March 2001
A Precautionary Approach to Toxic Chemicals
“In order to protect the environment, the precautionary
approach shall be widely applied by States according to
their capabilities. Where there are threats of serious or
irreversible damage, lack of full scientific certainty shall
not be used as a reason for postponing cost-effective
measures to prevent environmental degradation.”
Principle 15, Rio Declaration on
Environment and Development
“…Contracting Parties shall apply a precautionary
approach to environmental protection … whereby
appropriate preventative measures are taken when there
is reason to believe that wastes or other matter
introduced into the environment are likely to cause harm
even when there is no conclusive evidence to prove a
causal relation between inputs and their effects.”
Article 3, 1996 Protocol to the London
Convention on the Prevention of Marine
Pollution
Precaution, Policy, and Decision-Making
Precaution governs many aspects of daily life, from the
emergency services department that discharges
firefighters and ambulances (whether for burnt toast or
blazing buildings), to the natural resource agency that
bars the import of a predatory fish (that may or may not
endanger native species). Precaution responds to the
complexity of health and environmental problems and the
often-indeterminate nature of cause-and-effect
relationships. The principle was first enunciated as an
explicit basis of policy in German water protection law
during the 1970s. Known as “Vorsorgeprinzip,” or the
“foresight” principle, it has since guided a wide range of
policies, laws, and treaties addressing such issues as acid
rain, biotechnology, fisheries, radioactive waste
discharges, toxic chemicals, and climate change.
“In order to achieve sustainable development, policies
must be based on the precautionary principle.
Environmental measures must anticipate, prevent, and
attack the causes of environmental degradation. Where
there are threats of serious or irreversible damage, lack
of full scientific certainty should not be used as a reason
for postponing measures to prevent environmental
degradation.”
Bergen Ministerial Declaration on
Sustainable Development in the ECE
Region, 1990
The inclusion of the principle in the Rio Declaration at the
Earth Summit in June 1992 firmly placed precaution on
the global stage. Since that time, the principle has been
embraced in numerous international agreements including
the 1995 UN Fisheries Agreement, the Framework
Convention on Climate Change, and the Montreal
Protocol on Substances that Deplete the Ozone Layer.
More recently, the January 2000 Cartagena Protocol on
Biosafety reaffirmed the appropriateness of taking
protective action where there is a “lack of scientific
certainty due to insufficient relevant scientific information
and knowledge regarding the extent of the potential
adverse effects….”
The precautionary approach bids us to prevent harm
before it occurs. It states that where there is evidence that
an activity threatens wildlife, the environment, or human
health, protective measures should be taken even in the
absence of scientific certainty regarding the nature and
extent of the threat. Precaution stresses the importance of
prevention, the need for comprehensive and rigorous
inquiry, and the humility that comes with acknowledging
the enormity and complexity of scientific pursuit. Where
we can not pin down the exact nature and extent of health
and environmental effects, precaution directs us to
consider protective action -- based on the available
knowledge and research -- rather than wait years or
decades in hopes of a more precise answer.
The December 2000 United Nations Environment
Programme treaty to eliminate persistent organic
pollutants (POPs) includes explicit precautionary
references in the preamble, the objective, the section on
adding new chemicals to the treaty, and the determination
of best available technology. The objective states,
“Mindful of the precautionary approach as set forth in
Principle 15 of the Rio Declaration on Environment and
Development, the objective of this Convention is to
protect human health and the environment from persistent
organic pollutants.” The section on new chemicals says
that a “lack of full scientific certainty shall not prevent the
proposal from proceeding” and emphasizes that decisions
are to be made “in a precautionary manner.”
WWF embraces precaution as an overarching framework
that should inform every step of the decision-making
process, both for newly developed chemicals and for
those already in use. Precaution challenges us to study
every option and to consider substituting safe alternatives.
