Environmental Health News

What's Working

  • Garden Mosaics projects promote science education while connecting young and old people as they work together in local gardens.
  • Hope Meadows is a planned inter-generational community containing foster and adoptive parents, children, and senior citizens
  • In August 2002, the Los Angeles Unified School District (LAUSD) Board voted to ban soft drinks from all of the district’s schools

#705 - Modern Environmental Protection--Part 2, 02-Aug-2000

[Rachel's will now be published every other week; the name
has been changed to Rachel's Environment & Health Biweekly.--P.M.]

Is it merely by coincidence that the NEW YORK TIMES chose the
birthday of the United States -- July 4th -- to discuss the
metaphors that scientists are now using to describe the
destruction of the global ecosystem?[1]

What is the best metaphor to help us understand the accelerating
disappearance of animal and plant life and indigenous people
world-wide, including the U.S. where one-third of all animals and
all plants are now at risk of extinction and where the
destruction of indigenous people exceeded 90% some time ago?

** Is the best metaphor the airplane losing rivets? Many rivets
can pop out without having any effect on the airworthiness of the
plane, but eventually the loss of one-too-many rivets will cause
a crash.

** Or is it more appropriate to compare the global ecosystem to a
rich, diverse tapestry, a metaphor used by Carlos Davidson, a
conservation biologist at the University of California (Davis) in
an interview with TIMES staff writer William K. Stevens. "The
function and beauty of the tapestry is slightly diminished with
the removal of each thread. If too many threads are pulled --
especially if they are pulled from the same area -- the tapestry
will begin to look worn and may tear locally." In this metaphor,
there is no "crash," but rather a "continuum of degradation" from
"a world rich in biodiversity to a threadbare remnant with fewer
species, fewer natural places, less beauty, and reduced ecosystem
services." According to this metaphor, any crashes that may occur
(such as the collaps e of a fishery) are relatively rare and
local.

** But, says Stevens, even the tapestry metaphor seems
"incomplete" because "if the human impact on the rest of nature
is as pervasive and encompassing as many scientists say," then
humans are not just fraying the tapestry they are re-weaving it
in entirely new patterns which are "markedly simpler, duller, and
less functional than the original."

The main impact of humans is to simplify the Earth and
simplification itself leads to the danger of collapse, according
to G. David Tilman and Kevin S. McCann, both of whom recently
published articles on biodiversity in the British journal
NATURE.[2,3] Only during the past 10 years have scientists been
able to show that diversity is important to the stability of
ecosystems. David Tilman told William K. Stevens, "We're
simplifying the world on a mass scale, an unprecedented scale."

Tilman points out that we now know for sure that simplified
ecosystems are subject to collapse, and we see the tapestry
metaphor beginning to converge with the rivet metaphor. It is
diversity that allows an ecosystem to survive during times of
stress, such as drought. Because of diversity, drought will not
kill every part of an ecosystem, so there is something remaining
from which to rebuild. A grossly simplified ecosystem may not be
able to rebuild, and desert conditions (for example) may become
the norm. (An estimated 35% of the world's land is now threatened
by the advance of deserts.[4]) From a human viewpoint, simple
ecosystems can be very productive (farmer's fields of corn, for
example), but they are fragile and subject to collapse (for
example, the Irish potato famine of 1845-1851 killed a million
people). Thus even "local" collapse can be exceedingly painful
for those involved.

Humans are altering the face of the earth in three major ways,
according to Jane Lubchenco, former president of the American
Association for the Advancement of Science: (a) transforming the
land and the sea, through land clearing, forestry, grazing,
urbanization, mining, trawling, dredging, and so on -- all the
activities we call mis-label "development;" (b) adding or
removing species and genetically distinct populations via habitat
alteration or loss, hunting, fishing, and introductions and
invasions of species; and (c) altering the major biogeochemical
cycles, of carbon, nitrogen, water, and synthetic
chemicals....[5]

Probably the easiest of all these problems to solve is the
industrial contamination of the globe with exotic, dangerous
chemicals. Jane Lubchenco describes the problem this way: "Novel
chemical compounds -- ranging from chlorofluorocarbons to
persistent organic compounds such as DDT and PCBs -- are being
synthesized and released. Only a few of the thousand or so new
chemicals released each year are monitored; the biological
effects of most are unknown, especially synergistic interactions
of different compounds, and interference with developmental and
hormonal systems." Note that all of Lubchenco's examples are
chlorinated compounds -- ozone-destroying chlorofluorocarbons
(CFCs), DDT and PCBs. These are good choices because chlorinated
compounds tend to be toxic, long-lived, and incompatible with
ecosystems. Phasing out chlorine on a strict schedule -- the way
the world is trying to phase out CFCs through the Montreal
Protocol -- would be a rational step that humans could take to
reduce the destruction of the Earth.

The Chlorine Chemistry Council -- the association of corporations
that make and sell chlorinated chemicals -- argues that the world
should continue to regulate chlorinated chemicals one-by-one
using risk assessments, the regulatory status quo. They have one
main reason for advocating this position: they know it can never
lead to any significant curtailment of the chlorinated chemical
industry.

The only rational, protective policy would be to phase out all
chlorinated chemicals as a class. All of them. If any were to be
retained, they would be exempted from phase-out on a case-by-case
basis. In other words, the burden of proof should be shifted from
the public onto the chlorine-using polluters: they should have to
show that their wares are not causing, or going to cause,
significant harm.

