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4 Environmental Risk

Assessment

With the contribution of Montserrat Meneses

4.1 INTRODUCTION

This chapter deals with the typical concept of risk assessment as a fundamental basis
of environmental management. A general introduction of the risk concept is given
in the first part of the chapter and hazard identification is explained. Exposure
assessment and risk characterization for human health and ecological exposure are
described; also included is a description of environmental monitoring, as well as
general information about the fate and exposure models. Special emphasis is given
to the study of the dose–response and exposure–response functions and the human
health risk characterization for carcinogenic and noncarcinogenic risk. Some exam-
ples are introduced and different practical problems related to them are given at the
end of the chapter.
Another approach is also explained: the impact pathway analysis (IPA), which
is shown as an alternative way of analysis in cases for which risk assessment (RA)
results have to be converted into damage estimations.
IPA is used to assess the impacts produced by some of the processes of the life-
cycle of a process or service, with a higher level of detail than that obtained from
a conventional LCA. Because the impact caused by a pollutant emitted at a specific
site depends on site-specific parameters such as population density, meteorological
data, etc., the tools used by risk assessment, such as fate, transport and exposure
assessment, are included in the analysis. In this manner, risk assessment and LCA
can be linked.
IPA is presented in this chapter as an application of environmental risk assessment
(ERA) but with a huge potential for use within the life-cycle impact assessment
(LCIA). The IPA will be thus taken up again in later chapters for different applications,
development of methodology and examples.

4.2 RISK ASSESSMENT

The term “risk” has different meanings depending on different contexts. For a
layperson it embodies the concepts of severity and probability of outcome. For
example, people do not consider death by asteroid impact very risky, primarily
because the likelihood of such an occurrence is perceived to be very small. Similarly,
death from an accident or a fall at home is not appreciated as a significant risk

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