N against poxviruses. The use of pharmaceuticals in Candesartan Atacand livestock production is a potential source of environmental contamination. Antibiotics and antifungal compounds are used for therapeutic treatment, among others as medicated feed. Veterinary pharmaceuticals are excreted unchanged or as metabolites and may enter the environment via agricultural run off, causing surface, groundwater and soil contamination. Possible impacts of antibiotics on the environment include toxicity and the emergence of antibiotic resistance. Development of resistance to antifungals is an increasing problem in veterinary and human medicine. Multi drug resistance is frequently observed. Also, through exposure to azole residues, fungi become cross resistant to the medical triazoles. Incidences of antifungal resistance have been reported, both in the veterinary and medical field. Jadhav reported fluconazole, nystatin and clotrimazole resistance exhibited by Candida albicans isolated from man, animals and birds. Similarly, Thomas reported antifungal drug resistancefrom Cryptococcus neoformans isolated from human, animals, birds and the environment. Among the fungal isolates from canine cystitis, Candida albicans and Candida tropicalis were resistant to fluconazole and amphotericin B. The hypothesis that azole resistance appeared in the environment was demonstrated in previous studies. Regarding the toxicity of these compounds, previous research has revealed the potentially adverse impact of some azole antifungals on endocrine systems of aquatic organisms. Today there is no systematic monitoring of surface and groundwater for residues of pharmaceuticals and fungicides in Europe. Water quality standards for pharmaceuticals should be determined by risk assessment studies, and a database collecting all results should be established. For a monitoring program to be implemented, it will require the availability of screening and confirmatory methods. In analytical chemistry there is a clear tendency to expand existing methods into multi methods, enabling the determination of different classes of compounds in one analysis. Currently, multi methods are typically carried out using LC systems coupled to triple quadrupole mass spectrometers.
Although these methods are highly selective, sensitive and precise, this approach has limitation because it is intended for targeted acquisitions. This explains the new tendency to use time of flight or Orbitrap mass spectrometers, appropriate for untargeted or post target analyses, which allow increased Nilotinib numbers of compounds to be analysed and offer a retrospective view to investigate unknown compounds present in the samples. Present TOF technologies do not meet the performances of quadrupole in respect of selectivity and linearity. The medium high resolution for TOF MS of 10,000 FWHM significantly affects the sensitivity and selectivity of the measurements. Hernando et al. described a TOF MS method for multi residue scanning in edible portions of salmon. The reported CC values for non authorised compounds ranged from 13 to 65 g kg1. The successful use of a tandem quadrupole TOF instrument for screening of 13 pharmaceutical contaminants in water at low concentrations was described by Stolker et al. in 2004. The Orbitrap mass analyser typically.
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