The Commission on Risk Assessment and Risk Management was
mandated by Congress in the 1990 amendments to the Clean Air Act
to address risks that are regulated under the many laws aimed at
protecting the environment and protecting the health and safety
of the American people from potentially dangerous exposures to
chemicals and other hazardous substances and objects in air,
water, food, the workplace, and consumer products. Of the 10
members of the Commission, 3 were appointed by the president, 6
by the majority and minority leaders of the House and Senate, and
1 by the president of the National Academy of Sciences.(1) The Commission's
mandate(2) is
summarized in the following phrases:
The Commission was also asked to comment on the conclusions of
Science and Judgment in Risk Assessment (NRC 1994a) (see
appendix A.3) and to make recommendations about peer review.
Congress decided to create the Commission when agreement could
not be reached, during drafting of the 1990 Clean Air Act
Amendments, on the best way for the U.S. Environmental Protection
Agency (EPA) to determine whether any significant risks to human
health will remain after technology-based controls are
implemented to reduce hazardous-pollutant emissions from
stationary sources and, if so, what to do about those residual
risks. There was disagreement about the risk-assessment
techniques and assumptions that should be used to estimate
residual risks, about the benchmarks that should be used to
distinguish between negligible and unacceptable risks, and about
the risk-management methods that should be used to mitigate
unacceptable risks. But the Commission's mandate was not
restricted to evaluating air pollution, the particulars of the
Clean Air Act, or the EPA. Rather, it was limited to "cancer
and other chronic human health effects," so we did not
address environmental problems, such as global climate change,
ozone depletion in the stratosphere, or protection of wetlands
and other habitats. We do note, however, that human health
depends on a healthy environment, that the general approaches of
health risk assessment are applicable to ecological risk
assessment, and that benefit-cost analyses should assess all
benefits, not just human-health benefits.
Through its deliberations, the Commission developed a shared
vision of sustainable goals for our environment, our economy, and
our society. Like the National Commission on the Environment
(1992) and the President's Council on Sustainable Development
(1996), we seek a convergence of economic and environmental goals
and actions. We recognize that special sensitivity is required to
encompass the diverse socioeconomic status and cultural practices
of this nation. We seek a comprehensive, risk-based approach that
puts specific actions in a public-health and ecological context.
As a result of public recognition of environmental problems
and translation of that recognition into effective action,
tremendous progress has been achieved during the last 25 years in
improving air quality, water quality, safety at work, safety of
consumer products (including drugs and foods), testing of new
chemicals before they are introduced into commerce, cleanup and
disposal of hazardous wastes, and scientific study of health
effects and ecological effects of chemicals, radiation, and
microorganisms. Improvements in public health historically have
come primarily from environmental interventions, such as proper
waste disposal and hygiene, quarantines, clean water, and
vaccines. Although many federal environmental laws share a
primary goal of protecting the public's health and the
environment, most environmental statutes have been media-specific
and have relied on regulatory approaches rather than
public-health approaches.
We know that the gains of the last 25 years can be sustained
only by continued action, especially as the economy and the
population grow and new technologies are introduced, and we
believe that the effort to sustain them will be most effective if
regulatory and public-health agencies work together.
Risk is a combination of the probability of an event--usually
an adverse event--and the nature and severity of the event. We
deal with risks all the time in everyday life--risks to our
health, our environment, our pocketbooks, our social
relationships. Risk is time-related, from immediate consequences
of various actions or lack of action to consequences over a
lifetime for an individual and much longer periods for the whole
society or the planet. We make decisions to avoid risks, to
reduce risks, to reduce the consequences of events, and to insure
against the financial consequences of risks. We tend to downplay
some risks; we find others frightening. Of course, people vary in
those assessments, and their actions or concerns tend to vary
accordingly. Often, the people who face specific risks are
different from the people who benefit from the events involved in
the risks, leading to conflict and litigation over proposed
actions. Risk assessment itself has become controversial because
of its important role in the protection of human health and the
environment.
A generally accepted framework and nomenclature for health
risk assessment was established in 1983 by a National Academy of
Sciences committee report, Risk Assessment in the Federal
Government: Managing the Process (NRC 1983). The now
universally recognized four-step framework for characterizing the
likelihood of adverse health effects from particular chemical
exposures is described briefly below and shown in the context of
scientific issues and regulatory impact in figure 1.1.
Figure 1.1 Elements of risk assessment and risk management

Source: Science and Judgment in Risk Assessment (NRC
1994a). Reprinted with permission.
