Can we predict the removal of MIB and geosmin with PAC by using water quality parameters?

Cyanobacterial blooms in source waters are of concern as they can produce some compounds that are aesthetically unpleasant in potable water. Musty-earthy taste and odour compounds 2-methylisoborneol (MIB) and geosmin are produced by some species of cyanobacteria and actinomycetes. These compounds are low molecular weight volatile tertiary alcohols whose presence in treated water even at low ng L-1 levels can result in consumer complaints. Adsorption onto powdered activated carbon (PAC) is often used to remove these compounds during the treatment process. PAC is very efficient at removing these compounds but the presence of natural organic matter (NOM) reduces the efficiency of the PAC. For effective application of PAC the impact of NOM must be taken into account when determining the required dose. In this study the adsorption of MIB and geosmin from several waters was related to water quality parameters of dissolved organic carbon (DOC), UV absorbance at 254 nm and colour to determine if these could be used to predict adsorption. Results obtained showed that the water quality parameters of DOC and UV absorbance at 254 nm could be useful indicators for MIB and geosmin adsorption, although the relationship appears to be specific to the water source in question.