Bacterial biofilms formed in arsenic-containing water: Biodeterioration of water network materials

S.E. RASTELLI; B. M. ROSALES; M.R.VIERA; C.I. ELSNER

Journal of Water Supply: Research and Technology - AQUA

IWA Publising

Año: 2015 vol. 64 p. 738 - 748

Theimmersion of any material in a water system triggers a surface microbialcolonization which simultaneously influences the corrosion behavior of thesubstratum. The present study was focused on the As(V) influence on the biofilmformation and their consequences on the corrosion behavior of differentsubstrata. Commercial materials used in water distribution networks: alloysbased on Fe, Zn and Cu and polypropylene (as blank) were tested in laboratorywater closed circuits either in the absence or presence of 5 mg L_1 As(V).Microbial sessile counting, microscopic techniques (SEM, ESEM, CSLM), andanodic polarization curves were performed. All the materials revealed very differentbehaviors. Except for copper, bacterial counts were higher for those couponsexposed to the water with As(V). The morphology of the corrosion products aswell as the development of the corrosion process were highly influenced by thecharacteristics of the microbial biofilm, the nature of the substrata, and thepresence or not of As(V).