WORLD HEALTH ORGANIZATION FOOD AND AGRICULTURE
ORGANIZATION
ORGANISATION MONDIALE DE LA SANTE ORGANISATION POUR L'ALIMENTATION
ET L'AGRICULTURE
VBC/DS/82.52 Rev.1
ORIGINAL: ENGLISH
DATA SHEETS ON PESTICIDES No. 52
BENDIOCARB
It must be noted that the issue of a Data Sheet for a
particular pesticide does not imply endorsement of the pesticide by
WHO or FAO for any particular use, or exclude its use for other
purposes not stated. While the information provided is believed to
be accurate according to data available at the time when the sheet
was compiled, neither WHO nor FAO are responsible for any errors or
omissions, or any consequences therefrom.
The issue of this document does Ce document ne constitue pas une
not constitute formal publication. Il ne doit faire
publication. It should not be l'objet d'aucun compte rendu ou
reviewed, abstracted or quoted résumé ni d'aucune citation sans
without the agreement of the l'autorisation de l'Organisation
Food and Agriculture des Nations Unies pour
Organization of the United l'Alimentation et l'Agriculture
Nations or of the World Health ou de l'Organisation Mondiale de
Organization. la Santé.
CLASSIFICATION:
Primary use: Insecticide
Secondary use: Molluscicide, Nematicide
Chemical group: Carbamate
Date issued:
1. GENERAL INFORMATION
1.1 COMMON NAME:
Bendiocarb (BSI, ISO)
1.1.1 Identity:
IUPAC: 2,3-isopropylidene-dioxyphenyl methyl carbamate
No. 1: Carbamic acid, methyl, 2,3-(dimethylmethylenedioxy)
phenyl ester
Reg. No.: 22781-23-3
Molecular formula: C11H13NO4 Molecular weight: 223.25
Structural formula:
1.1.2 Synonyms:
Ent-27695; FicamR; GarvoxR; MultamatR; NC 6897; Niomil
3GR; OMS 1394; SeedoxR; TatooR; TurcamR
1.2 SYNOPSIS:
Bendiocarb is a broad spectrum, carbamate pesticide; a fast
acting anti-cholinesterase agent with effective contact and stomach
action. It does not emit toxic vapours at normal working
temperatures. Moderately toxic to mammals, it is rapidly metabolized
with immediate loss of toxicity. Bendiocarb is a weak plant systemic
with excellent residual and knockdown properties.
1.3 SELECTED PROPERTIES
1.3.1 Physical properties
The pure compound is a white crystalline solid with a melting
point of 132°C. Bendiocarb is an odourless and non-corrosive
compound.
1.3.2 Solubility
(25°C) 0.04 g/1 water
0.35 g/1 hexane
0.30 g/1 kerosine
10.0 g/1 trichloroethylene
10.0 g/1 O-xylene
40.0 g/1 benzene
40.0 g/1 ethanol
200.0 g/1 acetone
200.0 g/1 chloroform
200.0 g/1 dichloromethane
200.0 g/1 dioxane
300.0 g/1 glycerol
1.3.3 Stability
Formulated material (80%) is stable at temperatures below 40°C.
In aqueous solution at 25°C the half-life is 48 days at ph 5; 81
hours at ph 7; and 45 minutes at ph 9. Under ph 5 bendiocarb slowly
degrades to pyrogallol and acetone. On non-absorptive surfaces and
at low humidity it resists oxidation. It undergoes photo-oxidation
in direct sunlight.
1.3.4 Vapour pressure
0.667 x 10-6 kPa (5 x 10-6 mmHg) at 25°C.
1.4 AGRICULTURE, HORTICULTURE AND FORESTRY
1.4.1 Common formulations
Wettable powders (800, 500 and 200 g a.i./kg); granules for
soil and turf treatment (30, 50 and 100 g a.i./kg); dust (10 g
a.i./kg); suspension concentrate (500 g a.i./1) for spray or seed
treatments; suspension in oil for ULV application (250 g a.i./1;
residual sprays, paint on and granular preparations with bait.
1.4.2 Susceptible pests
Bendiocarb is effective against a wide range of soil, foliar
and stored product pests and ectoparasites of domestic animals. The
pests controlled include insects and other arthropods.
1.4.3 Use pattern
Bendiocarb may be applied as a soil treatment (300-2000 g
a.i./ha); as a seed treatment (1-10 g a.i./kg); as a residual spray
(100-1000 g a.i./ha); and, as a ULV spray (50-500 g a.i.,/ha).
