<p>The sixteen US-EPA priority PAHs in 32 surface soils were investigated to elucidate their contamination levels, sources and migration between the coast and highlands in Tanzania. The ∑₁₆PAHs ranged from 0.23 to 159.95&#xa0;ng/g, with predominance of low molecular weight PAHs (LPAHs). PAHs sources are primarily pyrogenic, as evidenced by five Positive Matrix Factorization (PMF) factors: mixed natural and agricultural sources (63.26%), combustion of wood and biomass (18.61%), industrial energy (8.19%), vehicular emissions (2.1%), and uncombusted fuel (7.84%). Spatially, PAH distribution revealed clear patterns from the coast to the highlands, with hotspots in the eastern and south-eastern lowlands. The PAHs were negatively correlated with altitude, and there was a significant positive correlation between 3- and 4-rings with 2-rings PAHs, and between 5- and 6-rings PAHs. The upper surface soil sorbed HPAHs, while LPAHs lost primarily through preferential leaching in highly wet soils. PAH transport is mainly inter-regional with a predominance of localized deposition of high molecular weight PAHs (HPAHs), although coastal soils are susceptible to PAH deposition from transboundary sources. Moreover, coastal condition enhanced volatilisation, with this effect decreasing farther inland. Unexpectedly, a similar trend was mirrored in the central-western highlands. Therefore, this study provides baseline data for PAHs in the country’s environment and uncover the underexplored potential of global distillation of PAH along high to low pressure zones in tropical countries like Tanzania. It also highlights the need to integrate PAH into public health and environmental management related policies to reduce risks of exposure.</p>