Biomedical Engineering Reference
In-Depth Information
(POPs), and nutrients (e.g., nitrogen and phosphorus), which have the capac-
ity to cause adverse health effects. Runoff from agriculture contains pes-
ticides, such as dichlorodiphenyltrichloroethane (DDT), chlordane, and
atrazine, that can heavily contaminate water bodies and enter the drink-
ing water sources. Pesticides can cause both endocrine and reproductive
health damages, and long-term exposure to some of them is carcinogenic
[8]. Inadequately treated municipal sewage can carry microbial pathogens,
causing the spread of diseases such as diarrhea or cholera. Domestic waste-
water, agricultural runoff, and industrial effluents contain phosphorus and
nitrogen, which can lead to eutrophication in surface waters, significantly
reducing their quality. The excessive use of fertilizers causes nitrate con-
tamination of groundwater, which can spread to drinking water sources
and cause oxygen deficiency in organ tissues, followed by a dangerous con-
dition called methemoglobinemia [9]. Many of the synthetic compounds
in use today are found in the aquatic environment and accumulate in the
food chain. POPs are extremely harmful for ecosystems and for human
health: they can easily accumulate in animals, plants, and especially in
aquatic organisms and thus enter the human food chain. Overexposure to
most POPs can lead to severe acute effects, while at lower exposure levels
long-term effects, such as endocrine disruption, reproductive and immune
dysfunction, neurobehavioral and developmental disorders, and cancer can
occur [10]. Oil spills can cause skin irritations and rashes. Lead and other
heavy metals have been shown to induce neurological problems, while
chemical and radioactive substances in water can cause cancer and birth
defects.
A substantial portion of the global pollution, responsible for the health
effects, listed above is generated as a result of industrial production pro-
cesses. Although it is largely recognized that the current production para-
digm is environmentally unsustainable, following an increasing linear trend
of resource consumption and overcontamination, society has always been
reluctant to face this issue and find a long-term solution. To preserve the
environment, keeping it clean for future generations, radical changes are
necessary in both the way society consumes and the way industry produces,
as the right balance has to be found. It was recognized that the majority of
people are not willing to change their consumer patterns and since in the
context of the free market economy it is the consumer behavior that shapes
the industrial policies, it becomes evident that if society stays passive, then it
is the industry that should find a way to produce sustainably. Today, indus-
try creates goods mostly by shaping matter in a top-down approach, relying
on energy-intensive production processes, generating substantial amounts
of waste. The total opposite of this would be a bottom-up approach, based
on product design using molecular building blocks, precisely positioned
through well-controlled, low-energy processes, barely creating any waste. It
is exactly what manufacturing on the nanoscale has promised: an alternative
