Environ Sci Pollut Res (2015) 22:19887-19895 
19889 
Ô Springer 
Surrogated and deuterated compounds (Table 1) were used 
as performance reference compounds (PRC), compounds that 
are spiked into the passive sampler prior to deployment and 
whose dissipation rates can be used to estimate sampling rates. 
Internal standards (IS) were added prior to extraction of sam 
plers to compensate for variations during sample preparation. 
Silica gel (Chromabond, Macherey&Nagel, Germany) was 
used as solid-phase material in the SPE clean-up step. 
Instrumentation 
Pressurized liquid extraction was performed with an acceler 
ated solvent extraction system (ASE 350, Dionex, CA, USA). 
Ultrapure water was obtained from a Milli-Q water purifica 
tion system (Integral 5 Millipore, MA, USA). Gravimetric 
analysis were performed on a scale with ¿/=0.001 g (Sartorius, 
Germany). 
F1PLC-SEC was performed on a system consisting of a 
F1PLC pump (L-6200, Merck-Hitachi, Germany), an injection 
valve (Rheodyne), a column oven (Techlab, Germany) with a 
Phenogel column (5 pm. 50 A, Phenomenex, USA), a fluo 
rescence detector (JASCO, Japan) and a fraction collector 
(Foxy 200 ISCO, USA). 
Concentration was performed either with a parallel solvent 
concentrator with two backflush cooling zones (Syncore 
Q101, BUCHI, Switzerland) or with nitrogen. 
The silicone oligomer content was determined using a total 
reflection X-ray fluorescence analyzer (TXRF 3 Picotax, 
Rontec, Germany). 
Analysis of PAFls was performed with a GC-MS system 
(GC CP-3800 coupled to Varian 1200, both Varian, CA, USA) 
using a Varian Factor Four Capillary Column VF-5 ms sepa 
ration column (30-m length, 0.25-mm ID, 0.25-pm film thick 
ness) (Varian Associates, CA, USA) in selected ion monitor 
ing mode (SIM). Flelium 5.0 (Linde, Germany) with a flow 
rate of 1 mL/min was used as carrier gas. The injection was 
performed split/splitless (split opens after 3 min), with an in 
jection volume of 2 )iL. The temperature gradient for chro 
matographic separation was as follows: start 60 °C for 
0.2 min, temperature increase to 100 °C in 5 °C/min steps, 
temperature increase to 320 °C in 3.5 °C/min steps and a final 
constant temperature for 4 min. The injection was carried out 
with a cold injection system with a starting temperature of 
60 °C, following an increase of 10 °C/s to a final temperature 
of 280 °C, The temperatures of transfer line, ion source and 
quadrupole were 275, 250, and 40 °C, respectively. The quan 
tification of target analytes was performed with internal 
standards. 
Determination of chlorinated hydrocarbons (CFICs) was 
performed with a GC-MS ion-trap system (GC CP3800 
coupled to a Saturn 2200, both Varian, CA, USA) in the 
multi-reaction monitoring mode (MRM). As separation col 
umn, a FIT 8 (0.22 mm ID, 25 m length, 0.22 pm film 
thickness) (SGE Analytical Science, Milton Keynes, UK) 
was used, with a desactivated pre-column (2- to 5-m length, 
0.53-mm ID) (Agilent, Germany). 
Flelium 5.0 (Linde, Germany) with a flow rate of 1.3 mL/ 
min was used as carrier gas. The injection was performed split/ 
splitless (split opens after 3 min), with an injection volume of 
2 pL. The temperature gradient for chromatographic separa 
tion was as follows: start 90 °C for 1 min, temperature increase 
to 170 °C in 10 0 C/min steps, temperature increase to 290 °C 
in 3 °C/min steps and a final constant temperature for 40 min. 
The injection was carried out with a cold injection system with 
a starting temperature of 90 °C, following an increase of 5 °C/ 
s to a final temperature of 250 °C, The temperatures of trap, 
manifold and transfer line were 200, 80, and 280 °C, respec 
tively. The axiale modulation of the ion-trap was 4.1 V. The 
quantification of target analytes was performed with internal 
standards. 
Optimizing ASE parameters for silicone rubber 
pre-cleaning 
ASE is used for the first time as a pre-cleaning tool for PDMS 
strips in this study. The release of small polymers from sili 
cone rubber (oligomers) by different solvents was tested for 
eight solvents and combinations, which are used typically for 
pre-cleaning (ethylacetate, acetone, и-hexane, mediano l/л - 
pentane (1:1), acetonitrile/methanol (2:1), dichloromethane/ 
acetone (1:1), n-hexane/acetone (1:1 v/v) and n-hexane/ace- 
tone (3:1 v/v)) (Rusina et al. 2007; Schafer et al. 2010; Ezzell 
and Richter 2012; Smedes and Booij 2012; Allan et al. 2013). 
Past studies investigated polymer swelling in organic solvents, 
which lead to an enhanced fragility of PDMS strips and block 
age of solvent flow through the ASE extraction cell (Rusina 
et al. 2007; Shahpoury and Flageman 2013). Thus, oligomer 
release and swelling was quantified by gravimetric analysis. 
Pre-weighted silicone strips (55x90x0.5 mm) were folded 
into extraction cells (22 mL) with glass fibre filters in the 
screw cap and extracted with each solvent (-mixture) at 
100 °C using the parameters given in Table 2. 
After extraction, strips were wiped with a paper tissue 
(Kimtech, Kimberly-Clark), quickly wrapped in pre 
weighted aluminium foil to prevent evaporation of absorbed 
Table 2 ASE instrumentation parameters for different experimental 
approaches 
Temperature (°C) 
Static time (min) 
Cycles 
Solvent tests 
100 
10 
2 
Time series 
100 
10-90 (Ю-min steps) 
1 
Temperature tests 
75; 100; 125 
10 
5 
All extractions were performed with 1500 psi pressure, 50 % flush and 
5 min oven heat