EPA-PAHs

In SPE, a small amount of organic solvent or surfactant is added to collected samples to prevent adsorption to sample containers. To increase recoveries of ng 1 levels of PAHs in SPE, ACN (40%) or surfactants above their CMC can be added to samples prior to preconcentration. Solid supports, chemically modified with copper phthalocyanine trisulfonic acid derivatives for selective sorption of PAHs, have been investigated. The selective interaction is thought to be with the tt electrons of the PAHs. Brij-35, a neutral polyoxyethylene lauryl ether surfactant was added above the CMC to water samples to prevent sorption on container walls. Before preconcentration by SPE, samples were diluted to reduce the surfactant concentration to just below the CMC. Recoveries of over 90% for SPE on solids containing copper phthalocyanine trisulfonic derivatives were obtained for spiked water samples at low ngl levels, except for NAP, ACE, and FLU. Experiments repeated using a C18 SPE preconcentration sorbent gave >90% recovery for all 16 EPA PAHs, except for ACY. Examples of the use of SDB as an SPE sorbent include the online analysis of seawater from the coast of Catalonia in Spain, where no PAHs above the low ng 1 level were detected, and the analysis of leachate from coal deposits. ... 

PHN, ACE, PYR, CHY, B[a]P, and benzo[e]pyrene were separated in a 50 mM borate buffer (pH 9) containing a mixture of 20 mM neutral methyl-(3-cyclodextrin (M(3CD) and 25 mM anionic sulfobutylether-(3-cyclodextrin (SB(3CD) at 30 kV and 30°C. " B[a]P and benzo[e]pyrene were successfully resolved with the other compounds in under 11 min in a 50-cm effective length of capillary without micelles in the mobile phase. The system was also less sensitive to temperature and separation potential. LIE detection with excitation at 325 nm at 2.5 mW from a He/Cd laser coupled to an optical fiber allowed for detection limits in the sub ppb range. The method described above was applied to the analysis of contaminated soil that had been extracted by supercritical CO2 for 20 min at 120°C and collected in methanol/DCM. ° Of the 16 EPA PAH mixtures, eleven compounds were detectable in the low ppb range. Ten of the eleven detectable compounds were measured in the soil extract. When compared to RP-HPLC, CE values were slightly lower but only six compounds were detected by HPLC-FLD. No direct relationship between PAH molecular size, polarity, or volatility with migration order was observed and B[b]F/B[k]F isomers were readily separated. 

Reversed-phase EC on chemically bonded Cig (octadecylsilane) stationary phases is by far the most popular liquid chromatographic mode for separation of PAH compounds. Resolution is greatly influenced by the type of synthesis used to prepare the bonded phase. Good resolution can be achieved for the 16 US EPA PAHs on polymeric Cig phases. However, some isomers are unresolved (chrysene and benzo[a] anthracene) or only partially resolved [htmo ght perylene and indeno[l,2,3-cd]pyrene, benzo[ ]fluor-anthene, and benzo[ ]fluoranthene, or fluoranthene and acenaphthene) when monomeric Cig phases are used. 

As internal quantitation standards C-labelled BDE 209 (SOng/mL), Relabelled PCB 101 (40 ng/mL) and a 16 EPA-PAHs mix as RC-labelled compounds (2 ng/mL) is spiked to the final extract. 

Groundwater 16 EPA PAHs 3 X 60 mL CH2CI2 (sep. funnel 2 L) Comparison with SPMDs [191]... 

Foods are quite complex matrixes for any kind of monitoring. Due to the multiplicity of food matrices, it is not possible to use one sample preparation technique, so many methods have been proposed for meeting all the requirements. There are few national or international standard methods related to B(a)Py in food samples, but also little information about collaborative trials has been published so far [335,336]. Furthermore, the majority of the reports of analytical methods to monitor hydrocarbons in foods have been focused on the determination of B(a)Py exclusively or on the 16 EPA PAHs. Several works are starting to show up which includes the determination of the 15 PAHs recommended by the EU in food samples [336-338]. 

Figure 2 Elevated PAH concentrations (sum of EPA-PAHs, 1 - and 2- methylated naphthalenes and perylene) in Saar and Mosel River floodplain soils, Germany [16]. The flow direction is from SW to NE and the Saar coal rnining area is near Saarburg. Coal transportation by ships occurred from the mining area via the Saar River, towards NE into the Mosel River and further into the Rhine River.

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