Multiresidue method for the determination of 32 human and veterinary pharmaceuticals in soil and sediment by pressurized-liquid extraction and LC-MS/MS.

An analytical chemical method has been developed for the simultaneous determination of 32 different pharmaceuticals in soils and sediments. The pharmaceuticals cover a varity of different compound groups. Soil samples were extracted with different solvents with the help of pressurized-liquid extraction (PLE) followed by clean-up using a solid-phase extraction (SPE) procedure.

Influence of the hydrophilic moiety of anionic and nonionic surfactants on their aerobic biodegradation in seawater.

The extent and kinetics of the primary biodegradation have been characterized for the most commonly-used surfactants, employing four homologues with the same alkyl chain: dodecyl ethoxy sulfate (C(12)AES), sodium dodecyl sulfate (SDS), dodecyl alcohol ethoxylate (C(12)AEO) and dodecyl benzenesulfonate (C(12)LAS). A brief acclimatization period has been required to enable an effective degradation of C(12)LAS and C(12)AES to take place, but this lag phase has not been detected for SDS and C(12)AEO. Primary biodegradation percentages at the end of these experiments were higher than 99%, showing a fast degradation rate in all cases (average half-life lower than 2 days).

Simultaneous determination of pesticides, polycyclic aromatic hydrocarbons and polychlorinated biphenyls in seawater and interstitial marine water samples, using stir bar sorptive extraction-thermal desorption-gas chromatography-mass spectrometry.

A method for the simultaneous determination of semi-volatile organic contaminants (polycyclic aromatic hydrocarbons, polychlorinated biphenyls, organochlorine and organophosphorus pesticides) in marine samples has been developed, for the first time, using the stir bar sorptive extraction technique (SBSE) and thermal desorption coupled to capillary gas chromatography-mass spectrometry (SBSE-TD-GC-MS). Polydimethyl siloxane (PDMS) was used for the extraction of the selected analytes and two procedures have been optimised and validated, one for seawater samples (100 mL) and another for interstitial water samples (10 mL), using PDMS stir bars of 20 mm and 10 mm size, respectively. The extraction and analytical conditions, such as extraction time, matrix effects, sample volume and desorption time, were optimised.

Effects of 17beta-estradiol and 4-nonylphenol on osmoregulation and hepatic enzymes in gilthead sea bream (Sparus auratus).

Sexually immature Sparus auratus were injected intraperitoneally with coconut oil either alone (control) or containing 17beta-estradiol (E2, 10 microg/g body mass) or 4-nonyphenol (4-NP, 100 and 200 microg/g body mass) and sampled 10 days later. Gill and kidney Na(+),K(+)-ATPase activities, plasma levels of E2 and cortisol, plasma osmolites (osmolality, sodium and chloride) and metabolites (glucose, lactate, proteins and triglycerides) were examined. Livers were used for measuring hepatosomatic index (HSI) and determinations of the activities of antioxidant defences catalase (CAT) and total glutatione peroxidase (t-GPX), the CYP1A-dependent, 7-ethoxyresorufin O-deethylase (EROD) and glutathione S-transferase (GST).