C. de la Colina, F. Sánchez-Rasero, G. Dios, E. Romero and A. Peña
Recoveries of different pesticide groups after storage either on C18 cartridges or as dried residues from organic solutions, and their analysis by gas chromatography with electron capture and flame photometric detection, were studied. Two storage temperatures, 4 and -18 °C, and three storage periods, 3, 7 and 30 d, were considered. The effect of storage temperature and storage time on the recovery of 27 pesticides in water was investigated. In general, the pesticide recoveries were ≥70% after 30 d of storage at -18 °C on C18 cartridges. Exceptions included captan and folpet. The storage of the dried residues generally did not affect the pesticide recovery when kept at -18 °C for up to 30 d.