1.4.4 Unintended effects
Bendiocarb is toxic to some beneficial organisms such as bees
and predators of plant pests.
1.5 PUBLIC HEALTH PROGRAMMES
1.5.1 Common formulations
See paragraph 1.4.1 above.
1.5.2 Pests mainly controlled
Bendiocarb is effective against a wide range of nuisance and
disease vector pests; ants, bed bugs, mosquitos, cockroaches,
domestic flies, fleas, lice (with ovicidal effects), millipedes,
scorpions, spiders, wasps, and other arthropods, molluscs and
nematodes. (Some carbamate-resistant cockroach strains may be
resistant to bendiocarb on a very limited scale.)
1.5.3 Use pattern
The 80% WP should be applied by professional applicators, it
should not be directly applied to humans or food stuffs. It may be
used safely in houses, public buildings (restaurants, hotels,
hospitals and schools); in industrial buildings; and in aircraft and
other craft. Provided the manufacturer's instructions are followed
and high pressure sprays are avoided, there is little risk of
contaminating people, food, or food utensils.
1.6 HOUSEHOLD USE
Bendiocarb is available in less concentrated formulations
suitable for home use as in section 1.5 above, and in aerosols,
ready-to-use liquids, dusts, etc.
2. TOXICOLOGY AND RISKS
2.1 TOXICOLOGY - MAMMALS
2.1.1 Absorption route
Bendiocarb may be absorbed from the gastrointestinal tract or
to a limited extent through the intact skin. Low vapour pressure
makes inhalation unlikely except from airborne spray mist.
2.1.2 Mode of action
Bendiocarb acts through inhibition of cholinesterase activity
which is rapidly reversible, the half-life of the inhibited enzyme
is approximately 30 minutes.
2.1.3 Excretion products
Bendiocarb is readily conjugated and metabolized by liver
microsome enzymes, it is rapidly excreted, mainly as sulfate and
beta-glucuronide conjugates of the phenol derivative.
2.1.4 Toxicity, single dose
Oral LD50: Rat (M) 40-156 mg/kg b.w. (unformulated
compound)
143-179 mg/kg b.w. (80% a.i. water
dispersable powder)
Dermal LD50: Rat (M), > 566 mg/kg b.w. (unformulated
compound)
> 1000 mg/kg b.w. (80% a.i. liquid
formulation)
2.1.5 Toxicity, repeated doses
Oral: There was no evidence of any treatment-related effect
in hamsters fed diets containing up to 500 ppm bendiocarb for at
least 30 days. This information was supplied by the manufacturing
company.
Dermal: In a 21-day dermal toxicity study in rats treated
with a 40% aqueous suspension of the 80% wettable powder formulation
at up to 800 mg a.i./kg, no macroscopic pathology or histological
evidence of dermal irritation was detected and no treatment-related
mortality occurred. This information was supplied by the
manufacturing company.
Inhalation: No signs of toxicity nor cholinesterase
inhibition were observed in cats exposed for 33 days in a room
treated with bendiocarb (200 mg/m2).
Cumulation of compound: Bendiocarb is non-cumulative in
mammalian tissues.
Cumulation of effect: No evidence of cumulative toxicity was
found in rat and dog 90-day dietary studies.
2.1.6 Dietary studies
Short-term: See 2.1.5 above. No lasting signs of toxicity
were reported in the above-mentioned 90-day studies.
Long-term: Two-year feeding studies with bendiocarb in rats
and dogs indicate that the principal treatment-related effects
resulted from inhibition of cholinesterase activity. In the dog
comprehensive histopathological examination showed no abnormality
associated with the treatment and a no-effect level of 20 ppm (0.6-
0.7 (mg/kg b.w.)/day) was established. In the rat the no-effect
level was 10 ppm (0.34-0.42 (mg/kg b.w.)/day). (See also 2.1.7
below.) This information was supplied by the manufacturing company.
2.1.7 Supplementary studies of toxicity:1
Carcinogenicity: In a two-year chronic oral and
carcinogenicity study in rats dietary levels of up to 200 ppm were
without effects on the tumour profile. A carcinogenicity study in
mice at levels of up to 1250 ppm indicated no treatment-related
histopathological alterations in any tissues.
Teratogenicity: Bendiocarb was not found to be teratogenic in
either the rat or the rabbit.
