The manufacture of pesticides is a remarkably successful business. As
recently as 1940, the pesticide trade hardly existed at all, yet by
1990 some 2.5 million tons (5 billion pounds) of pesticides were used
worldwide. This is one pound per year for every human being on earth.
Pesticide manufacturers reaped $3 billion in 1970 but by 1990 their
sales had grown to $19 billion.
Per-capita pesticide use in the U.S. is over three times the global
average. Each year about 820 million pounds of pesticides are used in
the U.S., or about 3.3 pounds per person per year.
What makes pesticides such a successful business is that the use of
pesticides generates the need for more pesticides and for new
pesticides. Pesticide users literally get hooked on pesticides, just
the way crack users get hooked on crack.
When a pesticide is sprayed onto a group of insects (or pests of any
kind, such as rats), most of the target pests are killed but a few
hardy ones survive. These hardy ones reproduce. Their offspring inherit
the ability to withstand attack from the particular chemical that
killed their parents' friends. If these offfspring get dosed, many of
them die but, again, the hardy ones survive and reproduce. Their
children are even more resistant to attack from that particular
chemical. As time goes on, a population of pests emerges that is
completely resistant to that chemical. Under some circumstances, pests
develop who actually thrive on the chemical, growing fat on the poison.
Between 1950 and 1980, nearly 500 important insect pest species have
developed genetic resistance to one chemical or another and now at
least 20 pest species are resistant to all widely-used insecticides.
According to the textbook Environmental Science by G. Tyler Miller,
"It is estimated that by the year 2000 virtually all major insect pests
will show some form of genetic resistance." In addition to insects,
genetic resistance has developed in 80 species of weeds treated with
weed-killers, 70 species of fungus treated with fungicides, and 10
species of rats treated with various rat poisons.
The development of genetic resistance cannot be stopped. It is in the
nature of pests and chemical poisons that genetic resistance will
develop among a species that is dosed repeatedly.
(At this point one might ask, why won't humans develop resistance to
toxic chemicals in the environment? The answer is, they will, but
remember: the development of genetic resistance carries a great cost--
the vast majority of the dosed population is killed or fails to
reproduce. The hardy survive but the process of developing genetic
resistance is exceedingly costly to a species. Breeding chemical-
resistant humans by dosing us all with low levels of toxins is like
trying to develop a strain of humans resistant to radiation by
spreading radioactivity into the environment at damaging levels. It
might have the desired genetic effect but civilization would end.)
When a species develops resistance, the farmer must either (a) increase
the dose next time; or (b) use a new poison next time. Thus the use of
pesticides creates the need to use more pesticides and new pesticides
to accomplish the original goal of controlling pests.
Fortunately, there is now real hope that pesticide addiction can be
treated. Much recent evidence indicates that the benefits of pesticides
have been greatly exaggerated and that farmers can achieve good crop
yields and can even earn an adequate income using low-pesticide or no-
pesticide farming methods.
For example, according to Tyler Miller, between 1940 and 1984, crop
losses to insects increased from 7% to 13% even though there was a 12-
fold increase in use of insecticides during the period. Corn losses to
insects more than tripled from 3.4% to 12% between 1945 and 1985
despite a thousand-fold increase in insecticides used on corn crops.
In April, 1991, a new study confirmed some of these conclusions. Here
is how the NEW YORK TIMES reported it:
"American farmers have long maintained that using fewer pesticides
would result in greater crop losses and increased food prices. But a
comprehensive analysis of the benefits and costs of the present heavy
dependence on chemical methods of pest control suggests otherwise.
"Yields would not decline and food prices would rise less than 1
percent if half the chemicals now applied on crops were replaced by
other control techniques, Cornell University researchers have concluded
after reviewing data on crop yields and pesticide use from hundreds of
scientists at university laboratories and Government agencies.
"[The study was directed by Dr. David Pimentel, professor of insect
ecology and agricultural sciences in the College of Agriculture and
Life Sciences at Cornell University.] Dr. Robert Metcalf, an
entomologist at the University of Illinois, said, 'If anything, Dr.
Pimentel's estimates are conservative,' adding 'Largescale pest
management studies have shown that pesticides could be reduced by half,
three-fourths, even ninety percent in some cases without adversely
affecting yields or the cost of food.'...
"Currently... about 45,000 people each year report accidental
poisonings by pesticides and, the [U.S.] Environmental Protection
Agency estimates, 6,000 Americans, most of them farm workers, are
afflicted with pesticide-induced cancers [each year]....
"Furthermore, the findings suggest, heavy dependence on chemicals to
control weeds, crop diseases and insect infestations long ago reached
the point of diminishing returns. Since the 1940s, there has been a 33-
fold increase in the amount of pesticides used and at least a 10-fold
increase in their potency, but 37% of crops are now lost to pests, up
from 31 percent in the 40's.
"'In 1945, when all corn was grown in rotation and no insecticides were
used, only 3.5 percent of the crop was lost to insects,' Dr. Pimentel
said in an interview. 'But today, corn is the largest user of
pesticides in the nation and 12 percent of the crop is lost to insects,
which indicates that the loss of crop rotation has been counter-
"Even under ideal conditions, only half the chemicals sprayed on crops
from aircraft lands on the target area. And with the new ultralow-
volume spraying, only 25 percent hits the target; 75 percent goes into
Good evidence now reveals that most pesticides are not needed. Thus the
way is clear for pesticide addicts to break free from the circle of
 G. Tyler Miller, Jr., ENVIRONMENTAL SCIENCE. Third Edition
(belmont, Ca: Wadsworth, 1991), pgs. 313-317."
 Miller, cited above, pg. 316.
 National Research Council, ALTERNATIVE AGRICULTURE (Washington, DC:
National Academy Press, 1989).
 Jane E. Brody, "Using Fewer Pesticides Is Seen As Beneficial," NEW
YORK TIMES April 2, 1991, pg. C4. See David Pimentel and others,
"Environmental and Economic Impact of Reducing U.S. Agricultural
Pesticide Use," HANDBOOK OF PEST MANAGEMENT IN AGRICULTURE Vol. I (Boca
Raton, FL: CRC Press, 1991), pgs. 679718.
WORKSHOP ON GRASS-ROOTS NEWSLETTERS
Environmental Research Foundation and the Environmental Health Network
of Harvey, Louisiana, will co-sponsor a workshop for writers and
editors of grass-roots newsletters, entitled "Writing for Environmental
Justice: The First Grass-roots Newsletter Workshop," September 7 and 8
in Washington, DC. We have organized the workshop as part of our
commitment to helping grass-roots groups USE information effectively.
The two-day workshop will cover such topics as: layout, production,
writing, editing and gathering information.
We are pleased to announce that the Environmental Support Center
(Washington, DC) will provide a number of travel scholarships to
individuals in state and local grass-roots groups wishing to attend. If
you want to attend the workshop or want information, please call Maria
Pellerano at (202) 328-1119.
Descriptor terms: pesticides; chemical industry; us; genetic
resistance; fungicides; insecticides; rodenticides; toxic substances;
crops; corn; new york times; agriculture; cornell university; david
pimentel; studies; robert metcalf; il; costs; epa;