فهرست مطالب maria teresa saurini

Tributyltin is well recognized as an environmental endocrine disruptor and is listed as a priority substance that requires extended monitoring by the European Water Framework Directive (2000/60/EC). At the same time, due to their high pathogenicity, producing hormonal, immune, metabolic and reproductive dysfunctions, other butyltin species (e.g. monobutyltin, dibutyltin and tetrabutyltin) are consistently monitored in marine and freshwater aquatic ecosystems; the European Chemicals Agency classified these butyltin species as potential carcinogens and toxic substances for the human reproduction. Several analytical techniques, including gas chromatography and high-performance liquid chromatography, have been used to determine organotin species in aquatic ecosystems. Because of their chemical properties, organotin compounds result poorly stable upon temperature and are thus unsuited for direct analysis through capillary gas chromatography, which is usually performed after a derivatization step. The procedure described in this paper allowed the detection of underivatized chlorinated organotin compounds through gas chromatography-triple quadrupole mass spectrometry. Importantly, the obtained spectra of chlorinated monobutyltin and dibutyltin are herein presented and the fragmentation patterns are identified for the first time. The method was successfully applied to evaluate organotin compounds in sediments, providing the speciation of organotin species. Taking advantage of a simplified procedure of sample treatment, this study provided an innovative protocol for the gas chromatography/mass spectrometry of phenyl and butyl-substituted organotin compounds in contaminated sediments, capable of improving the efficiency of the conventional analysis of organotin compounds.

The 2013/39/EU Directive of the European Parliament provided a list of substances (organic and inorganic compounds); these so-called priority and dangerous priority substances affect the quality status of surface waters. Due to their high level of toxicity, these contaminants have legal limits in the order of µg/L and even some in the order of ng/L and pg/L. To this aim, an effective and sensitive analytical method for monitoring these contaminants was deemed necessary. In this experimental process, a highly effective workflow represented by a pre-analytical and an analytical phase was developed and validated. The pre-analytical phase comprises a liquid-liquid microextraction and a quick, easy, cheap, effective, rugged, and safe purification. The analytical part was performed by a very sensitive and robust multi-residual GC-MS/MS method without the need for derivatization. This method simultaneously identified and quantified most of these substances (represented by pesticides, chloroalkane hydrocarbons, and polycyclic aromatic hydrocarbons) at very low concentration levels while respecting the analytical concentration limits required by the European directive.