Human Health Effects:
Human Toxicity Excerpts:
Contact allergy from pyrethroids ... has not been observed. /Pyrethroids/
The allergenic properties of pyrethroids /with early pyrethrum preparations/ are marked
in comparison with other pesticides. Many cases of contact dermatitis and respiratory
allergy have been reported. Persons sensitive to ragweed pollen are particularly prone to
such reactions. Preparations containing synthetic pyrethroids are less likely to cause
allergic reactions than are the preparations made from pyrethrum powder. /Pyrethroids/
Pyrethroids are not cholinesterase inhibitors. /Pyrethroids/
Some pyrethroid (eg, deltamethrin, fenvalerate, cyhalothrin, lambda-cyhalothrin,
flucythrinate, and cypermethrin) may cause a transient itching and/or burning sensation in
exposed human skin. /Synthetic pyrethroids/
The clinical manifestations of inhalation exposure to pyrethrins can be local or
systemic. Localized reactors confined to the upper respiratory tract include rhinitis,
sneezing, scratchy throat, oral mucosal edema, and even laryngeal mucosal edema. Localized
reaction of the lower respiratory tract include cough, shortness of breath, wheezing, and
chest pain. An asthmalike reaction occurs with acute exposures in sensitized patients.
Hypersensitivity pneumonitis characterized by chest pain, cough, dyspnea, &
bronchospasm may occur in an individual chronically exposed. /Pyrethrum and synthetic
pyrethroids/
The low toxicity of pyrethroids in mammals is due largely to their rapid
biotransformation by ester hydrolysis and/or hydroxylation. /Pyrethroids/
Lung congestion may occur due to exposure. Local contact may cause contact dermatitis.
Inhalation may cause asthma, coughing, wheezing, running nose and eyes.
Skin, Eye and Respiratory Irritations:
Immediately irritating to the eye. /Pyrethrins/
The chief effect from exposure ... is skin rash particularly on moist areas of the
skin. ... May irritate the eyes.
Medical Surveillance:
Initial medical screening: Employees should be screened for history of certain medical
conditions ... which might place the employee at increased risk from /pyrethroid/
exposure. Chronic respiratory disease: In persons with chronic respiratory disease,
especially asthma, the inhalation of /pyrethroids/ might cause exacerbation of symptoms
due to its sensitizing properities. Skin disease: /Pyrethroids/ can cause dermatitis which
may be allergic in nature. Persons with pre-existing skin disorders may be more
susceptible to the effects of this agent. Any employee developing the above-listed
conditions should be referred for further medical examination. /Pyrethrum/
Populations at Special Risk:
Chronic respiratory disease: In persons with chronic respiratory disease, especially
asthma, the inhalation of /pyrethroids/ might cause exacerbation of symptoms due to its
sensitizing properities. Skin disease: /Pyrethroids/ can cause dermatitis which may be
allergic in nature. Persons with pre-existing skin disorders may be more susceptible to
the effects of this agent. ... /Pyrethroids/
Probable Routes of Human Exposure:
NIOSH (NOES Survey 1981-1983) has statistically estimated that 1,366 workers are
potentially exposed to allethrin in the US(1).
The NOES Survey does not include farm workers. Occupational exposure to allethrin
may occur through inhalation of dust particles or sprays and dermal contact with this
compound at workplaces where allethrin is
produced or used, and especially to workers applying this compound as an insecticide(2).
The transfer of allethrin residues from a
carpeted floor to human subjects wearing dosimeter clothing was measured(3); for gloves,
socks, shirts and tights (subjects performing standardized aerobic exercises), the
transfer coefficient ranged from 2.8 to 34.3 ug allethrin/cu
cm clothing for a period of up to 12.5 hr after applying allethrin
(via foggers) to the carpet(3); transfer rates decreased with time after application(3).
Emergency Medical Treatment:
Emergency Medical Treatment:
| EMT Copyright Disclaimer: |
| Portions of the POISINDEX(R) database are provided here for general
reference. THE COMPLETE POISINDEX(R) DATABASE, AVAILABLE FROM MICROMEDEX, SHOULD BE
CONSULTED FOR ASSISTANCE IN THE DIAGNOSIS OR TREATMENT OF SPECIFIC CASES. Copyright
1974-1998 Micromedex, Inc. Denver, Colorado. All Rights Reserved. Any duplication,
replication or redistribution of all or part of the POISINDEX(R) database is a violation
of Micromedex' copyrights and is strictly prohibited. The following Overview, *** PYRETHRINS ***, is relevant for this HSDB record chemical. |
| Life Support: |
o This overview assumes that basic life support measures
have been instituted.
|
| Clinical Effects: |
SUMMARY OF EXPOSURE
0.2.1.1 ACUTE EXPOSURE
o The mammalian toxicity of natural pyrethrins is
generally low. Very young children are perhaps more
susceptible to poisoning because they may not hydrolyze
the pyrethrum esters efficiently. In humans, allergic
reactions are the main toxic manifestations of
pyrethrin exposure.
1. Pyrethrum and the pyrethrins produce typical type I
motor symptoms in mammals. Severe type I poisoning
may include the following signs in humans:
Severe fine tremor
Marked reflex hyperexcitability
Sympathetic activation
Paresthesia (dermal exposure)
o DERMAL - These compounds are not primary irritants.
The chief effect, however, from exposure is dermatitis.
The usual lesion is a mild erythematous dermatitis with
vesicles, papules in moist areas, and intense pruritus;
a bulbous dermatitis may also occur. Pyrethrins can
cause allergic dermatitis and systemic allergic
reactions.
o INHALATION is the major route of exposure, with airway
irritation as the primary toxic effect. Following
inhalation, a stuffy, runny nose and scratchy throat
are common. Hypersensitivity reactions including
wheezing, sneezing, shortness of breath and
bronchospasm may be noted.
o OCULAR - Eye exposures may result in mild to severe
corneal damage that generally resolves with
conservative care.
o Piperonyl butoxide and other compounds are often added
to pyrethrin insecticides as synergists and may
contribute to toxicity.
o Synthetic pyrethroids, which are related to pyrethrins,
are covered in a separate management.
HEENT
0.2.4.1 ACUTE EXPOSURE
o A stuffy, runny nose and scratchy throat following
inhalational exposure may be noted.
o Eye exposures may result in mild to severe corneal
damage, decreased visual acuity and periorbital edema.
CARDIOVASCULAR
0.2.5.1 ACUTE EXPOSURE
o Hypotension and tachycardia, associated with
anaphylaxis, may occur.
RESPIRATORY
0.2.6.1 ACUTE EXPOSURE
o Hypersensitivity reactions characterized by
pneumonitis, cough, dyspnea, wheezing, chest pain, and
bronchospasm may occur. Rare cases of respiratory
failure and cardiopulmonary arrest have been reported.
NEUROLOGIC
0.2.7.1 ACUTE EXPOSURE
o Paresthesias, headaches, and dizziness are common.
Massive exposure may result in hyperexcitability and
seizures, but this is rare.
GASTROINTESTINAL
0.2.8.1 ACUTE EXPOSURE
o Nausea, vomiting and abdominal pain commonly occur and
develop within 10 to 60 minutes following ingestion.
DERMATOLOGIC
0.2.14.1 ACUTE EXPOSURE
o Irritant and contact dermatitis may develop. Erythema
which mimics sunburn has also been noted after
prolonged repeated exposure.
ENDOCRINE
0.2.16.1 ACUTE EXPOSURE
o Type I motor symptoms following severe poisoning may
result in sympathetic activation.
IMMUNOLOGIC
0.2.19.1 ACUTE EXPOSURE
o Sudden bronchospasm, swelling of oral and laryngeal
mucous membranes, and anaphylactoid reactions have been
reported after pyrethrum inhalation. Hypersensitivity
pneumonitis characterized by cough, shortness of
breath, chest pain, and bronchospasm may be noted.
GENOTOXICITY
o Pyrethrum is not mutagenic in bacterial reversion tests
(Ray, 1991).
|
| Laboratory: |
o Pyrethrin plasma levels are not clinically useful or
readily available.
o Monitor for allergic responses such as asthma or contact
dermatitis.
|
| Treatment Overview: |
ORAL EXPOSURE
o There is no specific antidote for pyrethrin poisoning.
Treatment is symptomatic and supportive and includes
monitoring for the development of hypersensitivity
reactions with respiratory distress. Provide adequate
airway management when needed. Gastric decontamination
is usually not required unless the pyrethrin product is
combined with a hydrocarbon.
o ALLERGIC REACTION: MILD: antihistamines with or
without epinephrine. SEVERE: oxygen, aggressive
airway management, antihistamines, epinephrine (ADULT:
0.3 to 0.5 mL of a 1:1000 solution subcutaneously;
CHILD: 0.01 mL/kg; may repeat in 20 to 30 min),
corticosteroids, ECG monitoring, and IV fluids.
INHALATION EXPOSURE
o INHALATION: Move patient to fresh air. Monitor for
respiratory distress. If cough or difficulty breathing
develops, evaluate for respiratory tract irritation,
bronchitis, or pneumonitis. Administer oxygen and
assist ventilation as required. Treat bronchospasm with
beta2 agonist and corticosteroid aerosols.
EYE EXPOSURE
o DECONTAMINATION: Irrigate exposed eyes with copious
amounts of tepid water for at least 15 minutes. If
irritation, pain, swelling, lacrimation, or photophobia
persist, the patient should be seen in a health care
facility.
DERMAL EXPOSURE
o DECONTAMINATION: Remove contaminated clothing and wash
exposed area thoroughly with soap and water. A
physician may need to examine the area if irritation or
pain persists.
o Vitamin E topical application is highly effective in
relieving paresthesias.
|
| Range of Toxicity: |
o The minimal lethal dose of pyrethrum is not established,
but is probably in the range of 10 to 100 grams.
o Hypersensitivity reactions may be noted, especially
following a chronic dermal or inhalation exposure.
Patients with underlying asthma may be predisposed to
severe bronchospastic reactions after exposure.
|
Antidote and Emergency Treatment:
Treatment is supportive, and most casual exposures require only decontamination.
Topical vitamin E may ameliorate the paresthesias that accompany contact with synthetic
pyrethroids containing an alpha-cyano group (e.g., fenvalerate, cypermethrin,
flucythrinate). /Synthetic pyrethroids/
The additives (e.g. petroleum distillate), when present, represent a greater toxic
threat to the patient than the active ingredient itself. ... Emesis should not be induced
when petroleum distillate additives are present unless the product ingested is estimated
to contain a near lethal dose (1 g/kg) of pyrethrum or pyrethrins. The alert person with
an intact gag reflex & a sublethal pyrethrum ingestion without other toxic
constituents may have emesis induced by ipecac, followed by a saline cathartic &
slurry of activated charcoal. ... Pulmonary & allergic sequelae are treated
symptomatically with airway maintenance, oxygen, & ventilatory assistance as required.
