On-line solid phase extraction and liquid chromatography/tandem mass spectrometry to quantify pharmaceuticals, pesticides and some metabolites in wastewaters, drinking, and surface waters

A simple on-line method was developed for the analysis of pharmaceuticals, pesticides and some metabolites in drinking, surface and wastewater samples. The technique is based on the use of on-line solid-phase extraction combined with liquid chromatography electrospray tandem mass spectrometry with positive electrospray ionization (LC-ESI(PI)-MS/MS). The injection of only 1 mL of filtered water sample is used with a total analysis time of 20 min, including the period required to flush the SPE cartridge with organic solvent and reconditioning the LC column. Method detection limits were in the range of 2 to 24 ng L(-1) for the compounds of interest, with recoveries from 87 to 110% in surface as well as wastewater samples. Matrix effects were observed for some compounds without exceeding more than 25%. All results displayed a good degree of reproducibility, with relative standard deviations (RSD) of less than 12% for all compounds. Moreover, at least 200 samples were analyzed without altering the performance of the pre-concentration column. This method was preferred over traditional off-line procedures because it minimizes tedious sample preparation, increases productivity and sample throughput. The analysis of various water and wastewater samples showed that caffeine, carbamazepine and atrazine could be detected in all the samples analysed and the selected compounds are always present in at least one of the sample types.     

PLATE JUNCTIONS AND HYDROCARBON ACCUMULATIONS IN THE INDIAN REGION

This article relates the productive and potential oil fields in India to plate junctions and other major tectonic features. High geothermal gradients are known to accelerate the expulsion of petroleum from the source bed, as well as its migration and accumulation in favourable reservoir rocks, resulting in high yield. Some of the world's major petroleum deposits occur along ‘failed arms’ associated with the plume generated triple junctions. Seven triple junctions have been located in the Indian region, and two more are identified here. Interestingly, India's off-shore petroleum prospects coincide with some of these triple junctions. Cet article établit la relation entre les champs de pétrole en production et potentiels en Inde à la théorie des plaques et à d'autres traits tectoniques importants. L'on sait que des gradients géothermiques élevés accélèrent l'expulsion du pétrole à partir de la roche-mère et favorisent la migration et l'accumulation dans des réservoirs convenables. Quelques-uns des plus grands champs de pétrole du monde se rencontrent en liaison avec des ‘bras morts’ associés avec un système triple de fossés d'effondrement. Sept systèmes triples ont été repérés en Inde et deux autres sont reconnus ici. II est intéressant de remarquer que les possibilités pétrolières de l'offshore indien coïncide avec certains de ces systèmes triples. Este artículo establece la relación entre los campos petrolíferos en producción y potenciales de India a la teoría de placas y otros aspectos tectónicos. Es sabido que una gradiente térmica alta ascelera la expulsión del petróleo desde la roca madre y favorece su migración y acumulación en rocas reservorio favorables. Algunos de los mayores depósitos de petróleo se encuentran a lo largo de los “brazos muertos” asociados a un sistema triple de unión de placas. Siete uniones de este tipo habia sido localizadas en India y otros dos más son identificados aquí. Es interesante notar que las posibilidades petroleras en la zona marítima de India coinciden con alguna forma de sistemas triple de placas.