Risk: A Practical Guide for Deciding What's Really Safe and What's Really Dangerous in the World Around You - Softcover

David Ropeik has served as Director of Risk Communication at the Harvard Center for Risk Analysis. He was an award-winning journalist for two decades.
 

INTRODUCTION

"I"ve developed a new philosophy . . . I only dread one day at a time."
— Charlie Brown

We live in a dangerous world. Yet it is also a world far safer in many ways
than it has ever been. Life expectancy is up. Infant mortality is down.
Diseases that only recently were mass killers have been all but eradicated.
Advances in public health, medicine, environmental regulation, food safety,
and worker protection have dramatically reduced many of the major risks
we
faced just a few decades ago.
Yet new risks have arisen. Hazardous waste. Nuclear power.
Genetically modified foods. Mad cow disease. Ozone depletion. Artificial
sweeteners. For all the unquestionable benefits of the modern technological
world and its scientific power, the march of progress that has given us
longer,
healthier lives has subjected us to new perils.
We often react to this conflict, of progress on the one hand and
risk on the other, with fear. Most of us are more afraid than we have ever
been. And not just from any single risk that happens to be grabbing the
headlines at a given point in time, whether it"s terrorism or West Nile virus.
We are afraid, cumulatively, of all the new bogeymen to which our modern
existence has exposed us. Many polls find that people feel the world today
is
more dangerous for humans than it has ever been.
It is true that the industrial and information ages have spawned a
whole new range of risks, and raised awareness of those that were lurking
all
the time. But research suggests that our fears may not match the facts.
We
may be too afraid of lesser risks and not concerned enough about bigger
ones. Polls show a wide gap between what the public and the "experts"
think
is actually dangerous and what is considered relatively safe. Who"s right?
There are no simple answers.
But information can help us begin to sort things out. Some basic
facts about the risks we face, or think we face, can help us make more
sense of just what we need
to worry about. The intent of this book is to provide that information. We
want
to empower you to make better judgments about how to protect yourself
and
your family and friends. Our goal is to help you put the risks you face into
perspective.

Risk issues are often emotional. They are contentious. Disagreement is
often
deep and fierce. This is not surprising, given that how we perceive and
respond to risk is, at its core, about nothing less than survival. The
perception of and response to danger is a powerful and fundamental driver of
human behavior, thought, and emotion.
In writing this book, we tried to stay as neutral about these
controversial issues as we could. We think that information devoid of
advocacy is a tough commodity to come by these days, and will be more
useful to you. We do not tell you what you should think. Nor do we make
judgments about whether a risk is big or small for you as an individual. We
offer numbers for society as a whole, but there is no overarching single
conclusion about any risk that can be drawn for each reader. Each of you
has unique circumstances that make any given risk higher or lower for you
than it might be for the next person. Ultimately, how you perceive a given
risk
is a decision for you to make in the context of your own life. We simply
hope
that you are more able to make more informed choices after reading the
information we present. As Arthur Conan Doyle wrote in The Hound of the
Baskervilles, "That which is clearly known hath less terror than that which is
but hinted at and guessed."
We have gathered and analyzed the basic information available on
major risk issues and synthesized from all that research a fair presentation
that you can use to make up your mind about the risks we examine. Of
course we have made judgments along the way, about which risks to
include
or omit, about what information to offer and what information to leave out.
But
we have done so in an honest effort to get to the basic core truths about
each
risk as we see it, in as fair a way as possible. You may well disagree with
some of the judgments we"ve made. That"s a risk we run in taking on a
subject fraught with so much emotion.
We encourage you to use this book in two ways. Reading it all
the way through will let you see how each risk compares with the others
and
will help you put them all in perspective. There are a lot of statistics in this
book. They are provided to give you an idea of how big or small each
individual risk might be. But they will also let you compare similar statistics
for various risks from chapter to chapter. Together, these numbers should
help you gain a larger view of many of the risks you face.
But we also encourage you to use this guide as you would an
encyclopedia, as a reference work you will turn to over time, whenever
there"s
something about a particular risk you want to know. Each chapter, for
example, begins with a useful explanation of the specific hazard: What is
radon? How do air bags or nuclear power plants or cell phones work? What
are the most common forms of sexually transmitted or food-borne
diseases?
We hope this book remains valuable to you for some time. Yes,
the numbers of victims for various risks may change from year to year, and
we will certainly learn more about some risks than we know now. But the
nature of the consequences of alcohol consumption or radon exposure will
stay the same. Years from now the use of caffeine, the prevalence of heart
disease, the mechanics of the way radiation or lead or pesticides affects
us,
will all be pretty much the same.
We also hope you find this book useful no matter where you live.
While the numbers and exposure patterns we cite are focused on the
United
States, the details of most of the risks we explain are the same in Europe
or
Asia or South America. The effects of mercury, the science of genetic
modification of food, the persistence of some chemicals in the environment,
the way X rays work, are the same whether you live in Canada or France or
Japan. We recognize that the relative scale of risks varies from place to
place. The public health risk from cigarette smoke, for example, is higher in
Europe, where more people smoke, than in the United States. Firearms
risks
are higher for U.S. residents than citizens of any other country. At the time
of
this writing, mad cow disease is a higher risk in some nations than others.
So the data we use for exposure levels and numbers of victims, based on
statistics for the United States, may well vary for citizens of different
countries. But the general explanations of many of the risks we explore are
applicable for anyone, anywhere.

