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Date: 13 Aug 2003
Posted by: Michael Gochfeld (gochfeld@eohsi.rutgers.edu)

No Place for DDT

As a child growing up in Westchester County NY in the 1940's-1950's I 
benefitted from the weekly
spraying of DDT in our suburban community---no more mosquito bites 
(also no more butterflies, I
published a note on this many years ago).

Within a few years, however, the use of DDT lost its efficacy due to 
resistance.    A pesticide
that is very potent at killing is also very potent at selecting for 
resistance.  Our community
switched to other sprays which for some reason were kept secret, and 
we didn't know then to ask.

As an ecotoxicologist in the mid 1960's I was among those who 
documented the pervasive effects of
persistent organochlorines (DDT was just one of many) on avian 
reproduction.  This was the
original endocrine disruptor.  These compounds showed 
bioamplification, hence the impact on the
highest level predators (Peregrine, Bald Eagle, Osprey etc) was most 
profound.   I also suspect
that DDT eliminated many populations of non-target insects; our 
research for BUTTERFLIES OF NEW
JERSEY led to this conclusion---some species that were common in the 
1940's were not encountered
a decade later.  The subsequent Gypsy Moth campaigns added to the 
list of "former" resident
species.

As a provincial public health officer in Viet Nam in the late 1960's 
I was responsible for
malaria and plague control.  We dusted houses (and children with DDT 
in Talc).  Mosquito counts
on walls showed that there was already substantial resistance, even 
though the DDT had been used
there for only a few years.

For an engaging and reasonably objective history of DDT, and its 
introduction by Fred Soper, I
recommend ãThe Mosquito Killer,ä The New Yorker, July 2, 2001: 
QUOTED FROM SOME WEB-BASED
REVIEW:  "Malcolm Gladwell tells a riveting and eye-opening story 
about Fred Soper, whose
missionary zeal was in great part responsible for bringing DDT to the 
developing and developed
world during the 1940s and 1950s. This was all before 1962, when 
Rachel Carsonâs Silent Spring
revolutionized the way we look at pesticides. It is worth remembering 
that before DDT came to be
viewed as an environmental villain, it was widely considered a public 
health miracle. Malaria hit
85 percent of the U.S. soldiers defending Bataan in World War II — a 
more formidable opponent in
some places than enemy soldiers, as louse-borne typhus had been in 
World War I. The U.S. military
was among the first to rush DDT into use. Most fascinating is the 
personality of Fred Soper,
whose global public health campaign under the Rockefeller Foundation 
was prosecuted with military
zeal. His goal was nothing less than the global eradication of 
malaria. He almost succeeded. The
article stands as a reminder of how todayâs concerns about 
insect-borne diseases like West Nile
are trivial compared to the killers that DDT vanquished."

It is possible that if resources had been unlimited and political 
will unbending, malaria might
have been eliminated, if mosquito populations could have been reduced 
below a critical point.
However, once resistance became apparent, DDT rapidly lost its 
efficacy and charm----although not
its proponents.

Since DDT has NOT been used in many decades in the U.S. it is likely 
that resistance would have
disappeared, so efficacy is probably not an issue for the first year 
or two.  But the statistics
don't seem to warrant a radical approach.

And, as I predicted several years ago (and was evident in Europe), 
after an epidemic passes,
there are shadow epidemics in subsequent years.  It is likely that 
WNV  will become an indolent
disease with sporadic outbreaks.

Let's invest in some real public health issues like the burgeoning 
childhood asthma problem.   Or
even adult asthma/bronchitis.

Michael Gochfeld

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