1.1 Studies carried out in several countries have
shown that many species of bacteria, plants, and animals can survive
in a viable form in the ballast water and sediment carried in ships,
even after journeys of several months' duration. Subsequent discharge
of ballast water or sediment, into the waters of port States, may
result in the establishment of harmful aquatic organisms and pathogens
which may pose threats to indigenous human, animal and plant life,
and the marine environment. Although other media have been identified
as being responsible for transferring organisms between geographically
separated water bodies, ballast water discharge from ships appears
to have been among the most prominent.
1.2 The potential for ballast water discharge
to cause harm has been recognised not only by the International Maritime
Organization but also by the World Health Organization, which is concerned
about the role of ballast water as a medium for the spreading of epidemic
disease bacteria.
1.3 These guidelines are not to be regarded as
a certain solution to the problem. Rather, each part of these guidelines
should be viewed as a tool which, if correctly applied, will help
to minimize the risks associated with ballast water discharge. As
scientific and technological advances are made, the guidelines will
be refined to enable the risk to be more adequately addressed. In
the interim, port States, flag States and other parties that can assist
in mitigating this problem should exercise due care and diligence
in an effort to conform to the maximum extent possible with the guidelines.
1.4 The selection of appropriate methods of risk
minimization will depend upon several factors, including the type
or types of organisms being targeted, the level of risk involved,
its environmental acceptability, the economic and ecological costs
involved and the safety of ships.