Mutagenicity: No evidence of mutagenic potential was found in
a mitotic non-disjunction study on Aspergillus nidulous nor in two
microbial assay studies using Bacillus subtilis and Salmonella
typhimurium strains. In a dominant lethal study in rats there was
no indication that bendiocarb produced any dominant lethal mutations
in the male germ cells.1
Reproduction: Various reproduction studies indicated that
bendiocarb has no adverse effects upon fertility or reproductive
function. This information was supplied by the manufacturing
company.
Neurotoxicity: Bendiocarb shows no irreversible or delayed
neurotoxic effects.1
1 This information was supplied by the manufacturing company.
Other: Technical bendiocarb and its commercial formulations
are not skin irritants. Contamination of the eye with technical or
formulated bendiocarb may cause temporary miosis and no more than
mild, temporary irritation.1
2.1.8 Modification of toxicity
No published information available.
2.2 TOXICOLOGY - MAN
2.2.1 Absorption
The dermal route is the main route of absorption, and
inhalation of dust or fine spray mist may also be possible routes.
2.2.2 Dangerous doses
The threshold dose for blood cholinesterase inhibition and mild
symptoms lies between 0.15 and 0.20 mg a.i./kg, for the oral route,
the latter dosage having been rapidly followed by mild vertigo,
nausea and sweating. Regression of these effects was advanced 0.5
hours after dosing and complete within 4 hours. Repeated ingestion
of 0.1 mg a.i./kg at hourly intervals was without symptoms. This
information was supplied by the manufacturing company.
2.2.3 Observations on occupationally exposed workers
The safety of bendiocarb when used as a residual mosquito
adulticide has been evaluated in both Iran and Indonesia - the
latter trial being undertaken in conjunction with the WHO Vector
Biology and Control Research Unit. Both studies were organized along
the lines of a WMO expanded Stage V evaluation programme. Very few
spraymen reported any adverse effects and where such effects were
reported the symptoms were both mild and transient. No complaints
were made by the villagers. This information was supplied by the
manufacturing company.
2.2.4 Observations on exposure of the general public
No information available. The public should not be exposed to
hazardous amounts of bendiocarb due to its poor persistence in plant
and animal tissues and provided proper treatment precautions are
followed.
1 This information was supplied by the manufacturing company.
2.2.5 Observations on volunteers
Oral administration of bendiocarb to human volunteers showed
that man and the rat are equisensitive to the pesticide. The onset
of signs of cholinesterase inhibition and the recovery from the
toxic effects were both very rapid.
2.2.6 Reported mishaps
No cases of bronchospasm due to inhalation of bendiocarb have
been reported, nor has any other specific localized response to
bendiocarb contamination. There have been no confirmed cases of
dermal irritancy, allergic response or hypersensitivity of any type
due to bendiocarb or its formulations during development and
commercial use. Three cases of deliberate poisoning by ingestion are
known, two were fatal. One accidental poisoning by ingestion,
possibly from a contaminated drinking-mug, occurred during a spray
programme in Indonesia in 1981. This information was supplied by the
manufacturing company.
2.3 TOXICITY - NON-MAMMALIAN SPECIES
2.3.1 Fish
Bendiocarb is toxic to fish. The range of LC50 for several
species is 0.7-1.76 mg a.i./1.
2.3.2 Birds
Bendiocarb is toxic to birds, it does not affect the
reproductive performance of avian species. This information was
supplied by the manufacturing company.
Oral LD50: Mallard duck, 3.1 mg a.i./kg b.w.
Bobwhite quail, 19.0 mg a.i./kg b.w.
Japanese quail, 16.0 mg a.i./kg b.w.
Domestic hen, 137.0 mg a.i./kg b.w.
2.3.3 Other species
Bendiocarb is very toxic to bees.
3. FOR REGULATORY AUTHORITIES - RECOMMENDATIONS ON REGULATION
OF COMPOUND
3.1 COMMENDED RESTRICTIONS ON AVAILABILITY
(For definition of categories, see the Introduction to Data Sheets) - All available liquid formulations are in Category 3.
Solid formulations over 10%, Category 3
Other solid formulations, Category 4
3.2 TRANSPORTATION AND STORAGE
Formulations in Categories 3 and 4: Should be transported or
stored in clearly labelled rigid and leakproof containers and away
from containers of food and drink. Storage should be under lock and
key and secure from access by unauthorized persons and children.
3.3 HANDLING
Formulations in Categories 3 and 4: Protective clothing (see
part 4) should be provided for those handling concentrates. Adequate
washing facilities should be available close at hand. Eating,
drinking and smoking should be prohibited during handling and before
washing after handling.
