Rejection of endocrine disrupting compounds (bisphenol A, bisphenol F and triethyleneglycol dimethacrylate) by membrane:: technologies

Application of membrane technologies as treatment for wastewater has grown in recent years. Accordingly, this study aimed to determine the retention capacity of these technologies for high concentrations of non-charged organic molecules such as endocrine disrupters (bisphenol A, bisphenol F and triethyleneglycol dimethacrylate or TEGDMA), which are frequents in industrial wastewater and landfill leachate. Two modes of treatment were tested, the first consisting of a microfiltration module and an ultrafiltration module working in parallel, and the second consisting of a reverse osmosis module. The system was fed with treated and macrofiltered wastewater containing high concentration of each one of the assayed endocrine disrupters. Performance of the modules was variable and in each case dependent on the type of substance to be treated. Micro- and ultrafiltration membranes demonstrated certain effectiveness at retaining the three compounds owing to association with particulate material, which is retained efficiently by these systems. The reverse osmosis membranes achieved better results for bisphenol A than for TEGDMA, which is more insoluble and of larger molecular size, indicating that mechanisms other than size-based exclusion intervene in the process. Concentration of the compound in the influent also affected retention capacity. In the trials, bisphenol F was applied in higher concentrations than the other compounds and this led to higher concentrations of bisphenol F in the effluent. In all cases high concentrations of the assayed endocrine disrupters were still found in the treated effluents, casting doubt on the suitability of membrane technologies for removing these kinds of substances when high concentrations are presented in the influent to be treated.