a b s t r a c tBoth polyurethane foam (PUF) and sorbent-impregnated PUF (SIP) passive air sampling (PAS) methods were deployed and compared separately for the analysis of organophosphate esters (OPEs) in outdoor atmospheric environment. During an continuous period of 84 days, parallel samples were also collected by a high-volume active air sampler (HV-AAS) to assess the contamination levels and to calibrate uptake parameters of PAS. The total concentration of OPEs in both particulate and gaseous phases ranged from 1.50 to 5.64 ng m Ă 3 in ambient air. Tris(2-chloroisopropyl) phosphate (TCPP) was the dominating analog, representing 78 79% of total OPE concentration. SIP-PAS showed longer linear-phase sampling period for TCPP, and accumulated more amount of the most volatile triethyl phosphate (TEP) and tributyl phosphate (TBP) homologues, while similar sorption performances of both PAS methods were found for most of the semi-volatile OPEs. Linear sampling rates in PUF-PAS and SIP-PAS disks were calculated for individual OPEs except for TEP and TBP, and the average uptake rates (3.37 1.1 and 3.57 1.7 m 3 d Ă 1 , respectively) were close to the acknowledged value (4 m Ă 3 d Ă 1) for persistent organic pollutants. Besides, isotopic labeled D 15 -Triphenyl phosphate (TPhP) could be used as a viable depuration compound to calculate site-specific sampling rates of OPEs, with a linear loss of up to âŒ60% at the end of deployment time.