Precaution and Risk Assessment
Precaution provides an overarching framework for
addressing threats from toxic chemicals. Additional tools
such as risk assessment can provide useful input in the
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decision-making process, helping to sort out which threats
deserve priority attention. But the precautionary analysis
must go well beyond risk assessment. Though a valuable
tool in certain contexts, risk assessment has the potential
to narrow rather than broaden the analysis. In part this is
because risk assessment imparts a false sense of authority
and exactitude. Results are often expressed with a high
degree of precision, yet the adoption of divergent
assumptions and priorities in the appraisal may change the
conclusions by several orders of magnitude. Despite risk
assessment’s aura of scientific objectivity, political and
ideological preferences – often inserted throughout the
calculations -- can affect the outcomes radically. The risk
management emphasis on quantifying permissible levels
of health or environmental damage narrows the analysis
further, condoning acceptable harms even where safe
alternatives may exist or where benefits are derived only
by private interests. The precautionary approach, by
contrast, calls for review of the proposed action in light of
all the possible options and alternatives.
WWF Endorses Precaution
1.
Increasingly prominent in local and international
policies, laws, and treaties, precaution represents an
emerging principle of customary international law in
the context of high-stakes, low certainty
environmental decision-making.
2.
Precaution provides an overarching analytical
framework that should guide every step of the
decision-making process, from the earliest planning
stages to monitoring and evaluation of impacts.
3.
The precautionary approach revolves around
proactive analytical tools:
 vigilance in anticipating and preventing harm;
 assessment of alternatives;
 substitution; and
 research and monitoring.
4.
Additional tools such as risk assessment can provide
input in the decision-making process, but precaution
must remain the overarching analytic framework.
Adding uncertainty factors to a risk analysis may be
wise but does not take the place of a proactive
precautionary approach.
Toxic Chemicals Context
The WWF Global Toxic Chemicals Initiative endorses
precaution as an overarching framework for decisionmaking. This approach calls for rigorous scientific
inquiry into all relevant options and alternatives. It
promotes progress and productivity while protecting
wildlife, the environment, and human health. Precaution
should guide the review of both newly developed
chemicals and those already in use.
Serious or irreversible damage may be at stake.
Wildlife and people are regularly exposed to large
numbers of toxic chemicals, from mercury to dioxins to
brominated diphenyl ethers. Chemicals such as these
cause a range of adverse health outcomes including
cancers, immune and nervous system effects, and
impaired growth and reproduction. Not all of the
consequences are well understood.
For the many chemicals that persist and bioaccumulate, or
that are passed along through generations as “hand-medown” poisons, there is no turning back once unleashed in
the environment. This is particularly true in the case of
POPs and endocrine disrupting chemicals, two classes of
especially troublesome chemicals targeted for priority
attention by WWF. The precautionary approach is
needed to prevent serious or irreversible effects.
Some cause-and-effect relationships are not fully
established.
There is unequivocal evidence on many aspects of
chemical toxicity, but some questions remain elusive.
These include:
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the congruence of health effects in animals and
humans. To what extent does illness in laboratory
mice or rats, for example, suggest similar effects in
people?
the long-term impacts. What can short-term rodent
studies tell us about latent or chronic effects in
wildlife or humans?
the low-dose effects. If large doses of a substance
cause disease, what are the impacts of lesser
amounts? An increasing number of chemicals appear
to have effects at exposures not previously
considered harmful.
the interactive effects of exposures to multiple
substances. Laboratory studies usually test the
effects of single chemicals alone, yet generally we
are exposed to mixtures of multiple chemicals. What
is their combined effect?
the extent of non-cancer endpoints, from endocrine
disruption to immune system impairment. What are
the other health effects besides cancer? Research
remains insufficient.
Each of these concerns raises a series of complex
questions. For instance it is particularly difficult to
predict, based on animal studies, the effects on human
brain function from low level exposure to chemicals such
as lead or PCBs. And the conditions under which
exposures occur may affect outcomes dramatically; the
toxicity of polycyclic aromatic hydrocarbons to aquatic
species, for instance, may be increased significantly in the
presence of ultraviolet light. More generally, it is often
not possible to predict the effects of a chemical on all
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organisms from tests on a few selected species. Scientists
did not expect, for example, the harmful effects on
molluscs that have resulted from exposure to tributyl tin
leaching from the painted hulls of ships.
