Captan
| 1. NAME |
| 1.1 Substance |
| 1.2 Group |
| 1.3 Synonyms |
| 1.4 Identification numbers |
| 1.4.1 CAS number |
| 1.4.2 Other numbers |
| 1.5 Main brand names, main trade names |
| 1.6 Main manufacturers, main importers |
| 2. SUMMARY |
| 2.1 Main risks and target organs |
| 2.2 Summary of clinical effects |
| 2.3 Diagnosis |
| 2.4 First-aid measures and management principles |
| 3. PHYSICO-CHEMICAL PROPERTIES |
| 3.1 Origin of the substance |
| 3.2 Chemical structure |
| 3.3 Physical properties |
| 3.3.1 Colour |
| 3.3.2 State/Form |
| 3.3.3 Description |
| 3.4 Hazardous characteristics |
| 4. USES/CIRCUMSTANCES OF POISONING |
| 4.1 Uses |
| 4.1.1 Uses |
| 4.1.2 Description |
| 4.2 High risk circumstance of poisoning |
| 4.3 Occupationally exposed populations |
| 5. ROUTES OF EXPOSURE |
| 5.1 Oral |
| 5.2 Inhalation |
| 5.3 Dermal |
| 5.4 Eye |
| 5.5 Parenteral |
| 5.6 Other |
| 6. KINETICS |
| 6.1 Absorption by route of exposure |
| 6.2 Distribution by route of exposure |
| 6.3 Biological half-life by route of exposure |
| 6.4 Metabolism |
| 6.5 Elimination and excretion |
| 7. TOXICOLOGY |
| 7.1 Mode of Action |
| 7.2 Toxicity |
| 7.2.1 Human data |
| 7.2.1.1 Adults |
| 7.2.1.2 Children |
| 7.2.2 Relevant animal data |
| 7.2.3 Relevant in vitro data |
| 7.2.4 Workplace standards |
| 7.2.5 Acceptable daily intake (ADI) |
| 7.3 Carcinogenicity |
| 7.4 Teratogenicity |
| 7.5 Mutagenicity |
| 7.6 Interactions |
| 8. TOXICOLOGICAL ANALYSES AND BIOMEDICAL INVESTIGATIONS |
| 8.1 Material sampling plan |
| 8.1.1 Sampling and specimen collection |
| 8.1.1.1 Toxicological analyses |
| 8.1.1.2 Biomedical analyses |
| 8.1.1.3 Arterial blood gas analysis |
| 8.1.1.4 Haematological analyses |
| 8.1.1.5 Other (unspecified) analyses |
| 8.1.2 Storage of laboratory samples and specimens |
| 8.1.2.1 Toxicological analyses |
| 8.1.2.2 Biomedical analyses |
| 8.1.2.3 Arterial blood gas analysis |
| 8.1.2.4 Haematological analyses |
| 8.1.2.5 Other (unspecified) analyses |
| 8.1.3 Transport of laboratory samples and specimens |
| 8.1.3.1 Toxicological analyses |
| 8.1.3.2 Biomedical analyses |
| 8.1.3.3 Arterial blood gas analysis |
| 8.1.3.4 Haematological analyses |
| 8.1.3.5 Other (unspecified) analyses |
| 8.2 Toxicological Analyses and Their Interpretation |
| 8.2.1 Tests on toxic ingredient(s) of material |
| 8.2.1.1 Simple Qualitative Test(s) |
| 8.2.1.2 Advanced Qualitative Confirmation Test(s) |
| 8.2.1.3 Simple Quantitative Method(s) |
| 8.2.1.4 Advanced Quantitative Method(s) |
| 8.2.2 Tests for biological specimens |
| 8.2.2.1 Simple Qualitative Test(s) |
| 8.2.2.2 Advanced Qualitative Confirmation Test(s) |
| 8.2.2.3 Simple Quantitative Method(s) |
| 8.2.2.4 Advanced Quantitative Method(s) |
| 8.2.2.5 Other Dedicated Method(s) |
| 8.2.3 Interpretation of toxicological analyses |
| 8.3 Biomedical investigations and their interpretation |
| 8.3.1 Biochemical analysis |
| 8.3.1.1 Blood, plasma or serum |
| 8.3.1.2 Urine |
| 8.3.1.3 Other fluids |
| 8.3.2 Arterial blood gas analyses |
| 8.3.3 Haematological analyses |
| 8.3.4 Interpretation of biomedical investigations |
| 8.4 Other biomedical (diagnostic) investigations and their interpretation |
| 8.5 Overall Interpretation of all toxicological analyses and toxicological investigations |
| 8.6 References |
| 9. CLINICAL EFFECTS |
| 9.1 Acute poisoning |
| 9.1.1 Ingestion |
| 9.1.2 Inhalation |
| 9.1.3 Skin exposure |
| 9.1.4 Eye contact |
| 9.1.5 Parenteral exposure |
