WORLD HEALTH ORGANIZATION FOOD AND AGRICULTURE
ORGANIZATION
ORGANISATION MONDIALE DE LA SANTE ORGANISATION POUR L'ALIMENTATION
ET L'AGRICULTURE
VBC/DS/77.22
ORIGINAL: ENGLISH
DATA SHEETS ON PESTICIDES No. 22
December 1976
FENTIN COMPOUNDS
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.
Part 1. General information
CLASSIFICATION:
Primary use: Fungicide
Secondary uses: Molluscicide
Chemical group: Organotin compounds
Data sheet No.: 22
Date issued: December 1976
1.1 COMMON NAME: Fentins
Identity: (i) Triphenyltin acetate
(ii) Triphenyltin chloride
(iii)Triphenyltin hydroxide
Synonyms: Local synonyms
Triphenyltins
1.2 SYNOPSIS:
Moderately toxic organotin compounds of very similar properties
which are slightly cumulative in body tissues and whose target organ
is probably the CNS.
1.3 SELECTED PROPERTIES
1.3.1 Physical characteristics:
All three compounds are white, odourless crystalline solids.
m.p. acetate 124-125°C Purity technical product 94%
m.p. chloride 106°C Purity technical product 94%
m.p. hydroxide 118-120°C Purity technical product 95%
1.3.2 Solubility:
water 20°C organic solvents
acetate 28 ppm low
chloride 40 ppm moderate
hydroxide 8 ppm moderate
1.3.3 Stability:
Acetate - stable in normal conditionsin dry air, at 150°C. 15%
decomposes within three hours, hydrolyses inwater almost completely
in 8 hours at 20°C.
Chloride - stable when stored in the dark in dry air. Hydrolyses to
the hydroxide in water.
Hydroxide - stable at room temperature. Decomposes on heating above
60°C.
1.3.4 Vapour pressure:
(volatility) Acetate, very low at 1.33 x 10-6 mm Hg at 30°C.
1.4 AGRICULTURE, HORTICULTURE AND FORESTRY
1.4.1 Common formulations
Wettable powders varying from 20% to 60%.
1.4.2 Pests mainly controlled
Potato blight, leaf spot on sugar beet and celery. Algal control on
paddy rice. Has an anti-feeding action on caterpillars - see
Meisner, J. & Ascher, K. R. S., Pflanzenkr 1965, 72, 458.
1.4.3 Use pattern
Acetate used at 260 g/ha a.i.
Hydroxide 280-330 g/ha a.i. against potato blight
Hydroxide 330-400 g/ha a.i. on sugar beet
Hydroxide 220-440 g/ha a.i. on rice
Hydroxide 1100 g/ha a.i. against coffee berry disease
1.4.4 Unintended effects
Can irritate skin, eyes, and nose.
Acetate can be phytotoxic to vines, hops, fruit, ornamentals and
glasshouse crops.
1.5 PUBLIC HEALTH PROGRAMMES
No recommended use.
1.6 HOUSEHOLD USE
Non-systemic fungicides for ornamental and glass-house plants.
Care should be taken with the acetate which may be phytotoxic to
ornamentals (see unintended effects).
Part 2. Toxicology and risks
2.1 TOXICOLOGY - MAMMALS
2.1.1 Absorption route:
absorbed through the skin and from the gastrointestinal tract.
2.1.2 Mode of action:
not entirely clear. They strongly inhibit oxidative phosphorylation
(and increase the permeability of mitochondrial membranes to K+,
Na+, C1-, malate, citrate and fumarate ions). The target organ
for toxicity is probably the CNS.
2.1.3 Excretion products:
Mainly excreted in the faeces with small amounts in the urine; it is
possible that the phenyl groups are removed by gut bacteria in the
rat as has been suggested for triphenyl lead.
2.1.4 Toxicity, single dose:
(a) acetate: oral LD50 rat (M) 136 mg/kg
rat (F) 491 mg/kg
chloride: oral LD50 rat (F) 135 mg/kg
hydroxide: oral LD50 rat (M) 240 mg/kg
rat (F) 360 mg/kg
(b) acetate: dermal LD50 guinea pig approximately 180 mg/kg
(c) most susceptible species
acetate: guinea pig (M) oral LD50 21 mg/kg
hydroxide: guinea pig (M) oral LD50 27 mg/kg
2.1.5 Toxicity; repeated doses:
Oral: Over a period of 41 days groups of 10 male and female rats
were given 28 doses of fentin chloride at 6, 12.5, 25 and 50 mg/kg.
Apart from a slight decrease in weight of the females at 12.5 mg/kg,
no effect was observed at this dose or at 6 mg/kg. However, at 25
and 50 mg/kg there was a dose related increase in mortality.
Groups of 10 or 20 rats were given 5, 20, 50 or 100 ppm of
fentin hydroxide in their diet for 20 days. Food intake and body
weight was decreased. Mortalities were 9 out of 10 at 100 ppm; 9 out
of 20 at 50 ppm and 1 out of 20 at both 20 and 5 ppm.
