PASSIVE SAMPLING OF POLYCHLORINATED BIPHENYLS (PCB) IN POLLUTED KARST GROUNDWATER; Study case: Krupa, Slovenia

Polychlorinated biphenyls (PCBs) are synthetic organic compounds (209 possible isomers) of high physical, chemical and biological stability, and persist for long periods in a contaminated environment: they are undegradable (Hutzinger et al., 1974). They are biotoxically active compounds, and in animals and people cause acute and chronic damage to the skin, liver and lungs. In addition they cause metabolic disorders and disturbances to the action of the endocrine system, and are associated with loss of bodyweight and immuno-sensitivity. They are mutagenic and teratogenic, and are suspected to be carcinogenic (Safe, 1984). In Slovenia was an increase in use of PCBs after 1960. Between 1962 and 1983, a capacitor manufacturer disposed of PCB contaminated oil in the karstic region of Bela Krajina where it contaminated the spring of the Krupa River. The PCB pollution problems in karstic area of Krupa River are related to sinking surficial streams that mix with the regional groundwater supply, thus endangering the quality of the groundwater reservoirs.

 

The PCB pollution of the Krupa River drew the public’s attention to the chemical burden of Slovenians, and the demand for studies has been rising since. This study presents the application of the passive sampling technique for monitoring PCBs within the Krupa spring. Monitoring programmes for groundwater are largely based on the collection of grab (spot) samples. One of the methods used for such studies can also be passive sampling. Contrary to grab sampling, passive sampling is less sensitive to accidental extreme variations of the organic pollutant concentration in natural waters and it also allows for a large range of contaminants to be detected at once. A passive sampler can cover a long sampling period, integrating the pollutant concentration over time. Passive samples were analyzed by gas chromatography mass spectrometry (GC-MS). For the interpretation of chromatograms, the AMDIS deconvolution was used. The deconvolution was covered by the GC-MS library with retention times for 921 organic contaminants from Agilent USA, as well as by the NIST 2008 library of mass spectra.

The legacy of the PCB pollution of the Krupa River in Bela krajina is still measurable and passive sampling with active carbon fibres was proved to be an appropriate method for monitoring PCB pollutants in groundwater.