Biological Aspects of River Pollution

BIOLOGICAL aspects of river pollution were discussed at a joint session of Section D (Zoology) and K (Botany) of the British Association on September 5. Dr. B. A. Southgate, in introducing the subject, described briefly the varied types of domestic and industrial wastes discharged to surface waters. In indusraial districts the sewage treated at municipal sewege disposal works often contains a high proportion of waste liquors from manufacturing processes. Some constituents of these are incompletely removed during treatment of the sewage. For example, effluent from a works treating sewage containing gas liquor usually contains small quantities of thiocyanate and polyhydric phenols.