The Commission was directed to focus on what Congress called
"chronic health effects", meaning effects that do not
occur immediately--like injuries from falling off a construction
platform--but that are the cumulative result of repeated
exposures that might take months, years, or decades to become
manifest as health problems. Risks from chronic exposures arise
from activities associated with the use and production of food,
energy, industrial and consumer goods, and from the wastes
produced through daily living. We recognize that voluntary uses
of specific consumer products are also major contributors to
death and poor health. Cigarette-smoking leads the list by a wide
margin, accounting for an estimated 400,000 deaths every year
(McGinnis and Foege 1993). Use of alcoholic beverages accounts
for about 100,000 deaths, and motor-vehicle collisions for about
25,000 deaths. As many as 60,000 deaths per year are estimated to
be attributable to airborne fine particles. Many activities
individually contribute little to overall public-health risks but
substantially when viewed collectively. For example, 60,000
deaths per year have been attributed to occupational and
environmental chemical exposures of all types.
Of all causes of death, the most salient for most people is
cancer; it is important to recognize that cancer has multiple
causes and is not a single disease. However, cancer is not the
only cause of health concerns associated with environmental
pollutants. Reproductive impairments, birth abnormalities, asthma
and other forms of airway hyperactivity, and effects on all the
organ systems of the body warrant serious attention from a
risk-management perspective. Even if those health effects have
modest impacts on mortality, they are important determinants of
our quality of life.
Risk assessment goes beyond scientific observations of
exposures and effects in people, animals, or test systems to try
to answer social questions about what is unsafe. There is a
difference between what can be studied experimentally or be
observed directly and what represents policy-driven extrapolation
based on scientific inferences and many assumptions. The 1994
National Research Council report Science and Judgment in Risk
Assessment captured this combination of science and values
in its title.
We face a huge challenge to manage comprehensively the health
risks associated with the vast array of pollution-generating
activities in this country. Our regulatory agencies are expected
to control, down to an extremely low level, the potential cancer
risks, for example, associated with each of those individual
activities; a limit of less than 1 extra cancer death from a
particular chemical per million persons exposed over a 70-year
lifetime is generally used for screening purposes and when
exceeded, might serve as a justification for seeking exposure
monitoring data to more accurately characterize risks. Risk
criteria used in regulating occupational exposure to specific
chemicals often correspond to about 1 extra cancer death out of
every 1,000 workers exposed over a working lifetime. For
noncancer risks, regulatory agencies aim to reduce exposures to
below presumed thresholds for adverse effects.
As directed by Congress and reinforced by the Clinton
Administration, we have framed our analyses and recommendations
from the perspective of risk management. How do we use the tools
of risk assessment and of economic analysis and consider social
and cultural information to make better, more-efficient,
more-understandable, and less-costly decisions about reducing
risks that are judged to be too high? How do we compare risks and
risk-reduction actions of various kinds to determine which
deserve higher priority? What are the community, public-health,
and environmental contexts for formulating a particular problem,
characterizing its risks, deciding what to do about it, and
evaluating the impact of actions taken? It is crucial to reach
out to affected parties and communities to obtain knowledge about
the nature of past and present exposures and to understand their
concerns and perceptions about the risks under discussion and
related risks. Communication about risks is a two-way process.
To address those questions, the Commission proposes a
comprehensive risk-management framework for making decisions
about reducing risks to public health and the environment. The
process includes detailed consideration of risk and cost and
provides a context for social and cultural considerations. One
salient feature of the framework is its explicit involvement of
stakeholders in decisions about how to reduce the risks that
affect them--through consensus or despite disagreement--depending
on the circumstances. Another salient feature is the integrated,
multimedia approach the framework takes to address multiple risks
instead of individual risks.
This report is the product of the Commission's deliberations
and evaluations since May 1994 and constitutes a response to
concerns of those who provided testimony before the Commission(3) and issue papers
prepared for the Commission by several experts.(4) Section 2 describes
the framework and its application, setting the stage for the rest
of the report. Sections 3 and 4 provide guidance on how to
approach the risk and cost components of the framework. Section 5
addresses ways to improve risk communication and risk management.
Section 6 provides recommendations for specific federal
regulatory agencies and programs.
This report is a draft intended to elicit public review and
comment. The draft and the reports abstracted in appendix A.5 are
available from the internet at http://www.riskworld.com. The
Commission welcomes written comments addressed to its office at
529 14th St. NW, Suite 452, Washington, DC 20045--preferably by
July 17, so that they can be considered in a public hearing on
July 23 in Boston, but as late as August 9, so that they can be
considered in the preparation of the final report. The
Commission's final report will be issued in October 1996 and will
be followed by additional hearings and presentations at meetings.
1Biographies of Commission members are provided in appendix A.1.
2A copy of the Commission's mandate is included as appendix A.2.
3A list of the persons who testified at Commission meetings is included as appendix A.4.
4Abstracts of the issue papers
prepared for the Commission are included as appendix A.5.