Standard drugs and management protocols may be used for treatment of bronchospasm &
anaphylaxis. Seizures are treated with diazepam. /Pyrethrum and synthetic pyrethroids/
Skin decontamination. Wash skin promptly with soap and water ... . If irritant or
paresthetic effects occur, obtain treatment by a physician. Because volatilization of
pyrethroids apparently accounts for paresthesia affecting the face, strenuous measures
should be taken (ventilation, protective face mask and hood) to avoid vapor contact with
the face and eyes. Vitamin E oil preparations (dL-alpha tocopheryl acetate) are uniquely
effective in preventing and stopping the paresthetic reaction. They are safe for
application to the skin under field conditions. Corn oil is somewhat effective, but
possible side effects with continuing use make it less suitable. Vaseline is less
effective than corn oil. Zinc oxide actually worsens the reaction. /Pyrethroids/
Eye contamination. Some pyrethroid compounds can be very corrosive to the eyes.
Extraordinary measures should be taken to avoid eye contamination. the eye should be
treated immediately by prolonged flushing of the eye with copious amounts of clean water
or saline. If irritation persists, obtain professional ophthalmologic care. /Pyrethroids/
Other treatments. Several drugs are effective in relieving the pyrethroid neurotoxic
manifestations observed in deliberately poisoned laboratory animals, but none has been
tested in human poisonings. Therefore, neither efficacy nor safety under these
circumstances is known. Furthermore, moderate neurotoxic symptoms and signs are likely to
resolve spontaneously if they do occur. /Pyrethroids/
Animal Toxicity Studies:
Non-Human Toxicity Excerpts:
METABOLIC ACTIVATION SYSTEM WITH RAT-LIVER MICROSOME FRACTION PLUS COFACTORS (S9 MIXT)
WAS APPLIED TO CHROMOSOMAL ABERRATION TESTS IN VITRO. ALLETHRIN
WAS STRONGLY POSITIVE @ LOW DOSES ONLY WHEN ACTIVATED WITH S9 MIX, USING CHINESE HAMSTER
CELLS.
Oral or intravenous administration of allethrin
produces neurotoxic symptoms consisting of mild salivation, hyperexcitability, tremors,
and convulsions which result in death. Intracerebroventricular injection of allethrin to mouse at approx 1/9 the dose of
intravenous administration, produced qualitatively identical, but less prominent symptoms,
indicating that at least some of the symptoms may be originated in the central nervous
system.
Non-phytotoxic
In 1 yr feeding trials, rats receiving 2000 mg/kg diet showed no ill effects.
When allethrins were administered to ICR mice /at 15, 50 and 150 mg/kg/day/ during
gestation /days 7-12/ to examine maternal and embryotoxic effects, no significant adverse
effects, such as abortion or resorption of the fetus or embryo, external or skeletal
abnormalities of pups, or abnormalities in growth and organ differentiation, were observed
at the doses tested.
Allethrin in corn oil was administered daily,
by oral intubation, to pregnant albino rabbits from day 6 to day 18 of gestation at levels
of 0 mg/kg (controls - corn oil only), 215 mg/kg (low level), and 350 mg/kg (high level).
There were no indications of compound related effects among the test animals, which were
similar to the controls in appearance, behaviour, body weight gain, and food consumption;
necropsy finding were also similar. The number of implantation sites compared with the
number of ovarian corpora lutea observed was similar in the pregnant animals in control,
low-dose, and high-dose groups. The number and placement of implantation sites, the
resorption sites, the numbers of live and dead fetuses, and the fetal weights and lengths
were also similar in the control and test animals. Fetal skeletal evaluations did not
reveal any compound-related abnormalities or trends towards lesser or greater development
in the test fetuses compared with the controls. Pups, of low- and high-dose animals,
delivered naturally, were similar in appearance, external morphology, and behaviour. No
compound-related observations were found during the post-delivery period (40 days) or at
necropsy of the pups.
F344 rats (male and female) were fed diets containing d-allethrin
at 0, 125, 500, or 2000 mg/kg for 123 weeks. Reduced body weight and increased liver and
kidney weights were observed at levels exceeding 500 mg/kg and the activities of glutamic
oxaloacetic and glutamic pyruvic acid transaminase and alkaline phosphatase decreased at
these levels. Histopathological examination showed histiocytes phagocyting crystals in the
liver of animals fed levels of 500 mg/kg or more, but no oncogenic effects were observed
at any dose level. The no observed adverse effect level was 125 mg/kg, ie, 5.9 mg/kg body
weight per day (male) and 6.6 mg/kg body wt per day (female).
Two solutions of allethrin dissolved in olive
oil (10% and 50%) were prepared. One tenth ml of solution was applied to one eye of each
test rabbit. Both dosages of allethrin produced
eyelid-closure, slight conjunctival hyperemia at 10 and 30 min, respectively, after
application, and eye discharge 2 hr after application. Lacrimation was also observed in
the group treated with the 50% solution from 0.5 to 2 hr after application.
When Wistar rats were exposed to racemic allethrin
(dietary levels of 500, 1000, or 2000 mg/kg) for 80 weeks, bile duct proliferation was
seen at levels of 1000 mg/kg or more and a decrease in glutamine-oxaloacetic acid
transaminase activity was seen at 2000 mg/kg. However, no oncogenic effects were observed
at any dose level.
One half ml of a 5% olive oil solution of allethrin
was applied topically to the backs of male guinea-pigs, every other day, 10 times. Two
weeks after the last application, the animals were challenged with a similar application
of allethrin. Only a sporadic pinkish color was
observed (same degree as vehicle control) at the site of application. Histopathological
examination revealed slight lymphocytic and monocytic infiltration of the dermis in the allethrin-treated group.
Symptoms of allethrin ... intoxication are
like those from the natural pyrethrins.
Two pyrethroids, bioallethrin and
deltamethrin, affect muscarinic cholinergic receptors in the neonatal mouse brain when
given to suckling mice during the period of rapid brain growth. Such early exposure to
these pyrethroids can also lead to permanent changes in the muscarinic cholinergic
receptors and behavior in the mice as adults. In the present study, male NMRI mice were
given bioallethrin (0.7 mg), deltamethrin (0.7
mg), or a 20% fat emulsion vehicle (10 ml) per kilogram of body wt per os once daily
between the 10th and 16th postnatal day. The mice were subjected to behavioral tests upon
reaching the age of 17 days and at 4 mo. Within 1-2 wk after the behavioral tests the mice
were killed by decapitation and crude synaptosomal fractions (P2) were prepared from the
cerebral cortex, hippocampus, and striatum. The densities of muscarinic cholinergic
receptors were assayed by measuring the amounts of (3)H quinuclidinyl benzilate
specifically bound in the P2 fraction. The proportions of high affinity and low-affinity
binding sites of muscarinic cholinergic receptors were assayed in a displacement study
using (3)H quinuclidinyl benzilate/carbachol. The behavioral tests at an adult age of 4 mo
indicated a significant increase in spontaneous motor behavior in both bioallethrin
and deltamethrin treated mice. There was also a significant decrease and a tendency toward
a decrease in the density of muscarinic cholinergic receptors in the cerebral cortex in
mice receiving bioallethrin and deltamethrin,
respectively. The proportions of high affinity and low affinity binding sites of
muscarinic cholinergic receptors were not changed. This study further supports that
disturbances of the cholinergic system during rapid development in the neonatal mouse can
lead to permanent changes in cholinergic and behavioral variables in the animals as
adults.
The type I pyrethroids produce the simplest poisoning syndrome & produce sodium
tail currents with relatively short time constants. Poisoning closely resembles that
produced by DDT & involves a progressive development of fine whole-body tremor,
exaggerated startle response, incoordinated twitching of the dorsal muscles,
hyperexcitability, & death. The tremor is assoc with a large incr in metabolic rate
& leads to hyperthermia, which, with metabolic exhaustion, is the usual cause of
death. Respiration & blood pressure are well sustained but plasma noradrenaline,
lactate, & to a lesser extent adrenaline are greatly incr. /Type I Pyrethroids/
Synthetic pyrethroids are neuropoisons acting on the axons in the peripheral and
central nervous systems by interacting with sodium channels in mammals and/or insects. A
single dose produces toxic signs in mammals, such as tremors, hyperexcitability,
salivation, choreoathetosis, and paralysis. ... At near-lethal dose levels, synthetic
pyrethroids cause transient changes in the nervous system, such as axonal swelling and/or
breaks and myelin degeneration in sciatic nerves. They are not considered to cause delayed
neurotoxicity of the kind induced by some organophosphorus compounds. /Synthetic
prethroids/
Synthetic pyrethroids have been shown to be toxic for fish, aquatic arthropods, and
honeybees in laboratory tests. But, in practical usage, no serious adverse effects have
been noticed because of the low rates of application and lack of persistence in the
environment. The toxicity of synthetic pyrethroids in birds and domestic animals is low.
/Synthetic pyrethroids/
The in vitro effects of pyrethroids on the mitogenic responsiveness of murine splenic
lymphocytes to concanavalin A and lipopolysaccharide were determined. Allethrin
was the most potent inhibitor, with effective concn in the range of 1X10-6 to 1.5X10-5 M.
The results support the possibility of immune suppression by pyrethroid exposure.
The Type I poisoning syndrome or "T syndrome" is produced by esters lacking
the alpha-cyano substituent and is characterized by restlessness, incoordination,
prostration, and paralysis in the cockroach, ascompared to the rat, which exhibits such
signs as sparring and aggressive behavior, enhanced startle response, whole body tremor,
and prostration. /Pyrethroid esters lacking the alpha-cyano substituent/
Non-Human Toxicity Values:
LD50 Rat male oral 1100 mg/kg
LD50 Rat female oral 685 mg/kg
LD50 Rabbit oral 4290 mg/kg
LD50 Rat oral 700 to 960 mg/kg
LD50 Mouse skin 1200 mg/kg
LD50 Mouse ip 38 mg/kg
LD50 Rabbit skin 11,332 mg/kg
LD50 Rabbit ip 11,200 mg/kg
LD50 Quail (laboratory) oral 2030 mg/kg
Ecotoxicity Values:
LD50 MALLARD DUCK ORAL LESS THAN 2000 MG/KG, MALE, 3-4 MONTHS OLD
LC50 GAMMARUS FASCIATUS (SCUDS) 11.0 UG/L/96 HR @ 21 DEG C (95% CONFIDENCE LIMIT
8.0-15.0 UG/L), MATURE /STATIC BIOASSAY/
LC50 PTERONARCYS CALIFORNICA (STONEFLIES) 5.6 UG/L/96 HR @ 15 DEG C (95% CONFIDENCE
LIMIT 4.9-6.4 UG/L), SECOND YR CLASS /STATIC BIOASSAY/
LC50 SALMO GAIRDNERI (RAINBOW TROUT) 19.0 UG/L/96 HR @ 13 DEG C, WT 0.9 G /STATIC
BIOASSAY/
LC50 LEPOMIS MACROCHIRUS (BLUEGILL) 56.0 UG/L/96 HR @ 24 DEG C, WT 0.9 G /STATIC
BIOASSAY/
Metabolism/Pharmacokinetics:
Metabolism/Metabolites:
AFTER ADMINISTRATION OF LABELED ALLETHRIN TO
MALE RATS, THE MAJOR METABOLITES FOUND WERE ALCOHOL-ACIDS. FROM NMR AND MASS SPECTRA A
THIRD METABOLITE WAS IDENTIFIED AS ALLETHRIN
WITH ONE CYCLOPROPANE METHYL HYDROXYLATED AND OXIDATION OF THE TRANSMETHYL TO A CARBOXYL
GROUP. HYDROLYSIS PRODUCED SMALL AMT OF ALLETHROLONE AND CHRYSANTHEMUM DICARBOXYLIC ACID.
