RISK
PERCEPTION
An
interesting article published in May on the Spanish blog "El ecologista
transgénico" (The transgenic ecologist) informs us about the perception of
risk by the public, and warns us against the enormous media pressure that we
suffer daily, with the sometimes mistaken perception of certain topics.
I'm very
interested in this article because agriculture, and in particular pesticides,
are among the targets most frequently affected by this problem, very often in
an unjustified way.
"Perception
of risk: a dangerous topic
May 12, 2018
Mistakes in the perception of risk
are the basis of many problems in the communication of science, so I will
dedicate this article to this topic, trying to clarify concepts through several
examples. Because every day, in our daily life, we must take an infinity of
decisions which are an exercise of balance between benefits and risks, some
unconscious, others more reasoned. Unfortunately humans are not very good at
assessing these risks. It greatly complicates our ability to make consistent
decisions, from medical decisions, more or less important, to the choice of
food we bring to our mouths.
In fact the evidence is clear, we
can't avoid these mistakes. Our apparent irrationality on these points is the
result of innate processes that operate outside of our conscious control. There
have been identified a number of emotional "fear factors" that make
some potential threats more fearful than others, unrelated to the obvious:
-
Risks
created by man scare us more than natural risks.
It is therefore likely that we are more frightened by transgenic crops,
radiation from nuclear power plants or chemical plants, than by
"natural" risks such as unpasteurized milk, natural medicines or
carcinogenic radiation from the sun.
-
We
are more concerned about risks we can't control and we tend to underestimate
risks we can control. For example we
overestimate the risk of glyphosate (or other phytosanitary products) but we
underestimate the risk of not eating enough fruits or vegetables, or sedentary
lifestyle.
-
Imposed
risks make us more afraid than those we voluntarily take.
For this reason, the perception of risk is greater in the case of radiation
from nuclear power plants than in the case of sun radiation, to which we
voluntarily expose ourselves.
-
We
are bad at assessing long-term risks and benefits.
We have an innate tendency to focus on the short term. For example, when
diseases such as measles or mumps disappear, the benefits of vaccination that
helped overcome them are no longer evident and can be questioned.
-
We
often forget to consider the risk of doing nothing, or the alternative.
These mental shortcuts and our
desire for simple answers about causality, risk, and benefit, lead to some
common mistakes in the way we act in our own lives.
Danger and
risk
Danger and risk are two different
but related concepts.
A danger is an agent that has the
potential to cause harm.
Risk measures the probability of
harm by a danger.
Dangers become risks only if there
is an exposition to it. Example: solar radiation is a danger. But if I never
expose myself (or protect myself) to radiation, I will not face the risk of
burns or melanomas, although the danger exists. Despite this difference, we
tend to consider all dangers as risks, regardless of our level of exposure.
This phenomenon is very evident in
the classification of IARC carcinogens (IARC http://monographs.iarc.fr/ENG/Classification/).
Danger identification is the first step
of the risk assessment, but it is not, in itself, a risk assessment, yet we
constantly see hazard identification studies presented as evidence of real
risks. These classifications are based on the strength of evidence and not on
the degree of risk. Two risk factors could be included in the same category,
although one increases the risk of cancer threefold and the other only
increases it by a small fraction. A good example could be tobacco and processed
meat, both included in category 1. According to Cancer Research UK (http://scienceblog.cancerresearchuk.org/2015/10/26/processed-meat-and-cancer-what-you
-need-to-know /), smoking causes 19% of all cancers. On the contrary, it is
estimated that "only" 3% of all cancers are caused by processed meat
and red meats combined. As a result, evidence that processed meat causes cancer
is as strong as that of tobacco, but the risk of tobacco is much higher.
All dangers
are not equal
As we have seen, not all dangers
are equal, they can affect a distinct number of people and be more or less
damaging. By observing the graph, we divide hazards into four categories based
on the number of people affected and the severity of the damage. The nature of
the product (natural or synthetic) has nothing to do with its dangerousness.
However, we sometimes tend to
consider that all dangers we pay attention to are as damaging as each other.
The development of the anti-vaccination movement shows this tendency to see all
risks as equal (considering the dangers of vaccination and the dangers of
diseases as equivalents in both gravity and risk of problem). The diseases that
are prevented by vaccination belong to the upper right-hand panel of the graph.
Vaccinations move the danger of these diseases to the left upper cadre by
significantly reducing the number of people affected by these diseases. On the
other hand, the vaccines themselves possess a generally low danger on a limited
segment of the population, which places them in the lower left-hand frame. Yet,
in many people's minds, the extremely rare risks (real or imagined) associated
with vaccines have become equal to or greater than the (real) risks of catching
the disease. The problem is the same for food additives.
Conclusion
We are permanently exposed to a
large number of dangers, some of which may pose a risk to our health if we
expose ourselves to them, if they are in excessive concentration or if they are
too frequent. Errors in the perception of risk are the basis of many problems
in the social communication of science. These errors are partly due to our poor
ability to correctly assess these risks (they can also be intentional). To
avoid them, we must evaluate each hazard separately, analyzing its damage
potential and level of exposure, as well as possible alternatives or the
consequences of avoiding it, to find out if something really represents a risk.
More information on this topic:
The confusion created around the
difference between danger and risk is carefully maintained, with a desired
objective, usually hidden, intended to favor sales or to provoke a change of
opinion or behavior.
This is
undoubtedly what has been happening for several years against conventional
agriculture, to promote the consumption of organic products. Those who
communicate in this way are capitalist companies that distribute organic food,
or environmental NGOs that try to attract new members, or to increase their
power.
This market
is very lucrative, and the means used to develop it don't hesitate to denigrate
everything that stands in its way.
Attracting the consumer by playing
on his fears is the only thing that matters.
And the collateral damage caused,
which is sometimes serious, does not matter.
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