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POP model intercomparison study. Stage II. Comparison of mass balance estimates and sensitivity studies. DRAFT. EMEP/MSC-E Technical Report, 4/2005
2005
POP model intercomparison study. Stage II. Comparison of mass balance estimates and sensitivity studies. EMEP/MSC-E Technical Report, 5/2006
2006
POP model intercomparison study. Stage 1. Comparison of descriptions of main processes determining POP behaviour in various environmental compartments. EMEP MSC-E Technical Report, 1/2004
2004
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2006
2008
Polycyclic Aromatic Hydrocarbons Not Declining in Arctic Air Despite Global Emission Reduction
Two decades of atmospheric measurements of polycyclic aromatic hydrocarbons (PAHs) were conducted at three Arctic sites, i.e., Alert, Canada; Zeppelin, Svalbard; and Pallas, Finland. PAH concentrations decrease with increasing latitude in the order of Pallas > Zeppelin > Alert. Forest fire was identified as an important contributing source. Three representative PAHs, phenanthrene (PHE), pyrene (PYR), and benzo[a]pyrene (BaP) were selected for the assessment of their long-term trends. Significant decline of these PAHs was not observed contradicting the expected decline due to PAH emission reductions. A global 3-D transport model was employed to simulate the concentrations of these three PAHs at the three sites. The model predicted that warming in the Arctic would cause the air concentrations of PHE and PYR to increase in the Arctic atmosphere, while that of BaP, which tends to be particle-bound, is less affected by temperature. The expected decline due to the reduction of global PAH emissions is offset by the increment of volatilization caused by warming. This work shows that this phenomenon may affect the environmental occurrence of other anthropogenic substances, such as more volatile flame retardants and pesticides.
2019
Polycyclic aromatic hydrocarbons (PAHs) are not
declining in Arctic air despite reductions in their global emissions.
In Svalbard, the Longyearbyen coal-fired power plant
is considered to be one of the major local sources of PAHs.
Power plant stack emissions and ambient air samples, collected
simultaneously at 1 km (UNIS) and 6 km (Adventdalen)
transect distance, were analysed (gaseous and particulate
phases separately) for 22 nitro-PAHs, 8 oxy-PAHs,
and 16 parent PAHs by gas chromatography in combination
with single quadrupole electron capture negative ionization
mass spectrometry (GC-ECNI-MS) and gas chromatography
in combination with triple quadrupole electron ionization
mass spectrometry (GC-EI-MS/MS). Results confirm low
levels of PAH emissions (Sum 16 PAHs D 1:5 μg/kg coal)
from the power plant. Phenanthrene, 9,10-anthraquinone, 9-
fluorenone, fluorene, fluoranthene, and pyrene accounted for
85% of the plant emission (not including naphthalene). A dilution
effect was observed for the transect ambient air samples:
1.26+/- 0.16 and 0.63+/- 0.14 ng/m3 were the sum of all
47 PAH derivatives for UNIS and Adventdalen, respectively.
The PAH profile was homogeneous for these recipient stations
with phenanthrene and 9-fluorenone being most abundant.
Multivariate statistical analysis confirmed coal combustion
and vehicle and marine traffic as the predominant
sources of PAHs. Secondary atmospheric formation of 9-
nitroanthracene and 2C3-nitrofluoranthene was evaluated
and concluded. PAHs partitioning between gaseous and particulate
phases showed a strong dependence on ambient temperatures
and humidity. The present study contributes important
data which can be utilized to eliminate uncertainties in
model predictions that aim to assess the extent and impacts
of Arctic atmospheric contaminants.
2020
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2014
Polychlorinated biphenyls (PCBs) can be used as chemical sentinels for the assessment of anthropogenic influences on Arctic environmental change. We present an overview of studies on PCBs in the Arctic and combine these with the findings from ArcRisk—a major European Union-funded project aimed at examining the effects of climate change on the transport of contaminants to and their behaviour of in the Arctic—to provide a case study on the behaviour and impact of PCBs over time in the Arctic. PCBs in the Arctic have shown declining trends in the environment over the last few decades. Atmospheric long-range transport from secondary and primary sources is the major input of PCBs to the Arctic region. Modelling of the atmospheric PCB composition and behaviour showed some increases in environmental concentrations in a warmerArctic, but the general decline in
PCB levels is still the most prominent feature. ‘Within-Arctic’ processing of PCBs will be affected by climate change-related processes such as changing wet deposition. These in turn will influence biological exposure and uptake of PCBs. The pan-Arctic rivers draining large Arctic/sub-Arctic catchments provide a significant source of PCBs to the Arctic Ocean, although changes in hydrology/sediment transport combined with a changing marine environment remain areas of uncertainty with regard to PCB fate. Indirect effects of climate change on human exposure, such as a changing diet will influence and possibly reduce PCB
exposure for indigenous peoples. Body burdens of PCBs have declined since the 1980s and are predicted to decline further.
2018
2002