The distribution, seasonal variation and sources of 16 polycyclic aromatic hydrocarbons (PAH) from suspended particulate matter (SPM) of the Aurá River, a small amazon typical river located in Northern Brazil, were determined. Gas chromatography–mass spectrometry analysis of SPM revealed a mixture of PAH from different origins and a seasonal variation of PAH primary source for the studied area. Pyrene was the dominant PAH in both studied periods. Total PAH content (ΣPAH) ranged from lower than quantification limit (< LOQ) to 2498.2 ng g⁻¹ dw during the dry season and < LOQ to 2865.8 ng g⁻¹ dw during the wet season. Low molecular weight PAH (LMW) represented 51% of ΣPAH during the dry season and 29% during the wet season. It was noted, by comparing previous data, that the main source of these compounds was altered after the deactivation of an irregular landfill next to the river.

中文翻译：

---

来自巴西亚马逊河内城市化河流中悬浮颗粒物的PAH剖面图。

确定了位于巴西北部的亚马逊小河Aurá河中的悬浮颗粒物（SPM）中的16种多环芳烃（PAH）的分布，季节变化和来源。SPM的气相色谱-质谱分析表明，不同来源的多环芳烃混合在一起，并且该地区的多环芳烃主要来源存在季节性变化。在两个研究时期中，was都是主要的PAH。PAH的总含量（ΣPAH）在干燥季节从低于定量限（<LOQ）到2498.2 ng g ^-1 dw，从<LOQ到2865.8 ng g ^-1在雨季的dw。在干旱季节，低分子量PAH（LMW）占ΣPAH的51％，在潮湿季节占29％。通过比较以前的数据，注意到这些化合物的主要来源在河边不规则的垃圾填埋场停用后发生了变化。