Landfills and waste water treatment plants as sources of ... - GKSS

STUDY 1: LANDFILLS AS SOURCES
concentrations may be explained by passing over highly populated and industrial areas west
from the sites. This is supported by Dreyer et al. (2009b) in air samples from the same region.
In contrast, the rapid decline in PFC concentrations in samples LB2 and RF17 can likely be
attributed to air masses that arrived with high velocities from coastal regions and thus shorter
residence time over those source regions (figure 16b).
a b
Figure 16 a, b: Selected seven days air mass back trajectories calculated for three hours
intervals (arrival height 2 m). Generated by Hysplit 4.8 using GDAS data for sample LB1 (a)
(�PFCs= 706 pg m -3 ) and sample LB2 (b) (�PFCs= 134 pg m -3 ). Triangles represent 12 h tags of
every trajectory. In addition, trajectory heights are plotted.
Taken the prevailing wind direction in account, it can be assumed that during the sampling
periods RFs were not contaminated by the landfills itsselves or by other potential sources that
are located between these sites. Thus, trajectory analysis supports the assumption that volatile
and semi-volatile PFCs originated from the landfills.
Ionic PFCs from particle phase determined in this study are in the same range as those
observed by Harada et al. (2005) for a rural region of Japan. However, PFOS and PFOA
concentrations were more than two orders of magnitude lower than those of Barber at al.
(2007) and Harada et al. (2005) in urban areas of UK and Japan, respectively. In contrast to
other studies of Dreyer et al. (2009b) and Barber et al. (2007), who observed PFOS and
PFOA in maximum proportions, PFBA was the most dominant compound in this study.
However, in samples LA3, LA4 and LB4 PFHxA was detected in highest proportions. For
ionic PFCs distinct differences between landfills and their corresponding RFs were not
observed. Moreover, samples are characterized with high variation in concentrations and
proportions indicating an enhanced uncertainty of these data, probably due to revolatilisation
of PFCAs from GFF (Arp and Goss 2008).
Musk fragrances were detected predominantly in the gas phase which confirms other studies
(Peck and Hornbuckle 2004; Peck and Hornbuckle 2006; Xie et al. 2007). In general, total
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