CHEMCATCHER PASSIVE SAMPLING OF AQUEOUS PERSISTENT ORGANIC POLLUTANTS: ASSESSMENT OF DIFFERENT MATERIALS

Abstract

Demand for sensitive and precious monitoring tool to determine trace level of pollutants in the aquatic environment led to the development of sorbent phase for passive sampling. The receiving materials as Cl 8, Styrene-divinylbenzene Exchange (SDB-XC), Styrene-divinylbenzene Reverse phase sulfonated (SDB-RPS) and the chelating disk have been evaluated for Chemcatcher. However, the adsorbents used so far are unable to retain the full range of the polar organic pollutants (POPs). Therefore, Oasis HLB (Hydrophile-Lipophule Balance) and SiliaPrepX HLB along with SDB-XC, SDB-RPS have been assessed for the uptake rate of the wide range of the fifty-nine POPs that include pesticides, pharmaceutical, herbicides. The logKow of the selected POPs ranged from —3.4 to 5.2. Initial pilot tests were done for geometrical placement of chemcatcher for final setup. Elbe River water is also used in the initial pilot test to study the matrix effect. In a final experiment, the sample was prepared by dissolving fifty-nine target POPs in the ultrapure Milli-Q water. Four, 7-day sorption batch renewal experiments were conducted in under controlled conditions of temperature, flow velocity and conductivity. Finally, Chemcatcher passive sampling was also done in Elbe River on two sites for seven days and simultaneously grab sampling was also done on the first and last day. The aqueous POPs were concentrated through solid phase extraction and the measurement by the HPLC-DAD (High-Performance liquid Chromatography with Diode Array Detector) and LCMS/ MS (Liquid Chromatography Mass Spectrometry). Recovery of the compound depends on the type of receiving media, geometry and elution solvents. Chemcatcher with a lower level in beaker has more recovery. In river water, recovery is lower due to a matrix effect. p1-I of water also influences the recovery of compounds. Out of 59 compounds, some has better recovery on SDB-XC and some (more polar) on SDB-RPS. Microcystin has a good recovery with SDB-XC. There was no accumulation of these seven compounds Acesulfame, Amidotrizot, Cyclamate, Gabapentin, Metformin, N-N Dimethylsulfamid and Saccharin on any of the receiving phase material. Out of 59, only 32 are present in Elbe River (Germany).