PERCEIVED RISK AND THE SITING OF A CONTROVERSIAL ...

of the known probabilistic risk from dying from malaria to the probabilistic risk from
dying from DDT exposure would find a lower associated mortality with the later.
However, this comparison would not take into consideration the secondary impact on
avian species. Probabilistic risk also fails to consider that people may not respond to
objective risk rationally or consistently; people have been observed to respond
subjectively, emotionally, and dynamically. People have also been observed to not
respond to risk at all or to use cost benefit analysis to assess acceptable risk. Using the
previous example, individuals have been known to protest the use of wide spectrum
insecticides to eradicate mosquitoes on the grounds that sensitive human populations
will be negatively affected by neurotoxins. Yet others welcome the use of pesticides
because of the decrease in mosquito populations and consider the risk acceptable
What is considered acceptable risk? Tom Tietenberg (2006, p. 497), a resource
economist defines acceptable risk as “one that maximizes the net benefit” with net
benefit being defines as the “excess of benefits over costs” (2006, p. 22); in many cases
there is a time factor with both costs and benefits accruing into the future, therefore an
adjustment for time sensitive monetary values of benefits and costs may be applied.
Although objectivity is desired when evaluating acceptable risk, potential bias may be
present as it is difficult to identify all benefits and costs. Acceptable risk has been linked
to risk perception through three theoretical schools: the psychological, the cultural, and
the interdisciplinary.
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