One aim of this study is to determine the impact of water velocity on the uptake of indicator polychlorinated
biphenyls (iPCBs) by silicone rubber (SR) and low-density polyethylene (LDPE) passive samplers. A second
aim is to assess the efficiency of performance reference compounds (PRCs) to correct for the impact of water
velocity. SR and LDPE samplers were spiked with 11 or 12 PRCs and exposed for 6 weeks to four different velocities
(in the range of 1.6 to 37.7 cm s−1) in river-like flow conditions using a channel system supplied with river
water. A relationship between velocity and the uptakewas found for each iPCB and enables to determine expected
changes in the uptake due to velocity variations. For both samplers, velocity increases from 2 to 10 cm s−1,
30 cm s−1 (interpolated data) and 100 cm s−1 (extrapolated data) lead to increases of the uptake which do
not exceed a factor of 2, 3 and 4.5, respectively. Results also showed that the influence of velocity decreased
with increasing the octanol-water coefficient partition (log Kow) of iPCBs when SR is used whereas the opposite
effect was observed for LDPE. Time-weighted average (TWA) concentrations of iPCBs in water were calculated
from iPCB uptake and PRC release. These calculations were performed using either a single PRC or all the PRCs.
The efficiency of PRCs to correct the impact of velocity was assessed by comparing the TWA concentrations
obtained at the four tested velocities. For SR, a good agreement was found among the four TWA concentrations
with both methods (average RSD b 10%). Also for LDPE, PRCs offered a good correction of the impact of water
velocity (average RSD of about 10 to 20%). These results contribute to the process of acceptance of passive
sampling in routine regulatory monitoring programs.