Current Analytical Chemistry - Volume 12, Issue 3, 2016

It is well known that there is a widespread use of veterinary pharmaceuticals and consequent release into different ecosystems such as freshwater bodies and groundwater systems. Furthermore, the use of organic fertilizers produced from animal waste manure has been also responsible for the occurrence of veterinary pharmaceuticals in agricultural soils. This article is a review of different studies focused on the detection and quantification of such compounds in environmental compartments using different analytical techniques. Furthermore, this paper reports the main challenges regarding veterinary pharmaceuticals in terms of analytical methods, detection/quantification of parent compounds and metabolites, and risks/toxicity to human health and aquatic ecosystems. Based on the existing literature, it is clear that only limited data is available regarding veterinary compounds and there are still considerable gaps to be bridged in order to remediate existing problems and prevent future ones. In terms of analytical methods, there are still considerable challenges to overcome considering the large number of existing compounds and respective metabolites. A number of studies highlight the lack of attention given to the detection and quantification of transformation products and metabolites. Furthermore more attention needs to be given in relation to the toxic effects and potential risks that veterinary compounds pose to environmental and human health. To conclude, the more research investigations focused on these subjects take place in the near future, more rapidly we will get a better understanding about the behavior of these compounds and the real risks they pose to aquatic and terrestrial environments and how to properly tackle them.

This paper describes the optimization and validation of an analytical method for the determination of 83 pharmaceutically active compounds (PhACs) in aqueous samples using solid-phase extraction (SPE) followed by ultra performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-QqQ-MS/MS). First, several experiments were conducted to optimize different SPE extraction parameters such as pH, elution solvents, and Na2EDTA addition. Extraction recovery percentages were between 17 and 146%, being higher than 70% for 47 target analytes. The effect of salinity in the extraction efficiency proved to be negligible (< 20% within a range from 0 to 38 g L-1). The method limits of detection (LOD) and quantification (LOQ) were below 1 ng L-1 for most compounds (> 90%), and the precision of the method, calculated as the relative standard deviation (RSD) of replicate extractions and analyses, was less than 20%. The optimized method was successfully applied to the analysis of real water samples in estuarine and coastal systems from SW Spain (Cadiz Bay and Huelva Estuary). 49 out of 83 target compounds were found in 75% of samples. Ibuprofen, atenolol, gemfibrozil and caffeine were the most commonly detected substances, reaching concentrations up to 195 ng L-1.

During the last years there has been a growing interest in the research focused on the pharmaceutical residues in the environment. Those compounds have been recognized as a threat to environmental stability, due to their inherent biological activity and their pseudo-persistency. Nevertheless, the analysis of pharmaceuticals in environmental samples is still a very difficult and demanding task, due to the fact that environmental concentrations of these compounds are mostly in the ng L-1 to μg L-1 ranges and due to the complexity of the analyzed samples. Therefore, there has been increasing interest in the development of new, more selective and sensitive methods for their monitoring in environmental samples. Hence, the aim of our study is to present the overview of the analytical challenges, of the development of analytical methods used in exposure assessment, and of the priorities for future research. Moreover, as many studies published to date concentrate mainly on freshwater ecosystem, in our work we want to focus on the analysis of different marine ecosystem compartments (water, sediment, biota), as this is a critical knowledge gap in environmental studies.

Anthelmintics are intensively used for veterinary treatment and after being released into the environment can ultimately pose environmental and health hazards. However, to date, there has been very limited information on the concentrations of anthelmintics in the aquatic environment. The monitoring of these compounds in different compartments (water, sediment and fish tissue samples) is crucial if a thorough risk assessment is to be made. In this study, such an analytical approach is presented for the first time. As model compounds, two benzimidazoles: flubendazole (FLU) and fenbendazole (FEN), and doramectin (DOR) representing avermectins, were selected. As a model aquatic environment - the Reda river in northern Poland was chosen. The water, sediment and fish tissue samples were collected in 2014, the sediments were also collected in 2013. All of the compounds were detected at least once in the survey. All of the risk quotients, apart from DOR in waters, were lower than 1, thus no risk to the environment can be derived from these results. However, in the case of DOR, such a risk was observed. The results were compared with those published for Poland and other countries. In summary, the simultaneous determination proposed here of anthelmintics in different compartments, significantly improves the environmental risk assessment of this class of drug.

In recent years, there has been a growing concern in the scientific community regarding the presence of pharmaceuticals in drinking water samples and the potential risks to humans from exposure to traces of pharmaceuticals via drinking water. These have been present in these matrices for a long time, but the importance of this fact has only been elucidated in the past few years. The increased interest in this field arises from the fact that they are not considered under the legislation which regulates water quality. However, they may be introduced in future legislation, because many organizations, e.g. the World Health Organization, have elaborated the need for more systematic studies on the transport, occurrence and fate of pharmaceuticals in drinking water sources. One important limitation of such studies is the availability of sufficiently sensitive and reliable analytical methods for these investigations. Moreover, standardization of the protocols for the sampling and the analysis of pharmaceuticals is required, in order to better facilitate the comparison of data. This review summarizes the analytical methods for the determination of pharmaceutical residues in drinking water samples. The current methodology and future prospects, as well the capabilities, the potential and the limitations of the analytical protocols that are used for determining pharmaceuticals in drinking water are described and discussed in detail. These methods have been used to monitor not only the native compounds and some of their metabolites, but also the formation of degradation products during water treatment.

The presence of pharmaceuticals in drinking water has been a subject of concern for the last ten years because many of these pollutants are persistent in such aquatic matrices. Latest studies have shown that they can pose a ecotoxicological risk due to their potential long-term negative effects on living organism, even though the relatively low concentrations of these compounds in drinking water (ng/L). For this reason, several researchers have been investigating the roles of various drinking water treatment (DWT) processes in the efficiency of these polar pollutants elimination to decrease their release into the drinking water system. What more, from several years the monitoring programs and advance risk assessment are being carried out in order to gives important information for indicators finding (for future monitoring) and consequential regulations. This study critically reviews available literature on pharmaceutical residues in drinking water, starting from their occurrence, fate and finally toxicology significance. Presented review is also presenting the issue of pharmaceuticals detection and products occurred after drinking water treatment. Moreover, it is also intended to provide an proposition into what future directions might be taken by drinking-water regulators, governments, and water suppliers in their challenging task of enhancing the availability of data on the fate, behavior, and ecotoxicity of pharmaceutical residues in drinking water, in order to be fully aware of the potential risks to humans from exposure to traces of pharmaceuticals via drinking water.