AWWA ACE58288

Water utilities to date have begun to consider the topic of "xenobiotics" in water. To bereasonably concise about the subject let us consider that xenobiotics include the followingfour 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 beenexamined in some detail. These are reviewed in terms relevant to public water supply. Themajority of data presented are based on work conducted as a doctoral project at theUniversity of New South Wales in Sydney, Australia (Khan, S, 2002). A comprehensive lookat the 50 highest use pharmaceuticals by mass in Australia demonstrated their presence inraw sewage, their distribution between solid and liquid phases in typical secondary sewagetreatment, and concentrations either measured or predicted to occur in solid and liquideffluents.Prediction of occurrence, fate and distribution depends on largely published chemicalcharacteristics 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 ofthe world were used to demonstrate model characteristics. This work clearly established thegeneral concept that compounds will be present in the environment, including sources ofpublic water supply, in proportion to production and use and as modified by predictable fateand distribution processes.Whether or not an individual compound would be found by any program of sampling andanalysis becomes purely a question of the whims of analytical chemistry. This in turn begsthe question of ultimate significance, i.e., what factors control biological effects of low levelexposure? This issue is examined in terms of the regulatory process, research progress intoxicology, and public perception. Includes 6 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

06/15/2003

Number of Pages:

12

File Size:

1 file , 640 KB