| 9.1.6 Other |
| 9.2 Chronic poisoning |
| 9.2.1 Ingestion |
| 9.2.2 Inhalation |
| 9.2.3 Skin exposure |
| 9.2.4 Eye contact |
| 9.2.5 Parenteral exposure |
| 9.2.6 Other |
| 9.3 Course, prognosis, cause of death |
| 9.4 Systematic description of clinical effects |
| 9.4.1 Cardiovascular |
| 9.4.2 Respiratory |
| 9.4.3 Neurological |
| 9.4.3.1 Central nervous system (CNS) |
| 9.4.3.2 Peripheral nervous system |
| 9.4.3.3 Autonomic nervous system |
| 9.4.3.4 Skeletal and smooth muscle |
| 9.4.4 Gastrointestinal |
| 9.4.5 Hepatic |
| 9.4.6 Urinary |
| 9.4.6.1 Renal |
| 9.4.6.2 Others |
| 9.4.7 Endocrine and reproductive systems |
| 9.4.8 Dermatological |
| 9.4.9 Eye, ears, nose, throat: local effects |
| 9.4.10 Haematological |
| 9.4.11 Immunological |
| 9.4.12 Metabolic |
| 9.4.12.1 Acid-base disturbances |
| 9.4.12.2 Fluid and electrolyte disturbances |
| 9.4.12.3 Others |
| 9.4.13 Allergic reactions |
| 9.4.14 Other clinical effects |
| 9.4.15 Special risks |
| 9.5 Others |
| 9.6 Summary |
| 10. MANAGEMENT |
| 10.1 General principles |
| 10.2 Life supportive procedures and symptomatic treatment |
| 10.3 Decontamination |
| 10.4 Enhanced Elimination |
| 10.5 Antidote treatment |
| 10.5.1 Adults |
| 10.5.2 Children |
| 10.6 Management discussion |
| 11. ILLUSTRATIVE CASES |
| 11.1 Case reports from literature |
| 12. ADDITIONAL INFORMATION |
| 12.1 Specific preventive measures |
| 12.2 Other |
| 13. REFERENCES |
| 14. AUTHOR(S), REVIEWER(S), DATE(S) (INCLUDING UPDATES), COMPLETE ADDRESSES |
CAPTAN
International Programme on Chemical Safety
Poisons Information Monograph 098
Chemical
1. NAME
1.1 Substance
Captan
1.2 Group
Chloroalkyl thio fungicide
1.3 Synonyms
Captab (Republic of South Africa);
Captane (France);
N-((trichloromethyl(thio)-4-cyclohexene-1,2-dicarboximide;
N-((trichloromethyl)thio)tetrahydrophthalimide;
N-(trichloromethylmercapto)-delta4-tetrahydrophthalimide;
N-(trichloromethylthio)cyclohex-4-ene-1,2-dicarboximide
(IUPAC);
N-trichloromethylmercapto-4-cyclohexene-1,2-dicarboximide;
N-trichloromethylthio-cis-delta4-cyclohexene-
1,2-dicarboximide;
N-trichloromethylthiocyclohex-4-ene-1,2-dicarboximide;
1.4 Identification numbers
1.4.1 CAS number
133-06-2
1.4.2 Other numbers
EC: 613-044-00-6
ICSC: 0120
RTECS: GW5075000
SR: 406
UN: 2773
1.5 Main brand names, main trade names
Orthocide
Orthocide 406
Vancide 89
A number of formulations are commercially available which
include captan together with other pesticides.
1.6 Main manufacturers, main importers
To be completed by each centre.
2. SUMMARY
2.1 Main risks and target organs
The acute oral toxicity is low. Other than dermatitis
and conjunctivitis, no signs of toxicity directly due to
captan have been reported.
Studies in mice but not in rats have demonstrated a
carcinogenic potential.
2.2 Summary of clinical effects
Captan has caused allergic dermatitis and eye irritation
in man. No other serious adverse effects have been
identified. Evidence from animal experiments indicates that
ingestion of large quantities may produce gastrointestinal
effects such as vomiting and diarrhoea. Solvent vehicles and
other components of the formulated pesticide may complicate
the clinical picture and should be considered.
2.3 Diagnosis
It is based on history of exposure and occurrence of
dermatitis and/or conjunctivitis. Although a sensitive
analytical assay is available for captan, its clinical value
in the management of poisoning seems remote in view of its
low toxicity.
