[Derivative spectroscopy and its use in sanitary hygiene control].

An analytical method is developed for defining the residual quantities of rodenticide "Brodifacoum" (talon) used in the control of harmful field rodents and especially for species Microtus. The method is based on extracting the pesticide with chloroform and making use of spectrophotometry in the ultraviolet field in intervals 340-240 nm. The second derivative of the absorption is utilized as well as the band with maximum 288 nm and minimum 228 nm. The peak height in this interval is in proportion to the concentration of the brodifacoum. When analysing residual waters, reservoirs, and soil the elimination of impeding substances is performed by thin-layer chromatography. The "cis" and "trans" form of brodifacoum is jointly determined by spectrophotometry. At thin-layer chromatography processing the two forms are separated. Sensitivity of the method 0.5 microgram/cm3 (in chloroform solution). Reproduction (as coefficient of variation) 5%. A thin-layer chromatographic method is recommended for semiquantitative determination of brodifacoum.