Inhalation: No information.
Cumulation of compound: Fentin compound can accumulate in animal
tissues; the half life is thought to be approximately 50 days in the
guinea pig.
Cumulation of effect: There are three main cumulative effects
(a) effects on testes and ovaries
(b) effects on immunological response and lymphatic system
(c) oedema of the spinal cord and brain.
2.1.6 Dietary studies
Short-term and long-term (see table).
2.1.7 Supplementary studies of toxicity
Carcinogenicity:
Triphenyltin acetate has been tested for carcinogenicity on mice.
After oral dosing of 0.464 mg/kg in 0.5% gelatin initially to mice
from seven to 28 days of age followed by 1206 ppm in the diet for 18
months, there was no significant increase in rumour incidence.
(However, since the number of animals tested was relatively small
and there was a slightly increased rumour incidence (though the
level of significance was less than 0.02) it has some priority for
further testing.)
Teratogenicity:
No reported teratogenic effects. However, there are reports of
effects on the reproductive organs as shown in the table of dietary
experiments.
Mutagenicity:
No information available.
2.1.8 Modifications of toxicity
No information available.
2.2 TOXICOLOGY - MAN
2.2.1 Absorption
May be absorbed from the gastrointestinal tract, by inhalation and
through the intact skin.
2.2.2 Dangerous doses
Single: Not known.
Repeated: No information.
2.2.3 Observations on occupationally exposed workers
No information.
2.2.4 Observations on general population
No information.
2.2.5 Observations of volunteers
No information.
2.2.6 Reported mishaps
None.
2.3 TOXICITY TO NON-MAMMALIAN SPECIES
The entries in these sections are intended to draw attention to
special risks and to give warning of any needs for special
precautions.
2.3.1 Fish
Harmful
2.3.2 Birds
Harmful
2.3.3 Other species
Harmful to livestock: bees are not affected by acetate.
Dietary Fentin acetate Fentin chloride Fentin hydroxide
studies
Dose Species Effect Dose Species Effect Dose Species Effect
Reproductive 50 ppm Rats Decreased weight 20 ppm Rats Decreased organ
effects (F) of uterus and (M&F) weight, uterus and
after 12 weeks testes after 12
weeks
20 mg/kg Rats 5-20 days produced 20 mg/kg Rats 5-20 days produced 400 ppm Rat Died in 7-34 days
damaged testes and (M&F) (M&F) damaged testes and (M) complete testicular
ovaries ovaries less atrophy
severe than with
acetate
2 ppm Rats 3 generation test
5 ppm (M&F) 5 ppm decreased
testicular size in
1st generation and
at 2 & 5 ppm in 2nd
and 3rd generation.
Immunological 15 ppm Guinea 77 days decreased 5 ppm Rats 12 weeks, decreased
and lymphatic pigs plasma cells in 10 ppm (M&F) leucocytes and
effects (F) spleen and lymph 20 ppm lymphocytes.
nodes Decreased weight of
spleen and thymus.
Dietary Fentin acetate Fentin chloride Fentin hydroxide
studies
Dose Species Effect Dose Species Effect Dose Species Effect
15 ppm Guinea 104 days increased
pigs susceptibility to
(F) tetanus toxoid
decreased
immunologically
active cells
25 ppm Dogs Altered blood
50 ppm (M&F) picture after 16
weeks
5 ppm Dogs 2 years brain water 50 ppm Guinea Increased brain
content increased pigs water content after
(F) 6 weeks
CNS 20 ppm Guinea 12 weeks increased
50 ppm pigs brain water content
50 ppm Rats Increased water
content of spinal
cord after 12
weeks
Part 3. For regulatory authorities
RECOMMENDATIONS ON REGULATION OF COMPOUND
3.1 RECOMMENDED RESTRICTIONS ON AVAILABILITY
(For definition of categories, see introduction)
Formulations of 10% and above, Category 4
Formulations below 10%; Category 5
3.2 TRANSPORTATION AND STORAGE
All formulations
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 Category 4
Protective clothing (see part 4) should be used by 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.
Formulations in Category 5
No special facilities other than those needed for handling of any
chemical, need be required.
3.4 DISPOSAL AND/OR DECONTAMINATION OF CONTAINER
Decontamination of the containers in order to use them for other
purposes should not be permitted. Containers must be either burnt or
crushed and buried below the topsoil. Care must be taken to avoid
subsequent contamination of water sources.
3.5 SELECTION, TRAINING AND MEDICAL SUPERVISION OF WORKERS
Formulations in Category 4
Pre-employment medical examination for workers desirable. Workers
suffering from active hepatic or renal disease should be excluded
from contact. Training of workers to avoid contact essential.
Formulations in Category 5
Warning of workers to minimize contact essential.