2.4 First-aid measures and management principles
In the event of exposure to captan, contaminated
clothing and (in case of eye contact) contact lenses should
be removed to prevent further absorption. In the case of skin
contact, the affected area should be washed carefully with
soap and water. Wash eyes for 10-15 minutes with clean
running water. First aid personnel should wear rubber or
plastic gloves and avoid contamination.
Ingestion of small amounts of captan does not constitute a
significant risk, and may be managed by dilution with water.
The management of large quantities of ingested captan should
be primarily directed towards decontamination and supportive
care, as there is no specific antidote. The use of Ipecac
Syrup and activated charcoal are indicated in the event of
ingestion.
3. PHYSICO-CHEMICAL PROPERTIES
3.1 Origin of the substance
Captan, a synthetic chloroalkyl thio fungicide, was
introduced in 1949 by the Standard Oil Development Company,
and later by the Chevron Chemical Company. World production
in 1983 was estimated to be 13,000 tonnes.
Captan is formed by reacting tetrahydrophthalimide
(synthesized from maleic anhydride butadiene and ammonia)
with perchloromethylmercaptan (Sittig, 1980).
3.2 Chemical structure
The empirical formula for captan is C9H8CI3NO2S with a
molecular weight of 300.57.
3.3 Physical properties
3.3.1 Colour
White
3.3.2 State/Form
Solid
3.3.3 Description
Pure captan is an odourless, white crystalline
solid. The technical product is an amorphous powder
that is colourless to beige with a pungent odour.
Melting Point: 178°C (pure compound) 158-170°C
(technical grade, 90-95% pure)
Slowly decomposes
Vapour Pressure: < 0.133 mPa at 25°C
Solubility at 25°C Practically insoluble in water
(3.3 mg/L)
Soluble in acetone (21 g/L)
Soluble in chloroform (70 g/L)
Soluble in cyclohexanone (23 g/L)
Soluble in isopropanol (1.7 g/L)
Soluble in xylene (20 g/L)
3.4 Hazardous characteristics
In the dry state, captan is stable at room temperature.
However, in aqueous solution, it is hydrolysed at a rate that
is dependent on the pH. In alkaline solution, the breakdown
is rapid.
Captan is not flammable but on heating may produce toxic
fumes such as sulphur dioxide, hydrochloric acid, and
phosgene. These may be harmful by inhalation and skin
contact. Extinguish small fires with carbon dioxide, dry
powder or alcohol-resistant foam. Water spray can be used for
larger fires and for the cooling of unaffected stock, but
avoid the accumulation of polluted run-off from the site.
Fire fighters should wear full protective clothing including
self-contained breathing apparatus.
Although the pure substance is practically insoluble in
water, the formulated product may pose an environmental risk
if released into an aquatic environment. Captan is highly
toxic to fish: a LC50 (96h) range of 0.03 - 0.07 mg/L has
been reported for various species. Captan is moderately toxic
to freshwater invertebrates, such as daphnia (48h LC50
between 1 and 8 mg/L). Captan is not persistent, and its use
is not considered to be a threat to terrestrial wildlife. It
is not toxic to bees.
The environmental impact of the pesticide is likely to be
limited by its high rate of hydrolysis and the lack of any
tendency to bioaccumulate. The half-life in lake water is 7h
at 12°C and 1 h at 23°C. However, because of its demonstrated
high toxicity, exposure of aquatic organisms to captan
through drift and/or run-off is a cause for concern (WHO,
1990).
Alkaline treatment of captan leads to the formation of
non-toxic degradation products and is considered to be an
environmentally acceptable disposal method (Dillon, 1981).
Small spillages and residues could be treated with alkali
before burial in an approved landfill area. During
neutralization, hydrogen sulphide may be formed if
insufficient alkali is used. Personnel involved in captan
disposal should be provided with protective equipment which
should minimize skin, ocular and respiratory exposure.
4. USES/CIRCUMSTANCES OF POISONING
4.1 Uses
4.1.1 Uses
4.1.2 Description
Captan is fungicide used to control diseases of
many fruit and ornamental and vegetable crops. It is
also used as a spray, root dip or seed treatment, to
protect young plants against rot and damping off
(Worthing, 1987). Captan is also used as a fungicide
in wallpaper pastes and in hormone rooting
powders.
4.2 High risk circumstance of poisoning
Accidents among adult farm workers and secondary
exposure of their children.
Exposure of the general population may occur through the
consumption of foodstuffs treated incorrectly with captan or
harvested prematurely before residues have declined to
acceptable levels or from contact with treated areas.