WHAT IS RISK?
Of all the wonders that I yet have heard,
It seems to me most strange that men should fear;
Seeing that death, a necessary end,
Will come when it will come.
— William Shakespeare, Julius Caesar

An anonymous writer once observed, "To risk living is to risk dying." Risk is,
indeed, inescapable. But just what is risk? How do you define it? To a
stockbroker it means the prospect of losing, or making, money. Same thing
for a person at the racetrack or at a blackjack table. For a skier or a bungee
jumper or a skydiver, on the other hand, risk has more to do with physical
than fiscal health. To the person taking a pill with known side effects, it"s
about choice. To the person eating food with potentially harmful ingredients
that aren"t listed on the label, it"s about no choice.
At it"s simplest, risk is the idea that something might happen,
usually something bad. But within that simple notion are some important
components that you need to understand in order to have a better basis on
which to make your personal risk judgments.
You may be hoping that this book answers the common question
we all have about most risks: "What are the chances that . . . ?" If you are
like most people, you think that risk means probability, the likelihood that
something will happen, as in "Your risk of dying from X is one in a million."
But there is more to risk than just calculating the statistical chances of a
certain outcome.
There is also the issue of consequences, as in "The likelihood of a
nuclear plant meltdown may be low, but it"s a risk because it"s disastrous if
it
does happen." A full definition of risk must take into account not just the
probability of an outcome, but its severity. Generally, risk involves an
outcome that is negative. You might say, "The odds of winning the lottery
are . . ." but you wouldn"t say that winning the lottery is a risk. And the
more
severe the outcome, the higher we judge the risk to be.
A complete definition of risk must also include the presence of a
hazard, as in "That compound is a risk. It causes cancer in lab animals." If
something to which we"re exposed isn"t hazardous, it isn"t a risk. We"re all
exposed to a lot of cotton in the clothes we wear. So what.
Which brings up the fourth major component of risk, exposure, as
in "Flooding isn"t a risk. I live on a hilltop." If a substance is harmful to test
subjects, but we"re never exposed to it, it doesn"t pose a risk. The risk of
being eaten by a shark doesn"t exist in Kansas. A hazard can"t do you any
harm if you are out of harm"s way.
So a more complete way of thinking about risk might read: Risk is
the probability that exposure to a hazard will lead to a negative
consequence.
It"s helpful to keep all these elements in mind when thinking about
risk. Take out any one of those components, and the definition is
incomplete.
Each one involves characteristics that help you understand risks more
completely and keep them in clearer perspective.
As an illustration, let"s consider that dreaded common risk:
ketchup. If we are exposed to ketchup, that exposure alone doesn"t make it
a
risk. As far as we know, ketchup isn"t a hazard, except for the chance of
spilling some on your clothes.
But let"s say somebody discovers that ketchup is hazardous. It
still isn"t much of a risk if the consequence of exposure to this hazard is,
say, an increased taste for pickles on your hamburger. The nature and
severity of the consequence has a lot to do with judging whether a risk is
big
or small.
But let"s say that you"re allergic to pickles, so anything that
entices you to eat them could indeed be dangerous to your health. Ketchup
still isn"t much of a risk if the probability of its leading to increased pickle
consumption is one in a million. You may have exposure to a hazard, but
the
level of risk still depends on the likelihood, the chance, that a negative
consequence might occur.
In other words, we can make better judgments about how to think
about risks if we keep in mind the ideas of hazard, exposure, consequence,
and probability. These characteristics help to define and explain the risks in