ACID- AND ALCOHOL-LABELED ALLETHRIN WAS
INCUBATED WITH ENZYME SYSTEMS FROM HOUSEFLY ABDOMEN HOMOGENATES. EACH OF THE TEN OR MORE
OBSERVED METABOLITES WAS AN ESTER, WAS MORE POLAR THAN ALLETHRIN,
& WAS FORMED BY THE MIXED-FUNCTION OXIDASE SYSTEM. THE MAJOR ALLETHRIN
METABOLITE WAS ORTHO-DEMETHYL ALLETHRIN II. ...
/IN STUDYING THE METABOLISM OF ALLETHRIN IN
HOUSEFLIES, IT WAS FOUND THAT IN/ ALLETHRIN
LABELED IN THE KETOCYCLOPENTENYL PORTION OF THE MOLECULE, A METABOLITE THAT BEHAVED AS
KETOCYCLOPENTENOL WAS ISOLATED BY PAPER CHROMATOGRAPHY. ... INVESTIGATORS USING ALLETHRIN LABELED IN CHRYSANTHEMUMIC ACID PORTION OF
MOLECULE WERE ABLE TO DETECT ONLY TRACES OF ACID IN HOUSEFLY HOMOGENATES OR EXCRETA. ...
ONLY TRACES OF UNCHANGED ALLETHRIN WERE
RECOVERABLE AND THE BULK OF THE RECOVERED MATERIAL MUST BE A DERIVATIVE OF THE INTACT
ESTER OR OF THE ACID.
Allethrin is oxidized not only at the
chrysanthemate isobutenyl moiety to the corresponding primary alcohol but also at the
allyl group to 1'-hydroxyprop-2'-enyl and 2',3'-dihydroxy-propyl derivatives, or at a
methyl group on the cyclopropyl moiety to a hydroxy derivative. Allethrin
is also converted to chrysanthemum dicarboxylic acid and allethrolone.
When allethrin was applied topically to
houseflies, chromatography indicated the presence of allethrone and chrysanthemic acid in
addition to allethrin and three unidentified
compounds.
The microsome or microsome-plus-soluble fraction prepared from rat or mouse liver
homogenate was incubated in a phosphate buffer (0.1 mol/litre, pH 7.4) for 30 min at 37
deg C with 7 or 70 ug allethrin, in the presence
or absence of NADPH. Allethrin yielded neutral
metabolites several acidic metabolites, and some other polar metabolites, when examined
using two-dimensional thin-layer chromatography.
When allethrin labelled with 14(C) in the
acid moiety or with 3H in the alcohol moiety was administered orally to male Sprague
Dawley rats at levels ranging from 1 to 5 mg/kg body weight, the radiocarbon and tritium
from the acid and alcohol labellings were eliminated in the urine (30% and 20.7%,
respectively) and feces (29% and 27%, respectively) in 48 hr. The tissue residues were not
determined. Most of the metabolites excreted in the urine were ester form metabolites
together with two hydrolysed products, chrysanthemum dicarboxylic acid and allethrolone.
The fecal metabolites were not identified. Allethrin
could have been metabolized via any of the following 5 biotransformation pathways;
hydrolysis to allethrolone and to a smaller extent chrysanthemum dicarboxylic acid
formation of the 2,3-diol from the allyl moiety, hydroxylation at the methylene position
of the allyl grouping, hydroxylation at one of the geminal dimethyl groups, and oxidation
at the trans methyl group of the isobutenyl moiety carboxylic acid.
Metabolism of the chrysanthemates (S)-bioallethrin,
cinerin I, jasmolin I, and pyrethrin I by NADPH-dependent oxidases of mouse liver
microsomes yields 13-18 metabolites in each case oxidized at the methyl, methylene, and
alkenyl substituents to form alcohols, aldehydes, carboxylic acids, epoxides, and
dihydrodiols. Rat microsomes are more specific than mouse microsomes in hydroxylating the
(E)-methyl substituent of the 2-methylpropenyl moiety compared with other molecular sites.
Metabolites in the urine of allethrin treated
rats include compounds modified in both the 2-methylpropenyl and allyl moieties as free
carboxylic acids and glucuronides. The pyrethrates cinerin II, jasmolin II, an pyrethrin
II undergo microsomal hydrolysis of the methoxycarbonyl group and oxidation of the
butenyl, pentenyl, and pentadienyl substituents of alcohols, epoxides, and dihydrodiols.
...
The metabolic pathways for the breakdown of the pyrethroids vary little between
mammalian species but vary somewhat with structure. ... Essentially, pyrethrum and allethrin are broken down mainly by oxidation of the
isobutenyl side chain of the acid moiety & of the unsaturated side chain of the
alcohol moiety with ester hydrolysis playing & important part, whereas for the other
pyrethroids ester hydrolysis predominates. /Pyrethrum and pyrethroids/
The relative resistance of mammals to the pyrethroids is almost wholly attributable to
their ability to hydrolyze the pyrethroids rapidly to their inactive acid & alcohol
components, since direct injection into the mammalian CNS leads to a susceptibility
similar to that seen in insects. Some addtl resistance of homeothermic organisms can also
be attributed to the negative temperature coefficient of action of the pyrethroids, which
are thus less toxic at mammalian body temperatures, but the major effect is metabolic.
Metabolic disposal of the pyrethroids is very rapid, which means that toxicity is high by
the iv route, moderate by slower oral absorption, & often unmeasureably low by dermal
absorption. /Pyrethroids/
FASTEST BREAKDOWN IS SEEN WITH PRIMARY ALCOHOL ESTERS OF TRANS-SUBSTITUTED ACIDS SINCE
THEY UNDERGO RAPID HYDROLYTIC & OXIDATIVE ATTACK. FOR ALL SECONDARY ALCOHOL ESTERS
& FOR PRIMARY ALCOHOL CIS-SUBSTITUTED CYCLOPROPANECARBOXYLATES, OXIDATIVE ATTACK IS
PREDOMINANT. /PYRETHROIDS/
Synthetic pyrethroids are generally metabolized in mammals through ester hydrolysis,
oxidation, and conjugation, and there is no tendency to accumulate in tissues. In the
environment, synthetic pyrethroids are fairly rapidly degraded in soil and in plants.
Ester hydrolysis and oxidation at various sites on the molecule are the major degradation
processes. /Synthetic pyrethroids/
Absorption, Distribution & Excretion:
/PYRETHROIDS/ READILY PENETRATE INSECT CUTICLE AS SHOWN BY TOPICAL LD50 TO PERIPLANETA
(COCKROACH) ... /PYRETHROIDS/
WHEN RADIOACTIVE PYRETHROID IS ADMIN ORALLY TO MAMMALS, IT IS ABSORBED FROM INTESTINAL
TRACT OF THE ANIMALS & DISTRIBUTED IN EVERY TISSUE EXAMINED. EXCRETION OF
RADIOACTIVITY IN RATS ADMIN TRANS-ISOMER: DOSAGE: 500 MG/KG; INTERVAL 20 DAYS; URINE 36%;
FECES 64%; TOTAL 100%. /PYRETHROIDS/
Pyrethrins are absorbed through intact skin when applied topically. When animals were
exposed to aerosols of pyrethrins with piperonyl butoxide being released into the air,
little or none of the combination was systemically absorbed. /Pyrethrins/
Although limited absorption may account for the low toxicity of some pyrethroids, rapid
biodegradation by mammalian liver enzymes (ester hydrolysis and oxidation) is probably the
major factor responsible. Most pyrethroid metabolites are promptly excreted, at least in
part, by the kidney. /Pyrethroids/
Mechanism of Action:
To investigate the mechanism of action of allethrin,
the ability of agents which alter neurotransmission to prevent or potentiate the effect of
convulsive doses of technical grade (15.5% cis, 84.5% trans) allethrin
was examined. Intraperitoneal pretreatment with drugs which block noradrenergic receptors
or norepinephrine synthesis such as pentobarbital, chlorpromazine, phentolamine, and
reserpine depressed the tremor induced by allethrin.
The inhibitory effect of reserpine was reversed by phenylephrine. Both the serotonergic
blocker, methysergide and the serotonin depletor, p-chlorophenylalanine potentiated the
effect of allethrin. Thus, allethrin
produces its neurotoxic responses in mice by acting on the brain and spinal levels.
Furthermore, adrenergic excitatory and serotonergic inhibitory mechanisms may be involved
in the neural pathway through which the allethrin-induced
tremor is evoked.
The interactions of natural pyrethrins and 9 pyrethroids with the nicotinic
acetylcholine (ACh) receptor/channel complex of Torpedo electronic organ membranes were
studied. None reduced (3)H-ACh binding to the receptor sites, but all inhibited
(3)H-labeled perhydrohistrionicotoxin binding to the channel sites in presence of
carbamylcholine. Allethrin inhibited binding
noncompetitively, but (3)H-labeled imipramine binding competitively, suggesting that allethrin binds to the receptor's channel sites that
bind imipramine. The pyrethroids were divided into 2 types according to their action: type
A, which included allethrin, was more potent in
inhibiting (3)H-H12-HTX binding and acted more rapidly. Type B, which included permethrin,
was less potent and their potency increased slowly with time. The high affinities that
several pyrethroids have for this nicotinic ACh receptor suggest that pyrethroids may have
for this nicotinic ACh receptor suggest that pyrethroids may have a synaptic site of
action in addition to their well known effects on the axonal channels.
The negative temperature coefficient of toxicity of allethrin
was explained in terms of repetitive firing in peripheral (sensory) nerves rather than by
nerve blockage, which had been suggested from previous in vitro studies. The elucidation
of target sites in vivo and the most useful parameter to study, ie, repetitive firing in
nerve axons, enabled the definition of a pyrethroid resistance mechanism in a major insect
pest. ...
1. Type I (permethrin and allethrin) or type
II (cypermethrin and fenvalerate) pyrethroids caused 23-37% increases in the striatal
content of the dopamine metabolite 3,4-dihydroxyphenylacetic acid. 2. Toxicity symptoms
and increases in 3,4-dihydroxyphenylacetic acid were associated with higher brain concn
for type I (2.6-5.8 ug/gm) than type II pyrethroids (0.4-0.6 ug/gm). 3. No specific
difference in the interaction between type I and II pyrethroids and the striatal
dopaminergic system were recognized.