Accidental ingestion of wallpaper pastes and hormone rooting
powders by children.
4.3 Occupationally exposed populations
Factory workers involved in synthesizing captan.
Workers involved in formulating and dispensing pesticides.
Agricultural spray workers. Crop harvesters during disease
vector control periods.
5. ROUTES OF EXPOSURE
5.1 Oral
Although no literature accounts were available at the
time of preparation of this monograph, the ingestion of
captan either accidentally or intentionally is
possible.
5.2 Inhalation
Inhalation of captan as spray mists or powders is
possible, particularly in an occupational context. A TLV has
been established by ACGIH (see Section 7.2.4).
5.3 Dermal
The extent of dermal absorption in humans is not known,
however it is considered to be very limited (WHO,
1990).
5.4 Eye
No data available.
5.5 Parenteral
No data available.
5.6 Other
No data available.
6. KINETICS
6.1 Absorption by route of exposure
Following oral administration of [35S]captan to rats at
a dose of 143 or 390 mg/kg, at least 60% was excreted in the
urine (Seidler et al, 1971).
6.2 Distribution by route of exposure
Both captan and its metabolites are rapidly eliminated
(> 90% within 24h) (WHO, 1990).
When captan tagged with 14C in the trichloromethyl group was
administered to rats orally, activity was recovered as
follows:
51.8% urine
22.8% expired air
15.9% faeces
0.6% tissues (De-Baun et al., 1974)
6.3 Biological half-life by route of exposure
No data available.
6.4 Metabolism
Urinary metabolites from the rats fed 14C-captan
included thiozolidine-2-thione-4-carboxylic acid, a salt of
dithiobis (methane sulphonic acid), and the disulphide
monoxide derivative of dithiobis (methane sulphonic acid).
The latter two derivatives were not detected in the urine of
rats that received captan intra-peritoneally. This, and other
evidence, indicates that degradation in the gastrointestinal
tract plays a major role in the metabolism of captan (De-Baun
et al 1974).
A greater proportion of a high dose of captan reaches the
small intestine of the mouse compared with the rat (WHO,
1990).
6.5 Elimination and excretion
Following an oral dose of [35S]captan to rats at a rate
of 143 or 390 mg/kg, at least 60% was excreted in the urine
(Seidler et al, 1971). Within the first 24 hours, more than
90% was excreted in the urine and faeces, and almost all the
rest was excreted during the next two days. Only 0.01-0.05%
of the radioactivity was deposited in the organs in the form
of metabolites or of moieties incorporated into normal body
constituents.
After oral administration of 14C-captan to rats, 52% of the
dose appeared in the urine; 23% in expired air; and 16% in
the faeces (De-Baun et al, 1974).
7. TOXICOLOGY
7.1 Mode of Action
No data available.
7.2 Toxicity
7.2.1 Human data
7.2.1.1 Adults
The acute oral toxicity of captan
(technical grade) for humans is considered to
be low (WHO, 1990).
7.2.1.2 Children
No data available.
7.2.2 Relevant animal data
Most investigators have found that captan has a
low oral toxicity in laboratory animals. LD50 (oral)
in the rat of 12,600 mg/kg and > 17,000 mg/kg have
been found. The reported effect of very severe
protein deficiency increases the susceptibility of
rats far more to captan than to any other pesticide
investigated. The mechanism of this action is unknown
(Hayes & Laws, 1991).
In the most thorough study of repeated doses of captan
given by stomach tube to rats, the 100-day LD50 was
916 mg/kg/day (Hayes & Laws, 1991).
Mouse LD50 7000 mg/kg (oral)
Mouse LD50 462 mg/kg (ip)
Mouse LC50 5000 mg/m3/2h (inhalation)(RTECS, 1987)
Sheep and, to a lesser degree, cattle, are especially
susceptible to captan. A single oral dose of 250
mg/kg may be fatal in sheep (Hayes and Laws,
1991).
7.2.3 Relevant in vitro data
Captan, which is an alkylating agent, has
demonstrated genotoxic properties in in-vitro systems
(WHO, 1990).
7.2.4 Workplace standards
The threshold limit value (TWA) recommended by
the US ACGIH for captan is 5 mg/m3 in the air (WHO,
1990).
7.2.5 Acceptable daily intake (ADI)
The Joint FAO/WHO Meeting on Pesticide Residues
has established an ADI of 0 - 0.1 mg/kg bodyweight.
Using the same data base, the EEC calculated the same
ADI value at 0.013 mg/kg/day. On the basis of
reproduction studies, a reference dose of 0.013
mg/kg/day for non-neoplastic effects has been
established by the US Environmental Protection Agency
(WHO, 1990).
