Monograph: |
Gamma Benzene Hexachloride (lindane)
A white or almost white crystalline powder with a slight mus-
ty odour. Practically insoluble in water: freely soluble in ac-
etone and in chloroform: soluble in dehydrated alcohol:
slightly soluble in ethylene glycol. Protect from light.
Adverse Effects and Treatment
As for Chlorinated Insecticides.
The chlorinated or organochlorine insecticides were widely
used. but because of persistence in man many have been
banned or restricted.
Adverse Effects
Chlorinated or organochlorine insecticides form a very wide
group and the toxicity of individual members varies consider-
ably. In general these insecticides produce symptoms consist-
ent with CNS stimulation. They may be absorbed through the
respiratory and gastro-intestinal tracts and through the skin.
Symptoms of acute poisoning include nausea and vomiting,
paraesthesia, giddiness, tremors, convulsions, coma, and res-
piratory failure. Liver, kidney, and myocardial toxicity have
been reported. Effects on the blood include agranulocytosis
and aplastic anaemia. Symptoms may be complicated by the
effects of the solvent.
Chlorinated insecticides have been reported to enhance mi-
crosomal hepatic enzyme activity. Skin reactions can follow
contact with insecticides.
Polychlorinated biphenyl (PCB) and terphenyl compounds
were formerly used as insecticides in many countries, They
are stored in body fat and are not readily excreted except in
breast milk, although they possibly cross the placenta: be-
cause of this and because of accidental contamination they
remain a cause for concern. The related polybrominated bi-
phenyl compounds (PBB) which have no insecticidal uses
have also been absorbed by the public following accidental
contamination of the food chain.
Some chlorinated insecticides have weak oestrogenic effects;
it has been proposed that exposure may increase the risk of
breast cancer.
Treatment of Adverse Effects
If chlorinated insecticides have been ingested the stomach
should be emptied by lavage. Contaminated clothing should
be removed and the skin washed with soap and water. Treat-
ment is largely symptomatic and supportive with treatment of
CNS stimulation such as hyperactivity and convulsions.
There has been some concern over the application of higher
than normal concentrations of gamma benzene hexachloride to the
skin in the treat-
ment of scabies and pediculosis: children are considered to be
particularly at risk.. Resistance has limited its use in pediculo
sis. so children with that infection tend not to be exposed to it
anyway. However, use has continued in scabies and here treat-
meht should be avoided in young children and in women who
are breast feeding or, are pregnant. Gamma benzene hexachloride
should also be
avoided in patients with a history of epilepsy or who have a
low body-weight.
Seizures have been reported following the topical use of gamma
benzene hexachloride. In reply, one of the manufacturers stated
that up to the
end of 1983 they were aware of 21 cases of convulsive disor-
ders apparently associated with he use of their product; it had
been used by over 40 million people. Of the 21 cases the sei-
zures were definitely or probably caused by the product in 11
but in 9 of them the seizures were associated with ingestion
or excessive use.
Isolated reports of adverse effects associated with gamma benzene
hexachloride include disseminated intravascular coagulation and
subsequent death after oral ingestion3 and aplastic anaemia after
prolonged topical exposure (twice daily application for three
weeks).
Uses and Administration
Gamma benzene hexachloride is a chlorinated insecticide . It has
been used topically in a concentration of 1% for scabies in
selected patients and has also been used in pediculosis but use
for head lice is restricted by resistance.
Gamma benzene hexachloride has been used for the control of
disease vectors including mosquitoes, lice, and fleas but
resistance has developed. It has also been used as an
agricultural and a horticultural insecticide, but its use is
prohibited or restricted in many countries.
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