摘要

A fast and sensitive LC-MS/MS method suitable to monitor a set of 24 pharmaceuticals belonging to 9 therapeutical families was developed using an analytical column of reduced dimensions and an appropriate SPE procedure for acidic, basic and neutral analytes. Furthermore, a preliminary assessment of the occurrence and levels of these substances in surface waters of the Leca and Douro rivers, located in the north of Portugal, was conducted. Among 17 different SPE adsorbents tested, some of them often neglected, the JTBaker H2Ophilic provided the best recoveries (average 86%). When compared to the amino and quaternary ammonium adsorbents, the 1 degrees, 2 degrees amino proved the most suitable clean-up media for surface water samples prior to enrichment by SPE. The overall method provided limits of detection generally below 5 ng L-1 and a precision below or around 10% RSD in three non-consecutive days at 500 ng L-1 and around 12% at 50 ng L-1 concentration levels. The confirmatory capabilities of the method developed are especially welcome either through the MS3 spectra or the isotopic pattern. The first known results regarding the occurrence of pharmaceuticals in Leca river confirmed its expected high contamination load and the successful selection of the target pharmaceuticals. Concentrations up to 770 ng L-1 of bezafibrate, 925 ng L-1 of paracetamol, 389 ng L-1 of hydrochlorothiazide and 283 ng L-1 of furosemide were measured. The most ubiquitous in both seasons, February and June 2009, were bisoprolol, furosemide, bezafibrate and gemfibrozil. In Douro river the abundance and contamination level of pharmaceuticals was much lower which gives a clear indication that the hydraulic features of the river provide enough attenuation of the several contamination sources whereas Leca is highly impacted by insufficiently treated anthropogenic effluents.

  • 出版日期2013-1-1