Arsenic provides a classic case of the virtually permanent pois oning of the s oil. Although ars enic
as a spray on growing tobacco has been largely replaced by the synthetic organic insecticides
s ince the mid-40s, the arsenic content of cigarettes made from American-grown tobacco
increased more than 300 per cent between the years 1932 and 1952. Later s tudies have
revealed increases of as much as 600 per cent. Dr. Henry S. Satterlee, an authority on arsenic
toxicology, says that although organic insecticides have been largely substituted for arsenic, the
tobacco plants continue to pick up the old pois on, for the s oils of tobacco plantations are now
thoroughly impregnate d with res idues of a heavy and relatively insoluble poison, arsenate of
lead. This will continue to release arsenic in soluble form. The soil of a large proporti on of the
land planted to tobacco has been s ubjected to ‘cumulative and well-nigh permanent pois oning’,
according to Dr. Satterlee. Tobacco grown in the eas tern Medite rranea n countries where
arsenical insecticides are not us ed has s hown no s uch increas e in ars enic content.
We are the refore conf ronted with a s econd proble m. We mus t not only be conce rned with
what is happening to the s oil; we mus t wonde r to what extent ins ecticides are abs orbed from
contami nated s oils and introduced into plant tis s ues. Much depends on the type of s oil, the
crop, and the nature and concentrati on of the ins ecticide. Soil high in organic matter releases
s maller quantities of pois ons than others. Carrots abs orb more ins ecticide than any other crop
s tudied; if the chemical us ed happens to be lindane, carrots actually accumulate higher
concentrations than a re pres ent in the s oil. In the future it may bec ome necessary to analyze
s oils for ins ecticides before planting certain f ood c rops. Otherwis e even uns prayed crops may
take up enough ins ecticide merely from the s oil to render the m unfit for marke t. This very s ort
of conta mination has created endles s problems for at leas t one leading manufacturer of baby
foods who has been unwilling to buy any fruits or vegetables on which toxic insecticides have
been us ed. The chemical that caus ed him the mos t trouble was benzene hexachloride (BHC),
which is taken up by the roots and tube rs of plants , advertis ing its pres ence by a mus ty tas te
and odor. Sweet potatoes grown on California fields where BHC had been us ed two years
earlier contained res idues and had to be rejected. In one yea r, in which the firm had contracted
in South Carolina for its total require ments of s weet potatoes , s o large a proportion of the
acreage was found to be conta minated that the company was forced to buy in the ope n ma rket
at a considerable financial loss. Over the years a variety of fruits and vegetables, grown in
various s tates , have had to be rejected. The mos t s tubborn proble ms were concerned with
peanuts. In the s outhern s tates peanuts are us ually grown in rotation with cotton, on which
BHC is extensively used. Peanuts grown later in this s oil pick up considerable amounts of the
insecticide. Actually, only a trace is enough to incorporate the telltale mus ty odor and tas te.
The chemical penetrates the nuts and cannot be re moved. P roces s ing, far from re moving the
mus tines s , s ometimes accentuates it. The only cours e open to a manufacture r determined to
exclude BHC residues is to reject all produce treated with the chemical or grown on soils
contami nated with it. Someti mes the menace is to the crop itself—a menace that remains as
long as the insecticide contamination is in the soil. Some insecticides affect sensitive plants such
as beans, wheat, barley, or rye, retarding root developme nt or depres s ing growth of s eedlings.
The experience of the hop growers in Was hington and Idaho is an example. During the s pring of
1955 many of thes e growers unde rtook a large-s cale program to control the s trawberry root
weevil, whos e larvae had become abundant on the roots of the hops. On the advice of
agricultural experts and insecticide manufacturers, they chos e heptachlor as the control agent.
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