-ethylamino-
6-isopropylamino-s-triazine.A trazine is an example of
photosynthesis inhibitors and herbicides.
Atrazine was the first s-triazine used in maize. The use
of this herbicide and others in the same group has
expanded to selective application in perennial crops and
orchids as well as for non-crop and industrial sites.
Agricultural Uses
Herbicide, Plant growth regulator: Not approved for use in EU countries. A U.S.
EPA restricted Use Pesticide (RUP). In 2009 a report from
the Natural Resources Defense Council (NRDC) reported
that atrazine is the most commonly detected pesticide in
U.S. waters. Atrazine is a selective pre-and post-emergence herbicide used for the control of broadleaf and
grassy weeds in crops, such as corn (field and sweet),
guava, hay, macadamia nuts, range grasses for the establishment of permanent grass cover on range lands and pastures in Oklahoma, Nebraska, Texas and Oregon, wheat,
residential and recreational turf and sod farms, sorghum,
sugarcane, pineapples, and Christmas trees and ornamentals. It is also used in forestry and, at higher application
rates, for non-selective weed control in non-crop areas.
It is the most widely used pesticide in the United States.
Use data from 1900 to 1997 indicate that approximately
76.5 million pounds of atrazine active ingredient is used
domestically each year. Certified herbicide workers may
spread atrazine on crops or crop lands as a powder, liquid,
or in a granular form. Atrazine is usually used in the spring
and summer months. For it to be active, atrazine needs to
dissolve in water and enter the plants through their roots.
It then acts in the shoots and leaves of the weed to stop
photosynthesis. Atrazine is taken up by all plants, but in
plants not affected by atrazine it is broken down before it
can have an effect on photosynthesis. Atrazine degrades
into hydroxy compounds and chlorotriazine degradates.
The application of atrazine to crops as a herbicide accounts
for almost all of the atrazine that enters the environment,
but some may be released from manufacture, formulation,
transport, and disposal. Atrazine does not tend to accumulate in living organisms such as algae, bacteria, clams, or
fish, and, therefore, does not tend to build up in the food
chain. Atrazine can be applied by ground boom sprayer,
aircraft, tractor-drawn spreader, rights-of-way sprayer,
hand-held sprayer, backpack sprayer, lawn handgun, pushtype spreader, and bellygrinder.
Trade name
AI3-28244®; AATRAM®; AATREX®;
ACTINITE PK®; ACTINIT A®; AGIMIX®
Atrazine; AKTIKON®; AKTIKON PK®; AKTINIT
A®; ALAZINE®; ARGEZIN®; ATAZINAX®;
ATERBUTEX®; ATERBUTOX®; ATLAS ATRAZINE®;
ATLAZIN D-WEED®; ATRANEX®; ATRASINE®;
ATRATAF®; ATRATOL®; ATRAZINEK®;
ATRAZINE 90DF®; ATREX®; AXIOM® Atrazine;
AZINOTOX®; BICEP®; BLADEX/ATRAZINE
(2:1) 80 W®[C]; BUCTRIL + ATRAZINE GEL®[C];
CANDEX®; CEKUZINA-T®; CHROMOZIN®; CO-OP
ATRAZINE®[C]; CRISATRINA®; CRISAZINE®;
CYAZIN®; DOW ATRAZINE 80 W HERBICIDE®[C];
ERUNIT 500 FW®; FARMCO® ATRAZINE;
FENAMIN®; FENATROL®[C]; FIELD MASTER®;
FLOWABLE ATRAZINE®; G 30027®; GEIGY 30,027®;
GESAPRIM®; GESOPRIM®; GRIFFEX®; GRIFFIN
ATRAZINE 90 DRY FLOWABLE HERBICIDE®[C];
HAVILAND ATRAZINE LINURON WEED
KILLER®[C]; HELENA ATRAZINE TECHNICAL®[C];
GUARDSMAN® herbicide (mixture of atrazine and di-
methenamid); HELENA BRAND ATRAZINE®[C];
HERBATOXOL®; HERBIMIX SC®; HERBITRIN 500
BR®; HUNGAZIN®; INAKOR®; LADDOK®; LANCO
ATRAZINE®[C]; LARIAT®; LEADOFF®; MAGIC
CARPET FERTILIZER WITH ATRAZINE®[C];
MALLET PM BROMOXYNIL, ATRAZINE
BROADLEAF HERBICIDE®[C]; MARKSMAN®;
MARZONE ATRAZINE®[C]; MITAC®; NEW
CHLOREA®; NU-TRAZINE 900 DF®; NU-ZINOLE
AA®; OLEOGESAPRIM®; PATRIOT®; PITEZIN®;
POSMIL®; PRIMATOP®; PRIMOLE®; PROKIL
ATRAZINE 80 W®[C]; RADAZIN®; RADIZINE®;
READY MASTER®; RESIDOX®; SHELL® ATRAZINE
80 W HERBICIDE[C]; SIMAZAT®; STRAZINE®
TRIAZINE A 1294; TRIPART® ATRAZINE 50 SC;
VECTAL®; WEEDEX®; WONUK®; ZEAZIN®;
ZEAZINE®
Pharmacology
In plants, themajor
pathways of atrazine transformation include hydroxylation,
N-dealkylation, and glutathione conjugation. Hydroxylation
of atrazine and other s-triazines occurs in a wide range of plants and is considered a detoxification
mechanism because hydroxyatrazine is not phytotoxic.