7.3 Carcinogenicity
Long-term administration of high dietary levels of
captan to mice resulted in the induction of benign and
malignant tumours of the small intestine. The situation
regarding carcinogenicity in the rat is less clear: in one
study, a slight increase in the incidence of kidney tumours
was found. However, the carcinogenic potential of captan in
rodents relative to other experimental carcinogens is
low.
7.4 Teratogenicity
The results of animal studies on the teratogenicity of
captan are contradictory. To date, there is no evidence of
teratogenicity in mice or primates (see Section 9.4.15). In
one experiment in hamsters, there was no teratogenic
response; in another (the only difference in experimental
regimen being the day of treatment), captan induced central
nervous system and rib defects in 23% of foetuses. Similar
results were observed in the rabbit: one experiment found no
congenital abnormalities, while another with an identical
regimen demonstrated limb and head defects and cleft palate
with a frequency of nearly 50%. In the dog, no defects were
produced in one study, but tail, closure defects, and
hydrocephalus were induced in another.
It is difficult to assess the risk from this evidence and
definitive experiments are required adequately to determine
the full spectrum of developmental toxicity with this
compound (Schardein, 1985).
7.5 Mutagenicity
Captan appears to be mutagenic in susceptible cell
cultures, but expert opinion holds that it is not mutagenic
in intact higher animals except perhaps at the doses
encountered in suicide attempts (Hayes & Laws, 1991).
Captan is an alkylating agent and is genotoxic in vitro but
not in vivo. Although captan may be able to induce genotoxic
events in somatic cells, present evidence indicates that the
potential for causing inheritable effects is extremely low
(WHO, 1990).
7.6 Interactions
No data available.
8. TOXICOLOGICAL ANALYSES AND BIOMEDICAL INVESTIGATIONS
8.1 Material sampling plan
8.1.1 Sampling and specimen collection
8.1.1.1 Toxicological analyses
8.1.1.2 Biomedical analyses
8.1.1.3 Arterial blood gas analysis
8.1.1.4 Haematological analyses
8.1.1.5 Other (unspecified) analyses
8.1.2 Storage of laboratory samples and specimens
8.1.2.1 Toxicological analyses
8.1.2.2 Biomedical analyses
8.1.2.3 Arterial blood gas analysis
8.1.2.4 Haematological analyses
8.1.2.5 Other (unspecified) analyses
8.1.3 Transport of laboratory samples and specimens
8.1.3.1 Toxicological analyses
8.1.3.2 Biomedical analyses
8.1.3.3 Arterial blood gas analysis
8.1.3.4 Haematological analyses
8.1.3.5 Other (unspecified) analyses
8.2 Toxicological Analyses and Their Interpretation
8.2.1 Tests on toxic ingredient(s) of material
8.2.1.1 Simple Qualitative Test(s)
8.2.1.2 Advanced Qualitative Confirmation Test(s)
8.2.1.3 Simple Quantitative Method(s)
8.2.1.4 Advanced Quantitative Method(s)
8.2.2 Tests for biological specimens
8.2.2.1 Simple Qualitative Test(s)
8.2.2.2 Advanced Qualitative Confirmation Test(s)
8.2.2.3 Simple Quantitative Method(s)
8.2.2.4 Advanced Quantitative Method(s)
8.2.2.5 Other Dedicated Method(s)
8.2.3 Interpretation of toxicological analyses
8.3 Biomedical investigations and their interpretation
8.3.1 Biochemical analysis
8.3.1.1 Blood, plasma or serum
8.3.1.2 Urine
8.3.1.3 Other fluids
8.3.2 Arterial blood gas analyses
8.3.3 Haematological analyses
8.3.4 Interpretation of biomedical investigations
8.4 Other biomedical (diagnostic) investigations and
their interpretation
8.5 Overall Interpretation of all toxicological analyses
and toxicological investigations
Sample collection
Not relevant.
Biomedical analysis
Not relevant.
Toxicological analysis
No specific laboratory tests are necessary unless clinically
indicated. Although a sensitive assay is available for
captan, its clinical value in the management of exposure
seems limited in view of the low toxicity of captan.
Other investigations
No data available.
8.6 References
9. CLINICAL EFFECTS
9.1 Acute poisoning
9.1.1 Ingestion
The acute oral toxicity of captan is low and
acute overdosage is not expected to result in severe
toxicity. Evidence from animal experiments using
structurally related compounds indicates that
gastrointestinal effects (vomiting and diarrhoea) may
occur (Hayes & Laws,1991)
9.1.2 Inhalation
No data available.
