Biology Reference
In-Depth Information
CHAPTER ONE
Introduction
Helen Bridle
Heriot-Watt University, Institute of Biological Chemistry, Biophysics and Bioengineering, Riccarton,
Edinburgh, Scotland
Access to potable water is essential to life. It is a right enshrined in the
Universal Declaration of Human Rights and it is critical to meeting all of
the Millennium Development Goals.
1
This is also recognized by the United
Nations (UN) General Assembly, which recently stated that safe and clean
drinking water and sanitation are a human right that is essential to the full
enjoyment of life. They designated the period from 2005 to 2015 as the
International Decade for Action, “Water for Life”.
Due to population growth, increased industrialization and climate
change, the scarcity of safe, pollutant-free drinking water sources is a
major problem. Numerous countries around the world already face
severe water shortages, and many more are considered water-stressed (see
Fig. 1.1
). It is estimated that 60% of the population of the world will suf-
fer water scarcity by 2025. In terms of waterborne contaminants, which
include inorganic and organic chemicals as well as pathogens/microbes,
the World Health Organisation (WHO) considers that microbial hazards
remain the primary concern in both developing and developed coun-
tries.
2
Safe drinking water poses no significant risk during a lifetime of con-
sumption. Globally, in 2012, nearly a billion people still lacked access
to safe drinking water. This is despite the announcement on March 6,
2012 that the Millenium Development Goal of halving the proportion
of people without access to an improved water source had been achieved.
In addition to acknowledging that numerous people are still without
access to safe drinking water, the WHO press release recognized that an
improved source of drinking water was not necessarily an assurance of
water quality and that work is still needed to ensure that these sources are,
and remain, safe.
Contaminated drinking water is one of the most significant environ-
mental contributors to the human disease burden. It is responsible for an
estimated 1.9 million deaths each year, predominantly in children under
