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#491 - Shifting the Burden of Proof, 25-Apr-1996

For most of history, humans were so puny, compared to the rest of
nature, that the speed of technological change didn't matter. But since
1945, humans have become a major force that nature must reckon with.
Human activities now mobilize (pull from the deep earth and
redistribute into surface soils and water) much larger quantities of
many minerals than all the rest of nature put together. In other words,
humans dwarf the rest of nature when it comes to moving nitrogen,
phosphorus, sulfur, arsenic, mercury, lead, and a dozen other metals.
In addition, we have invented and dumped into the environment enormous
quantities of synthetic chemicals that nature does not ordinarily
create. As a result, we puny humans are changing the chemical balance
of the soils and waters of the entire planet. We are now waiting
(without paying close attention) to learn what effects these changes
will have on wildlife and on human health.[1]

As we saw last week, we are flying blind (see REHW #490). When we
deploy new chemical technologies (and genetic engineering
technologies), we have little or no idea what the consequences will be.
We learn about the consequences by trial and error, exposing wildlife
and humans and then waiting until harm becomes evident. Usually, we do
not even study the exposed individuals in any systematic way. Wildlife
may or may not be studied. In the case of humans, we almost invariably
wait until they notice symptoms in themselves. Then we generally ignore
them until they become desperately angry and get themselves organized
into a political force. Then we may begin to look for harm, using crude
techniques like epidemiology, which can only discover problems that
affect a large proportion of the study population.[2] Such studies take
years to complete; meanwhile exposure to the chemical continues. This
is the "prove harm" philosophy of public health protection and it forms
the basis of the public health system in the civilized world today. It
is not a philosophy based on prevention. Victims have to prove harm
before controls can be initiated.

After harm becomes evident, we may (or may not) take regulatory steps
to control the source of the problem. Although corporate polluters
complain bitterly that they are being strangled by environmental
regulations, in truth, all of the nation's environmental laws, taken
together, impose controls on only about 350 individual chemicals. There
are 71,000 chemicals in commercial use today, so our regulatory system
imposes controls on one-half of one percent of the chemicals currently
in use. In other words, 99.5% percent of chemicals are entirely

Under the "prove harm" pollution control system, the way we learn about
chemical problems is by unpleasant surprises. We learn after the fact
that we have begun to heat up the planet by our emission of greenhouse
gases. We learn after the fact that our refrigerators and air
conditioners have eaten holes as big as the United States in the
atmosphere over the north and south poles. We watch cancer rates
steadily rise and after about three decades of this, we begin to
scratch our heads. This is the way the "prove harm" public health
protection system works.

The most recent tidal wave of bad news has to do with hormones. The new
book, OUR STOLEN FUTURE, describes how scientists during this decade
have pieced together the latest threat to the well-being of wildlife
and humans: many industrial chemicals we have been dumping into the
ecosystem in huge quantities for years are now thought to interfere
with hormones.[3] (See REHW #263, #264, #486, #487, and #490). Hormones
are natural chemical messengers that flow through the blood stream,
providing chemical instructions that control growth, development and
behavior in birds, fish, amphibians, reptiles, and mammals, including
humans. No one knows how many of the 71,000 chemicals now in use can
actually interfere with hormones; so far, 51 chemicals have been shown
to have such an effect. The range of problems that may be caused by
hormone disruption is large: cancer, birth defects, confusion in sexual
preference (seen in wildlife and in laboratory animals), poor parenting
(seen in wildlife), stunted growth, reproductive failure, diminished
sperm count, endometriosis (a painful disease of the menstrual
tissues), ectopic (tubal) pregnancies, damage to the immune system,
impaired short-term memory, decreased ability to pay attention,
diminished intelligence, violent behavior--the list is long and
unpleasant. There is no doubt that hormone-related damage is occurring
in some wildlife populations. The case for damage to humans is less
firm; however, it seems certain that this is a serious problem that the
public health system must now gear up to define and then begin to

The main question raised by this most recent tsunami of bad news is
this: given that we are flying blind, what public policies could we
adopt that might reduce the number of unpleasant surprises we leave to
our children?

The problem breaks down into two parts: (1) what should we do about
existing chemicals? And (2) what should we do about newly-created

For existing chemicals, OUR STOLEN FUTURE offers some useful

** Greatly reduce the number of chemicals on the market. OUR STOLEN
FUTURE describes an effort to find environmentally benign chemicals for
use in the textile business. A group of researchers examined 7500
chemicals used to dye or process fabrics. They eliminated chemicals
that were toxic, persistent, mutagenic, carcinogenic, or known to
interfere with hormones. Of the 7500 chemicals, only 34 passed all the
tests. As a result, an environmentally benign fabric is now being

** Reduce the number of chemicals in products. Make products simpler.

** Make and market only chemicals that can be readily detected at
relevant levels in the real world with current technology.

** Restrict production to only products that have a completely defined
chemical makeup and disallow products containing unpredictable mixtures
of chemicals. Such mixtures --for example the 209 PCBs [polychlorinated
biphenyls] --are difficult to test for safety and to track after they
are released into the environment.

These are useful suggestions for altering our approach to EXISTING
CHEMICALS. But the issues involved are very complicated and hard for
most people to understand. A campaign to achieve these changes would
quickly bog down in debates between "dueling experts." The public would
be left out and would sleep through the debates. EXISTING CHEMICALS,
therefore, offer limited opportunities for initiating needed changes.

