The author wishes to express his sincere gratitude to the
Chief chemist, Government chemist and the chief engineer,
engineer Maina, ministry of public works, and materials
branch for support during the entire research period when
there was inadequate funding. The good co-operation of
the deputy government chemist, Mrs. Okado and the Head
of Departments in both foods and water and the whole
government chemist staff is highly acknowledged. Special
thanks go to Professor Jane Murungi and Dr. Charles
Onindo of Kenyatta University for their supervision of the
thesis and helpful critical comments that resulted in the