Passive sampling has recently emerged as a cost-effective alternative to active grab and automated sampling techniques for the determination of realistic estimates of the average concentrations of contaminants in surface waters. The technique produces time-weighted average (TWA) concentrations relative to sampler exposure period, but requires a prior calibration step that has to be performed under controlled lab conditions. This means the accumulation kinetics of pollutants of interest have to be studied in order to determine the corresponding sampling rates needed to calculate TWA concentrations. However, it is well known that laboratory-derived analyte sampling rates may differ from in situ sampling rates because of the difference in the exposition conditions (for instance, flow velocity and temperature). Additionally, dissolved organic matter (DOM) may interact with hydrophobic analytes resulting in a modification of the fraction of such compounds in water available for passive sampling. Therefore, the determination of TWA concentrations may be biased. Identifying one or several performance and reference compounds (PRC) could allow to determine more realistic sampling rates and to calculate unbiased TWA concentrations during field exposition campaigns. Passive samplers can monitor a broad range of micropollutants, with various physical chemical properties. Moderately hydrophobic to highly hydrophobic compounds such as polycyclic aromatic hydrocarbons (PAH) and polychlorinated biphenyl congeners (PCB) are sampled by the Semipermeable Membrane Device (SPMD), whereas the Polar Organic Chemical Integrative Sampler (POCIS) has shown good results for the passive sampling of moderately polar chemicals such as pharmaceuticals compounds and hydrophilic pesticides. However, the integrative sampling of hydrophobic pesticides has been poorly reported in the literature. Stir Bar Sorptive Extraction (SBSE) is a solvent free sample preparation technique dedicated to the analysis of moderately hydrophobic compounds in aqueous samples. The extraction is performed on a stir bar composed of a magnet enclosed in a glass tube coated with a thick film of polydimethylsiloxane (PDMS or silicone). We have recently used these PDMS-coated stir bars as a passive sampling technique (named Passive SBSE) in lab calibration and for the monitoring of moderately hydrophobic to hydrophobic pesticides in surface water. The aim of this work was to study the impact of exposition conditions on the accumulation of selected pesticides in two passive samplers. On one hand, the effect of flow velocity, temperature and DOM on the accumulation kinetics of 20 moderately hydrophobic to hydrophobic pesticides in PDMS-coated stir bars used was evaluated. And on the other hand, the effect of flow velocity and temperature on the accumulation kinetics of 22 polar to moderately hydrophobic pesticides in POCIS (including 11 pesticides in common with Passive SBSE) was studied. The effects of these parameters were evaluated with a design of experiments, and the accumulation kinetic experiments were realized under controlled flow velocity, temperature, and concentrations of target pesticides and DOM in flow-through systems. The sampling rates were determined for each experiment and each target pesticide, and defined as the responses of the design. The results allowed us to identify for each sampler which pesticide accumulations were influenced by the experimental conditions, and to assess the relative effect of flow velocity, temperature and DOM on such pesticides. Simultaneously, we investigated on the elimination of two deuterium-labeled pesticides spiked in the PDMS-coated stir bars as PRC candidates prior to the kinetic experiments. The elimination coefficients of both PRC candidates were determined for each experiment and the design was processed a second time with the elimination constants as responses. Finally, the effect of the experimental conditions on the elimination kinetics were compared to that on the accumulation kinetics in order to identify which target pesticide accumulations could be corrected by the PRC candidate elimination data.