Hydroxylation is catalyzed via reaction with the naturally
occurring compound, benzoxazinone (127). A hypothetical
ether-linked intermediate has been proposed to undergoes
hydrolysis to produce hydroxylated triazine and
regenerated benzoxazinone. This reaction occurs in many
susceptible and resistant plant species, and the rate of
this reaction is governed by the amount of benzoxazinone
present in the tissue. The hydroxylation reaction predominates
in root tissue, whereas GSH conjugation is more
prominent in leaf tissue of plants containing a GST that
has substrate specificity for atrazine. Because atrazine
is a photosystem II (PS II) inhibitor, possession of a rapid
detoxification system, such as a specific GST, is paramount
to provide tolerance to this compound.
Carcinogenicity
An increase in mammary adenomas
and fibroadenomas was observed in female rats fed
1000 ppm, but not 500 ppm atrazine or less for their lifetime.
An increase in the incidence of mammary carcinomas was
seen at 70, 500, and 1000 ppm, but not at 10 ppm. The
biological significance of these findings is not known but may
be related to a hormonally mediated mechanism. Rats
fed 375 or 750 ppmatrazine for 2 years showed an increase in
mammary tumors in males at 750 ppm. Uterine carcinomas
increased in both groups and the incidence of malignant
tumors also increased in both sexes.
Environmental Fate
Atrazine is highly persistent in soil. In soil and water, atrazine degrades by hydrolysis, followed by biodegradation by soil microorganisms. Hydrolysis is rapid in acidic or basic environments, but is slower around neutral pH. Sunlight and evaporation do not affect its removal rate. Atrazine can persist for longer than 1 year under dry or cold conditions. It is moderately to highly mobile in soils with low clay or low organic matter content. Because it does not adsorb strongly to soil particles and has a lengthy half-life (60 to >100 days), it has a high potential for groundwater contamination despite being only moderately soluble in water. It is frequently detected in drinking water wells.
storage
Color Code—Blue: Health Hazard/Poison: Store ina secure poison location. Prior to working with this chemicalyou should be trained on its proper handling and storage.Should be stored in tightly closed containers away fromstrong acids.
Toxicity evaluation
According to US EPA, the underlying mechanism for tumor
induction in female SD rats involves a reduction in the release
of gonadotropin releasing hormone (GnRH) from the hypothalamic–
pituitary–gonadal axis in the rats, followed by
attenuation of the afternoon pituitary LH surge, leading to
a lengthening of the estrus cycle that increases estrogen levels
that in turn is associated with an increased incidence of
mammary tumors in SD rats. The decrease GnRH release
follows these postulated events: hypothalamic changes results
in an increase in the release of corticotropin releasing
hormone (CRH), elevated CRH stimulates release of adrenocorticotropic
hormone (ACTH) from the pituitary, elevated
ACTH stimulates production of corticosterone and progesterone
by the adrenal, and some or all of these events
decrease GnRH release. Atrazine and some of its metabolites
act to attenuate the spontaneous preovulatory LH surge, block
the gonadal steroid inducted LH surge and attenuate
concomitant GnRH neuronal activation, inhibit LH secretion,
and increase the concentration of GnRH in the median
eminence (a measure of reduced release). This mode of action
(premature reproductive aging or senescence) hastens the
onset of mammary gland tumors.
The central nervous system (CNS) mode of action that
results in altered pituitary hormone function, especially LH and prolactin (PRL) secretions, occurs in both adults and the
young. The triazine-mediated changes in the hypothalamus–
pituitary–gonadal axis relating to neuroendocrine and
neuroendocrine-related developmental and reproductive
toxicity are considered relevant to humans. On the other hand,
the exact mechanism by which the mode of action changes
neurotransmitters and neuropeptides within the CNS is not
understood. It was noted that although atrazine alters hypothalamic
norepinephrine and dopamine, these effects do not
necessarily represent its primary site of action, but that these
CNS alterations may be a signal of potential upstream effects
on other neurotransmitters. It is unclear if atrazine directly
affects the hypothalamus, setting off the cascade of events, or
affect indirectly through the hypothalamus–pituitary–adrenal
axis or both
