Polycyclic aromatic hydrocarbons (PAHs), mostly originate from human activities, are persistent organic pollutants (POPs). PAHs were found to be related to multiple diseases and threatened to human health seriously. 

With the recent rapid development of urbanization, PAHs have attracted wide attention, particularly in remote regions such as Tibetan Plateau (TP). Therefore, it is essential to investigate the spatio-temporal distribution and sources of PAHs on the TP. 

Recently, scientists from the Northwest Institute of Eco-Environment and Resources of Chinese Academy of Sciences, together with their colleagues from domestic and foreign research institutes and universities, investigated the sources and spatio-temporal distributions of PAHs on the TP by combining aerosol sample data from six sites in 2014 and 2016. 

The study showed that tricyclic PAHs can change from particulate to gaseous phase. It can be seen that the tricyclic PAHs were dominant PAHs on the TP (44%-58%) indicating long-range atmospheric transport as the major source of PAHs. 

Principal component analysis (PCA) and diagnostic ratio analysis showed that biomass and coal combustion were the major sources of PAHs in inland areas of the TP. However, marginal plateau areas were affected by fossil fuel emissions. 

This study is essential to systematically understand the characteristics of organic aerosol pollution and its distribution over broad areas of the TP and assess the impact of pollution on humans and ecosystems. 

This study has been published in the Environmental Pollution in an article entitled “Sources and spatio-temporal distribution of aerosol polycyclic aromatic hydrocarbons throughout the Tibetan Plateau”.