|Chemical Abstract Number (CAS #)||
|Synonyms||Azinphos ethyl||Ethyl Guthion||Phosphorodithioic acid, O,O-diethyl ester, S-ester with
||EPA Method 8141|
Link to the National Library of Medicine's Hazardous Substances
Database for more details
on this compound.
|Use|| INSECTICIDE-NOT REGISTERED FOR USE IN USA
Azinphos-ethyl was introduced in 1953 by Bayer AG as a nonsystemic insecticide and acaricide.
Although it is no longer registered for use in many countries due to its extreme acute toxicity to
humans, some countries still use azinphos-ethyl for fruits and vegetables, pastures, cotton, cereals,
coffee, potatoes, grapes, citrus, tobacco, rice, hops, and other crops of the forest industry.
Persistent broad spectrum insecticide effective against pests of fruits, vegetables, cotton, and
IT IS USED ON A LARGE RANGE OF CROPS, INCLUDING BEETS, CEREALS, CITRUS,
COFFEE, COTTON, FORAGE CROPS, GRAPES, HOPS, OILSEED CROPS, SOME
ORNAMENTALS, POTATOES, RICE, TOBACCO, TOP FRUIT, VEGETABLES. RATES
ARE GENERALLY 500-750 G AI/HA.
Control of chewing and sucking insects and spider mites on fruit trees (including citrus), vines,
nuts, maize and forestry.
For beetles, caterpillars and their larvae, aphids, spider mites, etc
|Consumption Patterns|| INSECTICIDE-NOT REGISTERED FOR USE IN US
|Apparent Color|| COLORLESS CRYSTALS ; Colorless needles
|Boiling Point|| 111 DEG C @ 0.001 MM HG
|Melting Point|| 53 DEG C
|Molecular Weight|| 345.40
|Density|| 1.284 @ 20 DEG C/4 DEG C
|Environmental Impact|| Azinphos-ethyl would be released to the environment in its use as a non-systemic
insecticide and acaricide on a wide range of crops. It is not marketed in the US or Canada and
consequently there should be no release of this insecticide resulting from its application. When
released on soil, azinphos-ethyl will adsorb strongly to soil, hydrolyze, and probably biodegrade.
Its persistence in soil is unknown. If released in water, azinphos-ethyl will adsorb to sediment and
particulate matter in the soil column. It should hydrolyze, especially in alkaline waters, and
possibly biodegrade. One study suggests that it persists in rice fields for less than two months.
Azinphos-ethyl is not expected to bioconcentrate in fish. In the atmosphere, azinphos-ethyl will
primarily occur as an aerosol and will be removed by gravitational settling. Vapor-phase
azinphos-ethyl will have an atmospheric half-life of 2.2 hr due to its reaction with
photochemically-produced hydroxyl radicals. People will be exposed to azinphos-ethyl from
consuming food products containing residues of the pesticide. Since azinphos-ethyl is not
marketed in the US, azinphos-ethyl residues should only occur in imported foodstuffs.
|Environmental Fate|| TERRESTRIAL FATE: When released on soil, azinphos-ethyl will adsorb strongly to soil,
hydrolyze, and probably biodegrade. Hydrolysis will be more important in moist, alkaline soils.
However, no studies were located concerning azinphos-ethyl's persistence in soil.
AQUATIC FATE: If released in water, azinphos-ethyl will adsorb to sediment and particulate
matter in the water column. It should hydrolyze, especially in alkaline waters, and possibly
biodegrade. A study in which azinphos-ethyl was used on rice fields in the Ebro Delta in Spain
suggests that the azinphos-ethyl may persist for less than two months in this environment and
does not bioconcentrate in fish . Mosquito fish living in the rice fields were sampled at two
month intervals. In September, the fish contained 17 ppb of azinphos-ethyl and only 2 ppb was
detected in November, indicating that azinphos-ethyl was largely removed from both the water
column and fish within the two month period.
ATMOSPHERIC FATE: Azinphos-ethyl has a very low vapor pressure, 2.2X10-7 mmHg at 20
deg C and therefore will primarily occur as an aerosol in the atmosphere . If released into the
air while spraying on crops, azinphos-ethyl will be removed from the atmosphere by gravitational
settling. Vapor-phase azinphos-ethyl will have an atmospheric half-life of 2.2 hr due to its reaction
with photochemically-produced hydroxyl radicals(3,SRC).
|Drinking Water Impact|| SURFACE WATER: Azinphos-ethyl was not detected (detection limit 8 parts/trillion) in
the northern tract of the Adige River in Northern Italy . It was not detected (<10 parts/trillion)
during four samplings from April to August 1988 in the Po River, near Ferrarra, Italy or at two
sites in the Adriatic Sea . No azinphos-ethyl was found in water and seston samples in the upper
Great Lakes collected in the summer of 1974 .
GROUNDWATER: Azinphos-ethyl was not detected in groundwater from 206 wells in a
monitoring program conducted in Germany .