Validation and application of an LC-MS/MS method for the simultaneous quantification of 13 pharmaceuticals in seawater

Knowledge of the presence of micropollutants such as pharmaceuticals, in coastal areas, is very limited; therefore, the main objective of this study was to optimize and validate a new analytical method for the quantitative analysis of 13 multiclass pharmaceuticals in seawater. Target compounds included antibiotics, non-steroidal anti-inflammatory drugs, beta-blockers, lipid regulators and one psychiatric drug. A combination of solid-phase extraction and liquid chromatography coupled with multiple mass spectrometry enabled their detection at the low nanogram per litre level. The limits of quantification varied between 1 and 50 ng L-1, for most components the linearities were more than 0.99 and the recoveries obtained in seawater (95-108%) were satisfactory. This method was applied to seawater and estuarine water samples collected in the Belgian coastal zone, to assess the prevalence of common pharmaceuticals in this marine environment. Seven phar-maceuticals, including compounds of which the presence in marine environments had not been reported earlier, were detected, with salicylic acid and carbamazepine being the most abundant, in concentrations up to 855 ng L-1.