Numerous species of vegetation have been used consistently as matrices for the biomonitoring of environmental contaminants, with particular emphasis given to forests, due to their omnipresence associated with relatively long and stable life cycles. In particular, references to several pine species are common (especially their needles). It is however unlikely that two samples exposed to the same environmental contamination but collected from dissimilar species present the same results. The differences may determine a disparity in the retentive capacities towards a given pollutant. As such, the trustworthy comparison of data from past or future biomonitoring studies relating to different species (in this case pine) is challenging. This work aims to be a starting point to reduce this important gap. That is, to obtain valid relationships between the uptakes of different pine species towards given pollutants while strengthening the knowledge of the levels and cycles of pollution. To do so, samples of pine needles from several species were collected in different countries (Portugal, Spain, UK and Romania) in sites where at least two species coexist side by side, to ensure a similar environmental exposure. In total, needles from the species Pinus (P.) pinea, P. pinaster, P. halepensis, P. radiata, P. sylvestris, P. nigra, P. canariensis and P. strobus were collected from 12 sites, according to the availability of adjacent trees in each one of them. Profiting from a multi-residue analytical protocol that is able to quantify several families of semi-volatile organic contaminants (SVOCs), the relationships of some representative chemicals of 4 classes of SVOCs - polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs) – were established. Since pine needles mainly retain the atmospheric chemicals that predominantly appear in the gas phase, those were chosen preferably. In general, the levels of the target compounds found in the samples reflected the urban pressures, regardless of the species. Being the most sampled species, it was possible to establish statistically significant relationships for some chemicals between P. pinea and P. pinaster and P. sylvestris and P. pinaster. For the other species, some indications were given as to their uptake ability. To establish other correlations, more sampling is needed, but the difficulty in finding the required sites can be a hindering factor.

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