Monitoring pharmaceuticals and personal care products in reservoir water used for drinking water supply

Abstract

In this work, the presence of selected emerging contaminants has been investigated in two reservoirs, La Fe (LF) and Riogrande (RG), which supply water to two drinking water treatment plants (DWTPs) of Medellin, one of the most populated cities of Colombia. An analytical method based on solid phase extraction (SPE) of the sample followed by measurement by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was developed and validated for this purpose. Five monitoring campaigns were performed in each reservoir, collecting samples from 7 sites (LF) and 10 sites (RG) at three different depths of the water column. In addition, water samples entering in the DWTPs and treated water samples from these plans were also analyzed for the selected compounds. Data from this work showed that parabens, UV filters and the pharmaceutical ibuprofen were commonly present in most of the reservoir samples. Thus, methyl paraben was detected in around 90% of the samples collected, while ibuprofen was found in around 60% of the samples. Water samples feeding the DWTPs also contained these two compounds, as well as benzophenone at low concentrations, which was in general agreement with the results from the reservoir samples. After treatment in the DWTPs these three compounds were still present in the samples although at low concentrations (<40ng/L), which evidenced that they were not completely removed after the conventional treatment applied. The potential effects of the presence of these compounds at the ppt levels in drinking water are still unknown. Further research is needed to evaluate the effect of chronic exposure to these compounds via consumption of drinking water.

Emerging Contaminants in Trans-American Waters

“…14 n. 6, e2436 -Taubaté 2019 found; the most-concentrated were atrazine (Mean: 12.1, maximum value: 19 ngL -1 , 100%), and caffeine (Mean: 3.54 μgL -1 , Maximum: 18.83 μgL -1 , 100%) (Machado et al, 2016). In a study conducted in Colombia, in the Río Grande and La Fe de Medellín reservoirs, 6 of the 9 ECs studied were found, among them ibuprofen (max 62 ngL -1 ) (Aristizabal-Ciro et al, 2017). Eleven of eighteen ECs studied were found in the Esmeraldas River, source of drinking water for the population of Esmeraldas in Ecuador; benzoylecgonine, a coca metabolite, was found with the highest concentration (Mean: 37.5 μgL -1 ) (Voloshenko-Rossin et al, 2014).…”

Use of Ultrasound as an Advanced Oxidation Process for the Degradation of Emerging Pollutants in Water

“…Equations (1)- (4) show the decomposition of water and other molecules commonly dissolved in water by sonochemical waves [9,39], being the HO•, as well as the hydroperoxyl radicals (HO 2 •), the main species that oxidizes the organic compounds present in the aqueous medium.…”

“…These authors investigated the presence of different inorganic anions to determine their influence on the process. The anions evaluated were Cl − , SO 4 2− and NO 3 − , and it was found that Cl − slightly restricted the degradation of the investigated drug, while the others did not have a significant impact on the degradation of the compound of interest. This slight inhibition in CBZ degradation due to the presence of Cl − can be attributed to the reaction of this ion with the HO• dispersed in the solution, resulting in the formation of ClOH• − .…”

“…In the research conducted by Villaroel et al [54], the influence of ionic constituents of water on the degradation of ACP (82.69 µmol L −1 and 1.65 µmol L −1 ), at a power of 60 W and ultrasonic frequency of 600 kHz, was evaluated. The results obtained in distilled water and in synthetic water containing calcium ions (Ca 2+ ), magnesium ions (Mg 2+ ), sulphates ions (SO 4 2− ), bicarbonates ions (HCO 3 − ), Cl − , potassium ions (K + ) and fluorides ions (F − ) were compared. The results indicated that, for the lowest concentration of ACP, a more pronounced acceleration of degradation was observed when this occurred in water with similar ion content than in distilled water.…”

“…The presence of ECs in the environment was not measured or controlled in the past because they did not cause concern and, in general terms, there were no studies demonstrating a health risk to humankind and living beings. Additionally, the use of ECs was not as high as it is currently; and they were not detected in water, since advances in instrumental analytical chemistry have only recently permitted their quantification at ultra-trace and trace concentrations [4,5], i.e., at concentrations from ng L −1 to µg L −1 [3,6]. Indeed, in the last years, ECs have been identified and quantified in effluents from wastewater treatment plant effluents, surface water, groundwater and even drinking water [3,5,7,8].…”