9.1.3 Skin exposure
Allergic dermatitis has been reported (Hayes
and Laws, 1991).
9.1.4 Eye contact
Conjuctivitis has been reported (Hayes and
Laws, 1991)
9.1.5 Parenteral exposure
The toxicity of captan in the mouse is greater
after peritoneal injection than after oral
administration. Toxicity may therefore be greater in
the unlikely event of intravenous
administration.
9.1.6 Other
No data available.
9.2 Chronic poisoning
9.2.1 Ingestion
No human data are available.
In dogs fed captan 300 mg/kg/day for 48 weeks
following 18 weeks at lower doses, there was a slight
increase in liver and kidney weight (Hayes and Laws,
1991).
In a 100-day LD50 study in the rat, signs of toxicity
included weight loss, decreased food intake, increased
water intake, diarrhoea, hypothermia and prostration.
These were most marked during the first three weeks of
administration (Boyd and Carsky, 1971).
No data available in humans.
9.2.2 Inhalation
No data available.
9.2.3 Skin exposure
Allergic dermatitis has been reported (Hayes &
Laws, 1991).
9.2.4 Eye contact
No data available.
9.2.5 Parenteral exposure
No data available.
9.2.6 Other
No data available.
9.3 Course, prognosis, cause of death
No human fatalities have been reported. The toxicity is
low.
9.4 Systematic description of clinical effects
9.4.1 Cardiovascular
No data available.
9.4.2 Respiratory
No data available.
9.4.3 Neurological
9.4.3.1 Central nervous system (CNS)
No data available.
9.4.3.2 Peripheral nervous system
No data available.
9.4.3.3 Autonomic nervous system
No data available.
9.4.3.4 Skeletal and smooth muscle
No data available.
9.4.4 Gastrointestinal
The acute oral toxicity of captan is low and
acute overdosage is not expected to result in severe
toxicity. Evidence from animal experiments using
structurally related compounds indicates that
gastrointestinal effects (vomiting and diarrhoea) may
occur (Hayes & Laws,1991).
9.4.5 Hepatic
Chronic feeding studies using high oral doses
of captan in dogs showed a slight increase in liver
weight (see section 9.2.1).
Animal studies showed that large doses of captan (1000
mg/kg/day for 7 days) induced alterations of serum
concentrations of liver enzymes (Hayes & Laws,
1991).
9.4.6 Urinary
9.4.6.1 Renal
Chronic feeding studies using high
oral doses of captan in dogs showed a slight
increase in kidney weight (see section
9.2.1).
9.4.6.2 Others
No data available.
9.4.7 Endocrine and reproductive systems
A study on pseudo-pregnant and pregnant rats
showed a reduction in uterine weight, particularly
affecting the endometrium, occurring in a
dose-dependent fashion up to 10,000 ppm (Hayes and
Laws, 1991).
9.4.8 Dermatological
Allergic dermatitis has been reported in humans
(Hayes and Laws, 1991).
Sensitivity to captan was demonstrated among
volunteers following application to the skin of the
back (Jordan and King, 1977).
9.4.9 Eye, ears, nose, throat: local effects
Conjunctivitis has been reported in humans
(WHO, 1990).
9.4.10 Haematological
No data available.
9.4.11 Immunological
Allergic dermatitis has been reported in
humans (Hayes and Laws, 1991).
Immunological function was not significantly altered
in weanling rats fed 2,000 mg/kgdid (Hayes and Laws,
1991).
9.4.12 Metabolic
9.4.12.1 Acid-base disturbances
No data available.
9.4.12.2 Fluid and electrolyte disturbances
No data available.
9.4.12.3 Others
No data available.
9.4.13 Allergic reactions
Allergic dermatitis has been reported in
humans (Hayes and Laws, 1991).
9.4.14 Other clinical effects
No data available.
9.4.15 Special risks
Captan was administered to pregnant rhesus
monkeys at dosages of 10, 25 and 75 mg/kg/day and to
stump-tailed macaques at dosages of 10 and 75
mg/kg/day during days 21-24 or 34 of gestation. The
highest dose was given from day 21 through 34.
Thalidomide at a dosage of 5 or 10 mg/kg/day was
administered as a positive control. Captan produced no
abortions, no anomalies in the young,and no injury for
the mothers. Typical deformities and numerous
abortions were produced by thalidomide in both kinds
of non-human primate (Vondruska et al, 1971) (see
section 7.4).
9.5 Others
No data available.
9.6 Summary
10. MANAGEMENT
10.1 General principles
Ingestions of small amounts of captan (less than 10
mg/kg body weight) do not constitute a significant risk, and
may be managed by dilution with water.
