Water utilities to date have begun to consider the topic of "xenobiotics" in water. To be
reasonably concise about the subject let us consider that xenobiotics include the following
four categories of chemicals: endocrine disruptors; pharmaceutical residuals;
personal care products; and, other trace substances not falling in the other 3 categories.
The origins and behavior of pharmaceutical residuals in the environment have been
examined in some detail. These are reviewed in terms relevant to public water supply. The
majority of data presented are based on work conducted as a doctoral project at the
University of New South Wales in Sydney, Australia (Khan, S, 2002). A comprehensive look
at the 50 highest use pharmaceuticals by mass in Australia demonstrated their presence in
raw sewage, their distribution between solid and liquid phases in typical secondary sewage
treatment, and concentrations either measured or predicted to occur in solid and liquid
effluents.
Prediction of occurrence, fate and distribution depends on largely published chemical
characteristics and on degradative processes in sewage treatment and in the environment.
Actual data collected from raw and treated sewage samples at eight STP's in various parts of
the world were used to demonstrate model characteristics. This work clearly established the
general concept that compounds will be present in the environment, including sources of
public water supply, in proportion to production and use and as modified by predictable fate
and distribution processes.
Whether or not an individual compound would be found by any program of sampling and
analysis becomes purely a question of the whims of analytical chemistry. This in turn begs
the question of ultimate significance, i.e., what factors control biological effects of low level
exposure? This issue is examined in terms of the regulatory process, research progress in
toxicology, and public perception. Includes 6 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 640 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 12 |
| Published : | 06/15/2003 |
