Monitoring of hazardous substances at Alcantarilha's water treatment plant, Portugal

A monitoring programme of hazardous substances was implemented in Alcantarilha's water treatment plant (Algarve, Portugal) since 2002, in addition to the legally established monitoring of standard physical, chemical and microbiological parameters. The objective of this programme was to ensure the drinking water quality regarding the waterborne disease organisms Cryptosporidium, Giardia, Salmonella, Pseudomonas aeruginosa, enterovirus and cyanobacteria, and the potentially harmful chemicals aluminium, cyanotoxins, and disinfection by-products (THM) and their precursors (TOC, DOC, UV_{254 nm}, SUVA). Most of these parameters are new and still not regulated by the Portuguese and the European legislation. Data presented in this study refer to the period of August 2002 to October 2003. Results show that, despite the seasonal variations of the raw water quality, concentrations of the hazardous substances in the supplied drinking water were far below the legal standards and the WHO's and EPA guideline values, demonstrating the high removal efficiencies of this treatment plant.