The management of large quantities of ingested captan (more
than 10 mg/kg bodyweight) should be primarily directed
towards decontamination and supportive care, as there is no
specific antidote. The use of Ipecac Syrup and activated
charcoal are indicated in the event of ingestion.
10.2 Life supportive procedures and symptomatic treatment
Following large ingestions of captan, there are no
specific procedures recommended other than the basic
techniques for maintaining airways, breathing and
circulation.
10.3 Decontamination
Wash contaminated skin with soap and water.
Flush contaminated eyes (remove contact lenses if worn) with
copious amounts of fresh water for 10 to 15 minutes.
Ingestions of small amounts (less than 10 mg/kg bodyweight)
occurring less than one hour before treatment are probably
best managed by simple dilution with water.Ingestions of
large amounts (more than 10 mg/kg bodyweight) occurring less
than one hour before treatment, are probably best treated by:
syrup of ipecac and activated charcoal.
Ingestions occurring more than one hour before treatment are
probably best treated only by: activated charcoal (30 to
50 g)
10.4 Enhanced Elimination
No specific elimination procedures have been established.
10.5 Antidote treatment
10.5.1 Adults
There is no specific antidote for
captan.
10.5.2 Children
There is no specific antidote for
captan.
10.6 Management discussion
There is an absence of clinical data on ingestion of
captan in man; research into the allergic response mechanism
and definitive experiments are required adequately to
determine the full spectrum of foetal toxicity.
11. ILLUSTRATIVE CASES
11.1 Case reports from literature
Case 1: adult male, occupational exposure. Skin
reaction. A 73-year-old retired fruit grower exhibited
persistent erythema, itching, and desquamation of the face
and backs of hands. The condition was exacerbated when he
was close to spraying operations using captan. Skin testing
revealed reaction to captan (Dooms-Goossens et al, 1986).
Case 2: adult male, occupational exposure. Skin reaction. An
18-year-old gardener was sufficiently sensitive to captan
that he reacted to treated plants as well as to the
formulation. Inhalation and skin test established that captan
was the factor in the formulation to which the patient
reacted. Recovery was prompt after exposure was stopped
(Hayes & Laws, 1991).
12. ADDITIONAL INFORMATION
12.1 Specific preventive measures
It is essential that persons intending to use captan
are provided with adequate health precautions and other
safety instructions prior to usage. This information should
be provided by the manufacturer in the form of either an
information leaflet or on a labal attached to the captan
container.
Protective clothing is important. Captan may cause skin
irritation and sensitization. The risk of this is greatest in
hot weather when the user is sweating. Protective measures
may include wearing a long-sleeved shirt, long trousers or
overalls, and a hat. Respiratory protection should be
considered. The label should give these details.
Clothing worn during spraying should be washed daily after
use. Contaminated clothing should be washed separately from
the general wash to avoid cross-contamination. When working
with liquids, there is often a danger of a splash in the
eyes. Simple goggles or a face shield will protect against
this. Eye protection is most important if wearing contact
lenses: captan may seep behind the lenses and, in the time
taken to remove them from the eyes prior to irrigation,
serious damage can occur.
Greater precautions are necessary when mixing the
concentrated material than when spraying. Measurements should
be accurate and spillages should be cleaned up promptly. Mix
the chemical carefully using a stick or paddle. Minimise skin
exposure by wearing gloves. If any concentrate is spilled on
the skin, it should be washed off as soon as possible.
The hazards of spraying increase dramatically on windy days
as there is an increased risk of inhaling spray drift or
contaminating the skin. Also, the risk of drift onto other
properties or crops is increased.
Always wash hands before eating, drinking or smoking. After
spraying, shower and change clothing.
Captan should be stored in a locked shed, safely out of reach
of children and animals. Captan should also be kept away from
work areas and separate from other stored materials such as
animal foods. Always leave captan in its original containers,
or if it must be transferred to another container ensure that
this is one not normally used for food or drink. This
container should be well-labelled and of a variety that is
not likely to leak.
Empty containers must be disposed of carefully, so as to
ensure that rivers, streams, and other water sources are not
polluted, and that unsuspecting people or animals are not
exposed to residues or concentrate. Crushing or burning,
followed by burial, is generally the best method. Workers
involved in harvesting crops must adhere carefully to
re-entry standards which have been set in order to prevent
toxicity from captan.
12.2 Other
First-aid sheet:
Poisoning from captan may occur after it is absorbed
following:
Ingestion
Contact with the skin
Contact with the eyes
Inhalation
Signs and Symptoms
Ingestion may cause vomiting and diarrhoea.
