Search

This paper details the analytical strategy that was used to understand the origin of an acute taste and odour episode that induced the temporary shutdown of a plant serving several million customers in South America. The odour of the drinking water was described by local people as "olive odour". The odour of a first sample was described as green apple, fruity and olive oil by CIRSEE panellists. LLE and CLSAGC/ MS showed that the sample contained high levels of 2,4-ditertbutylphenol. When submitted to olfactory- GC/MS, the LLE extract revealed the presence of an intense sweet-fruity odour that did not match any of the MS peaks. Investigation of a second, more concentrated sample collected during the peak of the episode finally revealed that this main odour was due to 2-ethyl-5,5-dimethyl-1,3-dioxane (2EDD). The cis and trans isomers of 2-ethyl-4-methyl-1,3-dioxolane (2EMD) were also identified, together with a variety of plastic additives or oligomers. These compounds had been spilled by a polyester resin manufacturing plant. The characteristics of these episodes are compared with the rare similar episodes previously reported in the literature. [ABSTRACT FROM AUTHOR]

This paper illustrates the challenge faced by analytical chemists when trying to measure selected compounds representative of various classes of prescription and hospital drugs. Because hundreds of drugs belonging to a wide variety of chemical groups are allowed for use, an array of analytical methods has to be implemented. As an example, as part of the European Poseidon Project, five different methods were required to measure eight drugs and personal care products. These methods are discussed in detail. Examples of application to surface and ground waters from the Paris area are also reported. The antibiotics roxithromycin and sulfamethoxazole were detected for the first time in the Seine River downstream of Paris. The behaviour of the eight target compounds during aquifer recharge and drinking water treatment is described. An incident involving the detection of micrograms per litre levels of the personal care product Galaxolide in a drinking water distribution system is reported. The value of the pharmaceuticals and personal care products selected as potential indicators is also discussed. [ABSTRACT FROM AUTHOR]

This paper describes the implementation of a GC-Sniff/MS system that allows the simultaneous determination of the odorous properties of compounds eluting from a GC column and their identification by MS. The technique was first tested with standard compounds then applied to real cases of taste and odour episodes. This approach allowed the identification of geosmin at low levels and suggested the possible implication of methylnaphthalene in the development of chemical odours. It provided the first clue of the presence of a halophenol with a very low odour threshold involved in a chlorophenolic odour episode. The chemical was finally identified as 2,6-dibromophenol. The method was also applied to the characterization of a complex mixture of additives leaching from a flexible rubber pipe. In the latter case, Time-of-Flight MS was also used to confirm the identity of the additives. [ABSTRACT FROM AUTHOR]