McKay, Donald. "Front matter" Multimedia Environmental Models ...

available from the University of Toronto. A link is maintained from the Trent website,
at which other models are available.
As better models of global fate become available, they will provide an invaluable
tool with which humanity can design, select, and use chemicals on our planet with
no fear of adverse consequences. Whether we will be sufficiently enlightened to
achieve this is a question only time will answer.
©2001 CRC Press LLC
8.17 CLOSURE
Perhaps the task addressed by this book is best summarized by Figure 8.14,
which depicts many of the environmental processes to which chemical contaminants
are subject. The aim has been to develop methods of calculating partitioning, transport,
and transformation in the wide range of media that constitute our environment.
Ultimately of primary concern to the public, and thus to regulators, is the effect that
these chemicals may have on human well-being. But there are sound practical and
ethical reasons for protecting wildlife, and indeed all fellow organisms in our ecosystem.
It is not yet clear how severe the effects of chemical contaminants are, nor is it
likely that the full picture will become clear for some decades. Undoubtedly, there
are chemical surprises or “time bombs” in store as analytical methods and toxicology
improve and new chemicals of concern are identified.
Regardless of the incentive nurtured by public fear of “toxics,” environmental
science has a quite independent and noble objective of seeking, for its own sake, a
fuller quantitative understanding of how the biotic and abiotic components of our
multimedia ecosystem operate; how chemicals that enter this system are transported,
transformed, and accumulate; and how they eventually reach organisms and affect
their well-being.
Modern society now depends on a wide variety of chemicals for producing
materials, as components of fuels, for maintaining food production, for ensuring
sanitary conditions and reducing the incidence of disease, for use in domestic and
personal care products, and for use in medical and veterinary therapeutic drugs. We
enjoy enormous benefits from these chemicals. Our industrial, municipal, and
domestic activities also generate chemicals inadvertently by processes such as incineration
and waste treatment. The challenge is to use chemicals wisely and prudently
by reducing emissions or discharges to a level at which there is assurance that there
are no adverse effects on the quality of life from chemicals, singly or in combination.
It is hoped that the tools developed in these chapters can contribute to this process.