Permeation sampling of halogenated ether priority pollutants

Abstract

A method for the determination of five halogenated ether priority pollutants using time-weighted-average concentrations is described. These compounds permeate through a silicone polycarbonate membrane and are trapped onto a Tenax TA™ adsorbent. Compounds of interest are solvent desorbed by acetone, followed by separation and quantitation by gas chromatography-mass spectrometry (GC-MS). A linear relationship was found between the amount of halogenated ether trapped onto the Tenax adsorbent and the product of the concentration of ether in solution and the exposure time. Concentrations ranged from 0.04 to 7.2 mg/L for a twenty-four hour exposure. The temperature of solution was found to alter the pollutant permeation rate. This sampler offers the advantages of providing time-weighted-average concentrations with a relatively simple sampling method. 1275

Development of a novel passive sampling system for the time-averaged measurement of a range of organic pollutants in aquatic environments

“…This effect has been investigated for other types of passive sampling systems. 21,27,42 An Arrhenius relationship has been established over the temperature range of 18±24 ³C for the accumulation rate of phenanthrene by the semi-permeable membrane device (SPMD) in which the analyte diffuses through a polyethylene membrane into an arti®cial lipid receiving phase. 21 Sampling rates of PCBs by the PISCES sampling system comprising a polyethylene enclosed hexane receiving phase have been quoted to vary between 0.41 l day 21 at 10 ³C and 0.92 l day 21 at 20 ³C.…”

“…25 Arrhenius relationships have also been evaluated for halogenated ether compounds in a system with XAD resin as receiving phase and a polycarbonate membrane. 42 The effects of temperature on the passive sampler are not easy to model analytically because of the complexity of the system, which comprises an unstirred boundary layer of water, a polymeric membrane, and an organic receiving phase. Under stagnant conditions, such as those found at the sediment surface, the boundary layer is typically of the order of 1 mm thick but in faster ¯owing waters this would be much smaller, estimated to be in the range 0.1±0.001 mm.…”

Diffusional behaviour of metals in a passive sampling system for monitoring aquatic pollution

“…These have in common a receiving phase with a high affinity for the target species, which is separated from the aquatic environment by a diffusion limiting barrier. [1][2][3][4][5][6][7] These devices are based on the principles of Fickian diffusion, and a diffusion gradient is maintained across the diffusion limiting barrier by using a receiving phase with a high affinity for the analyte being monitored. A range of receiving phases have been employed in these devices, including l-hexane 2 and triolein lipids 4 and a bound C 18 chromatographic phase 7 for organic compounds, and chelating resins, 1 disks and ion-exchange gels 8,9 for inorganic species.…”

“…The measured value for a batch case is calculated from eqn. (6) and is also presented in Table 2. Both the calculated value in pure water from eqn.…”