3.6 ADDITIONAL REGULATIONS RECOMMENDED IF DISTRIBUTED BY AIRCRAFT
All formulations
Pilot and leaders 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 Category 4
Minimum cautionary statement
Fentin is an organotin fungicide. It is poisonous if swallowed. It
may be absorbed through the skin. Avoid skin contact; wear
protective gloves, clean protective clothing and a respirator when
handling the material. Wash thoroughly with soap and water after
using. Keep the material out of the reach of children and well away
from foodstuffs, animal feed and their containers. If poisoning
occurs, call a physician.
Formulations in Category 5
Minimum cautionary statement
This formulation contains Fentin, an organotin compound. It is
poisonous if swallowed. Keep the material out of the reach of
children and well away from foodstuffs, animal feed and their
containers. If poisoning occurs, call a physician.
3.8 RESIDUES IN FOOD
Maximum residue limits for organotin compounds have been recommended
by the joint FAO/WHO meeting on Pesticide Residues.
Part 4. Prevention of poisoning in man and emergency aid
4.1 PRECAUTIONS IN USE
4.1.1 General
Fentin is an organotin fungicide of moderate toxicity which is only
gradually metabolized. It can be absorbed by mouth, by inhalation of
the 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.
No information.
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 mist and avoid contact with the 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 fentins and associated with their application
should observe the precautions described above in 4.1.3 under
"mixers and applicators".
4.1.5 Other populations likely to be affected
With good agricultural practice subject to 4.2 below other
populations should not be exposed to hazardous amounts of fentin.
4.2 ENTRY OF PERSONS INTO TREATED AREAS
The general population should be kept out of treated areas for at
least one day.
4.3 DECONTAMINATION OF SPILLAGE AND CONTAINERS
Residues in containers should be emptied in a diluted form into a
deep pit taking care to avoid ground waters. Decontamination of
containers in order to use them for other purposes should not be
permitted. Spillage should be removed as far as possible into a deep
dry pit and the remainder washed away with large quantities of
water.
4.4 EMERGENCY AID
4.4.1 Early symptoms of poisoning
These may include lethargy, unsteadiness, moderate diarrhoea and
anorexia, generalized weakness and depression. Limb paralysis is
possible.
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 and wash the affected skin with soap and water if available
and flush the area with large quantities of water. If swallowed,
vomiting should be induced, if the person is conscious.
Part 5. For medical and laboratory personnel
5.1 MEDICAL DIAGNOSIS AND TREATMENT IN CASES OF POISONING
5.1.1 General information
Fentin is an organotin fungicide of moderate toxicity. It is
absorbed from the gastrointestinal tract and the powder may be
inhaled. It is also absorbed by the intact skin. Its mode of action
is on the CNS, although the exact mechanism is not clear. In vitro
work has shown, however, that it is a potent inhibitor of oxidative
phosphorylation and of the ATP activity of brain microsomes. It may
accumulate in the body and has been shown to have a half life of
approximately 50 days in the guinea pig.
5.1.2 Symptoms and signs
These may include depression, lethargy, weakness, unsteadiness,
moderate diarrhoea and anorexia. Limb paralysis has been described
in animals.
5.1.3 Laboratory
There are no specific effects which may be measured to confirm and
monitor the degree of poisoning apart from estimating tin levels in
blood, faeces and urine.
5.1.4 Treatment
Rapid gastric lavage should be performed using 5% sodium bicarbonate
if available. For skin irritation, the skin should be washed with
soap and water. If the compound has entered the eyes, they should be
washed with isotonic saline. Sequestration of the tin with
penicillamine may be attempted but otherwise treatment is
symptomatic.
5.1.5 Prognosis
If the acute toxic effect is survived, the chances of complete
recovery are probably fairly good, however, the acute effects may be
prolonged.
5.1.6 References of previously reported cases
No reported cases.
5.2 SURVEILLANCE TESTS
Monitoring of levels of tin in blood and urine will confirm
exposure.
5.3 LABORATORY METHODS
5.3.1 Detection and assay of compound
Fentins can be estimated absorptiometrically after extraction with
pyro-catecholviolet at 630 mµ. The detection limit is between 0.01
and 0.12 ppm (Ross & White, 1961, Malat 1962).
It may also be converted into the tetrabromo compound separated from
traces of lead and estimated polarographically. The detection limit
of this method is between 0.012 and 0.26 ppm. See Bock & Gorbach
(1958). None of these methods can distinguish between the three
fentin compounds and di- and mono- phenyltin are not detected.
Methods are available to distinguish tri-, di- and monophenyltin,
but difficulties are encountered in the presence of organic
material.
5.3.2 Other tests in cases of poisoning
No specific tests available.
REFERENCES
Bock & Gorbach (1958) Die Bestimmung Kleiner Mengen von
Triphenylzinnacetat,
Pflanzenmaterial Z. analyt. chem., 163, 429-432
Malat (1962) Photometrische Zinnbestimmung mir Brenzcatech-inviolett
in Anwesenheit yon Gelatin; Kolorimetrische Studien III,
ANAL CHEM, 187, 404-409
Ross & White (1961) Application of pyrocatechol-violet as a
colorimetric reagent for tin, ANAL CHEM, 33, 421-427