Acephate is an
organophosphate
In organic chemistry, organophosphates (also known as phosphate esters, or OPEs) are a class of organophosphorus compounds with the general structure , a central phosphate molecule with alkyl or aromatic substituents. They can be considered a ...
foliar
A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, ste ...
and soil
insecticide
Insecticides are substances used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are used in agriculture, medicine, industry and by consumers. Insecticides are claimed to b ...
of moderate persistence with residual systemic activity of about 10–15 days at the recommended use rate. It is used primarily for control of
aphid
Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A t ...
s, including resistant species, in vegetables (e.g. potatoes, carrots, greenhouse tomatoes, and lettuce) and in horticulture (e.g. on
rose
A rose is either a woody perennial flowering plant of the genus ''Rosa'' (), in the family Rosaceae (), or the flower it bears. There are over three hundred species and tens of thousands of cultivars. They form a group of plants that can be ...
s and
greenhouse
A greenhouse (also called a glasshouse, or, if with sufficient heating, a hothouse) is a structure with walls and roof made chiefly of Transparent ceramics, transparent material, such as glass, in which plants requiring regulated climatic condit ...
ornamentals). It also controls
leaf miner
A leaf miner is any one of numerous species of insects in which the larval stage lives in, and eats, the leaf tissue of plants. The vast majority of leaf-mining insects are moths ( Lepidoptera), sawflies ( Symphyta, the mother clade of wasp ...
s,
caterpillar
Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths).
As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder Sym ...
s,
sawflies
Sawflies are the insects of the suborder Symphyta within the order Hymenoptera, alongside ants, bees, and wasps. The common name comes from the saw-like appearance of the ovipositor, which the females use to cut into the plants where they lay ...
,
thrips
Thrips ( order Thysanoptera) are minute (mostly long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Different thrips species feed mostly on plants by puncturing and sucking up the contents, although a few are ...
, and spider mites in the previously stated crops as well as
turf
Sod, also known as turf, is the upper layer of soil with the grass growing on it that is often harvested into rolls.
In Australian and British English, sod is more commonly known as ''turf'', and the word "sod" is limited mainly to agricult ...
, and
forestry
Forestry is the science and craft of creating, managing, planting, using, conserving and repairing forests, woodlands, and associated resources for human and environmental benefits. Forestry is practiced in plantations and natural stands. Th ...
. By direct application to mounds, it is effective in destroying imported fire ants.
Acephate is sold as a soluble powder, as emulsifiable concentrates, as pressurized aerosol, and in
tree injection Tree injection—also known as trunk injection or stem injection,—is a method of targeting a precise application of pesticides, plant resistance activators, or fertilizers into the xylem vascular tissue of a tree with the purpose of protecting the ...
systems and granular formulations.
As of 2012, the EPA no longer allows the usage of acephate on green beans grown in the United States.
Toxicology
It is considered non-
phytotoxic
Phytotoxins are substances that are poisonous or toxic to the growth of plants. Phytotoxic substances may result from human activity, as with herbicides, or they may be produced by plants, by microorganisms, or by naturally occurring chemical react ...
on many crop plants. Acephate and its primary metabolite,
methamidophos
Methamidophos, trade name "Monitor," is an organophosphate insecticide.
Crops grown with the use of methamidophos include potatoes and some Latin American rice. Many nations have used methamidophos on crops, including developed nations such as Spa ...
, are toxic to
Heliothis
''Heliothis'' is a genus of moths in the family Noctuidae. It was first described by Ferdinand Ochsenheimer in 1816. Some of the species have larvae which are agricultural pests on crop species such as tobacco, cotton, soybean and pigeon pea. S ...
spp. that are considered resistant to other organophosphate insecticides. Acephate emits toxic fumes of various
oxides
An oxide () is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– (molecular) ion. with oxygen in the oxidation state of −2. Most of the E ...
of
phosphorus
Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ear ...
,
nitrogen
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
, and
sulfur
Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula ...
when heated to decomposition. Symptoms of exposure to acephate include a slight irritation of eyes and skin.
The U.S. annually uses 4–5 million pounds of acephate. The author of one book states that acephate throws off the navigation systems of
white-throated sparrow
The white-throated sparrow (''Zonotrichia albicollis'') is a passerine bird of the New World sparrow family Passerellidae.
Etymology
The genus name ''Zonotrichia'' is from Ancient Greek (, ) and (, ). The specific ''albicollis'' is from Lati ...
s and other songbirds, making them unable to tell north from south.
[Bridget Stutchbury (2007) ''Silence of the Songbirds'', Walker & Company, ]
References
* U.S. EPA Office of Pesticide Programs.
* Extension Toxicology Network. Pesticide Information Profiles.
* Cooperative Extension Offices of Cornell University, Oregon State University, the University of Idaho, and the University of California at Davis.
* Institute for Environmental Toxicology, Michigan State University.
External links
Acephate General Fact Sheet - National Pesticide Information Center*
ttp://www.epa.gov/pesticides/reregistration/REDs/factsheets/acephate_fs.pdf EPA Acephate Reregistration Eligibility Decision*
Lepitect - Soil injected Pesticide for Ornamental Use
{{Acetylcholine metabolism and transport modulators
Acetylcholinesterase inhibitors
Pesticides
Phosphoramidothioates
Leaf miners