3.4 DISPOSAL AND/OR DECONTAMINATION OF CONTAINER
Container must be either burned or crushed and buried below
topsoil. Care must be taken to avoid subsequent contamination of
water sources. Containers may be decontaminated (for method see
paragraph 4.3 in part 4). Decontaminated containers should not be
used for food and drink.
3.5 SELECTION, TRAINING AND MEDICAL SUPERVISION OF WORKERS
Formulations in Categories 3 and 4: Pre-employment medical
examination for workers desirable. Workers suffering from active
hepatic or renal disease should be excluded from contact. Training
for workers in techniques to avoid contact essential.
3.6 ADDITIONAL REGULATIONS RECOMMENDED IF DISTRIBUTED BY AIRCRAFT
All formulations - Pilot and loaders should have special
training in application methods and early symptoms of poisoning.
Flagmen, if used, should wear overalls and be located well away from
the dropping zone.
3.7 LABELLING
Formulations in Categories 3 and 4 - Minimum cautionary
statement - "WARNING - POISON" (skull and cross-bones insignia).
Bendiocarb is a carbamate compound which inhibits cholinesterase. It
is of moderate toxicity. Avoid contact with the skin, inhalation of
dust or spray, or swallowing. Wear gloves, and clean protective
clothing, when handling this material, and a respirator when
handling concentrates. Bathe immediately after work. Ensure that
containers are stored under lock and key. Empty containers must be
disposed of in such a way as to prevent all possibility of
accidental contact with them. Keep the material out of reach of
children and well away from foodstuffs, animal feed and their
containers.
In case of contact, immediately remove contaminated clothing
and wash the skin thoroughly with soap and water; for eyes, flush
with water for 15 minutes.
If poisoning occurs, call a physician. Atropine is a specific
antidote, repeated doses may be necessary. Artificial respiration
also may be needed.
3.8 RESIDUES IN FOOD
Maximum residue levels - Maximum residue levels have not yet
been recommended by the Joint FAO/WHO Meeting on Pesticide Residues
(it is on the 1982 agenda).
4. PREVENTION OF POISONING IN MAN AND EMERGENCY AID
4.1 PRECAUTIONS IN USE
4.1.1 General
Bendiocarb is a carbamate insecticide of moderate toxicity
which is quickly metabolized and therefore acts only as an acute
poison. It can be absorbed by inhalation of dust and also to some
extent through the intact skin. It is important that concentrated
formulations be washed immediately from the skin and eyes.
4.1.2 Manufacture and formulation
T.L.V., 0.2 mg/m3; STEL, 0.6 mg/m3. Formulation should not
be attempted without advice from the manufacturer. Although
volatility is low, vapour and dusts should be controlled preferably
by mechanical means. Protective equipment for the skin and
respiratory protection is usually necessary.
4.1.3 Mixers and applicators
When opening the container and when mixing, care should be
taken to avoid contact with the mouth and eyes. If necessary a
facial visor and gloves should be worn. Mixing, if not mechanical,
should always be carried out with a paddle of appropriate length.
The applicator should avoid working in spray mists and avoid contact
with mouth. Splashes must be washed immediately from the skin or
eyes with large quantities of water. Before eating, drinking or
smoking, hands and other exposed skin should be washed.
4.1.4 Other associated workers (including flagmen in aerial
operations)
Persons exposed to bendiocarb and associated with its
application should observe the precautions described in 4.1.3 under
"Mixers and applicators".
4.1.5 Other populations likely to be affected
With correct use in agriculture and public health, the general
population should not be exposed to hazardous amounts of bendiocarb.
4.2 ENTRY OF PERSONS INTO TREATED AREAS
Unprotected persons should be kept out of treated areas until
the spray solution is dry.
4.3 DECONTAMINATION OF SPILLAGE AND CONTAINERS
Residues in containers should be emptied in diluted form into a
deep pit taking care to avoid ground waters. The empty containers
may be decontaminated by rinsing two or three times with water and
scrubbing the sides. An additional rinse should be carried out with
5% sodium hydroxide solution which should remain in a container
overnight. Impermeable gauntlets should be worn during this work and
a soakage pit should be provided for the rinsings. Decontaminated
containers should not be used for food and drink.
Spillage of bendiocarb and its formulations should be removed
by washing with 5% sodium hydroxide solution and then rinsing with
large quantities of water.
