The Global Monitoring Plan of the Stockholm Convention
on Persistent
Organic Pollutants (POPs) was established to generate long-term data
necessary for evaluating the effectiveness of regulatory measures
at a global scale. After 15 years of passive air monitoring (2003–2019),
MONET is the first network to produce sufficient data for the analysis
of continuous long-term temporal trends of POPs in air across the
entire European continent. This study reports long-term concentrations
of 20 POPs monitored at 32 sites in 27 European countries. As of January
1, 2019, the concentration ranges (pg/m3) were 1.1–52.8
(∑6PCB), 0.3–8.5 (∑12dl-PCB),
0.007–0.175 (∑17PCDD/F), 0.02–2.2
(∑9PBDE), 0.4–24.7 (BDE 209), 0.5–247
(∑6DDT), 1.7–818 (∑4HCH),
15.8–74.7 (HCB), and 5.9–21.5 (PeCB). Temporal trends
indicate that concentrations of most POPs have declined significantly
over the past 15 years, with median annual decreases ranging from
−8.0 to −11.5% (halving times of 6–8 years) for
∑6PCB, ∑17PCDD/F, HCB, PeCB, and
∑9PBDE. Furthermore, no statistically significant
differences were observed in either the trends or the concentrations
of specific POPs at sites in Western Europe (WEOG) compared to sites
in Central and Eastern Europe (CEE), which suggests relatively uniform
compound-specific distribution and removal at the continental scale.