s ymptoms. And as we have s een, pairs of the organic phos phates themselves may interact in
s uch a way as to increas e their toxicity a hundredf old. Or the organic phos phates may inte ract
with various drugs, or with synthetic materials, food additives—who can s ay what els e of the
infinite number of manma de s ubs tances that now pervade our world?
The effect of a chemical of s uppos edly innocuous nature can be dras tically changed by the
action of another; one of the best examples is a close relative of DDT called methoxychlor.
(Actually, methoxychlor may not be as free from dangerous qualities as it is generally said to be,
for recent work on experimental animals shows a direct action on the ute rus and a blocking
effect on some of the powerf ul pituitary hormones—reminding us again that these are
chemicals with enormous biologic effect. Other work s hows that me thox ychlor has a potential
ability to damage the kidneys.) Because it is not stored to any great extent when given alone,
we are tol d that methoxychlor is a safe chemical. But this is not neces s arily true. If the liver has
been damaged by anothe r agent, methoxychl or is s tored in the body at 100 times i ts normal
rate, and will then imitate the effects of DDT with long-las ting effects on the nervous system.
Yet the liver damage that brings this about might be s o s light as to pass unnoticed. It might
have been the res ult of any of a numbe r of commonplace situations—us ing anothe r ins ecticide,
using a cleaning fluid containing carbon tetrachloride, or taking one of the s o-called
tranquilizing drugs , a numbe r (but not all) of which are chlorinate d hy drocarbons and pos s ess
powe r to da mage the liver.
Damage to the ne rvous s ys tem is not confined to acute pois oning; there may als o be delayed
effects from expos ure. Long-las ting damage to brain or nerves has been reporte d for
methoxychlor and others. Dieldrin, besides its immediate cons eque nces , can have long delayed
effects ranging from ‘loss of memory, insomnia, and nightmares to mania’. Lindane, according
to medical findings , is s tored in s ignificant amounts in the brain and func tioning liver tis s ue and
ma y induce ‘prof ound and long las ting effects on the central nervous s ys tem’. Yet this chemical,
a form of benzene hexachloride, is much us ed in vaporizers , devices that pour a s tream of
volatilized insecticide vapor into homes, offices, res taurants. The organic phos phates , us ually
considered only in relation to their more violent manifestations in acute poisoning, also have
the powe r to produce las ting physical damage to nerve tissues and, according to recent
findings , to induce mental disorders. Various cases of delayed paralysis have followed use of
one or anothe r of thes e ins ecticides. A bizarre happening in the United States during the
prohibition era about 1930 was an omen of things to come. It was caus ed not by an insecticide
but by a s ubs tance belonging chemically to the same group as the organic phos phate
ins ecticides. During that period s ome medicinal s ubs tances were being pres s ed into s ervice as
subs titutes for liquor, being exempt f rom the prohibition law. One of these was Jamaica ginger.
But the United States Pharmacopeia product was expensive, and bootleggers conceived the
idea of making a substitute Jamaica ginger. They succeeded so well that their s purious product
res ponde d to the appropriate chemical tes ts and deceived the governme nt chemis ts. To give
their false ginger the necess ary tang they had introduced a chemical known as triorthocres yl
phos phate. This chemical, like parathion and its relatives , des troys the protective enzyme
cholines teras e. As a cons equence of drinking the bootleggers ’ product s ome 15,000 people
developed a permanently crippling type of paralysis of the leg muscles, a condition now called
‘ginger paralysis’. The paralysis was accompanied by des truction of the nerve s heaths and by
degeneration of the cells of the anterior horns of the s pinal cord.
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