M. Zanette et al., REVISION OF THE REGULATORY SEMISPECIFIC METHODS FOR THE DETERMINATIONOF SURFACTANTS IN AQUEOUS SAMPLES .2. ANIONIC SURFACTANTS, Annali di chimica, 85(5-6), 1995, pp. 221-233
Two analytical protocols for the determination of MBAS (Methylene Blue
Active Substances) in environmental aqueous samples, respectively pro
posed by the Italian CNR Water Research Institute (IRSA) and by the In
ternational Organisation for Standardisation (ISO), were compared to d
isclose the most remarkable differences. A revision of the present reg
ulatory method (IRSA E-017) for the determination of anionic surfactan
ts in waters was undertaken. Improvements of the current procedure wer
e proposed regarding the choice of reference material and the employme
nt of a specific calibration curve for quantitation of MBAS in surface
waters. Laboratory experiments were carried out on both synthetic and
real water samples in order to evaluate precision and accuracy of the
method. The experimental results showed that the MBAS method overesti
mates the anionic surfactant content in waste water samples from a mec
hanical-biological sewage treatment plant, especially in the final eff
luent.