Phosphoinositide breakdown in guinea pig cerebral cortical synaptoneurosomes induced by
the Type I pyrethroids allethrin, resmethrin,
and permethrin and the Type II pyrethroid deltamethrin and fenvalerate were investigated
with various receptor agonists as well as sodium channel blockers and agents.
Phosphoinositide breakdown was determined from inositol-phosphate formation by tritiated
inositol labeled synaptoneurosomes. All five pyrethroids dose dependently induced
phosphoinositide breakdown. Type II pyrethroids exhibited higher potency and deltamethrin
was more efficacious than the Type I pyrethroids. Five micromolar tetrodotoxin, a blocker
of voltage dependent sodium channels, partially inhibited deltamethrin (85%) and
fenvalerate (60%) responses but not allethrin or
resmethrin. Fenvalerate induced stimulation of phosphoinositide breakdown was additive
with stimulation elicited by the receptor agonists carbamylcholine (1 mM) and
norepinephrine (1000 uM) but less than additive with the sodium channel agents
batrachotoxin, pumiliotoxin-B, and scorpion venom. Allethrin
(100 uM) was less than additive with receptor agonists or sodium channel agents and
actually significantly inhibited response to scorpion venom. Effects for 100 uM allethrin with either fenvalerate or deltamethrin were
not different from allethrin alone. Ten
micromolar allethrin slightly decreased response
to 10 to 100 uM deltamethrin. The local anesthetic dibucaine, a sodium channel activation
inhibitor, completely blocked deltamethrin induced phosphoinositide breakdown but was much
less effective in inhibiting allethrin response.
It appears likely that Type-I pyrethroids induce phosphoinositide breakdown through a
mechanism other than sodium channel activation while Type-II pyrethroids act in a manner
analogous to other sodium channel agents.
The transmitter activated ion channels are known to be important target sites of a
variety of therapeutic and toxic agents. The GABA activated chloride channel has been
shown to be modulated by general anesthetics, alcohols, and the pyrethroid, cyclodiene and
lindane insecticides. The general anesthetics halothane, enflurane an isoflurane greatly
augmented the GABA activated current before desensitization took place, and suppressed it
after desensitization at clinically relevant concn equivalent to 1-2 minimum alveolar
concn. The stimulating effect appears to be a mechanism of general anesthesia. It seems
that general anesthetics have a specific affinity for the GABA receptor-channel complex.
Ethanol also augmented the GABA-activated peak chloride current with little or no effect
on the desensitized sustained current. Longer chain alcohols n-butanol, n-hexanol,
n-octanol, and n-decanol also exerted the same type of effect, with the potency and
efficacy increasing with lengthening of the carbon chain. The GABA receptor-channel
complex has also been shown to be an important target site of certain insecticides. The
type II pyrethroids deltamethrin and fenvalerate augmented the GABA activated peak
chloride current when applied concurrently with GABA, but the effect was diminished as the
pyrethroids were applied for long periods of time prior to GABA application. The latter
effect might explain the controversy in the literature regarding the pyrethroid action on
the GABA system. The type I pyrethroid allethrin
suppressed the GABA activated peak chloride current when co-applied with GABA. Both types
of pyrethroids suppressed the N-methyl-d-aspartate induced current. Lindane and the
cyclodienes dieldrin, endrin, heptachlor epoxide, and isobenzan suppressed the GABA
activated chloride current. These effects can account for the convulsant action of lindane
and the cyclodienes.
The synthetic pyrethroids delay closure of the sodium channel, resulting in a sodium
tail current that is characterized by a slow influx of sodium during the end of
depolarization. Apparently the pyrethroid molecule holds the activation gate in the open
position. Pyrethroids with an alpha-cyano group (eg, fenvalerate) produce more prolonged
sodium tail currents than do other pyrethroids (e.g., permethrin, bioresmethrin). The
former group of pyrethroids causes more cutaneous sensations than the latter. /Synthetic
pyrethroids/
Interaction with sodium channels is not the only mechanism of action proposed for the
pyrethroids. Their effects on the CNS have led various workers to suggest actions via
antagonism of gamma-aminobutyric acid (GABA)-mediated inhibition, modulation of nicotinic
cholinergic transmission, enhancement of noradrenaline release, or actions on calcium
ions. Since neurotransmitter specific pharmacological agents offer only poor or partical
protection against poisoning, it is unlikely that one of these effects represents the
primary mechanism of action of the pyrethroids, & most neurotransmitter release is
secondary to incr sodium entry. /Pyrethroids/
The symptoms of pyrethrin poisoning follow the typical pattern ... : (1) excitation,
(2) convulsions, (3) paralysis, and (4) death. The effects of pyrethrins on the insect
nervous system closely resemble those of DDT, but are apparently much less persistent.
Regular, rhythmic, and spontaneous nerve discharges have been observed in insect and
crustacean nerve-muscle preparations poisoned with pyrethrins. The primary target of
pyrethrins seems to be the ganglia of the insect central nervous system although some
pyrethrin-poisoning effect can be observed in isolated legs. /Pyrethrins/
Electrophysiologically, pyrethrins cause repetitive discharges and conduction block.
/Pyrethrins/
The interaction of a series of pyrethroid insecticides with the sodium channels in
myelinated nerve fibers of the clawed frog, Xenopus laevis, was investigated using the
voltage clamp technique. Of 11 pyrethroids, 9 insecticidally active cmpd induced a slowly
decaying sodium tail current on termination of a step depolarization, whereas the sodium
current during depolarization was hardly affected. /Pyrethroids/
Mode of action of pyrethrum & related cmpd has been studied more in insects &
in other invertebrates than in mammals. This action involves ion transport through the
membrane of nerve axons &, at least in invertebrates & lower vertebrates, it
exhibits a negative temperature coefficient. In both of these important ways & in many
details, the mode of action of pyrethrin & pyrethroids resembles that of DDT.
Esterases & mixed-function oxidase system differ in their relative importance for
metabolizing different synthetic pyrethroids. The same may be true of the constituents of
pyrethrum, depending on strain, species, & other factors. /Pyrethrins and pyrethroids/
The primary target site of pyrethroid insecticides in the vertebrate nervous system is
the sodium channel in the nerve membrane. Pyrethroids without an alpha-cyano group (allethrin, d-phenothrin, permethrin, and cismethrin)
cause a moderate prolongation of the transient increase in sodium permeability of the
nerve membrane during excitation. This results in relatively short trains of repetitive
nerve impulses in sense organs, sensory (afferent) nerve fibers, and, in effect, nerve
terminals. On the other hand the alpha-cyano pyrethroids cause a long lasting prolongation
of the transient increase in sodium permeability of the nerve membrane during excitation.
This results in long-lasting trains of repetitive impulses in sense organs and a
frequency-dependent depression of the nerve impulse in nerve fibers. The difference in
effects between permethrin and cypermethrin, which have identical molecular structures
except for the presence of an alpha-cyano group on the phenoxybenzyl alcohol, indicates
that it is this alpha-cyano group that is responsible for the long-lasting prolongation of
the sodium permeability. Since the mechanisms responsible for nerve impulse generation and
conduction are basically the same throughout the entire nervous system, pyrethroids may
also induce repetitive activity in various parts of the brain. The difference in symptoms
of poisoning by alpha-cyano pyrethroids, compared with the classical pyrethroids, is not
necessarily due to an exclusive central site of action. It may be related to the
long-lasting repetitive activity in sense organs and possibly in other parts of the
nervous system, which, in a more advance state of poisoning, may be accompanied by a
frequency-dependent depression of the nervous impulse. /Synthetic pyrethroids/
Pyrethroids also cause pronounced repetitive activity and a prolongation of the
transient increase in sodium permeability of the nerve membrane in insects and other
invertebrates. Available information indicates that the sodium channel in the nerve
membrane is also the most important target site of pyrethroids in the invertebrate nervous
system. /Synthetic pyrethroids/
Type I Pyrethroid esters /lacking the alpha-cyano substituents/ affect sodium channels
in nerve membranes, causing repetitive (sensory, motor) neuronal discharge and a prolonged
negative afterpotential, the effects being quite similar to those produced by DDT.
/Pyrethroid esters lacking the alpha-cyano substituent/
Interactions:
INSECTICIDAL ACTIVITIES OF ALLETHRIN ARE
ENHANCED BY PYRETHRIN SYNERGISTS SUCH AS PIPERONYL BUTOXIDE OR
BIS(2,3,3,3-TETRACHLOROPROPYL) ETHER, OR
N-(2-ETHYLHEXYL)-8,9,10-TRINORBORN-5-ENE-2,3-DICARBOXIMIDE.
Diazepam delayed the onset of action of deltamethrin, but not of allethrin,
in both the mouse and cockroach.
Synergists for pyrethroid /insecticidal activity/ may include the following: sesamin,
sesamolin, piperonyl-butoxide, Tropital, Sesamex, propyl-isomer, satroxan, sulfoxide,
piperonylcyclonene, MGK 264, Synepirin 500, and SKF 5254. /Pyrethroids, data derived from
table/
The mechanism of interaction of the 2 pyrethroids, allethrin
and fluvalinate, with the nicotinic acetylcholine (ACh) receptor was investigated by means
of their effects on the binding of radioligands to the Torpedo electric organ receptor and
tracer ion flux. The data suggest that allethrin
and fluvalinate bind to sites on the nicotinic ACh-receptor that are quite distinct from
the receptor site and the ionic channel sites where noncompetitive blockers eg, (3)HH12HTX
bind. Such pyrethroids may be binding to sites that normally bind Ca2+ and induce receptor
desensitization. The data imply that modulation of the nicotinic ACh-receptor in insect
ganglia may be involved in the mode of action of pyrethroids.
/Pyrethroid/ detoxification ... important in flies, may be delayed by the addition of
synergists ... organophosphates or carbamates ... to guarantee a lethal effect. ...
/Pyrethroid/
Piperonyl butoxide potentiates /insecticidal activity/ of pyrethrins by inhibiting the
hydrolytic enzymes responsible for pyrethrins' metabolism in arthropods. When piperonyl
butoxide is combined with pyrethrins, the insecticidal activity of the latter drug is
increased 2-12 times /Pyrethrins/
At dietary level of 1000 ppm pyrethrins & 10000 ppm piperonyl butoxide ...
/enlargement, margination, & cytoplasmic inclusions in liver cells of rats/ were well
developed in only 8 days, but ... were not maximal. Changes were proportional to dosage
& similar to those produced by DDT. Effects of the 2 ... were additive. /Pyrethrins/
Pharmacology:
Therapeutic Uses:
Pyrethrins with piperonyl butoxide are used for topical treatment of pediculosis(lice
infestations). Combinations of pyrethrins with piperonyl butoxide are not effective for
treatment of scabies (mite infestations). Although there are no well-controlled
comparative studies, many clinicians consider 1% lindane to be pediculicide of choice.
