Polycyclic aromatic hydrocarbons (PAHs) and synthetic musks reflect the existence of “classic” and “emerging” pollutants, respectively. Both families of chemicals have toxicological potential towards humans and ecosystems, which calls for a continuous monitoring. Active sampling stations are expensive to acquire and maintain, so there has been an increasing search for cheaper alternatives. Vegetation has consistently been one of the solutions employed, and pine needles are among the most used matrices due to their characteristics that favour the entrapment of this type of contaminants. This work intends to be a follow-up of a seasonal sampling strategy performed in Portugal in 2007, with some improvements. Thus, a biannual sampling scheme (autumn 2011 and spring 2012) was performed on 29 sites in mainland Portugal, covering urban, industrial, rural and remote areas. As was previously found by the work group, pine needles from the species Pinus pinaster showed the highest entrapment capacity among the most extended species in the country. Therefore, it was chosen to collect needles from pines of that species. In places where these were not found (Évora and Lisboa), P. pinea was used instead. In some places, where trees of the two species were in close proximity, samples of the two were taken for further comparison. Regarding the results, urban and industrial sites show similar pollution behaviour, followed by rural places, while remote areas reflect very low levels. The north-western regions of Portugal is more related to high levels of PAHs than the south-eastern ones. This is due to the inherent distribution of urban pressure and heavy industry as well important maritime ports. It was also revealed that urban sites show more disperse individual PAHs patterns, which is most likely due to the more numerous sources. A temporal trend was also visible, showing a decrease in the incidence of heavier PAHs in the warmer sampling campaign, which is explained by a reduction of industrial activity combined with an exodus of population for the summer holidays. On contrary, sample sites located in exclusively industrial areas, this trend is not visible, which may enforce the former mentioned conclusions. In the eastern part of the country an increase in the colder months in heavier PAHs was also verified, which may be mainly due to increased domestic heating needs. The trends for synthetic musks are more difficult to establish, but in this case the warmer period tends to reflect the enhanced use of personal care and cosmetic products.

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