Using biomonitoring tool to assess the performance of a lab-scale water reclamation process

Abstract

The mutagenicity assessment for samples collected from a lab-scale water reclamation system, which included the influent, samples after microfiltration (MF) and reverse osmosis (RO) were carried out. Influent water was found to be mutagenic to TA98 (±S9) and non-mutagenic to TA100 (±S9). Samples after MF and RO were mutagenic to both the bacteria strains (±S9), with much higher mutagenic ratio (MR) values observed got MF filtrates. Comparing the specific mutagenic activities of the samples, it was found that there was an overall reduction, approximately 10-fold in mutagenicity from the influent to the treated water. Reduction in mutagenicity was also seen after the RO process but increase after the MF process. This was attributed mainly to the chlorination process before and after MF process, which could have contributed to DBPs' formation. However, due to the dissolved organics removal by RO process, the specific mutagenicity was largely reduced. RO was found to be very efficient at reducing mutagenicity of treated water. © 2005 American Water Works Association WQTC Conference All Rights Reserved.