Investigation of caffeine, Gemfibrozil, Bezafibrate, Metformine, Prometazine, and Loratadine in waters of public supply systems

ABSTRACT

The present study aimed to investigate the occurrence of the drugs Caffeine, Gemfibrozil, Bezafibrate, Metformin, Promethazine, and Loratadine in water supply and water for human consumption. To determine the occurrence of drugs, six sampling campaigns were carried out during the rainy season and six during the dry season, at three collection points located in the Bolonha Complex, Belém city, Northern Brazil: Bolonha reservoir (catchment) and Bolonha filtered water chamber and treated water reservoir. To evaluate the removal of drugs in the filtration and disinfection stages, the efficiencies of each of these processes were calculated, in addition to the removal evaluation at the end of the treatment. The raw water was the one with the highest concentrations of drugs, while the treated water had lower concentrations. The concentrations of lipid regulators Bezafibrate and Gemfibrozil ranged from 11.4 to 1,364.9 ng·L^-1 in raw water and from 15.7 to 435.9 ng·L^-1 in treated water. The antiallergic Loratadine was the drug with the highest frequency of occurrence whose concentration ranged from 15.7 to 45.0 ng·L^-1 in raw water and from 15.2 to 24.3 ng·L^-1 in treated water. The results indicate the anthropic influence that the reservoir and the filtered water chamber and treated water reservoir have been suffering and show that the full cycle treatment used in Bolonha filtered water chamber and treated water reservoir was not efficient for the complete removal of the compounds of emerging concern investigated. The average annual removals were, respectively, 5% for Gemfibrozil, 26% for Loratadine, and 52% for Bezafibrate. The chlorination step seemed to be particularly important for the removal of Gemfibrozil and Caffeine.

Keywords:
drugs; microcontaminants; anthropic influence; drinking water