The case of plastics additives exemplifies the need for
precaution even where connections between cause and
effect are not crystal-clear. Manufacturers add chemical
softeners to increase the flexibility of many plastic
products such as food packaging, children’s toys, and
medical devices. With the recent unexpected discovery of
these chemicals in the general population, however, the
safety of the additives is increasingly becoming a
concern. Di(2-ethylhexyl) phthalate (DEHP), dibutyl
phthalate (DBP) and other common softeners have now
been implicated as a possible cause of adverse
developmental and reproductive effects. Prenatal
exposure to these chemicals appears particularly harmful
to male offspring -- laboratory animals and possibly
humans -- potentially associated with testicular atrophy,
reduced sperm count, structural deformities in
reproductive organs, or other outcomes. That the
mechanism, extent, and implications of possible effects
remain under investigation is no reason to postpone
removal of these chemicals from baby pacifiers, food
wrappers, nail polish, medical equipment, and other
products.
The lack of scientific certainty shall not be used as a
reason for postponing measures to prevent harm.
The knowledge that industrial chemicals are persisting in
the environment and concentrating in animal and human
tissue should be reason enough to look for replacements.
Even in the absence of scientific certainty, the threat of
birth defects, cancers, and other serious or irreversible
damage provides a compelling basis for precautionary
action.
Polar ecosystems have become a storage reservoir or
“sink” for pollutants traveling on wind and water currents
from temperate and tropical regions. In the Arctic, for
example, Inuit peoples and marine mammals have
accumulated dangerously high concentrations of PCBs
and other POPs in their body fat. Transferred to offspring
during fetal development and nursing, these contaminants
may be contributing to reproductive problems and
weakened immune systems. Likewise in Norway’s
Svalbard region, the heavy concentration of pesticides
and industrial chemicals found in polar bears may be
affecting immune function and reproductive success.
Elevated levels of persistent chemicals – as well as
immune system and/or fertility problems – are found also
in whales, seals, birds of prey, and other animals that are
high in the food web. That the cause-and-effect
relationships remain poorly understood is no justification
for a failure to act.
The Mechanics of Precaution
As noted earlier, the precautionary approach can best be
understood as an overarching principle that informs each
step of the decision-making process. In keeping with the
ideals of foresight and careful planning, the principle
places great weight on data collection and analysis. The
information-gathering process involves multiple sources,
including the public, to ensure that all relevant data are
considered.
The precautionary approach includes the following
elements:
(a) Vigilance in anticipating and preventing harm.
The precautionary approach calls for vigilance in
anticipating and preventing harm, acting upon early
warning signs even when scientific studies conflict or
do not give complete information. The evaluation
needs to consider both short- and long-term health
and ecological effects. Safety testing has its limits,
however. Even where initial tests suggest only
minimal hazards, ongoing vigilance is important to
recognize undetected dangers. Long-term monitoring
can provide information on synergistic outcomes and
unpredictable complex interactions.
(b) Assessment of alternative materials, products, and
processes.
To identify the response that best protects wildlife,
the environment, and public health, precaution entails
a thorough review of all relevant options, from no
action to goal-setting to phase out and elimination.
Many non-toxic substances and processes exist
today; others are within scientific reach.
The assessment of alternatives should not be limited
to chemical options. Clean production technologies
or organic farming, for example, can eliminate the
need for many toxic substances. Product or process
modifications can actually reduce manufacturing
costs, particularly those associated with handling and
disposal of hazardous chemicals, while protecting the
environment and public health.
(c) Substitution.
The precautionary approach calls for substituting
non-toxic or less-toxic alternatives in place of
dangerous chemicals. Sweden pioneered this
innovative approach in its Chemical Products Act.
