Uptake and release kinetics of 22 polar organic chemicals in the Chemcatcher passive sampler

Abstract

The Chemcatcher passive sampler, which uses Empore™ disks as sampling phase, is frequently used to monitor polar organic chemicals in river water and effluents. Uptake kinetics need to be quantified to calculate timeweighted average concentrations from Chemcatcher field deployments. Information on release kinetics is needed if performance reference compounds (PRCs) are used to quantify the influence of environmental conditions on the uptake. In a series of uptake and elimination experiments, we used Empore™ SDB disks (poly(styrenedivinylbenzene) copolymer modified with sulfonic acid groups) as a sampling phase and 22 compounds with a logK ow (octanol-water partitioning coefficient) range from −2.6 to 3.8. Uptake experiments were conducted in river water or tap water and lasted up to 25 days. Only 1 of 22 compounds (sulfamethoxazole) approached equilibrium in the uptake trials. Other compounds showed continuing non-linear uptake, even after 25 days. All compounds could be released from SDB disks, and desorption was proportionally higher in disks loaded for shorter periods. Desorption showed two-phase characteristics, and desorption was proportionally higher for passively sorbed compounds compared to actively loaded compounds (active loading was performed by pulling spiked river water over SDB disks using vacuum). We hypothesise that the two-phase kinetics and better retention of actively loaded compounds-and compounds loaded for a longer period-may be caused by slow diffusion of chemicals within the polymer. As sorption and desorption did not show isotropic kinetics, it is not possible to develop robust PRCs for adsorbent material like SDB disks.

Overview of the Chemcatcher® for the passive sampling of various pollutants in aquatic environments Part A: Principles, calibration, preparation and analysis of the sampler

“…A similar R s value of 0.12470.021 L day À 1 was also determined by O'Brien et al [32] at 19.3°C and a 0.161 m s À 1 flow velocity. Only one study is, at present time, available for a direct comparison of R s values obtained by means of different exposure systems (carrousel tank and channel system) [27]. Sampling rates were almost systematically (20 compounds out of 22) higher in the tank laboratory study.…”

“…The sampler is operating in the kinetic regime of accumulation and, in that case, sampling rates (R s ) and exposure times during which accumulation remains in the linear phase are needed. To improve the understanding on uptake mechanisms, experiments can also be carried out to determine sampler-water partition coefficients and kinetic constants for analyte uptake and elimination (see for instance [16,27]). Chemcatcher s calibration was generally performed by exposing samplers to known analyte concentrations for fixed periods under controlled conditions.…”

“…In addition, spot water samples were generally collected at regular time intervals and analyzed to check for variations in exposure concentrations. Temperature and pH, should be kept constant [27] or at least monitored during exposure.…”

Pesticide Contamination Monitored by Passive Sampling in Environmental Water of Japanese Coral Island

“…Chemcatchers Ⓡ were purchased from 3M Japan Ltd. (Tokyo, Japan), and the samplers with more compact design (Fig.2), which were similar to those used by Vermeirssen et al [14] in the sense that they held the disk and membrane between the plates, were fabricated for the use in shallow rivers.…”

Determining the suitability of a polar organic chemical integrated sampler (POCIS) for the detection of pesticide residue in the Ishikawa River and its tributary in Osaka, Japan

“…Various types of samplers with different characteristics, such as polar organic chemical integrative samplers (POCISs), 12,13) semipermeable membrane devices (SPMDs), 14) and Chemcatcher, 15) have been developed for the sampling of aquatic pesticides. Due to its ability to detect polar organic compounds, the POCIS has been considered an appropriate sampler for monitoring aquatic pesticides.…”