In other words -- as Joe Thornton says in his excellent new book,
PANDORA'S POISON [6] -- before a substance can be introduced into
commerce, the manufacturer should have to show that the substance
and its associated by-products and breakdown products are neither
persistent nor bioaccumulative and that they are not
carcinogenic, mutagenic, disruptive of intracellular signaling
(by hormones, neurotransmitters, growth factors, cytokines, and
so on), or toxic at low doses to development, reproduction,
immunity, or neurological function. Very few organochlorines
could pass such a test. Thus, this would be entirely too great a
burden for the chlorinated chemical industry to bear, and they
know it. So they favor a continuation of the entirely ineffective
present regulatory system based on risk assessments chemical by
chemical, one at a time.

As Joe Thornton points out, there are seven reasons why
chemical-by-chemical regulation of chlorinated chemicals has
failed:

1) There are 11,000 chlorinated compounds created intentionally
and thousands more created unintentionally. Furthermore, new
chemicals are brought on the market much faster than
toxicologists can evaluate their hazards. As of the early 1990s,
EPA [U.S. Environmental Protection Agency] had established
effluent guidelines for 128 chemicals, had prepared health
assessments on fewer than 100 chemicals, and had issued air
emission standards for fewer than 10 chemicals. This is the
result of 30 years of intense effort. EPA's scientific
reassessment of the hazards of just one organochlorine chemical
-- dioxin -- has been underway since 1991 and is still in draft
form. Even if EPA were to assign vast new resources to the task
of evaluating the hazards of chlorinated chemicals, it would take
many, many centuries to complete the task.

2) Organochlorines are formed as complex mixtures of thousands of
compounds, and the great majority of chlorinated by-products
remain unidentified and unknown. I t is not possible to assess
and control on a chemical-by-chemical basis compounds that have
not been identified.

3) Even if our goal were to eliminate only the most persistent,
bioaccumulative and toxic organochlorines, the only practical way
to accomplish this would be to phase out all of them because
chlorine chemistry cannot be practiced without creating large
quantities of persistent, bioaccumulative and toxic by-products.
As Thornton points out, the continuing production of thousands of
tons of PCBs each year -- decades after the intentional
manufacture of PCBs was outlawed -- shows the failure of
chemical-by-chemical regulation. Dioxin is in the same class --
almost all chlorinated products and processes create dioxin
somewhere along the way -- so to avoid the production of this
most toxic of all chlorinated compounds, all chlorine chemistry
must be phased out.

4) The limits of toxicology and epidemiology make the
chemical-by-chemical approach unsuitable for protecting health
and ecosystems. Organochlorines occur in complex mixtures, so
toxicologists and epidemiologists will never be able to sort out
which chemical is causing which health effects because, as
Thornton says, "the fact is that groups of these compounds are
always responsible." "In contrast, a focus on the technologies
that cause organochlorine pollution eliminates the formation of
these mixtures, immediately dispensing with the problems of
unidentified compounds and synergistic effects," Thornton points
out. [pg. 351]

5) The fifth reason is economic: as society phases out one
organochlorine (for example, DDT), the chlorine industry creates
a market for another chlorinated product and thus maintains -- or
accelerates -- its program of global destruction. What the world
needs is a reduction in the total burden of chlorinated
chemicals, not just a reduction in one or two or 10 specific
compounds. Chemical-by-chemical regulation can never give the
planet respite from the chlorine scourge.

6) It makes no sense to presume that the thousands of untested
organochlorines are benign, given that virtually every
chlorinated compound ever tested causes one or more toxic
effects. Chlorination almost always increases the toxicity and
the bioaccumulation of organic chemicals. It is therefore logical
and consistent with existing knowledge to presume that all
chlorinated compounds are hazardous unless specific information
suggests otherwise.

7) The last reason for treating organochlorines as a class is
ethical. Chemical-by-chemical regulation assumes each chemical is
innocent until proven guilty. This places the burden of proof on
the public to prove that each chemical is harmful. As Thornton
says (pg. 353), the result is a vast, poorly documented program
of chemical experimentation on the public, "in which the
ecosystem and our bodies are contaminated by novel chemicals, the
effects of which are not well known, but are likely to be
harmful." People have a right not to be experimented on without
informed consent; no one has ever had the opportunity to grant or
deny their consent before being exposed to the organochlorine
burden that now contaminates us all." Joe Thornton is too
generous to say so, but the chlorophiles -- the lovers of
chlorine chemistry -- are imperceptibly different from the Nazis
of the Third Reich in their willingness to allow monstrous
experiments upon hapless, captive victims, world-wide.

--Peter Montague (National Writers Union, UAW Local 1981/AFL-CIO)

=====

[1] William K. Stevens, "Lost Rivets and Threads, and Ecosystems
Pulled Apart," NEW YORK TIMES July 4, 2000, pg. 4.

[2] David Tilman, "Causes, consequences and ethics of
biodiversity," NATURE Vol. 405 (May 11, 2000), pgs. 208-211.

[3] Kevin Shear McCann, "The diversity-stability debate," NATURE
Vol. 405 (May 11, 2000), pgs. 228-233.

[4] http://www.funkandwagnalls.com/encyclopedia/

[5] Jane Lubchenco, "Entering the Century of the Environment: A
New Social Contract for Science," SCIENCE Vol. 279 (January 23,
1998), pgs. 491-497.

[6] Joe Thornton, PANDORA'S POISON; CHLORINE, HEALTH, AND A NEW
ENVIRONMENTAL STRATEGY (Cambridge, Mass.: MIT Press, 2000). ISBN:
0262201240.