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A simple, sensitive, and selective solid phase extraction – ultra-fast liquid chromatography – tandem mass spectrometry (SPE-UFLC-MS/MS) method was developed and applied for the analysis of selected important pharmaceutical compounds in source and finished drinking waters. The method detected the following six pharmaceuticals, cotinine, cephapirin, ciprofloxacin, enrofloxacein, azithromycin, and diphenhydramine, at sub-μg/L level in multiple water matrices after pre-concentration by SPE. Cotinine-d3and13C315 N-Ciprofloxacin were used as internal standards for accurate quantitation. This method was validated through spike recoveries (67–129%), reproducibility (RSD: 2.3–15.7%), and method detection limits (MDLs: 2–5 ng/L). The method was used to test for occurrence of these pharmaceuticals in source and drinking waters from 13 Missouri water treatment facilities in four different seasons. In general, higher detection frequency and concentrations of pharmaceuticals were observed in colder months due presumably to less dilution (at lower flows) and slower degradation. The PPCP removals by different activated carbons were also evaluated. The occurrence and removal results in this study provide valuable information to help water treatment facilities taking appropriate strategies for better control of trace pharmaceuticals in drinking water. [ABSTRACT FROM AUTHOR]

Explosives are now persistent environmental pollutants that are targets of remediation and monitoring in a wide array of environmental media. Nitroguanidine (NG) and 2,4-dinitroanisole (DNAN) are two insensitive energetic compounds recently used as munitions explosives. To protect our environment and human health, the levels of these compounds in soils and waters need to be monitored. However, no sensitive analytical methods, such as liquid chromatography-tandem mass specirometry (LC-MS/MS), have been developed for detecting these new compounds at trace levels and to be concurrently applied to monitor the common explosives. In general, the concentrations of explosives in either soil or water samples are very low and widely distributed. Therefore, a List and sensitive method is required to monitor those compounds and increase our ability to find and address the threats they pose to human health and ecological receptor~ In this study, a fast and sensitive analytical method has been developed to quantitatively determine NG and DNAN in soil, tap water, and river water by using ultrafast LC-MS/MS. To make this method a comprehensive analytical technique for other explosives as well, it has induded other commonly used explosives in the method development, such as octahydro-l,3,S,7-teixanitro-l,3,S,7-tetrazocine (HMX), 1,3,5-trinitroper-hydro1,3,5-triazine (RDX), 2,4,6-trinitrotoluene (TNT), 2-amino-4,6-dinitrotoluene (ADNT), and pentaerythritol tetranitrate (PETN). The method detection limits (MDLs) of these compounds in soil ranged from 02 to S ppb, and a good linearity was obtained over a concentration range of 0.5-200 ppb. The recoveries of some compounds are equal to or better than the current EPA methods but with much higher sensitivities. [ABSTRACT FROM AUTHOR]