Page 8 - Partition & Adsorption of Organic Contaminants in Environmental Systems

PREFACE

The concern for the presence of a wide variety of contaminants in the envi-
ronment calls for development and assemblage of information about their
behavioral characteristics so that appropriate strategies can be adopted to
either prevent or minimize their adverse impacts on human welfare and
natural resources. This information is especially warranted for toxic chemicals
that persist for extended periods of time in the environment. When chemicals
enter the environment, they are usually not confined to a specific location but
rather are in dynamic motion either within a medium or across the adjacent
media. The propensity for a contaminant to move into and distribute itself
between the media (or phases) is determined by its physical and chemical
properties and environmental factors and variables. The quantity of a con-
taminant in a given medium and the state of its existence affect its environ-
mental impact. It is therefore important to understand what drives a
contaminant from one medium to another and the manner and extent that a
contaminant associates with the different media or phases within a local envi-
ronmental system.
This book is essentially a monograph that depicts the processes by which
nonionic organic contaminants are sorbed to natural biotic and abiotic sub-
stances. The book focuses on physical principles and system parameters that
affect the contaminant uptake by soil from water, air, and other media, by fish
from water, and by plants from soil and water. Since contaminant uptake by
natural organic substances is often predominantly by a partition interaction,
the partition characteristics in several solvent–water model mixtures are
treated in some detail to elucidate the relevant physicochemical parameters.
When addressing these subjects, the author has relied heavily on the views
drawn from his published studies and on those derived from other supporting
literature sources. At the risk of appearing immodest, the author has made
no attempt to give equal weight to all views on the subject, preferring instead
to present a coherent point of view that accounts for many observed
contaminant-uptake phenomena. This book is intended to be a good starting
point for beginning researchers in the field who might otherwise have diffi-
culties in making sense of the often conflicting and confusing literature.
The book is written primarily for graduate students and beginning profes-
sionals in environmental science and engineering in the hope that it will facil-
itate their research on contaminant sorption to soils and biotic species. Senior
scientists may also find the discussion on certain aspects of the sorption
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