The law directs companies to select the least harmful
chemical for a specified purpose and to strive to use
safer alternatives in place of hazardous chemicals
wherever possible. The substitution mechanism
drives the development of greener and cleaner
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production by assuring a market share for safer
products.
Corporate Responsibility and the Burden of
Persuasion
Like the Swedish law, the UNEP global POPs treaty
directs parties to consider substitution. Specifically,
Article D3(c) calls on parties to “Promote the
development and where it deems appropriate, require
the use of substitute or modified materials, products
and processes to prevent the formation and release of
chemicals listed in Annex C [on the registry of
byproduct POPs]…”
Objectivity and transparency are critical components in
each stage of scientific review, as are opportunities for
public input. Costs associated with the assessment should
be borne by the companies that stand to profit from the
chemical or technology. The proponent should accept
responsibility for generating information on options and
alternatives, making those data publicly accessible, and
ensuring that harm does not occur. Where damage does
result, the proponent bears responsibility for mitigating
the harm and providing compensation.
Where no safe alternatives can replace a dangerous
chemical, precaution calls for an additional review:
Who uses the substance? For what purpose? Who
benefits? What would be the consequence if the
chemical or product were no longer available?
Depending on the severity of the threat, the
irreversibility of the action, and the determination of
public benefit, the evaluation may lead to ultimate
elimination, product modification, or a range of
interim options such as education campaigns, product
labeling, regulatory standards, or research initiatives.
For severely hazardous substances and those that
bioaccumulate and/or persist in the environment, the
evaluation should result in prohibition or severe
restriction unless there is a clear societal need for the
chemical.
For example in the case of carbonless copy paper,
which conventionally was made with PCBs,
researchers have had difficulty identifying safe
alternatives with which to replace these dangerous
POPs. The fact that common substitutes such as
formaldehyde, xylene, and benzene are themselves
toxic should prompt a follow-up question: is
carbonless copy paper a product we cannot live
without? Toxic chemicals that meet important
societal needs but lack safe, effective, and affordable
substitutes should be placed on a fast-track for
research and development of alternatives.
(d) Rigorous scientific research.
The precautionary approach calls for rigorous
scientific research on chemical hazards, safe
substitutes, and clean production methods. It’s not
good enough to consider what is available currently –
what replacement could be developed is important
too. Precaution challenges us to design alternatives
that address societal needs without spawning harmful
consequences. The approach places great weight on
thorough scientific inquiry.
A reversal in the burden of persuasion should be utilized
to shift the starting point of analysis. Given the potential
for harm and the difficulty of remediation once a
chemical is “on the loose” in the environment -- and bioaccumulating in the food web -- potentially dangerous
substances should not be permitted without prior review.
This is particularly true for chemicals that are severely
hazardous, bioaccumulative, or persistent. It should be up
to the producers and marketers to show that the chemicals
are safe or that the societal benefits are so great as to
necessitate production and use.
Ultimately precaution is important not only for the
environment and public health but also for the bottom
line. The story of PCBs illustrates well how precaution
makes sound economic sense. Chemical company
executives were warned about serious health problems
from PCBs more than 60 years ago, but those early
warnings were not heeded. The chemicals were exported
to nearly every country in the world. Today, virtually
everyone has PCBs in their bodies. Corporations and
communities around the world face a complex multibillion dollar effort to replace old equipment, remediate
contaminated sites, and develop PCB destruction
technologies. Precaution would have prevented this
costly situation.
Global Toxic Chemicals Initiative
WWF International
Avenue du Mont Blanc
1196 Gland
Switzerland
Tel: +41.22.364.9111; Fax: +41.22.364.5829
www.panda.org/toxics
World Wildlife Fund
1250 24th Street, NW
Washington, DC 20037
Tel: +1.202.778.9625; Fax: +1.202.530.0743
www.worldwildlife.org/toxics
Email: toxics@wwfus.org