4.4 EMERGENCY AID
4.4.1 Early symptoms of poisoning
Early symptoms may include excessive sweating, headache,
weakness, giddiness, nausea, vomiting, stomach pains, salivation,
tightness of the chest, blurred vision, slurred speech and muscle
twitching.
4.4.2 Treatment before person is seen by a physician if these
symptoms appear following exposure
The person should stop work immediately, remove contaminated
clothing, wash the affected skin with soap and water. If swallowed,
vomiting should be induced if the person is conscious.
5. FOR MEDICAL AND LABORATORY PERSONNEL
5.1 MEDICAL DIAGNOSIS AND TREATMENT IN CASES OF POISONING
5.1.1 General information
Bendiocarb is a carbamate insecticide of moderate toxicity. It
is absorbed from the gastrointestinal tract and by inhalation, and
only to a limited extent through the intact skin. Its mode of action
is by reversibly inhibiting acetyl cholinesterase. Erythrocyte
cholinesterase is more inhibited than plasma cholinesterase.
Symptoms of poisoning are short lasting and in the case of
occupational overexposure occur without delay and at doses well
below the fatal dose. Because of its rapid metabolism and excretion
it does not accumulate in the tissues.
5.1.2 Symptoms and signs
Symptoms of poisoning include excessive sweating, headache,
chest tightness, giddiness, nausea, vomiting, stomach pains,
salivation, blurred vision, slurred speech and muscle twitching.
5.1.3 Laboratory
Because bendiocarb is a reversible inhibitor of cholinesterase,
measurements of cholinesterase activity should be made by a method
which minimizes the reactivation of inhibited enzyme. Erythrocyte
cholinesterase determination is more informative than measuring
either plasma or whole blood cholinesterase, but the enzyme will
only be inhibited for a short time (few hours) after exposure. The
presence of metabolites of bendiocarb in urine is also indicative of
exposure.
5.1.4 Treatment
If the pesticide has been ingested, unless the patient is
vomiting, rapid gastric lavage should be performed using 5% sodium
bicarbonate, if available. For skin contact, the skin should be
washed with soap and water. If the compound has entered the eyes
they should be washed with isotonic saline or water. Since the
symptoms of poisoning with bendiocarb are of short duration atropine
treatment is usually not necessary by the time the patient reaches a
place where this antidote is available. Where there are manifest
symptoms, 1-2 mg of atropine sulfate (adult dose) may be given
intramuscularly or even intravenously and repeated as necessary.
Care should be taken to avoid overdosage of atropine, especially
when treating children. In extreme cases, if the patient is
unconscious or is in respiratory distress, oxygen may be required.
Provide patient support as required, including: suction of
secretions, maintenance of airways, i.v. fluids p.r.n. and bladder
catheterization. Pralidoxime has been shown to be ineffective in
bendiocarb poisoning.
5.1.5 Prognosis
If the acute toxic effect is survived, the chances of complete
recovery are very good.
5.1.6 References of previously reported cases
No information
5.2 SURVEILLANCE TESTS
Due to the rapid reactivation of inhibited enzyme,
determination of blood cholinesterase level is of no value in
determining when workers should be withdrawn to prevent
overexposure. Minor complaints, such as headache and nausea, cause
the worker to stop work and thus prevent further exposure. The
worker quickly recovers, particularly if appropriate decontamination
procedures are followed.
5.3 LABORATORY METHODS
5.3.1 Detection and assay of compound and residues
Whiteoak, R. J. et al. (1978) Anal. Methods Pestic. Plant
Growth Regul., 10, 3-17. Behner, J. M. et al. (1980) J. Assoc.
Off. Anal. Chem., 43(1), 47-48.
5.3.2 Other tests in cases of poisoning
Cholinesterase levels in blood are unreliable as a routine test
to detect poisoning by bendiocarb. However, shortly after
absorption, inhibition of erythrocyte cholinesterase may be
demonstrated by an appropriate method. In plasma: Ellman, G. L. et
al. (1961) Biochem. Pharmacol., 7, 88-95. In whole blood:
Fleischer, J. et al. (1956) Arch. Indust. Hyg., 14, 510; Wilhelm,
K. et al. (1973), Bull. Wld Hlth Org., 48, 235-238.
Note: This data sheet was drafted in the Bureau of Chemical
Standards, Environmental Health Directorate, Health and
Welfare, Canada, and subsequently underwent medical,
scientific, and industrial review.