this book. Accordingly, most chapters are laid out as follows:
The Hazard: Just what is the agent we"re talking about? (What is
asbestos?) How does this hazard come to be in the world around us? (How
does mercury get into our fish?) What is the biological or physical
mechanism by which the hazard does its supposed harm? (How does
radiation affect us?)
The Range of Exposures: How are we exposed to this risk?
Where? When? How do exposures vary over time, by location, or by
population subgroup?
The Range of Consequences: How much harm does the hazard
do? In what ways? To how many people? To what kinds of people? Who is
most at risk? Is the harm short-term or long-term, fatal or not? What is the
probability of harm? How many people are injured or killed by the risk?
Reducing Your Risk: In this section we offer some general
suggestions about what you can do to minimize the risk we"re discussing.
For More Information: Each chapter ends with a list of resources
to provide you with more information.
Perhaps the biggest risk we take as authors is offering our
perspective and judgment of whether the risk is big or small, with visual
guides at the beginning of each chapter. This estimate is our best effort to
synthesize what we"ve learned on your behalf and to give you our opinion.
You will find two "risk meters" in each chapter. One will offer our
assessment
of the general likelihood of exposure to hazardous levels, taking into
account
the factors of exposure and hazard from our definition. The other meter will
indicate our assessment of the risk"s consequences—including severity
and
number of people affected.
Here are a few examples of what you will see in each chapter. At
the beginning of Chapter 1, "Accidents," the first risk meter will look like
this:
The upper bar indicates that the likelihood of exposure to accidents in a
way
that will probably cause harm is high. The lower bar indicates that the
consequences of the risk of accidents—the severity of the outcome and
how
many people suffer these consequences—are also high. But not quite as
high as the first meter, because the majority of accidents are not fatal, so
the
severity of the consequences brings the rating down a bit.
Here"s what the meter will look like for Chapter 35, "Radon."
The likelihood of exposure to levels that will probably cause harm is, in
general, pretty low. Lots of people are exposed, but the levels in most
cases
are fortunately not usually enough to cause harm. So there is exposure, but
not to levels that present a hazard in a lot of cases. But since the
consequences of radon exposure at levels high enough to do harm are
potentially severe, and several thousand Americans a year suffer those
consequences, the lower bar for radon takes account of both those factors.
These meters require several cautions. First, they refer to the
population as a whole. Your risk is almost certainly different from that of the
general population because of your age, gender, genetics, income,
education, location, and other factors that make you unique. These risk
meters offer only a general reference to where we think the risk falls on the
high-low scale. Second, these are estimates. They are not scientific. They
are the result of our analysis of the information we"ve collected and are not
statements of fact and truth. And since there is a lot of uncertainty about
many of the risks in this book, the meters are ballpark estimates that offer
only a general range of where we think the risk falls. That"s why we don"t
give
our ratings specific numbers between 0 and 10. (In Appendix 2 we discuss
our thinking behind each of the ratings. The appendix does offer our ratings
numerically, though some of them are given as a range rather than as one
specific number.)
Further, these risk gauges don"t take into account the benefits
that come from the hazard being discussed. Air bags can be harmful, for
example, but clearly they save many more lives than they take. Some
people
suffer serious side effects from vaccines, but vaccination"s benefits far
outweigh the risks. We leave that risk-benefit accounting out of our
judgment.
Since our definition or risk presumes that most ...