Occurrence and fate of 7 APIs in two sewage treatment plants - and their reactions to tertiary treatment

Abstract: In recent years concerns have been raised about micropollutants, such as pharmaceutical ingredients, being released into the aquatic environment. As a consequence, signs of adverse effects on biota have been identified. Also, potable drinking water is a precious and potentially finite resource that need be taken care of. Sewage treatment plants have been identified as point sources for emissions of micropollutants originating from modern way of life. The problem is that the sewage treatment plants of today are not built to handle these kinds of pollutants. One possibility is however to supplement existing processing equipment with new technology to overcome that deficiency. In this thesis, the ability, of two sewage treatment plants, to remove seven active pharmaceutical ingredients of different structure and class have been investigated. All seven were found in at least one of the influent samples and only one was removed to any significant level in one of the treatment plants. Effluent samples were then subjected to tertiary treatment by ozonation, activated carbon or biochar to investigate the possibility of further reducing the concentrations in the effluent. Activated carbon proved to be very efficient and to some extent ozone. However, ozonation trials were inconclusive due to contamination of samples.