However, some clinicians recommend use of pyrethrins with piperonyl butoxide, esp in
infants, young children, & pregnant or lactating women ... . If used correctly, 1-3
treatments ... are usually 100% effective ... Oil based (eg, petroleum distillate)
combinations ... produce the quickest results. ... For treatment of pediculosis, enough
gel, shampoo, or solution ... should be applied to cover affected hair & adjacent
areas ... After 10 min, hair is ... washed thoroughly ... treatment should be repeated
after 7-10 days to kill any newly hatched lice. /Pyrethrins/
Interactions:
INSECTICIDAL ACTIVITIES OF ALLETHRIN ARE
ENHANCED BY PYRETHRIN SYNERGISTS SUCH AS PIPERONYL BUTOXIDE OR
BIS(2,3,3,3-TETRACHLOROPROPYL) ETHER, OR
N-(2-ETHYLHEXYL)-8,9,10-TRINORBORN-5-ENE-2,3-DICARBOXIMIDE.
Diazepam delayed the onset of action of deltamethrin, but not of allethrin,
in both the mouse and cockroach.
Synergists for pyrethroid /insecticidal activity/ may include the following: sesamin,
sesamolin, piperonyl-butoxide, Tropital, Sesamex, propyl-isomer, satroxan, sulfoxide,
piperonylcyclonene, MGK 264, Synepirin 500, and SKF 5254. /Pyrethroids, data derived from
table/
The mechanism of interaction of the 2 pyrethroids, allethrin
and fluvalinate, with the nicotinic acetylcholine (ACh) receptor was investigated by means
of their effects on the binding of radioligands to the Torpedo electric organ receptor and
tracer ion flux. The data suggest that allethrin
and fluvalinate bind to sites on the nicotinic ACh-receptor that are quite distinct from
the receptor site and the ionic channel sites where noncompetitive blockers eg, (3)HH12HTX
bind. Such pyrethroids may be binding to sites that normally bind Ca2+ and induce receptor
desensitization. The data imply that modulation of the nicotinic ACh-receptor in insect
ganglia may be involved in the mode of action of pyrethroids.
/Pyrethroid/ detoxification ... important in flies, may be delayed by the addition of
synergists ... organophosphates or carbamates ... to guarantee a lethal effect. ...
/Pyrethroid/
Piperonyl butoxide potentiates /insecticidal activity/ of pyrethrins by inhibiting the
hydrolytic enzymes responsible for pyrethrins' metabolism in arthropods. When piperonyl
butoxide is combined with pyrethrins, the insecticidal activity of the latter drug is
increased 2-12 times /Pyrethrins/
At dietary level of 1000 ppm pyrethrins & 10000 ppm piperonyl butoxide ...
/enlargement, margination, & cytoplasmic inclusions in liver cells of rats/ were well
developed in only 8 days, but ... were not maximal. Changes were proportional to dosage
& similar to those produced by DDT. Effects of the 2 ... were additive. /Pyrethrins/
Environmental Fate & Exposure:
Environmental Fate/Exposure Summary:
Allethrin's production and use as an
insecticide is expected to result in its direct release to the environment. If released to
air, a vapor pressure of 1.2X10-6 mm Hg at 21 deg C indicates allethrin
will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase
allethrin will be degraded in the atmosphere by
reaction with photochemically-produced hydroxyl radicals and ozone molecules. The
half-life for the reaction in air with hydroxyl radicals is estimated to be 1.7 hours. The
half-life for the reaction in air with ozone is estimated to be 18 minutes. The
vapor-phase reaction of allethrin with nitrate
radicals may also be an important atmospheric removal process in urban areas at night, but
the rate of this reaction is not known. Allethrin
also undergoes direct photolysis in the environment. Particulate-phase allethrin
will be removed from the atmosphere by wet and dry deposition. If released to soil, allethrin is expected to have no mobility based upon
an estimated Koc of 9,500. Volatilization from moist soil surfaces is not expected to be
an important fate process based upon an estimated Henry's Law constant of 1X10-7 atm-cu
m/mole. Allethrin is not expected to volatilize
from dry soil surfaces based upon its vapor pressure. Although biodegradation data for allethrin are not available, the pyrethroid class of
insecticides is degraded readily by environmental microorganisms and based upon its
structure, allethrin is also expected to degrade
readily. Photodegradation studies using sunlamps or natural sunlight have found
photodegradation rates of 90% in 8 hr to 11.1% in 15 min as either thin-films on glass
plates or as aqueous suspensions. If released into water, allethrin
is expected to adsorb to suspended solids and sediment based upon its estimated Koc.
Volatilization from water surfaces is not expected to be an important fate process based
upon this compound's estimated Henry's Law constant. An estimated BCF of 20 suggests the
potential for bioconcentration in aquatic organisms is low. Estimated base catalyzed
second order hydrolysis half-lives at pH 7 and 8 are 24 and 2.4 years, respectively.
Occupational exposure to allethrin may occur
through inhalation of dust particles or sprays and dermal contact with this compound at
workplaces where allethrin is produced or used,
and especially to workers applying this compound as an insecticide. (SRC)
Probable Routes of Human Exposure:
NIOSH (NOES Survey 1981-1983) has statistically estimated that 1,366 workers are
potentially exposed to allethrin in the US(1).
The NOES Survey does not include farm workers. Occupational exposure to allethrin
may occur through inhalation of dust particles or sprays and dermal contact with this
compound at workplaces where allethrin is
produced or used, and especially to workers applying this compound as an insecticide(2).
The transfer of allethrin residues from a
carpeted floor to human subjects wearing dosimeter clothing was measured(3); for gloves,
socks, shirts and tights (subjects performing standardized aerobic exercises), the
transfer coefficient ranged from 2.8 to 34.3 ug allethrin/cu
cm clothing for a period of up to 12.5 hr after applying allethrin
(via foggers) to the carpet(3); transfer rates decreased with time after application(3).
Artificial Pollution Sources:
Allethrin's production and use as an
insecticide(1) is expected to result in its direct release to the environment(SRC).
Environmental Fate:
TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of
9,500(SRC), determined from a log Kow of 4.78(2) and a regression-derived equation(3),
indicates that allethrin is expected to have no
mobility in soil(SRC). Volatilization of allethrin
from moist soil surfaces is not expected to be an important fate process(SRC) given an
estimated Henry's Law constant of 1X10-7 atm-cu m/mole(SRC), based upon its vapor
pressure, 1.2X10-6 mm Hg(4), and water solubility, 4.6 mg/l(4). Allethrin
is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of
1.2X10-6 mm Hg(4). Although biodegradation data for allethrin
are not available, the pyrethroid class of insecticides is readily degraded by
environmental microorganisms(5,6) and based upon its structure, allethrin
is also expected to readily biodegrade(5,6).
AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of
9,500(SRC), determined from a measured log Kow of 4.78(2) and a regression-derived
equation(3), indicates that allethrin is
expected to adsorb to suspended solids and sediment(SRC). Volatilization from water
surfaces is not expected(3) based upon an estimated Henry's Law constant of 1X10-7 atm-cu
m/mole(SRC), determined from its vapor pressure, 1.2X10-6 mm Hg(4), and water solubility,
4.6 mg/l(4). According to a classification scheme(5), an estimated BCF of 20(SRC), from
its log Kow(2) and a regression-derived equation(6), suggests the potential for
bioconcentration in aquatic organisms is low. Second-order hydrolysis half-lives of 24 and
2.4 years at a pH of 7 and 8, respectively, indicate hydrolysis is not expected to be an
important environmental fate process. Although biodegradation data for allethrin
are not available, the pyrethroid class of insecticides is readily degraded by
environmental microorganisms(7,8) and based upon its structure, allethrin
is also expected to readily biodegrade(7,8).
ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile
organic compounds in the atmosphere(1), allethrin,
which has a vapor pressure of 1.2X10-6 mm Hg at 21 deg C(2), will exist in both the vapor
and particulate phases in the ambient atmosphere. Vapor-phase allethrin
is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals
and ozone molecules(SRC). The half-life for the reaction in air with hydroxyl radicals is
estimated to be 1.7 hours(SRC), calculated from its rate constant of 2.2X10-10 cu
cm/molecule-sec at 25 deg C(SRC) determined using a structure estimation method(3). The
half-life for the reaction in air with ozone molecules is estimated to be 18 minutes(SRC),
calculated from its rate constant of 9.2X10-16 cu cm/molecule-sec at 25 deg C(SRC)
determined using a structure estimation method(3). The vapor-phase reaction of allethrin with nitrate radicals may be an important
atmospheric removal process in urban areas at night(4), but the rate of this reaction is
not known. Particulate-phase allethrin may be
removed from the air by wet and dry deposition(SRC).
Environmental Biodegradation:
Although environmental biodegradation data specific to allethrin
are not available, the pyrethroid class of insecticides is readily degraded by
environmental microorganisms(1,2); based upon its structure, allethrin
is also expected to readily biodegrade(1,2).
Environmental Abiotic Degradation:
ALLETHRIN DECOMP READILY WHEN SUBJECTED TO
IRRADIATION OF SUNLIGHT OR SUN LAMP TO YIELD 11-15 PRODUCTS. PHOTOCHEMICAL CHANGES
OCCURRED IN ACID MOIETY AND INVOLVED STEP-WISE OXIDN OF THE TRANS-METHYL GROUP TO THE
ALCOHOL, ALDEHYDE, CARBOXYL DERIVATIVES AND OXIDATION OF THE DOUBLE BOND TO A KETO
FUNCTION WITH SUBSEQUENT RUPTURE TO FORM TRANS-CARBONIC ACID ESTERS. OTHER ATTACKS
EFFECTED AT LEAST 6 ADDITIONAL CHANGES OF ACID MOIETY. ALCOHOL MOIETY UNDERWENT
PHOTOCHEMICAL ALTERATIONS ALSO, BUT THE REACTIONS INVOLVED WERE NOT KNOWN.
Photodecomposition of each of the four pyrethroids gave rise to 12-16 products but
little ester hydrolysis. Trans- & meso-cis-caronic acids were identified by
co-chromatography.
The rate constant for the vapor-phase reaction of allethrin
with photochemically-produced hydroxyl radicals has been estimated as 2.2X10-10 cu
cm/molecule-sec at 25 deg C(SRC) using a structure estimation method(1). This corresponds
to an atmospheric half-life of about 1.7 hours at an atmospheric concentration of 5X10+5
hydroxyl radicals per cu cm(1). The rate constant for the vapor-phase reaction of allethrin with ozone molecules has been estimated as
9.2X10-16 cu cm/molecule-sec at 25 deg C(SRC) using a structure estimation method(1). This
corresponds to an atmospheric half-life of about 18 minutes at an atmospheric
concentration of 7X10+11 ozone molecules per cu cm(2). The vapor-phase reaction of allethrin with nitrate radicals may be an important
atmospheric removal process in urban areas at night(3), but the rate of this reaction is
not known. A base-catalyzed second-order hydrolysis rate constant of 9X10-3
L/mole-sec(SRC) was estimated using a structure estimation method(4); this corresponds to
half-lives of 24 and 2.4 years at pH values of 7 and 8, respectively(4). In
photodegradation studies using a sunlamp, allethrin
in air or as a thin-film on glass, was observed to readily decompose(5); thin films on
glass underwent a 90% loss in 8 hr with part of the loss resulting from volatilization(5);
photodegradation products were measured but not specifically identified(5). Aqueous
suspensions of allethrin exposed to sunlight
experienced an 11.1% photodecomposition after only 15 min of exposure(6); addition of
chloroplasts to the suspensions photosensitized the photolysis and increase degradation
rates in sunlight(6). Addition of the pesticide trifluralin has been observed to
photostabilize allethrin(7).