Skin contact and inhalation may result in local
irritation and also sensitisation.
Eye contact may produce conjunctivitis.
Decontamination
It is important that captan is removed as quickly as
possible. Contaminated clothing and contact lenses
should be removed. Avoid contact of captan with skin
and eyes; first aid personnel should wear rubber or
plastic gloves and avoid contamination.
Treatment - General
Never give fluids or induce vomiting if the patients
is unconscious or fitting.
The patient must be watched constantly.
It is important to keep the airways open and to
prevent inhaling the vomit if nausea and vomiting is a
problem.
Give artificial respiration if the patient is not
breathing.
Treatment - Ingestion
Give one to two cups of cold water. Vomiting may be
induced if advised by medical personnel. Obtain
medical attention.
Treatment - Skin
Remove all contaminated clothing immediately.
Wash affected area carefully with soap and rinse with
copious amounts of water. Obtain medical
attention.
Treatment - Eyes
Make sure any contact lenses are removed.
Flush with water for 10-15 minutes. Obtain medical
attention.
Treatment - Inhalation
Remove the patient from the area of exposure. Be
careful to avoid any contact with captan. Protect
skin and eyes. Give oxygen if available. Obtain
medical attention.
13. REFERENCES
Boyd E and Carsky E (1971) The 100-day LD50 Index of Captan.
Acta Pharmacol. Toxicol. 29: 226-240.
De-Baun JR, Miaullis JB, Knarr J., Mihailovski A and Menn JJ
(1974) The fate of
N-trichloro14Cmethylthio-4-cyclohexane-1,2-dicarboximide (14C
captan) in the rat. Xenobiotica, 4: 101-110.
Dillon AP, ed. (1981) Pesticide disposal and detoxification.
Processes and techniques. Noyes Data Corporation, New Jersey,
USA, 588 pp.
Dooms-Goossens AE, Debusschere KM, Gevers DM, Dupr_ KM, Degreef
HJ, Loncke JP and Snauwaert JE (1986) Contact dermatitis caused
by airborne agents. J. Am. Acad. Dermatol., 15: 1-9.
Hayes WJ Jr and Laus ER Jr (1991) Pesticides studied in man.
Volume 3. Williams and Wilkinson, Baltimore, 1576 pp.
Jordan WP and King SE (1977) Delayed hypersensitivity in females.
The development of allergic contact dermatitis in females during
the comparison of two predictive patch tests.
Contact Dermatitis, 3: 19-26.
RTECS (1987) Registry of Toxic Effects of Chemical Substances,
1985-1986 Edition. US Department of Health and Human Services,
Public Health Service, Centers for Disease Control, National
Institute for Occupational Safety and Health, 5147 pp.
Schardein JL, ed. (1985) Chemically induced birth defects.
Marcel Dekker Incorporated, New York, USA, 879 pp.
Seidler H, Haertig M, Schnaak W and Engst R (1971) Studies on the
metabolism of some insecticides and fungicides in the rat. 3.
Excretion, distribution and metabolism of 35S captan. Nahrung,
15: 177-185 (in German).
Sittig M, ed. (1980) Pesticide Manufacturing and Toxic Control
Encyclopaedia. Noyes Data Corporation, Park Ridge, New Jersey,
USA, 810 pp.
Vondruska JF, Fancher OE and Calandra JC (1971) An investigation
into the teratogenic potential of captan, folpet and Difolatan in
non-human primates. Toxicol. Appl. Pharmacol., 18: 619-624.
WHO (1990) IPCS Health and Safety Guide No. 50. Captan Health and
Safety Guide. World Health Organization, Geneva.
Worthing CR, ed. (1987) The Pesticide Manual. British Crop
Protection Council, Worcestershire, 1077 pp.
14. AUTHOR(S), REVIEWER(S), DATE(S) (INCLUDING UPDATES),
COMPLETE ADDRESSES
Authors: Dr Wayne A. Temple
National Poisons and Hazardous Chemicals Information
Centre
Dr Nerida A. Smith
School of Pharmacy
University of Otago Medical School
P.O. Box 913
Dunedin
New Zealand
Tel: 64-3-4797244
Fax: 64-3-4770509
Date: 29 October 1992
Reviewer: Ms J. Tempowski
London Poisons Unit
New Cross Hospital
Avonley Road
London SE14 5ER
United Kingdom
Tel: 44-71-9555095
Fax: 44-71-6392101
Date: February 1992
Peer Review: Newcastle-upon-Tyne, United Kingdom, February 1992
Review: IPCS, May 1994