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are based on a small class of chlorinated chemicals of which a few are pesti-
cides and have been removed from the market long ago. No one is implicating
the bulk of pesticides that are actually used in agriculture today.
I do not want to belittle the importance of this debate and its possible eco-
logical manifestations. It must be stressed that scientists are not suggesting
that pesticides chemically unrelated to chlorinated hydrocarbons would ever
have this activity, yet all media reports use the generic term pesticides in
their titles. Even for the pesticides that could have this action, such as DDT, it
may only occur at high doses. The reader should not be concerned that eating
produce with a minute amount of pesticides would ever produce these effects.
I believe this is an ecological issue that should not be confused with the topic
of this book.
In conclusion, I hope the reader appreciates that, despite the complete lack
of evidence that trace levels of pesticides in produce are harmful to the con-
sumer, the issue will never die. Whenever a new toxicity is described or a new
syndrome remotely related to pesticide use is reported, the alarm is sounded,
SOME REAL ISSUES IN CHEMICAL TOXICOLOGY 109
the anxiety level in the public increases and hysteria sets in. Regardless of how
low they are, whenever pesticide levels are detected in produce, baby food, or
some other product by a consumer or environmental group, the litany of
potential pesticide toxicities, ranging from cancer to estrogen problems, is
sounded, making people afraid and confused. Will this hysteria ever end? We
are at the dawn of a new millennium. Let us use science to continue improv-
ing our lives and not allow hysteria to ban effective tools that have visibly
aided public health, lest we revisit our earlier preindustrial existence marked
by famine and truly devastating plagues.
A truth that s told with bad intent
Beats all the Lies you can invent.
(William Blake, Auguries of Innocence )
Chapter
8
Milk Is Good for You
The previous chapters have discussed examples of detecting the presence of
certain classes of chemicals in foods. These chemicals, under some laborato-
ry conditions, were reported to have produced adverse biological effects in
animals. We were dealing with chemicals that at high doses or prolonged
exposures were actually capable of producing toxicity. The problem of assess-
ing their safety in food was one of establishing relative risks because of the
extremely low levels of exposure. We were introduced to a class of com-
pounds, the pesticides, which had dangerous relatives such as DDT in their
family tree. Even if the new generation of pesticides was significantly better
behaved because of lower usage rates, decreased environmental persist-
ence, and reduced toxicity to man, their family history was always being
dredged up to haunt them!
Let us change perspective and leave the arena of the organic chemical pes-
ticides. Instead, let us look at a recent example of the introduction of a differ-
ent type of drug into our food supply. This drug, by every scientific and med-
ical standard imaginable, is absolutely safe to humans consuming it. In fact,
there is so much species selectivity in its actions that the compound is not
active in humans even when it is injected directly into the bloodstream. In
contrast to some pesticides, it does not produce adverse effects in the labora-
tory. Since this drug is a member of an entirely new class of compounds, it
shouldn t have a bad family reputation to haunt it.
However, the development of this veterinary drug illustrates one of the
clearest examples of public misconception and hysteria thrust upon society in
recent years. This event was the November 1993 introduction of Monsanto
111
112 CHAPTER 8
Company s recombinant bovine somatotropin (BST) into the veterinary food
animal market. BST, also known as bovine growth hormone, rbST, rbGH,
sometribove, and Posilac®, is a drug designed to increase milk production in
dairy cows.
There is no medical or scientific basis for human health concerns when con-
suming milk from BST-treated cows. Normally, new drugs intended for use in
food-producing animals are approved by the FDA without a whimper from
the national news media. But BST was different, and it continues to generate
a storm of protest. Some states have even passed laws challenging the FDA s
authority to label and regulate drugs.
Why is BST so special? BST is a genetically engineered peptide produced
by bacteria using recombinant DNA technology. Thus it became the first
product of biotechnology to reach the American table. Its absolute safety is
best documented in a quote from a study conducted by the Office of
Management and Budget (OMB), of the executive branch of the federal gov-
ernment in January 1994.
There is no evidence that BST poses a health threat to humans or ani-
mals. It has been studied more than any other animal drug, and has
been found safe by FDA and many other scientific bodies in the U.S.,
Europe, and around the world. FDA also concludes there is no legal
basis requiring the labeling of BST milk, since the milk is indistin-
guishable from non-BST milk.
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