Environmental Bioconcentration:
An estimated BCF of 20 was calculated for allethrin(SRC),
using a log Kow of 4.78(1) and a regression-derived equation(2). According to a
classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic
organisms is low(SRC).
Soil Adsorption/Mobility:
The Koc of allethrin is estimated as
9,500(SRC), using a measured log Kow of 4.78(1) and a regression-derived equation(2).
According to a classification scheme(3), this estimated Koc value suggests that allethrin is expected to have no mobility in soil.
Volatilization from Water/Soil:
The Henry's Law constant for allethrin is
estimated as 1X10-7 atm-cu m/mole(SRC), determined from its vapor pressure, 1.2X10-6 mm
Hg(1), and water solubility, 4.6 mg/l(1). This Henry's Law constant indicates that allethrin is expected to be essentially nonvolatile
from moist soil and water surfaces(2). Allethrin
is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of
1.2X10-6 mm Hg(1).
Effluent Concentrations:
Particulate bound allethrin was detected in
mosquito coil smoke at observed concentrations of 29.1 and 15.1 mg/g of particulate(1).
Atmospheric Concentrations:
INDOOR AIR: Indoor air concns of allethrin
were measured in a public community college cafeteria after bi-monthly applications of the
insecticide(1); avg concns were as follows after an application(1): 0.1 days after: 15-48
ng/cu m; 1 day after: 11 ng/cu m; 3 days after: 5.5 ng/cu m; 6 days after: 0.9 ng/cu m; 10
days after: 1.0 ng/cu m; 13 days after: 0.2 ng/cu m(1).
Food Survey Values:
According to compiled results of the US Food and Drug Administration's pesticide
residue monitoring programs (including the Total Diet Study) for fiscal years 1978-1986, allethrin has been detected as a pesticide residue in
American foods(1-2); the frequency of occurrence or concns of allethrin
detected were not reported(SRC).
Other Environmental Concentrations:
A study in which home foggers were used to apply allethrin
indoors determined that about 55% of the fogger contents landed on the floor(1).
Environmental Standards & Regulations:
FIFRA Requirements:
Tolerances are established for residues of the insecticide allethrin
(allyl homolog of cinerin I) from postharvest use in or on the following raw agricultural
commodities: apples, blackberries, blueberries (huckleberries), boysenberries, cherries,
crabapples, currants, dewberries, figs, gooseberries, grapes, guavas, loganberries,
mangoes, muskmelons, oranges, peaches, pears, pineapples, plums (fresh prunes),
raspberries, tomatoes, barley, corn, grain sorghum, milo, oats, rye, and wheat.
As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of
older pesticides to consider their health and environmental effects and make decisions
about their future use. Under this pesticide reregistration program, EPA examines health
and safety data for pesticide active ingredients initially registered before November 1,
1984, and determines whether they are eligible for reregistration. In addition, all
pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Allethrin is found on List A, which contains most food
use pesticides and consists of the 194 chemical cases (or 350 individual active
ingredients) for which EPA issued registration standards prior to FIFRA, as amended in
1988. Case No: 0437; Pesticide type: insecticide; Registration Standard Date: 03/24/88;
Case Status: OPP is reviewing data from the pesticide's producers regarding its human
health and/or environmental effects, or OPP is determining the pesticide's eligibility for
reregistration and developing the Reregistration Eligibility Decision (RED) document.;
Active ingredient (AI): Allethrin; AI Status:
The producers of the pesticide has made commitments to conduct the studies and pay the
fees required for reregistration, and are meeting those commitments in a timely manner.
The insecticide allethrin is exempted from
the requirement of a tolerance for residues when used before harvest in the production of
the following commodities: apples; artichokes (Jerusalem); beans; beets; beets, sugar;
broccoli; Brussels sprouts; cabbage; carrots; cauliflower; celery; chickory; Chinese
cabbage; citrus; collards; corn; endive; escarole; garlic; horseradish; kale; kohlrabi;
leeks; lettuce; mushrooms; mustard greens; onions; parsley; parsnips; peaches; pears;
peppers; potatoes; radishes; rutabagas; salsify; shallots; sorghum (milo); sorghum, grain;
spinach; sweet potatoes; tomatoes; and turnips.
Allowable Tolerances:
Tolerances are established for residues of the insecticide allethrin
(allyl homolog of cinerin I) as follows: 4 ppm from postharvest use in or on the following
raw agricultural commodities: apples, blackberries, blueberries (huckleberries),
boysenberries, cherries, crabapples, currants, dewberries, figs, gooseberries, grapes,
guavas, loganberries, mangoes, muskmelons, oranges, peaches, pears, pineapples, plums
(fresh prunes), raspberries, and tomatoes. 2 ppm from postharvest use in or on the
following grains: barley, corn, grain sorghum, milo, oats, rye, and wheat.
The insecticide allethrin is exempted from
the requirement of a tolerance for residues when used before harvest in the production of
the following commodities: apples; artichokes (Jerusalem); beans; beets; beets, sugar;
broccoli; Brussels sprouts; cabbage; carrots; cauliflower; celery; chickory; Chinese
cabbage; citrus; collards; corn; endive; escarole; garlic; horseradish; kale; kohlrabi;
leeks; lettuce; mushrooms; mustard greens; onions; parsley; parsnips; peaches; pears;
peppers; potatoes; radishes; rutabagas; salsify; shallots; sorghum (milo); sorghum, grain;
spinach; sweet potatoes; tomatoes; and turnips.
Chemical/Physical Properties:
Molecular Formula:
C19-H26-O3
Molecular Weight:
302.4
Boiling Point:
140 deg C @ 0.1 mm Hg
Melting Point:
/About/ 4 deg C
Corrosivity:
Non-corrosive
Density/Specific Gravity:
1.01 @ 20 deg C
Octanol/Water Partition Coefficient:
log Kow = 4.78
Solubilities:
Sol in kerosene, alc, carbon tetrachloride, petroleum ether, ethylene dichloride,
nitromethane
Hexane: 0.655 g/ml at 20 deg C, methanol: 72.0 ml/ml at 20 deg C
In water, 4.6 mg/l @ 25 deg C
Spectral Properties:
INDEX OF REFRACTION: 1.5070 AT 21 DEG C/D
Vapor Pressure:
1.2X10-6 mm Hg @ 21 deg C
Other Chemical/Physical Properties:
Pale yellow liquid /Technical grade/
/TECHNICAL & COMMERCIAL ALLETHRIN/ ...
CHEMICAL PROPERTIES ARE AKIN TO THOSE OF PYRETHRINS ... BUT HAVING MORE STABLE SIDE CHAIN
IT IS ... MORE PERSISTENT. ...
Chemical Safety & Handling:
DOT Emergency Guidelines:
Health: Highly toxic, may be fatal if inhaled, swallowed or absorbed through skin.
Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce
irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may
be corrosive and/or toxic and cause pollution.
Fire or explosion: Non-combustible, substance itself does not burn but may decompose
upon heating to produce corrosive and/or toxic fumes. Containers may explode when heated.
Runoff may pollute waterways.
Public safety: CALL Emergency Response Telephone Number ... . Isolate spill or leak
area immediately for at least 25 to 50 meters (80 to 160 feet) in all directions. Keep
unauthorized personnel away. Stay upwind. Keep out of low areas.
Protective clothing: Wear positive pressure self-contained breathing apparatus (SCBA).
Wear chemical protective clothing which is specifically recommended by the manufacturer.
Structural firefighters' protective clothing is recommended for fire situations ONLY; it
is not effective in spill situations.
Evacuation: ... Fire: If tank, rail car or tank truck is involved in a fire, ISOLATE
for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800
meters (1/2 mile) in all directions.
Fire: Small fires: Dry chemical, CO2 or water spray. Large fires: Water spray, fog or
regular foam. Move containers from fire area if you can do it without risk. Dike fire
control water for later disposal; do not scatter the material. Do not use straight
streams. Fire involving tanks or car/trailer loads: Fight fire from maximum distance or
use unmanned hose holders or monitor nozzles. Do not get water inside containers. Cool
containers with flooding quantities of water until well after fire is out. Withdraw
immediately in case of rising sound from venting safety devices or discoloration of tank.
ALWAYS stay away from the ends of tanks. For massive fire, use unmanned hose holders or
monitor nozzles; if this is impossible withdraw from area and let fire burn.
Spill or leak: Do not touch damaged containers or spilled material unless wearing
appropriate protective clothing. Stop leak if you can do it without risk. Prevent entry
into waterways, sewers, basements or confined areas. Cover with plastic sheet to prevent
spreading. Absorb or cover with dry earth, sand or other non-combustible material and
transfer to containers. DO NOT GET WATER INSIDE CONTAINERS.
First aid: Move victim to fresh air. Call emergency medical care. Apply artificial
respiration if victim is not breathing. Do not use mouth-to-mouth method if victim
ingested or inhaled the substance; induce artificial respiration with the aid of a pocket
mask equipped with a one-way valve or other proper respiratory medical device. Administer
oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In
case of contact with substance, immediately flush skin or eyes with running water for at
least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin.
Keep victim warm and quiet. Effects of exposure (inhalation, ingestion or skin contact) to
substance may be delayed. Ensure that medical personnel are aware of the material(s)
involved, and take precautions to protect themselves.
Skin, Eye and Respiratory Irritations:
Immediately irritating to the eye. /Pyrethrins/
The chief effect from exposure ... is skin rash particularly on moist areas of the
skin. ... May irritate the eyes.
Fire Potential:
Slight fire hazard.
Combustible
Flash Point:
GREATER THAN 140 DEG F
Fire Fighting Procedures:
Use carbon dioxide, foam, or dry chemical /on fires involving pyrethroids/. /Pyrethrum/
Fire-fighting: Self-contained breathing apparatus with a full facepiece operated in
pressure-demand or other positive-pressure mode. /Pyrethrum/
Hazardous Reactivities & Incompatibilities:
INCOMPATIBLE WITH ALKALIES.
Incompatibility: Strong oxidizers. /Pyrethrins/
... Incompatible with lime & ordinary soaps because acids & alkalies speed up
processes of hydrolysis. /Pyrethrins/
Hazardous Decomposition:
When heated to decomp it emits acrid fumes.
