Benzo(a)pyrene in the lakes of the Southern Urals

The study investigated pollution of the Southern Ural lakes by benzopyrene. The sampling covered seventeen morphometrically different lakes of Chelyabinsk region and two water-storage reservoirs. In order to monitor the benzopyrene content in lake water, the determination technique of mass concentration of this highly toxic carcinogen in the samples has been suggested, based on high performance liquid chromatography with a "Fluorate-02" liquid analyzer as a detector and a detachable device HPLC-3. The technique in use was BP-M 01-21-2001 that included sample pretreatment, calibration of a liquid chromatograph and determination of benzopyrene based on its extraction from the water samples by n-hexane (methylene chloride). Identification of the benzopyrene peak on a chromatogram was carried out with the use of software package "MultiChrome". The quantitative determination of benzopyrene in water samples required the chromatographic analysis of a calibration solution and a pretreated sample. The study results were integrated into a summary table of benzopyrene content in the Southern Ural lakes which testified that benzo(a)pyrene was detected in all the investigated lakes and water-storage reservoirs in various concentrations, from the minimal of 0.2 TLV to 1-4 TLV. The scatter chart with confidence intervals showed that maximal hydrocarbon concentrations were in the 20-25 km zone of anthropogenic influence.