Evening star. [volume] (Washington, D.C.) 1854-1972, 1962-11-28
SILENT SPRING
Continued From Page D-20

nature accomplishes far-reach-
ing aims. Explosive increases
in some kiAds Of soil organisms
have occurred when others have
been reduced by insecticides,
disturbing the relation Of
predator to prey. Such changes
could easily alter the metabolic
activity Of the soil and affect
its productivity. They could also
mean that potentially harmful
organisms, formerly held in
check, could escape from their
natural controls and rise to
pest status.
One of the most important
things to remember about in
secticides in soil is their long
persistence, measured not In
months but In years.
Arsenic provides q classic
case Of the virtually perma-
nent poisoning of the soil. Al
though arsenic as q spray on
growing tobacco has been
largely replaced by the syn
thetic organic insecticides since
the mid-40s, the arsenic con-
tent Of cigarettes made from
American-grown tobacco in
creased more than 800 per cent
between the years 1882 and
1852.
Later studies have revealed
increases Of as much as 500
per cent.
DR.. Henry 8. Satterlee, an
authority on arsenic toxicology,
says that although organic in
secticides have been largely
substituted for arsenic. the
tobacco plants continue to pick
up the old poison. for the soils
Of tobacco plantations are now
thoroughly impregnated with
residues Of q heavy and rela-
lively insoluble poison. arsenate
Of lead. This win continue to
release arsenic in soluble form.
The soil Of q large proper
ton of the land planted to
tobacco has been subjected to
cumulative and well-nigh per-
manent poisoning" according
to DR.. Satterlee.
Tobacco grown In the eastern
Mediterranean countries where
arsenical insecticides are not
used has shown no such in
crease in arsenic content.
We are therefore confronted
with q second problem. We
must not only be concerned
with what Is happening to the
soil; we must wonder to what
extent insecticides are absorbed
from contaminated soils and
introduced into plant tissues.
Some Produce Rejected
This very sort of contamina-
ton created endless problems
for at least one leading manu-
facturer of baby foods who was
unwilling to buy any fruits or
vegetables on which toxic in
secticides have been used. The
chemical that caused him the
most trouble was benzene hex
achloride CBHC). which is
taken up by the roots and
tubers Of plants, advertising
its presence by a musty taste
and odor.
Sweet potatoes grown on
California fields where BIC
had been used two years earlier
contained residues and had to
be rejected. In one year, in
which the firm had contracted
in South Carolina for its total
requirements Of sweep potatoes.
so large q proportion Of the
acreage was found to be con-
taminated that the company
was forced to buy in the open
market at q considerable H.
nancial loss.
Over the years a variety Of
fruits and vegetables, grown
In various States. have had to
be rejected. The most stub
born problems were. concerned
with peanuts. In the southern
States peanuts are usually
grown In rotation with cotton.
on which BIC Is extensively
used. Peanuts grown later in
this soil pick UP considerable
amounts of the irisecticide.
Actually, only q trace is enough
to incorporate the telltale
musty odor and taste. The
chemical penetrates the nuts
and cannot be removed. Proc
essing, far from removing the
mustiness, sometimes accentu-
ates 1t. The only course open
to q manufacturer determined
to exclude BIC residues is to
reject all produce treated with
the chemical or grown on soils
contaminated with 1t.
Sometimes the menace is to
the crop itself-a menace that
remains as long as the In.
secticide contamination Is In
the soil. Some insecticides af-
feet sensitive plants such as
beans, wheat, barley. or rye,
retarding root development or
depressing growth Of seedlings.
AS applications Of pesticides
continue and the virtually In
destructible residues continue
to build UP in the soil. 1t Is
almost certain that we are
heading for trouble. This was
the consensus of q group Of
specialists who met at SYRIA
cuse University in 1860 to dis
cuss the geology Of the soil.
These men summed Up the
hazards of using such potent
and little understood tools as
chemicals and radiation: "a
few false moves on the part
Of man may result in destruc-
ton of soil productivity and
the arthropods may well take
over"
CopyriEht. 1862, by Rachel Carson.
Published by Houghton Mifflin Co.
Tomorrow: Eorth's Green MontIe.