ESCHERICHIA-COLI - A POTENTIAL SOURCE OF NATIVE FECAL-COLIFORMS IN PULP AND PAPER-MILL EFFLUENTS - IT DOES NOT NECESSARILY POSE A HEALTH-HAZARD

Enterotoxin-negative Escherichia coli (E. Coli) were identified in the effluent of an integrated paper mill. An inplant examination showed t hat the bacteria were entering the process water via the chip screw pr essates prior to the pulp digester. The source of bacteria was fresh w hole log or saw mill chips having no known history of contact with sew age. The results of this study and others would suggest that some E. c oli species may represent environmental rather than fecal strains. The validity of using E. coli as indicators of sewage contamination in pu lp and paper mill effluents is therefore questioned.