Protective Equipment & Clothing:
Employees should be provided with and required to use dust- and splash-proof safety
goggles where /pyrethroids/ ... may contact the eyes. /Pyrethroids/
Employees should be provided with and be required to use impervious clothing, gloves,
and face shields (eight-inch minimum). /Pyrethroids/
Wear appropriate equipment to prevent: Repeated or prolonged skin contact. /Pyrethrum
and pyrethrins/
Wear eye protection to prevent: Reasonable probability of eye contact. /Pyrethrins/
Recommendations for respirator selection. Max concn for use: 50 mg/cu m: Respirator
Classes: Any chemical cartridge respirator with organic vapor cartridge(s) in combination
with a dust, mist, and fume filter. May require eye protection. Any supplied-air
respirator. May require eye protection. Any self-contained breathing apparatus. May
require eye protection. /Pyrethrins/
Recommendations for respirator selection. Max concn for use: 125 mg/cu m: Respirator
Classes: Any supplied-air respirator operated in a continuous flow mode. May require eye
protection. Any powered, air-purifying respirator with organic vapor cartridge(s) in
combination with a dust, mist, and fume filter. May require eye protection. /Pyrethrins/
Recommendations for respirator selection. Max concn for use: 250 mg/cu m: Respirator
Classes: Any chemical cartridge respirator with a full facepiece and organic vapor
cartridge(s) in combination with a high-efficiency particulate filter. Any self-contained
breathing apparatus with a full facepiece. Any supplied-air respirator with a full
facepiece. Any powered, air-purifying respirator with a tight-fitting facepiece and
organic vapor cartridge(s) in combination with a high-efficiency particulate filter. May
require eye protection. /Pyrethrins/
Recommendations for respirator selection. Max concn for use: 5,000 mg/cu m: Respirator
Class: Any supplied-air respirator with a full facepiece and operated in a pressure-demand
or other positive pressure mode. /Pyrethrins/
Recommendations for respirator selection. Condition: Emergency or planned entry into
unknown concn or IDLH conditions: Respirator Classes: Any self-contained breathing
apparatus that has a full facepiece and is operated in a pressure-demand or other positive
pressure mode. Any supplied-air respirator with a full face piece and operated in
pressure-demand or other positive pressure mode in combination with an auxiliary
self-contained breathing apparatus operated in pressure-demand or other positive pressure
mode. /Pyrethrins/
Recommendations for respirator selection. Condition: Escape from suddenly occurring
respiratory hazards: Respirator Classes: Any air-purifying, full-facepiece respirator (gas
mask) with a chin-style, front- or back-mounted organic vapor canister having a
high-efficiency particulate filter. Any appropriate escape-type, self-contained breathing
apparatus. /Pyrethrins/
Preventive Measures:
Skin that becomes contaminated with /pyrethrum/ should be promptly washed or showered
with soap or mild detergent and water. /Pyrethrum/
Clothing contaminated with /pyrethrum/ should be placed in closed containers for
storage until provision is made for the removal of /pyrethrum/ from the clothing.
/Pyrethrum/
Respirators may be used when engineering and work practice controls are not technically
feasible, when such controls are in the process of being installed, or when they fail or
need to be supplemented. Respirators may also be used for operations which require entry
into tanks or closed vessels, and in emergency situations. /Pyrethrum/
Employees who handle /pyrethrum/ ... should wash their hands thoroughly with soap or
mild detergent and water before eating, smoking, or using toilet facilities. /Pyrethrum/
Avoid contact with skin. Keep out of any body of water. Do not contaminate water by
cleaning of equipment or disposal of waste. Do not reuse empty container. Destroy it by
perforating or crushing. /Pyrethrum/
Contact lenses should not be worn when working with this chemical. /Pyrethrins/
Workers should wash: Promptly when skin becomes contaminated. /Pyrethrins/
Work clothing should be changed daily: If it is reasonably probable that the clothing
may be contaminated. /Pyrethrins/
Remove clothing: Promptly if it is non-impervious clothing that becomes contaminated.
/Pyrethrins/
SRP: The scientific literature for the use of contact lenses in industry is
conflicting. The benefit or detrimental effects of wearing contact lenses depend not only
upon the substance, but also on factors including the form of the substance,
characteristics and duration of the exposure, the uses of other eye protection equipment,
and the hygiene of the lenses. However, there may be individual substances whose
irritating or corrosive properties are such that the wearing of contact lenses would be
harmful to the eye. In those specific cases, contact lenses should not be worn. In any
event, the usual eye protection equipment should be worn even when contact lenses are in
place.
Stability/Shelf Life:
MORE STABLE TOWARDS UV LIGHT THAN NATURAL PYRETHRINS
Decomposed by uv light.
Hydrolyzed in alkaline media.
Pyrethrins ... /are/ stable for long periods in water-based aerosols where ...
emulsifiers give neutral water systems. /Pyrethrins/
Shipment Methods and Regulations:
No person may /transport,/ offer or accept a hazardous material for transportation in
commerce unless that person is registered in conformance ... and the hazardous material is
properly classed, described, packaged, marked, labeled, and in condition for shipment as
required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./
The International Air Transport Association (IATA) Dangerous Goods Regulations are
published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and
constitute a manual of industry carrier regulations to be followed by all IATA Member
airlines when transporting hazardous materials.
The International Maritime Dangerous Goods Code lays down basic principles for
transporting hazardous chemicals. Detailed recommendations for individual substances and a
number of recommendations for good practice are included in the classes dealing with such
substances. A general index of technical names has also been compiled. This index should
always be consulted when attempting to locate the appropriate procedures to be used when
shipping any substance or article.
Storage Conditions:
Pyrethrins with piperonyl butoxide topical preparations should be stored in well-closed
containers at a temperature less than 40 deg C, preferably between 15-30 deg C.
/Pyrethrins/
Disposal Methods:
SRP: At the time of review, criteria for land treatment or burial (sanitary landfill)
disposal practices are subject to significant revision. Prior to implementing land
disposal of waste residue (including waste sludge), consult with environmental regulatory
agencies for guidance on acceptable disposal practices.
It could be ... buried in noncrop land away from water. In each of these cases it would
be better to mix the product with lime. Incineration would be an effective disposal
procedure where permitted. If an efficient incinerator is not available, the product
should be mixed with large amt of combustible material. Recommendable methods:
Incineration & landfill.
Incineration would be an effective disposal procedure where permitted. ... /Pyrethrin
products/
Occupational Exposure Standards:
Manufacturing/Use Information:
Major Uses:
For Allethrin (USEPA/OPP Pesticide Code:
004001) ACTIVE products with label matches. /SRP: Registered for use in the U.S. but
approved pesticide uses may change periodically and so federal, state and local
authorities must be consulted for currently approved uses./
INSECTICIDE FOR CONTROL OF FLIES, & MOSQUITOES IN THE HOME
... HIGHLY EFFICIENT FOR CONTROL OF LICE AFFECTING MAN.
/IT IS/ ... AS EFFECTIVE AS PYRETHRINS AGAINST HOUSE FLIES ... BUT LESS EFFECTIVE
AGAINST ROACHES AND OTHER INSECTS. ...
Control of flies, mosquitoes, ants, and other household and public health insect pests.
Often used in combination with piperonyl butoxide or other synergists, for control of
chewing and sucking insects on ornamentals, vegetables, and other crops; for household and
public insect control; for insect control in animal houses; and as an animal
ectoparasiticide.
MEDICATION
Methods of Manufacturing:
2-Allyl-3-methyl-2-cyclopenten-4-ol-1-one (allethrone) and chrysanthemum monocarboxlic
anhydride in dibutyl ether at 150-175 deg C for 3-6 hr are reacted. Upon cooling, the
solution is diluted, the chrysanthemum moncarboxlic acid byproduct is removed by
saponification, the organic phase is washed with water, and the solvent evaporated.
General Manufacturing Information:
ALLETHRIN IS ALLYL HOMOLOG OF CINERIN I,
WHICH IS ONE OF THE CONSTITUENTS OF PYRETHRUM, OLDEST KNOWN INSECTICIDE.
/Pyrethroids/ are modern synthetic insecticides similar chemically to natural
pyrethrins, but modified to increase stability in the natural environment. /Pyrethroids/
Formulations/Preparations:
USEPA/OPP Pesticide Code: 004001; Trade Names: ENT 16275, ENT 17510, FDA 1446, FMC 249,
NIA 249, Pyresin, Pynamin, Exthrin.
Aerosol dispenser; emulsifiable concentrate; dispersible powder; wettable powder; Coil
d-Allethrin is greater than/equal to 95%
(1R)-isomers and greater than/equal to 75% trans isomers
Grades: 90% technical (approx 90% pure, with 10% of isomers or related cmpd); 20%
technical, 2.5% technical.
Commercial product is a clear brownish liquid containing 75-95% of eight individual
optical geometric isomers. ...
FMC 249
CONSTITUENTS: COMMERCIAL PRODUCT: (ABUNDANCE IN %) l-ALLYLRETHRONYL
d-TRANS-CHRYSANTHEMATE 12.4; d-ALLYLRETHRONYL l-TRANS-CHRYSANTHEMATE 12.4;
d-ALLYLRETHRONYL d-TRANS-CHRYSANTHEMATE 22.8; l-ALLYLRETHRONYL l-TRANS-CHRYSANTHEMATE
22.8; l-ALLYLRETHRONYL d-CIS-CHRYSANTHEMATE 8.0; d-ALLYLRETHRONYL l-CIS-CHRYSANTHEMATE
8.0; d-ALLYLRETHRONYL d-CIS-CHRYSANTHEMATE 6.8; l-ALLYLRETHRONYL l-CIS-CHRYSANTHEMATE 6.8.
Allethrin ... supplied mainly in oil- and
water-based aerosols and sprays for use in the home and restaurants against flies and
mosquitoes. They are often formulated with a synergist such as piperonyl butoxide or MGK
264.
Pyrethroids are formulated as emulsifiable concentrates, wettable powders, granules,
and concentrates for ultra low volume application. /Pyrethroids/
Consumption Patterns:
100% AS AN INSECTICIDE FOR FLIES & MOSQUITOES IN THE HOME
Laboratory Methods:
Clinical Laboratory Methods:
Colorimetric method for allethrin residues in
milk and meat. Determination involves solvent extraction, concentration, and reaction with
highly acidic mercuric oxide-sulfuric acid reagent to produce a red color. Method reported
accurate to 0.1 ppm or 10 mg/100 g sample.
Analytic Laboratory Methods:
EAD Method 1660. The Determination of Pyrethrins and Pyrethroids in Municipal and
Industrial Wastewater by High-Performance Liquid Chromatography. Detection limit=2 ug/l.
AOAC Method 953.05. Allethrin (Technical) and
Pesticide Formulations by Titrimetric Method.
AOAC Method 973.12. D-trans Allethrin in
Pesticide Formulations by Gas Chrromatagraphic Method.
