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and chronic death. Acute death means the immediate occurrence of death due to an
overdose of a certain pollutant; chronic death accounts for health effects that lead
to a shorter life expectancy. In order to derive the number of life years lost due to
a fatal disease, statistics are used, especially from the WHO. These statistics can
show at what age and with which probability death occurs due to a certain cancer
type or respiratory health effect. Combining these statistics and the dose–response
and exposure–response functions (see Chapter 4), it can be calculated how many
years of life are lost due to the concentration increase of a certain pollutant.
The DALY concept includes not only the mortality effects but also morbidity.
Morbidity describes those health effects that do not lead to immediate death or to
a shorter period of life, but which account for decreased quality of life and for pain
and suffering. Cough, asthma or hospitalizations due to different pollutants refer to
this indicator. The morbidity health effects are expressed in years of disability (YLD).
Value choices must be made to weight the pain or suffering during a certain period
of time against premature death. Depending on the severity of the illness, suffering
and pain, the weighting factor for morbidity is between 0 and 1. A weighting factor
of 0.5 means that 1 year of suffering is supposed to be as severe as half a year of
premature death. The DALY indicator is, then, the result of the addition of both
indicators, with DW the relative disability weight and L representing the duration
of the disability:

DALY = YOLL YLD+ = YOLL + DW L⋅ (3.3)

Often a pollutant contributes to more than one health effect and a certain health
effect can lead to morbidity and mortality. Cancer, for instance, often leads to a
period of suffering and pain before death occurs and therefore contributes to YLD
and YOLL.
The value of YOLL or YLD does not depend only on the pollutant and the type
of disease. Because value choices are necessary for weighting, YLD and YOLL
strongly depend on the attitude of the person carrying out the weighting step. More-
over, a year of life lost at the age of 20 and a year of life lost at the age of 60 are not
equally appreciated in every socioeconomic perspective, according to the cultural
theory. For instance, one cultural theory discounts years of life lost in the same way
that discounting is done in finances. Therefore, a year of life lost in the future is worth
less than a year of life lost today. Another cultural perspective judges every YOLL to
be equally important independently of the age when it occurs (Hofstetter, 1998). If
one looks at the unit YOLLs, YLDs and DALYs, it can be said that the overall damage
for cancer is determined by mortality effects (YOLL), while morbidity effects (YLD)
can be neglected. For respiratory health effects, however, morbidity plays an important
role.

3.7.4 MONETIZATION OF ENVIRONMENTAL DAMAGES
Lately, acceptance of the approach of valuing health and environmental impacts in
monetary units for policy-oriented decision support, which is based on the theory
of neoclassical welfare economics, has been growing. In the U.S., cost benefit

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