Environmental Engineering Reference
In-Depth Information
(motor vehicle accidents, suicide, poisonings) comprise the majority of causes
of death.
2
When a country shifts from predominately infectious disease mortality to
chronic disease mortality, the country is said to have undergone the
epidemiologic
transition
. Although this has been the view of disease burden for the latter half of
the twentieth century, the burden of chronic diseases in developing countries has
increased dramatically in the last two decades and has resulted in mixed patterns
of mortality between different populations, even within the same country. For
example, in developing countries relatively well-off urban dwellers will have a
higher mortality due to chronic diseases, while poor rural residents may have
greater burden of infectious disease. Therefore, it is important to remember that
while communicable diseases are the focus of this chapter and the next, individ-
uals with chronic health conditions will make up large proportions of infected
populations; this has large implications for the severity of disease and managing
clinical conditions, and it reiterates the importance of prevention for all.
A study by Clough
3
compares two investigations showing the impact of
environmental factors on cancer mortality. The term
environment
has different
meanings to the epidemiologist and to the general public. To the epidemiologist,
“it refers to everything that humans encounter: everything that is eaten, drunk,
and smoked; drugs, medicine, and occupational exposures; and air, water, and
soil. In this context it means everything outside the body as distinct from a
person's genetics.”
3
Clough defined “environment” as the aggregate of all the
external conditions and influences affecting the life and development of humans.
Included is the air, water, land, and climate and the interrelationship that exists
between them and all living things.
Social epidemiologists refer to different levels of human environment,
terms that may be used differently than in other realms of environmental
engineering. The
built environment
refers to manmade structures that are the
setting for human activity, including buildings, bridges and planned open spaces.
Influences of the built environment on mental health,
4
,
5
obesity,
6
nutrition,
7
sleep disturbances,
8
traffic accidents,
9
malaria-transmitting mosquitoes,
10
visceral leishmaniasis,
11
and other diseases and injuries have been documented.
Although causal inference between these associations is difficult to make, we
are just beginning to understand the health impact of the structures we live
and work in. This is likely to be an expanding and exciting field of research
in public health that can be translated into applications through environmental
engineering.
Social factors not intuitively associated with health can also have significant
influences. Of all the predictors of individual good health (diet, exercise, envi-
ronmental factors, access to medical care, etc.), studies repeatedly show that
educational attainment is highly important. More educated populations tend to
be healthier, although the causal mechanism has not been clearly articulated.
Although increasing the basic education level is not usually considered a public
health intervention, it should be acknowledged that many of the broader soci-
etal trends that influence health are beyond the scope of any individual agency