On the other hand, NEW CHEMICALS offer much greater opportunities.

** OUR STOLEN FUTURE points out (pg. 219) that we need to reverse the
burden of proof for safety of new chemicals. Presently new chemicals
are considered innocent until proven guilty. This should be reversed.
New chemicals should be assumed harmful until they have been thoroughly
tested for all the kinds of harm we presently know about. (This will
still not prove that any chemical is "safe" because history tells us
that, in the future, new kinds of harm will become apparent, and
furthermore we can never test for all the possible interactions between
existing chemicals and new ones.)[6]

Requiring that new chemicals be thoroughly tested, then banning the bad
ones, is the essence of pollution prevention. Despite this, most
corporate polluters --even those claiming to be green as grass --would
almost certainly oppose it. A campaign to make this one fundamental
change --to reverse the burden of proof for chemical safety --might
quickly reveal the amorality and the raw power of corporate polluters.
This would be a win-win battle, well worth taking on. Even if such a
campaign did not initially succeed in reversing the burden of proof, it
might lead to wider understanding that (a) corporations cannot reform
themselves and (b) that the corporate form itself will have to be
addressed before we can significantly improve chemical safety. (See
REHW #489, #488, #455, and #449.)

Strategically, it makes good sense to start with a campaign to reverse
the burden of proof for chemical safety. It is an issue that everyone
can understand. It's simple: if a chemical hasn't been thoroughly
tested, it's assumed dangerous and can't be manufactured. The morality
is clear: every baby has the right to be born free of poisonous
chemicals. No corporation has the right to chemically trespass, to
penetrate our bodies with poisons. Pharmaceutical drugs have to be
thoroughly tested before they can be sold; for the same reasons, all
chemicals should have to be thoroughly tested before they can be sold.
Who would oppose this change? Few people have anything at stake if a
chemical gets banned before it is ever manufactured. Therefore, most
people have no reason to oppose thorough testing of new chemicals. A
campaign to shift the burden of proof for chemical safety would starkly
expose the power relationship between the public and the corporate
polluters. Corporations campaigning for the right to release untested
poisons into the environment would be shooting themselves in the foot.

True, shifting the burden of proof for chemical safety would slow the
speed of chemical innovation --but that's part of the point. Evidence
accumulated during the past 25 years (see REHW #490) strongly suggests
that, when you are flying blind, you should fly more slowly than we are
presently doing. That way, even if you hit a mountain, there still
might be a chance for survival.

--Peter Montague


[1] For example, see Jerome O. Nriagu and Jozef M. Pacyna,
"Quantitative assessment of worldwide contamination of air, water, and
soil by trace metals," NATURE Vol. 333 (May 12, 1988), pgs. 134-139.
And see REHW #155. And see David L. MacIntosh and others, "Dietary
Exposures to Selected Metals and Pesticides," ENVIRONMENTAL HEALTH
PERSPECTIVES Vol. 104, No. 2 (February, 1996), pgs. 202-209.

[2] In principle, epidemiology can discern small effects, but this
requires studying large groups which, under most circumstances, is not

[3] Theo Colborn, Dianne Dumanoski and John Peterson Myers, OUR STOLEN
FUTURE (N.Y.: Dutton, 1996).

Vol. 103 Supplement 4 (May, 1995) devoted to the subject of "Wildlife
Vol. 103 Supplement 7 (October, 1995) devoted to the subject of
"Estrogens in the Environment." And see ENVIRONMENTAL HEALTH
PERSPECTIVES SUPPLEMENTS Vol. 103 Supplement 9 (December, 1995) devoted
to the subject of "Great Lakes and Human Health." ENVIRONMENTAL HEALTH
PERSPECTIVES is a peer-reviewed journal published by the National
Institute of Environmental Health Sciences (NIEHS), a federal agency.

[5] OUR STOLEN FUTURE, cited above in note 3, pgs. 226-229. To learn
more about the environmentally benign fabric, call Design Tex in New
York [(212) 886-8100] and request information about the McDonough

[6] Present tests are inadequate for defining the various kinds of harm
that are possible. To begin with, when a chemical is tested, its
metabolites and degradation byproducts should be tested as well. The
chemical and its metabolites and degradation byproducts should be
subjected to an improved battery of tests which would examine 3
generations of various animals species, with exposure occurring at
various times in the life of the first and second generations (because
the TIMING of exposure is critical for certain effects to be revealed).
The battery of chemical tests should be done in an uncontaminated
environment (as is present practice) but also should be done under
pseudo-realistic conditions, with the test animals simultaneously
exposed to various "background" conditions, such as farmers might
endure, or city dwellers, or workers in factories or in offices. By
this means, the interactions between a new chemical and existing
"background levels" of chemicals might be revealed. If any diminished
capacity or altered function in the nervous system, immune system,
endocrine (hormone) system or any organ system is revealed during the
full battery of tests, or if any disease condition or genetic damage is
initiated or promoted by the chemical being tested, of if the chemical
is persistent or bioaccumulative, (see REHW #378) then the principle of
precautionary action would be invoked: given that harm can be
reasonably expected or suspected, even before scientific consensus is
achieved the new chemical would be abandoned for commercial purposes.

Descriptor terms: technological change; biogeochemical cycles; prove
harm philosophy; pollution prevention; regulation; our stolen future;
hormone disrupters; endocrine disrupters; endocrine system;