Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous and semivolatile pollutants associated with emissions from both natural and anthropogenic sources. For decades, the atmosphere has been considered an efficient vehicle for pollutants transport around the world. In order to assess the atmospheric occurrence of PAHs across a transect in the Southwest Atlantic Ocean, air samples were collected aboard the oceanographic vessel ARA Puerto Deseado (CONICET), during two consecutive research campaigns in October–November 2014. Total PAHs were dominated by gas phase levels of Phenantrene, Dibenzothiophene, Fluorene, Fluoranthene and Pyrene in a concentration range of 57–5778 pg m⁻³. Characteristic diagnostic ratios of some PAHs were estimated in order to assess their possible emission sources showing important contribution from petrogenic and pyrogenic origin. Additionally, air mass back trajectory calculation revealed a marked influence of air with oceanic origin, being the contribution from the South American continent scarce. PAHs levels showed a decreasing trend from the coast towards open ocean, with exception of those sites that showed continental air masses influence.

多环芳烃（PAHs）是普遍存在的半挥发性污染物，与自然和人为来源的排放相关。数十年来，大气一直被认为是在世界范围内进行污染物传输的有效工具。为了评估西南大西洋横断面上大气中PAHs的发生，在2014年10月至11月的两次连续研究活动中，在海洋航行船ARA Puerto Deseado（CONICET）上收集了空气样本。总的PAHs以气体为主导菲，二苯并噻吩，芴，荧蒽和P的相态浓度范围为57-5778 pg m ^-3。估算了某些多环芳烃的特征诊断率，以评估其可能的排放源，这些源显示出了成因和热源作用。此外，气团返回轨迹的计算还揭示了来自海洋的空气的显着影响，这是南美大陆稀缺的原因。从沿海到公海，PAHs含量呈下降趋势，但那些受到大陆气团影响的位点除外。