A method for the detection of allethrin ...
in mosquito coils was developed by the combination of shaking extraction /with toluene and
formic acid/ and gas chromatography . ... The recovery of allethrin
in various contents from the coils was 96.6-97.1% with a 1.2-1.5% coefficient of
variation.
Cis and trans isomers of resmethrin, permethrin, allethrin,
and ... fenvalerate were separated in less than 30 min using reversed-phase high
performance liquid chromatography . The separation procedure was applied to the detection
of residues of synthetic pyrethroids in ambient air to the preparation of pure isomers of
two of the compounds.
Five types of isomers of pyrethroids, ie, fenopathrin, resmethrin, bioresmethrin,
permethrin, phenothrin, fluvalinate, allethrin,
and bioallethrin were separated by Pirkle type
1-A chiral phase high performance liquid chromatography .
Colorimetric method for allethrin residues in
milk and meat. Determination involves solvent extraction, concentration, and reaction with
highly acidic mercuric oxide-sulfuric acid reagent to produce a red color. Method reported
accurate to 0.1 ppm or 10 mg/100 g sample.
Special References:
Special Reports:
Papadopoulou-Mourkidou E; Residue Rev 89: 179-208 (1983). A review with many references
on analysis of allethrin & other pyrethroid
insecticides.
WHO; Environmental Health Criteria 87: Allethrins - Allethrin,
d-Allethrin, Bioallethrin,
S-Bioallethrin (1989)
Miyamoto J; Environ Health Perspect 14: 15-28 (1976). Degradation, metabolism, and
toxicity of synthetic pyrethroids.
Miyamoto J, et al; Pure Appl Chem 53: 1967-2022 (1981). The chemistry, metabolism, and
residue analysis of synthetic pyrethroids.
Hutson DH; Progress in Drug Metabolism 3: 215-252 (1979). The metabolic fate of
synthetic pyrethroid insecticides in mammals.
Gammon DW; Fundam Appl Toxicol (5) 1: 9-23 (1985). Correlations between in vitro and in
vivo mechanisms of pyrethroid insecticide action.
Casida JE et al; Ann Rev Pharmacol Toxicol 23: 413-38 (1983). The mechanisms of
selective action of pyrethroid insecticide are discussed.
Synonyms and Identifiers:
Related HSDB Records:
1516 [RESMETHRIN] (Analog)
Synonyms:
(+)-ALLELRETHONYL (+)-CIS,TRANS-CHRYSANTHEMATE
**PEER REVIEWED**
D-ALLETHRIN
**PEER REVIEWED**
ALLETHRIN I
**PEER REVIEWED**
ALLETHROLONE ESTER OF CHRYSANTHEMUMMONOCARBOXYLIC ACID
**PEER REVIEWED**
ALLEVIATE
**PEER REVIEWED**
ALLYL CINERIN
**PEER REVIEWED**
ALLYL CINERIN I
**PEER REVIEWED**
D,L-2-ALLYL-4-HYDROXY-3-METHYL-2-CYCLOPENTEN-1-ONE-D,L-CHRYSANTHEMUM MONOCARBOXYLATE
**PEER REVIEWED**
2-Allyl-4-hydroxy-3-methyl-2-cyclopenten-1-one ester of chrysanthemummono- carboxylic
acid
**PEER REVIEWED**
DL-2-ALLYL-4-HYDROXY-3-METHYL-2-CYCLOPENTEN-1-ONE ESTER OF DL CIS/TRANS
2,2-DIMETHYL-3-(2-METHYLPROPENYL)-CYCLOPROPANECARBOXYLIC ACID
**PEER REVIEWED**
3-ALLYL-4-KETO-2-METHYLCYCLOPENTENYL CHRYSANTHEMUMMONOCARBOXYLATE
**PEER REVIEWED**
DL-3-ALLYL-2-METHYL-4-OXOCYCLOPENT-2-ENYL DL-CIS TRANS CHRYSANTHEMATE
**PEER REVIEWED**
3-ALLYL-2-METHYL-4-OXO-2-CYCLOPENTEN-1-YL CHRYSANTHEMATE
**PEER REVIEWED**
Allylrethronyl dl-cis-trans-chrysanthemate
**PEER REVIEWED**
BIOALTRINA
**PEER REVIEWED**
CINERIN I ALLYL HOMOLOG
**PEER REVIEWED**
CYCLOPROPANECARBOXYLIC ACID, 2,2-DIMETHYL-3-(2-METHYLPROPENYL)-, ESTER WITH
2-ALLYL-4-HYDROXY-3-METHYL-2-CYCLOPENTEN-1-ONE
**PEER REVIEWED**
CYCLOPROPANECARBOXYLIC ACID, 2,2-DIMETHYL-3-(2-METHYL-1-PROPENYL)-, 2-METHYL-
4-OXO-3-(2-PROPENYL)-2-CYCLOPENTEN-1-YL ESTER
**PEER REVIEWED**
DEPALLETHRIN
**PEER REVIEWED**
2,2-DIMETHYL-3-(2-METHYL-1-PROPENYL)CYCLOPROPANECARBOXYLIC ACID
2-METHYL-4-OXO-3-(2-PROPENYL)-2-CYCLOPENTEN-1-YL ESTER
**PEER REVIEWED**
ENT 17,510
**PEER REVIEWED**
ENT 16275
**PEER REVIEWED**
Pesticide Code: 004001
**PEER REVIEWED**
EXTHRIN
**PEER REVIEWED**
FDA 1446
**PEER REVIEWED**
FMC 249
**PEER REVIEWED**
NECARBOXYLIC ACID
**PEER REVIEWED**
NIA 249
**PEER REVIEWED**
OMS 468
**PEER REVIEWED**
PALLETHRINE (FRANCE)
**PEER REVIEWED**
PYNAMIN FORTE
**PEER REVIEWED**
PYNAMIN (JAPAN)
**PEER REVIEWED**
PYRESIN
**PEER REVIEWED**
PYRESYN
**PEER REVIEWED**
PYROCIDE
**PEER REVIEWED**
Associated Chemicals:
Bioallethrin;584-79-2
Formulations/Preparations:
USEPA/OPP Pesticide Code: 004001; Trade Names: ENT 16275, ENT 17510, FDA 1446, FMC 249,
NIA 249, Pyresin, Pynamin, Exthrin.
Aerosol dispenser; emulsifiable concentrate; dispersible powder; wettable powder; Coil
d-Allethrin is greater than/equal to 95%
(1R)-isomers and greater than/equal to 75% trans isomers
Grades: 90% technical (approx 90% pure, with 10% of isomers or related cmpd); 20%
technical, 2.5% technical.
Commercial product is a clear brownish liquid containing 75-95% of eight individual
optical geometric isomers. ...
FMC 249
CONSTITUENTS: COMMERCIAL PRODUCT: (ABUNDANCE IN %) l-ALLYLRETHRONYL
d-TRANS-CHRYSANTHEMATE 12.4; d-ALLYLRETHRONYL l-TRANS-CHRYSANTHEMATE 12.4;
d-ALLYLRETHRONYL d-TRANS-CHRYSANTHEMATE 22.8; l-ALLYLRETHRONYL l-TRANS-CHRYSANTHEMATE
22.8; l-ALLYLRETHRONYL d-CIS-CHRYSANTHEMATE 8.0; d-ALLYLRETHRONYL l-CIS-CHRYSANTHEMATE
8.0; d-ALLYLRETHRONYL d-CIS-CHRYSANTHEMATE 6.8; l-ALLYLRETHRONYL l-CIS-CHRYSANTHEMATE 6.8.
Allethrin ... supplied mainly in oil- and
water-based aerosols and sprays for use in the home and restaurants against flies and
mosquitoes. They are often formulated with a synergist such as piperonyl butoxide or MGK
264.
Pyrethroids are formulated as emulsifiable concentrates, wettable powders, granules,
and concentrates for ultra low volume application. /Pyrethroids/
Shipping Name/ Number DOT/UN/NA/IMO:
UN 2588; Pesticide, solid, toxic, not otherwise specified
UN 2902; Pesticide, liquid, toxic, not otherwise specified
UN 2903; Pesticide, liquid, toxic, flammable, not otherwise specified, flash point
between 23 deg C and 61 deg C
UN 3021; Pesticide, liquid, flammable, toxic, not otherwise specified, flash point less
than 23 deg C
IMO 3.2; Pesticide, liquid, toxic, flammable, not otherwise specified, flash point
between 23 deg C and 61 deg C
IMO 6.1; Pesticide, solid or liquid, toxic, not otherwise specified; Pesticides,
liquid, liquid, toxic, flammable, not otherwise specified, flash point between 23 deg C
and 61 deg C
Standard Transportation Number:
49 411 12; Allethrin
RTECS Number:
NIOSH/GZ1925000
Administrative Information:
Hazardous Substances Databank Number: 1511
Last Revision Date: 20011010
Last Review Date: Reviewed by SRP on 5/10/2001
Update History:
Complete Update on 10/10/2001, 55 fields added/edited/deleted.
Field Update on 08/08/2001, 1 field added/edited/deleted.
Field Update on 05/16/2001, 1 field added/edited/deleted.
Complete Update on 09/12/2000, 1 field added/edited/deleted.
Complete Update on 06/12/2000, 1 field added/edited/deleted.
Complete Update on 03/09/2000, 1 field added/edited/deleted.
Complete Update on 02/08/2000, 1 field added/edited/deleted.
Complete Update on 02/02/2000, 1 field added/edited/deleted.
Complete Update on 11/18/1999, 1 field added/edited/deleted.
Complete Update on 09/21/1999, 1 field added/edited/deleted.
Complete Update on 08/26/1999, 1 field added/edited/deleted.
Complete Update on 06/02/1998, 1 field added/edited/deleted.
Complete Update on 03/16/1998, 6 fields added/edited/deleted.
Field Update on 10/23/1997, 1 field added/edited/deleted.
Field Update on 05/08/1997, 1 field added/edited/deleted.
Field Update on 05/01/1997, 2 fields added/edited/deleted.
Complete Update on 10/13/1996, 1 field added/edited/deleted.
Complete Update on 05/10/1996, 1 field added/edited/deleted.
Complete Update on 01/21/1996, 1 field added/edited/deleted.
Complete Update on 12/28/1994, 1 field added/edited/deleted.
Complete Update on 03/25/1994, 1 field added/edited/deleted.
Complete Update on 03/01/1994, 65 fields added/edited/deleted.
Field update on 12/20/1992, 1 field added/edited/deleted.
Complete Update on 08/05/1991, 1 field added/edited/deleted.
Field update on 11/09/1990, 1 field added/edited/deleted.
Complete Update on 10/02/1990, 2 fields added/edited/deleted.
Field Update on 05/14/1990, 1 field added/edited/deleted.
Field Update on 05/05/1989, 1 field added/edited/deleted.
Field Update on 05/12/1988, 1 fields added/edited/deleted.
Complete Update on 02/25/1988, 58 fields added/edited/deleted.
Complete Update on 11/08/1985
Record Length: 130402
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